Gyrate atrophy with bilateral full thickness macular hole

[Gyrate atrophy of the choroid and retina with ornithinemia and foveoschisis (clinical observation)]

Gyrate chorioretinal atrophy (GCA) is a rare hereditary disease with certain complications; one extremely rare complication of GCA is foveoschisis. For the first time in Russian ophthalmology, a 10-year-old female child has been described to have genetically verified GCA associated with the OAT gene in combination with ornithinemia and foveoschisis. The diagnosis was made on the basis of fundus examination, perimetry data, autofluorescence, optical coherence tomography, fluorescence angiography, electroretinography, mass spectrometry with confirmation by molecular genetic research. The presented clinical case illustrates the need for an interdisciplinary approach to the diagnosis of GCA with diagnostic algorithm involving various examination methods and doctors of different specialties.

A review of treatment modalities in gyrate atrophy of the choroid and retina (GACR)

Gyrate atrophy of the choroid and retina (GACR) is a rare inborn error of amino acid metabolism caused by bi-allelic variations in OAT. GACR is characterised by vision decline in early life eventually leading to complete blindness, and high plasma ornithine levels. There is no curative treatment for GACR, although several therapeutic modalities aim to slow progression of the disease by targeting different steps within the ornithine pathway. No international treatment protocol is available. We systematically collected all international literature on therapeutic interventions in GACR to provide an overview of published treatment effects.

METHODS

Following the PRISMA guidelines, we conducted a systematic review of the English literature until December 22nd 2020. PubMed and Embase databases were searched for studies related to therapeutic interventions in patients with GACR.

RESULTS

A total of 33 studies (n = 107 patients) met the inclusion criteria. Most studies were designed as case reports (n = 27) or case series (n = 4). No randomised controlled trials or large cohort studies were found. Treatments applied were protein-restricted diets, pyridoxine supplementation, creatine or creatine precursor supplementation, l-lysine supplementation, and proline supplementation. Protein-restricted diets lowered ornithine levels ranging from 16.0-91.2%. Pyridoxine responsiveness was reported in 30% of included mutations. Lysine supplementation decreased ornithine levels with 21-34%. Quality assessment showed low to moderate quality of the articles.

CONCLUSIONS

Based primarily on case reports ornithine levels can be reduced by using a protein restricted diet, pyridoxine supplementation (variation-dependent) and/or lysine supplementation. The lack of pre-defined clinical outcome measures and structural follow-up in all included studies impeded conclusions on clinical effectiveness. Future research should be aimed at 1) Unravelling the OAT biochemical pathway to identify other possible pathologic metabolites besides ornithine, 2) Pre-defining GACR specific clinical outcome measures, and 3) Establishing an international historical cohort.

ATYPICAL MACULAR HOLES

PURPOSE

To study the etiology, clinical features, management options, and visual prognosis in various types of atypical macular holes (MHs).

METHODS

A review of the literature was performed, which focused on the etiopathogenesis of atypical or secondary MHs, their differentiating clinical features, management strategies, and varied clinical outcomes. Idiopathic or age-related, myopic, and traumatic MHs were excluded.

RESULTS

Atypical or secondary MHs arise out of concurrent ocular pathologies (dystrophy, degeneration, or infections) and laser/surgery. The contributing factors may be similar to those responsible for idiopathic or typical MHs, i.e., tangential or anteroposterior vitreofoveal traction or cystoid degeneration. The management is either observation or treatment of the underlying cause. The prognosis depends on the background pathology, duration of disease, and baseline visual acuity governed by the size of MH and morphologic health of underlying RPE and photoreceptors. The closer the morphology of atypical MH is to that of an idiopathic MH, the better the surgical outcome is.

CONCLUSION

With the advancements in retinal imaging, atypical MHs are now more frequently recognized. With increasing understanding of the underlying disease processes, and improvement in investigations and surgical treatment, management of atypical MHs may improve in the future.

Carbonic Anhydrase Inhibitor with Topical NSAID Therapy to Manage Cystoid Macular Edema in a Case of Gyrate Atrophy

Purpose

Gyrate atrophy of the choroid and retina (GACR) is a rare chorioretinal dystrophy characterized by a deficiency of the enzyme ornithine aminotransferase, inherited in an autosomal recessive pattern.

Case Report

We report a case of a 17-year-old girl with GACR, for whom the level of serum ornithine had been reduced by an arginine-restricted diet. The patient was responsive to an association of topical nonsteroidal anti-inflammatory drugs (NSAIDs) and a carbonic anhydrase inhibitor (CAI) to reduce cystoid macular edema (CME).

Conclusions

The efficacy of topical NSAIDs and systemic CAI association indicates that the imbalance in the distribution of retinal pigment epithelium membrane-bound carbonic anhydrase could play a major role in CME pathogenesis in GACR. To our knowledge, this is the first case of therapy with CAI treatment for GACR-related CME.

Arginine-Restricted Therapy Resistant Bilateral Macular Edema Associated with Gyrate Atrophy

Introduction. Gyrate atrophy is a rare genetical metabolic disorder affecting vision. Here, we report a 9-year-old boy with gyrate atrophy associated with bilateral macular edema at the time of diagnosis and the effect of long term metabolic control on macular edema. Case Presentation. A 9-year-old boy presented with a complaint of low visual acuity (best corrected visual acuity: 20/80 in both eyes, refractive error: −12.00 D). Dilated fundus examination revealed multiple bilateral, sharply defined, and scalloped chorioretinal atrophy areas in the midperipheral and peripheral zone. Spectral-domain optical coherence tomography revealed bilateral cystoid macular edema in both eyes. Serum ornithine level was high (622 μmol/L). An arginine-restricted diet reduced serum ornithine level (55 μmol/L). However, visual findings including macular edema remained unchanged in 2 years of follow-up. Conclusion. Arginine-restricted diet did not improve macular edema in our patient with gyrate atrophy. A more comprehensive understanding of the underlying factors for macular edema will lead to the development of effective therapies.

Bilateral full thickness macular holes in association with serpiginous choroiditis

PURPOSE

To report serpiginous choroiditis associated with full thickness macular holes (FTMH).

DESIGN

Interventional case report.

METHODS

A 58-year-old female with bilateral serpiginous choroiditis developed right-sided blurred vision and metamorphopsia. Ocular assessment, FFA, OCT, and right macular hole surgery were performed.

RESULTS

Preoperative visual acuity was 6/36 right, 6/9 left. Fundus assessment found bilateral geographic chorioretinal scarring, epiretinal membranes, right FTMH, and mild vitritis. OCT revealed bilateral FTMHs. Pars plana vitrectomy, membrane peel, and gas tamponade resulted in right macular hole closure, visual acuity improvement (6/18) and resolution of metamorphopsia.

CONCLUSIONS

Macular hole may be another posterior segment complication of serpiginous choroiditis.