Multi-omics approach dissects cis-regulatory mechanisms underlying North Carolina macular dystrophy, a retinal enhanceropathy.

North Carolina macular dystrophy (NCMD) is a rare autosomal-dominant disease affecting macular development. The disease is caused by non-coding single-nucleotide variants (SNVs) in two hotspot regions near PRDM13 and by duplications in two distinct chromosomal loci, overlapping DNase I hypersensitive sites near either PRDM13 or IRX1. To unravel the mechanisms by which these variants cause disease, we first established a genome-wide multi-omics retinal database, RegRet. Integration of UMI-4C profiles we generated on adult human retina then allowed fine-mapping of the interactions of the PRDM13 and IRX1 promoters and the identification of eighteen candidate cis-regulatory elements (cCREs), the activity of which was investigated by luciferase and Xenopus enhancer assays. Next, luciferase assays showed that the non-coding SNVs located in the two hotspot regions of PRDM13 affect cCRE activity, including two NCMD-associated non-coding SNVs that we identified herein. Interestingly, the cCRE containing one of these SNVs was shown to interact with the PRDM13 promoter, demonstrated in vivo activity in Xenopus, and is active at the developmental stage when progenitor cells of the central retina exit mitosis, suggesting that this region is a PRDM13 enhancer. Finally, mining of single-cell transcriptional data of embryonic and adult retina revealed the highest expression of PRDM13 and IRX1 when amacrine cells start to synapse with retinal ganglion cells, supporting the hypothesis that altered PRDM13 or IRX1 expression impairs interactions between these cells during retinogenesis. Overall, this study provides insight into the cis-regulatory mechanisms of NCMD and supports that this condition is a retinal enhanceropathy.

Two novel non-coding single nucleotide variants in the DNase1 hypersensitivity site of PRDM13 causing North Carolina macular dystrophy in Korea.

Purpose: Pathogenic variants in North Carolina macular dystrophy (NCMD) have rarely been reported in the East Asian population. Herein, we reported novel variants of NCMD in 2 Korean families. Methods: The regions associated with NCMD were analyzed with genome sequencing, and variants were filtered based on the minor allele frequency (0.5%) and heterozygosity. Non-coding variants were functionally annotated using multiple computational tools. Results: We identified two rare novel variants, chr6:g.99,598,914T>C (hg38; V17) and chr6:g.99,598,926G>A (hg38; V18) upstream of PRDM13 in families A and B, respectively. In Family 1, Grade 2 NCMD and a best-corrected visual acuity of 20/25 and 20/200 in the right and left eyes, respectively, were observed. In Family B, all affected individuals had Grade 1 NCMD with characteristic confluent drusen at the fovea and a best-corrected visual acuity of 20/20 in both eyes. These two variants are 10-22 bp downstream of the reported V10 variant within the DNase1 hypersensitivity site. This site is associated with progressive bifocal chorioretinal atrophy and congenital posterior polar chorioretinal hypertrophy and lies in the putative enhancer site of PRDM13. Conclusion: We identified two novel NCMD variants in the Korean population and further validated the regulatory role of the DNase1 hypersensitivity site upstream of PRDM13.

CONGENITAL POSTERIOR POLAR CHORIORETINAL HYPOPLASIA: Expansion of the Clinical Spectrum, Mutation, and Its Association With PRDM13.

PURPOSE: To describe a new ocular phenotype in a single Egyptian family associated with a heterozygous noncoding mutation in the North Carolina macular dystrophy (NCMD/MCDR1) locus, likely affecting the PRDM13 gene. METHODS: A retrospective, clinical chart review of 11 members of a four-generation family. Comprehensive ophthalmic examinations included visual acuity, refraction, fundus imaging, spectral-domain optical coherence tomography, and full-field electroretinography. Molecular genetic analysis of the MCDR1 region was performed using whole genome and targeted sequencing. The main outcome measures were DNA sequence variants, clinical, retinal imaging, and electroretinography findings. RESULTS: The five affected adult family members tested carried a single heterozygous mutation in a noncoding region (Chr6:100,046,783A>C) located 7.8 kb upstream of PRDM13. Visual acuity ranged from 20/200 to 20/400. All members had extensive chorioretinal absence/thinning extending outside of the maculae with extensive posterior bowing of the choroid and sclera centered in the macula giving a large macular coloboma-like appearance. Two additional members had cystoid fluid, and one had macular detachment. Full-field electroretinography revealed reduced cone and rod responses in all affected members. CONCLUSION: The phenotype of this disease falls between the spectrum of progressive bifocal chorioretinal atrophy and NCMD. The findings are most consistent with progressive bifocal chorioretinal atrophy with the exception that there is no bifocal nature to the appearance nor is it progressive. Another view is that the phenotype seems to be an extremely severe form of NCMD. Given that this disease falls in between progressive bifocal chorioretinal atrophy and NCMD, we propose calling it congenital posterior polar chorioretinal hypoplasia.

