High-hyperopia database, part I: clinical characterisation including morphometric (biometric) differentiation of posterior microphthalmos from nanophthalmos

Ophthalmic manifestations of NAA10-related and NAA15-related neurodevelopmental syndromes: Analysis of cortical visual impairment and refractive errors

NAA10-related (Ogden syndrome) and NAA15-related neurodevelopmental syndrome are known to present with varying degrees of intellectual disability, hypotonia, congenital cardiac abnormalities, seizures, and delayed speech and motor development. However, the ophthalmic manifestations of NAA10 and NAA15 variants are not yet fully characterized or understood. This study analyzed the prevalence of six ophthalmic conditions (cortical visual impairment, myopia, hyperopia, strabismus, nystagmus, and astigmatism) in 67 patients with pathogenic (P) or likely pathogenic (LP) variants in the NAA10 cohort (54 inherited, 10 de novo; 65 missense, 2 frameshift) and 19 patients with (L)P variants in the NAA15 cohort (18 de novo; 8 frameshift, 4 missense, 4 nonsense, and 1 splice site). Patients were interviewed virtually or in-person to collect a comprehensive medical history verified by medical records. These records were then analyzed to calculate the prevalence of these ophthalmic manifestations in each cohort. Analysis revealed a higher prevalence of ophthalmic conditions in our NAA10 cohort compared to existing literature (myopia 25.4% vs. 4.7%; astigmatism 37.3% vs. 13.2%; strabismus 28.4% vs. 3.8%; CVI 22.4% vs. 8.5%, respectively). No statistically significant differences were identified in the prevalence of these conditions between the NAA10 and NAA15 variants. Our study includes novel neuroimaging of 13 NAA10 and 5 NAA15 probands, which provides no clear correlation between globe size and severity of comorbid ophthalmic disease. Finally, anecdotal evidence was compiled to underscore the importance of early ophthalmologic evaluations and therapeutic interventions.

MFRP variations cause nanophthalmos in five Chinese families with distinct phenotypic diversity

Purpose

Nanophthalmos is a congenital ocular structural anomaly that can cause significant visual loss in children. The early diagnosis and then taking appropriate clinical and surgical treatment remains a challenge for many ophthalmologists because of genetic and phenotypic heterogeneity. The objective of this study is to identify the genetic cause of nanophthalmos in the affected families and analyze the clinical phenotype of nanophthalmos with MFRP gene variation (Microphthalmia, isolated; OMIM#611040 and Nanophthalmos 2; OMIM#609549, respectively).

Methods

Comprehensive ophthalmic examinations were performed on participants to confirm the phenotype. The genotype was identified using whole exome sequencing, and further verified the results among other family members by Sanger sequencing. The normal protein structure was constructed using Alphafold. Mutant proteins were visualized using pymol software. Pathogenicity of identified variant was determined by in silico analysis and the guidelines of American College of Medical Genetics and Genomics (ACMG). The relationship between genetic variants and clinical features was analyzed.

Results

Five nanophthalmos families were autosomal recessive, of which four families carried homozygous variants and one family had compound heterozygous variants in the MFRP gene. Both family one and family three carried the homozygous missense variant c.1486G>A (p.Glu496Lys) in the MFRP gene (Clinvar:SCV005060845), which is a novel variant and evaluated as likely pathogenic according to the ACMG guidelines and in silico analysis. The proband of family one presented papilloedema in both eyes, irregular borders, thickened retinas at the posterior pole, tortuous and dilated retinal vessels, and indistinguishable arteries and veins, while the proband of family three presented uveal effusion syndrome-like changes in the right eye. In families one and 3, despite carrying the same gene variant, the probands had completely different clinical phenotypes. The homozygous nonsense variant c.271C>T (p.Gln91Ter) (Clinvar:SCV005060846) of the MFRP gene was detected in family 2, presenting shallow anterior chamber in both eyes, pigmentation of peripheral retina 360° from the equator to the serrated rim showing a clear demarcation from the normal retina in the form of strips. Family four proband carried the homozygous missense variant c.1411G>A (p.Val471Met) in the MFRP gene (Clinvar:SCV005060847), family five proband carried compound heterozygous missense variants c.1486G>A (p.Glu496Lys) and c.602G>T (p.Arg201Leu) in the MFRP gene (Clinvar:SCV005060848), which is a novel variant and evaluated as likely pathogenic according to the ACMG guidelines and in silico analysis, and they all presented clinically with binocular angle-closure glaucoma, family four also had retinal vein occlusion in the right eye during the follow-up.

Conclusion

In this study, pathogenic variants of the MFRP gene were detected in five nanophthalmos families, including two novel variants. It also revealed a distinct phenotypic diversity among five probands harboring variants in the MFRP gene. Our findings extend the phenotype associated with MFRP variants and is helpful for ophthalmologists in early diagnosis and making effective treatment and rehabilitation strategies.

Bisphenol-A in Drinking Water Accelerates Mammary Cancerogenesis and Favors an Immunosuppressive Tumor Microenvironment in BALB-neuT Mice

Bisphenol-A (BPA), a synthetic compound ubiquitously present in the environment, can act as an endocrine disruptor by binding to both canonical and non-canonical estrogen receptors (ERs). Exposure to BPA has been linked to various cancers, in particular, those arising in hormone-targeted tissues such as the breast. In this study, we evaluated the effect of BPA intake through drinking water on ErbB2/neu-driven cancerogenesis in BALB-neuT mice, transgenic for a mutated ErbB2/neu receptor gene, which reproducibly develop carcinomas in all mammary glands. In this model, BPA accelerated mammary cancerogenesis with an increase in the number of tumors per mouse and a concurrent decrease in tumor-free and overall survival. As assessed by immunohistochemistry, BALB-neuT tumors were ER-negative but expressed high levels of the alternative estrogen receptor GPR30, regardless of BPA exposure. On the other hand, BPA exposure resulted in a marked upregulation of progesterone receptors in preinvasive tumors and of Ki67, CD31, and phosphorylated Akt in invasive tumors. Moreover, based on several infiltration markers of immune cells, BPA favored an immunosuppressive tumor microenvironment. Finally, in vitro cell survival studies performed on a cell line established from a BALB-neuT breast carcinoma confirmed that BPA's impact on cancer progression can be particularly relevant after chronic, low-dose exposure.

Clinical update in nanophthalmos: Features, diseases and complications associated

Nanophthalmos is a rare congenital condition of the eyeball that is characterised by a smaller size of the anterior and posterior segments without associated ocular malformations. Typical features that have traditionally been described in these eyes are short axial length, thickened sclera, cornea with a smaller diameter, narrow anterior chamber, and an increased lens to globe volume ratio. However, at present, there is still a lack of recognised diagnostic criteria for nanophthalmos and a classification of its severity. Its clinical relevance stems from the increased risk of multiple ocular conditions, such as high hyperopia, amblyopia, angle-closure glaucoma, retinal detachment, and cataracts. Likewise, in relation to surgery in these eyes, there are particularities in cataract and glaucoma surgery and with a greater risk of associated intra- and postoperative complications. In this way, the treatment of nanophthalmos focuses on controlling the associated eye conditions and reducing and controlling surgical complications. This review aims to update what has been published in recent years regarding nanophthalmos.

