RCAAP Repository

A 61-year-old man presented with a superior visu- al field defect on his right eye (RE), for 3 months, but he delayed coming to the emergency department for fear of coronavirus. His best-corrected visual acuity of the RE was 1.25/10 and biomicroscopy generated unremarkable findings. A large, dome-shaped, pigmented, and peripheral lesion with an adjacent exsudative retinal detachment was seen on ophthalmoscopy and documented by an ultra-wide field pseudocolor photograph captured using Optos (Fig. 1). B-scan ultrasonography confirms a low-moderate internally reflective dome-shaped choroidal lesion, sized 13x12 mm, with adjacent retinal detachment. The optical coherence tomography of the macula showed subretinal fluid reaching the fovea. Patients are avoiding medical care due to fear of coronavirus.1 Regarding choroidal melanoma, patients will present with more advanced disease with lost opportunities for conserving vision and the eye.2 We want to alert to this new reality that we have been facing and the need to provide health literacy, avoiding unnecessary costs for patients, and conserve healthcare resources.

Introdução: Nosso objetivo é relatar um caso de paralisia traumática grave do VI par bilateral. Descrevemos um caso clínico documentado com fotografias em diferentes posições do olhar; gráficos do ecrã de Hess e testes de campo visual de Goldmann durente o período de seguimento. Relato de caso: Um homem de 42 anos envolveu-se num acidente de carro de alta energia (240 km/h). Nove dias depois, quando foi transferido para nosso hospital, apresentou quadro de paralisia grave do sexto nervo bilateral, com limitação na abdução do olho direito e esquerdo, sem cruzar a linha média. Ele foi submetido a 3 injeções de toxina botulínica do reto medial (BTX). O primeiro feito 1 mês e as últimas 6 meses após o acidente. O doente obteve bons resultados sem diplopia e sem limitações de abdução. Conclusão: Embora o envolvimento bilateral e a gravidade do déficit de abdução na paralisia do VI par estejam independentemente associados a um mau prognóstico, o caso clínico apresentado obteve um bom desfecho com recuperação total e definitiva da paralisia bilateral grave após injeções de BTX no reto medial iniciadas na fase aguda.

We describe a case of mycotic keratitis involving a rare fungus and review the literature on Rhodotorula keratitis. A 40-year-old man was struck in the right eye with a tree branch and developed a corneal ulcer involving the anterior portion of the cornea. Cultures grew Rhodotorula glutinis. The patient was initially treated with topical amphotericin, but only improved with topical and intracameral voriconazole administration. The corneal infiltrate resolved, leaving an anterior stromal scar, and the patient’s best-corrected visual acuity was 20/60 in the involved eye. Cases of Rhodotorula keratitis can pose a challenge to the ophthalmologist, with the diagnosis and the treatment regimen, as this yeast may not respond well to commercially available drugs. We report a case of Rhodotorula keratitis that was only resolved with voriconazole. Our case rein- forces the importance of the early diagnosis and correct management of fungal keratitis involving this rare, but potentially damaging yeast.

No summary/description provided

The purpose of this study was to report the case of a newborn with lipemia retinalis and the clinical evolution after treatment. RetCam fundus photographs were taken before and after treatment with exchange transfusion and fat restriction diet. A 1 month and 25 days old female with a history of 3 days irritability with bilateral leukocoria and a creamy pale blood sample was treated for primary hyperlipidemia. After treatment, symptoms resolved, leukocoria disappeared and fundus exam appearance became normal. Lipemia retinalis in the newborn can fully resolve with appropriate systemic treatment.

