The genetic differences between types 1 and 2 in von Hippel-Lindau syndrome: comprehensive meta-analysis.

BACKGROUND: Patients with von Hippel-Lindau (VHL) disease are at risk of developing tumors in the eye, brain, kidney, adrenal gland, and other organs based on their gene mutations. The VHL tumor suppressor gene contains pathogenic variants responsible for these events. This meta-analysis aims to investigate the genetic differences among the various types of VHL syndrome and their correlation with the location of mutations (exons and domains) in the VHL gene. METHOD: Papers eligible for publication until September 2023 were identified using the electronic databases of PubMed, Google Scholar, Scopus, and EMBASE. The Random Effect model was utilized to evaluate the genetic differences between type 1 and type 2 VHL syndromes. RESULTS: The prevalence of missense mutations (MSs) was found to be 58.9% in type 1, while it was 88.1% in type 2. Interestingly, the probability of observing MSs in type 1 was 0.42 times lower compared to type 2. The mutation hotspots of the VHL gene were R167Q/W, Y98H, R238W, and S65L, respectively. Although type 2 had a high presentation of Y98H and R238W, it did not have a higher S65L than type 1. The analysis demonstrated a statistically significant higher prevalence of truncated mutations (PTMs) in type 1. Among type 1, large/complete deletions (L/C DELs) were found in 16.9% of cases, whereas in type 2 only 3.7%. This difference was statistically significant with a p-value < 0.001. Overall, the probability of identifying mutations in domain 2 compared to domain 1 was found to be 2.13 times higher in type 1 (p-value < 0.001). Furthermore, the probability of detecting exon 1 in comparison with observing exon 2 in type 1 was 2.11 times higher than type 2 and revealed a statistically significant result (p-value < 0.001). The detection of exon 2 was 2.18 times higher in type 1 (p-value < 0.001). In addition, the likelihood of discovering exon 2 compared with others was significantly lower in type 1 compared with type 2 VHL (OR = 0.63, p-value = 0.015). CONCLUSIONS: We have revealed a comprehensive genetic difference between types 1 and 2 of VHL syndrome. The significant differences in MS, PTMs, L/C DELs, and the location of the mutations between type 1 and type 2 VHL patients in the Asian, European, and American populations emphasize the genetic heterogeneity of the syndrome. These findings may pave the way for the diagnosis, treatment, and further investigation of the mechanisms behind this complex genetic disorder.

Review: New horizons in retinoblastoma treatment: an updated review article.

Retinoblastoma (Rb) is a rare childhood intraocular malignancy with an incidence rate of approximately 9000 children per year worldwide. The management of Rb is inherently complex and depends on several factors. The orders of priorities in the treatment of Rb are saving life, globe salvage and vision salvage. Rarity and the young age at diagnosis impede conducting randomized clinical trials (RCTs) for new therapeutic options, and therefore pre-RCTs studies are needed. This review provides an overview of advances in Rb treatment options, focusing on the emergence of new small molecules to treat Rb. Articles related to the management and treatments of Rb were searched in different databases. Several studies and animal models discussing recent advances in the treatment of Rb were included to have a better grasp of the biological mechanisms of Rb. Over the years, the principles of management and treatment of Rb have changed significantly. Innovations in targeted therapies and molecular biology have led to improved patient and ocular survival. However, there is still a need for further evaluation of the long-term effects of these new treatments.

Ruthenium-106 plaque radiotherapy for uveal melanoma: analysis of tumor dimension and location on anatomical and functional results.

