17 A 57-Year-Old Male With Blurred Vision


Case 17

A 57-Year-Old Male With Blurred Vision



Steven M. Naids, Brian K. Do



A 57-year-old male with a past medical history of type 2 diabetes mellitus diagnosed 10 years prior to presentation presents for evaluation of 2 months of blurred vision in both eyes. The right eye is more bothersome than the left. He has been unable to drive for the last 2 months due to his vision. He was fitted for a new pair of glasses less than a month ago, but they have not improved his vision. There has been no associated eye pain or redness.



Why is it important to ask about eye pain and redness in association with vision loss?


It is important to ask about eye pain and redness when evaluating the etiology of vision loss because painless vision loss is most commonly associated with a process involving the more posterior portion of the eye (i.e., the retina, vitreous, choroid, and in some cases the optic nerve). Painful vision loss with redness on exam should alert you that the front of the eye (i.e., the cornea, conjunctiva, anterior sclera, iris, or ciliary body) is involved. A red eye can provide helpful information on the acuity of the inciting event and may or may not be associated with vision loss.



He denies headache, dizziness, nausea, and vomiting. He complains of a persistent mild burning sensation on the plantar surfaces of both feet for the past year. His other review of systems is negative.



Step 1


Basic Science Pearl


Sometimes, an ophthalmologist may be the first doctor that a diabetic patient presents to. Even though the focus of this case is the eye, it is important to take a complete history, including review of systems in diabetic patients. This can provide you with important clues as to the duration and control of the patient’s disease. In this case, the patient has stocking-glove neuropathy, indicating poor control or long duration of the disease. This is associated with more advanced eye disease.



The patient’s other past medical history is significant for a known 15-year history of hypertension, for which he takes lisinopril. He has been taking metformin since diagnosis and has never used insulin. He has never had surgery, including eye surgery. His family history is significant for hypertension in both parents and for myocardial infarction suffered by his father at age 65. He has a 30-pack/year history of cigarette smoking. He works long hours as a construction site supervisor and admits that his job has prevented him from following up regularly with his primary care physician.



Step 1


Basic Science Pearl


Obtaining a good social history is important in these patients. Although control of blood sugar over the duration of the disease is important, other cardiovascular risk factors such as hypertension and hyperlipidemia must be addressed. Ask patients about their diet, exercise, smoking, and alcohol habits, as modifying these can help better achieve treatment goals.



When should a diabetic patient be initially screened for diabetic retinopathy?


It is currently estimated that as of 2014, only about 60% of diabetics have a yearly screening for diabetic retinopathy. Currently, screening is recommended for type 1 diabetics 5 years after the onset of their disease. Type 2 diabetics should be screened at diagnosis and yearly thereafter.


The duration of diabetes is a major risk factor in the development of diabetic retinopathy. After 5 years, approximately 25% of type 1 patients have retinopathy. After 10 years, 60% develop retinopathy, and after 15 years, 80% will be affected.


Of type 2 patients over the age of 30 who have had diabetes for less than 5 years, 40% of those taking insulin and 24% of those not taking insulin have retinopathy. The percentages increase to 84% and 53%, respectively, when the duration has been documented for up to 19 years.


Currently, the gold standard imaging for the diagnosis and classification of diabetic retinopathy is stereoscopic color photographs using seven standard fields. However, this is very labor intensive. There is evidence that single-field fundus photographs in the hands of trained readers can serve as an effective screening tool.



The Snellen best-corrected distance visual acuity is 20/150 in the right eye and 20/50 in the left eye as measured with his glasses. A refraction done in the office does not improve his vision. His pupils are equally round and reactive to light. There is no relative afferent pupillary defect in either eye. Extraocular movements are full. The intraocular pressures are 14 and 17 in the right and left eye, respectively.


On slit lamp exam of his eyes, there are no eyelid or adnexal abnormalities. His conjunctiva and sclera are noninjected and both corneas are clear. The anterior chambers are deep without evidence of cell, flare, or blood. He has lightly pigmented, hazel irises. On careful inspection, there are no abnormal blood vessels present on either iris.



Step 2/3


Clinical Pearl


Iris neovascularization, or rubeosis iridis, is a sign of ocular ischemia and has a variety of etiologies, including diabetic retinopathy. It is most commonly seen at the border of the pupil. It is clinically significant because it may be an indicator of neovascularization of the anatomic angle of the eye. The drainage outflow for aqueous humor is found in the angle, and these vessels may contract to seal it off, resulting in a secondary angle-closure attack.



For dilation, one drop of tropicamide 1% and one drop of phenylephrine 2.5% are instilled into both eyes. The lenses both have cataract changes, including central posterior subcapsular cataracts.


Tags:
Jun 15, 2016 | Posted by in GENERAL & FAMILY MEDICINE | Comments Off on 17 A 57-Year-Old Male With Blurred Vision

Full access? Get Clinical Tree
Get Clinical Tree app for offline access