Anophthalmic socket in retinoblastoma: Exploring complications and risk factors in a tertiary centre in Malaysia.

PURPOSE: To evaluate the complications of anophthalmic socket in retinoblastoma patients at a tertiary centre in Malaysia. DESIGN: Retrospective study. METHODS: Patients who underwent enucleation for retinoblastoma were reviewed from 2004-2020. Details were recorded, including demographics, diagnosis, surgical techniques, implant types, additional therapies, and complications. RESULTS: Of 250 patients with retinoblastoma managed over the period, the anophthalmic sockets of 160 eyes who underwent enucleation were analysed. The mean age at enucleation was 2.03 years (26 days to 9.18 years). The follow-up periods after enucleation range from 5 days to 16.83 years. Porous polyethylene (Medpor) implants were used in 135 patients (84.4%), as were Bioceramic in 9, glass balls in 7, acrylic in 7, dermis fat grafts in 1, and silicone implants (Aurosphere) in 1. The overall complications in our study were 28.8%. Complications seen in the study included implant exposure (12.5%), shallow inferior fornix (10.6%), granuloma formation (3.1%), discharge (2.5%), implant migration (1.9%), ptosis (0.6%), and orbital dystopia (0.6%). Implant exposure is solely found in Medpor, more common in those with donor sclera caps, and exposure times range from 28 days to 11.42 years. The suturing of the Tenon and conjunctiva in separate layers significantly reduced the rate of implant exposure. Six out of seven radiation patients had shallow inferior fornixes. CONCLUSIONS: Long-term post-enucleation complications were not uncommon. Luckily, most had good outcomes, with a few needing surgical intervention. Meticulous suturing technique on the Tenon and conjunctival layer is essential to prevent implant exposure.

Intra-arterial chemotherapy for retinoblastoma: Experience from the pediatric ophthalmology referral center in Malaysia with literature review.

PURPOSE: We aimed to analyze our 4-year experience of intra-arterial chemotherapy (IAC) for retinoblastoma (RB) and to examine the tumor response, globe salvage, mortality, and safety profile of IAC in the Malaysian profile. MATERIALS AND METHODS: This was a retrospective, interventional case series. A total of 22 eyes of 20 patients with RB who underwent IAC using melphalan and topotecan from January 2018 to December 2021 in Hospital Kuala Lumpur were retrospectively reviewed. Tumor response, globe salvage, mortality, and safety profile of IAC were compared based on the International Classification of Retinoblastoma. RESULTS: The mean patient age at IAC was 21.3 months. An overall globe salvage rate of 63.6% was observed: more specifically, 100% for Group A, 75% for Groups B and C, 66.7% for Group D, and 42.9% for Group E. Poor tumor response after IAC was significantly associated with a lesser chance of globe salvage (P = 0.045). The overall rate of good tumor response following IAC was 77.3%. Specifically, rates of good tumor response in each group were 100%, 75%, 75%, 83.3% and 71.4% in group A, B, C, D and E, respectively. The mortality rate was 5%. Complications (per-catheterization) included cerebral infarct (2.2%), oxygen desaturation (2.2%), vomiting (26.1%), periorbital edema (8.8%), ptosis (6.5%), fever, femoral hematoma, and hyperpigmentation over lid (4.4% each). CONCLUSION: Four-year experience showed that IAC is a safe and effective method for RB management. Patients with a poor response after IAC may have a lower chance of globe salvage. Careful patient selection is of utmost importance to achieve the best outcome in a setting of limited health-care resources.

Monoallelic variants resulting in substitutions of MAB21L1 Arg51 Cause Aniridia and microphthalmia.