Heterozygous variants c.781G>A and c.1066dup of serine protease 56 cause familial nanophthalmos by impairing serine-type endopeptidase activity

BACKGROUND/AIMS

Nanophthalmos is a rare developmental, bilateral, sporadic or hereditary form of microphthalmos. In this study, the heterozygous variants c.781G>A and c.1066dup of the PRSS56 gene were identified in two patients with nanophthalmos. This study reports the clinical manifestation and the underlying pathogenic mechanism.

METHODS

Whole-exome sequencing was performed to identify the pathogenic genes in a Chinese family with nanophthalmos. The molecular simulation was used to predict the structures of wild-type or mutant PRSS56. The PRSS56 wild-type or mutation overexpression cellular models have been constructed accordingly. The subcellular localisation was then observed using immunofluorescence and Western-blot techniques. The Folin-Ciocalteu assay was carried out to evaluate serine-type endopeptidase activity, and a wound-healing assay was used to examine the cellular migratory ability.

RESULTS

The whole-exome sequencing revealed that heterozygous variants c.781G>A and c.1066dup of the PRSS56 gene might contribute to nanophthalmos. Both variants were not identified in the dbSNP, 1000 Genome project or ESP6500 databases. Furthermore, the variants were highly conserved and were involved in biological functions. The mutations result in destructive protein structure and impede serine-type endopeptidase activity, thereby impairing subcellular localisation and cellular migration.

CONCLUSION

The c.781G>A and c.1066dup variants of the PRSS56 gene might negatively affect protein structures, subcellular localisation, serine-type endopeptidase activity and cellular migratory ability. Together, these changes could lead to the development of nanophthalmos. This study identifies the PRSS56 gene as a potential target for nanophthalmos diagnosis and treatment.

A unique case of bilateral nanophthalmos and pigmentary retinal abnormality with unilateral angle closure glaucoma and optic disc pit

BACKGROUND

Microophthalmos or 'dwarf eye' is characterized by an axial length 2 standard deviation less than age-matched controls. It is classified into nanophthalmos, relative anterior microphthalmos, and posterior microphthalmos based on the anterior segment: posterior segment ratio. Nanophthalmos can occur in association with optic disc drusen, foveoschisis, and retinitis pigmentosa, as an autosomal recessive syndrome linked to mutations in the MFRP gene. We report a case of bilateral nanophthalmos and pigmentary retinopathy with angle closure glaucoma and optic disc pit in one eye. We believe this to be the first case presenting with optic disc pit in association with nanophthalmos.

CASE PRESENTATION

A 56-year-old female presented with bilateral small eyes, high hypermetropia, shallow anterior chamber depth, increased lens thickness, mid-peripheral retinal flecks, and macular edema. She also had high intraocular pressure in the right eye, with a disc cupping of 0.9 with an Optic disc pit. The macular edema in the right eye was found to occur in association with the Optic disc pit, whereas, in the left eye, it was associated with intra-retinal hemorrhages and diagnosed as macular branch retinal vein occlusion secondary to hypertension. She was started on anti-glaucoma medications in both eyes and planned for Anti-VEGF injection in the left eye.

CONCLUSION

This case report is unique as it reports an association of Nanophthalmos with Optic Disc pit, with an associated angle closure glaucoma in the same eye, an association which has never been previously reported in the literature.

Anterior Scleral Thickness and Other Dimensions in Nanophthalmos by Swept-Source Optical Coherence Tomography: A Comparative Study

PURPOSE

The purpose of this study is to assess the ocular dimensions of the anterior and posterior segment, including the anterior scleral thickness (AST) in nanophthalmos compared to control eyes.

METHODS

A cross-sectional comparative study was carried out in two groups: 46 eyes of 28 patients with nanophthalmos, defined as axial length (AXL) < 20.5 mm, and 60 eyes of 30 controls paired by age and sex. The AST and ocular wall thickness (OWT) were measured by optical coherence tomography in the temporal and nasal quadrants at 1, 2, and 3 mm from the scleral spur. Also, the anterior chamber depth (ACD), white-to-white (WTW), lens thickness (LT), subfoveal choroidal thickness (SFCT), and retinal thickness (RT) were evaluated.

RESULTS

The mean AXL was 19.3 ± 1.5 mm in the nanophthalmos group and 23.9 ± 1.1 mm in the control group (p < 0.001). The OWT was thicker in all measurement points in nanophthalmos (p < 0.001). There were no differences in the AST measurements between groups, except for the AST1 and the AST3 in the nasal quadrant. ACD was shallower and LT was thicker in nanophthalmos, with WTW being larger in controls (p < 0.001). SFCT and RT were thicker in nanophthalmos compared to healthy individuals (p < 0.001).

CONCLUSIONS

Significant anatomical differences are found in nanophthalmic eyes. They present a shallower ACD; thicker LT, OWT, choroid, and retina; and smaller WTW diameter-although no relevant differences in the AST were observed.

The Genetic Determinants of Axial Length: From Microphthalmia to High Myopia in Childhood

The axial length of the eye is critical for normal visual function by enabling light to precisely focus on the retina. The mean axial length of the adult human eye is 23.5 mm, but the molecular mechanisms regulating ocular axial length remain poorly understood. Underdevelopment can lead to microphthalmia (defined as a small eye with an axial length of less than 19 mm at 1 year of age or less than 21 mm in adulthood) within the first trimester of pregnancy. However, continued overgrowth can lead to axial high myopia (an enlarged eye with an axial length of 26.5 mm or more) at any age. Both conditions show high genetic and phenotypic heterogeneity associated with significant visual morbidity worldwide. More than 90 genes can contribute to microphthalmia, and several hundred genes are associated with myopia, yet diagnostic yields are low. Crucially, the genetic pathways underpinning the specification of eye size are only now being discovered, with evidence suggesting that shared molecular pathways regulate under- or overgrowth of the eye. Improving our mechanistic understanding of axial length determination will help better inform us of genotype-phenotype correlations in both microphthalmia and myopia, dissect gene-environment interactions in myopia, and develop postnatal therapies that may influence overall eye growth.

The Comparison of Soft HydroCone (Toris K) Silicone Hydrogel and Rigid Gas-Permeable Contact Lenses in Patients With Posterior Microphthalmos

OBJECTIVE

To evaluate and compare soft HydroCone (Toris K) silicone hydrogel and rigid gas-permeable contact lenses (RGPCLs) in patients with posterior microphthalmos (PMs), for visual rehabilitation and comfort.

METHODS

The records of 11 patients who were followed up in our hospital with the diagnosis of PM and were fitted with both Toris K and RGPCLs in our contact lens department were reviewed retrospectively. Patient age, gender, axial length (AL), topographic keratometry (K) values and best-corrected visual acuity (BCVA) with both lens types and subjective lens comfort status were recorded.

RESULTS

A total of 22 eyes of 11 patients with a mean age of 20.9±11.1 years were included in the study. The mean AL were 16.01±0.1 and 15.9±0.2 mm in the right and left eyes, respectively. Mean K1 and K2 were 48.6±2.2 and 49.4±2.2 D, respectively. Mean logMAR BCVA of the 22 eyes before contact lens fitting was 0.63±0.56 with spectacle. After Toris K and RGPCLs fitting, mean logMAR BCVA were 0.43±0.20 and 0.35±0.25, respectively. Both lenses provided better visual acuity than spectacles; RGPCLs also provided significantly better visual acuity than HydroCone lens ( P <0.05). Eight of 11 patients (73%) had ocular discomfort with RGPLs, and there was no complaint with Toris K.

