It was a normal clinic day, on a week day to be precise; I was expecting patients that morning, as was the usual norm in a medium scale Optometric practice. This man walked in that I should help him work on his glasses( I also fit and mount lenses for my patients; not forgetting other optical works like frames adjustments, repairs etc to increase eye care services and hence reduce all forms of health care duplicity as encouraged by the health care terrain of our country!) I put up discussion with him and in no long time he opened up to me about his eye condition that has been on for 3 years now.
The man, 46 years, has a progressive bilateral distant blur that increases with peripheral gaze. He has associated near blur, feels disoriented sometimes which he attributed to the persistent "eye problem"! His Optometrist in Lagos gave him glasses for sight and for reading, gutt: Voltaren i tds x1/12 and eye antioxidants that he has been using for 3 years on! The problem is that the eyes does not seem to be improving and this patient is preparing to go to "Ijebu" to go and find out from a spiritist who was responsible for his eye condition.
The present glass was already 3 years worn habitually by the patient so I asked him to run some tests to enable me renew his glass prescription.
His visual acuity @ 6 meters:
RE: 6/9
LE:6/9-3
&
Visual acuity @40 cm
BE: N8
He used his habitual prescription to read the visual acuity chart (+0.75 DS add 2.25)
Refraction
RE: +1.00 DS 6/9
LE: +1.25 DS 6/12 (It turned out that the retinoscope light probably dazzled his eyes!; after 10 minutes, he read 6/9-2 with the same power ipsilaterally.)
At near +2.50 DS was added on his distant retinoscope finding to give him N6 OU! ( Do you understand anything unusual here?)
No meaningful improvement with the new retinoscope finding, objectively and subjectively! Again, this man's age and the near add shows an underlying condition that seems to be suppressing his near acuity! Or else why will a 46-year old man use a combined +3.50 DS readers and still cannot use it to see N5! Hmmm...
Funduscopy was carried out and the bilateral temporal- peripheral retina of each eye showed haziness and choroidal vascular degenerations, more prominent on the left eye than on the right eye!
His cup-to-disc ratio is OD 0.3, OS 0.3 an associated pallor not consistent with glaucoma nor optic nerve atrophy was seen. The diagnosis was blurring around its edges, the symptoms greying out such that subtle and sublime dynamic skills was required to arrive at a tentative diagnosis with sketchy information available. So what could be the cause? Was I getting confused? Should I leave him with his habitual management regimen or do I explore other options?
Plan: IOP (intra ocular pressure) measurement with Handheld Goldmann Applanation Tonometer, central visual field examination and dilated funduscopy of both eyes!
His intra ocular pressure on OD=14.5 mmHg, OS=14 mmHg @ 4pm! Central visual field result showed a bi-temporal scotoma, prominent on his OS than OD with macular sparing of both eyes, dilated funduscopy of both eyes showed choroidal vascular degenerations probably extending to the Ora serrata area (Do not judge me cos there was no indirect Ophthalmoscope to view the Ora serrata proper!)
Still not very convinced, I did some digging into the symptoms of bi-temporal hemianopia and came up with a subtle, but clinically relevant symptom- mental confusion is associated with many cases of Bi-temporal hemianopia! I called his primary eye care specialist in Lagos to inform him of the development and asked the man to run an MRI scan to find out the underlying cause of his condition or to rule out compression of the chiasma by an obstructing tumor and to take the results to his primary eye care physician!
Two weeks later, he returned to thank me generously and even made me feel like a chief priest of Ogun!
He has since been flown to India for removal of the tumor and I feel so satisfied to have been of help!
Note: "Bitemporal Hemianopia is a type of partial blindness where vision is missing in the outer half of both the right and left visual fields. Usually associated with the lesions of the optic chiasms, bitemporal hemianopia causes patients to experience difficulty seeing in both eyes." (www.hemianopiasociety.com/what-is-bitemporal-hemianopia)
Bitemporal hemianopia can be caused by the following:
a) Pituitary adenomas,
b) Craniopharyngiomas, or
c) neoplastic menangiomas
d) aneurysm of the anterior communicating artery which arise superior to the chiasm.
(en.wikipedia.org/wiki/Bitemporal_hemianopsia)
Again, Bitemporal hemianopia causes a damage to the crossing fibers of the optic chiasm which interrupts fibers from the nasal hemi retina of both eyes. The nasal hemi retina relays information that originated from the outer visual field. (http://www.csus.edu/indiv/m/mckeoughd/learningmodules/CtrVisualPathModule.pps)
Hope we started on a positive note? More to come on On same topic soonest! Thank God it is weekend!
Dr Victor Ezebuiroh
We are not doing this for financial rewards, hence no financial attachment! Feel free to share and comment!
