Management of glaucoma in patients with nanophthalmos

Nanophthalmos-Associated MYRF gene mutation facilitates intraocular inflammation in mice

PURPOSE

Patients with nanophthalmos might be prone to developing intraocular inflammation following an acute glaucoma attack. Here, we aimed to investigate the role of MYRF in intraocular inflammation by modeling the mutation in mice.

METHODS

Nanophthalmos frameshift mutation of Myrf was introduced into the mouse genome with the CRISPR-Cas9 system. Signaling pathways in eye tissues were delineated using RNA sequencing and Kyoto Encyclopedia of Genes and Genomes (KEGG) pathway enrichment analysis. Intraocular inflammation was induced by a lipopolysaccharide (LPS) intravitreal injection. Dexamethasone (DEX) was administered systemically and locally a week before the LPS injection. The anterior segment clinical scores of the mice were examined 24 h after the LPS injection. Infiltrating inflammatory cells were evaluated with histopathology and immunofluorescence. The mRNA levels of inflammatory cytokines were quantified with reverse transcription-quantitative PCR (RT-qPCR) and the corresponding protein concentrations using enzyme-linked immunosorbent assay (ELISA).

RESULTS

Many inflammation-associated signaling pathways were enriched in Myrf mut/+ mice ocular tissues. Clinical scores of Myrf mut/+ mice were significantly higher than those of Myrf +/+ mice 24 h after LPS administration. Histological examination demonstrated high inflammatory cell infiltration in the anterior and vitreous chambers in Myrf mut/+ mice, with numerous CD45+ and CD11b+ inflammatory cells. Moreover, enhanced expression of inflammatory cytokines MCP-1, TGF-β, and IL-1β in eyes and aqueous humor of Myrf mut/+ mice was detected. Remarkably, pretreating Myrf mut/+ mice with DEX relieved the intraocular inflammation.

CONCLUSION

Nanophthalmos-associated MYRF mutation renders mouse eyes more susceptible to inflammation. Dexamethasone treatment ameliorates the inflammatory response.

Primary Transscleral Diode Laser Cyclophotocoagulation for Management of Glaucoma in Nanophthalmic Eyes

PURPOSE

The aim of this study was to assess the efficacy and safety of double-row transscleral cyclophotocoagulation in controlling intraocular pressure in patients with secondary angle closure glaucoma due to nanophthalmos, not being controlled by medical therapy.

PATIENTS AND METHODS

A prospective case series study that included 13 eyes of 8 patients diagnosed with secondary angle closure glaucoma due to nanophthalmos at the Giza Eye Subspeciality Center, treated by 24 cyclodiode applications in a double-row technique. Success was defined as complete success by control of intraocular pressure <21 mm Hg without medication and qualified success in which control of pressure <21 mm Hg achieved with 1 or 2 medications.

RESULTS

The average reduction in intraocular pressure at 3 months was 57.3±20.14% and at 6 months 44.5±32%, with an average eye drop intake of 1.3±0.8 drops. There was a significant reduction of intraocular pressure at 6 months compared with the preprocedure pressure ( P =0.01). Complete success achieved in 3 eyes, pressure controlled without any medication, and qualified success in 9 eyes.

CONCLUSION

Transscleral cyclophotocoagulation is a safe and effective primary therapy for managing glaucoma in nanophthalmic eyes.

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.

Pathogenic variants of MFRP and PRSS56 genes are major causes of nanophthalmos in Japanese patients

BACKGROUND

Nanophthalmos (NNO) is a rare condition with significantly shorter axial length than normal. Several genes are known to cause NNO, among them the MFRP and PRSS56 genes have been reported to cause majority of NNOs. The purpose of this study was to determine the genetic basis of Japanese patients with NNO.

MATERIALS AND METHODS

We studied seven patients with NNO. Whole exome sequencing (WES) and Sanger sequencing were performed to determine the variants causing the NNO. We also reviewed the medical charts of the patients to determine the phenotype of these seven patients.

RESULTS

WES revealed that four patients from three families carried homozygous frameshift variants of the PRSS56 gene (c.1066dupC). Two novel variants of the MFRP gene were detected in the other two patients: one proband had a homozygous missense variant (c.1486 G>A) and the other had a compound heterozygous variant (c.1486 G>A and c.662_663insT). The axial length of the eight eyes with the PRSS56 variant was 15.69 ± 0.48 mm (mean ± SD) and that for the 4 eyes with the MFRP variant was 15.63 ± 0.69 mm. Three of the six cases with the PRSS56 or MFRP variant had the uveal effusion syndrome.