CONCLUSIONS

The corneal surfaces are steeper in patients with PMs than in normal population. For that reason, their vision should be rehabilitated by special design keratoconus lenses like Toris K and RGPCLs. Although vision rehabilitation seems better with RGPCLs, these patients prefer Toris K more because of discomfort.

A Comparative Study on the Accuracy of IOL Calculation Formulas in Nanophthalmos and Relative Anterior Microphthalmos

PURPOSE

We sought to compare the prediction accuracy of 6 intraocular lens (IOL) formulas, namely, the Haigis, Hoffer Q, Holladay I, SRK/T, Barrett Universal II and Hoffer QST formulas, in microphthalmic eyes, including those with nanophthalmos and relative anterior microphthalmos (RAM).

DESIGN

Retrospective case series.

METHODS

Twenty-six eyes with nanophthalmos (axial length [AL] 16.84 ± 1.36 mm, range 15.25 mm-19.82 mm) and 12 eyes with RAM (corneal diameter 8.41 ± 0.92 mm, range 7.00 mm-9.50 mm) receiving cataract surgery were included. The IOL Master 500 was used for biometry; thus, lens thickness (LT) was omitted in the IOL power calculation. The mean and median arithmetic and absolute prediction errors (PEs) of the 6 original calculation formulas, the absolute PEs of the 6 formulas after optimization, and the proportion of PEs within ±0.25 diopters (D), ±0.5 D, ±1 D, and ±2 D with each formula were compared. The factors influencing PE were analyzed by multivariate regression.

RESULTS

In the nanophthalmos group, the overall prediction results were shifted to myopia. The original Haigis formula had the smallest median absolute PE (1.61 D, P < 0.001), and the optimized Haigis formula had the highest proportion of PEs within ±0.25 D, ±0.5 D, and ±1 D. In the RAM group, the overall prediction results were not significantly different from 0 (P > .05). No significant difference was found among the formulas before optimization (P = .146) and after optimization (P = .161), but the optimized Barrett Universal II formula had the highest proportion of PEs within ±1 D and ±2 D.

CONCLUSIONS

When omitting the LT parameter in the calculation, the Haigis formula was the most accurate in cataract patients with nanophthalmos (AL <20 mm) among the 6 IOL calculation formulas, and the Barrett Universal II formula had the highest accuracy in cataract patients with RAM (corneal diameter ≤9.5 mm).

Cataract surgery in adult eyes with short axial length

PURPOSE OF REVIEW

Cataract surgery in eyes of patients with short axial length (AL) can be technically challenging and is associated with a high risk of intra- and postoperative complications. Several technical and surgical strategies have been proposed to optimize the visual outcome and decrease the rate of surgical complications and it is important to understand their applications in these cases.

RECENT FINDINGS

Traditional intraocular lens (IOL) measurement formulas in eyes with short AL have reduced reliability. Novel formulas such as the Kane formula provide a better refractive prediction. Surgery can be difficult in short eyes due to the crowdedness of the anterior chamber (AC) and the associated scleral abnormalities increasing the risk of uveal effusion. Surgical techniques such as prophylactic scleral incisions, limited pars plana anterior vitrectomy, and modified hydrodissection, have been shown to facilitate surgery in extremely short eyes and decrease the rate of operative complications. Although cataract surgery improves vision in these cases, short AL and shallow AC have been associated with worse visual outcomes.

SUMMARY

Newer 4 th generation IOL formulas have improved the refractive outcomes of cataract surgery in eyes with short AL. There are multiple evolving surgical strategies for optimizing surgery in these eyes. However, studies on the surgical and visual outcomes of cataract surgery in eyes with short AL are limited by their design and sample size. With further research and continued clinical experiences, we hope to develop evidence-based algorithms for the management of these complex cases.

Clinical presentation and treatment outcomes of an algorithmic approach to uveal effusion syndrome

Purpose

To describe the clinical features and treatment outcomes in spontaneous uveal effusion syndrome (UES).

Methods

A 10-year retrospective chart review of UES patients from a tertiary eye center was carried out. Optical coherence tomography (OCT), fundus fluorescein angiography, and ultrasound biomicroscopy (UBM) scans were performed. UES was managed based on presenting best-corrected visual acuity (BCVA), symptoms, and fundus findings. Patients with secondary causes of uveal effusion were excluded.

Results

Twenty-five eyes of 16 patients were included. Of the 16 patients, 14 (88%) were male and 9 (56%) had bilateral disease. Fifteen of 25 affected eyes had nanophthalmos (axial length (AL) <20.5 mm) and 6 had hyperopia with AL >20.5 mm. The presenting mean distance BCVA was 0.74 ± 0.64 logMAR (mean Snellen: 20/100). Eleven eyes had exudative retinal detachment, and 4 also had exudative choroidal detachment (CD). Choroidal thickness (CT) was increased in 11 eyes on B-scan ultrasonography, and the mean CT was 1.74 ± 0.38 mm. Sub-retinal fluid (SRF) and retinal folds were the most common OCT findings. UBM findings included shallow angles, peripheral CD, and supra-ciliary effusion. A combination of local and systemic corticosteroids was used to successfully treat 12 eyes, 6 needed surgery, and 7 were observed. Partial sclerectomy with anterior chamber maintainer-assisted SRF drainage was the favored surgery. The median period of follow-up was 6.5 months (0.1-76 months), and the mean distance BCVA at the last follow-up was 0.58 ± 0.42 logMAR (mean Snellen: 20/80).

Conclusion

UES can be suitably managed both medically and surgically based on clinical presentation.

Comparison of clinical and biometric characteristics between nanophthalmic children and age-matched controls

Purpose:

To compare the clinical and biometric characteristics of children presenting with nanophthalmos (NO group) with that of age-matched controls (CO group).

Methods:

Electronic medical records of 40 children (<18 years of age) with diagnosis of nanophthalmos (NO), presented to a tertiary center in Tamil Nadu between January 2010 and December 2019, were reviewed and compared with 30 age-matched controls (CO) presenting for routine eye examination between October 2019 and December 2019. Clinical parameters compared were best-corrected visual acuity (BCVA), axial length (AxL), keratometry (K), anterior chamber depth (ACD), lens thickness (LT), retinochoroidal scleral thickness (RCS), corneal diameter, central corneal thickness (CCT), intraocular pressure (IOP), lens axial length factor (LAF), and lens thickness/anterior chamber depth ratio (LT/ACD).

Results:

Mean age of the NO group was 8.95 ± 4.0 years. Mean spherical equivalent (SE) in NO group was 10.87 ± 3.1 D and was inversely correlated to AxL (r = −0.46, P value = 0.003). All biometric parameters (AxL, ACD, LT, RCS, LAF, and LT/ACD), except CCT were significantly different between NO and CO groups. NO group children had 52.5% visual impairment with BCVA ≤ 6/24 and 17.5% had esotropia. Common ocular associations in NO group were amblyopia (64.3%), primary angle-closure glaucoma (PACG) (17.8%), pigmentary retinopathy (14.3%), and retinal detachment (3.6%). Angle-closure disease was seen in 50% of NO group and 30% underwent laser peripheral iridotomy (LPI). There was a significant difference in SE, ACD, and LAF among NO children with AxL <17 mm or >17 mm. Multivariable regression analysis revealed a significant correlation of SE and ACD with AxL.

Conclusion:

Nanophthalmos in children often present as amblyopia with visual impairment and strabismus. NO group with AxL <17 mm, had angle-closure disease as a common association with significantly lower ACD, higher SE, and LAF. All morphometric characteristics, except CCT, were significantly different between NO and CO groups. Close monitoring with serial biometry in NO group is needed for the timely diagnosis and prompt intervention to avoid visual impairment, due to glaucoma.

