Couching of cataractous lens in microphthalmic eyes with irido-fundal coloboma: revisiting the historical technique.

PURPOSE: Cataract surgery in microphthalmic eyes is challenging due to anatomical restraints, hard bulky nucleus. This series aims to evaluate the safety and efficacy of couching of intraocular lens in irido-fundal coloboma with microphthalmos. SETTING: Tertiary care centre in South India. DESIGN: Retrospective non-comparative study in eyes with irido-fundal coloboma, corneal diameter < 7 mm and brown cataract. Visual acuity less than 6/60 in other eye. METHODS: Anterior chamber entry made, zonules broken and lens dislocated into the vitreous cavity in a controlled manner. Baseline Clinico-demographic details, corrected distance visual acuity (CDVA), Intra-ocular pressure (IOP), corneal diameter, axial length, lens status and post-surgery CDVA, IOP and complications recorded and followed up for atleast 6 months. RESULTS: Fifteen eyes of 15 subjects were evaluated with a mean age 49.4 ± 10.9 years. At baseline, mean IOP 14.5 ± 3.8 mmHg, mean axial length 19.3 ± 0.5 mm, mean corneal diameter was 6.5 ± 0.34 mm and CDVA 2 logMAR which improved to 1.5 logMAR at 3 months (p value 0.002). Transient spike in IOP in 33.3% subjects was medically managed with no significant difference in IOP (p > 0.05) at baseline (14.5 ± 3.8 mmHg), 3 months post-surgery (16 ± 2.8 mmHg) and 6 months post-surgery (14.9 ± 2.5 mmHg). One patient underwent re-couching. No other major complications were noted. CONCLUSION: Couching of cataractous lens is an effective and safe method in microphthalmic eyes with irido-fundal coloboma as last resort procedure, where no other surgical procedure may work. It provides an ambulatory gain of visual acuity in previously non-ambulatory subjects. Corneal measurements help in determining the subset of patients where couching offers viable option.

Development of a potent embryonic chick lens model for studying congenital cataracts in vivo.

Congenital cataracts are associated with gene mutations, yet the underlying mechanism remains largely unknown. Here we reported an embryonic chick lens model that closely recapitulates the process of cataract formation. We adopted dominant-negative site mutations that cause congenital cataracts, connexin, Cx50E48K, aquaporin 0, AQP0R33C, αA-crystallin, CRYAA R12C and R54C. The recombinant retroviruses containing these mutants were microinjected into the occlusive lumen of chick lenses at early embryonic development. Cx50E48K expression developed cataracts associated with disorganized nuclei and enlarged extracellular spaces. Expression of AQP0R33C resulted in cortical cataracts, enlarged extracellular spaces and distorted fiber cell organization. αA crystallin mutations distorted lens light transmission and increased crystalline protein aggregation. Together, retroviral expression of congenital mutant genes in embryonic chick lenses closely mimics characteristics of human congenital cataracts. This model will provide an effective, reliable in vivo system to investigate the development and underlying mechanism of cataracts and other genetic diseases.

Atypical presentation of peripheral posterior lenticonus and role of multi-modal ocular imaging in its diagnosis and management.

A 6-year-old systemically healthy child presented with visual acuity of 1/60, N18 oculusdextrus (OD), and 6/18, N6 oculus sinister (OS). Slit-lamp biomicroscopy revealed suspicious bilateral inferotemporal pigmented ciliary body (CB) tumour, protruding posterior capsule and temporal posterior subcapsular cataract oculus uterque. Anterior segment optical coherence tomography, ultrasonography, ultrasonic biomicroscopy and Scheimpflug imaging revealed protruding posterior capsule and cortex abutting but not arising from CB suggestive of peripheral pigmented posterior lenticonus with hypermetropia (axial length 20.27 mm OD and 19.97 mm OS). Aberrometry revealed high internal aberrations and low Dysfunctional Lens Index (DLI). Lens aspiration with intraocular lens implantation in the bag OD and contact lens correction OS were undertaken. The child had a postoperative visual gain of 3/60, N18 with improved aberrometric profile OD, and was advised amblyopia therapy. Rarely posterior lenticonus can mimic a CB mass. Multi-modal ocular imaging can aid in its diagnosis and management. DLI may serve as a useful indicator of surgery in such cases.

