Purchase this article with an account.
Deepa Kasaragod, Shuichi Makita, Yuta Ueno, Sujin Hoshi, Shinichi Fukuda, Tetsuro Oshika, Yoshiaki Yasuno; Evaluation of filtration bleb by multi-contrast anterior-segment optical coherence tomography. Invest. Ophthalmol. Vis. Sci. 2016;57(12):5129.
Download citation file:
© ARVO (1962-2015); The Authors (2016-present)
Blebs are evaluated by multi-contrast Jones matrix optical coherence tomography (JM-OCT). Scattering OCT, birefringence tomography and OCT angiography (OCT-A) are simultaneously obtained by JM-OCT. The features in the tomographies are discussed in a descriptive manner.
Six eyes of 4 patients who had undergone glaucoma filtration surgery were imaged by a custom-built multi-contrast JM-OCT. Multi-contrast volumetric images listed above were obtained on 6 mm x 6 mm area using a protocol of 256 A-lines × 256 B-scans × 2 repeats at the same location. Intraocular pressure (IOP) was measured using a Goldmann’s applanation tonometer. Multi-contrast cross-sectional images are created as follows: The birefringence tomography is displayed in a pseudo color image in which the color and brightness represent the birefringence and scattering, respectively. Cross-sectional OCT-A signal (red) is overlaid on scattering OCT (green).
Figure 1 shows the case of a 65-year-old male patient imaged 6-day after trabeculectomy (IOP = 6 mmHg). In the birefringence images (a, c, e), high birefringence of sclera is visible beneath the fluid pool (white arrow heads). In OCT-A images (b, d, f), nearly no or only a very small vessels exist above the fluid pool in the ischemic region (b, white arrow), while large vessels are visible beneath the fluid pool (red arrow). In non-ischemic region, large vessels are visible in the superior tissue to the fluid pool (f, yellow arrow heads).In 5 out of 6 cases, superior tissues do not show high birefringence in both ischemic and non-ischemic regions. In 3 of 6 cases, ischemic region is appeared with large flow regions in deep layers or below fluid pool. 2 cases show no presence of larger vessels in ischemic region at any depth. In 3 of 6 cases, large vessels are seen above fluid pool at non-ischemic region.
Late bleb leakage has often been associated with the presence of large avascular bleb. Hence OCT-A would be useful for its prediction. The birefringence tomography specifically visualizes the collagenous tissue. So, it can be utilized for the detection of subconjunctival fibrosis and scarring. In addition, scattering OCT is known to be useful for morphological bleb analysis. JM-OCT, which provides all these images simultaneously, could contribute to further optimize the filtration surgery.
This is an abstract that was submitted for the 2016 ARVO Annual Meeting, held in Seattle, Wash., May 1-5, 2016.
This PDF is available to Subscribers Only