Classical aniridia is a congenital and progressive panocular disorder almost exclusively caused by heterozygous loss-of-function variants at the PAX6 locus. We report nine individuals from five families with severe aniridia and/or microphthalmia (with no detectable PAX6 mutation) with ultrarare monoallelic missense variants altering the Arg51 codon of MAB21L1. These mutations occurred de novo in 3/5 families, with the remaining families being compatible with autosomal dominant inheritance. Mice engineered to carry the p.Arg51Leu change showed a highly-penetrant optic disc anomaly in heterozygous animals with severe microphthalmia in homozygotes. Substitutions of the same codon (Arg51) in MAB21L2, a close homolog of MAB21L1, cause severe ocular and skeletal malformations in humans and mice. The predicted nucleotidyltransferase function of MAB21L1 could not be demonstrated using purified protein with a variety of nucleotide substrates and oligonucleotide activators. Induced expression of GFP-tagged wildtype and mutant MAB21L1 in human cells caused only modest transcriptional changes. Mass spectrometry of immunoprecipitated protein revealed that both mutant and wildtype MAB21L1 associate with transcription factors that are known regulators of PAX6 (MEIS1, MEIS2 and PBX1) and with poly(A) RNA binding proteins. Arg51 substitutions reduce the association of wild-type MAB21L1 with TBL1XR1, a component of the NCoR complex. We found limited evidence for mutation-specific interactions with MSI2/Musashi-2, an RNA-binding proteins with effects on many different developmental pathways. Given that biallelic loss-of-function variants in MAB21L1 result in a milder eye phenotype we suggest that Arg51-altering monoallelic variants most plausibly perturb eye development via a gain-of-function mechanism.

Duane Retraction Syndrome With Mechanical and Innervational Upshoot and Secondary Superior Rectus Contracture: A Surgical Challenge.

Duane retraction syndrome (DRS) with mechanical and innervational upshoot poses a surgical challenge. We discuss a case of DRS with mechanical and innervational upshoot and its surgical management. An 11-year-old boy presented with left eye upward deviation since birth. This deviation was worst on the right gaze. His best corrected visual acuity was 6/6 OD and 6/60 OS. Refraction showed low hyperopia with low astigmatism in both eyes. Stereoacuity was absent and there was suppression on the Worth 4 dot test in the left eye. The left eye had large hypertropia of 50 prism diopter in primary gaze. Extraocular movements showed severe upshoot and narrowing of palpebral fissures on adduction and limited abduction (-2). The patient underwent Y-splitting of the left lateral rectus (LR) muscle of 10 mm, LR recession of 4 mm, and left eye superior rectus recession of 12 mm. A marked reduction in hypertropia in primary gaze was observed on day one and at two months postoperatively with residual upshoot on adduction. His left eye deviation remained stable after six months postoperatively.

Familial exudative vitreoretinopathy in a 4 generations family of South-East Asian Descendent with FZD4 mutation (c.1501_1502del).

BACKGROUND: Familial Exudative Vitreoretinopathy (FEVR) is a hereditary disorder characterized by peripheral avascular retina with neovascularization. Although FEVR has been thoroughly described in multiple literature publications from different countries, there are currently limited articles describing the phenotypes of FEVR among South-East Asian Descendent. This paper describes the clinical phenotype of the FZD4 gene with c.1501_1502 deletion in a 4-generation case series of a South East Asian family. METHODS: We reviewed a 4-generation case series of a South-East Asian descendent family consisting of 27 family members with 10 members diagnosed with FEVR. We observed the clinical phenotype of these series of patients, including some of the family members who underwent whole-exome sequencing, PCR amplification and DNA sequencing techniques to identify the mutated gene. RESULTS: Frameshift mutation (c.1501_1502del) were found in FZD4 gene in this series of patients with the age ranging from 1 month old to 69 years old. There was a 100% (4/4) of our paediatric patients being diagnosed within 21 days of life. It was also found that 75% of patients (6/8) less than 40 years old exhibited disease asymmetry of 2 stages or more and 80% (8/10) had a history of vitreoretinal surgery or diode laser photocoagulation, with a further 50% of the adult patients identified as legally blind; the mean age of blindness was 18-years-old. CONCLUSIONS: Phenotypic manifestation of FZD4 gene with c.1501_1502del mutation can be identified within the neonatal period. They have relatively greater clinical asymmetry of 2 stages or more compared to other mutations. Without treatment, most of them will have bilateral severe visual impairment around the adolescent age group.

