Ocular abnormalities in a large patient cohort with retinitis pigmentosa in Western China

Outcomes of vitreoretinal surgery in eyes with retinitis pigmentosa without retinal detachment

PURPOSE

Outcomes of retinal detachment (RD) have been discussed in detail in many reports of patients with retinitis pigmentosa (RP). This study tries to understand the outcomes of vitreoretinal (VR) surgery for indications other than RD in the eyes with RP.

METHODS

This is a retrospective study that includes clinical data from January 2013 to December 2021. Patients with RP who were treated with a VR surgical intervention were included in the study. The primary outcome of the study was to assess the changes in best-corrected visual acuity.

RESULTS

Forty-four eyes of 40 patients with RP were included in the study. Nearly half of the eyes (43%, 19/44) presented from 1 month to 1 year after the onset of diminished vision, with or without floaters. The mean ± standard deviation (SD) best-corrected visual acuity (BCVA) at presentation was 1.30 ± 0.79 logMAR (20/400 ± 20/125). The major surgical indications were vitreous opacities (43.2%, 19/44) and subluxated/dislocated cataractous lenses (25%, 11/44). The median follow-up duration was 8 months (interquartile range (IQR): 1.5-27). Approximately 77% (34/44) of the eyes had improvement in vision. The mean postoperative BCVA at the last follow-up was 0.95 ± 0.73 logMAR (p-value: 0.03).

CONCLUSIONS

Most eyes with RP recovered well after VR surgical interventions, with short-term improvements in visual acuity. It may be crucial to address the vitreous opacities and membranes as they hinder the residual central island of vision in RP. However, appropriate counselling is required regarding the progressive nature of retinal neuronal degeneration.

Bilateral angle closure glaucoma with retinitis pigmentosa in young patients: case series

BACKGROUND

To report the ocular characteristics and management of three cases of retinitis pigmentosa (RP) concurrent primary angle closure glaucoma (PACG).

CASE PRESENTATION

Three middle-aged patients presenting with diminished vision, high intraocular pressure (IOP), and typical fundus manifestations of RP were clinically evaluated. The individualized treatment was based on the ocular conditions of each case. A novel genetic alteration in ZNF408 was identified in one patient. Two patients with short-axial eyes received unilateral combined trabeculectomy, cataract surgery, and Irido-zonulo-hyaloid-vitrectomy. One of them had a subluxated lens, managed with a capsular tension ring implantation. Their contralateral eyes, respectively, underwent laser peripheral iridotomy (LPI) and transscleral cyclophotocoagulation. The third patient underwent bilaterally combined laser peripheral iridoplasty, LPI, and medication. Ultimately, all patients achieved the target IOP during a two-year follow-up.

CONCLUSION

Young patients with RP may have a risk of developing angle closure glaucoma, and conversely, patients with angle closure glaucoma at younger age should be aware of the presence of RP. Therefore, routine gonioscopy and IOP monitoring are required for RP patients, and detailed fundus examinations are warranted for young PACG patients.

Case report: A frameshift mutation in CLCN2-related leukoencephalopathy and retinopathy

Background: Leukoencephalopathy and visual impairment have been linked to loss-of-function mutations in the CLCN2 gene (MIM #600570). However, the ocular features caused by the CLCN2 mutations remain poorly understood and seldom reported. This study aims to present a novel mutation and characterize the ocular phenotype in a Chinese female diagnosed with CLCN2-related leukoencephalopathy (CC2L), also known as leukoencephalopathy with ataxia (LKPAT; MIM #615651). Case presentation: A 20-year-old Chinese female presented with bilateral blurred vision persisting for 2 years, which had worsened over the past 6 months. Ophthalmologic examination revealed bilateral post-capsular cataracts, macular retinal atrophy, and peripheral retinal pigmentation. Swept-source optical coherence tomography (SS-OCT) showed bilateral choroidal capillary atrophy, loss of the outer retinal layer, and a novel noteworthy sign of vacuole-like vitreoretinopathy. Cranial magnetic resonance imaging confirmed leukoencephalopathy. Genetic testing identified a novel homozygous pathogenic c.1382_1386del (p.P461Lfs*13) mutation in exon 13 of the CLCN2 gene. Conclusion: This case report expands the knowledge of CLCN2 mutations and their associated ocular manifestations in patients with CC2L. The identified ophthalmic features may serve as crucial indicators for early diagnosis in individuals with CC2L, especially in the absence of evident neurological symptoms.