CONCLUSIONS

NNOs in Japanese patients are caused by variants of the PRSS56 and MFRP genes as in other ethnic populations. In addition, two new variants of the MFRP gene were found in our cohort. The phenotypes and anomalies in Japanese patients with NNO were similar to those reported for other ethnic populations.

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.

Outcomes of combined phacoemulsification, anterior vitrectomy, and sclerectomy in nanophthalmic eyes with glaucoma

OBJECTIVES

To compare the long-term efficacy and safety of combined phacoemulsification, anterior vitrectomy, and sclerectomy (triple procedure surgery, TS); combined phacoemulsification and anterior vitrectomy (double procedure surgery, DS); and filtering surgery (FS) in nanophthalmos with angle-closure glaucoma (NACG).

METHODS

Retrospective cohort study. Forty patients (44 eyes) diagnosed with NACG who underwent TS, DS, and FS were included. All eyes in the TS group and seven (47%) eyes in the DS group also underwent goniosynechialysis during the surgery. The main outcome measures (intraocular pressure [IOP], best-corrected visual acuity, complications, and second surgeries) were recorded at the early- (within 1 week) and late-stage (>3 months) follow-up.

RESULTS

The late-stage IOP was significantly lower in the TS (mean ± standard deviation: 13.29 ± 2.49 mm Hg) than in the DS (19.69 ± 6.97 mm Hg) and FS groups (27.57 ± 12.26 mm Hg, p < 0.001). More visual improvements were observed in the TS and DS groups than in the FS group at late-stage follow-up (p = 0.04). The complication rates in the TS, DS, and FS groups were 26%, 33%, and 70%, respectively (p = 0.046); the second surgery rates were 0%, 33%, and 60%, respectively (p < 0.001). In total, one, three, and six severe complications were observed in the TS, DS, and FS groups, respectively. The mean follow-up durations in the TS, DS, and FS groups were 18.89, 20.02, and 25.75 months, respectively.

CONCLUSIONS

NACG management remains challenging. TS presented relatively good clinical efficacy and safety with better postoperative IOP outcomes, lower complications, and second surgery rates among the three groups in eyes with NACG.

Topiramate-Induced Aqueous Misdirection in a Nanophthalmic Eye

A 51-year-old female was referred to the emergency department with a one-day history of severe right eye pain, blurry vision, and conjunctival injection. A review of past ocular history was notable for nanophthalmos and narrow angles with patent peripheral iridotomies. Anterior segment exam findings were consistent with aqueous misdirection and a review of medications indicated recent topiramate initiation for headaches and depression. The acute attack was initially controlled with medical management and plans for future surgical intervention were made. Although ocular screening prior to initiation of topiramate is not recommended, this case highlights the importance of pre-screening in a patient with a pre-existing condition such as nanophthalmos. Additionally, this case addresses the ocular side effects of anti-depressants and the emerging relationship between glaucoma and depression. Appropriately addressing these issues and coordinating care with behavioral health providers has the potential to prevent optic nerve damage and loss of vision.

Effect of Combined Surgery in Patients with Complex Nanophthalmos

(1) Background: To evaluate the efficacy and safety of combined surgery (limited pars plana vitrectomy, anterior-chamber stabilized phacoemulsification, IOL implantation and posterior capsulotomy, LPPV + ACSP + IOL + PC) in complex nanophthalmos. (2) Methods: Patients with complex nanophthalmos were recruited to undergo LPPV + ACSP + IOL + PC from January 2017 to February 2021. Preoperative and post-operative intraocular pressure (IOP), best corrected visual acuity (BCVA), anterior chamber depth (ACD), and number of glaucoma medications were compared using the paired t-test or Wilcoxon signed rank sum tests. Surgical success rate was evaluated. Surgery-associated complications were documented. (3) Results: Forty-five eyes of 37 patients with complex nanophthalmos were enrolled. The mean follow-up period was 21.7 ± 10.6 months after surgery. Mean IOP decreased from 32.7 ± 8.7 mmHg before surgery to 16.9 ± 4.5 mmHg (p < 0.001) at the final follow-up visit, mean logMAR BCVA improved from 1.28 ± 0.64 to 0.96 ± 0.44 (p < 0.001), mean ACD significantly increased from 1.14 ± 0.51 mm to 3.07 ± 0.66 mm (p < 0.001), and the median number of glaucoma medications dropped from 3 (1, 4) to 2 (0, 4) (p < 0.001). The success rate was 88.9% (40 eyes) at the final follow-up visit. Two eyes had localized choroidal detachments which resolved with medical treatment. (4) Conclusions: LPPV + ACSP + IOL + PC is a safe and effective surgical procedure, which can decrease IOP, improve BCVA, deepen the anterior chamber, and reduce the number of glaucoma medications in patients with complex nanophthalmos. It can be considered as one of the first treatment in nanophthalmic eyes with complex conditions.

