Comparing anterior segment optical coherence tomography and ultrasound biomicroscopy with histopathology in measurement of corneal and bulbar conjunctival tumors depth

Abstract

PurposeCorneal and bulbar conjunctival tumors can be visualized and measured by Anterior Segment Optical Coherence Tomography (A‐OCT) and Ultrasound Biomicroscopy (UBM). We compared tumor depth measured by histopathology (HP) with measurements by UBM and A‐OCT to investigate whether the two techniques are as accurate as HP.Methods35 patients with 42 corneal or conjunctival bulbar tumors were imaged with A‐OCT and UBM. 11 of the tumors were excised and analyzed on histopathology. The correlation of the depth measurements on HP versus A‐OCT and UBM was statistically analyzed. When the tumor was not excised, depth measurements on A‐OCT versus UBM were compared.ResultsStatistical analysis showed that UBM and HP measurements of tumor depth are positively correlated, as are UBM and A‐OCT measurements. It was not possible to obtain statistically significant data for the correlation between HP and A‐OCT measurements because of the small study population. Image quality was overall better with A‐OCT than with UBM, but in 12 tumors, depth measurement on A‐OCT was impossible because of tumor shadowing (thick or highly pigmented tumor).ConclusionsUBM can measure tumor depth as accurately as HP. Tumor depth measurements on A‐OCT and UBM are positively correlated. A larger study is needed to investigate whether measurement of tumor depth with A‐OCT is as accurate as HP. Because of drawbacks of depth measurements on histopathology, we believe that A‐OCT and UBM could become the golden standard for measuring corneal and bulbar conjunctival tumor depth. We advise to use A‐OCT if the tumor is not too thick or too pigmented, and to use UBM in case of posterior tumor shadowing on OCT.