Insights and future directions for the application of perinatal derivatives in eye diseases: A critical review of preclinical and clinical studies.

Perinatal derivatives (PnD) are gaining interest as a source for cell-based therapies. Since the eye is easily accessible to local administration, eye diseases may be excellent candidates to evaluate novel therapeutic approaches. With this work, we performed a systematic review of published preclinical and clinical studies addressing PnD in the treatment of ocular diseases. We have set two specific objectives: (i) to investigate the current level of standardization in applied technical procedures in preclinical studies and (ii) to assess clinical efficacy in clinical trials. Hereto, we selected studies that applied amniotic membrane (hAM) and mesenchymal stromal cells derived from amniotic membrane (hAMSC), placenta (hPMSC), umbilical cord (hUC-MSC) and Wharton's Jelly (hUC-WJ-MSC), excluding those where cells were not transplanted individually, following a systematic PubMed search for preclinical studies and consultation of clinical studies on https://clinicaltrials.gov and https://www.clinicaltrialsregister.eu/. Our bibliographic search retrieved 26 pre-clinical studies and 27 clinical trials. There was a considerable overlap regarding targeted ocular structures. Another common feature is the marked tendency towards (i) locally administered treatments and (ii) the PnD type. In the cornea/ocular surface, hAM was preferred and usually applied directly covering the ocular surface. For neuroretinal disorders, intra-ocular injection of umbilical or placental-derived cells was preferred. In general, basic research reported favourable outcomes. However, due to lack of standardization between different studies, until now there is no clear consensus regarding the fate of administered PnD or their mode of action. This might be accountable for the low index of clinical translation. Regarding clinical trials, only a minority provided results and a considerable proportion is in "unknown status". Nevertheless, from the limited clinical evidence available, hAM proved beneficial in the symptomatic relief of bullous keratopathy, treating dry eye disease and preventing glaucoma drainage device tube exposure. Regarding neuroretinal diseases, application of Wharton's Jelly MSC seems to become a promising future approach. In conclusion, PnD-based therapies seem to be beneficial in the treatment of several ocular diseases. However, much is yet to be done both in the pre-clinical and in the clinical setting before they can be included in the daily ophthalmic practice

Phase 2 randomized, double-masked, vehicle-controlled trial of recombinant human nerve growth factor for neurotrophic keratitis

Purpose: To evaluate the safety and efficacy of topical recombinant human nerve growth factor (rhNGF) for treating moderate-to-severe neurotrophic keratitis (NK), a rare degenerative corneal disease resulting from impaired corneal innervation. Design: Phase 2 multicenter, randomized, double-masked, vehicle-controlled trial. Participants: Patients with stage 2 (moderate) or stage 3 (severe) NK in 1 eye. Methods: The REPARO phase 2 study assessed safety and efficacy in 156 patients randomized 1:1:1 to rhNGF 10 μg/ml, 20 μg/ml, or vehicle. Treatment was administered 6 drops per day for 8 weeks. Patients then entered a 48- or 56-week follow-up period. Safety was assessed in all patients who received study treatment, whereas efficacy was by intention to treat. Main Outcome Measures: Corneal healing (defined as <0.5-mm maximum diameter of fluorescein staining in the lesion area) was assessed by masked central readers at week 4 (primary efficacy end point) and week 8 (key secondary end point) of controlled treatment. Corneal healing was reassessed post hoc by masked central readers using a more conservative measure (0-mm staining in the lesion area and no other persistent staining). Results: At week 4 (primary end point), 19.6% of vehicle-treated patients achieved corneal healing (<0.5-mm lesion staining) versus 54.9% receiving rhNGF 10 μg/ml (+35.3%; 97.06% confidence interval [CI], 15.88–54.71; P < 0.001) and 58.0% receiving rhNGF 20 μg/ml (+38.4%; 97.06% CI, 18.96–57.83; P < 0.001). At week 8 (key secondary end point), 43.1% of vehicle-treated patients achieved less than 0.5-mm lesion staining versus 74.5% receiving rhNGF 10 μg/ml (+31.4%; 97.06% CI, 11.25–51.49; P = 0.001) and 74.0% receiving rhNGF 20 μg/ml (+30.9%; 97.06% CI, 10.60–51.13; P = 0.002). Post hoc analysis of corneal healing by the more conservative measure (0-mm lesion staining and no other persistent staining) maintained statistically significant differences between rhNGF and vehicle at weeks 4 and 8. More than 96% of patients who healed after controlled rhNGF treatment remained recurrence free during follow-up. Treatment with rhNGF was well tolerated; adverse effects were mostly local, mild, and transient. Conclusions: Topical rhNGF is safe and more effective than vehicle in promoting healing of moderate-to-severe NK