Alport syndrome with bilateral simultaneous anterior and posterior lenticonus with severe temporal macular thinning.

Alport syndrome (AS) is a hereditary disease with various modes of inheritance, X-linked being the the most common. Anterior lenticonus is the characteristic abnormality along with perimacular and peripheral fleck retinopathy. Our two cases of AS had simultaneous anterior and posterior lenticonus with severe temporal macular thinning on optical coherence tomography with no specific renal symptomatology and were diagnosed as AS without any invasive renal biopsy. First patient was a 19-year-old man who presented with compound myopia due to bilateral anterior and posterior lenticonus with perimacular fleck retinopathy and lozenge sign and bilateral moderate sensorineural hearing loss (SNHL). Second patient was a 24-year-old man who presented with difficulty in vision due to bilateral anterior and posterior lenticonus with bilateral severe SNHL. Our cases emphasise the crucial role of an ophthalmologist in diagnosing AS before the onset of renal symptoms and prompting further nephrological work-up in the patient or the carrier.

Influence of the vitreolenticular interface in pediatric cataract surgery.

PURPOSE: To report the status of Berger space in pediatric cataract cases and the influence of anterior vitreolenticular interface dysgenesis during primary posterior continuous curvilinear capsulorhexis (PCCC). SETTING: Department of Ophthalmology, Antwerp University Hospital, Edegem, Belgium. DESIGN: Prospective case series. METHODS: The study comprised consecutive pediatric cataract cases planned for bag-in-the-lens intraocular lens (BIL IOL) implantation. A video-based analysis of the surgical interventions included the type of crystalline lens opacification, presence of a posterior capsule plaque (PCP), presence of anterior vitreolenticular interface dysgenesis, complications during primary PCCC, integrity of the anterior hyaloid membrane, need for anterior vitrectomy, and feasibility of BIL IOL implantation. RESULTS: Abnormalities in Berger space were observed in 35 of the 64 pediatric cataract cases. Anterior vitreolenticular interface dysgenesis was most often found in cases with persistent fetal vasculature (PFV) and those with posterior cataract. Anterior vitreolenticular interface dysgenesis was diagnosed significantly more often in eyes with unilateral cataract and those with PCP. In pediatric cataract cases presenting with PCP and anterior vitreolenticular interface dysgenesis, the primary PCCC procedure was surgically more demanding, often resulting in detectable breaks in the anterior hyaloid membrane (58.6%) and sometimes necessitating an unplanned anterior vitrectomy (13.8%). Bag-in-the-lens IOL implantation was feasible in all except 1 eye with PFV, which was left aphakic. CONCLUSIONS: Primary vitreolenticular interface abnormalities are often encountered during pediatric cataract surgeries, especially when confronted with PCP in a unilateral cataract. The presence of anterior vitreolenticular interface dysgenesis may complicate a primary PCCC procedure, resulting in an unplanned anterior vitrectomy in some cases.

Clinical spectrum and surgical outcomes in spherophakia: a prospective interventional study.

PurposeTo study the varied clinical presentations of patients with spherophakia, their management using surgical methods, and the clinical outcomes.Patients and methodsA prospective interventional study of 13 patients of spherophakia who presented to us from January 2014 and were followed up over the course of their treatment, and the data were documented for analysis.ResultsIn all, 26 eyes of 13 patients were reviewed and the median age of presentation was 12±12.05 years. All patients had a bilateral presentation with 22 eyes having lenticular myopia with a mean refractive error of -11.5±12.945 DS. Ten eyes presented with glaucoma of which six had raised intraocular pressure (IOP) >21 mm Hg. A total of 23 eyes underwent lens extraction for dislocation/subluxation. Lens extraction helped lower overall IOP. Refractive rehabilitation was done with ACIOL, posterior chamber intraocular lens (PCIOL) with capsular tension ring, and scleral-fixated intraocular lens (SFIOL) in respective cases with ACIOLs being the most commonly used option.ConclusionsSpherophakia is a rare condition, which exhibits a varying degree of lenticular myopia, glaucoma, and subluxation of the crystalline lens. Lensectomy with proper rehabilitation using ACIOL, PCIOL, or SFIOL is a method of managing subluxation and unacceptable myopia. Lensectomy may also be a viable option of controlling glaucoma alongside medications and glaucoma surgery for the management of glaucoma in such cases.