BACKGROUND: To report the long-term outcomes of Ru-106 plaque radiotherapy in eyes with uveal melanoma (UM) and to assess the effect of tumor thickness and location on final outcomes. METHODS: Medical records of 234 patients undergoing Ru-106 plaque radiotherapy for UM were reviewed, and the visual outcome, globe preservation, and patient survival were evaluated. The results of 2 groups were compared: 1. between thin (small and medium-sized, thickness < 7 mm, 148 eyes [63.2%]) and thick (thickness ≥ 7 mm, 86 eyes [36.8%]) tumors, and 2. between large (largest basal diameter [LBD] > 12 mm, 109 eyes [46.6%]) and medium/small (LBD ≤ 12 mm, 125 eyes [53.4%]). In addition, a comparison of the juxtapapillary location in 46 eyes (19.7%) versus tumors arising elsewhere and between tumors with and without ciliary involvement in 48 eyes (21.5%) were done. RESULTS: The patients were followed for a median of 54.2 months (range: 6-194.5 months). After adjusting for baseline visual acuity (VA), there was no significant association between final VA and different dimension and tumor location groups. Final globe preservation was 91.9%, and there was no significant difference between different dimension- and ciliary body involvement groups regarding anatomical success rate. The juxtapapillary tumors had lower globe preservation (80.4% vs .94.7%, p = 0.002). The hazard ratio (HR) for enucleation in juxtapapillary tumors was HR = 6.58 (95-CI: 3.84 to 11.21). The overall metastasis rate was 6.8%, with no significant difference in juxtapapillary tumors (4.3% vs.7.4%, p = 0.455). CONCLUSIONS: Ru-106 plaque radiotherapy is an effective treatment for thick and large UM. With this type of treatment, the globe preservation rate is lower in juxtapapillary tumors, but there is no significant difference in the metastasis rate.

Ru-106 plaque radiotherapy for vasoproliferative tumors of retina: a 15-year single-center experience.

PURPOSE: This study evaluates the outcomes of ruthenium-106 (Ru-106) plaque brachytherapy for vasoproliferative tumors (VPTs) of the ocular fundus in a single referral ocular oncology center. METHODS: The clinical charts of all patients diagnosed with VPT who underwent plaque radiotherapy from 2002 to 2017 were reviewed. Clinical features, types of treatment, outcomes and complications were evaluated. RESULTS: Of 46 patients with VPT diagnosis in our ocular oncology clinic, 25 (54.34%) cases were treated with Ru-106 plaque brachytherapy. Eleven patients (44%) were male, and the mean age at the time of diagnosis was 40.92 ± 13.11 years. The mean follow-up time was 47.56 ± 36.87 months. Inferotemporal quadrant was the most common site of the tumor (64.00%). The mean delivered apex and scleral dose was 101.56 ± 6.51 and 412.26 ± 113.66 Gray (Gy), respectively. Initial tumor length, width and thickness were 10.26 ± 3.42, 8.05 ± 2.83 and 4.27 ± 1.10 mm, respectively. The mean tumor thickness decreased to 2.60 ± 0.63 mm, postoperatively. Complete resolution of subretinal fluid around the tumor was achieved in 81.80% of cases. Visual acuity was more than 20/400 in 64% of patients before treatment and 60% of patients at last follow-up. CONCLUSION: Our study showed that Ru-106 plaque radiotherapy is an effective and safe method of treatment in VPTs.

RUTHENIUM-106 BRACHYTHERAPY IN THE TREATMENT OF CIRCUMSCRIBED CHOROIDAL HEMANGIOMA.

PURPOSE: To examine the efficacy and safety of Ruthenium-106 plaque radiotherapy in the treatment of circumscribed choroidal hemangioma. METHODS: Twenty-one eyes of 21 patients diagnosed with symptomatic circumscribed choroidal hemangioma who underwent Ruthenium-106 plaque radiotherapy were included in the study. Clinical response, ancillary tests finding improvement, and major side effects were evaluated. RESULTS: From the initial to the 1-year follow-up visits, vision improved in 12 eyes (57%), was stable in 7 eyes (33%), and became worse in 2 eyes (10%). Based on fluorescein angiography and optical coherence tomography, subretinal fluid and cystoid macular edema resolved in all patients. Changes in logarithm of minimum angle of resolution visual acuity (P = 0.038); tumor thickness (P = 0.0001) and largest diameter (P = 0.007) on ultrasonography; and subfoveal thickness on optical coherence tomography (P < 0.0001), were statistically significant between the initial and the 1-year follow-up visits. Side effects as observed during the follow-up period included: radiation-related retinopathy in 5 (24%) eyes, radiation-related papillopathy in 1 eye (5%), and subretinal fibrosis in 2 eyes (10%). Subretinal fibrosis was the only permanent radiation-related side effect. CONCLUSION: Ruthenium-106 plaque radiotherapy is an effective and safe method of treatment for symptomatic circumscribed choroidal hemangiomas. The incidence of permanent visual loss is low with prompt treatment of complications.