Treatment of Nanophthalmos Cataracts: Surgery and Complications

PURPOSE

Cataract surgery in patients with nanophthalmos is complicated for ophthalmologists to perform. Due to the unique ocular anatomy, there is a high incidence of complex complications such as angle-closure glaucoma, fluid misdirection syndrome, and uveal effusion syndrome (UES) in the perioperative period of cataract surgery. This article will discuss the management options for cataract surgery in nanophthalmic eyes and complications.

METHODS

This review is searched through PubMed, focusing on articles published in the past 20 years. Articles were reviewed on the anatomical structure of nanophthalmic cataracts, the pathogenesis of complications, the selection of intraocular lenses, and surgical methods.

CONCLUSION

There is a strong correlation between abnormal ocular anatomy and complications in patients with nanophthalmos. Clinicians must not only select the appropriate intraocular lens formula based on the depth of the anterior chamber but also formulate personalized surgical methods based on its unique anatomical structure to avoid complications.

A report on a series of nanophthalmos with histopathology and immunohistochemistry analyses using light microscopy

We aimed to study the histopathological and immunohistochemistry features in clinically diagnosed cases of nanophthalmos using light microscopy. This was an observational comparative study. We enrolled four eyes of four consecutive patients with nanophthalmos and visually significant cataract, who underwent cataract surgery with prophylactic posterior sclerostomy. Histological analysis of the excised scleral tissue was done and compared with age-matched cadaver controls between January 2021 and October 2021. Hematoxylin and Eosin (H&E) stains were used for histological analysis, and was further supplemented with immunohistochemistry (IHC) and immunofluorescence (IF) analyses using a simple light microscope. The immunostained sections were analyzed using confocal microscope for the fibronectin expression level. The main outcome measure was demonstration of histological changes of sclera in nanophthalmic eyes undergoing cataract surgery. Light microscopic features of nanophthalmos revealed thick fibers with fraying and lightly stained cores, irregular serrated edges, and randomly interspersed fibroblasts compared to regular arrangement of collagen fibers seen in cadaver controls. Immunohistochemistry analysis with anti-fibronectin antibody showed strong positivity in clustered fibers in nanophthalmos, and less intense diffuse staining in cadaver tissue. Histoclinical correlation was observed in one nanophthalmic scleral tissue with axial length less than 17 mm showing severe disorganization with diffuse collagenization, loss of fibrillary architecture compared to another specimen with axial length more than 17 mm. Simple, cost-effective light microscopy using basic stains was effective in identifying the characteristic histopathological features in nanophthalmic eyes, and this was further highlighted by immunohistochemistry and immunofluorescence analyses.

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.

Prevalence of complications in eyes with nanophthalmos or microphthalmos: protocol for a systematic review and meta-analysis

INTRODUCTION

Microphthalmos and nanophthalmos are uncommon ocular conditions, whereby affected eyes have smaller dimensions compared to the normal population. Microphthalmos and nanophthalmos present several challenges to ophthalmologists; they have spontaneous and post-operative sequelae such as high hyperopia, angle-closure glaucoma, uveal effusion syndrome, and retinal detachment. This systematic review and meta-analysis intends to assess the prevalence of both the spontaneous complications associated with nanophthalmos and microphthalmos, as well as the post-surgical complications associated with nanophthalmos or microphthalmos.

METHODS AND ANALYSIS

Articles will be searched for, on four online databases: PubMed, EMBASE, Scopus, and Web of Science. Two independent reviewers will identify the studies according to prespecified inclusion and exclusion criteria. All studies included with participants diagnosed with microphthalmos or nanophthalmos in one or both eyes, will be included if they have (i) more than 4 cases and (ii) defined microphthalmos/nanophthalmos as an axial length of < 21 mm or a high lens/eye volume ratio. Nanophthalmos may have an additional diagnostic criterion of posterior wall thickness greater than 1.7 mm. The prevalence of the following complications will be assessed: high hyperopia (spherical equivalent >3D), angle closure glaucoma, uveal effusion syndrome, retinal detachment, and chorioretinal folds. Studies that will be excluded are those that have not adequately defined the criteria for the diagnosis of nanophthalmos or microphthalmos, those studies that have less than five cases, studies with criteria not defined above, and deemed unsuitable, and studies in languages other than English with no published translation. Relevant data will be extracted and assessed for the risk of bias in each article using a modified Joanna Briggs Institute (JBI) assessment tool. The data will then be pooled to determine the prevalence of complications among patients with microphthalmos and nanophthalmos. If the data allows, subgroup analysis will be carried out according to axial length as well as subtype of microphthalmos/nanophthalmos (simple, complex, relative anterior, and posterior).

