NMS Q&A Family Medicine

34 NMS Q&A Family MedicineExamination Answers1. The answer is A. The clusters of little yellow dots aredrusen. They have great pathological significance in thatthey signal the presence of non-exudative (age-related)macular degeneration, the most common cause of permanentblindness in the elderly. Cotton wool exudatesresemble just that larger than drusen and white as opposedto yellow and they signify diabetic retinopathy. Microaneurysmsare blood colored and the same or smaller thancotton wool exudates and are pathognomonic of diabetes.Flame hemorrhages are well named for their appearanceand signify advanced staging of hypertension. The pointsof crossings of arterioles and venules are notching causedby traction on the venules by the thicker-walled arteriolesas they deform with sclerotic change.2. The answer is D. Fragility of the zonules holding thelens capsule, that is, the guy wires that suspend the lenscapsule containing the lens. This occurs with the conditioncalled the pseudo-exfoliation syndrome or simply exfoliationsyndrome. It consists of proteinaceous materialthat escapes from the iris and appears to clog up the canalsof Schlemm impeding reabsorption of the aqueous fluidin the anterior chamber. That is not the entire explanationof the pathophysiology, however, because the glaucomawith which it is associated is of low pressure (thus, thevignette). It occurs predominantly in people of Scandinaviandescent. The largest database on the condition comesfrom Iceland. During lens implantation on patients withthis condition, special rings may have to be inserted intothe capsule after the old lens is extracted to distribute thetension more evenly among zonules if some have begunthe rupturing process during the procedure. One messageto the primary care physician is that not all destructiveglaucoma is characterized by high intraocular pressure.3. The answer is C. Peripheral loss of vision in a curtaintype of blockage, as opposed to central loss, is typical ofretinal detachment. Central visual loss occurs in opticneuritis or macular degeneration. Homonymous scotomasare always due to central lesions. Those that involvethe right field of both visual fields would occur through alesion of the left optic radiation or the left visual projectionarea of the occipital cortex. Diplopia is a result ofpathology other than retinal function. Tearing is causedby irritation of anterior structures such as corneae, conjunctivae,or sclerae and also may be a response to painand irritation associated with iritis and acute glaucoma,among other problems.4. The answer is A. Given the history, it is likely that thepatient has had a serous type of retinal detachment. Thisis brought about by effusion of serum behind the retina,secondary to uncontrolled disease states such as hypertensionor uveitis. Treatment consists of medical controlof the underlying disease (e.g., labetalol, perhaps combinedwith a thiazide diuretic in an Africa-American) andusually results in complete recovery of vision. However,most primary care physicians would make early judiciousinquiry of an ophthalmologist as they begin to control thehypertension (as in this case). A second type of detachmentis tractional retinal detachment and is due tointraocular fibrotic processes caused by previous hemorrhage.Treatment consists of surgical disengagement ofthe scar tissue from the retina by a trained ophthalmologist.The third type is the most common and is calledrhegmatogenous detachment, related to initial detachmentof the vitreous from the retina. One-fourth of thepopulation will experience this condition between the agesof 61 and 70 years. At this stage, the symptoms are mild,consisting of an increased frequency of vitreous floaters.However, 15% of people with vitreous detachment progressto develop a retinal flap or tear or a hole. Besides therisk factor of age, rhegmatogenous retinal detachmentoccurs more often in myopic individuals and in those whohave undergone cataract removal. The word rhegmatogenousis derived from the Greek word for rupture.Slit-lamp examinations are not normally expected ofprimary care physicians. Intravenous mannitol is anaccepted therapeutic modality for acute angle closureglaucoma. Acute glaucoma is characterized by intraocularpain and ipsilateral mid-position fixed pupil. A magneticresonance image of the head would be indicated for suspicionof vascular accident or neoplastic disease, neitherof which is suggested by the findings given. A carotidartery duplex Doppler study would be indicated for suspicionof visual disturbance that is due to carotid arteryinsufficiency. The latter may cause amaurosis fugax, thatis, ipsilateral transient total blindness (or partial visualcuts, such as unilateral quadrantanopsia), caused byembolism of small flakes of coagulum or ruptured plaquefrom an atherosclerotic site of carotid artery stenosis. Thispatient did not exhibit that constellation of symptoms.5. The answer is E. The patient has either a corneal abrasionor corneal laceration. Either lesion shows a greencolor in the area of abrasion, keratitis, or laceration of thecornea with cobalt blue light after instillation of fluorescein.The shape of the defect will determine whether oneis dealing with a laceration or an abrasion. If the injury isassociated with an embedded corneal foreign body, thedefect will outline the speck. The aforementioned patientmight well have a laceration or an abrasion, but it is