Relationship between somatic mosaicism of Pax6 mutation and variable developmental eye abnormalities-an analysis of CRISPR genome-edited mouse embryos.

The clustered regularly interspaced short palindromic repeat (CRISPR)/CRISPR-associated protein (Cas) system is a rapid gene-targeting technology that does not require embryonic stem cells. To demonstrate dosage effects of the Pax6 gene on eye formation, we generated Pax6-deficient mice with the CRISPR/Cas system. Eyes of founder embryos at embryonic day (E) 16.5 were examined and categorized according to macroscopic phenotype as class 1 (small eye with distinct pigmentation), class 2 (pigmentation without eye globes), or class 3 (no pigmentation and no eyes). Histologically, class 1 eyes were abnormally small in size with lens still attached to the cornea at E16.5. Class 2 eyes had no lens and distorted convoluted retinas. Class 3 eyes had only rudimentary optic vesicle-like tissues or histological anophthalmia. Genotyping of neck tissue cells from the founder embryos revealed somatic mosaicism and allelic complexity for Pax6. Relationships between eye phenotype and genotype were developed. The present results demonstrated that development of the lens from the surface ectoderm requires a higher gene dose of Pax6 than development of the retina from the optic vesicle. We further anticipate that mice with somatic mosaicism in a targeted gene generated by CRISPR/Cas-mediated genome editing will give some insights for understanding the complexity in human congenital diseases that occur in mosaic form.

Coexistence of optic pit and coloboma of iris, lens, and choroid: a case report / Coexistência de fosseta óptica e coloboma de íris, cristalino e coroide: um primeiro relato de caso

ABSTRACT A 42-year-old woman was admitted to our clinic with a complaint of glare in both eyes. Biomicroscopic examination of both the eyes revealed iris and lens colobomas in the inferior quadrant. Fundus examination of the right eye revealed an oval and gray inferotemporal optic pit and two choroid colobomas in the inferior quadrant. In the left eye, two choroid colobomas were detected that were inferior to the optic nerve head. Furthermore, a 21-year-old man presented to our clinic for a routine ophthalmologic examination. Bilateral biomicroscopic examination was normal. Fundus examination of the left eye revealed an oval and gray inferotemporal optic pit and a choroid coloboma that was inferior to the optic nerve head. Here we describe optic pits co-occurring with iris, lens, and choroidal colobomas. On the basis of these cases, a defect in the closure of the embryonic fissure is the most plausible etiology of the optic pit.

RESUMO Uma mulher de 42 anos de idade foi internada em nossa clínica com queixa de ofuscamento em ambos os olhos. O exame biomicroscópico revelou coloboma de íris e cristalino no quadrante inferior em ambos os olhos. O exame de fundo do olho direito revelou um fosseta óptica oval e acinzentada na região inferotemporal e dois colobomas coroide no quadrante inferior. No olho esquerdo, dois colobomas de coroide foram detectados inferiormente à da cabeça do nervo óptico. Outro homem de 21 anos apresentou-se em nossa clínica para um exame oftalmológico de rotina. O exame biomicroscópico foi normal, bilateralmente. O exame de fundo do olho esquerdo revelou uma fosseta oval e acinzentada de nervo óptico óptico inferotemporal e um coloboma coroide inferior à cabeça do nervo óptico. Nestes relatos nós descrevemos fossetas ópticas ocorrendo simultaneamente com colobomas de íris, cristalino, e coroide. Com base nestes casos, o defeito no fechamento da fissura embrionária é uma provável etiologia da fosseta óptica.

Indications and clinical outcomes of capsular tension ring implantation in phacoemulsification surgery at a tertiary teaching hospital: A review of 4316 cataract surgeries.