Optic Neuropathy in an Autistic Child With Vitamin A Deficiency: A Case Report and Literature Review.

An eight-year-old boy with autism developed gradual onset of vision loss and nyctalopia. Dietary history revealed a diet of only French fries and potato chips for the past four years. As a result, serum vitamin A was severely below the normal level. Ophthalmologic examination revealed a normal anterior segment with bilateral optic atrophy. Vitamin A supplementation was given to restore to normal level; however, the visual impairment was irreversible. Vitamin A deficiency is common in developing countries; however, to the best of our knowledge, there are no other reported cases of permanent visual loss secondary to vitamin A deficiency in Malaysia.

Vision-related Quality of Life in Malaysian Children with Threshold and Prethreshold Retinopathy of Prematurity.

PURPOSE: The prevalence of retinopathy of prematurity (ROP) is higher in developing countries compared to developed countries. There is limited data on vision-related quality of life (VRQoL) among children with severe type of ROP in developing countries. This study evaluated the influence of threshold and prethreshold ROP on VRQoL in Malaysian children. METHODS: Multicenter prospective cross-sectional study conducted in three tertiary hospitals in 2018 to 2019. Children less than 7 years old with previous ROP diagnosis were recruited. Patients with systemic comorbidities that affected vision or daily activities were excluded. A parent or guardian completed the Children's Visual Function Questionnaire (CVFQ) for the assessment of child's general health, general vision, competence, personality, family impact, and treatment difficulty. RESULTS: Eight were categorized with threshold ROP, 16 with high-risk prethreshold ROP, and 26 with low-risk prethreshold ROP. Fifty age-matched controls were also included. Mean visual acuity in logarithm of the minimum angle of resolution was 0.46 in the threshold, 0.08 in high-risk prethreshold, and 0.01 in low-risk prethreshold subgroups. Threshold ROP was associated with myopia and strabismus, and associated with poor visual acuity compared to prethreshold ROP. Mean total CVFQ score was significantly lower in the ROP group (p < 0.001) compared to the control group. Mean score and all mean subscale scores were significantly lower in the threshold subgroup compared to high-risk and low-risk prethreshold subgroups, with lowest subscale scores on general vision and general health. There was significant association between gestational age, visual acuity of the better eye, family income, and VRQoL (p < 0.05). CONCLUSIONS: ROP was associated with lower VRQoL in children born prematurely in Malaysia. The threshold ROP group is the most affected. General vision and health domains are their main difficulties encountered. Gestational age, visual acuity of the better eye, and family income affects the VRQoL.

Neonatal eye screening for 203 healthy term new-borns using a wide-field digital retinal imaging system.

BACKGROUND: The current practice for new-born eye examination by an Ophthalmologist in Malaysian hospitals is limited to only preterm new-borns, syndromic or ill infants. Healthy term new-borns are usually discharged without a thorough eye examination. This study is aimed at determining the proportion and types of ocular abnormalities detected in purportedly healthy term new-borns. METHOD: This cross-sectional study is comprised of 203 participants, all purportedly healthy term new-born infants from the Obstetrics and Gynaecology ward at Hospital Kuala Lumpur over a 6 months period. The examination list includes external eye examination, red reflex test, and fundus imaging using a wide-field digital retinal imaging system (Phoenix Clinical ICON Paediatric Retinal Camera) by a trained Investigator. The pathologies detected were documented. The results were compared and correlated with similar studies published in the literature previously. RESULTS: Total ocular abnormalities were detected in 34% of the infants. The most common finding was retinal haemorrhage in 29.6% of the infants, of which 53.3% occurred bilaterally. Spontaneous vaginal delivery (SVD) remained the greatest risk factor which has nearly 3.5 times higher risk of new-borns developing retinal haemorrhage compared to Lower Segment Caesarean Section (LSCS). There was a 6% increased likelihood of developing retinal haemorrhage for every 1-min increment in the duration of 2nd stage of labour. CONCLUSION: Universal eye screening for all new-borns using a wide-field digital imaging system is realistically possible, safe, and useful in detecting posterior segment disorders. The most common abnormality detected is retinal haemorrhage.

