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Question 1
Correct
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A new-born was found to have an undeveloped spiral septum in the heart. This is characteristic of which of the following?
Your Answer: Persistent truncus arteriosus
Explanation:Persistent truncus arteriosus is a congenital heart disease that occurs when the primitive truncus does not divide into the pulmonary artery and aorta, resulting in a single arterial trunk. The spiral septum is created by fusion of a truncal septum and the aorticopulmonary spiral septum. Incomplete development of these septa results in incomplete separation of the common tube of the truncus arteriosus and the aorticopulmonary trunk.
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This question is part of the following fields:
- Cardiovascular
- Pathology
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Question 2
Correct
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A 35 year old male patient sustained a traumatic head injury. The patient had loss of consciousness, woke up momentarily when he was in the emergency room but became drowsy and comatose a few hours after. CT scan of the brain showed accumulation of blood between the dura and the cranial bone on the left side of his head. What type of haemorrhage did the patient have?
Your Answer: Epidural
Explanation:Epidural hematoma, also known as epidural bleeding, is a type of traumatic brain injury (TBI) in which a build-up of blood occurs between the dura mater (the tough outer membrane of the central nervous system) and the skull. The spinal cord is also covered by a layer of dura mater, so epidural bleeds may also occur in the spinal column. Often due to trauma, the condition is potentially deadly because the build-up of blood may increase pressure in the intracranial space, compressing delicate brain tissue, and causing brain shift. The condition is present in one to three percent of head injuries. Around 15–20% of epidural hematomas are fatal.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 3
Incorrect
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Which of the following statements regarding aqueous humour is correct?
Your Answer: It only fills the anterior chamber of the eye
Correct Answer: Is the only source of nutrients for the lens of the eye
Explanation:The aqueous humour is a transparent, watery fluid similar to plasma, but containing low protein concentrations. It is secreted from the ciliary epithelium and fills both the anterior and the posterior chambers of the eye. It maintains the intraocular pressure and inflates the globe of the eye. It is this hydrostatic pressure which keeps the eyeball in a roughly spherical shape and keeps the walls of the eyeball taut. It provides nutrition (e.g. amino acids and glucose) for the avascular ocular tissues; posterior cornea, trabecular meshwork, lens, and anterior vitreous. It may serve to transport ascorbate into the anterior segment to act as an antioxidant agent. The presence of immunoglobulins indicate its role in immune response to defend against pathogens.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 4
Correct
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Which of these laboratory findings will indicate a fetal neural tube defect when done between 15 and 20 weeks of pregnancy?
Your Answer: Increased alpha-fetoprotein
Explanation:Maternal serum screening during the second trimester is a non-invasive way of identifying women at increased risk of having children with a neural tube defect and should be offered to all pregnant women. The results are most accurate when the sample is taken between 15 and 20 weeks of gestation. Elevated levels of alpha-fetoprotein suggest open spina bifida, anencephaly, risk of pregnancy complications, or multiple pregnancy.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 5
Correct
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The muscle that depresses the glenoid fossa directly is the:
Your Answer: Pectoralis minor
Explanation:Situated at the upper part of the thorax beneath the pectoralis major, is a thin pectoralis minor, triangular muscle. It originates from the third, fourth and fifth ribs, near the cartilage and from the aponeurosis which covers the intercostals. These fibres move upwards and laterally to join and form a flat tendon. This is inserted into the medial border and upper surface of the coracoid process of the scapula. Through this medial anterior thoracic nerve, fibres from the pectoralis minor are received from the eighth cervical and first thoracic nerves. This pectoralis minor pushes down on the point of the shoulder (glenoid fossa), drawing the scapula downward and medially towards the thorax which throws the inferior angle backwards.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 6
Correct
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Which of these structures does NOT pass posterior to the medial malleolus?
Your Answer: Saphenous vein
Explanation:The saphenous vein passes anterior to the medial malleolus. The structures passing posterior, from nearest to furthest include: tibial, posterior tendon, flexor digitorum longus tendon, posterior tibial artery, posterior tibial vein, posterior tibial nerve and the flexor hallucis longus tendon.
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This question is part of the following fields:
- Anatomy
- Lower Limb
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Question 7
Correct
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A 70-year old man who is suspected to have a perforated colonic diverticulum is explored in theatre through a midline incision. This incision will be through the:
Your Answer: Linea alba
Explanation:The linea alba is the point where this incision was made. It is a tendinous raphe in the midline of the abdomen extending between the xiphoid process and the symphysis pubis. It is placed between the medial borders of the recti and is formed by the blending of the aponeuroses of the external and internal obliques and transversi.
The linea aspera is a vertical ridge on the posterior surface of the femur.
The arcuate line is the inferior border of the posterior rectus sheath behind the rectus abdominis muscle.
The semilunar line is the lateral margin of the rectus abdominis.
The iliopectineal line is a line on the pelvic bones formed by the arcuate line of the ilium and the pectineal line of the pubis.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 8
Correct
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When a penile tumour invades the subepithelial connective tissue of the penis, what is its stage?
Your Answer: T1
Explanation:The TNM staging used for penile cancer is as follows:
TX: primary tumour cannot be assessed
T0: primary tumour is not evident
Tis: carcinoma in situ is present
Ta: non-invasive verrucous carcinoma is present
T1: tumour is invading subepithelial connective tissue
T2: tumour is invading the corpora spongiosum or cavernosum
T3: tumour invading the urethra or prostate
T4: tumour invading other adjacent structures.
