Van Herick Plus
Reviewed by Jonathan Chan

This a consecutive cross-sectional study of 95 phakic patients over the age of 40-years-old. By applying a short, vertical slit beam, the inferior angle at the scleral-limbal junction at 6 o’clock position was evaluated, photographed and assessed by a ratio of peripheral anterior chamber depth to the peripheral corneal thickness (PAC-PCT) and the iridocorneal angle (ICA) on imageJ software. The inferior angle at the same meridian was also recorded on anterior segment optical coherence tomography (ASOCT). All the subjects were divided into four groups, based on the ratio of PAC/PCT: one (<1/4), two (1/4-1/2), three (>1/2-1), four (>1). The clinically assessed angle by short vertical slit beam correlated well with ASOCT values, scleral spur angle and trabecular-iris angle (TIA) (p<0.0001). The mean difference between ICA and TIA on ASOCT was 0.797 degrees (95% limits of agreement between 5.767 to 7.361 degrees). For narrow angles graded on ASOCT (TIA<20 degrees), using a cut-off of peripheral PAC: PCT<1/4, the area under the curve was 0.918 with a sensitivity of 85.2% and a specificity of 88.2%. The authors concluded that this clinical technique correlated well with ASOCT and was reliable and accurate screening tool for identifying occludable angles.

‘Van Herick Plus’: a modified grading scheme for the assessment of peripheral anterior chamber depth and angle.
Sihota R, Kamble N, Sharma AK, et al.
BRITISH JOURNAL OF OPHTHALMOLOGY
2019;103:960-5.