Investigating the associations of macular edema in retinitis pigmentosa

Macular edema (ME), the accumulation of intraretinal fluid in the macula, is a common sight affecting sequelae of retinitis pigmentosa (RP). However, it is unclear why some patients develop ME, and others do not. This study aims to identify associations between clinical-genetic factors in RP with ME. Patients with clinically confirmed RP cases were identified from the inherited retinal disease database at a large tertiary referral academic center. Demographic and genetic testing findings were noted. Additionally, optical coherence tomography volume scans were graded using a validated grading system. One hundred and six patients (73.1%) were found to have ME in at least one eye (OD = 88, mean = 37.9%, OS = 98, mean = 31.7%). Structurally, the presence of epiretinal membrane (ERM) (p < 0.007) and vitreo-macular traction (VMT) (p < 0.003) were significantly associated with ME. Additionally, X-linked (p < 0.032) and autosomal dominant inheritance (p < 0.039) demonstrated a significant association with ME, with RP1 (p < 0.045) and EYS (p < 0.017) pathogenic variants also significantly associated with ME. This study, in a large cohort of RP patients, confirms previous retinal structural associations for ME in RP and identifies potential new genetic associations.

Bilateral astrocytic hamartoma with vasoproliferative tumour in retinitis pigmentosa

We report a rare case of a 32-year-old Indian male who presented to the retina outpatient department with a history of sudden worsening of vision in the left eye. There was a background history of poor vision and deficient night vision since childhood. At the first presentation, the best corrected visual acuity was 6/36 and 6/60 in the right and left eye, respectively. Ocular examination revealed waxy pale disc, bone spicule pigmentation, attenuated vessels and epiretinal membrane in the right eye in keeping with retinitis pigmentosa. An astrocytic harmatoma was also present in the right eye. Vitreous haemorrhage in the left eye precluded a view of the fundus. He subsequently had a left pars plana vitrectomy, and intravitreal bevacizumab on account of non-resolving vitreous haemorrhage and a vasoproliferative tumour and astrocytic hamartoma were noticed intraoperatively. He had a good immediate post-operative outcome post-left vitrectomy but subsequently developed left neovascular glaucoma 2 years after. Neovascular glaucoma may be a sequela of vasoproliferative tumour; hence, regular follow-up and monitoring are essential in these patients.

Association between retinitis pigmentosa and an increased risk of primary angle closure glaucoma: A population-based cohort study

Background

Retinitis pigmentosa (RP) is the most frequent retinal hereditary dystrophy and result in blindness if progresses. Several case reports have revealed the possible association between RP and primary angle-closure glaucoma (PACG). We conducted a population-based study to explore whether RP significantly increased the risk of PACG development.

Methods

Using the Taiwan National Health Insurance Research Database, we enrolled patients with RP into the RP group from 2001 to 2013 and included a comparison group of 1:4 age- and sex-matched individuals without RP. We performed a Cox regression analysis to estimate the crude and adjusted hazard ratios (HRs) of RP for PACG after adjustment for hypertension, diabetes, hyperlipidaemia, chronic kidney disease, and lens subluxation.

Results

We enrolled 6223 subjects with RP and 24892 subjects for comparison. The mean age of the cohort was 49.0 ± 18.1 years. The RP group had significantly higher percentages of diabetes mellitus, hypertension, and hyperlipidaemia. The cumulative incidence of PACG in patients with RP was 1.61%, which was significantly higher than that in the comparison group (0.81%, p < 0.0001). According to the univariate Cox regression analysis, the hazard of PACG development was significantly greater in the RP group, with an unadjusted HR of 2.09 (95% confidence interval [CI], 1.64–2.65). The increased risk persisted after adjusting for confounders (adjusted HR = 2.18; 95% CI, 1.76–2.72).