Clinical predictive factors and imaging biomarkers of treatment response to half dose PDT in patients with chronic central serous chorioretinopathy.

PURPOSE: To determine the clinical and imaging biomarkers of the response to half-dose photodynamic therapy (HD-PDT) in patients with central serous chorioretinopathy (CSC) METHODS: Clinical records and baseline ophthalmic images of 67 chronic CSC patients who underwent HD-PDT were assessed. In addition to demographic data, optical coherence tomography (OCT), fluorescein angiography (FA) and fundus autofluorescence (FAF) images were analyzed for specific biomarkers. The patients were categorized to early responder and late responder based on the time needed for complete resolution of subretinal fluid after PDT (less than 1 month vs. more than 1 month). The baseline clinical and imaging biomarkers were compared between the two groups. RESULTS: Seventy-three eyes of 67 patients were included in the study. The mean response time to PDT was 1.63 ± 1.48 months with 82.2% (60/73) of eyes categorized as early responder. The mean response time to PDT in delayed-response group was 4.15±1.51 months. In multivariate analysis, delayed response to PDT was associated with lacking history of systemic corticosteroid consumption, lacking history of pretreatment with eplerenone or acetazolamide before PDT and presence of hyperreflective foci in baseline OCT images (all p values < 0.05). There was no association between final visual outcome and late response to PDT. CONCLUSION: The presence of inflammatory biomarkers such as hyperreflective foci in baseline OCT images might be indicative of resistance to PDT. Moreover, the effect of pretreatment with mineralocorticoid antagonist on the response to PDT in chronic CSC should be explored in future prospective studies.

Congenital simple hamartoma of the retinal pigment epithelium: 4 cases with multimodal imaging.

BACKGROUND: Congenital simple hamartoma of the retinal pigment epithelium is often identified as an incidental finding. One important issue is the differentiation of these benign lesions from other lesions which could be potentially sight-threatening. METHODS: This study describes 4 cases of congenital simple hamartoma of the retinal pigment epithelium that were referred to a university-based hospital. Multimodal imaging including fundus photo, multicolor fundus photo, fundus autofluorescence, optical coherence tomography (OCT), OCT angiography, fluorescein angiography and multifocal electroretinogram is provided. RESULTS: The first case is a young man with an incidental finding of this lesion. The second and third cases are diabetic patients with congenital simple hamartoma of the retinal pigment epithelium and diabetic macular edema and the fourth one is a case of congenital simple hamartoma of the retinal pigment epithelium with a full-thickness macular hole. CONCLUSIONS: Differentiation of congenital simple hamartoma of the retinal pigment epithelium from other potentially sight-threatening lesions is important. Multimodal imaging can be helpful regarding this issue. Besides typical findings described in the literature, unique features in our cases include concurrent diabetic macular edema and association with a full-thickness macular hole.

Fluorescein versus Indocyanine Green Angiography Guided Half-Dose Photodynamic Therapy for Chronic Central Serous Chorioretinopathy.

