A 70-year-old diabetic male sees an ophthalmologist for vision trouble. He has noticed some blurry vision, and increased glare, preventing him from driving at night. He has no other complaints. Visual acuity is 20/70 in his right eye, not corrected by looking through a pinhole, and 20/25 in his left eye. Slit lamp exam shows opacifications of the lens of his right eye. Intraocular pressures are 14 mmHg and 16 mmHg in the right and left eyes respectively. The patient decides to have his cataracts surgically removed. He undergoes extracapsular cataract extraction on his right eye. The procedure is successful, with no intraoperative complications.
Which of the following would be the most likely cause of visual impairment after the procedure?
Correct Answer B: This patient had cataracts, which were removed without complications. The procedure is safe, and in the absence of other complications, prognosis is favourable. The most common cause of visual disturbance after an uneventful cataract surgery is cystoid macular edema (CME) (choice B). A breakdown of the blood-retina barrier allows fluids to accumulate in the outer plexiform and inner nuclear layers of the retina, causing decreased visual acuity. Its incidence is more common in diabetic patients. NSAIDs have been shown to be effective in the prevention of cystoid macular edema. If CME occurs, it resolves spontaneously within weeks to months in most cases, but recovery can be hastened using anti-inflammatories. CME can be diagnosed via fluorescein angiogram, or optical coherence tomography (OCT) scan.
Regarding the procedure itself, an extracapsular approach (where the lens nucleus is removed through an opening in the anterior capsule), is preferred to the intracapsular approach (where the whole lens including the posterior capsule is removed). Reasons for this preference include: smaller incision, decreased risk of adherence of vitreous to the cornea and iris, decreased incidence of CME, retinal detachment, and corneal edema, and endophthalmitis.
→ Posterior capsular tear (choice A) is incorrect. While this is one of the more common complications, it occurs intraoperatively, and can be seen by a leak of vitreous humour into the anterior chamber, requiring anterior vitrectomy.
→ Endophthalmitis (choice C) is the inflammation of the anterior and posterior parts of the eye. It is a rare complication after cataract surgery, and the risk is further decreased when the posterior capsule remains intact, since there is a smaller chance of infective material introduced into the anterior chamber during the procedure passing into the vitreous humour.
→ Retinal detachment (choice D) is a risk after cataract surgery, but the risk is less than for CME. Also, rather than causing decreased visual acuity, the symptoms of retinal detachment include flashes, floaters, and a curtain coming over the visual field.
→ Dislocation of implanted lens (choice E) is incorrect. While this is a risk after cataract surgery, it is less common than cystoid macular edema.
Key point: Cataracts are common age-related pathology of the eye. They are amenable to surgical treatment. The most common postoperative cause for decreased vision is cystoid macular edema, which typically improves over time.
A 37-year-old recreational skier is unable to lift his right arm after falling on his right side with his arm elevated. Radiographs of the right shoulder are negative, but diagnostic ultrasonography shows a complete rotator cuff tear.
Which one of the following is most accurate with regard to treatment?
Correct Answer A: Surgery for rotator cuff tears is most beneficial in young, active patients. In cases of acute, traumatic, complete rotator cuff tears, repair is recommended in less than 6 weeks, as muscle atrophy is associated with reduced surgical benefit. Advanced age and limited strength are also associated with reduced surgical benefit.
NSAIDs are used for analgesia. Their benefit has not been shown to exceed that of other simple analgesics, and the side effects profile may be higher. Corticosteroid injections will not improve a complete tear. Some experts also recommend avoiding their use in partial or complete tendon tears. Therapeutic ultrasound does not add to the benefit from range-of-motion exercises and exercises to strengthen the involved muscle groups.
A 58-year-old female presents with complaints of weight loss, fatigue, and the yellow skin, that has been progressively changing colour (more yellow) in the last few weeks. She has had an 8kg unintentional weight loss. She also says that she has felt a need to scratch all over the body because of a constant itchy feeling. She denies abdominal pain, back pain, or abdominal fullness. She is not on any special diet. She has smoked 1 pack per day for the last 30 years. Physical examination reveals a palpable but non-tender gallbladder.
Which of the following is most likely to be associated with this patient’s disease?
Correct Answer D: This patient is presenting with some non-specific constitutional symptoms that are characteristic of cancer such as unintentional weight loss and fatigue. She also complains of jaundice, which is most likely to be the cause of her unbearable pruritus. Given the Curvoisier’s sign found on physical examination (palpable but non-tender gallbladder) along with the symptoms described, her most likely diagnosis is pancreatic cancer.
Pancreatic cancer is the 4th in cancer mortality. Family history and smoking history are the most common risk factors. The head of the pancreas is the location most likely to be affected with 2/3 of pancreatic cancers found in the head of the pancreas. Migratory thrombophlebitis (choice D) also known as Trousseau’s sign of malignancy is a common nonmalignant manifestation of pancreatic cancer.