DISCUSSION

Although nanophthalmos is an uncommon condition that affects the eye, its management and complications can be sight-threatening. Thus, it is important to counsel patients and their families correctly (in the case of children) upon diagnosis and prior to any surgical intervention. This can only be done if the overall prevalence of complications is known.

REGISTRATION

PROSPERO CRD42021227847.

Cataract Surgery in Short Eyes, Including Nanophthalmos: Visual Outcomes, Complications and Refractive Results

Background

To report the visual outcomes, complications and refractive results of phacoemulsification surgery and intraocular lens implantation in a large series of adult patients with short and nanophthalmic eyes.

Methods

The records of all patients with axial length <21.0 mm undergoing phacoemulsification with intraocular lens implantation at an adult teaching hospital were retrospectively reviewed. The main outcome measures were corrected distance visual acuity and refraction at 90 days after surgery and intra- and postoperative complications occurring during the follow-up period.

Results

A total of 71 eyes of 51 patients (median age 71 years, interquartile range 62–75.5) were included. Surgery resulted in an improvement in corrected distance visual acuity in 53 eyes (74.6%) (95% confidence interval, logMAR 0.11–0.29) and was logMAR 0.30 or better in 47 eyes (66.2%). Worsening of corrected distance visual acuity occurred in 9 eyes (12.7%). Median postoperative refractive error was −0.75 dioptres. SRK/T and Kane formula were more accurate in predicting postoperative refraction than Barrett Universal II and Hoffer Q when based on mean absolute error (P < 0.005). Complications occurred in 18 eyes (25.4%). The most frequent complications were iris prolapse, Descemet’s membrane and/or endothelial trauma, transient severe corneal edema and cystoid macular edema. There was no statistically significant difference in complication rates between senior surgeons and senior trainees (P = 0.66).

Conclusion

Cataract surgery in short and nanophthalmic eyes is challenging with a higher complication rate than routine cataract surgery, but frequently results in good visual outcomes. Postoperative refractive outcomes are more difficult to predict in this cohort.

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.

Nanophthalmos-Associated MYRF Gene Mutation Causes Ciliary Zonule Defects in Mice

Purpose

Patients with nanophthalmos who undergo intraocular surgery often present with abnormal ciliary zonules. In a previous study, we reported mutation in MYRF that is implicated in the pathogenesis of nanophthalmos. The aim of this study was to model the mutation in mice to explore the role of MYRF on zonule structure and its major molecular composition, including FBN1 and FBN2.

Methods

Human MYRF nanophthalmos frameshift mutation was generated in mouse using the CRISPR-Cas9 system. PCR and Sanger sequencing were used for genotype analysis of the mice model. Anterior chamber depth (ACD) was measured using hematoxylin and eosin–stained histology samples. Morphologic analysis of ciliary zonules was carried out using silver staining and immunofluorescence. Transcript and protein expression levels of MYRF, FBN1, and FBN2 in ciliary bodies were quantified using quantitative real-time PCR (qRT-PCR) and Western blot.

Results

A nanophthalmos frameshift mutation (c.789delC, p.N264fs) of MYRF in mice showed ocular phenotypes similar to those reported in patients with nanophthalmos. ACD was reduced in MYRF mutant mice (MYRF^mut/+) compared with that in littermate control mice (MYRF^+/+). In addition, the morphology of ciliary zonules showed reduced zonular fiber density and detectable structural dehiscence of zonular fibers. Furthermore, qRT-PCR analysis and Western blot showed a significant decrease in mRNA expression levels of MYRF, FBN1, and FBN2 in MYRF^mut/+ mice.

Conclusions

Changes in the structure and major molecular composition of ciliary zonules accompanied with shallowing anterior chamber were detected in MYRF^mut/+ mice. Therefore, MYRF mutant mice strain is a useful model for exploring pathogenesis of zonulopathy, which is almost elusive for basic researches due to lack of appropriate animal models.