Conclusion

This nationwide population-based cohort study showed that people with RP are at a significantly greater risk of developing PACG than individuals without RP.

Patients with Retinitis Pigmentosa May Have a Higher Risk of Developing Open-Angle Glaucoma

Background

Retinitis pigmentosa (RP) is the most common retinal hereditary dystrophy, which can lead to blindness if it progresses. Similarly, open-angle glaucoma (OAG) is a genetic disorder. The similarities in genetic variants and pathophysiology between RP and OAG have been reported. We sought to explore whether patients with RP have a significantly higher risk of OAG development.

Methods

We enrolled patients with RP into the RP group through Taiwan's National Health Insurance Research Database from 2001 to 2013; we included a comparison group of 1 : 4 age- and gender-matched individuals without RP. We performed a Cox regression analysis to estimate the crude and adjusted hazard ratios (HRs) for OAG. We adjusted the following confounders in the Cox regression model: age, gender, diabetes mellitus, hypertension, and chronic kidney disease.

Results

We enrolled 6,223 subjects with RP and 24,892 subjects for comparison. The mean age of the cohort was 49.0 ± 18.1 years. The RP group had significantly higher percentages of diabetes mellitus, hypertension, and hyperlipidaemia. The cumulative incidence of OAG in patients with RP was 1.57%; this was significantly higher than that in the comparison group (0.58%, p < 0.0001). On univariate Cox regression analysis, the hazard of OAG development was significantly greater in the RP group than in the comparison group with an unadjusted HR of 2.86 (95% confidence interval, 2.21–3.70). The increased risk persisted after adjusting for confounders (adjusted HR = 2.86; 95% CI, 2.21–3.70).

Conclusions

This nationwide population-based cohort study showed that people with RP are at a significantly greater risk of developing OAG than individuals without it.

Frequency of cystoid macular edema and vitreomacular interface disorders in genetically solved syndromic and non-syndromic retinitis pigmentosa

PURPOSE

Retinitis pigmentosa (RP) corresponds to a group of inherited retinal disorders where progressive rod-cone degeneration is observed. Cystoid macular edema (CME) and vitreomacular interface disorders (VMID) are known to complicate the RP phenotype, challenging an age-old concept of retained central visual acuity. The reported prevalence of these changes varies greatly among different studies. We aim to describe the frequency of CME and VMID and identify predictors of these changes in a cohort of Caucasian patients with genetically solved syndromic (sRP) and non-syndromic RP (nsRP).

METHODS

Cross-sectional study of patients with genetically solved sRP or nsRP. Genetic testing was clinically oriented in all probands and coordinated by a medical geneticist. The presence/absence of CME and VMIDs such as epiretinal membrane (ERM), vitreomacular traction (VMT), lamellar hole (LH), macular hole (MH), and macular pseudohole (MPH), and the integrity of the neurosensory retina and retinal pigment epithelium were evaluated in individual macular SD-OCT b-scans. Mixed-effects regression analysis models were used to identify significant predictors of BCVA, CME, and VMID. Significance was considered at α < 0.05.

RESULTS

We included 250 eyes from 125 patients. Mean age was 44.9 ± 15.7 years and 55.2% were male. Eighty-eight patients had nsRP and 37 had sRP. Median BCVA was 0.5 (0.2-1.3) logMAR. CME was found in 17.1% of eyes, while ERM was found in 54.3% of eyes. The frequency of CME (p = 0.45) and ERM (p = 0.07) did not differ between sRP and nsRP patients, nor across different inheritance patterns. Mixed-effects univariate linear regression identified age (p = 0.04), cataract surgery (p < 0.01), and loss of integrity of outer retinal layers (p < 0.01) as significant predictors of lower visual acuity, while increased foveal thickness (p < 0.01) and the presence of CME (p = 0.04) were predictors of higher visual acuity. On mixed-effects multivariable analysis, only increased foveal thickness was significantly associated with better visual acuity (p < 0.01).

CONCLUSION

We found that the burden of ERM and CME in RP patients is high, highlighting the importance of screening for these potentially treatable conditions to improve the quality of life of RP patients.

