Evaluation of the anterior chamber angle in Asian Indian eyes by ultrasound biomicroscopy and gonioscopy.
OBJECTIVE
To compare the ultrasound biomicroscopic measurement of the anterior chamber angle in Asian Indian eyes, with the angle width estimated by gonioscopy.


METHODS



METHODS
Patients with open and closed angles attending a glaucoma clinic were recruited for the study.


METHODS
Temporal quadrants of the angles of patients were categorized by gonioscopy as Grade 0 to Grade 4, using Shaffer's classification. These angles were quantified by ultrasound biomicroscopy (UBM) using the following biometric characteristics: Angle opening distance at 250 micro (AOD 250) and 500 micro (AOD 500) from the scleral spur and trabecular meshwork-ciliary process distance (TCPD). The angles were further segregated as "narrow angles" (Schaffer's Grade 2 or less) and "open angles" (Schaffer's Grade 3 and 4).


METHODS
The UBM measurements were computed in each case and analyzed in relation to the gonioscopic angle evaluation.


RESULTS
One hundred and sixty three eyes of 163 patients were analyzed. One hundred and six eyes had "narrow angles" and 57 eyes had "open angles" on gonioscopy. There was a significant difference among the mean UBM measurements of each angle grade estimated by gonioscopy (P < 0.001). The Pearson correlation coefficient between all UBM parameters and gonioscopy grades was significant at the 0.01 level. The mean AOD 250, AOD 500 and TCPD in narrow angles were 58+/-49 micro, 102+/-84 micro and 653+/-124 respectively, while it was 176+/-47 micro, 291+/-62 micro and 883+/-94 micro in eyes with open angles (P < 0.001) respectively.


CONCLUSIONS
The angle width estimated by gonioscopy correlated significantly with the angle dimensions measured by UBM. Gonioscopy, though a subjective test, is a reliable method for estimation of the angle width.
Kaushik
Sushmita
S
Department of Ophthalmology, Postgraduate Institute of Medical Education and Research, Chandigarh - 160 012, India. sushmita_kaushik@yahoo.com
Jain
Rajeev
R
Pandav
Surinder Singh
SS
Gupta
Amod
A
D000867:Anterior Chamber / Q000033:anatomy & histology* / Q000000981:diagnostic imaging*; D005260:Female; D005901:Glaucoma / Q000175:diagnosis* / Q000453:epidemiology; D006068:Gonioscopy / Q000379:methods*; D006801:Humans; D015994:Incidence; D007194:India / Q000453:epidemiology; D007498:Iris / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D008297:Male; D033401:Microscopy, Acoustic / Q000379:methods*; D008875:Middle Aged; D012590:Sclera / Q000033:anatomy & histology / Q000000981:diagnostic imaging; D014129:Trabecular Meshwork / Q000033:anatomy & histology / Q000000981:diagnostic imaging