Goniosynechialysis combined with multiple surgeries for secondary glaucoma in nanophthalmos: A case report

BACKGROUND

Management of secondary glaucoma in nanophthalmos has always been challenging, especially for patients with extremely short axial length and extensive angle synechia. This case report discusses a nanophthalmic patient with secondary glaucoma and extensive angle synechia.

CASE PRESENTATION

A 60-year-old woman was referred to our hospital with uncontrolled intraocular pressure (IOP) in her left eye (LE). Slitlamp examination revealed small cornea and shallow anterior chamber (AC) in both eyes. Extensive angle synechia was seen on gonioscopy, and the IOP and axial length were 36 mmHg/15.79 mm in the left eye. She was diagnosed with nanophthalmos and secondary angle-closure glaucoma LE. Laser peripheral iridectomy (LPI) was performed, but the IOP LE remained elevated and uncontrolled on brinzolamide and brimonidine. The IOP LE was then normalized with the application of 2% pilocarpine. During the follow-up period, the AC of the LE showed progressive shallowing, and 5 months post LPI the IOP became uncontrollable. Goniosynechialysis combined with phacoemulsification, lamellar sclerectomy, sclerostomy, peripheral iridectomy, capsulotomy, and anterior vitrectomy were performed LE. Immediately after surgery, the AC deepened and the IOP stabilized. However, the IOP rose again post-surgically at 1 week and again at 2 months. A generally shallow AC and obstructed capsule hole were present. YAG laser capsulotomy was performed, and the IOP normalized and the AC deepened. Eighteen months after surgery, the IOP LE was 12 mmHg and the AC remained stable.

CONCLUSION

Goniosynechialysis combined with multiple surgical procedures could be considered an alternative treatment regimen for nanophthalmos patients with secondary glaucoma and extensive angle synechia.

The role of primary needle revision after Ahmed glaucoma valve (AGV) implantation

PURPOSE

To evaluate the efficacy and safety of primary needle revision after Ahmed Glaucoma Valve (AGV) implantation in comparison with glaucoma medication use.

METHODS

In this interventional case series, 23 eyes of 23 patients who underwent AGV implantation were enrolled. Needle revision was performed when the intraocular pressure was higher than the target pressure before glaucoma medications. Using a 30-gauge needle, the Tenon's capsule over the plate was incised and the bleb was reformed. Patients were examined on a postoperative day one, weekly (for four weeks), and every 1-3 months. Two criteria were used to define cumulative success as a minimum 20% reduction in IOP and 5 < IOP ≤ 21 mmHg (Criteria A) or 5 < IOP ≤ 18 mmHg (Criteria B) without (Complete success) or with (Qualified success) glaucoma medication.

RESULTS

In this pilot study, we enrolled 23 patients with a mean age of 53.8 ± 12.4 years (25-78 years) who underwent AGV implantation and a one-year follow-up period. The mean number of primary needle revision was 2.2 ± 1.6 (1-6). One year postoperatively, the cumulative success rate was 91.4% and 86.9% based on Criteria A and B, respectively. The average of preoperative IOP was 28.26 ± 8.86 mmHg (range 15-46 mmHg), reaching 13.78 ± 3.54 mmHg (range 8-20) at the end of the one-year follow-up. (P < 0.001) The mean preoperative medication significantly decreased from a median of 4 (range 3-4) at baseline to 2 (range 1-4) after the one-year follow-up (P < 0.001). One patient experienced leakage over the plate, which was successfully treated via conservative management.

CONCLUSION

This pilot study showed that primary needle revision is a safe and effective method for controlling IOP after AGV implantation with a lower need for medication.

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.

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.

Radius-Maumenee syndrome: Beyond a diagnostic and therapeutic challenge

Radius-Maumenee syndrome (SRM) or idiopathic episcleral venous hypertension (HVEI) is an uncommon disorder that occurs with a dilation of the episcleral vessels and an increase in intraocular pressure (IOP). It is a syndrome that constitutes a diagnostic and therapeutic challenge for the ophthalmologist. A case is presented in which, despite making an early diagnosis and trying to plan a treatment aimed at avoiding choroidal effusion, its appearance was unavoidable, having to treat it twice with good functional results so far.