In this case, the patient has a T1 tumour.
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This question is part of the following fields:
- Pathology
- Urology
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Question 9
Correct
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A 30 year-old male patient sustained a sharp blow to the right side of the head, over the temporal region during a vehicular accident. This resulted to the rupture of the principal artery that supplies the meninges. Which artery is affected?
Your Answer: Middle meningeal artery
Explanation:The middle meningeal artery is typically the third branch of the first part of the maxillary artery, one of the two terminal branches of the external carotid artery. After branching off the maxillary artery in the infratemporal fossa, it runs through the foramen spinosum to supply the dura mater and the calvaria. The middle meningeal artery is the largest of the three (paired) arteries that supply the meninges, the others being the anterior meningeal artery and the posterior meningeal artery. The anterior branch of the middle meningeal artery runs beneath the pterion. It is vulnerable to injury at this point, where the skull is thin. Rupture of the artery may give rise to an epidural hematoma .An injured middle meningeal artery is the most common cause of an epidural hematoma.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 10
Correct
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Which of the given options best describes the metabolic changes which occur following a severe soft tissue injury sustained after a PVA?
Your Answer: Mobilisation of fat stores
Explanation:The following metabolic responses occur following trauma as part of a coping mechanism for the additional stress. These include acid base changes (metabolic acidosis or alkalosis), decrease urine output and osmolality, reduced basal metabolic rate (BMR), gluconeogenesis with amino acid breakdown and shunting, hyponatraemia as a result of impaired functioning of sodium pumps, hypoxic injury, coagulopathies, decreased immunity, increase extracellular fluid and hypovolemic shock, increase permeability leading to oedema, break down and mobilization of fat reserves, pyrexia and reduced circulating levels of albumin.
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This question is part of the following fields:
- Cell Injury & Wound Healing
- Pathology
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Question 11
Incorrect
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Which of the following structures is derived from the dorsal mesogastrium of the stomach during the development of the gut?
Your Answer: Lesser omentum
Correct Answer: Greater omentum
Explanation:In a developing foetus, the stomach has two mesogastria from which most of the abdominal ligaments develop. These two mesogastria are the; ventral mesogastrium and the dorsal mesogastrium. During the embryological development of the gut, different organs develop in each mesogastrium; the spleen and pancreas in the dorsal mesogastrium while the liver in the ventral mesogastrium (with their associated ligaments). In the dorsal mesogastrium the following structures develop; the greater omentum (containing the gastrophrenic ligament and the gastrocolic ligament), gastrosplenic ligament, mesentery, splenorenal ligament and phrenicocolic ligament. The structures that develop from the ventral mesogastrium include the; lesser omentum (containing the hepatoduodenal ligament and the hepatogastric ligament) in association with the liver; the coronary ligament (left triangular ligament, right triangular ligament and hepatorenal ligament) and the falciform ligament (round ligament of liver and ligamentum venosum within).
There are also folds that develop from the dorsal mesogastrium which include; umbilical folds, supravesical fossa, medial inguinal fossa, lateral umbilical fold, lateral inguinal fossa and Ileocecal fold.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 12
Incorrect
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A 35 year-old woman is undergoing thyroidectomy. The external laryngeal nerve may be injured whilst ligating this artery during the procedure due to its close relationship?
Your Answer: Inferior thyroid artery
Correct Answer: Superior thyroid artery
Explanation:The superior thyroid artery arises from the external carotid artery just below the level of the greater cornu of the hyoid bone and ends in the thyroid gland. This artery must be ligated at the thyroid when conducting a thyroidectomy. If the artery is severed, but not ligated, it will bleed profusely. In order to gain control of the bleeding, the surgeon may need to extend the original incision laterally to ligate the artery at its origin at the external carotid artery. The external laryngeal branch of the superior laryngeal nerve courses in close proximity to the superior thyroid artery, making it at risk for injury during surgery.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 13
Correct
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During a laparoscopic inguinal hernia repair, the surgeon finds an artery in the extraperitoneal connective tissue (preperitoneal fat) that courses vertically and just medial to the bowel as the bowel passes through the abdominal wall. Which artery is this?
Your Answer: Inferior epigastric
Explanation:The inferior epigastric artery comes from the external iliac artery just above the inguinal ligament to curve forward in the subperitoneal tissue and then ascend obliquely along the medial margin of the deep inguinal ring. It continues to ascend between the rectus abdominis and the posterior lamella of its sheath after piercing the fascia transversalis and passing anterior to the linea semicircularis. Finally it gives off numerous branches that anastomose above the umbilicus with the superior epigastric branch of the internal mammary artery and with the lower intercostal arteries. As this artery ascends obliquely upwards from its origin it lies along the lower medial margins of the deep inguinal ring and posterior to the start of the spermatic cord. It is found in the preperitoneal fat of the abdomen lying just superficial to the peritoneum and forms the lateral umbilical fold. Hernias that pass lateral to this are indirect and medial to this, direct hernias.
The deep circumflex artery travels along the iliac crest on the inner surface of the abdominal wall. It is very lateral to the abdominal wall and hernias would pass medial to it.
The superficial circumflex iliac, superficial epigastric, superficial external pudendal arteries are all superficial arteries found in the superficial fascia.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 14
Incorrect
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A ‘claw hand’ is usually associated with injury to which of the following nerves?