INTRODUCTION: The purpose of this study is to evaluate demographic features, risk factors, bacterial isolates, antibiotic resistance patterns and therapeutic approach of bacterial keratitis over a period of 10 years in a tertiary referral hospital in Lisbon. M E T HO D S : Retrospective review of all bacterial keratitis diagnosed between 2009 and 2019. RESULTS: A total of 350 patients were diagnosed with bacterial keratitis between 2009 and 2019. Mean age was 54.77 years and 55% of patients were female. Based on first clinical observation, 72.3% of patients were classified as having serious keratitis and 60.86% were managed as in-patients. Contact lenses were the major risk factor identified (30.3%), followed by previous keratoplasty (11.1%) and ocular trauma (10.9%). Cultures were positive for bacteria in 56.86% of patients, with gram-negative bacteria comprising more than half of the isolates (52.26%). Pseudomonas aeruginosa was the most common single isolate (16.3%). Monotherapy with fluoroquinolones was given to 5.7% of patients and 75.4% were treated with fortified drops of ceftazidime and vancomycin. As for outcomes, 41 patients (11.7%) were submitted to a corneal transplant and five patients were eviscerated. CONCLUSION: Bacterial keratitis is a potentially blinding condition that leads to a great number of emergency department visits and inpatient care. Over the last 10 years, Pseudomonas aeruginosa has been the single most common bacterial isolate and contact lens wear the most frequent risk factor for bacterial keratitis in our center. Identifying bacterial isolates and their resistance pattern is of utmost importance for optimal management of patients.

Mulher de 77 anos de idade, com antecedentes de HTA e diabetes mellitus tipo 2, recorreu ao serviço de urgência por queixas bilaterais de olho vermelho, desconforto ocular e cefaleias, com 1 semana de evolução, sem história de trauma. No exame oftalmológico, apresentava uma melhor AV corrigida de 20/32 à direita e 20/25 à esquerda. À inspeção, destacava-se a proptose bilateral e na biomicroscopia a hiperemia conjuntival, quemose discreta e a presença de vasos epibulbares tortuosos, com especto em “saca-rolhas”. A avaliação da motilidade ocular revelava uma limitação na abdução do OE, com diplopia na levoversão. A pressão intra-ocular estava elevada bilateralmente (29 mmHg OD e 34 mmHg OE). Fundoscopicamente, observava-se discreta tortuosidade venosa. O estudo complementar com TAC cerebral/órbitas e angio-TAC dos vasos cervicais e polígono de Willis revelava um espessamento difuso dos músculos extraoculares e preenchimento de ambos os seios cavernosos, com dilatação das veias oftálmicas superiores, confirmando o diagnóstico de fístula carótido-cavernosa dural esquerda, com drenagem anterógrada para a veia oftálmica superior direita e oclusão da veia oftálmica superior esquerda. A doente foi submetida a embolização endovascular com espiras, obtendo-se encerramento da fístula, com consequente ausência de preenchimento das estruturas venosas arterializadas e posterior resolução da sintomatologia.

Introduction: Our purpose was to evaluate the effect of eye rubbing discontinuation on the epithelial thickness profile by spectral-domain AS-OCT (anterior segment optical coherence tomography) in allergic children with no tomographic sign of corneal ectasia.   Methods: Right-handed boys (average age 11.2 years, 8-12 years) with history of eye rubbing and relatively normal Pentacam (Oculus; Wetzlar, Germany) exams were recruited for the study. Patients were evaluated using AS-OCT (Zeiss Cirrus 5000 HD-OCT, Carl Zeiss Meditec, Dublin, CA, USA) at the baseline and after 8 weeks of treatment. Treatment included education to avoid eye rubbing and preservative free 0.25 mg/mL topical ketotifen. Epithelial thickness (ET) and full corneal thickness (CT) parameters were compared with paired non-parametric Wilcoxon (signed-ranked) test.  A p-value lower than 0.05 was considered for statistical significance.   Results: Twenty-five boys completed the protocol. No eyes had tomographic criteria for keratoconus (Belin-Ambrosio Deviation Value < 1.22). Minimum epithelial location moved from the inferotemporal to superotemporal octant after treatment. The differences between minimum and maximum epithelial thickness (-2.8 µm vs -5.2 µm; p<0.01) and between nasal and temporal octants (N-T) (3.1 µm vs 1.4 µm; p<0.01) were higher at the baseline. The difference between inferior and superior (I-S) octants (1.1 µm vs 2.7 µm; p<0.01) was lower at the baseline.    Conclusion: AS-OCT analyses reveal epithelial remodeling after allergy treatment and eye rubbing discontinuation, with marked inferotemporal thickening. The importance of educating against eye rubbing and treating allergy should consider its importance on corneal epithelial remodeling. Further studies should include patients with corneal ectatic conditions and to explore other clinical measurements such as biomechanical assessment. 