A novel duplication involving PRDM13 in a Turkish family supports its role in North Carolina macular dystrophy (NCMD/MCDR1).

Purpose: To clinically and molecularly investigate a new family with North Carolina macular dystrophy (NCMD) from Turkey, a previously unreported geographic origin for this phenotype. Methods: Clinical ophthalmic examinations, including fundus imaging and spectral domain-optical coherence tomography (SD-OCT), were performed on eight members of a two-generation non-consanguineous family from southern Turkey. Whole genome sequencing (WGS) was performed on two affected subjects, followed by variant filtering and copy number variant (CNV) analysis. Junction PCR and Sanger sequencing were used to confirm and characterize the duplication involving PRDM13 at the nucleotide level. The underlying mechanism was assessed with in silico analyses. Results: The proband presented with lifelong bilateral vision impairment and displayed large grade 3 coloboma-like central macular lesions. Five of her six children showed similar macular malformations, consistent with autosomal dominant NCMD. The severity grades in the six affected individuals from two generations are not evenly distributed. CNV analysis of WGS data of the two affected family members, followed by junction PCR and Sanger sequencing, revealed a novel 56.2 kb tandem duplication involving PRDM13 (chr6:99560265-99616492dup, hg38) at the MCDR1 locus. This duplication cosegregates with the NCMD phenotype in the five affected children. No other (likely) pathogenic variants in known inherited retinal disease genes were found in the WGS data. Bioinformatics analyses of the breakpoints suggest a replicative-based repair mechanism underlying the duplication. Conclusions: We report a novel tandem duplication involving the PRDM13 gene in a family with NCMD from a previously unreported geographic region. The duplication size is the smallest that has been reported thus far and may correlate with the particular phenotype.

CFH and ARMS2 genetic risk determines progression to neovascular age-related macular degeneration after antioxidant and zinc supplementation.

We evaluated the influence of an antioxidant and zinc nutritional supplement [the Age-Related Eye Disease Study (AREDS) formulation] on delaying or preventing progression to neovascular AMD (NV) in persons with age-related macular degeneration (AMD). AREDS subjects (n = 802) with category 3 or 4 AMD at baseline who had been treated with placebo or the AREDS formulation were evaluated for differences in the risk of progression to NV as a function of complement factor H (CFH) and age-related maculopathy susceptibility 2 (ARMS2) genotype groups. We used published genetic grouping: a two-SNP haplotype risk-calling algorithm to assess CFH, and either the single SNP rs10490924 or 372_815del443ins54 to mark ARMS2 risk. Progression risk was determined using the Cox proportional hazard model. Genetics-treatment interaction on NV risk was assessed using a multiiterative bootstrap validation analysis. We identified strong interaction of genetics with AREDS formulation treatment on the development of NV. Individuals with high CFH and no ARMS2 risk alleles and taking the AREDS formulation had increased progression to NV compared with placebo. Those with low CFH risk and high ARMS2 risk had decreased progression risk. Analysis of CFH and ARMS2 genotype groups from a validation dataset reinforces this conclusion. Bootstrapping analysis confirms the presence of a genetics-treatment interaction and suggests that individual treatment response to the AREDS formulation is largely determined by genetics. The AREDS formulation modifies the risk of progression to NV based on individual genetics. Its use should be based on patient-specific genotype.

MACULAR DEGENERATION AND ASPIRIN USE.