Your Answer: Median nerve
Correct Answer: Ulnar nerve
Explanation:A ‘claw hand’ is associated with injury to the ulnar nerve at the wrist affecting the interossei, lumbricals and hypothenar muscles of the hand. It is characterized by hypothenar eminence wasting, hyperextended metacarpophalangeal joints and flexed interphalangeal joints.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 15
Correct
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The circle of Willis is an arterial anastomosis in the base of the brain and is one of the cerebrovascular safeguards in the brain. Where is the circle of Willis contained?
Your Answer: Cisterna basalis
Explanation:Cisterns refers to a system of intercommunicating pools formed by the subarachnoid space at the base of the brain and around the brainstem. Cisterna basalis/basal cistern (interpeduncular cistern) is found at the base of the brain between the two temporal lobes and it contains the arterial circle of Willis. The lumbar cistern is contained in the spinal canal while the foramen magna refers to the opening at the base of the skull though which the spinal cord enters into the skull.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 16
Correct
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A 20-year-old woman had profuse watery diarrhoea for 2 days. She felt dizzy and weak, and thus decided to seek medical attention. At the emergency room her BP was 80/60 mmHg with a pulse of 118/min. What is the most appropriate intravenous treatment that should be given?
Your Answer: Isotonic saline
Explanation:Normal saline is typically the first fluid used when hypovolemia is severe enough to threaten the adequacy of blood circulation. It is isotonic and has long been believed to be the safest fluid to give quickly in large volumes.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 17
Correct
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Which of the following conditions is characterized by generalised oedema due to effusion of fluid into the extracellular space?
Your Answer: Anasarca
Explanation:Anasarca (or ‘generalised oedema’) is a condition characterised by widespread swelling of the skin due to effusion of fluid into the extracellular space. It is usually caused by liver failure (cirrhosis of the liver), renal failure/disease, right-sided heart failure, as well as severe malnutrition/protein deficiency.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 18
Correct
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A patient is diagnosed with a tumour of the parotid gland. During surgical removal of the gland, which artery is vulnerable to injury?
Your Answer: External carotid artery
Explanation:The external carotid artery is a major artery of the head and neck. It arises from the common carotid artery when it splits into the external and internal carotid artery. It supplies blood to the face and neck. The external carotid artery begins opposite the upper border of the thyroid cartilage and, taking a slightly curved course, passes upward and forward and then inclines backward to the space behind the neck of the mandible, where it divides into the superficial temporal and internal maxillary arteries. It rapidly diminishes in size in its course up the neck, owing to the number and large size of the branches given off from it. At its origin, this artery is more superficial and placed nearer the midline than the internal carotid and is contained within the carotid triangle. The external carotid artery is covered by the skin, superficial fascia, platysma, deep fascia and anterior margin of the sternocleidomastoid. It is crossed by the hypoglossal nerve, by the lingual, ranine, common facial and superior thyroid veins; and by the digastric and stylohyoid; higher up it passes deeply into the substance of the parotid gland, where it lies deep to the facial nerve and the junction of the temporal and internal maxillary veins. It is here that it is in danger during surgery of the parotid gland.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 19
Incorrect
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Two boys were playing when one of them brought the forearm of the other behind his back. This resulted in a stretching of the lateral rotator of the arm. Which of the following muscles was most likely to have been involved?
Your Answer: Latissimus dorsi
Correct Answer: Infraspinatus
Explanation:There are two lateral rotators of the arm, the infraspinatus and the teres minor muscles. The infraspinatus muscle receives nerve supply from C5 and C6 via the suprascapular nerve, whilst the teres minor is supplied by C5 via the axillary nerve.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 20
Correct
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A 35-year-old ultra marathon runner becomes severely dehydrated and collapses. This patient most likely has:
Your Answer: Decreased baroreceptor firing rate
Explanation:Baroreceptors are sensors located in the blood vessels of all vertebrate animals. They sense the blood pressure and relay the information to the brain, so that a proper blood pressure can be maintained. Acute dehydration results in decreased plasma volume and increased plasma osmolarity, since more water than salt is lost in sweat. The decrease in plasma volume leads to an inhibition of the baroreceptors and a lower firing rate. The increase in plasma osmolarity leads to increased ADH secretion and high plasma ADH levels, which increases water permeability of collecting duct cells. Therefore more water is reabsorbed by the kidneys and renal water excretion is low.
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This question is part of the following fields:
- Physiology
- Renal
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Question 21
Correct
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Rapid eye movement (REM) sleep is likely to be affected by a lesion in the:
Your Answer: Pons
Explanation:Rapid eye movement (REM) sleep is also known as paradoxical sleep, as the summed activity of the brain’s neurons is quite similar to that during waking hours. Characterised by rapid movements of the eyes, most of the vividly recalled dreams occur during this stage of sleep. The total time of REM sleep for an adult is about 90–120 min per night.
Certain neurones in the brainstem, known as REM sleep-on cells, which are located in the pontine tegmentum, are particularly active during REM sleep and are probably responsible for its occurrence. The eye movements associated with REM are generated by the pontine nucleus with projections to the superior colliculus and are associated with PGO (pons, geniculate, occipital) waves.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 22
Correct
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An ultrasound report of a 35-year old female patient revealed that she had cancer of the pancreas and presented with subsequent severe obstructive jaundice. In which part of this was woman's pancreas was the tumour most likely located?