Intra-arterial chemotherapy for retinoblastoma: Our first three-and-a-half years' experience in Malaysia.

AIM: To report our first three-and-a-half years' experience with intra-arterial chemotherapy (IAC) in managing retinoblastoma (RB). METHODS: Single institution, retrospective, interventional case series of 14 retinoblastoma patients managed with IAC from December 2014 to June 2018. Demographics were described. Outcomes measures were tumor response, treatment complications and globe salvage. RESULTS: Subjects' mean age at the first administration of IAC was 31.4 months. 57.1% of the eyes were Group D and E retinoblastoma, while 79% were bilateral disease. 93% of the eyes were as secondary treatment. Of 32 IAC cannulations performed, 23 (71.8%) were successful and received chemotherapy drug melphalan. Each eye received a mean of 1.8 (range 1-4) IAC injections. 53% of the eyes showed regression post treatment. After a mean follow up period of 19 months, globe salvage rate was 38%. Most of the adverse effects experienced were localized and transient. CONCLUSION: IAC has provided an added recourse in the armamentarium of retinoblastoma treatment in our center. IAC treatment is a viable alternative in the treatment of retinoblastoma to salvage globe, for eyes that would conventionally require enucleation especially in bilateral disease.

Spectrum of germ-line RB1 gene mutations in Malaysian patients with retinoblastoma.

PURPOSE: The availability of molecular genetic testing for retinoblastoma (RB) in Malaysia has enabled patients with a heritable predisposition to the disease to be identified, which thus improves the clinical management of these patients and their families. In this paper, we presented our strategy for performing molecular genetic testing of the RB1 gene and the findings from our first 2 years of starting this service. METHODS: The peripheral blood of 19 RB probands, including seven bilateral and 12 unilateral cases, was obtained, and genomic DNA was extracted. Analysis of the RB1 exons and the promoter region was conducted first using PCR and direct sequencing. Next, multiplex ligation-dependent probe amplification (MLPA) analysis was performed for patients whom the first results were negative. For patients whom either the first or second method results were positive, parental samples were analyzed to determine the origin of the mutation. RESULTS: Ten RB1 mutations were identified in ten (52.6%) of the 19 probands (seven bilateral and three unilateral cases), of which 30.0% (3/10) was identified with MLPA. The detection rates in the bilateral and unilateral cases were 100.0% (7/7) and 25.0% (3/12), respectively. Three new RB1 mutations were discovered, two in patients with bilateral RB and one in patient with unilateral RB. Interestingly, all mutations detected with the PCR-sequencing method were predicted to create a premature stop codon. Eight mutations were proven to be de novo while one mutation was inherited from the mother in a family with a positive history of RB. CONCLUSIONS: Our results confirmed the heterogeneous nature of RB1 mutations and the predominantly de novo origin. The high prevalence of pathogenic truncating mutations was evident among local patients with RB. The combination of PCR sequencing and MLPA is recommended for sensitive identification of heritable RB cases.

Presentation of retinoblastoma patients in Malaysia.

