This article is more than 5 years old. Information may no longer be current.
Light meter may help diagnose, monitor endophthalmitis
Click Here to Manage Email Alerts
A device that helps to assess the transparency of the vitreous appears to be useful for diagnosing and monitoring the progression of endophthalmitis, a study suggests.
Yogesh Gupta, MD, and colleagues at Aligarh Muslim University in India designed and tested the device, which they dubbed a digital mediameter, for gauging the severity and progression of endophthalmitis after cataract surgery. They described their study in the December issue of the Asian Journal of Ophthalmology.
The device consists of a standard Heine transilluminator and a Mastech MS6610 Luxmeter. The transilluminator shines light through the sclera at a fixed point 8 mm from the temporal limbus. The light meter is attached to the cornea or sclera and is encased in a black tube to prevent exterior light from interfering with readings.
"The basic principle ... is that any light that reaches the vitreous cavity is reflected from the retina and choroid. Thus, the intensity of light emanating from the pupil and the sclera during mediametry is directly proportional to the transparency of the ocular media," the study authors said.
The device may offer "a more reliable alternative to subjective assessment by conventional transillumination," the authors said.
Dr. Gupta and colleagues compared mediametry readings in 11 eyes with confirmed endophthalmitis with those from 20 healthy control eyes. All eyes had previously undergone extracapsular cataract extraction and IOL implantation.
Control eyes had a mean log value of 2.14 for transcorneal mediametry and 1.6 for transscleral mediametry. Eyes with endophthalmitis had significantly lower readings, averaging 1.72 for transcorneal mediametry and 1.42 for transscleral mediametry (P < .001), according to the study authors.
The researchers found significant positive correlations between both transscleral and transcorneal mediametry values and both increasing ocular clarity and visual acuity.
"It is clear from this that when the vitreous cavity contains exudates and cells, transmission of white light is hampered. The transmission of light through the ocular media increases as the visual acuity and the media clarity improves," the study authors said.
"The digital mediameter described here is reliable, easy to use, cost effective and portable, and may provide information on the status of endophthalmitis comparable to, or even superior to, many state-of-the-art instruments," they said.