Phase I trial of recombinant human nerve growth factor for neurotrophic keratitis

Neurotrophic keratitis/keratopathy (NK), a rare degenerative corneal disease, lacks effective pharmacologic therapies.1 Because NK pathology involves trigeminal nerve damage and loss of corneal innervation, nerve growth factor (NGF) is surmised to promote healing of NK.2 Preliminary studies with murine NGF demonstrated efficacy for treating corneal neurotrophic ulcers;3 however, the complex tertiary structure of NGF has complicated the production of recombinant human NGF (rhNGF) suitable for clinical development. To this end, we developed an Escherichia coli–derived rhNGF formulation that demonstrated to be well tolerated and safe for topical ophthalmic use in a phase I study in healthy volunteers.4 We report phase I results of topical rhNGF for patients with moderate-to-severe NK

Caracterização do componente vascular da barreira hemato-retiniana: Estudos de microperfusão de arteríolas retinianas em coelhos normais e diabéticos

A Barreira Hemato-Retiniana (BHR) está localizada em 2 níveis - o epitélio pigmentado da retina e as células endoteliais dos vasos da retina, constituindo as chamadas Barreira Hemato-Retiniana Interna e Barreira Hemato-Retiniana Externa. Se bem que estas duas barreiras apresentem características comuns, os seus pormenores morfológicos, bioquímicos e, em suma, as suas funções são bem diferentes. Grande parte dos trabalhos estudando a permeabilidade e os mecanismos de transporte através da BHR referem-se, geralmente, à BHR como um todo, incluindo a externa e a interna, pouco se sabendo acerca da contribuição relativa de cada um dos seus componentes. Desenvolvemos um modelo experimental novo que nos permite estudar directamente in vitro a permeabilidade do componente vascular da Barreira Hemato-Retiniana quer em condições normais quer na diabetes experimental, através da utilização de técnicas de microperfusão adaptadas de estudos em túbulos renais, nas quais procedemos a ligeiras modificações. A aplicação desta metodologia à fisiologia vascular tem sido limitada em virtude, fundamentalmente, de problemas anatómicos relacionados com a dificuldade de isolamento de pequenos segmentos vasculares. Os vasos retinianos do coelho parecem ser particularmente apropriados para este tipo de estudo pois assentam directamente sobre a camada de fibras nervosas da retina, estando as suas paredes completamente livres de tecido glial em seu redor e em contacto directo com o vítreo, tornando possível a sua dissecção manual. Assim demonstrámos: 1 - A existência de um movimento uni-direccional de fluoresceína através dos vasos da retina, de fora para dentro do seu lúmen, aparentemente devido a um processo mais geral de transporte activo de aniões orgânicos; 2 - A existência de um fluxo de fluido de fora dos vasos para o seu lúmen; 3 - A dependência do fluxo de fluido em relação à fluoresceína e possivelmente em relação ao sistema mais geral de transporte de aniões orgânicos. Este fluxo de fluido também é dependente da temperatura; 4 - O transporte activo de fluoresceína aparece diminuído nas arteríolas de animais diabéticos, indicando uma alteração da permeabilidade nas suas paredes; 5 - A existência de um transporte de D-glicose do lúmen dos vasos retinianos para o banho, saturável e parcialmente inibido pela floretina; 6 - O fluxo de D-glicose, do lúmen dos vasos para o banho, encontra-se significativamente aumentado em arteríolas diabéticas e a floretina deixa de exercer uma acção inibitória. Este modelo experimental de microperfusão de segmentos vasculares da retina desenvolvido por nós, abre pois perspectivas extremamente interessantes na investigação da fisiologia e farmacologia dos vasos da retina, quer em situações normais quer em situações patológicas experimentais, bem como na manipulação farmacológica da retinopatia diabética