PURPOSE: To review current literature of the benefits that aspirin provides for patients' cardiovascular health compared with the risk of AMD worsening. METHODS: We performed a review and critically analyzed six cardiovascular and four ophthalmological trials regarding risks and benefits of aspirin use. The prospective randomized cardiovascular trials had a cumulative 167,580 while the 3 smaller ophthalmological data sets had a cumulative 12,015 subjects. RESULTS: The reviewed meta-analysis literature demonstrated a statistically significant 32% reduction in the risk of nonfatal stroke with regular aspirin users. The study also documented that aspirin users decreased the risk of fatal vascular deaths by 15%. Of the three ophthalmological studies highlighting the adverse affects of aspirin association with AMD, all suggested an exacerbation of AMD without statistical significance and broad confidence bands. CONCLUSION: Overall, the number, size, and quality of the cardiovascular studies recommending aspirin use are far superior to the fewer, smaller and conflicting studies suggesting a possible adverse effect of aspirin use in relation to AMD. The benefits of aspirin usage include preserving the duration and quality of life by decreasing stroke and heart attack risk. These benefits seem to far outweigh the theoretical risks of possibly exacerbating wet AMD, which can be reasonably controlled with anti-VEGF therapy.

North Carolina Macular Dystrophy Is Caused by Dysregulation of the Retinal Transcription Factor PRDM13.

PURPOSE: To identify specific mutations causing North Carolina macular dystrophy (NCMD). DESIGN: Whole-genome sequencing coupled with reverse transcription polymerase chain reaction (RT-PCR) analysis of gene expression in human retinal cells. PARTICIPANTS: A total of 141 members of 12 families with NCMD and 261 unrelated control individuals. METHODS: Genome sequencing was performed on 8 affected individuals from 3 families affected with chromosome 6-linked NCMD (MCDR1) and 2 individuals affected with chromosome 5-linked NCMD (MCDR3). Variants observed in the MCDR1 locus with frequencies <1% in published databases were confirmed using Sanger sequencing. Confirmed variants absent from all published databases were sought in 8 additional MCDR1 families and 261 controls. The RT-PCR analysis of selected genes was performed in stem cell-derived human retinal cells. MAIN OUTCOME MEASURES: Co-segregation of rare genetic variants with disease phenotype. RESULTS: Five sequenced individuals with MCDR1-linked NCMD shared a haplotype of 14 rare variants spanning 1 Mb of the disease-causing allele. One of these variants (V1) was absent from all published databases and all 261 controls, but was found in 5 additional NCMD kindreds. This variant lies in a DNase 1 hypersensitivity site (DHS) upstream of both the PRDM13 and CCNC genes. Sanger sequencing of 1 kb centered on V1 was performed in the remaining 4 NCMD probands, and 2 additional novel single nucleotide variants (V2 in 3 families and V3 in 1 family) were identified in the DHS within 134 bp of the location of V1. A complete duplication of the PRDM13 gene was also discovered in a single family (V4). The RT-PCR analysis of PRDM13 expression in developing retinal cells revealed marked developmental regulation. Next-generation sequencing of 2 individuals with MCDR3-linked NCMD revealed a 900-kb duplication that included the entire IRX1 gene (V5). The 5 mutations V1 to V5 segregated perfectly in the 102 affected and 39 unaffected members of the 12 NCMD families. CONCLUSIONS: We identified 5 rare mutations, each capable of arresting human macular development. Four of these strongly implicate the involvement of PRDM13 in macular development, whereas the pathophysiologic mechanism of the fifth remains unknown but may involve the developmental dysregulation of IRX1.

Onset of an outbreak of Bipolaris hawaiiensis fungal endophthalmitis after intravitreal injections of triamcinolone.