Genetic analysis assists diagnosis of clinical systemic disease in children with excessive hyperopia

BACKGROUND

A thorough examination (especially those including visual functional evaluation) is very important in children's eye-development during clinical practice, when they encountered with unusual excessive hyperopia especially accompanied with other possible complications. Genetic testing would be beneficial for early differential diagnosis as blood sampling is more convenient than all other structural imaging capture tests or functional tests which need children to cooperate well. Thus genetic testing helps us to filter other possible multi-systemic diseases in children patients with eye disorder.

CASE PRESENTATION

A 3-year-old and an 8-year-old boy, both Chinese children clinically manifested as bilateral excessive hyperopia (≥+10.00), severe amblyopia and exotropia, have been genetically diagnosed as Senior-Loken syndrome-5 (SLSN5) and isolated posterior microphthalmos (MCOP6), respectively.

CONCLUSIONS

This report demonstrates the importance of genetic diagnosis before a clinical consult. When children are too young to cooperate with examinations, genetic testing is valuable for predicting other systemic diseases and eye-related development and for implementing early interventions for the disease.

Comparisons of size of foveal avascular zone area among children with posterior microphthalmos, high hyperopia, and normal eyes

PURPOSE

To determine the area of the surface foveal avascular zone (FAZ) in children with posterior microphthalmos (PM), high hyperopia, and normal eyes using optical coherence tomography (OCT) and OCT angiography (OCTA).

METHODS

Thirty-six children were studied including 6 cases 12 eyes of PM (mean age 9.5 ± 5.2 years), 15 cases 30 eyes of high hyperopia (6.9 ± 1.5 years), and 15 cases 30 eyes of healthy individuals (8.7 ± 1.7 years). The B- and C-scan images in all children were recorded by OCT and OCTA with a scanning area of 3.0 × 3.0 mm centered on the fovea. All images were corrected for axial length differences, and the area of the FAZ surface and central macular thickness (CMT) was measured manually and compared.

RESULTS

The area of FAZ in the PM group was 0.007 ± 0.003 mm², which was significantly smaller than that in the high hyperopia eyes at 0.286 ± 0.108 mm² and healthy eyes at 0.318 ± 0.129 mm² (both P < 0.001). The CMT in the PM group was 401.58 ± 33.60 mm, which was significantly thicker than in the high hyperopia eyes at 202.93 ± 12.28 mm and the normal eyes at 204.43 ± 18.76 mm. The area of the FAZ and CMT in the hyperopia group did not differ significantly from that of the normal healthy eyes.

CONCLUSION

These findings indicate that patients with PM have a hypoplastic macular region, which must be considered in any treatment of these eyes.

Ocular Manifestations in Patients with Fanconi Anemia: A Single-Center Experience Including 106 Patients

OBJECTIVES

To describe the prevalence of acquired ocular manifestations in patients with Fanconi anemia (FA) and to describe and correlate the congenital ocular malformations with the genetic subtypes of the disease.

STUDY DESIGN

This is a cross-sectional observational study of 106 consecutive patients with confirmed diagnosis of FA who were followed at the Hematopoietic Stem Cell Transplantation (HSCT) Service at the Federal University of Paraná, Curitiba, Parana, Brazil. Participants underwent a complete ophthalmologic evaluation and 84 patients underwent ocular ultrasound examination. This study was conducted between November 2014 and August 2017.

RESULTS

The patients ranged in age from 6 months to 43 years of age. Microphthalmia was the most common congenital ocular abnormality (95.2%). A decrease in anthropometric measurements was observed, including palpebral fissure length (78/103 patients [76.5%]), microcornea (48/103 patients [46.6%]), and ptosis (31/103 patients [30.1%]). We identified a new ophthalmic condition in 15 patients with FA, that is, epiretinal tissue on the optic disc. The genetic subtype was identified in 78 patients (79.6%), the FA-A subtype was most prevalent (50%). The most common acquired ocular manifestation (non-graft-versus-host disease [GVHD] related) in patients who did not undergo HSCT (n = 44) was limbal neovascularization (13.6%), whereas in patients who underwent HSCT (n = 62), the GVHD-related manifestation was ocular GVHD (51.6%). The most frequent symptom of ocular GVHD was keratoconjunctivitis sicca (29%).

CONCLUSIONS

Several ocular manifestations were identified in patients with FA.

Treatment of Nanophthalmos-Related Uveal Effusion with Two- vs. Four-Quadrant Partial-Thickness Sclerectomy and Sclerotomy Surgery

Objectives

To report visual and anatomical outcomes following two- or four-quadrant partial-thickness sclerectomy and sclerotomy surgery to treat nanophthalmos (NO)-related uveal effusion (UE).

Materials and Methods

Consecutive patients with NO-related UE were treated with four-quadrant or two-quadrant (for those with associated glaucoma) partial-thickness sclerectomy and sclerotomy surgery. Axial length, extent of UE, preoperative, postoperative, and final best corrected visual acuity (BCVA), time to retinal reattachment, and rates of retinal reattachment and recurrence were noted.

Results

Fourteen eyes of 10 patients with NO-related UE were operated. Retinal detachment (RD) involved mainly the peripheral retina in 7 (50%) eyes, macula in 2 eyes (14.2%), both macula and peripheral retina in 4 eyes (28.6%), and the whole retina in 1 eye. Eleven eyes had four-quadrant surgery, and 3 eyes with associated glaucoma had two-quadrant surgery. External subretinal drainage was performed in one patient who had total RD. The mean preoperative logMAR BCVA of 1.50±0.53 increased significantly to 0.92±0.49 after surgery (p=0.002). Resolution of RD could be achieved with two-quadrant surgery in only 1 of 3 eyes. In the other 2 eyes, retinal reattachment was achieved after a secondary surgery for the remaining two quadrants to complete four-quadrant sclerectomy. Final outcome was total reattachment of the retina in 11 eyes (78.6%), partial reattachment in 1 eye (7.1%), and recurrence of macular detachment in 2 (14.3%) eyes.

Conclusion

Quadrantic partial-thickness sclerectomy and sclerotomy surgery seems effective for treating UE in eyes with NO. Twoquadrant surgery may be tried for mild UE associated with glaucoma to preserve the superior quadrants for future possible glaucoma surgeries, but secondary surgery for the superior quadrants may be needed. External drainage of subretinal fluid may be an option in severe cases to achieve quicker resolution.

Genotype-phenotype spectrum in isolated and syndromic nanophthalmos

PURPOSE

To (i) describe a series of patients with isolated or syndromic nanophthalmos with the underlying genetic causes, including novel pathogenic variants and their functional characterization and (ii) to study the association of retinal dystrophy in patients with MFRP variants, based on a detailed literature review of genotype-phenotype correlations.

METHODS

Patients with nanophthalmos and available family members received a comprehensive ophthalmological examination. Genetic analysis was based on whole-exome sequencing and variant calling in core genes including MFRP, BEST1, TMEM98, PRSS56, CRB1, GJA1, C1QTNF5, MYRF and FAM111A. A minigene assay was performed for functional characterization of a splice site variant.