Transscleral cyclophotocoagulation as primary management in a nanophthalmic eye with anterior uveitis and secondary mixed mechanism glaucoma

A 36-year-old woman presented with eye pain and blurring of vision in her right eye. On eye examination, it was noted that there were angle-closure glaucoma and anterior uveitis in both eyes. Ocular ultrasound showed short axial lengths as well as a choroidal thickening in both eyes, confirming the diagnosis of nanophthalmos. Nanophthalmos is a condition where the eye is abnormally short, resulting in axial hyperopia and predisposing it to angle-closure glaucoma. The patient was initially managed medically, but the glaucoma was intractable. The patient underwent repeated sessions of transscleral cyclophotocoagulation which eventually lowered the intraocular pressure. The management of nanophthalmic eyes can be quite challenging due to the risk of inciting uveal effusion syndrome with any form of intraocular surgery. Controlled and repeated sessions of transscleral cyclophotocoagulation may be considered as a viable management option in these cases.

[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.

Choroidal detachments: what do optometrists need to know?

Choroidal detachments occur when there is an accumulation of fluid or blood in the suprachoroidal space, a potential space situated between the choroid and the sclera. They are an uncommon ocular pathology. The most common cause of choroidal detachment is secondary to trabeculectomy; however, there are other causes such as trauma and inflammation. Clinically, choroidal detachments may vary in presentation from asymptomatic, to very poor vision, severe ocular pain, vomiting and nausea. Ocular findings associated with choroidal detachments include serous retinal detachment, secondary angle closure, and a very shallow anterior chamber. Optometrists, as primary eye care providers, need to be aware of the clinical signs and symptoms associated with choroidal detachments and ensure that appropriate and timely management, with a referral to an ophthalmologist, is instigated for optimal visual outcomes. In this review, the pathophysiology, detection, and associated risk factors for choroidal detachments are discussed, and evidence-based management recommendations in an optometric context are provided. The characteristics and management of uveal effusion syndrome are also reviewed, as this can cause idiopathic exudative choroidal detachments distinct from classical choroidal detachment.

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.

Spectrum of Angle Closure, Uveal Effusion Syndrome, and Nanophthalmos

Nanophthalmos, uveal effusion syndrome, and acute angle closure glaucoma (ACG) can present as a continuum in a patient, as is described here. This patient's angle closure was thought to be caused by idiopathic uveal effusion syndrome, and while there are no generally accepted diagnosis criteria for nanophthalmos, our patient fulfilled the criteria as defined by Wu.¹⁰ To prevent development of further angle closure, the decision was made to do cataract extraction as opposed to medical management.

Surgical outcomes of 23-gauge transconjunctival pars plana vitrectomy combined with lensectomy for glaucomatous eyes with extremely shallow anterior chamber and cataract

Background

Glaucoma combined with an extremely shallow anterior chamber and cataracts remains as a complex condition to deal with. And the emergence of microincision vitrectomy surgery (MIVS) system may provide an ideal option for the treatment of that. We report a clinical study of surgical outcomes of 23-gauge transconjunctival pars plana vitrectomy (PPV) combined with lensectomy in the treatment of glaucomatous eyes with extremely shallow anterior chamber and cataract.

Methods

Prospective, nonrandomized and noncomparative case series study. Consecutive patients with secondary glaucoma, extremely shallow anterior chamber and cataract were recruited to have combined surgeries of 23-gauge transconjunctival pars plana vitrectomy and lensectomy. The main outcomes were best corrected visual acuity (BCVA), intraocular pressure (IOP), anterior chamber depth (ACD), number of anti-glaucoma medications and surgery-associated complications.

Results

Seventeen consecutive patients with secondary glaucoma, extremely shallow anterior chamber and cataract were recruited. The mean follow-up was 21.2 ± 8.8 months. Postoperatively, there was no significant improvement of BCVA (P = 0.25). The mean intraocular (IOP) decreased significantly from 43.14 ± 6.53 mmHg to 17.29 ± 1.80 mmHg (P < 0.001), and the mean depth of anterior chamber increased significantly from 0.507 ± 0.212 mm to 3.080 ± 0.313 mm (P < 0.001). The mean number of anti-glaucoma medications decreased from 4.1 ± 0.8 to 0.6 ± 0.8 (P < 0.001). No severe vision-threatening intra- or post-operative complications occurred.

Conclusions

Glaucoma with an extremely shallow anterior chamber and cataract can be managed well with the combined surgeries of 23-gauge pars plana vitrectomy and lensectomy. The surgical procedure is an effective and safe method to resolve the pupillary block and deepen the anterior chamber.

Surgical management of glaucoma secondary to idiopathic elevated episcleral venous pressure

Idiopathic elevated episcleral venous pressure is characterized by dilated episcleral veins and open angle glaucoma. Trabeculectomies in these eyes are often complicated by uveal effusions (intraoperative or postoperative) at nonhypotonous pressures. We highlight the ability to avoid the need for sclerostomies by preventing intraoperative shallowing of the anterior chamber and the use of tight scleral sutures which should be adjusted postsurgery to gradually reach the target intraocular pressure in a step-wise manner.