PURPOSE: To report a series of cases with fungal endophthalmitis occurring after intravitreal injection of triamcinolone derived from a single lot prepared by a compounding pharmacy. DESIGN: Retrospective, observational case series. PARTICIPANTS: Seventeen eyes treated with triamcinolone obtained from a single lot subsequently found to be contaminated with Bipolaris hawaiiensis. METHODS: A retrospective chart review in a single retina practice was performed for 15 patients (n = 17 eyes) who received intravitreal injections of triamcinolone obtained from a single compounding pharmacy. Medical records and cytologic and microbiologic results were reviewed from December 2011 through January 2013. MAIN OUTCOME MEASURES: Visual acuity; presence of vitreous cell, anterior chamber cell, or both; and fungal detection in samples obtained by vitreous needle aspiration or vitreous biopsy. RESULTS: Fungal endophthalmitis developed in 82% (14/17) of eyes after intravitreal triamcinolone obtained from the same lot. Median onset was 83 days (range, 6-322 days). Preinjection visual acuity ranged from 20/20 to counting fingers (median, 20/50). Median visual acuity at last follow-up was 20/400 (range, 20/30-no light perception). The most common signs and symptoms included decreased vision (57% [8/14]), vitreous cell (64% [9/14]), and anterior chamber cell (50% [7/14]). Fungus was detected by cytologic or culture examination in 7% (1/14) from initial vitreous tap. By comparison, vitreous samples obtained by pars plana vitrectomy (PPV) resulted in fungus-positive cytologic results in 43% (6/14) of eyes and positive culture results in 36% (5/14) of eyes. All culture-positive specimens (100% [5/5]) were identified as B. hawaiiensis. Overall, fungal infection was confirmed in 57% (8/14) of eyes by either cytologic or microbiologic analysis. CONCLUSIONS: Fungal endophthalmitis resulting from B. hawaiiensis developed in a series of eyes after intravitreal injections of triamcinolone obtained from a single compounding pharmacy. Clinical presentation of infection can be delayed up to 10 months. Vitreous tap may be inadequate, and direct vitreous biopsy by PPV may be preferred to identify fungal endophthalmitis and facilitate prompt diagnosis and treatment.

The 0.19-mg Fluocinolone Acetonide Intravitreal Implant for Diabetic Macular Edema: Intraocular Pressure-Related Effects over 36 Months.

PURPOSE: To evaluate effects of the 0.19-mg fluocinolone acetonide (FAc) intravitreal implant (ILUVIEN) on intraocular pressure (IOP) in patients with diabetic macular edema (DME). DESIGN: Secondary analysis of a 36-month, phase IV, nonrandomized, open-label, observational study. PARTICIPANTS: The study included 202 eyes from 159 patients who received the 0.19-mg FAc implant after a successful prior steroid challenge per the United States label indication. METHODS: Study eyes were assessed for IOP values, incidence of IOP elevations, and best-corrected visual acuity (BCVA) for up to 36 months post-FAc implant. RESULTS: Mean IOP was stable over 36 months post-FAc; IOP change from baseline peaked at 2.12 mmHg at 9 months, then declined to baseline levels. At 36 months, eyes had a 32.5% cumulative probability of an IOP event > 25 mmHg and a 15.6% probability of an IOP event > 30 mmHg (Kaplan-Meier). The probability of requiring IOP-lowering medication at any time by month 36 was 38.3%. A total of 78% of eyes did not have IOP elevations > 25 mmHg if similar values were seen with the previous steroid challenge. Although 7.4% of eyes had an IOP > 30 mmHg during a scheduled study visit, most exceeded this threshold only once (60%). Regardless of IOP status, mean BCVA remained stable. CONCLUSIONS: Over 36 months, the 0.19-mg FAc implant was associated with relatively stable IOPs in patients with DME, and there was no significant impact of IOP elevations identified regarding their effects on long-term visual outcomes. The probability that a prior corticosteroid challenge will not predict an IOP elevation > 25 mmHg over 36 months post-FAc is 22%; therefore, routine IOP monitoring should be scheduled. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found in the Footnotes and Disclosures at the end of this article.

Closure of Macular Holes With Topical Therapy.

Purpose: To report the results of a nonsurgical approach to repair macular holes (MHs). Methods: A retrospective chart review of consecutive patients with MHs from 2018 to 2021 was performed. Topical therapy consisted of a steroidal agent, a nonsteroidal agent, and a carbonic anhydrase inhibitor. Data collected included the size, stage, and duration of the MH; topical agents used and the duration; lens status; and complications. Macular edema was graded on a scale ranging from 0 (no edema) to 4 (large amount of edema) and recorded. Before and after MH closure, the best-corrected visual acuity (BCVA) was measured and converted to logMAR notation. Spectral-domain optical coherence tomography was performed. Results: Seven (54%) of the 13 eyes initially treated topically experienced successful MH closure. Small holes (<230 µm) with a better initial BCVA (0.474 logMAR vs 0.796 logMAR) were more likely to respond favorably to topical therapy (mean 121 µm vs 499 µm). In addition, holes with less surrounding edema responded better. All holes not responding to topical therapy were subsequently closed with pars plana vitrectomy, membrane peeling, and fluid-gas exchange. Conclusions: Topical therapy is a reasonable first-line treatment for MHs, with a better than 50% success rate. This is especially true for small early-onset holes with minimal or no edema. Surgery still had a high success rate after a 1- to 3-month delay while the MH was treated with eyedrops.