Caracterização do componente vascular da barreira hemato-retiniana: Estudos de microperfusão de arteríolas retinianas em coelhos normais e diabéticos

A Barreira Hemato-Retiniana (BHR) está localizada em 2 níveis - o epitélio pigmentado da retina e as células endoteliais dos vasos da retina, constituindo as chamadas Barreira Hemato-Retiniana Interna e Barreira Hemato-Retiniana Externa. Se bem que estas duas barreiras apresentem características comuns, os seus pormenores morfológicos, bioquímicos e, em suma, as suas funções são bem diferentes. Grande parte dos trabalhos estudando a permeabilidade e os mecanismos de transporte através da BHR referem-se, geralmente, à BHR como um todo, incluindo a externa e a interna, pouco se sabendo acerca da contribuição relativa de cada um dos seus componentes. Desenvolvemos um modelo experimental novo que nos permite estudar directamente in vitro a permeabilidade do componente vascular da Barreira Hemato-Retiniana quer em condições normais quer na diabetes experimental, através da utilização de técnicas de microperfusão adaptadas de estudos em túbulos renais, nas quais procedemos a ligeiras modificações. A aplicação desta metodologia à fisiologia vascular tem sido limitada em virtude, fundamentalmente, de problemas anatómicos relacionados com a dificuldade de isolamento de pequenos segmentos vasculares. Os vasos retinianos do coelho parecem ser particularmente apropriados para este tipo de estudo pois assentam directamente sobre a camada de fibras nervosas da retina, estando as suas paredes completamente livres de tecido glial em seu redor e em contacto directo com o vítreo, tornando possível a sua dissecção manual. Assim demonstrámos: 1 - A existência de um movimento uni-direccional de fluoresceína através dos vasos da retina, de fora para dentro do seu lúmen, aparentemente devido a um processo mais geral de transporte activo de aniões orgânicos; 2 - A existência de um fluxo de fluido de fora dos vasos para o seu lúmen; 3 - A dependência do fluxo de fluido em relação à fluoresceína e possivelmente em relação ao sistema mais geral de transporte de aniões orgânicos. Este fluxo de fluido também é dependente da temperatura; 4 - O transporte activo de fluoresceína aparece diminuído nas arteríolas de animais diabéticos, indicando uma alteração da permeabilidade nas suas paredes; 5 - A existência de um transporte de D-glicose do lúmen dos vasos retinianos para o banho, saturável e parcialmente inibido pela floretina; 6 - O fluxo de D-glicose, do lúmen dos vasos para o banho, encontra-se significativamente aumentado em arteríolas diabéticas e a floretina deixa de exercer uma acção inibitória. Este modelo experimental de microperfusão de segmentos vasculares da retina desenvolvido por nós, abre pois perspectivas extremamente interessantes na investigação da fisiologia e farmacologia dos vasos da retina, quer em situações normais quer em situações patológicas experimentais, bem como na manipulação farmacológica da retinopatia diabética