Introdução: Descrição de um caso clínico respeitante a queratopatia estromal induzida pelo aumento da pressão intraocular (PISK) após facoemulsificação num doente previamente submetido a implante de anel intra-estromal por ectasia pós cirurgia refrativa. Descrição do caso: Doente do sexo masculino de 53 anos com história de ectasia pós LASIK no olho direito, foi submetido a facoemulsificação e implante de lente intraocular dois meses após implante de anel intraestromal. No primeiro dia pós-operatório, apresentava queixas de diminuição da acuidade visual.  A melhor acuidade visual corrigida (MAVC) para longe era 20/80, a pressão intraocular (PIO) era 55mmHg e a biomicroscopia revelou edema de córnea e a presença de haze difuso na interface. A tomografia de coerência ótica do segmento anterior (OCT-SA) confirmou a presença de líquido na interface. Os corticoesteróides foram suspensos e foi introduzida medicação anti-hipertensora. Uma semana após a cirurgia, a MAVC melhorou para 20/40, a córnea apresentava-se transparente e o OCT-SA revelou uma completa reabsorção do fluido. Conclusão: Embora a PISK normalmente se apresente no pós-operatório imediato de LASIK, pode ocorrer noutras situações clínicas associadas a elevação da PIO. O presente caso clínico realça a importância da profilaxia dos picos hipertensivos pós-operatórios em olhos com história de cirurgia que envolva a criação de uma interface na córnea, particularmente no que respeita ao uso de corticosteróides que parecem potenciar o desenvolvimento de PISK. 

Introduction: Central serous chorioretinopathy (CSC) is an idiopathic syndrome characterized by neurosensory detachments of the retina. Development of chronic CSC is an indication to treat, and ICGA-guided verteporfin photodynamic therapy has been shown to be very effective.   Our objective was to evaluate the 13-year follow-up of chronic CSC patients treated with standard-fluence PDT and to explore the long-term microstructural and vascular choroidal changes related to the disease and treatment. Methods: Retrospective, interventional case-series analysis was conducted on 18 patients with cCSC, treated with standard PDT. Evaluations were performed every 3 months in the first year, every 6 months during the second year, and annually thereafter. All participants underwent a comprehensive ophthalmic examination. Retinal and choroidal imaging was performed with SD-OCT, SS-OCT, Optomap and OCTA. Results: Twenty-three eyes of eighteen patients were included, with a mean age of 63.9±8.5 years. The mean follow-up was 15.8±1.4 years. The mean number of sPDT treatments was 1.2±0.4. At baseline, subretinal fluid was found in all eyes, RPE proliferation in 9.1% and atrophy in 9.1% of the eyes. There was not a statistically significant improvement in BCVA, despite an initial mean gain of 5.08±10.36 letters at month 12 (p<0.05), which decreased to 1.87±11.9 letters at the end of follow-up. In the final visit, only 3 eyes present subretinal fluid, 3 had fibrosis, but 15 (65.2%) showed atrophy. Central macular thickness reduced from 340.7±114.9 µm to 228.7±38.6 µm at end of the follow-up. The choroid of treated eyes was thicker but the choriocapillaris had less vascular flow compared to fellow-nontreated eyes at this point. Only one session of sPDT was needed in the 19 eyes, and 4 underwent 2 sessions.  Conclusion: ICGA-guided PDT full-fluence is a safe procedure, with no ocular or systemic adverse effects registered in our cohort. After 13 years, only 17.4% required 2 sessions. However, two-thirds of the cases presented atrophy in the last visit, which is probably related to the degenerative course of the disease and limited the initial visual acuity gains in the long term.