PURPOSE: To reveal the indications, clinical outcomes and complications of capsular tension ring (CTR) implantation in a series of consecutive phacoemulsification surgeries during a three-year interval. METHODS: A review of all patients undergoing cataract surgery with insertion of a CTR between 2010 and 2013 was conducted at our tertiary teaching ophthalmology department. The demographic details of patients, indications and clinical outcomes of CTR implantation were evaluated. RESULTS: Between 2010 and 2013, 4316 phacoemulsification surgeries were performed and of these surgeries CTR implantation was done in 41 eyes of 36 patients. The indications of CTR implantation were zonular dehiscence or weakness associated with mature cataract (29.2%), trauma (24.3%), pseudoexfoliation syndrome (19.5%), retinitis pigmentosa (14.6%), degenerative myopia (9.7%), and lens coloboma (2.4%). Posterior chamber intraocular lens (PCIOL) was implanted into the capsular bag in all eyes. Dislocation of PCIOL was not observed in any case. Transient IOP increased in 5 eyes (12%) and corneal edema in 14 eyes were noted. Posterior capsular opasification in 1 eye (2.4%), anterior capsule phimosis in 1 eye (2.4%) and cystoid macular edema in 1 eye (2.4%) were detected as late complications. CONCLUSION: The frequency of CTR implantation was 0.97% due to our study. In complicated cataract surgeries, CTR implantation seems to improve clinical outcomes.

Posterior tunica vasculosa lentis and "brittle star" of persistent fetal vasculature.

A 17-month-old girl referred for a suspected ciliary body medulloepithelioma was found to have persistent fetal vasculature. Fluorescein angiography showed perfused hyaloid artery posterior tunica vasculosa lentis with brittle star appearance and nonperfused anterior pupillary membrane. Ultrasound biomicroscopy confirmed absence of iris or ciliary body solid tumor.

Aberrant activation of p53 due to loss of MDM2 or MDMX causes early lens dysmorphogenesis.

Although forming a heterodimer or heterooligomer is essential for MDM2 and MDMX to fully control p53 during early embryogenesis, deletion of either MDM2 or MDMX in specific tissues using the loxp-Cre system reveals phenotypic diversity during organ morphogenesis, which can be completely rescued by loss of p53, suggesting the spatiotemporal independence and specificity of the regulation of p53 by MDM2 and MDMX. In this study, we investigated the role of the MDM2-MDMX-p53 pathway in the developing lens that is a relatively independent region integrating cell proliferation, differentiation and apoptosis. Using the mice expressing Cre recombinase specifically in the lens epithelial cells (LECs) beginning at E9.5, we demonstrated that deletion of either MDM2 or MDMX induces apoptosis of LEC and reduces cell proliferation, resulting in lens developmental defect that finally progresses into aphakia. Specifically, the lens defect caused by MDM2 deletion was evident at E10, occurring earlier than that caused by MDMX deletion. These lens defects were completely rescued by loss of two alleles of p53, but not one allele of p53. These results demonstrate that both MDM2 and MDMX are required for monitoring p53 activity during lens development, and they may function independently or synergistically to control p53 and maintain normal lens morphogenesis.

Surgical outcomes of isolated lens coloboma with or without cataract among young adults.

OBJECTIVE: To evaluate the visual and refractive outcomes after phacoemulsification surgery in eyes with isolated lens coloboma. DESIGN: Prospective, consecutive case series. PARTICIPANTS: Eighteen eyes with isolated lens coloboma of 13 patients were included in the study. Mean patient age was 13.9 ± 6.5 years. METHODS: Patients underwent phacoemulsification surgery, with combined implantation of capsular tension ring (CTR) and intraocular lens. In colobomas of less than 120°, a CTR was used, whereas in colobomas of more than 120°, a Cionni-modified single eyelet CTR was used to achieve better capsular centration. The main outcome measures were uncorrected distance visual acuity, corrected distance visual acuity, refraction, and keratometry. RESULTS: Mean logMAR uncorrected distance visual acuity and corrected distance visual acuity improved significantly from 1.53 ± 0.35 and 1.02 ± 0.47 before surgery to 0.67 ± 0.51 and 0.52 ± 0.49 at the last visit of the follow-up (p < 0.001). Mean refractive cylinder and spherical equivalent decreased significantly from -6.73 ± 1.73 and -6.72 ± 4.07 D preoperatively to -1.40 ± 1.39 and -0.83 ± 1.31 D at the end of the follow-up (p = 0.001 and p = 0.01, respectively). Mean keratometric astigmatism at preoperative and postoperative visits were 1.58 ± 0.97 and 1.65 ± 0.94 D, respectively (p = 0.70). CONCLUSIONS: Phacoemulsification with CTR and intraocular lens implantation is an effective and safe option for providing a refractive correction and a significant visual improvement in eyes with isolated lens coloboma.

