Use of Intraoperative Fourier-Domain Anterior Segment Optical Coherence Tomography During Descemet Stripping Endothelial Keratoplasty

Purpose To determine the prevalence of trabecular-iris contact (TIC) and quantify this contact in healthy Caucasian individuals using Fourier-domain optical coherence tomography (FD-OCT). Methods For this cross-sectional study, 2,012 eyes of 1,006 healthy subjects were recruited among individuals undergoing a routine ophthalmologic checkup. In each participant, age, sex, intraocular pressure, and spherical refractive error were first recorded along with anterior chamber depth and volume, central corneal thickness measured with the Pentacam, and axial length with the IOLMaster. Anterior chamber angle variables and the presence of TIC in the horizontal quadrants were determined by anterior segment FD-OCT (RTVue 100®). When TIC was observed, TIC length (TICL) and its percentage in relation to the length of the trabecular meshwork (TICL percentage) were also measured. Results Trabecular-iris contact in the horizontal quadrants was observed in 34 eyes of 25 patients, representing 1.6% of the total number of eyes examined. In this subgroup of individuals, mean age was 55.8 years, 84% were women, and spherical refractive error ranged from -0.25 to 8.25 D. Eyes with TIC showed an angle width of less than 23.2 degrees and axial length shorter than 23.7 mm. Mean TICL was 239 ± 79 μm (103-495 μm) and mean TICL percentage was 46.9% ± 13.9% (17.2%-76.3%). Conclusions The prevalence of TIC was low in this population. Fourier-domain optical coherence tomography emerged as useful to assess its prevalence and quantify the extent of TIC.

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‘Acute-angled bevel’ sign to assess donor lenticule orientation in ultra-thin descemet stripping automated endothelial keratoplasty

BMJ Case Reports ◽

10.1136/bcr-2018-227927 ◽

2019 ◽

Vol 12 (2) ◽

pp. e227927 ◽

Cited By ~ 2

Author(s):

Jeewan S Titiyal ◽

Manpreet Kaur ◽

Farin Shaikh ◽

Aafreen Bari

Keyword(s):

Optical Coherence Tomography ◽

Anterior Segment ◽

Acute Angle ◽

Optical Coherence ◽

Endothelial Keratoplasty ◽

Anterior Segment Oct ◽

Intraoperative Optical Coherence Tomography ◽

Congenital Hereditary Endothelial Dystrophy ◽

Graft Insertion

A 6.5-year-old boy with congenital hereditary endothelial dystrophy underwent clear corneal ultra-thin descemet stripping automated endothelial keratoplasty (DSAEK). After graft insertion, it was difficult to assess graft orientation due to hazy cornea. Intraoperative optical coherence tomography (iOCT) showed a well-attached graft and the bevelled edge of donor lenticule made an acute angle with the overlying stroma. Postoperative anterior segment OCT confirmed the presence of acute-angled bevel sign. A wetlab experiment was performed with experimental corneoscleral tissues to confirm the findings. Donor lenticule was injected in the artificial chamber with stromal-side up as well as stromal side-down. ‘Acute-angled bevel sign’ was observed on iOCT in the experimental cases with stromal-side up. In inverse graft, the acute-angled bevel was not observed, instead the configuration was obtuse angled. Identifying the ‘acute-angled bevel sign’ on iOCT confirms correct graft orientation after unfolding and is extremely useful for hazy corneas and ultrathin DSAEK lenticules.

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