Purpose: To compare the outcomes of fluorescein angiography (FA)-guided and indocyanine green angiography (ICGA)-guided half-dose photodynamic therapy (PDT) in patients with chronic central serous chorioretinopathy (CSC). Methods: In this retrospective comparative study, medical records of eyes with chronic CSC who underwent half-dose PDT were reviewed. A retina specialist performed FA-guided half-dose PDT, and the other performed ICGA-guided treatment. The success of applying PDT in the resolution of subretinal fluid was compared between the FA- and ICGA-guided methods. Results: Eighty-two eyes of 73 patients (41 eyes in each group) received half-dose PDT. After half-dose PDT, a significant improvement in the best-corrected visual acuity (BCVA) was found at the time of the last follow-up in both groups (both P < 0.001), with no significant intergroup difference. Central subfield and subfoveal choroidal thicknesses decreased significantly in both groups at the last follow-up (all P < 0.05), with no significant differences between the groups. Subretinal fluid (SRF) resolved in all eyes, and no persistent SRF was detected during the follow-up period. Conclusion: FA-guided and ICG-guided half-dose PDT may have similar efficacy for the treatment of chronic CSC.

Prevalence of Neurological Symptoms and Imaging Findings in Von Hippel-Lindau Patients Referred to Rasool Akram Hospital, 2018-2021.

This study aimed to assess the prevalence of neurological symptoms and related imaging findings in patients with von Hippel-Lindau (VHL) at Rasool Akram Hospital from September 2018 to September 2021. This analytical observational study examined eligible patients over the period from September 2018 to September 2021. We collected demographic information (age, gender) along with imaging findings and results of neurological and eye examinations. Comparison between qualitative variables was also done using the Chi-square test or Fisher's exact test. Also, an independent t-test was used to compare quantitative variables between the two groups. SPSS version 22 software was used for statistical analysis of data. A significant level was considered less than or equal to 0.05. Of the 54 examined patients (48.1% were male and 51.9% were female) with an average age of 36.42 ± 13.37 years. A significant majority (87.0%) reported a positive family history of the disease. The most common type of disease was Type 1 observed in 94.4% of cases and Type 2A was the next most frequent (3.7%). The most common pattern of retinal pathological lesions seen in the examination was related to bilateral lesions (79.6%). The most common pathological finding was related to the presence of a mass in cerebellar magnetic resonance imaging (48.1%). Considering the findings of the present study, which highlight a significant frequency of bilateral retinal lesions as well as masses in the central nervous system and endocrine system, it is evident that patients require careful follow-up and various interventions after being diagnosed with the disease. This approach is essential to manage and potentially mitigate the complications associated with these conditions.

Screening for large rearrangements of the RB1 gene in Iranian patients with retinoblastoma using multiplex ligation-dependent probe amplification.

PURPOSE: To screen deletions/duplications of the RB1 gene in a large cohort of Iranian patients using the multiplex ligation-dependent probe amplification (MLPA) technique. METHODS: A total of 121 patients with retinoblastoma, involving 55 unilateral and 66 bilateral or familial retinoblastomas, were included in this study. Among these patients, 121 blood and 43 tissue samples were available. DNA was extracted from the blood and tissue samples and analyzed with an RB1-specific MLPA probe set. The mutation findings were validated with SYBR Green Real-Time PCR. RESULTS: Twenty-two mutations were found in 21 patients; of these, ten mutations were detected in patients with isolated unilateral retinoblastoma. CONCLUSIONS: Our results suggested that MLPA is a fast, reliable, and powerful method for detecting deletions/duplications in patients with retinoblastoma.

Incidence of acute endophthalmitis after intravitreal bevacizumab injection in a single clinical center.

PURPOSE: To assess the rate of infectious endophthalmitis in a single clinical center in Iran and to compare the rate of endophthalmitis in patients receiving postinjection antibiotics with those who did not. METHODS: A retrospective chart review of patients who received intravitreal injections of bevacizumab was undertaken. Cases of clinical diagnoses of endophthalmitis were reviewed. Bevacizumab was obtained at the time of injection from a commercially available vial after aseptic cleansing of the rubber cover. RESULTS: Five patients (six eyes) developed clinical endophthalmitis after the intravitreal bevacizumab injection. The risk per injection was 0.10% (6/5,901). One culture-positive case was found overall. Postinjection antibiotic drops were prescribed for 68% of eyes. All endophthalmitis cases were among those who received postoperative antibiotic eye drops. The difference in the rates of endophthalmitis between those receiving postinjection antibiotics and those who did not was not statistically significant (P = 0.18). CONCLUSION: A low risk of endophthalmitis consistent with the range of previous studies was observed notwithstanding the usage of multiple use of a single vial. Postinjection antibiotic drops may not be necessary.