Cryptic uveitis in a patient with morning glory syndrome.

BACKGROUND: A 71-year-old female presented on 3 occasions with escalating pain in a congenitally blind eye. Examination revealed hypertensive uveitis with morning glory optic disc dysplasia and absence of a crystalline lens. There was no previous intraocular surgery or trauma. Intensive anti-hypertensive agents and topical steroids did not control intraocular pressure (IOP) or inflammation. RESULTS: Dilated fundus examination on the third clinical review revealed a luxated cataractous lens on the retina. Pars plana vitrectomy and fragmatome lensectomy controlled inflammation and IOP, with resolution of ocular pain. DISCUSSION: This is an exceptional case of phacogenic uveitis with secondary glaucoma occurring years after spontaneous crystalline lens luxation in a patient with morning glory syndrome. The embryological pathogenesis of morning glory syndrome and the significance of accelerated cataractogenesis and zonular weakness are discussed. Hypertensive uveitis with unexplained absence of a crystalline lens in a blind eye must prompt suspicion of delayed phacogenic uveitis following asymptomatic lens luxation.

Dramatic regression of persistent tunica vasculosa lentis associated with retinopathy of prematurity following treatment with intravitreal bevacizumab.

The authors describe a preterm infant who developed advanced retinopathy of prematurity bilaterally with a prominent tunica vasculosa lentis. Treatment with intravitreal bevacizumab resulted in regression of the tunica vasculosa lentis and posterior manifestations of the retinopathy of prematurity. RetCam imaging (Clarity Medical Systems, Pleasanton, CA) of the anterior segment was used to document the dramatic tunica vasculosa lentis resolution.

Vitrectorhexis and lens aspiration with posterior chamber intraocular lens implantation in spherophakia.

UNLABELLED: We describe a technique that uses the vitrector to perform successful lens aspiration and posterior chamber intraocular lens (IOL) implantation in children with spherophakia and anterior lens subluxation. After an anterior chamber maintainer is placed, the ocutome is introduced through a limbal incision to perform a circular vitrectorhexis to avoid excessive manipulation of the unstable lens followed by gentle cortex aspiration. A foldable IOL is injected into the sulcus (3-piece IOL) or bag (1-piece IOL) if the capsule is sufficiently stable. Through a pars plana incision, the ocutome is then used to perform a posterior capsulotomy to prevent late posterior capsule opacification. In our patient, sulcus IOL placement was more stable than in-the-bag placement. FINANCIAL DISCLOSURE: Neither author has a financial or proprietary interest in any material or method mentioned.

Loss of Msx2 function down-regulates the FoxE3 expression and results in anterior segment dysgenesis resembling Peters anomaly.

Complex molecular interactions dictate the developmental steps that lead to a mature and functional cornea and lens. Peters anomaly is one subtype of anterior segment dysgenesis especially due to abnormal development of the cornea and lens. MSX2 was recently implicated as a potential gene that is critical for anterior segment development. However, the role of MSX2 within the complex mechanisms of eye development remains elusive. Our present study observed the morphologic changes in conventional Msx2 knockout (KO) mice and found phenotypes consistent with Peters anomaly and microphthalmia seen in humans. The role of Msx2 in cornea and lens development was further investigated using IHC, in situ hybridization, and quantification of proliferative and apoptotic lens cells. Loss of Msx2 down-regulated FoxE3 expression and up-regulated Prox1 and crystallin expression in the lens. The FoxE3 and Prox1 malfunction and precocious Prox1 and crystallin expression contribute to a disturbed lens cell cycle in lens vesicles and eventually to cornea-lentoid adhesions and microphthalmia in Msx2 KO mice. The observed changes in the expression of FoxE3 suggest that Msx2 is an important contributor in controlling transcription of target genes critical for early eye development. These results provide the first direct genetic evidence of the involvement of MSX2 in Peters anomaly and the distinct function of MSX2 in regulating the growth and development of lens vesicles.

Rac1 GTPase-deficient mouse lens exhibits defects in shape, suture formation, fiber cell migration and survival.