Your Answer: Head
Explanation:The pancreas is divided into five parts; the head, body, neck, tail, and the uncinate process. Of the five parts, tumours located at the head of the pancreas in most instances cause obstruction of the common bile duct more often than tumours in the other parts of the pancreas. This is because the common bile duct passes through the head of the pancreas from the gallbladder and the liver (it is formed where the cystic and the hepatic bile duct join) to empty bile into the duodenum. This biliary obstruction leads to accumulation of bile in the liver and a consequent bilirubinaemia (raised levels of blood bilirubin). This results in jaundice. The pancreas is not divided into lobes.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 23
Correct
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Injury to this nerve may result in loss of sensation of the mandibular teeth and bone:
Your Answer: Inferior alveolar nerve
Explanation:The inferior alveolar nerve (sometimes called the inferior dental nerve) is a branch of the mandibular nerve, which is itself the third branch of the trigeminal nerve. The inferior alveolar nerves supply sensation to the lower teeth of the mandible.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 24
Incorrect
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A middle aged man presented in OPD with a low grade fever and a persistent cough. His blood smear showed an increase in cells with large bi-lobed nuclei. Which of these cells represent the one seen on the smear?
Your Answer: Neutrophils
Correct Answer: Monocytes
Explanation:Monocytes are white cells that protect the body against harmful pathogens. They are mobile and are produced in the bone marrow, mature there and circulate in the blood for about 1-3 days, where they enter the tissues and transform into macrophages. They are characteristically identified by their large bi-lobed nuclei.
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This question is part of the following fields:
- Inflammation & Immunology
- Pathology
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Question 25
Correct
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The surgical registrar is doing an exploratory laparotomy on a 35 year old lady of African descent with tuberculous of the abdomen and suspected perforation. The small bowel is matted due to adhesions and it is difficult to differentiate the ileum from the jejunum. Which of the following features is typical of the jejunum?
Your Answer: It has sparse aggregated lymph nodules
Explanation:The jejunum has a wider diameter, is thicker and more vascularized, hence of a deeper colour compared to the ileum. The valvulae conniventes (circular folds) of its mucous membranes are large and thick and its villi are larger than those in the ileum. The jejunum also has sparse aggregates of lymph nodules and most of its part occupies the umbilical and left iliac regions whilst the ileum is mostly in the umbilical, hypogastric, right iliac and pelvic regions.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 26
Correct
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A 29-year-old woman presents to the doctor complaining of cough, shortness of breath, fever and weight loss. Chest X-ray revealed bilateral hilar and mediastinal lymph node enlargement and bilateral pulmonary opacities. Non-caseating granulomas were found on histological examination. The most likely diagnosis is:
Your Answer: Sarcoidosis
Explanation:Sarcoidosis is an inflammatory disease of unknown aetiology that affects multiple organs but predominantly the lungs and intrathoracic lymph nodes. Systemic and pulmonary symptoms may both be present. Pulmonary involvement is confirmed by a chest X-ray and other imaging studies. The main histological finding is the presence of non-caseating granulomas.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 27
Correct
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In what form are fats primarily transported in the body?
Your Answer: Free fatty acids
Explanation:Fat is mainly transported in the body as free fatty acids. Once out of the adipose cell, the free fatty acids get ionized and combine with albumin.
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This question is part of the following fields:
- Gastroenterology
- Physiology
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Question 28
Correct
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After a cerebral infarction, which of these histopathogical findings is most likely to be found?
Your Answer: Liquefactive necrosis
Explanation:The brain has a high lipid content and typically undergoes liquefaction with ischaemic injury, because it contains little connective tissue but high amounts of digestive enzymes.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 29
Correct
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An old man presented with atrophy of the thenar eminence despite the sensation over it still being intact. What is the injured nerve in this case?
Your Answer: Median nerve
Explanation:Atrophy of the thenar muscles means injury to the motor supply of these muscles. The nerve that sends innervation to it is the median nerve. But the median nerve does not provide sensory innervation to the overlying skin so sensation is spared.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 30
Correct
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A 45-year old farmer was referred to the surgical clinic with complaints of pain in his right hypochondrium. Investigations confirmed the diagnosis of hepatocellular carcinoma with malignant ascites. According to you, what is the most likely cause of HCC in this patient?
Your Answer: Aflatoxin
Explanation:Aflatoxins are naturally occurring toxins produced by the Aspergillus fungus (most often, A. flavus and A. parasiticus). These organisms are common and their native habitat is soil, decaying vegetation and grains. They can contaminate the grain before harvest or after storage, more likely in high-humidity (at least 7%) or high temperature environment of after stressful conditions like drought. Aflatoxins are mycotoxins and also carcinogenic. They get metabolized in the liver to an epoxide, aflatoxin M1. High exposure can lead to acute necrosis, cirrhosis or liver carcinoma. These substances can cause haemorrhage, acute liver damage, oedema, and alteration in digestion, absorption and/or metabolism of nutrients. Although humans are susceptible to these toxins like all other animals, they have a high tolerance level and hence, rarely develop acute aflatoxicosis. However, children are particularly susceptible to exposure leading to growth impairment and delayed development. Chronic exposure carries a high risk of hepatic cancer, due to intercalation of its metabolite aflatoxin M1 into the DNA and alkylation of the bases because of its epoxide moiety.
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This question is part of the following fields:
- Gastrointestinal; Hepatobiliary
- Pathology
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Question 31
Correct
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Lack of findings in the bladder but presence of atypical epithelial cells in urinalysis is most often associated with which of the following conditions?