Surgical Approaches to Optic Disc Pit Maculopathy: A Clinical Case Series

The purpose of this study was to compare the clinical outcomes of 13 patients with optic disc pit maculopathy (ODP-M) – progressive visual loss, serous macular detachment, and/or intraretinal fluid – who underwent different surgical approaches. This was a retrospective study including a consecutive sample of 13 patients aged 13–74 years (mean 35.38 ± 19.66 years) diagnosed with ODP-M and submitted to vitreoretinal surgery between 2005 and 2021. All patients underwent pars plana vitrectomy, posterior hyaloid detachment, and gas tamponade. Endolaser photocoagulation was applied to the temporal margin of the optic disc in 8 cases; internal limiting membrane (ILM) peeling was performed in 9 cases; and ILM inverted flap technique in 5 cases. Stuffing of the pit with an ILM flap was performed in 3 cases. Mean best-corrected visual acuity improved from 20/200 (1.04 ± 0.56 LogMAR) to 20/50 (0.43 ± 0.54 LogMAR) within 4–36 months. Central retinal thickness decreased from 587.5 ± 158.01 μm to 253.9 ± 33.55 μm, and 7 out of 10 patients had complete resolution of intraretinal fluid. All patients had complete retinal reattachment; however, a few years after surgery, 4 patients had recurrence of serous retinal detachment. The only adjunctive technique associated with greater visual improvement was endolaser (p = 0.033) and not performing peeling of the ILM was also associated with better visual results (p = 0.013), independently of preoperative visual acuity or age at the time of surgery. None of the adjunctive procedures was a significant predictor of better anatomical outcomes. In conclusion, all of these approaches for the surgical management of ODP-M were safe and effective. In this study, vitrectomy with endolaser was a good option for management of ODP-M

Development of the Portuguese version of a standardized reading test: the Radner-Coimbra Charts

ABSTRACT Purpose: To develop 27 short sentence optotypes for the Portuguese version of the Radner Reading Charts. Methods: Thirty-four Portuguese sentences were constructed following the concept of the Radner Reading Charts to obtain highly comparable sentences in terms of lexical difficulty, syntactical complexity, word length, number of syllables, and position of words. A long text (106 words) at the 5th grade reading level was also tested to assess the validity of the reading speeds obtained with the short sentences. The short sentences and long text were tested in 50 volunteers with similar educational backgrounds (mean age 30.98 years ± 6.99 years, range 19-47 years). Reading speeds were measured with a stop-watch and reported as words per minute (wpm). The reading time for each of the short sentences to be selected for the chart was defined as falling within the range of the mean ± 0.40 × standard deviation (SD). Results: The overall mean reading speed for each of the short sentences was 235.43 ± 36.39 wpm. The 27 sentences with a mean between 220.8 and 250.0 wpm (overall mean ± 0.40 × SD) were selected for construction of the reading charts. The mean reading speed for the long text was 212.42 ± 26.20 wpm. Correlation between the selected short sentences and long text was high (r =0.86). Reliability analysis yielded an overall Cronbach's alpha coefficient of 0.97. Conclusions: The 27 short Portuguese sentences were highly comparable in terms of syntactical structure, number, position and length of words, lexical difficulty, and reading length. This reading test can overcome the limitations of the current tests for homogeneity and comparability, reducing subjectivity in the evaluation of the functional outcomes of medical and surgical ophthalmologic treatments.</div

Development of the Portuguese version of a standardized reading test: the Radner-Coimbra Charts