Introdução: Este estudo apresenta uma nova técnica cirúrgica transconjuntival minimamente invasiva para a fixação de lente intraocular (LIO) de câmara posterior de acrílico hidrofílico em 4 pontos distintos, na ausência de suporte capsular, através da utilização de fio de politetrafluoroetileno expandido (ePTFE, Gore-Tex®). Métodos: A técnica descrita foi utilizada em 26 olhos, sem suporte capsular, de 26 pacientes com um tempo mínimo de seguimento de 6 meses. Foram avaliadas as variáveis: idade, sexo, indicação para a cirurgia, pressão intraocular (PIO), acuidade visual corrigida para a distância (AVCC) antes e após a cirurgia, equivalente esférico (EE) pós-operatório, centragem e “tilt” da LIO, astigmatismo induzido cirurgicamente (AIC), procedimentos combinados, complicações intra e pós-operatórias e tempo de seguimento após a cirurgia. Resultados: A média de idade dos pacientes foi 77,62 ± 12,23 anos; o seguimento médio foi de 20,2 ± 9,30 meses. A AVCC melhorou após a cirurgia, de logMAR 0,43 ± 0,25 para 0,13 ± 0,08 (p = 0,010). Nenhum paciente perdeu linhas de acuidade visual na tabela de Snellen. A média do EE pós-operatório foi de -0,28 ± 0,26 dioptrias; a média do AIC de 0,24 ± 0,16 dioptrias foi obtida após incisão límbica de 2,0 ou 2,2 mm. Em cinco doentes com glaucoma prévio não controlado, foi realizada cirurgia de glaucoma simultânea. Como complicações pós-operatórias, observamos dois casos de hipertensão ocular (ambos em doentes com glaucoma prévio) e um caso (3,8%) de hemovítreo resolvido não cirurgicamente. Em nenhum caso foi observada pseudofacodonesis, descentramento ou “tilt” da LIO, captura óptica pupilar, dispersão de pigmento ou outras complicações pós-operatórias. Conclusão: Os resultados deste estudo demonstram que esta técnica representa um procedimento minimamente invasivo para a fixação escleral de lentes, que reduz significativamente a morbilidade associada a técnicas de suspensão escleral, aumentando a sua segurança e reprodutibilidade.

Introduction: Sector retinitis pigmentosa (sRP) is a rare, atypical, and milder variant of rod-cone degeneration. Despite historically associated with RHO gene, the mutational spectrum of sRP is evolving with multiple causative genes recently implicated. This study aimed to characterize the genotypes, phenotypes, and natural history of a Portuguese cohort of sRP.   Methods: Retrospective, observational study, conducted at a tertiary referral center. Patients with a clinical diagnosis of sRP and available genetic testing results were identified using a web-based registry. The clinical diagnosis was established based on ophthalmologic examination, functional testing [best corrected visual acuity (BCVA) and visual field testing] and multimodal imaging [color fundus photography (CFP), fundus autofluorescence (FAF) and optical coherence tomography (OCT)]. Genetic testing was clinically oriented in all probands, and variants were classified according to the American College of Medical Genetics and Genomics. Only likely pathogenic or pathogenic variants were considered disease-causing. Clinical progression was evaluated throughout follow-up. Results: Fourteen patients from twelve families were included. Disease-causing variants in RP-related genes were identified in 8 families, for a diagnostic yield of 66.7%. EYS was the most frequently implicated gene (4 families), followed by RHO (2 families), and finally MYO7A and NPHP1 (1 family each). In most unsolved cases, no clinically significant variants were found. However, for one unsolved case, a RHO-associated variant of uncertain significance was identified. Two patients exhibited syndromic sRP. All cases were bilateral and symmetrical except for two. Inferior and/or nasal retinal involvement on FAF was noted in all cases. Visual field testing revealed superior field defects of varying extents, always in close association with observed FAF findings. Over a median follow-up of 32.5 months (range: 5-148 months), no significant differences were found on BCVA (p=0.056). In fact, BCVA remained stable and ≤ 0.20 LogMAR OU in 9/14 patients. Multimodal imaging revealed no progression over the available follow-up. Conclusion: This study highlights the genotypic heterogeneity of sRP in a Portuguese cohort. Inferior and nasal predilection was common across different genotypes, and a high proportion of patients maintained good central vision. The longitudinal data provided herein will help to accurately inform patients on prognosis.