Your Answer: Transitional cell carcinoma of renal pelvis
Explanation:The presence of atypical cells in urinalysis without findings in the bladder suggests a lesion located higher up, most probably in ureters or renal pelvis. Transitional cell cancer of the renal pelvis is a disease in which malignant cells form in the renal pelvis and is characterised by the presence of abnormal cells in urine cytology.
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This question is part of the following fields:
- Pathology
- Renal
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Question 32
Correct
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You observe a procedure to harvest the left internal thoracic (mammary) artery to be used as a graft for coronary artery bypass surgery. The left internal thoracic artery is mobilised from the inside of the chest wall and divided near the caudal end of the sternum. After dividing the internal thoracic artery at its distal end, the specialist registrar asks you to name the artery that will now have increased blood supply so that adequate blood flow is maintained to the rectus abdominis on the left side. What would your answer be?
Your Answer: Inferior epigastric artery
Explanation:The rectus abdominis muscle is supplied by the superior epigastric artery which is a branch of the internal thoracic artery. If the internal thoracic artery is thus ligated, blood would no longer flow to it. However, the superior epigastric artery communicates with the inferior epigastric artery (a branch of the external iliac artery). This means that blood could flow from the external iliac, to the inferior epigastric, to the superior epigastric to the rectus abdominis.
The superficial circumflex iliac artery and the superficial epigastric are two superficial branches of the femoral artery and do not supply the deep branches of the abdomen.
The deep circumflex iliac artery travels along the iliac crest on the inner surface of the abdominal wall; being too lateral it doesn’t supply blood to the rectus abdominis.
The distal portions of the umbilical arteries are obliterated in adults to form the medial umbilical folds.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 33
Correct
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Whilst snorkelling, a 30-year old gentleman has the respiratory rate of 10/min, tidal volume of 550 ml and an effective anatomical dead space of 250 ml. Which of the following will bring about a maximum increase in his alveolar ventilation?
Your Answer: A 2x increase in tidal volume and a shorter snorkel
Explanation:Alveolar ventilation = respiratory rate × (tidal volume − anatomical dead space volume). Increase in respiratory rate simply causes movement of air in the anatomical dead space, with no contribution to the alveolar ventilation. By use of a shorter snorkel, the effective anatomical dead space will decrease and will cause a maximum rise in alveolar ventilation along with doubling of tidal volume.
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This question is part of the following fields:
- Physiology
- Respiratory
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Question 34
Incorrect
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What's the nodal stage of a testicular seminoma if several lymph nodes between 2cm and 5cm are found?
Your Answer: N3
Correct Answer: N2
Explanation:According to the American Joint Committee on Cancer (AJCC) 2002 guidelines, the nodal staging of testicular seminoma is the following:
N0: no regional lymph node metastases
N1: metastasis with lymph nodes 2 cm or less in their greatest dimension or multiple lymph nodes, none more than 2 cm
N2: metastasis with lymph nodes greater than 2 cm but not greater than 5 cm in their greatest dimension, or multiple lymph nodes, any one mass greater than 2 cm, but not more than 5 cm
N3: metastasis with lymph nodes greater than 5 cm in their greatest dimension.
The patient in this case has N2 testicular seminoma. This TNM staging is extremely important because treatment options are decided depending on this classification.
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This question is part of the following fields:
- Pathology
- Urology
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Question 35
Correct
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Whipple's procedure involves mobilizing the head of the pancreas. As the surgeon does this, he must be careful to avoid injury to a key structure that is found lying behind the head of the pancreas. Which vital structure is this?
Your Answer: Common bile duct
Explanation:The posterior relations of the head of the pancreas include: the inferior vena cava, the common bile duct, the renal veins, the right crus of the diaphragm and the aorta.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 36
Incorrect
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Renin is secreted by pericytes in the vicinity of the afferent arterioles of the kidney from the juxtaglomerular cells. Plasma renin levels are decreased in patients with:
Your Answer: Heart failure
Correct Answer: Primary aldosteronism
Explanation:Primary aldosteronism, also known as primary hyperaldosteronism or Conn’s syndrome, is excess production of the hormone aldosterone by the adrenal glands resulting in low renin levels. Most patients with primary aldosteronism (Conn’s syndrome) have an adrenal adenoma. The increased plasma aldosterone concentration leads to increased renal Na+ reabsorption, which results in plasma volume expansion. The increase in plasma volume suppresses renin release from the juxtaglomerular apparatus and these patients usually have low plasma renin levels. Salt restriction and upright posture decrease renal perfusion pressure and therefore increases renin release from the juxtaglomerular apparatus. Secondary aldosteronism is due to elevated renin levels and may be caused by heart failure or renal artery stenosis.
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This question is part of the following fields:
- Physiology
- Renal
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Question 37
Correct
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A 24-year old patient diagnosed with a direct inguinal hernia was scheduled for surgery to have the hernia repaired. The hernia was discovered to be protruding through the Hesselbach's triangle (inguinal triangle). Which of the following blood vessels that is a branch of the external iliac artery forms the lateral border of this triangle?
Your Answer: Inferior epigastric
Explanation:The inguinal triangle is formed by the following structures; inguinal ligament at the base; inferior epigastric vessels laterally and the lateral border of the rectus sheath medially. This triangle (also known as Hesselebach’s triangle) is where direct inguinal hernias protrude. The inferior epigastric artery is this the branch of the external iliac artery being referred to. All the other blood vessels are branches of the internal iliac artery.