Cataract surgery in patients with nanophthalmos: results and complications

PURPOSE

To evaluate phacoemulsification surgery results and complications in patients with nanophthalmos.

METHODS

The records of 9 patients with nanophthalmos who had cataract surgery from January 2011 through January 2015 were retrospectively reviewed. Nanophthalmos was diagnosed by the presence of an eye with an axial length (AL) less than 20.5 mm. The records were reviewed for ocular diagnosis, keratometry, anterior chamber depth (ACD), AL, ocular surgeries, visual acuity, and complications.

RESULTS

A total of 14 eyes of 9 patients (8 women, 1 man) with a mean age of 72 years (range 48-86) were reviewed. Mean AL was 18.72 mm and mean ACD was 2.30 mm. Mean preoperative spherical equivalent (+8.55 ± 6.44 diopters (D)) was reduced to +0.30 ± 2.17 D at last follow-up visit. Mean best-corrected visual acuity (BCVA) was +0.68 ± 0.55 logarithm of the minimum angle of resolution (logMAR) preoperatively and improved to +0.55 ± 0.73 logMAR at last follow-up visit. Visual acuity remained stable or improved in 11 eyes. Five eyes did not achieve final BCVA ≥+0.3 logMAR. Complications occurred in 3 eyes (21.4%) and included 1 case of posterior capsule rupture, 1 case of severe iritis and rhegmatogenous retinal detachment 2 weeks postoperatively, and 1 other case of iritis. No postoperative uveal effusion was seen.

CONCLUSIONS

Although phacoemulsification seems to be relatively safe in nanophthalmic eyes, surgeons need to be aware of the challenges of this procedure in these high-risk eyes. Nevertheless, with careful preoperative evaluation and planning, most cases were uncomplicated and resulted in improvement of BCVA.

Isolated posterior uveal effusion: expanding the spectrum of the uveal effusion syndrome

Uveal effusion syndrome usually causes peripheral chorioretinal detachment, but posterior effusion may present as isolated macular edema with serous macular detachment in the setting of hyperopia and a thickened posterior choroid. Carbonic anhydrase inhibitors may be effective to treat this condition.

Challenges in the implantation of a Boston type 1 keratoprosthesis and a glaucoma drainage device in a nanophthalmic eye

A 67-year-old man presented with hand motions vision, a decompensated vascularised cornea and a flat anterior chamber in the right eye 5 years following cataract and glaucoma surgery. He lost the left eye several years ago following a similar intervention. The intraocular pressure (IOP) was 19 mm Hg on four antiglaucoma medications and the axial length was 19 mm. In view of the high risk for graft failure, a Boston type 1 keratoprosthesis (Kpro) was planned for visual rehabilitation, and a glaucoma drainage device (GDD) for IOP control. Although a combined GDD with Kpro was indicated, we performed sequential surgeries to avoid vision threatening hypotony-related complications. He underwent parsplana vitrectomy, prophylactic lamellar sclerectomies and Kpro at the first stage, followed by a paediatric Ahmed glaucoma valve implantation 3 months later. Despite precautions, postoperative uveal effusion occurred but could be managed conservatively. His IOP was controlled; visual acuity improved to 20/50 and remained stable at 2 years.

A case of 25 gauge vitrectomy for malignant glaucoma with microphthalmos

We report the first case report of pars plana lensectomy (PPL) and pars plana vitrectomy using a 25 gauge vitrectomy system for microphthalmos.

Assessment of the anterior chamber angle in patients with nanophthalmos: an anterior segment optical coherence tomography study

PURPOSE

To quantitatively assess the parameters of anterior chamber and angle dimensions by anterior segment optical coherence tomography (AS-OCT) in nanophthalmos.

METHODS

In this prospective, cross-sectional and comparative study, 34 eyes of 34 healthy individuals (control group) and 37 eyes of 37 patients with nanophthalmos (study group) were enrolled. A single experienced ophthalmologist imaged and measured the right eye with the Visante AS-OCT. The anterior chamber angle (ACA), angle opening distance (AOD) at 500 and 750 µm from the scleral spur, and trabecular-iris space area (TISA) at 500 and 750 µm at the nasal and temporal angles were measured.