RESULTS

Seven patients, aged between three and 65 years, from five unrelated families were included. Novel pathogenic variants in MFRP (c.497C>T, c.899-3C>A, c.1180G>A), and PRSS56 (c.1202C>A), and a recurrent de novo variant in FAM111A (c.1706G>A) in a patient with Kenny-Caffey syndrome type 2, were identified. In addition, we report co-inheritance of MFRP-related nanophthalmos and ADAR-related Aicardi-Goutières syndrome.

CONCLUSION

Nanophthalmos is a genetically heterogeneous condition, and the severity of ocular manifestations appears not to correlate with variants in a specific gene. However, retinal dystrophy is only observed in patients harbouring pathogenic MFRP variants. Furthermore, heterozygous carriers of MFRP and PRSS56 should be screened for the presence of high hyperopia. Identifying nanophthalmos as an isolated condition or as part of a syndrome has implications for counselling and can accelerate the interdisciplinary care of patients.

A comparative study on endothelial cell loss in nanophthalmic eyes undergoing cataract surgery by phacoemulsification

Purpose:

The purpose of this study is to compare the endothelial cell loss (ECL) in nanophthalmic eyes and age-matched controls undergoing cataract surgery by phacoemulsification and also to identify the risk factors influencing the endothelial cell density (ECD). This was a prospective comparative interventional case series.

Methods:

We enrolled 19 nanophthalmic eyes (study group) and 42 age-matched cataract controls (control group) undergoing phacoemulsification after meeting the inclusion criteria. Ocular parameters like best-corrected visual acuity, intraocular pressure, pachymetry, specular microscopy, and slit lamp findings were noted preoperatively and at month 1 and 3 postsurgery. All nanophthalmic eyes underwent cataract surgery with concomitant prophylactic posterior sclerostomy.

Results:

The median percentage endothelial loss in nanophthalmic eyes was 4.0 (IQR 0–23.5), 7.4 (IQR 1.0–-22.4) at 1 and 3 months postoperatively compared to 6.3 (IQR 1.7–14.1) and 6.4 (IQR 2.6–-12.1) in age controlled normal eyes (P = 0.94, P = 0.46, respectively). Linear regression analysis showed increasing age as the only variable influencing the percentage decrease in corneal ECD in the study group (P = 0.001). Nanophthalmic eyes with ACD <2.5 mm had a significantly greater reduction in ECD at 3 months postcataract surgery compared to baseline (P = 0.039). Visual outcomes and IOP reduction in the study group with ACD >2.5 mm were significantly better postcataract surgery (P = 0.02 and P = 0.002, respectively).

Conclusion:

The percentage of ECL in nanophthalmic eyes undergoing phacoemulsification is equivalent to normal eyes. However, in the nanophthamic eyes with AC depth <2.5 mm, the percentage cell loss was significantly higher warranting the need for extensive intraoperative care. Increasing age was found to be the only significant risk factor influencing the ECD in short eyes.

Nanophthalmos: An Update on the Biological Parameters and Fundus Abnormalities

Nanophthalmos is a clinical phenotype of simple microphthalmos, in which the anterior and posterior segments of the eyeball do not develop into a normal size without other major ocular or systemic anomalies. Typical clinical manifestations of nanophthalmos include short axial length, thickened sclera, small cornea, shallow anterior chamber, and increased lens-to-eye volume ratio. Currently, there is a lack of recognized diagnostic criteria for nanophthalmos. With the development of eye examination technologies, such as biological measurement and imaging examination, visualization and quantification of the eyeball's shape and structure in nanophthalmos can be realized. New clinical features have been reported, which are of great significance for diagnosing and treating nanophthalmos. This review introduces the related concepts of nanophthalmos and the new developments in its clinical characterization.

Types and Presentation of Refractive Error among Individuals Aged 0-30 Years: Hospital-Based Cross-Sectional Study, Yemen

BACKGROUND

Refractive errors are the most common cause of visual impairment worldwide. Its proportion varied among societies and is considered as a public health challenge. Symptoms and signs associated with refractive errors are the most worrisome and common presentations in the general practice in eye clinics.

AIM

The goal of this study was to determine the types and presentations of refractive error among the 0-30-year-old Yemeni population to aid early identification, diagnosis, referral, and treatment. Methodology. A cross-sectional study including 1,500 out-patients aged from 0 to 30 years attending the ophthalmology clinic in Sanaa, Yemen (between 2012 and 2015). All patients underwent visual acuity examination, autorefractometer, and anterior and posterior segment examination and were grouped according to type, that is, myopia, hyperopia, and astigmatism.

RESULTS

Hyperopia was the most common single diagnosis (53.3%) followed by myopia (33.3%). Astigmatism was uncommon as a single diagnosis (13.4%) but commonly associated with hyperopia or myopia. Myopia was more common in males (42.9%) than in females (25%). Hyperopia was more in females (62.5%) than in males (42.9%). Age groups most affected by refractive errors were 13-18 years (27.7%), 19-24 years (24.8%), and 25-30 years (24.6%), respectively. Decreased vision (53%) was a common presentation in myopia and astigmatism (41.5%) and less in hyperopia (39.6%). Headache was common in astigmatism (56%), hyperopia (28.8%), and myopia (17.8%). Muscle imbalance, namely, exotropia (27.2%), is mainly found in myopia and esotropia (24.3%) in hyperopia.

CONCLUSIONS

In addition to decreased vision, our patients with refractive errors mostly complain of headaches with clear variations with age and type of refractive error. Early identification and proper categorization of refractive errors by age, gender, and other demographics by general physicians in primary care can better deduce and make useful referrals to eye specialists.

Posterior segment abnormalities in posterior microphthalmos

Purpose

We report a case of posterior microphthalmos with characteristic papillomacular retinal folds, pigmentary retinopathy, and optic disc drusen.

Observations

A 19-year-old female presented with decreased visual acuity and was found to have bilateral posterior microphthalmos with the presence of papillomacular retinal folds, crowded optic nerves with buried disc drusen, and peripheral retinal pigmentary changes. Optical coherence tomography showed presence of retinal folds involving the inner retinal layers and loss of foveal contour.

Conclusions and Importance

Posterior microphthalmos can present with an array of unique clinical findings involving the posterior segment. It is important to recognize these findings as these patients often have decreased visual acuity and are at risk for the development of other posterior complications.

The Pathogenesis and Treatment of Complications in Nanophthalmos

Microphthalmos is a type of developmental disorder ophthalmopathy, which can occur isolated or combined with other ocular malformations and can occur secondary to a systemic syndrome. Nanophthalmos is one of the clinical phenotypes of microphthalmos. Due to the special and complex structure of nanophthalmic eyes, the disorder is often associated with many complications, including high hyperopia, angle-closure glaucoma, and uveal effusion syndrome. The management of these complications is challenging, and conventional therapeutic methods are often ineffective in treating them. The purpose of this paper was to review the concept of nanophthalmos and present the latest progress in the study of the pathogenesis and treatment of its complications. As it is considerably challenging for ophthalmologists to prevent or treat these nanophthalmos complications, timely diagnosis and a suitable clinical treatment plan are vital to ensure that nanophthalmos patients are treated and managed effectively.

A novel MFRP gene variant in a family with posterior microphthalmos, retinitis pigmentosa, foveoschisis, and foveal hypoplasia

BACKGROUND

To characterize the phenotype and genotype of a syndrome associating posterior microphthalmos (PM), retinitis pigmentosa (RP), foveoschisis, and foveal hypoplasia (FH) in a consanguineous Portuguese family.