A Randomised Phase I Study to Assess the Safety, Tolerability and Pharmacokinetics of Palovarotene Ophthalmic Solution.

BACKGROUND AND OBJECTIVE: Palovarotene, a selective retinoic acid receptor γ agonist, is under investigation for the treatment of dry eye disease. This study aimed to determine the ocular and systemic safety, tolerability and pharmacokinetics of palovarotene ophthalmic solution (PVO-OS) in healthy adults. METHODS: This was a randomised, vehicle-controlled phase I study (NCT04762355; retrospectively registered). Participants received either PVO-OS (at 0.025, 0.05 or 0.10 mg/mL) or a vehicle (placebo-to-match PVO-OS) once-daily or twice-daily for seven consecutive days. Safety was assessed by ocular and systemic assessments. Blood samples for pharmacokinetic assessments were collected before and after dose administration. RESULTS: Thirty-six participants were randomised to PVO-OS and 12 to the vehicle. Overall, 89 treatment-emergent ocular adverse events (TEOAEs) were reported by 22 participants (61.1%) receiving PVO-OS and ten TEOAEs were reported by five participants (41.7%) receiving the vehicle. Erythema, irritation and skin dryness of the eyelid were the most common TEOAEs in participants receiving PVO-OS. The incidence of TEOAEs and eyelid-related findings in the PVO-OS groups increased with ascending dose and frequency compared with participants treated with the vehicle. All TEOAEs were mild (96.6%) or moderate (3.4%) and resolved without sequelae. Plasma palovarotene concentrations were generally measurable for up to 3-4 h for 0.025 mg/mL and 0.05 mg/mL and up to 12 h for 0.10 mg/mL dose regimens, independent of the frequency of administration. CONCLUSIONS: PVO-OS was generally well tolerated at doses up to and including 0.10 mg/mL twice daily. Similar pharmacokinetic profiles were observed for the once-daily and twice-daily regimens following multiple ascending doses of PVO-OS.

New Noncoding Base Pair Mutation at the Identical Locus as the Original NCMD/MCDR1 in a Mexican Family, Suggesting a Mutational Hotspot.

Purpose: To clinically and molecularly study a newly found family with North Carolina macular dystrophy (NCMD/MCDR1) from Mexico. Methods: This retrospective study comprised 6 members of a 3-generation Mexican family with NCMD. Clinical ophthalmic examinations, including fundus imaging, spectral-domain optical coherence tomography, electroretinography, and electrooculography, were performed. Genotyping with polymorphic markers in the MCDR1 region was performed to determine haplotypes. Whole-genome sequencing (WGS) was performed followed by variant filtering and copy number variant analysis. Results: Four subjects from 3 generations were found to have macular abnormalities. The proband presented with lifelong bilateral vision impairment with bilaterally symmetric vitelliform Best disease-like appearing macular lesions. Her 2 children had bilateral large macular coloboma-like malformations, consistent with autosomal dominant NCMD. The 80-year-old mother of the proband had drusen-like lesions consistent with grade 1 NCMD. WGS and subsequent Sanger sequencing found a point mutation at chr6:99593030G>C (hg38) in the noncoding region of the DNase I site thought to be a regulatory element of the retinal transcription factor gene PRDM13. This mutation is the identical site/nucleotide as in the original NCMD family (#765) but is a guanine to cytosine change rather than a guanine to thymine mutation, as found in the original NCMD family. Conclusions: We report a new noncoding mutation at the same locus (chr6:99593030G>C) involving the same DNase I site regulating the retinal transcription factor gene PRDM13. This suggests that this site, chr6:99593030, is a mutational hotspot.

North Carolina Macular Dystrophy: Long-term Follow-up of the Original Family.