RESULTS

Mean nasal/temporal ACA was 44.90 ± 9.09/47.07 ± 8.69° in the control group and 32.15 ± 10.30/29.77 ± 10.57° in the study group (p < 0.001). Mean nasal/temporal AOD500 and AOD750 was 0.52 ± 0.18/0.53 ± 0.15 mm and 0.71 ± 0.26/0.71 ± 0.23 mm in the control group. The mean nasal/temporal AOD500 and AOD750 were 0.33 ± 0.12/0.31 ± 0.15 mm and 0.48 ± 0.16/0.47 ± 0.22 mm in the study group. Mean nasal/temporal TISA500 and TISA750 were 0.16 ± 0.06/0.17 ± 0.05 mm(2) and 0.31 ± 0.11/0.33 ± 0.09 mm(2) in the control group. Mean nasal/temporal TISA500 and TISA750 were 0.11 ± 0.04/0.09 ± 0.05 mm(2) and 0.20 ± 0.07/0.20 ± 0.10 mm(2) in the study group. All values were significantly lower in the study group compared with the control group.

CONCLUSION

Determination of angle parameters using AS-OCT is a rapid noncontact method that is useful in patients with nanophthalmos. The findings demonstrated that nanophthalmic eyes had lower ACA parameters including ACA, AOD500, AOD750, TISA500 and TISA750 at the nasal and temporal angles.

Isolated microcornea: case report and relation to other "small eye" phenotypes

Isolated microcornea is a very rarely-described condition of reduced cornea size (less than 11 mm horizontal diameter) in an individual without other significant ocular (or systemic) findings. This case report describes the biometric features of a boy with isolated microcornea (the youngest and most completely described patient to the best of our knowledge) and suggests that the condition is the same entity as relative anterior microphthalmos.

Unusual rapid resolution of posttrabeculectomy exudative retinal detachment with only topical corticosteroid therapy in a case of nanopthalmos

PURPOSE

The purpose of this study was to report a case of nanophthalmos with unusual rapid resolution of exudative retinal detachment, which had developed the fifth day after filtering surgery with only topical corticosteroid therapy.

METHODS

Five days after an uncomplicated trabeculectomy for the management of glaucoma, the patient developed exudative retinal detachment.

RESULTS

Without choroidal drainage and any other treatment, exudative retinal detachment started resolving in 2 days and disappeared in 2 weeks under only topical corticosteroid therapy.

CONCLUSION

Topical corticoid therapy alone may be sufficient to achieve quick resolution of exudative retinal detachment secondary to glaucoma surgery in nanophthalmic eyes.

Autosomal-recessive posterior microphthalmos is caused by mutations in PRSS56, a gene encoding a trypsin-like serine protease

Posterior microphthalmos (MCOP) is a rare isolated developmental anomaly of the eye characterized by extreme hyperopia due to short axial length. The population of the Faroe Islands shows a high prevalence of an autosomal-recessive form (arMCOP) of the disease. Based on published linkage data, we refined the position of the disease locus (MCOP6) in an interval of 250 kb in chromosome 2q37.1 in two large Faroese families. We detected three different mutations in PRSS56. Patients of the Faroese families were either homozygous for c.926G>C (p.Trp309Ser) or compound heterozygous for c.926G>C and c.526C>G (p.Arg176Gly), whereas a homozygous 1 bp duplication (c.1066dupC) was identified in five patients with arMCOP from a consanguineous Tunisian family. In one patient with MCOP from the Faroe Islands and in another one from Turkey, no PRSS56 mutation was detected, suggesting nonallelic heterogeneity of the trait. Using RT-PCR, PRSS56 transcripts were detected in samples derived from the human adult retina, cornea, sclera, and optic nerve. The expression of the mouse ortholog could be first detected in the eye at E17 and was maintained into adulthood. The predicted PRSS56 protein is a 603 amino acid long secreted trypsin-like serine peptidase. The c.1066dupC is likely to result in a functional null allele, whereas the two point mutations predict the replacement of evolutionary conserved and functionally important residues. Molecular modeling of the p.Trp309Ser mutant suggests that both the affinity and reactivity of the enzyme toward in vivo protein substrates are likely to be substantially reduced.

Glaucoma: genes, phenotypes, and new directions for therapy

Glaucoma, a leading cause of blindness worldwide, is characterized by progressive optic nerve damage, usually associated with intraocular pressure. Although the clinical progression of the disease is well defined, the molecular events responsible for glaucoma are currently poorly understood and current therapeutic strategies are not curative. This review summarizes the human genetics and genomic approaches that have shed light on the complex inheritance of glaucoma genes and the potential for gene-based and cellular therapies that this research makes possible.