Morphogenesis and shape of the ocular lens depend on epithelial cell elongation and differentiation into fiber cells, followed by the symmetric and compact organization of fiber cells within an enclosed extracellular matrix-enriched elastic capsule. The cellular mechanisms orchestrating these different events however, remain obscure. We investigated the role of the Rac1 GTPase in these processes by targeted deletion of expression using the conditional gene knockout (cKO) approach. Rac1 cKO mice were derived from two different Cre (Le-Cre and MLR-10) transgenic mice in which lens-specific Cre expression starts at embryonic day 8.75 and 10.5, respectively, in both the lens epithelium and fiber cells. The Le-Cre/Rac1 cKO mice exhibited an early-onset (E12.5) and severe lens phenotype compared to the MLR-10/Rac1 cKO (E15.5) mice. While the Le-Cre/Rac1 cKO lenses displayed delayed primary fiber cell elongation, lenses from both Rac1 cKO strains were characterized by abnormal shape, impaired secondary fiber cell migration, sutural defects and thinning of the posterior capsule which often led to rupture. Lens fiber cell N-cadherin/ß-catenin/Rap1/Nectin-based cell-cell junction formation and WAVE-2/Abi-2/Nap1-regulated actin polymerization were impaired in the Rac1 deficient mice. Additionally, the Rac1 cKO lenses were characterized by a shortened epithelial sheet, reduced levels of extracellular matrix (ECM) proteins and increased apoptosis. Taken together, these data uncover the essential role of Rac1 GTPase activity in establishment and maintenance of lens shape, suture formation and capsule integrity, and in fiber cell migration, adhesion and survival, via regulation of actin cytoskeletal dynamics, cell adhesive interactions and ECM turnover.

Diagnóstico e tratamento do lenticone anterior / Diagnosis and therapy of anterior lenticonus

Relato de caso de um paciente de 18 anos com sindrome de Alport apresentando perda visual progressiva. A biomicroscopia revelou lenticone anterior bilateral. O paciente realizou tomografia de córnea e segmento anterior com o sistema Scheimpflug (Pentacam) e aberrometria e topografia corneana (i-Trace). O paciente foi submetido à facoemulsificação com implante de lente intraocular peça única hidrofóbica (Acrysof® SN60AT). As imagens de Scheimpflug documentaram o lenticone anterior. A aberrometria total mostrou acentuado astigmatismo miópico com acentuada aberração esférica negativa, havendo grande impacto das aberrações de alta ordem (HOA) na conversão da letra E de Snellen. O mapa de integração da aberrometria do olho todo com a topografia corneana mostrou maior semelhança das aberrrações totais com as aberrações intraoculares do que com as aberrações da superfície anterior da córnea. Após a cirurgia, o paciente apresentou acuidade visual corrigida igual a 20/20 em ambos os olhos, as imagens de Scheimpflug revelaram lentes intraoculares tópicas e os mapas diferenciais revelaram resolução da miopia e redução das aberrações da alta ordem (total e interna). Os exames de imagem foram úteis para demonstrar o impacto do lenticone anterior na qualidade visual e a resolução das aberrações ópticas após a cirurgia.

Case report of a 18-year-old male patient with Alport's syndrome, who presented with renal failure and hearing loss reporting a progressive loss of vision acuity. Slitlamp examination revealed bilateral anterior lenticonus. The patient underwent pre and post-operative corneal and anterior segment tomography with a rotating Scheimpflug system (Pentacam), integrated whole eye (individual laser beam ray tracing) and corneal surface (Placido) wavefront aberrometry (i-Trace). Phacoemulsification and single piece hydrophobic IOL implantation (Acrysof® SN60AT) was performed uneventfully in both eyes. Pre op Scheimpflug well decomented the anterior lenticonus. Total aberrometry showed myopic astigmatisms with high negative spherical aberrations OU; higher order aberrations (HOAs) greatly influenced the conversion of Snellen E letters. Total aberrations and corneal topographies integration maps OU demonstrated high levels of intraocular aberrations which had more similarity with whole eye aberrations than anterior corneal aberrations. After surgery, BCVA was 20/20 in both eyes. Scheimpflug images revealed topic intraocular lens and the differential maps showed resolution of myopia and decrease of the total ocular HOAs as well as from the internal optics. Adjunctive advanced diagnostic tools were useful to demonstrate the anterior lenticonus and its optical impact along with the resolution of the aberrations post operatively.