MATERIALS AND METHODS

Three siblings were studied and underwent comprehensive eye examinations for best-corrected visual acuity, axial length, refractive error, B-mode ultrasound, electroretinography, retinography, fluorescein angiography (FA), kinetic visual field (VF), and optical coherence tomography (OCT). Molecular analysis was performed by Sanger sequencing of the entire coding region of the MFRP gene.

RESULTS

All members presented nyctalopia, decreased visual acuity, and constriction of the VF, as well as bilateral shortening of the posterior ocular segment and normal anterior segment dimensions. The fundoscopy and ERG results were compatible with RP. Macular OCT analysis revealed schisis of the outer retinal layer, FH, as well as retinal and choroidal folds. We identified a homozygous mutation in intron 9 of the membrane frizzled-related protein (MFRP) gene (c.1124 + 1 G > A).

CONCLUSIONS

Our study shows a family with PM and RP due to a mutation in the MFRP gene. The relationship has previously been proven, but this specific mutation has never been described. These gene mutations show wide phenotypic variability, being evident in the presence of foveoschisis, retinal and choroidal folds, and FH, other than PM and RP.

Clinical spectrum and treatment outcomes of patients with nanophthalmos

PURPOSE

To study the varied demographic, visual and clinical presentation of patients with nanophthalmos.

METHODS

Retrospective chart review of 144 consecutive subjects with nanophthalmos from January 2010 to January 2018 was done. Demographic details, visual acuity, refractive status, clinical parameters and surgical data were collected.

RESULTS

Mean age at presentation was 48.76 ± 15.99 years (5-74 years) and 55.6% were females. Median BCVA was 0.78 (6/36 Snellen equivalent) and median spherical equivalent was +10.0 (5.7-12.5) . Amblyopia was seen in 30.0% patients. Legal blindness was present in 16.7% of the study population. The mean IOP was 18.38 ± 9.38 mmHg. Angle closure disease was present in 67.7% and 35.7% had angle closure glaucoma. Presence of peripheral anterior synechia had higher odds (OR = 3.66; 95% CI, 1.71-7.84) of associated glaucoma. The mean axial length, 17.64 ± 1.74 mm was inversely correlated to the mean Retinochoroidal Sclera(RCS) thickness of 1.99 ± 0.25 mm (r = -0.28, p value < 0.001).All patients who had undergone surgery for glaucoma (n = 11) had associated intra or postoperative complication. Cataract surgery by manual small incision had more complications than Phacoemulsification (p value = 0.001). Occurrence of uveal effusion was significantly lower in eyes which underwent sclerostomy (p = 0.04) CONCLUSION: Nanophthalmos is a rare disorder with varying degree of visual impairment & amblyopia. High incidence of angle closure glaucoma was observed. Surgical management for glaucoma is often challenging with frequent complications. Cataract surgery by phacoemulsification had significantly lower complications than SICS and performing a concomitant sclerostomy reduced the occurrence of uveal effusions.

Pseudodominant Nanophthalmos in a Roma Family Caused by a Novel PRSS56 Variant

Background

The aim of the study was to identify the molecular genetic cause of two different Mendelian traits with ocular involvement present in the members of a single consanguineous Czech Roma family.

Methods

We have performed ocular examination and review of medical records in two individuals diagnosed with nanophthalmos (proband and her father) and one individual followed for bilateral congenital cataract and microcornea (uncle of the proband). DNA of subjects with nanophthalmos was analysed by exome sequencing. Sanger sequencing was applied for targeted screening of potentially pathogenic variants and to follow segregation of identified variants within the family.

Results

A homozygous variant c.1509G>C; p.(Met503Ile), in PRSS56 was found in the two individuals affected with nanophthalmos. The change was absent from the gnomAD dataset, but two out of 118 control Roma individuals were also shown to be heterozygous carriers. Analysis of single nucleotide polymorphisms in linkage disequilibrium with the c.1509G>C in PRSS56 suggested a shared chromosomal segment. The nanophthalmos phenotype, characterized in detail in the younger individual, encompassed bilateral corneal steepening, retinal folds, buried optic head drusen, and restricted visual fields, but no signs of retinal dystrophy. A known pathogenic founder CTDP1 variant c.863+389C>T in a homozygous state was identified in the other family member confirming the suspected diagnosis of congenital cataracts, facial dysmorphism, and demyelinating neuropathy syndrome.

Conclusions

Herein, we report the first occurrence of nanophthalmos in the Roma population. We have identified pseudodominant inheritance for this phenotype caused by a novel variant in PRSS56, representing a possible founder effect. Despite advances in genetic technologies such as exome sequencing, careful phenotype evaluation in patients from an isolated population, along with an awareness of population-specific founder effects, is necessary to ensure that accurate molecular diagnoses are made.

Clinical characteristics and OCT analysis of a case series of posterior microphthalmos

Posterior microphthalmos is a rare condition that can be found in paediatric patients with increased farsightedness and reduced vision. A retrospective study is presented of 5cases of posterior microphthalmia aged between 4 and 13 years. The following parameters were obtained: visual acuity, cycloplegic refractive error, optical biometry, slit lamp examination, intraocular pressure, and ocular ultrasound. The refraction, axial length and average visual acuity was+15.35 Dp, 16.20mm and 0.13, respectively. The fundus was examined, optical coherence tomography was performed, and also retinography and fluorescein angiography in one case. In all cases, the absence of foveal depression and different morphotypes of the papillo-macular fold were observed in the tomography. In the absence of a specific treatment, the appropriate detection, management, and monitoring of this disease is important to improve and maintain the vision of patients and recognise possible complications.

Novel mutations in MFRP and PRSS56 are associated with posterior microphthalmos

Background: Biallelic pathogenic variants in MFRP and PRSS56 genes can be responsible for nanophthalmos (NO) or posterior microphthalmos (PM). This study describes detailed clinical and molecular findings in a series of five patients affected by PM from four unrelated families.Materials and Methods: All patients underwent a complete ophthalmological and genetic evaluation. For proper and deep phenotyping a multimodal instrumental approach was used for all cases: B-scan ultrasound, spectral domain optical coherence tomography (SD-OCT), fundus retinal imaging and anterior segment data were obtained. Molecular analysis of PRSS56 and MFRP genes was performed with Next-Generation Sequencing (NGS) methodology and segregation analysis on parents and one affected sibling was performed with Sanger sequencing.Results: A very high hyperopia of +14.00D or more was the main refractive error and macular abnormalities were identified in all patients. Axial length ranged from 15.3 mm to 17.86 mm (mean 16.58 mm) and age at first presentation ranged from 6 to 36 months (mean 18 months). Anterior chamber depth was within normal values, according to age, while total axial length was severely reduced in all patients. All our patients met the diagnostic criteria for PM. Three patients, including a pair of siblings, carried compound heterozygous mutations in the PRSS56 gene; in the other two patients, one homozygous or two compound heterozygous mutations in the MFRP gene were detected.Conclusion: Our study describes four novel mutations in the PRSS56 gene and one in the MFRP gene in patients with non-syndromic posterior microphthalmos. Proper genotype-phenotype correlation and early diagnosis could lead to good functional results.

Nanophthalmos in children: morphometric and clinical characterization

PURPOSE

To report clinical and morphometric characteristics of children with nanophthalmos and to identify possible risk factors associated with occludable angles.

