Quantitative assessment of anterior chamber parameters in pigmentary glaucoma using slit-lamp optical coherence tomography

PURPOSE. To quantitatively assess the parameters of anterior chamber and angle dimensions by slit-lamp optical coherence tomography (SL-OCT) in eyes with pigmentary glaucoma (PG). METHODS. A total of 18 eyes of 11 patients with PG and 18 eyes of 11 healthy volunteers were included in the study. Anterior chamber depth (ACD), anterior chamber volume (ACV), spur distance (internal horizontal anterior chamber diameter), central corneal thickness (CCT), angle opening distance at 500 pm from the scleral spur (AOD 500), and trabecular iris space area at 500 pm from the sclera! spur (TISA 500) parameters were detected by SL-OCT. The differences of anterior chamber parameters between patients with PG and the control group were analyzed by Mann-Whitney U test. RESULTS. Mean ACD and ACV were measured as 3.28 +/- 0.38 mm and 191.6 +/- 39.7 mm(3) respectively in the PG group. Mean AOD 500 and TISA 500 were 0.88 +/- 0.47 mm and 0.29 +/- 0.15 mm(2) at the nasal angle and 1.14 +/- 0.67 mm and 0.41 +/- 0.23 mm(2) at the temporal angle, respectively. Nasal and temporal angles were 49.83 +/- 11.1 degrees and 53.83 +/- 10.46 degrees. In eyes with PG, the midperipheral iris configuration was found to be considerably concave in 15 eyes (83.3%). Except CCT and spur distance, all anterior chamber dimension and angle parameters detected by SL-OCT were found to be significantly higher in the eyes with PG (Mann-Whitney U test, p<0.05). CONCLUSIONS. SL-OCT provided highly quantitative data on the parameters of anterior chamber and angle dimensions in PG. The evaluation of the anterior segment anatomy using SL-OCT revealed increased anterior chamber dimensions and posterior bowing of the iris consistent with the increase in angle parameters in patients with PG. (Eur J Ophthalmol 2010; 20: 702-07)