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This question is part of the following fields:
- Anatomy
- Pelvis
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Question 38
Correct
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A 20-year old involved in a brawl was stabbed in the anterior chest in a structure that is in close proximity to where the first rib articulates with the sternum. What is the structure that was most likely injured?
Your Answer: Sternoclavicular joint
Explanation:The first rib articulates with the sternum right below the sternoclavicular joint.
The sternal angle articulates with the costal cartilage of the second rib.
The nipple is found between the fourth and the fifth ribs, in the fourth intercostal space.
The xiphoid process is located right below the point of articulation of the costal cartilage of rib 7 with the sternum.
The root of the lung is the part of the lung where neurovascular structures enter and leave the lung.
Acromioclavicular joint is the point of articulation between the acromion process and the clavicle, near the shoulder.
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This question is part of the following fields:
- Anatomy
- Thorax
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Question 39
Correct
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Painful erections along with deviation of the penis to one side when erect are seen in which of the following conditions?
Your Answer: Peyronie’s disease
Explanation:Peyronie’s disease leads to development of fibrous plaques in the penile soft tissue and occurs in 1% of men, most commonly affecting white males above 40 years age. It is a connective tissue disorder named after a French surgeon, François de la Peyronie who first described it. Symptoms include pain, hard lesions on the penis, abnormal curvature of erect penis, narrowing/shortening, painful sexual intercourse and in later stages, erectile dysfunction. 30% cases report fibrosis in other elastic tissues such as Dupuytren’s contractures of the hand. There is likely a genetic predisposition as increased incidence is noted among the male relatives of an affected individual.
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This question is part of the following fields:
- Pathology
- Urology
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Question 40
Correct
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A 7-year-old girl is given cephalexin to treat an infection and develops hives, with localised facial oedema. Which of the following conditions will cause localised oedema?
Your Answer: Angio-oedema
Explanation:Angio-oedema, is the rapid swelling of the skin, mucosa and submucosal tissues. The underlying mechanism typically involves histamine or bradykinin. The version related to histamine is to due an allergic reaction to agents such as insect bites, food, or medications. The version related to bradykinin may occur due to an inherited C1 esterase inhibitor deficiency, medications e.g. angiotensin converting enzyme inhibitors, or a lymphoproliferative disorder.
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This question is part of the following fields:
- Physiology
- Renal
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Question 41
Correct
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A man came to the hospital complaining of a sensation of pins and needles in the dorsum of the thumb and digits 1 and 2. On further examination they found that he had weakness in wrist dorsiflexion and finger extension. Which nerve do you think is injured in this case?
Your Answer: Radial
Explanation:The radial nerve can be injured in multiple sites along its course in the upper limb, and each site has its own presentation. The major complaint is wrist drop which if high above the elbow, can cause numbness of the forearm and hand. It can last for several days or weeks. The most common site of compression for the radial nerve is at the proximal forearm in the area of the supinator muscles.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 42
Incorrect
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A 62-year-old male smoker, presented with shortness of breath, chronic cough and haemoptysis over the last three months. He has developed a fat pad in the base of his neck, rounded face, acne and osteoporosis. Which of the following is the most likely pulmonary disease that is causing these symptoms and findings?
Your Answer: Squamous cell carcinoma
Correct Answer: Small-cell anaplastic carcinoma
Explanation:Small cell lung cancer is a highly aggressive form of lung cancer. It is thought to originate from neuroendocrine cells in the bronchus called Feyrter cells and is often associated to ectopic production of hormones like ADH and ACTH that result in paraneoplastic syndromes and Cushing’s syndrome.
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This question is part of the following fields:
- Pathology
- Respiratory
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Question 43
Correct
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The rotator cuff surrounds the shoulder joint and consists of the supraspinatus, infraspinatus, subscapularis and which one other muscle?
Your Answer: Teres minor
Explanation:The correct answer is the teres minor muscle. These group of muscles play an important role in protecting the shoulder joint and keeping the head of the humerus in the glenoid fossa of the scapula. This fossa is somehow shallow and needs support to allow for the full mobility that the shoulder joint has.
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This question is part of the following fields:
- Anatomy
- Upper Limb
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Question 44
Correct
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The inferior palpebral nerve ascends behind the orbicularis oculi. What is the terminal branch of the inferior palpebral nerve?
Your Answer: Infraorbital nerve
Explanation:The inferior palpebral nerve is a branch of the maxillary nerve. It supplies the skin and conjunctiva of the lower eyelid.
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This question is part of the following fields:
- Anatomy
- Head & Neck
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Question 45
Correct
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The gynaecologist suspects that her patient has a cervical cancer. What particular test should be done on this patient to screen for cervical cancer?
Your Answer: Pap smear
Explanation:Worldwide, approximately 500,000 new cases of cervical cancer and 274,000 deaths are attributable to cervical cancer yearly. This makes cervical cancer the second most common cause of death from cancer in women. The mainstay of cervical cancer screening has been the Papanicolaou test (Pap smear).
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 46
Correct
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A 35 year old patient presenting with haematemesis, heart burn and bloody stool was diagnosed with a duodenal ulcer that had eroded the gastroduodenal artery. The patient was then rushed into theatre for an emergency procedure to control the haemorrhage. If the surgeon decided to ligate the gastroduodenal artery at its origin, which of the following arteries would most likely experience retrograde blood flow from collateral sources as a result of the ligation?