INTRODUCTION: Our purpose was to compare best corrected visual acuity (BCVA), endothelial cell density (ECD) and postoperative complications in adult patients with corneal endothelial disorders who were submitted to descemet stripping automated endothelial keratoplasty (DSAEK) or descemet membrane endothelial keratoplasty (DMEK). METHODS: Retrospective, single-centre, observational cohort study. Fifty one eyes from 51 patients with corneal endothelial disorders who were submitted to either a traditional DSAEK (n=23 patients) or a DMEK (n=28 patients) at Centro Hospitalar Universitário S. João (Porto, Portugal), and followed for at least one year after the procedure in our department were included. Patients without at least one ECD determination after transplantation and those who experienced primary graft failure were excluded. Patient demographics, BCVA with the logMAR scale before and one year after grafting, indication for transplantation, and postoperative complications were recorded. Specular microscopy with ECD determination (in cells/mm2) was performed on all donor corneas before grafting and regularly after transplantation, as part of our patient’s usual follow-up. RESULTS: Patients’ demographics, indications for transplantation and BCVA before graft- ing were similar in both groups. BCVA 1-year after transplantation was better in the DMEK group (0.26 ± 0.19 vs 0.47 ± 0.29 in the DSAEK group; p=0.003). ECD in donor corneas before grafting was similar in both groups (p=0.986). Graft ECD after transplantation was higher in the DMEK group at up to 5 months (p<0.001), 5 to 9 months (p=0.037) and 9 to 15 months follow-up (p=0.003), being similar in posterior determinations. 2 DMEK eyes required rebubblin. Two DSAEK eyes suffered graft rejection. CONCLUSION: In our cohort, DMEK presented better visual outcomes than DSAEK. The DMEK group showed higher mean ECD and lower ECD loss in the first 15 months of follow-up, but posterior measurements were similar in both groups. Therefore, both techniques had similar long-term mean ECD and ECD loss and other criteria should be used to determine which one is best suited for each case in our clinical practice.

Introduction Our purpose was to describe the molecular and multimodal retinal imaging findings in a cohort of Portuguese patients with a clinical diagnosis of Stargardt Disease (STGD1).   Methods Multicenter, cross sectional cohort study of consecutive patients with a clinical diagnosis of STGD1, referred from six Portuguese centers. All patients underwent a complete ophthalmological examination complemented by color fundus photography (CFP), fundus autofluorescence (FAF), optical coherence tomography (SD-OCT) and, when available, OCT-angiography (OCTA). Probands with confirmed molecular diagnosis, defined as presenting biallelic mutations classified as pathogenic or likely pathogenic in accordance with the guidelines of the American College of Medical Genetics and Genomics, were divided into three groups according their genotype’s severity.    Results The study included 122 eyes from 61 patients, 54 of which unrelated. Mean age of onset (AO) and mean disease duration were 16.64±12.87 and 20.04±15.21 years, respectively. Confirmed molecular diagnosis was obtained for 26/38 families with available genetic results (diagnostic yield of 68.42%), with the c.1804C>T (p.Arg602Trp) missense variant being the most prevalent (8/26). The less severe genotype group (Group C) was the most frequent (14/26), with a mean AO slightly superior, not statistically significant, to the other groups (B and A). The most frequent CFP pattern was central atrophy with macular and/or peripheral flecks (56 eyes), followed by multiple extensive atrophic changes (n=40). On FAF, 21.05% of the eyes showed a homogeneous background with localized central hypoAF (pattern 1), with the remaining distributing equally through patterns 2 (heterogeneous background of hypo/hyperAF foci and localized central hypoAF) and 3 (multiple areas of hypoAF in a heterogeneous background). Worse visual acuity significantly correlated with advanced CFP and FAF patterns (both p<0.001), reduced central macular thickness (p=0.017), larger foveal avascular zone (p<0.001), reduced density of the superficial (p<0.001) and deep capillary plexuses (p=0.017), and increased area of choriocapillaris atrophy (p=0.007).   Conclusion This study describes the phenotypic and genotypic spectrum of STGD1 in a multicenter Portuguese cohort, revealing a satisfactory detection rate of disease-causing genotypes. The qualitative and quantitative imaging features presented a strong correlation with visual acuity and disease progression and may represent important outcome measures in the evaluation of new therapeutic targets. 