Double Retina Sign: A New Optical Coherence Tomography Finding in Combined Hamartoma of the Retina and Retinal Pigment Epithelium.

Purpose: To describe a case of combined hamartoma of the retina and retinal pigment epithelium (CHRRPE) with peculiar optical coherence tomography (OCT) findings. Methods: Case report. Results: A 7-year-old girl with a history of decreased visual acuity in the left eye since early childhood presented with pigmented epiretinal membrane in favor of CHRRPE based on clinical and paraclinical findings. In OCT images, an area of retinal defect was noted, and the retina doubled up on itself near the defect (double retina sign). Conclusion: Careful examination of OCT images in patients with CHRRPE can reveal new findings.

Cystoid macular oedema without leakage in fluorescein angiography: a literature review.

Cystoid macular oedema (CMO), which is defined as a macular thickening and cystic changes due to accumulation of fluid, could be asymptomatic and only diagnosed using paraclinical techniques. Fluorescein angiography (FA) and optical coherence tomography (OCT) are useful in detecting CMO in clinical practice. Non-leaking CMO, also known as angiographically silent CMO, is referred to as cases of CMO without leakage in fluorescein angiography. This type of CMO has been reported in some retinal dystrophies, in cases of maculopathy as a side effect of certain drugs, and also in some systemic disorders. The exact mechanism and treatment options for this type of CMO are still not clear. This literature review aims to discuss different causes of non-leaking CMO, proposed mechanisms, and management options. Three sections including drugs, retinal dystrophies, and systemic disorders are discussed in this review.

Stem Cell Therapy in Stargardt Disease: A Systematic Review.

This article aimed to review current literature on the safety and efficacy of stem cell therapy in Stargardt disease. A comprehensive literature search was performed, and two animal and eleven human clinical trials were retrieved. These studies utilized different kinds of stem cells, including human or mouse embryonic stem cells, mesenchymal stem cells, bone marrow mononuclear fraction, and autologous bone marrow-derived stem cells. In addition, different injection techniques including subretinal, intravitreal, and suprachoroidal space injections have been evaluated. Although stem cell therapy holds promise in improving visual function in patients with Stargardt disease, further investigation is needed to determine the long-term benefits, safety, and efficacy in determining the best delivery method and selecting the most appropriate stem cell type.

Synthesis and evaluation of modified lens using plasma treatment containing timolol-maleate loaded lauric acid-decorated chitosan-alginate nanoparticles for glaucoma.

Reducing intraocular pressure (IOP) with eye drops is one of the most common ways to control glaucoma. Low bioavailability and high frequency of administration in eye drops are major challenges in ocular pharmacotherapy. Contact lenses have attracted the attention of scientists in recent decades as an alternative method. In this study, with the aim of long-term drug delivery and better patient compatibility, contact lenses with surface modification and nanoparticles were used. In this study, timolol-maleate was loaded into polymeric nanoparticles made of chitosan conjugate with lauric acid and sodium alginate. Then silicon matrix was mixed with a curing agent (10:1), and the suspension of nanoparticles was added to the precursor and cured. Finally, for surface modification, the lenses were irradiated with oxygen plasma at different exposure times (30, 60, and 150 s) and soaked in different BSA concentrations (1, 3, and 5% w/v). The results showed nanoparticles with a size of 50 nm and a spherical shape were synthesized. The best surface modification of the lenses was for 5 (% w/v) albumin concentration and 150 s exposure time, which had the highest increase in hydrophilicity. Drug release from nanoparticles continued for 3 days and this amount increased to 6 days after dispersion in the modified lens matrix. The drug model and kinetic study show the Higuchi model completely supported the release profile. This study represents the novel drug delivery system to control intra-ocular pressure as a candidate platform for glaucoma treatment. Improved compatibility and drug release from the designed contact lenses would prepare new insight into the mentioned disease treatment.