Your Answer: Right gastroepiploic
Explanation:In the stomach and around the duodenum, there are many arterial anastomoses. Ligation of the gastroduodenal artery would result in the retrograde flow of blood from the left gastroepiploic artery to the right gastroepiploic artery. The blood flows into the right gastroepiploic artery, a branch of the gastroduodenal artery from the left gastroepiploic artery that branches from the splenic artery. This retrograde blood flow is aimed at providing alternate blood flow to the greater curvature of the stomach.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 47
Correct
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Which structure holds the duodenojejunal flexure in place?
Your Answer: Suspensory ligament (of Treitz)
Explanation:The duodenum is connected to the diaphragm by the suspensory ligament called the ligament of Treitz. It is a slip of skeletal muscle from the right crus of the diaphragm and a fibromuscular band of smooth muscle from the 3rd and 4th parts of the duodenum. It is an important landmark, used to divide the gastrointestinal tract into the upper and lower parts. Contraction of this ‘ligament’ leads to opening of the duodenojejunal flexure allowing the flow of chyme.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 48
Correct
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In a splenectomy procedure, special care is emphasized on the preservation of the tail of the pancreas that is closely associated with the spleen to avoid post operative pancreatic fistula. As a general surgeon conducting a splenectomy where are you most likely to find the tail of the pancreas in the abdominal cavity?
Your Answer: Splenorenal ligament
Explanation:The tail of the pancreas is the only intraperitoneal part of the pancreas and is found contained in the splenorenal ligament of the peritoneal cavity. The splenorenal ligament is derived from the peritoneum where the wall of the general peritoneal cavity connects to the omental bursa between the spleen and the left kidney. This ligament contains the splenic vessels and the tail of the pancreas.
The gastrocolic ligament stretches from the greater curvature of the stomach to the transverse colon, connecting the two.
The gastrosplenic ligament is derived from the greater omentum and is the structure that connects the stomach to the hilum of the spleen. The gastrosplenic ligament continues from the splenic flexure of the colon to the diaphragm and acts as a support to the spleen.
The transverse colon is connected to the abdominal wall by the mesocolon ligament.
The falciform ligament on the other hand, attaches the liver to the ventral wall of the abdomen.
The hepatoduodenal ligament connects the porta hepatis of the liver to the superior part of the duodenum.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 49
Incorrect
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A surgeon ligates the left superior suprarenal artery whilst preforming a left adrenalectomy. Where does the left superior suprarenal artery originate?
Your Answer: Abdominal aorta
Correct Answer: Left inferior phrenic artery
Explanation:The superior suprarenal arteries arises from the inferior phrenic artery on either side.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 50
Incorrect
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A 50-year old gentleman who suffered a stroke was brought to the emergency department by his relatives. The patient however denied the presence of paralysis of his left upper and lower limbs. What is the most likely site of the lesion in this patient?
Your Answer: Right postcentral gyrus
Correct Answer: Right posterior parietal cortex
Explanation:A large injury to the non-dominant parietal cortex can make the patient neglect or refuse to acknowledge the presence of paralysis on the contralateral side. This can also involve the perception of the external world. Smaller injuries in this area which involve the precentral gyrus (primary motor cortex) or postcentral gyrus (primary sensory cortex) cause contralateral spastic paralysis or contralateral loss of tactile sensation respectively. A lesion in posterior inferior gyrus of the dominant frontal lobe results in motor aphasia. Involvement of the posterior superior gyrus of the dominant frontal lobe produces sensory aphasia.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 51
Incorrect
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A 7-year-old boy is diagnosed with metabolic acidosis as a result of severe dehydration. Which of the following conditions is most likely to cause severe dehydration and metabolic acidosis?
Your Answer: Severe persistent vomiting
Correct Answer: Severe diarrhoea
Explanation:Diarrhoea is defined as having three or more loose or liquid stools per day, or as having more stools than is normal for that person. Severe diarrhoea, causing fluid loss and loss of bicarbonate, will result in marked dehydration and metabolic acidosis.
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This question is part of the following fields:
- Fluids & Electrolytes
- Physiology
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Question 52
Correct
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A 25-year-old female had a painful abdomen and several episodes of vomiting. She was severely dehydrated when she was brought to the hospital. Her ABG showed a pH 7.7, p(O2) 75 mmHg, p(CO2) 46 mmHg and bicarbonate 48 mmol/l. The most likely interpretation of this ABG report would be:
Your Answer: Metabolic alkalosis
Explanation:Metabolic alkalosis is a primary increase in bicarbonate (HCO3−) with or without compensatory increase in carbon dioxide partial pressure (Pco2); pH may be high or nearly normal. Metabolic alkalosis occurs as a consequence of a loss of H+ from the body or a gain in HCO3 -. In its pure form, it manifests as alkalemia (pH >7.40). As a compensatory mechanism, metabolic alkalosis leads to alveolar hypoventilation with a rise in arterial carbon dioxide tension p(CO2), which diminishes the change in pH that would otherwise occur. Normally, arterial p(CO2) increases by 0.5–0.7 mmHg for every 1 mmol/l increase in plasma bicarbonate concentration, a compensatory response that occurs very rapidly. If the change in p(CO2) is not within this range, then a mixed acid–base disturbance occurs. Likewise, if the increase in p(CO2) is less than the expected change, then a primary respiratory alkalosis is also present. However an elevated serum bicarbonate concentration can also occur due to a compensatory response to primary respiratory acidosis. A bicarbonate concentration greater than 35 mmol/l is almost always caused by metabolic alkalosis (as is the case in this clinical scenario). Calculation of the serum anion gap can also help to differentiate between primary metabolic alkalosis and the metabolic compensation for respiratory acidosis. The anion gap is frequently elevated to a modest degree in metabolic alkalosis because of the increase in the negative charge of albumin and the enhanced production of lactate. However, the only definitive way to diagnose metabolic alkalosis is by performing a simultaneous blood gases analysis, which reveals elevation of both pH and arterial p(CO2) and increased calculated bicarbonate.
