Unraveling the genetic complexities of combined retinal dystrophy and hearing impairment.

Usher syndrome, the most prevalent cause of combined hereditary vision and hearing impairment, is clinically and genetically heterogeneous. Moreover, several conditions with phenotypes overlapping Usher syndrome have been described. This makes the molecular diagnosis of hereditary deaf-blindness challenging. Here, we performed exome sequencing and analysis on 7 Mexican and 52 Iranian probands with combined retinal degeneration and hearing impairment (without intellectual disability). Clinical assessment involved ophthalmological examination and hearing loss questionnaire. Usher syndrome, most frequently due to biallelic variants in MYO7A (USH1B in 16 probands), USH2A (17 probands), and ADGRV1 (USH2C in 7 probands), was diagnosed in 44 of 59 (75%) unrelated probands. Almost half of the identified variants were novel. Nine of 59 (15%) probands displayed other genetic entities with dual sensory impairment, including Alström syndrome (3 patients), cone-rod dystrophy and hearing loss 1 (2 probands), and Heimler syndrome (1 patient). Unexpected findings included one proband each with Scheie syndrome, coenzyme Q10 deficiency, and pseudoxanthoma elasticum. In four probands, including three Usher cases, dual sensory impairment was either modified/aggravated or caused by variants in distinct genes associated with retinal degeneration and/or hearing loss. The overall diagnostic yield of whole exome analysis in our deaf-blind cohort was 92%. Two (3%) probands were partially solved and only 3 (5%) remained without any molecular diagnosis. In many cases, the molecular diagnosis is important to guide genetic counseling, to support prognostic outcomes and decisions with currently available and evolving treatment modalities.

Neutrophil Extracellular Traps: Current Perspectives in the Eye.

Neutrophil extracellular traps (NETs) have been the subject of research in the field of innate immunity since their first description more than a decade ago. Neutrophils are the first cells recruited at sites of inflammation, where they perform their specific functions, including the release of NETs, which consist of web-like structures composed of granule proteins bound to decondensed chromatin fibres. This process has aroused interest, as it contributes to understanding how pathogenic microorganisms are contained, but they are also associated with pathophysiological processes of a wide range of diseases. Currently, there are growing reports of new molecules involved in the formation and release of NETs. However, whether the release of NETs contributes to eye diseases remains unclear. For this reason, the overall aim of this review is to gather current data of recent research in the ophthalmology field, where there is still much to discover.

Endothelial cell density changes in diabetic and nondiabetic eyes undergoing phacoemulsification employing phaco-chop technique.

PURPOSE: To assess endothelial cell density (ECD) changes on diabetic and nondiabetic patients after phacoemulsification surgery employing the phaco-chop technique. METHODS: This is a prospective, experimental and comparative study. We included type-two diabetic (T2DM) patients and nondiabetic patients who underwent phacoemulsification performed by a single surgeon employing the horizontal phaco-chop technique. ECD and central corneal thickness (CCT), the coefficient of variation and percentage of polymegathism were measured and compared. Specular microscopy was used to evaluate the number of endothelial cells in patients during surgical pre-assessment and at the 1- and 3-month follow-up visits. RESULTS: A total of 42 eyes from 42 patients were included: 21 eyes in the T2DM group and 21 eyes in the nondiabetic group. No statistically significant differences were found between groups in terms of age and sex distribution (p = 0.296; p = 0.502, respectively). Mean postoperative (at 1 and 3-month follow-up) endothelial cell count of the T2DM group was not significantly lower than the nondiabetic group (p = 0.341 and p = 0.065, respectively). Postoperative CCT measurements demonstrated no significant variations between groups, showing a mean 557.8 ± 48.0 and 543.3 ± 41.0 µm, respectively (p = 0.472). Nonetheless, significant differences were evidenced for CoV values for both the pre-surgical and the postoperative follow-up visits between groups, as well as ECD values inside each group. CONCLUSIONS: The present study reveals significant differences between pre-surgical and postoperative mean ECD values; however, no statistically significant differences were found when comparing ECD at each follow-up visit between diabetic patients without evidence of high-risk proliferative diabetic retinopathy and nondiabetic patients undergoing phacoemulsification employing phaco-chop technique.