Investigation of germline VHL variants in Iranian patients with retinal capillary hemangioblastoma and genotype-phenotype analysis.

BACKGROUND: Retinal capillary hemangioblastoma (RCH), while sporadic in some cases, is the most common and earliest manifestation of von Hippel-Lindau disease (VHL). This is the first report on different types of VHL variants and genotype-phenotype correlations in Iranian families with RCH. MATERIALS AND METHODS: In this prospective observational case series study, 17 families with RCH were included. PCR was performed to amplify 3 exons of VHL gene. Afterward, Sanger sequencing was performed on all PCR products. For the detection of VHL copy number variations, MLPA was used. RESULTS: Our study identified 10 different types of VHL variants. Missense mutations were the most common variants found and affected the structure of α domain of the VHL protein (pVHL). The majority of mutations (72.7%) in the patients with RCH and central nervous system hemangioblastoma (CNS-HB) were located on α domain. CONCLUSION: α domain of VHL may play a potential role in the pathogenesis of RCH. Our findings suggest that genotype-phenotype characteristics in those variants in α- domain may predispose patients to RCH with CNS-HB.

Targeted chemotherapy in retinoblastoma: A step forward from patient survival to globe survival.

BACKGROUND/ OBJECTIVES: Despite being the most common intraocular malignancy in childhood, there is a substantial disparity between developing and developed countries in terms of patient and globe survival in retinoblastoma (Rb). The current study intends to determine patient and globe survival before and after the introduction of the new targeted treatment modalities in a developing country. METHODS: Medical records of 350 patients (516 eyes) with retinoblastoma referred to a tertiary referral center for Rb in Tehran, Iran, were reviewed. In order to compare patient and globe survival before and after the availability of the new treatment modalities, including intra-arterial and intravitreal chemotherapy, the patients were divided into group 1 (2001-2007) and group 2 (2008-2018) based on the calendar period of diagnosis. RESULTS: Two-hundred-twenty-three eyes of 149 patients and 293 eyes of 201 patients were categorized into groups 1 and 2, respectively. The 5-year patient survival was 97% across the current survey, and the overall survival rate was 96% in group 1 and 99% in group 2 (P = 0.08). Overall, 50% of eyes with retinoblastoma underwent enucleation, which was the primary in 63% (116/184) of the unilateral and 30% (99/322) of the bilateral cases. Primary enucleation was significantly lower in group 2 (35%) in contrast to group 1 (50%) (P < 0.001). In addition, globe survival improved significantly in the International Classification of Retinoblastoma Groups D (17% in group 1 vs. 66% in group 2, P < 0.001) and E (1% in group 1 vs. 23% in group 2 P < 0.001) during the two timelines. In enucleated eyes, despite the increased rate of prelaminar involvement in group 2 (13% vs. 2% in group 1, P = 0.003), the rate of high-risk histopathologic findings was similar between the two groups. CONCLUSION: Similar to developed countries, the application of new targeted treatment modalities, including intra-arterial and intravitreal chemotherapy, has been associated with significantly improved globe survival in Rb patients. However, it should be noted that even with the availability of these novel treatment options, the decision for on-time enucleation should not be deferred.

Semi-supervised segmentation of retinoblastoma tumors in fundus images.