Ocular Characteristics of Patients with Leber Congenital Amaurosis 6 Caused by Pathogenic RPGRIP1 Gene Variation in a Chinese Cohort

Purpose

To delineate the clinical and genetic characteristics of Chinese patients with RPGRIP1-associated Leber congenital amaurosis 6 (LCA6).

Methods

After screening 352 unrelated families with clinically diagnosed RP, five LCA6 patients with RPGRIP1 variations from unrelated Chinese families were identified. Full ophthalmology examinations, including decimal best-corrected visual acuity (BCVA), fundus photography, fundus autofluorescence imaging, spectral-domain optical coherence tomography (SD-OCT), full-field electroretinography (ffERG), multifocal electroretinography (mfERG), perimetry, and flash visual evoked potential (FVEP), were performed. Target next-generation sequencing (NGS) and Sanger sequencing were performed for the five patients to identify and to validate candidate disease-causing variants.

Results

Five patients were molecularly diagnosed as the LCA6 associated with RPGRIP1 variation, with typical clinical characteristics including congenital night blindness, nystagmus, and visual defect, at an early age. Interestingly, LCA6 exhibited extensive clinical heterogeneity and the changes in the morphology and function were not completely consistent in the five LCA6 patients. Case 1 showed extensive inferior-nasal retinal atrophy with a corresponding area of hypofluorescence in fundus autofluorescence, and the fundus photograph was nearly normal in cases 2 and 3. The ERG results displayed a moderately reduced rod-system response in cases 1 and 2 and a significant reduced rod-system response in case 3. Both case 4 and case 5 showed mottled pigmentation in fundi and an unrecordable rod and cone-system response in ERG. Moreover, we identified eight compound variants and one homozygous variant in the five patients with RPGRIP1.

Conclusions

This is the largest report focused on the clinical electrophysiological features of patients with associated LCA6 caused by the variation in the RPGRIP1 gene in the Chinese population with an enriched phenotypic and genotypic background of LCA6 to improve future gene therapies.

Comparative Study of a Modified Sub-Tenon's Capsule Injection of Triamcinolone Acetonide and the Intravenous Infusion of Umbilical Cord Mesenchymal Stem Cells in Retinitis Pigmentosa Combined With Macular Edema

Retinitis pigmentosa (RP) is a hereditary retinal degenerative disease leading to eventual blindness. When RP is combined with macular edema (ME), the visual impairment further worsens. We compared a modified sub-Tenon’s capsule injection of triamcinolone acetonide (TA) and the intravenous infusion of umbilical cord mesenchymal stem cells (UCMSCs) in the treatment of RP combined with ME (RP-ME) to assess their safety and efficacy in eliminating ME and restoring visual function. A phase I/II clinical trial enrolled 20 patients was conducted. All patients were followed up for 6 months. There were no severe adverse effects in both groups. In retinal morphological tests, the central macular thickness (CMT) in TA group significantly decreased at first week, first and second month after injection (p < 0.05). The CMT in UCMSCs group significantly decreased at first month after infusion. The rate of reduction of CMT in TA group was significantly greater than that in UCMSCs group at second month (p < 0.05). Reversely, the rate of reduction of CMT in UCMSCs group was significantly greater than that in TA group at sixth month (p < 0.05). In visual functional test, although there were no significant differences in visual acuity or visual fields within each group or between groups, but the amplitude of P2 wave of flash visual evoked potential (FVEP) showed significant increasing in TA group at second month in UCMSCs group at sixth month (p < 0.05). At 6th month, the rate of growth in the amplitude of P2 wave in USMCSs group was significantly greater than that in TA group (p < 0.05). This study suggests both modified sub-Tenon’s capsule injection of TA and intravenous infusion of UCMSCs are safe for RP-ME patients. TA injection is more effective at alleviating ME while improving visual function in a short term. UCMSC intravenous infusion shows slow but persistent action in alleviating ME, and can improve the visual function for a longer time. These approaches can be applied separately or jointly depending on the disease condition for patients to benefit maximumly.

Clinical Trial Registration:http://www.chictr.org.cn, identifier ChiCTR-ONC-16008839