Foveal pit morphological changes in asymptomatic carriers of the G11778A mutation with Leber's hereditary optic neuropathy

Prediction of postoperative visual acuity in patients with age-related cataracts using macular optical coherence tomography-based deep learning method

Background

To predict postoperative visual acuity (VA) in patients with age-related cataracts using macular optical coherence tomography-based deep learning method.

Methods

A total of 2,051 eyes from 2,051 patients with age-related cataracts were included. Preoperative optical coherence tomography (OCT) images and best-corrected visual acuity (BCVA) were collected. Five novel models (I, II, III, IV, and V) were proposed to predict postoperative BCVA. The dataset was randomly divided into a training (n = 1,231), validation (n = 410), and test set (n = 410). The performance of the models in predicting exact postoperative BCVA was evaluated using mean absolute error (MAE) and root mean square error (RMSE). The performance of the models in predicting whether postoperative BCVA was improved by at least two lines in the visual chart (0.2LogMAR) was evaluated using precision, sensitivity, accuracy, F1 and area under curve (AUC).

Results

Model V containing preoperative OCT images with horizontal and vertical B-scans, macular morphological feature indices, and preoperative BCVA had a better performance in predicting postoperative VA, with the lowest MAE (0.1250 and 0.1194LogMAR) and RMSE (0.2284 and 0.2362LogMAR), and the highest precision (90.7% and 91.7%), sensitivity (93.4% and 93.8%), accuracy (88% and 89%), F1 (92% and 92.7%) and AUCs (0.856 and 0.854) in the validation and test datasets, respectively.

Conclusion

The model had a good performance in predicting postoperative VA, when the input information contained preoperative OCT scans, macular morphological feature indices, and preoperative BCVA. The preoperative BCVA and macular OCT indices were of great significance in predicting postoperative VA in patients with age-related cataracts.

The Relative Preservation of the Central Retinal Layers in Leber Hereditary Optic Neuropathy

(1) Background: The purpose of this study was to evaluate the thickness of retinal layers in Leber hereditary optic neuropathy (LHON) in the atrophic stage compared with presumably inherited bilateral optic neuropathy of unknown cause with the aim of seeing if any LHON-specific patterns exist. (2) Methods: 14 patients (24 eyes) with genetically confirmed LHON (LHON group) were compared with 13 patients (23 eyes) with negative genetic testing results (mtDNA + WES) and without identified etiology of bilateral optic atrophy (nonLHON group). Segmentation analysis of retinal layers in the macula and peripapillary RNFL (pRNFL) measurements was performed using Heidelberg Engineering Spectralis SD-OCT. (3) Results: In the LHON group, the thickness of ganglion cell complex (GCC) (retinal nerve fiber layer (RNFL)—ganglion cell layer (GCL)—inner plexiform layer (IPL)) in the central ETDRS (Early Treatment Diabetic Retinopathy Study) circle was significantly higher than in the nonLHON group (p < 0.001). In all other ETDRS fields, GCC was thinner in the LHON group. The peripapillary RNFL (pRNFL) was significantly thinner in the LHON group in the temporal superior region (p = 0.001). Longitudinal analysis of our cohort during the follow-up time showed a tendency of thickening of the RNFL, GCL, and IPL in the LHON group in the central circle, as well as a small recovery of the pRNFL in the temporal region, which corresponds to the observed central macular thickening. (4) Conclusions: In LHON, the retinal ganglion cell complex thickness (RNFL-GCL-IPL) appears to be relatively preserved in the central ETDRS circle compared to nonLHON optic neuropathies in the chronic phase. Our findings may represent novel biomarkers as well as a structural basis for possible recovery in some patients with LHON.

Photoreceptor Manifestations of Primary Mitochondrial Optic Nerve Disorders

Purpose

To compare the manifestations of photoreceptors (PRs) in three hereditary optic neuropathies affected by primary mitochondrial dysfunction and discuss whether the retinal ganglion cells (RGCs) or the PRs are preferentially affected.

Methods

A retrospective analysis of patients with genetically confirmed diagnoses of optic neuropathies associated with mitochondrial dysfunction was performed. This cohort included Leber's hereditary optic neuropathy (LHON), autosomal dominant optic atrophy type 1 (OPA1), and optic atrophy type 13 (OPA13). Patient chart evaluations included clinical characteristics, best-corrected visual acuity (BCVA), fundus photography, spectral-domain optical coherence tomography (SD-OCT), electroretinogram (ERG), and visual evoked potential data.

Results

This analysis included seven patients with LHON, six with OPA1, and one with OPA13 from a tertiary medical center. Thirteen of the 14 individuals were male. The average BCVA at diagnosis was 20/285 and 20/500 in the right and left eyes, respectively. Five of the seven patients with LHON, and three of the six patients with OPA1 also showed a mild amplitude reduction or delayed latency on light-adapted ERG and 30-Hz flicker responses; however, SD-OCT imaging did not show correlated PR abnormalities. Notably, a 7-year follow-up of a patient with OPA13 revealed degeneration of RGCs prior to the degeneration of PRs. Follow-up data also demonstrated continuous loss of cone outer segment tips on SD-OCT imaging.

Conclusions

RGCs are, in general, affected by mitochondrial dysfunction, whereas variable PR dysfunction exists in patients with LHON and OPA1, especially with respect to the cone responses. Involvement of PRs is particularly evident in OPA13 after RGC degenerations.

Mitochondrial Syndromes Revisited

In the last ten years, the knowledge of the genetic basis of mitochondrial diseases has significantly advanced. However, the vast phenotypic variability linked to mitochondrial disorders and the peculiar characteristics of their genetics make mitochondrial disorders a complex group of disorders. Although specific genetic alterations have been associated with some syndromic presentations, the genotype–phenotype relationship in mitochondrial disorders is complex (a single mutation can cause several clinical syndromes, while different genetic alterations can cause similar phenotypes). This review will revisit the most common syndromic pictures of mitochondrial disorders, from a clinical rather than a molecular perspective. We believe that the new phenotype definitions implemented by recent large multicenter studies, and revised here, may contribute to a more homogeneous patient categorization, which will be useful in future studies on natural history and clinical trials.