→ Muscle weakness of legs (choice A) may be seen in Lambert-Eaton Myasthenic syndrome which is a paraneoplastic syndrome of small cell lung cancer.
→ Krukenberg ovarian tumor (choice B) are metastatic disease of gastrointestinal tumors, especially gastric adenocarcinoma.
→ Elevated alpha-fetoprotein (choice C) is seen in primary liver cancer.
→ Porcelain gallbladder history (choice E) is associated with gallbladder cancer. It is a rare tumor and is more likely to present with a steady right upper quadrant pain.
Key point: Pancreatic cancer often presents with painless jaundice, unintentional weight loss, and fatigue. It is associated with Courvoisier's sign, Trousseau's sign, migratory thrombophlebitis.
A 48-year-old patient, who suffered significant brain damage, is declared brain dead. He had agreed for his organs to be donated after death.
Which of the following is true regarding the diagnosis of brain death?
Correct Answer C: The dead-donor rule requires patients to be pronounced dead before the harvest of life-sustaining organs for transplantation. The concept of brain death was developed, in part, to allow patients with serious neurologic damage to be declared dead before the occurrence of cardiopulmonary arrest. Brain death is essential to current practices of organ retrieval because it legitimates organ removal from bodies that continue to have circulation and respiration, thereby avoiding ischemic injury to the organs.
Brain death is defined as the irreversible loss of all functions of the brain, including the brainstem. The three essential findings in brain death are coma, absence of brainstem reflexes, and apnea. An evaluation for brain death should be considered in patients who have suffered a massive, irreversible brain injury of identifiable cause. The diagnosis of brain death is primarily clinical. No other tests are required if the full clinical examination, including each of two assessments of brain stem reflexes and a single apnea test, is conclusively performed. The process to make conclusive diagnosis includes:
Given the above criteria, the only correct answer among choices given is atropine increases heart rate < 5bpm (choice C). This indicates absent function of the vagus nerve and nuclei (brain stem-medulla oblongata).
→ Patient’s temperature has to be > 35°C (choice A) is incorrect. The temperature cut off is 32°C; hypothermia has to be excluded because it reduces metabolic needs significantly and a patient who appears dead below this temperature may not be actually dead.
→ Pupils need to be equal and dilated (choice B) is incorrect. When assessing the pupils to determine brain death, what should be determined is absence of pupillary reflex to direct and consensual light.; Pupils need not be equal or dilated.
→ Needs to be confirmed with an EEG (choice D) is incorrect. While EEG can confirm brain death if absence of electrical activity is documented for 30 minutes, it is not required to make the diagnosis of brain death as this diagnosis is primarily clinical.
→ Positive apnea test done at least twice (choice E) is incorrect. The apnea test need only be performed once when its results are conclusive.
Key point: Brain death is defined as the irreversible loss of all functions of the brain, including the brainstem. Vagus nerve activity indicates brainstem function and one of the criteria for diagnosing brain death is failure to increase heart rate > 5 beats per minute after atropine injection.
A 56-year-old man presents with history of right-sided breast swelling of two months' duration. On examination, the swelling is firm and tender, is present under the areola and measures 3 cm in diameter. There is no discharge from the nipple. Rest of the examination is within normal limits. He suffers from hypertension and dyslipidemia and is on ramipril, amlodipine, metoprolol, spironolactone and atorvastatin. His kidney and liver functions are within normal limits.
Which one of the following medications' discontinuation is most likely to result in resolution of the breast swelling?
Correct Answer E: Breast enlargement in men is known as gynecomastia. As described in the stem, it is firm, tender and beneath the areola. Rarely the enlargement extends beyond areola. It is more often unilateral but can also be bilateral. Gynecomastia is an endocrine disorder, thought to be caused by an altered ratio of estrogen and testosterone, due to increase in estrogen production or decrease in testosterone production or both. Physiologic gynecomastia occurs after birth and at puberty. Non-physiologic gynecomastia can be due to kidney or liver failure, or due to testicular or adrenocortical tumors or secondary to some medications.
Non-hormonal medications known to cause gynecomastia are ketoconazole, cimetidine, spironolactone (choice E) and 5-alpha-reductase inhibitors such as finasteride. Gynecomastia is a known adverse effect of spironolactone and is related to dose and duration of treatment. Spironolactone induces gynecomastia by decreasing testosterone production, increasing peripheral conversion of testosterone to estradiol, and displacing estradiol from sex hormone-binding globulin. Discontinuation of treatment results in resolution of gynecomastia.
→ Other antihypertensive medications, especially calcium channel blockers such as verapamil and amlodipine (choice A) are associated with development of gynecomastia but the incidence is highest with spironolactone.
→ Ramipril (choice D), metoprolol (choice C) and atorvastatin (choice B) are not associated with development of gynecomastia.
Key point: Gynecomastia is a known adverse effect of drugs that stimulate production of prolactin such as anti-psychotic drugs (haloperidol and risperidone) and tricyclic antidepressants.
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