PURPOSE: The phenotype of North Carolina macular dystrophy (NCMD) is highly variable and remains poorly appreciated and understood, often causing misdiagnoses in isolated cases. One of the features of NCMD is the general lack of progression despite its original name, "dominant progressive foveal dystrophy," as reported in 1971 by Lefler et al (W.H.L.). The purpose of this study was to report the long-term follow-up of this condition. DESIGN: Systematic, longitudinal, and detailed documentation along with the imaging of the peripheral retina. SUBJECTS: We reexamined 27 of the original family members with NCMD in an office setting 30 to 50 years after they were first reported. METHODS: The evaluation of all the affected subjects included best-corrected visual acuity (BCVA), slit-lamp and dilated-fundus examinations, wide-field fundus and autofluorescent photography, and spectral-domain OCT (SD OCT). Blood was collected for DNA extraction, banking, and sequencing. MAIN OUTCOME MEASURES: Best-corrected visual acuity, slit-lamp and dilated-fundus examinations, wide-field fundus and autofluorescent photography, and SD OCT. RESULTS: The 27 subjects examined were a part of the original family with NCMD that was initially reported in 1971. A point mutation (NC_000006.11:g.100040906G>T) (Hg19) in a noncoding region of a deoxyribonuclease I hypersensitivity binding site was found in all the affected subjects. Nine subjects were the affected children of those originally examined 30 to 50 years ago by Kent W. Small (K.W.S.) and W.H.L., and the remaining 17 subjects (34 eyes) had been examined 30 years previously by K.W.S. Of these 17 subjects (34 eyes), 4 of 34 (11%) eyes showed worsening of vision and evidence of fibrosis due to choroidal neovascular membranes (CNVMs). Fourteen of the 27 (51%) patients showed peripheral retinal drusen, which did not seem to correlate with the severity of the macular disease. CONCLUSIONS: Most patients with NCMD have stable vision and fundus findings throughout their lives. The ones who experienced BCVA decline did so because of the apparent evidence of CNVMs. Patients with grade 2 NCMD seem to be at an increased risk of further or progressive vision loss due to CNVMs. Intravitreal therapy with vascular endothelial growth factor inhibitors may benefit these patients if they are treated in a timely fashion. Peripheral retina drusen of varying degrees of severity were found in slightly more than half of the affected subjects.

Thirty-Year follow-up of an African American family with macular dystrophy of the retina, locus 1 (North Carolina macular dystrophy).

PURPOSE: To describe clinical characteristics, including visual acuity (VA), genetic analysis, and management of complications, over a 30-year period in an African American family with macular dystrophy of the retina, locus 1 (MCDR1), commonly referred to as "North Carolina macular dystrophy." DESIGN: Observational, cohort study. PARTICIPANTS: Twelve family members from a 4-generation pedigree. METHODS: A total of 12 African American patients in an affected family were examined. Clinical examination was documented during 2 different follow-up periods from 1979 to 1982 in 10 patients and from 2005 to 2009 in 11 patients. Genetic analysis was performed in 4 affected members during this time. Foveal microperimetry, fundus autofluorescence, and spectral domain optical coherence tomography (OCT) data were also obtained. MAIN OUTCOME MEASURES: Change in VA of 8 members followed over 3 decades and clinical data and management of complications for all patients. RESULTS: Nine of 11 living family members had classic findings ranging from disease grade 2 (confluent foveal drusen, 8 eyes) to grade 3 (central coloboma-like lesion, 10 eyes). Two members developed choroidal neovascularization (CNV) requiring laser ablation, and 1 member developed non-clearing vitreous hemorrhage and underwent 25-gauge pars plana vitrectomy. Another family member developed exotropia and amblyopia in 1 eye by age 7 years. Those without CNV had no significant change in VA over 30 years. Linkage studies of 4 affected family members showed the same short tandem repeats on markers spanning D6S249 and D6S283 within the MCDR1 region of chromosome 6q16. Microperimetry analysis of an affected member with grade 3 MCDR1 revealed absent function in the region of the central coloboma-like lesions, corresponding to photoreceptor absence on OCT, although there were preserved foveal function and intact photoreceptors adjacent to the lesion. CONCLUSIONS: This African American family shares similar clinical findings as other MCDR1 pedigrees and the same haplotype as the originally described family from North Carolina. Clinical characteristics, including retinal features and stable VA in the absence of amblyopia and CNV, are similar to those in other reports. Eccentric viewing around impaired photoreceptors may explain good VA in patients with clinically severe-appearing macular lesions. Sequencing of the MCDR1 interval may help identify a protein responsible for early macular development. FINANCIAL DISCLOSURE(S): Proprietary or commercial disclosure may be found after the references.

Clinicopathologic findings in Best vitelliform macular dystrophy.