METHODS

The medical records of children (<18 years of age) with nanophthalmos examined from January 2016 to December 2016 were reviewed retrospectively. Demographic and examination details, including cycloplegic refraction, best-corrected visual acuity, intraocular pressure (IOP), gonioscopy, and fundus examination, were extracted for analysis. Biometric data included axial length, anterior chamber depth, and lens thickness. Subgroup data from children with occludable and open angles on gonioscopy were compared.

RESULTS

A total of 75 children were included. Mean age at presentation was 10.92 ± 4.97 years. Mean spherical equivalent was +13.31 ± 2.69 D. Best-corrected visual acuity was 20/40 or better in 26 eyes (35%). Ametropic amblyopia was leading cause of visual impairment in our series. IOP was within normal limits (10-21 mm Hg) in 73 subjects and above normal in 2. Of the 75 children, 17 had occludable angles. Posterior segment anomalies were found in 28. Mean axial length was 16.88 ± 1.5 mm, mean anterior chamber depth was 3.00 ± 0.5 mm, and mean lens thickness was 3.9 ± 0.5 mm. The ratio of lens thickness to axial length was 0.253 ± 0.025 in subjects with occludable angles; 0.226 ± 0.038, in those with open angle. A ratio of >0.239 increased the risk of having angle closure by nearly three times.

CONCLUSIONS

In this study cohort, nanophthalmos was characterized by short axial length and high hyperopia, with shallow anterior chamber. Nearly 20% of children had occludable angles requiring intervention. Clinicians should monitor the ratio of lens thickness to axial length to ensure that angle closure is prevented.

Multimodal imaging in posterior microphthalmos

Purpose

To evaluate the multimodal imaging including optical coherence tomography angiography (OCTA) findings in patients with posterior microphthalmos (PM).

Methods

In an observational case series, four eyes of two patients, eight and twenty-three years old, with clinical proven PM underwent complete ophthalmic examination, including refraction, fluorescein angiography, optical coherence tomography (OCT), OCTA, B-scan ultrasonography, axial length measurement using IOL Master optical measuring, and Pentacam evaluation.

Results

Both patients were high hyperopic with partial thickness retinal fold in macula, retinoschisis, and foveal hypoplasia. Axial length was less than 17 mm with scleral thickening in all eyes. OCTA showed absence of foveal avascular zone (FAZ) in both superficial and deep capillary plexuses. Pentacam showed corneal steepness, shallow anterior chamber, and low anterior chamber volume.

Conclusion

OCTA findings showed absence of avascular zone in both superficial and deep capillary plexuses, while OCT shows partial thickness retinal fold and retinoschisis.

Variants in myelin regulatory factor (MYRF) cause autosomal dominant and syndromic nanophthalmos in humans and retinal degeneration in mice

Nanophthalmos is a rare, potentially devastating eye condition characterized by small eyes with relatively normal anatomy, a high hyperopic refractive error, and frequent association with angle closure glaucoma and vision loss. The condition constitutes the extreme of hyperopia or farsightedness, a common refractive error that is associated with strabismus and amblyopia in children. NNO1 was the first mapped nanophthalmos locus. We used combined pooled exome sequencing and strong linkage data in the large family used to map this locus to identify a canonical splice site alteration upstream of the last exon of the gene encoding myelin regulatory factor (MYRF c.3376-1G>A), a membrane bound transcription factor that undergoes autoproteolytic cleavage for nuclear localization. This variant produced a stable RNA transcript, leading to a frameshift mutation p.Gly1126Valfs*31 in the C-terminus of the protein. In addition, we identified an early truncating MYRF frameshift mutation, c.769dupC (p.S264QfsX74), in a patient with extreme axial hyperopia and syndromic features. Myrf conditional knockout mice (CKO) developed depigmentation of the retinal pigment epithelium (RPE) and retinal degeneration supporting a role of this gene in retinal and RPE development. Furthermore, we demonstrated the reduced expression of Tmem98, another known nanophthalmos gene, in Myrf CKO mice, and the physical interaction of MYRF with TMEM98. Our study establishes MYRF as a nanophthalmos gene and uncovers a new pathway for eye growth and development.

Comparison between Refractive Outcome of Primary Piggyback Intraocular Lens versus Secondary Lens Iris Claw Lens in Posterior Microphthalmos

Purpose

To compare the refractive outcome of 2 different methods of intraocular lens implantation in cases of posterior microphthalmos, primary piggyback IOLs versus secondary iris claw lenses.

Methods

This study was a retrospective interventional comparative study that included 60 eyes of 30 patients. The included patients had bilateral microphthalmos with high axial hyperopia and had undergone a lens-based surgical procedure for hyperopia correction. The included patients were equally divided into two groups. The first group had undergone refractive lens exchange (RLE) with primary piggyback IOL implantation. The second group undergone RLE with maximum available IOL power implanted followed by a secondary implantation of Artisan iris-fixated IOL (Ophtec B.V., Groningen, the Netherlands).

Results

The 2 groups were highly comparable to each other regarding the mean age, axial length (AL), manifest refraction (MR), and K readings. Postoperatively, there was a statistically significant difference between the 2 groups regarding the manifest refraction spherical equivalent (MRSE), mean absolute error (MAE), and uncorrected distance visual acuity (UDVA). There was no significant difference between the 2 groups regarding the CDVA. At 36 months, 20% and 73% of the eyes were within ±0.5 D of intended refraction at 36 months in 1ry piggyback and 2ry Artisan groups, respectively. Fifty-three percent and 93% of the eyes were within ±1.0 D of intended refraction at 36 months in 1ry piggyback and 2ry Artisan groups, respectively (p=0.001).

Conclusion

Secondary procedure with implantation of iris-fixated intraocular lens yielded very good results for treatment of axial hyperopia in cases of posterior microphthalmos. The primary piggyback IOL showed less satisfactory results with cases of under correction and the possible complication of interlenticular opacification. Both groups showed good safety parameters.

Ocular findings in posterior microphthalmos

AIM

To report a critical case series of six patients with posterior microphthalmos (PM).

METHOD

Complete ophthalmologic examinations of all patients were performed using best-corrected visual acuity (BCVA), cycloplegic refraction, applanation tonometry, slit lamp biomicroscopy of the anterior segment, fundoscopy, A and B mode ultrasonography (USG), keratometry, and optic coherence tomography (OCT).

RESULTS

The most significant clinical characteristics of male patients aged 10-25 years was the presence of shorter posterior segments (mean: 15.27-18.91 mm) accompanying high hyperopia (mean +9.00 - +18.50 diopter) despite the normal anterior segment findings. The BCVA ranged between 20/320 and 40/100. Retinal folds were detected bilaterally on the papillomacular band in all patients. Although neurosensory retina was included in the fold in OCT images, retinal pigment epithelium, choroid, and sclera were not included in the fold. Pigmentary retinopathy was detected in one patient.

CONCLUSION

Despite normal anterior segment, posterior microphthalmos is characterized with high hyperopia, and shorter axial length and bilateral papillomacular retinal fold. Refractive amblyopia, uveal effusion syndrome, retinal detachment and macular hole are complications that can be corrected. Posterior microphthalmos must be kept in mind in patients with a normal anterior segment, and high hyperopia.

[Glaucoma and nanophthalmos]

The term nanophthalmos refers to a clinically small eye that appears morphologically normal. A nanophthalmos is characterized by hyperopia but can also be associated with various secondary pathologies, such as angle-closure glaucoma. In particular, the perioperative risks associated with a nanophthalmic eye necessitate examination of the anatomical characteristics, which can result from the disproportional size of intraocular tissues despite structural normality. These include a small anterior chamber depth, scleral thickening and anomalies of the vein plexus, which are predisposing factors for the formation of angle-closure glaucoma. The resulting therapeutic challenges in the nanophthalmic eye can be countered with iridectomy, lensectomy, vitrectomy and cyclophotocoagulation. The definition, genetics and clinical findings of nanophthalmos are discussed with a focus on the complication of glaucoma and its treatment.

