Optical Coherence Tomography in Knobloch Syndrome.

BACKGROUND AND OBJECTIVE: Knobloch syndrome is a genetic disorder defined by occipital defect, high myopia, and vitreoretinal degeneration. The authors studied retinal changes in patients with Knobloch syndrome using optical coherence tomography (OCT). PATIENTS AND METHODS: The authors report patients with Knobloch syndrome who received OCT testing during their care from 2011 to 2016. Diagnosis was based on high myopia, characteristic fundus, and occipital scalp or skull abnormalities with/without featureless irides and/or ectopia lentis. When available, diagnosis was confirmed by the detection of COL18A1 mutations. RESULTS: The authors studied eight eyes from five patients. Two eyes were excluded due to chronic retinal detachment. OCT findings included epiretinal membrane, peripapillary vitreoretinal traction with retinoschisis, absent or rudimentary foveal pits, mean macular thickness of 113.4 µm, poor lamination, retinal pigment epithelium (RPE) atrophy, photoreceptor depletion, and mean choroidal thickness of 168.5 µm with enlarged choroidal vessels. CONCLUSION: OCT findings in Knobloch syndrome include abnormal vitreoretinal traction, poor foveal differentiation, poor retinal lamination, retinal thinning, RPE attenuation, myopic choroidal thinning, and pachychoroid. [Ophthalmic Surg Lasers Imaging Retina. 2019;50:e203-e210.].

Imaging modalities for localization of an iStent(®).

The iStent (Glaukos Corporation, Laguna Hills, CA) is a 1-mm, titanium trabecular bypass stent implanted across the inner wall of Schlemm's canal under direct gonioscopy. This study was designed to determine the best modality to identify iStent placement when gonioscopic visualization is not possible. In this in vitro study on a human cadaver eye, ultrasound biomicroscopy (UBM), anterior segment optical coherence tomography (AS-OCT), and B-scan ultrasonography were done to visualize and precisely locate two intentionally misplaced iStents. UBM could localize both intentionally misplaced stents, whereas AS-OCT could not visualize the iStent that was lodged in the sulcus. B-scan ultrasonography was unable to detect either of the stents. UBM may be a useful imaging modality to identify iStent in the anterior or posterior chamber, whereas AS-OCT is limited to detection of stents in the anterior chamber alone. B-scan ultrasonography is unable to identify iStent in either the anterior or posterior chamber.

High prevalence of plateau iris configuration in family members of patients with plateau iris syndrome.

PURPOSE: The purpose of the study was to ascertain the prevalence of plateau iris syndrome in the first-degree relatives of those patients affected with plateau iris syndrome. METHODS: All patients seen with plateau iris syndrome over a 5-year period were identified. These patients were approached for participation and first-degree family members above 18 years of age were screened. All people identified with plateau iris configuration underwent ultrasound biomicroscopy to document and confirm the angle configuration and subsequent gonioscopy after laser iridotomies. RESULTS: Sixteen patients were identified; 3 refused to participate, 2 were unable to be contacted, and 1 withdrew after initially consenting to participate. In this case, the patient agreed to participate, but all her living first-degree family members refused to be screened. Among the 10 patients whose living first-degree relatives were screened, we found 5 families with at least 1 additional first-degree family member having plateau iris syndrome. CONCLUSIONS: Some families have more than 1 member with plateau iris syndrome. The pattern of inheritance resembles an autosomal dominant pattern with incomplete penetrance.