Purpose: To develop 27 short sentence optotypes for the Portuguese version of the Radner Reading Charts. Methods: Thirty-four Portuguese sentences were constructed following the concept of the Radner Reading Charts to obtain highly comparable sentences in terms of lexical difficulty, syntactical complexity, word length, number of syllables, and position of words. A long text (106 words) at the 5th grade reading level was also tested to assess the validity of the reading speeds obtained with the short sentences. The short sentences and long text were tested in 50 volunteers with similar educational backgrounds (mean age 30.98 years ± 6.99 years, range 19-47 years). Reading speeds were measured with a stop-watch and reported as words per minute (wpm). The reading time for each of the short sentences to be selected for the chart was defined as falling within the range of the mean ± 0.40 × standard deviation (SD). Results: The overall mean reading speed for each of the short sentences was 235.43 ± 36.39 wpm. The 27 sentences with a mean between 220.8 and 250.0 wpm (overall mean ± 0.40 × SD) were selected for construction of the reading charts. The mean reading speed for the long text was 212.42 ± 26.20 wpm. Correlation between the selected short sentences and long text was high (r =0.86). Reliability analysis yielded an overall Cronbach’s alpha coefficient of 0.97. Conclusions: The 27 short Portuguese sentences were highly comparable in terms of syntactical structure, number, position and length of words, lexical difficulty, and reading length. This reading test can overcome the limitations of the current tests for homogeneity and comparability, reducing subjectivity in the evaluation of the functional outcomes of medical and surgical ophthalmologic treatments.Objetivo: Desenvolver 27 frases-optotipo para a versão em português das tabelas de leitura de Radner. Métodos: Trinta e quatro frases em português foram elaboradas de acordo com o conceito das tabelas de leitura de Radner, de forma a obter frases-optotipo, altamente comparáveis em termos dificuldade lexical, complexidade sintática, tamanho das palavras, número de sílabas e posição das palavras. Foi também avaliado um texto longo (106 palavras) ao nível do 5o ano de escolaridade para determinar a validade dos resultados obtidos com as frases curtas. As frases curtas e o texto longo foram testados em 50 voluntários de nível acadêmico semelhante e média de idades de 30,98 anos ± 6,99 (intervalo de 19-47 anos). A velociade de leitura foi medida com cronômetro, de forma a obter o número de palavras por minuto (wpm). O intervalo válido para tempo de leitura das frases curtas foi definido como a média ± 0,40 x desvio padrão (SD). As frases mais semellhantes foram estatisticamente selecionadas para a construção das tabelas de leitura Radner-Coimbra. Resultados: A velocidade média de leitura obtida com as frases curtas foi 235,43 ± 36,39 wpm. As frases com velocidade média entre 220,8 e 250,0 palavras por minuto (média ± 0,40 x SD) foram selecionadas. Vinte e sete frases cumpriram este critério. A velocidade média de leitura do texto longo foi 212,42 ± 26,20 wpm. A correlação entre as frases curtas selecionadas e o texto longo foi alta (r=0,86). A análise de fiabilidade originou um coeficiente alfa de Cronbach de 0,97. Conclusões: As 27 frases em português são altamente semelhantes em termos de estrutura sintática, número, posição e comprimento das palavras, dificuldade lexical e duração da leitura. Este teste permite ultrapassar as limitações dos testes existentes em termos de homogeneidade e comparabilidade, reduzindo a subjetividade na avaliação dos resultados de terapêuticas médicas e cirúrgicas

Characterization of the Portuguese population diagnosed with retinoblastoma

The purpose of this study is to characterize demographically and genetically the Portuguese population with retinoblastoma; to report the clinical stage at presentation and its impact on survival and ocular preservation rate and, finally, to assess the incidence of retinoblastoma in Portugal. Retrospective observational study including children consecutively diagnosed with retinoblastoma at the Portuguese National Referral Center of Intraocular Tumors, between October 2015 and October 2020. Twenty-eight children were diagnosed with retinoblastoma at our center, 15 hereditary from which 12 presented with bilateral retinoblastoma and 3 were unilateral. The overall mean age at diagnosis was 13.6 ± 11.1 months with hereditary retinoblastomas diagnosed slightly earlier at 9.6 ± 6.3 months. A familial history of retinoblastoma was found in only 4 (14.3%) of the cases. A pathogenic mutation in the RB1 gene was found in 13 (46.4%) of the children. The most frequent sign at referral was leukocoria in 71.4% of patients. Considering the ICRB classification of the tumors, 84.6% of non-hereditable hereditary retinoblastomas were referred to our center in advanced stages. In the group of hereditable retinoblastomas 86.7% presented with one of the eyes with advanced intraocular retinoblastoma. Fourteen children had one eye enucleated due to retinoblastoma. No deaths were registered during the study period. Considering the incidence analysis, we registered a year-of-birth controlled incidence analysis of 4.04 per 100.000 living births (IC 95% 1.59-6.49). This is the first characterization of the Portuguese Population diagnosed with Retinoblastoma in the National Reference Center