Scleral indentation optimizes visualization of anterior chamber angle during goniosynechialysis.
OBJECTIVE
To propose a new surgical technique for optimized visualization of the chamber angle using scleral indentation under an operating microscope in goniosynechialysis (GSL).


METHODS
Six volunteers with normal chamber angle and five patients with synechial angle closure glaucoma were examined. Scleral indentation 2 mm posterior to the limbus was performed during observation of chamber angle. Width of trabecular meshwork in images was recorded through a CCD camera mounted on an operating microscope. Trabecular-iris angle and trabecular-corneal angle obtained by ultrasound biomicroscopy were used for the parameters for the angle configuration. GSL with scleral indentation was performed in the patients.


RESULTS
According to the visibility of the chamber angle, width of trabecular meshwork in images significantly increased from 0.34 +/- 0.08 mm equivalent (mean +/- SD) to 0.67 +/- 0.14 mm equivalent (P = 0.0001) with scleral indentation. According to the angle configurations, trabecular-iris angle significantly increased from 39.6 +/- 3.8 degrees to 47.5 +/- 6.6 degrees (P = 0.0016), and trabecular-corneal angle significantly decreased from 169.8 +/- 5.5 degrees to 158.7 +/- 5.4 degrees (P < 0.0001). All patients were successfully treated with GSL using scleral indentation.


CONCLUSIONS
Scleral indentation provided the surgeon an optimized visualization of the anterior chamber angle. Deepening of the chamber angle and steeping in trabecular-corneal curvature probably induced the plane of the trabecular meshwork less oblique to the surgeon's visual axis. This enhanced visualization promises the accuracy and safety of GSL.
Department of Ophthalmology, Faculty of Medicine, Shimane University, Izumo, Japan. takanash@med.shimane-u.ac.jp
Taiji
T
Takanashi
Hisashi
H
Masuda
Masaki
M
Tanito
Shin
S
Nonoyama
Tohru
T
Katsube
Akihiro
A
Ohira
D000368:Aged; D000369:Aged, 80 and over; D000867:Anterior Chamber / Q000000981:diagnostic imaging / Q000473:pathology*; D005260:Female; D015812:Glaucoma, Angle-Closure / Q000601:surgery*; D006068:Gonioscopy / Q000379:methods*; D006801:Humans; D007498:Iris / Q000000981:diagnostic imaging / Q000473:pathology; D008297:Male; D033401:Microscopy, Acoustic; D008875:Middle Aged; D013508:Ophthalmologic Surgical Procedures; D012590:Sclera; D014129:Trabecular Meshwork / Q000000981:diagnostic imaging / Q000473:pathology*