INTRODUCTION: Traditionally, the goal of strabismus treatment has been to realign the visual axes in order to eliminate diplopia, to produce, maintain, or restore binocular vision or for aesthetic reasons. Nowadays, surgery to improve an abnormal head position (AHP) is also a well-accepted indication for surgery. AHP or torticollis is a frequent encountered sign in routine ophthalmology practice, especially in pediatric patients. The present study aims to characterize the patients of a tertiary hospital who were submitted to surgery for an AHP caused by an ocular condition, as well as the results obtained by the treatment provided to them. MATERIAL ANd METHODS: The medical records of patients who were admitted to surgery for an AHP in the Ophthalmology department of Centro Hospitalar Universitário de São João between July 2014 and July 2021 were retrospectively studied. The patients underwent ophthalmologic examinations pre and post-operatively. Characterization of the AHP was subjectively evaluated. RESULTS: In total, 24 patients were studied, 8 (33.3%) of whom were female and 16 (66.6%) were male. Mean age of patients was 13.7 years (range 3-61 years). There were 7 patients with superior oblique palsy, 7 patients with Duane syndrome (type 1), 6 patients with nystagmus, 3 patients with third nerve paralysis and 1 patient with Brown syndrome. Face turn was the most frequent AHP (14 patients), followed by head tilt AHP (5 patients). Four patients had mixed AHP (head tilt and face turn) and 1 patient presented with chin up. A total of 95.8% of patients had their AHP improved with surgical treatment. Nineteen patients were submitted to one surgery and a second surgery was necessary in 5 patients. CONCLUSION: Overall, almost all patients improved after surgery. Nevertheless, it is important to highlight that occasionally it is necessary more than one surgery to achieve the best result,

No summary/description provided

INTRODUCTION : Our purpose was to compare changes in biomechanical properties after Artiflex® and Visian® ICLV4c implantation. METHODS: A prospective, nonrandomized, comparative, interventional case series study with corneal biomechanical evaluation by an ultra-high-speed Scheimpflug imaging during non-contact tonometry (Corvis ST, OCULUS®). RESULTS: The study included 38 eyes: 23 Artiflex-treated eyes and 15 implantable collamer lens (ICL)-treated eyes. The average age at surgery and the mean follow-up time were similar between groups (p=0.170 and p=0.252, respectively). Artiflex- and ICL-treated eyes showed a significantly stiffer behaviour in 12/28 and 4/28 of first and in 5/11 and 1/11 of second generation biomechanical corneal parameters compared to preoperative values, respectively. Both groupsshowed a softer behaviour in the same only 2/28 of first generation parameters. Comparing Artiflex- and ICL-treated eyes, the “PachySlope” was the only postoperative parameter that differed between groups, but the difference already exists in preoperative evaluation. All biomechanical parameters had a similar or less proportion of eyes within ectasia susceptibility interval at post-operative in both Artiflex- and ICL-treated eyes. There was a significant increase of intraocular pressure (evaluated by different methods, all with p<0.05) in Artiflex-treated eyes after surgery, compared to preoperative values. CONCLUSION: Overall it seems that there is an increase in corneal resistance after both phakic intraocular lens implantation (supported by less proportion of eyes within ectasia susceptibility interval at postoperative) or in aqueous humour resistance. The effect seems to be higher in Artiflex-treated eyes because of more postoperative biomechanical parameters changed and higher IOP (evaluated by different methods) than ICL-treated eyes, when comparing the pre and postoperative period. These findings support the safety of these surgical options for the correction of the refractive error of eyes with contraindications to laser ablation from a biomechanical viewpoint.