BACKGROUND: Retinoblastoma is a rare type of cancer that usually develops in early childhood. If left untreated it can cause blindness and even death. The aim of this study is to determine sociodemographic and clinical features of retinoblastoma patients and also to determine the treatment pattern and outcome in Malaysia. MATERIALS AND METHODS: Data for this study were retrieved from the Retinoblastoma Registry of the National Eye Database (NED) in Malaysia. Hospital Kuala Lumpur, Hospital Umum Kuching, Sarawak and Hospital Queen Elizabeth, Kota Kinabalu were the major source data providers for this study. Data collected in the registry cover demography, clinical presentation, modes of treatment, outcomes and complications. RESULTS: The study group consisted of 119 patients (162 eyes) diagnosed with retinoblastoma between 2004 and 2012. There were 68 male (57.1%) and 51 (42.9%) female. The median age at presentation was 22 months. A majority of patients were Malays (54.6%), followed by Chinese (18, 5%), Indians (8.4%), and indigenous races (15.9%). Seventy six (63.8%) patients had unilateral involvement whereas 43 patients had bilateral disease (36.1%). It was found that most children presented with leukocoria (110 patients), followed by strabismus (19), and protopsis (12). Among the 76 with unilateral involvement (76 eyes), enucleation was performed for a majority (79%). More than half of these patients had extraocular extension. Of the 40 who received chemotherapy, 95% were given drugs systemically. Furthermore, in 43 patients with bilateral involvement (86 eyes), 35 (41%) eyes were enucleated and 17 (49%) showed extraocular extension. Seventy-two percent of these patients received systemic chemotherapy. The patients were followed up 1 year after diagnosis, whereby 66 were found to be alive and 4 dead. Sixteen patients defaulted treatment and were lost to follow-up, whereas follow-up data were not available in 33 patients. CONCLUSIONS: Patients with retinoblastoma in this middle-income Asian setting are presenting at late stages. As a result, a high proportion of patients warrant aggressive management such as enucleation. We also showed that a high number of patients default follow-up. Therefore, reduction in refusal or delay to initial treatment, and follow-up should be emphasized in order to improve the survival rates of retinoblastoma in this part of the world.

Laser-assisted subepithelial keratectomy for anisometropic amblyopia in children: outcomes at 1 year.

PURPOSE: To assess the refractive, visual acuity, and binocular results of laser-assisted subepithelial keratectomy (LASEK) for anisomyopia, anisohyperopia, and anisoastigmatia in children with various levels of amblyopia secondary to the anisometropic causes. SETTING: Nonhospital surgical facility with follow-up in a hospital clinic setting. METHODS: This retrospective review was of 53 children with anisometropia who had LASEK to correct the refractive difference between eyes. All LASEK procedures were performed using general anesthesia. Patients were divided into 3 groups according to their anisometropia as follows: myopic difference greater than 3.00 diopters (D), astigmatic difference greater than 1.50 D, and hyperopic difference greater than 3.50 D. The children were followed for at least 1 year, and their refractive status, visual acuity, and binocular vision were assessed and recorded at 2 and 6 months as well as 1 year. RESULTS: The mean age at treatment was 8.4 years (range 10 months to 16 years). The mean preoperative anisometropic difference was 6.98 D in the entire group, 9.48 D in the anisomyopic group, 3.13 D in the anisoastigmatic group, and 5.50 D in the anisohyperopic group. One year after LASEK, the mean anisometropic difference decreased to 1.81 D, 2.43 D, 0.74 D, and 2.33 D, respectively, and 54% of all eyes were within +/-1.00 D of the fellow eye, 68% were within +/-2.00 D, and 80% were within +/-3.00 D. Preoperative visual acuity and binocular vision could be measured in 33 children. Postoperatively, 63.6% of children had an improvement in best corrected visual acuity (BCVA) and the remainder had no noted change. No patient had a reduction in BCVA or a loss in fusional ability after LASEK. Of the 33 children, 39.4% had positive stereopsis preoperatively and 87.9% had positive stereopsis 1 year after LASEK. CONCLUSION: Laser-assisted subepithelial keratectomy is an effective surgical alternative to improve visual acuity in anisometropic children unable to tolerate conventional methods of treatment or in whom these methods fail.