Clinical features of posterior microphthalmic and nanophthalmic eyes

AIM

To clinically differentiate nanophthalmos (NO) and posterior microphthalmos (PM) and to explore the mechanisms related to papillomacular folds (PMF).

METHODS

Medical records of 34 unrelated patients with microphthalmos (54 eyes) from April 2009 to October 2017 were retrospectively reviewed.

RESULTS

Fourteen eyes of 7 unrelated patients with NO and PM were included in the study. The presenting age of the NO cohort was significantly higher compared with the PM cohort (NO: 27±16y; PM: 3.7±0.6y). PMF was more likely to occur in cases with PM than in NO (25% in NO, 100% in PM). The anatomic features of PMF from optical coherence tomography (OCT) included: ganglion cell layer, inner plexiform layer, inner nuclear layer, outer plexiform layer and outer nuclear layer. In eyes without an apparent PMF (these were all NO eyes), rudimentary fovea without a foveal pit was noted. Four eyes that were NO developed angle closure glaucoma. Three NO eyes developed exudative retinal detachment and were successfully treated with lamellar sclerectomy.

CONCLUSION

Posterior segment changes are pervasive both in PM and NO. Complications like angle closure glaucoma and exudative retinal detachment are likely to occur in eyes with NO but not with PM. Detailed OCT analysis found that PMF was partially a neural retinal issue, suggesting that redundancy of retinal issues involved only inner retinal layers.

Unmeasurable small size superficial and deep foveal avascular zone in nanophthalmos: the Collaborative Nanophthalmos OCTA Study

Aim

To study the macular structure and vasculature in consecutive nanophthalmic eyes using optical coherence tomography angiography.

Methods

This is a prospective, multicentre, cross-sectional study of patients with nanophthalmos (one or both eyes). The superficial and deep foveal avascular zones (FAZ) were measured both manually and with the machine’s built-in automated measurement tool. Correlations between best corrected visual acuity (BCVA), central macular thickness (CMT) and subfoveolar choroidal thickness (SFCT) were calculated.

Results

Sixty-five eyes of 35 subjects (16 men and 19 women) with a mean age of 37.4 years were analysed. The mean±SD of refractive error was 14.3±3.2 dioptres, axial length was 16.4±1.6 mm, CMT was 410.2±128.3 µm and SFCT was 450.1±108.3 µm. FAZ was unmeasurable small size in both the superficial and deep capillary plexus in all eyes, along with tortuosity of the superficial foveal capillaries and large vessels. Foveal folds were present in 29 eyes. Disc drusen was detected in 27 eyes and was absent in 31 eyes, while fundus autofluorescence was positive in 17 and negative in 24 eyes. BCVA varied from 20/20 to 20/800, with a mean of 20/76. Using Spearman’s correlation, logarithm of the minimum angle of resolution BCVA correlated negatively with axial length (r=−0.30; p=0.015).

Conclusions

FAZ attenuation, capillary tortuosity, foveal folds and thickened subfoveal choroid characterise the nanophthalmic macula. These findings may result from a redundant retina and the absence of apoptotic foveolar retraction because of developmental arrest of the optic vesicle after closure of the embryonic fissure.

Nanophthalmos: A Review of the Clinical Spectrum and Genetics

Nanophthalmos is a clinical spectrum of disorders with a phenotypically small but structurally normal eye. These disorders present significant clinical challenges to ophthalmologists due to a high rate of secondary angle-closure glaucoma, spontaneous choroidal effusions, and perioperative complications with cataract and retinal surgeries. Nanophthalmos may present as a sporadic or familial disorder, with autosomal-dominant or recessive inheritance. To date, five genes (i.e., MFRP, TMEM98, PRSS56, BEST1, and CRB1) and two loci have been implicated in familial forms of nanophthalmos. Here, we review the definition of nanophthalmos, the clinical and pathogenic features of the condition, and the genetics of this disorder.

Retinal findings in a patient of French ancestry with CABP4-related retinal disease

INTRODUCTION

CABP4-related retinal dysfunction is a cone-rod synaptic transmission disorder with electronegative electroretinogram (ERG) waveform. It is a rare retinal dysfunction that can be classified into the incomplete form of congenital stationary night blindness. Absent foveal reflex and overall foveal thinning were previously reported, but in most cases the fundus appearance was described as nearly normal. We report here peculiar macular changes in a patient of French ancestry harbouring CABP4 mutations.

METHODS

Complete ocular examination and full-field ERG were performed at the initial presentation and follow-up. Multimodal fundus imagining, including spectral-domain optical coherence tomography, colour, infrared reflectance and short-wavelength autofluorescence photographs, was performed during follow-up visits.

RESULTS

A 7-month-old infant was addressed to our department for visual unresponsiveness and nystagmus. ERG had an electronegative waveform, even for light-adapted stimuli, thus supporting the diagnosis of photoreceptor-bipolar cell transmission disorder. Genetic investigations discovered a compound heterozygous mutation in CABP4: c.646C > T, p.Arg216*/c.673C > T, p.Arg225*. Multimodal fundus imaging, performed at follow-up visits, showed fine radial folds at the vitreomacular interface and dark foveal dots in both eyes. Optic coherence tomography revealed a focal foveal ellipsoid zone gap.

DISCUSSION

Initial presentation was misleading with Leber congenital amaurosis. The electronegative ERG waveform reoriented the genetic investigations and thus establishing a correct diagnosis. To the best of our knowledge, the peculiar fundus changes observed in our patient were never reported before. We hypothesized that a foveal ellipsoid zone interruption discovered in our patient could reflect mostly a cone dysfunction. It was unclear whether the fine radial folds in both maculae were linked with high hyperopia or were an intrinsic feature of the retinal disease.

CONCLUSION

CABP4-related retinal disease is a cone-rod system disorder with possible foveal abnormalities.

Tietz/Waardenburg type 2A syndrome associated with posterior microphthalmos in two unrelated patients with novel MITF gene mutations

Tietz syndrome and Waardenburg syndrome type 2A are allelic conditions caused by MITF mutations. Tietz syndrome is inherited in an autosomal dominant pattern and is characterized by congenital deafness and generalized skin, hair, and eye hypopigmentation, while Waardenburg syndrome type 2A typically includes variable degrees of sensorineural hearing loss and patches of de-pigmented skin, hair, and irides. In this paper, we report two unrelated families with MITF mutations. The first family showed an autosomal dominant pattern and variable expressivity. The second patient was isolated. MITF gene analysis in the first family demonstrated a c.648A>C heterozygous mutation in exon 8 c.648A>C; p. (R216S), while in the isolated patient, an apparently de novo heterozygous c.1183_1184insG truncating mutation was demonstrated in exon 10. All patients except one had bilateral reduced ocular anteroposterior axial length and a high hyperopic refractive error corresponding to posterior microphthalmos, features that have not been described as part of the disease. Our results suggest that posterior microphthalmos might be part of the clinical characteristics of Tietz/Waardenburg syndrome type 2A and expand both the clinical and molecular spectrum of the disease. © 2016 Wiley Periodicals, Inc.