This work reports a case of Prader-Willi syndrome, with dyschromatopsia, its clinical characteristics and ophthalmological changes, monitoring and treatment, in a 6-year-old child. Prader-Willi syndrome is rare, being an autosomal dominant disorder caused by the exclusion of the proximal long arm of the paternal chromosome 15 (15q11-q13) or inheritance of both pairs of chromosomes 15 from the mother. Clinical manifestations include mental retardation; muscle hypotonia; hyperphagia; obesity; low; hypogonadism; strabismus; and hypersomnolence. Ophthalmological manifestations included: almond-shaped eyes, a characteristic of the syndrome, convergent strabismus, hyperopia and a dyschromatopsia. Prescribed optical correction and orthoptic treatment with occlusion and improvement of ocular deviation. After an extensive review of the literature, we found no reference to other cases of dyschromatopsia related to Prader-Willi syndrome. It evidenced the need for revision in the administration of the Brazilian public health system, highlighting the long itinerary for diagnosis and treatment covered by the patient. as well as the possibility of being assisted by telemedicine.

INTRODUCTION: Keratoconus (KC) is a corneal ectatic disorder characterized by pro- gressive corneal thinning and steepening. Corneal collagen cross-linking (CXL) uses riboflavin and ultraviolet-A radiation to induce cross-links in the stromal collagen, increasing its biomechanical rigidity and halting the progression of KC. Different protocols of CXL have been proposed throughout the years to improve clinical results and patient comfort. However, management of pediatric cases remains particularly challenging because younger patients tend to exhibit a more rapid progression of the disease. In this study we aim to evaluate the efficacy of CXL in a population of pediatric patients aged 18 years or less with progressive KC. MATERIAL AND METHODS: Multi-center, retrospective, cross-sectional study. Patients with progressive KC, aged ≤ 18, who underwent CXL between 2010 and 2021 were reviewed. Different modalities of CXL were used: Standard CXL, Accelerated CXL, Combined CXL and partial topography-guided PRK (photorefractive keratectomy), and Customized CXL. Evaluation included best spectacle corrected visual acuity (BSCVA), manifest refraction, and Scheimpflugtomography evaluation. Baseline and follow-up values were compared. RESULTS AND DISCUSSION: The study included 44 eyes of 33 patients, 26 (78.8%) male and 7 (21.2%) female. Mean age at time of CXL was 15.2±3.1 years [range 10-18]. Convention- al CXL was performed in 9 eyes, and accelerated CXL in 14 eyes. Seven eyes performed combined CXL and simultaneous topography guided PRK. Fourteen eyes performed customized irradiation CXL. Epithelium was removed before CXL in all patients. Mean follow-up was 21.9±16.6 months [range 4-66]. At the last follow-up, mean BSCVA was improved from 0.43±0.26 to 0.38±0.25 Log- MAR (p=0.067). Preoperative mean spherical equivalent increased from -1.97±2.44 to -2.41±3.60 D (p=0.509) and cylinder decreased from 2.85±1.92 to 2.34±1.77 D (p=0.045). The flat keratometric values (K1) remained stable, from 48.04±4.87 to 48.74±5.12 D (p=0.358), as well as the steep keratometric values (K2), from 53.63±6.60 to 53.98±6.09 D (p=0.721), and maximum keratometry values (K max), from 62.45±10.38 to 62.20±10.01 D (p=0.764). Thinnest corneal thickness decreased from 452.03±39.63 to 423.59±43.17 μm (p<0.001). Mean spherical equivalent increased in conventional CXL eyes, and had a greater decrease in those having undergone combined CXL and PRK (p=0.042). Thinnest corneal thickness decreased more significantly in the combined CXL and PRK eyes (p<0.001). No other differences between different CXL protocols were significant. Success rate at the last follow-up was 90.9%, with 4 eyes (9.1%) showing progression after CXL: 2 following accelerated CXL and 2 following customized irradiation CXL. CONCLUSION: CXL seems to halt the progression of KC in pediatric patients and result in stabilization of visual acuity and topographic parameters. Our results are in line with the published international series for pediatric KC, showing overall good results but more risk of progression than adult patients. Alternative protocols seem to be equally effective as standard-CXL in pediatric KC.