Content area
Full Text
SUMMARY
Evaluation of macular function in cataract patients using blue field entoptoscopy (BFE) has been reported as useful in all cases by some authors; another found it useful only in patients with moderate visual acuity loss due to cataract.
This paper reports findings in 101 cataractous eyes evaluated consecutively with BFE. A strong correlation was found between cataract type and percentage of false negatives, but the correlation between the preoperative acuity level and percentage of false negatives was poor. BFE was also poor in detecting moderate macular dysfunction (20/60 - 20/80).
Four cases with profound visual acuity loss due to macular holes had normal perception of BFE.
Several methods of evaluating macular function in preoperative cataract patients have been described but all become progressively more unreliable as the cataract becomes more opaque.1 Sinclair et al.2 have used the blue field entoptic phenomenon (BFE) to evaluate macular function in cataract patients and found it highly reliable in predicting both good and poor macular function. This was in spite of over half of their patients having finger-counting or worse preoperative acuity. Skalka,1 however, using a commercially available blue field entoptoscope developed from the Sinclair et al. prototype found BFE to be reliable only in patients with less dense cataracts (20/400 or better acuity). He agreed that false positives (appreciated the BFE phenomenon but had poor postoperative acuity) were rare. Combining the two series the false positive rate was less than 1.5%.
This paper reports additional experience with the commercially available 500-watt tungsten lamp entoptoscope (MIRA BFE 100) in evaluating macular function in preoperative cataract patients.
MATERIALS AND METHODS
One hundred one consecutive patients that were already scheduled for cataract surgery were administered the BFE test by a trained technician using the MIRA BFE 100 blue field entoptoscope. Using the criteria of Sinclair et al.2 the results were recorded as positive (perceived without leading questions many (at least 1 5) corpuscles moving in the entire field) or negative (perceived no or only a few moving corpuscles). If a negative result was obtained with the low setting, the medium and then the high setting were employed. All patients were initially tested with an undilated pupil but if a negative response was obtained the test was repeated after...