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This question is part of the following fields:
- Fluids & Electrolytes
- Pathology
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Question 53
Correct
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Calculate the cardiac output in an adult male with the following parameters:
Heart rate 70 beats/min
Arterial [O2] 0.24 ml O2/min
Venous [O2] 0.16 ml O2/mi
Whole body O2 consumption 500 ml/min
Pulmonary diastolic pressure 15 mmHg
Pulmonary systolic pressure 25 mmHg
Wedge pressure 5 mmHg.Your Answer: 6.25 l/min
Explanation:As per Fick’s principle, VO2 = (CO × CAO2) – (CO × CVO2) where VO2 = oxygen consumption, CO = cardiac output, CAO2 = oxygen concentration of arterial blood and CVO2 = oxygen concentration of venous blood. Thus, CO = VO2/CAO2– CVO2, CO = 500/0.24 – 0.16, CO = 500/0.8, CO = 6.25 l/min.
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This question is part of the following fields:
- Cardiovascular
- Physiology
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Question 54
Correct
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A 66-year-old man complains of constant headaches. On physical examination, the only relevant sign is a dark brown mole located on left his arm which has grown in size over the years and is itchy and painful. A MRI of the brain revealed a solitary lesion at the grey-white junction in the right frontal lobe, without ring enhancement. This lesion is most likely to be:
Your Answer: Metastatic carcinoma
Explanation:The location of the mass at the grey–white junction is typical of a metastasis. The most frequent types of metastatic brain tumours originate in the lung, skin, kidney, breast and colon. These tumour cells reach the brain via the bloodstream. This patient is likely to have skin cancer, which caused the metastatic brain tumour.
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This question is part of the following fields:
- Neurology
- Pathology
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Question 55
Correct
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Which of the following arteries, if ligated, will most likely affect blood supply to the pancreas?
Your Answer: Superior mesenteric
Explanation:The pancreas is a glandular organ in the body that produces important hormones such as insulin and glucagon. Its blood supply is from branches of the coeliac artery, superior mesenteric artery and the splenic artery. These are the arteries that if ligated, would affect blood supply to the pancreas.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 56
Correct
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A patient with a long standing lower motor neuron lesion will have:
Your Answer: Muscle wasting
Explanation:Lower motor neurons (LMNs) connect the brainstem and spinal cord to muscle fibres. Damage to lower motor neurons is indicated by abnormal electromyographic potentials, fasciculations, paralysis, weakening and wasting of skeletal muscles.
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This question is part of the following fields:
- Neurology
- Physiology
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Question 57
Correct
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The pattern of drainage of the lymphatic and venous systems of the anterior abdominal wall is arranged around a horizontal plane above which drainage is in a cranial direction and below which drainage is in a caudal direction. Which horizontal plane is being referred to?
Your Answer: Level of the umbilicus
Explanation:The umbilicus is a key landmark for the lymphatic and venous drainage of the abdominal wall. Above it, lymphatics drain into the axillary lymph nodes and the venous blood drains into the superior epigastric vein, into the internal thoracic vein. Below it, lymphatics drain into the superficial inguinal lymph nodes while venous blood drains into the inferior epigastric vein and the external iliac vein.
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This question is part of the following fields:
- Abdomen
- Anatomy
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Question 58
Incorrect
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The specimen sent to the pathologist for examination was found to be benign. Which one of the following is most likely a benign tumour?
Your Answer: Osteogenic sarcoma
Correct Answer: Warthin’s tumour
Explanation:Warthin’s tumour is also known as papillary cystadenoma lymphomatosum. It is a benign cystic tumour of the salivary glands containing abundant lymphocytes and germinal centres. It has a slightly higher incidence in males and most likely occur in older adults aged between 60 to 70 years. This tumour is also associated with smoking. Smokers have an eight-fold greater risk in developing the tumour compared to non-smokers.
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This question is part of the following fields:
- Neoplasia
- Pathology
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Question 59
Incorrect
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Which tumour occurs in young adults, affecting the epiphyses of the bones and sometimes extending to the soft tissues?
Your Answer: Osteoid osteoma
Correct Answer: Benign giant-cell tumour
Explanation:Benign giant-cell tumours tend to affect adults in their twenties and thirties, occur in the epiphyses and can erode the bone and extend into the soft tissues. These tumours have a strong tendency to recur.
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This question is part of the following fields:
- Orthopaedics
- Pathology
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Question 60
Correct
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Which is the most common benign germ-cell tumour that could occur in a premenopausal woman?
Your Answer: Dermoid cyst
Explanation:A dermoid cyst is a teratoma of a cystic nature that contains an array of developmentally mature and solid tissues. Dermoid cysts grow slowly and this type of cystic teratoma is nearly always benign.
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This question is part of the following fields:
- Neoplasia
- Pathology
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