PURPOSE: To correlate the clinical and histopathologic features of Best vitelliform macular dystrophy (BVMD). METHODS: Two eyes were obtained postmortem from a patient with BVMD. The patient's clinical information was reviewed. Series sections of the globes were performed and sequentially stained with hematoxylin-eosin, periodic acid-Schiff or Masson trichrome. A section of the left macula was submitted for electron microscopic processing. Histopathologic findings were reconstructed in a scaled two-dimensional map and compared with fundus photography, fundus autofluorescence (FAF), fundus fluorescein angiography (FFA) and optical coherence tomography (OCT) images. RESULTS: The macular lesion of the right eye was identified as a well-demarcated region with pigment, elevated submacular yellow material and subretinal fluid. This corresponded histopathologically to a well-circumscribed area of RPE hyperplasia, accumulation of lipofuscin in the RPE, deposition of granular material in the photoreceptors, macrophages and drusen. The left eye displayed a 1 disc diameter chorioretinal scar with surrounding shallow fluid and submacular pigment. This corresponded to RPE changes and a fibrocellular proliferation in the choriocapillaris. CONCLUSION: Histopathologic mapping revealed retinal edema, RPE abnormalities, drusen and a chorioretinal scar in BVMD that correlated with the fundus, FFA, FAF and OCT findings.

CHOROIDAL NEOVASCULARIZATION IN NORTH CAROLINA MACULAR DYSTROPHY RESPONSIVE TO ANTI-VASCULAR ENDOTHELIAL GROWTH FACTOR THERAPY.

PURPOSE: To report a new family with North Carolina macular dystrophy including a patient with choroidal neovascularization (CNV). METHODS: Diagnostic modalities included fundus imaging, fluorescein angiography, optical coherence tomography, and genetic testing. The CNV was treated with intravitreal anti-vascular endothelial growth factor according to a treat-and-extend protocol in both eyes. RESULTS: A 60-year-old man presented with North Carolina macular dystrophy with decreasing vision in the left eye and persistently deceased central vision in the right eye. Optical coherence tomography examination showed intraretinal and subretinal fluid consistent with CNV. Genetic testing was performed. Examination of family members showed no signs of CNV. The visual acuity improved from 20/400 to 20/150 in the right eye and from 20/100 to 20/40 in the left eye after intravitreal bevacizumab treatment for CNV. Molecular analysis of the PRDM13 gene revealed a pathogenic heterozygous point mutation. CONCLUSION: Recognition and treatment of CNV in North Carolina macular dystrophy can result in improved vision. Genetic testing of the PRDM13 gene can confirm a molecular diagnosis for North Carolina macular dystrophy.

Best Vitelliform Macular Dystrophy (BVMD) is a phenocopy of North Carolina Macular Dystrophy (NCMD/MCDR1).

PURPOSE: North Carolina Macular Dystrophy (NCMD) and Best Vitelliform Macular Dystrophy (BVMD) are rare autosomal dominant macular dystrophies. Both BVMD and NCMD have markedly variable expressivity. In some individuals, it can be difficult to differentiate between the two disease entities. METHODS: Clinical findings including fundus photography, fundus autofluorescence (FAF), and spectral domain optical coherence tomography (SD-OCT) were evaluated in 5 individuals with NCMD and 3 with BMD. Electrooculography (EOG) was performed in 2 NCMD subjects. Molecular diagnosis was performed using Sanger DNA sequencing. IRB approval was obtained. RESULTS: Five NCMD subjects had clinical findings indistinguishable from three of our BVMD subjects. Molecular diagnosis was confirmed in all but one BVMD subject who had an abnormal EOG prior to discovery of the BEST1 gene. Two NCMD subjects had an abnormal EOG with a normal ERG, which has been considered a unique feature of BVMD. SD-OCT in one BVMD subject demonstrated a small lucency/excavation into the choroid similar to that in grade 3 lesions of NCMD. Two NCMD subjects had elevated sub-macular lesions giving a pseudo-vitelliform appearance on OCT similar to BVMD. CONCLUSION: Best Vitelliform Macular Dystrophy can be a phenocopy of NCMD. There is considerable clinical overlap between NCMD and BVMD, which can cause diagnostic inaccuracies. Our new findings demonstrate that like BVMD, NCMD can also have an abnormal EOG with a normal ERG. The overlapping phenotypes of BVMD with NCMD may provide insights into the mechanisms of the macular changes.