Retinoblastoma is a rare form of cancer that predominantly affects young children as the primary intraocular malignancy. Studies conducted in developed and some developing countries have revealed that early detection can successfully cure over 90% of children with retinoblastoma. An unusual white reflection in the pupil is the most common presenting symptom. Depending on the tumor size, shape, and location, medical experts may opt for different approaches and treatments, with the results varying significantly due to the high reliance on prior knowledge and experience. This study aims to present a model based on semi-supervised machine learning that will yield segmentation results comparable to those achieved by medical experts. First, the Gaussian mixture model is utilized to detect abnormalities in approximately 4200 fundus images. Due to the high computational cost of this process, the results of this approach are then used to train a cost-effective model for the same purpose. The proposed model demonstrated promising results in extracting highly detailed boundaries in fundus images. Using the Sørensen-Dice coefficient as the comparison metric for segmentation tasks, an average accuracy of 93% on evaluation data was achieved.

Long-term follow-up of invasive ocular surface squamous cell carcinoma treated with excision, cryotherapy, and topical mitomycin C.

BACKGROUND: To evaluate the efficacy of surgical excision, cryotherapy and topical Mitomycin C (MMC) for ocular surface squamous cell carcinoma (SCC) with at least 24 months follow-up. METHODS: Seventeen patients with primary and recurrent invasive SCC of ocular surface underwent surgical excision and map biopsy of the margins, and double freeze-thaw cryotherapy of the bed and margins. Topical MMC (0.04%, 4 times daily) was commenced 7-10 days after operation. It was delivered in cycles that consisted of medication 4 times daily for 7 consecutive days followed by 7 consecutive days of no medication. Patients with primary SCC received two cycles (protocol 1) and those with recurrent SCC received three cycles (protocol 2). Patients with intra-ocular and or orbital extension or those with less than 24 months of follow-up were excluded. The frequency of tumor recurrence and complications associated with treatment were measured. RESULTS: Mean age was 70.7 years (SD = 10, range: 48-80). Mean follow-up time was 48 months (SD = 21, range: 24-89). There were 12 patients with primary SCC and five with recurrent SCC. Mean largest diameter was 9.7 mm (3-20). Surgical margins were free in 12 cases. One patient with recurrent SCC who received protocol 2 treatment developed recurrence 9 months after excision, and remained free of recurrence 24 months after second treatment. Complications comprised transient mild punctate corneal epithelial erosion (eight), irritation and conjunctival hyperemia (11), corneal scar (six), and scleral thinning (three). All except one responded well to conservative management. One scleral thinning required scleral patch graft 1 year after treatment. CONCLUSION: The combination of surgical excision, cryotherapy, and post-operative topical mitomycin-C was effective treatment for ocular surface invasive SCC in long-term follow-up.

Human-induced pluripotent stem cells-derived retinal pigmented epithelium, a new horizon for cells-based therapies for age-related macular degeneration.

Retinal pigment epithelium (RPE) degeneration is the hallmark of age-related macular degeneration (AMD). AMD, as one of the most common causes of irreversible visual impairment worldwide, remains in need of an appropriate approach to restore retinal function. Wet AMD, which is characterized by neovascular formation, can be stabilized by currently available therapies, including laser photocoagulation, photodynamic therapy, and intraocular injections of anti-VEFG (anti-vascular endothelial growth factor) therapy or a combination of these modalities. Unlike wet AMD, there is no effective therapy for progressive dry (non-neovascular) AMD. However, stem cell-based therapies, a part of regenerative medicine, have shown promising results for retinal degenerative diseases such as AMD. The goal of RPE cell therapy is to return the normal structure and function of the retina by re-establishing its interaction with photoreceptors, which is essential to vision. Considering the limited source of naturally occurring RPE cells, recent progress in stem cell research has allowed the generation of RPE cells from human pluripotent cells, both embryonic stem cells (ESCs) and induced pluripotent stem cells (iPSC). Since iPSCs face neither ethical arguments nor significant immunological considerations when compared to ESCs, they open a new horizon for cell therapy of AMD. The current study aims to discuss AMD, review the protocols for making human iPSCs-derived RPEs, and summarize recent developments in the field of iPSC-derived RPEs cell therapy.