Bilateral interstitial keratitis following COVID-19: a case report.

BACKGROUND: Although the primary target of severe acute respiratory syndrome coronavirus 2 is the respiratory tract, the expression of the angiotensin-converting enzyme 2 receptor in other tissues facilitates viral entry in others parts of the body, including ocular structures. Ocular manifestations may occur before, during, or after systemic infection. CASE PRESENTATION: We report the case of a 60-year-old male who presented with bilateral interstitial keratitis after the onset of COVID-19, with ocular symptoms starting within 7 days after systemic symptoms. Laboratory investigation did not identify any alternative etiology for his disease, although the possibility of Epstein-Barr virus or herpes simpex virus could not be definitively ruled out. The patient had already developed significant corneal scarring and visual debilitation by the time topical steroids were initiated, and his final corrected visual acuity with rigid gas permeable contact lenses was 20/50 and 20/80 in the right and left eye, respectively. CONCLUSIONS: The involvement of ocular tissue by the virus can lead to permanent sequelae such as severe visual loss, and clinicians should be aware of and recognize ophthalmic manifestations of this disease to prompt early intervention.

Correlations of Immediate Corneal Tomography Changes with Preoperative and the Elapsed Phaco Parameters.

Purpose: The ability to predict corneal edema and understand its relationship with imaging parameters enables optimization of decision-making in terms of cataract surgery. Therefore, we aimed to elucidate the immediate tomographic alterations after phacoemulsification. Patients and Methods: In this prospective study, we evaluated clinical and corneal tomographic data of 30 patients with cataracts, obtained using a rotating Scheimpflug tomographic system before and after cataract surgery with a phacoemulsification system. Corneal thickness and volume were measured, and Pentacam Nucleus Staging, keratometry, and specular microscopy were performed preoperatively and immediately postoperatively. The Wilcoxon signed-rank test was used to compare pre-and postoperative values. We calculated the correlations between the changes in these values and multiple parameters related to phacodynamics, including "ultrasound (US) elapsed" (phaco time), "US average" (average power used), and "US absolute" (energy effectively dissipated, a product of the other two parameters). Results: There were increases in corneal volume (p<0.0001) and pachymetry (p<0.0001), and a decrease in endothelial cell count (p<0.0001) after surgery. The mean differences in pre- and postoperative specular microscopy, corneal volume, and pachymetry were -335.13±236.21 cells/mm3, 1.33±0.56 mm3, and 61.33±23.73 microns, respectively. The difference in pre-and postoperative corneal volume in patients with US elapsed ≥40 s was 0.75 mm3 greater than that in patients with US elapsed <40 s (95% confidence interval [CI]: 0.24-1.25; p=0.005); that of pachymetry in patients with US elapsed ≥40 s was 31.76 microns greater than that in patients with US elapsed <40 s (95% CI: 9.55-53.97; p=0.007). Spearman correlation revealed that, for every 1% increase in cataract density, the US average value increased by 0.31% (coef.: 0.3110; 95% CI: 0.0741-0.5490; p=0.012). Conclusion: Knowledge of Pentacam Nucleus Staging and the effect of US elapsed on differences in corneal volume and pachymetry before and after cataract surgery should be of particular value for surgeons who routinely encounter patients with hard cataracts.

Comparação entre os resultados do implante de um segmento de arco longo versus dois segmentos de arco tradicional no tratamento de pacientes com ceratocone / Comparison between the results of implanting a long-arch segment versus two standard arch segments for treatment of keratoconus patients

RESUMO Objetivo: Analisar retrospectivamente as alterações na ceratometria e no astigmatismo corneano obtidas após cirurgia de implante de anel intraestromal, comparando o uso de um segmento de arco longo versus o implante de dois segmentos de comprimento de arco tradicional. Métodos: A partir de um estudo transversal, obtivemos os dados de 94 olhos de pacientes diagnosticados com ceratocone, que foram submetidos ao implante de anel corneano. Eles foram divididos em dois grupos, dependendo do tipo de implante recebido: Grupo A, um segmento de arco longo; Grupo B, dois segmentos tradicionais. Todos os segmentos implantados possuíam 250µ de espessura. Os dados do pré-operatório dos dois grupos foram comparados, para garantir que as amostras eram similares (as diferenças encontradas entre os dois grupos não eram estatisticamente significativas). As variáveis analisadas no pré e no pós-operatório foram acuidade visual com correção, ceratometria, astigmatismo corneano e refração. Resultados: A amostra que recebeu apenas um segmento de arco longo (Grupo A) obteve redução da ceratometria média de 4,42D (8,7%) e do astigmatismo corneano de 2,43D (40,4%). Já na amostra dos olhos que receberam dois segmentos de arco tradicional (Grupo B), houve redução média de 2,66D (5,1%) em relação à ceratometria média e redução média de 2,11D (34,8%) em relação ao astigmatismo corneano. A redução obtida na ceratometria média no Grupo A foi maior que a obtida no Grupo B (diferença estatisticamente significativa). A redução obtida no astigmatismo do Grupo A não foi estatisticamente significante, se comparada com o resultado obtido no Grupo B (considerando p≤0,05). Conclusão: Foi demonstrado que o uso de um segmento de arco longo possui maior capacidade de aplanação corneana, se comparado com o uso de dois segmentos com comprimento de arco tradicional. Em relação à redução do astigmatismo, os dois grupos mostraram resultados equivalentes.

ABSTRACT Purpose: To retrospectively analyze the changes in corneal keratometry and astigmatism after intrastromal ring surgery, comparing the use of one long arch segment versus two traditional arc length segments. Methods: A cross-sectional study obtained data from 94 eyes of patients diagnosed with keratoconus that underwent surgical treatment with corneal ring implant. They were divided into two groups according to the type of implant received: one long-arch segment (Group A) or two traditional segments (Group B), both 250 microns thick. Preoperative data from the two groups were compared to ensure that the samples were similar (the differences between the two groups were not statistically significant). The variables (pre and post-operatively) analyzed were: best corrected visual acuity, keratometry, corneal astigmatism and refraction. Results: Group A, which received one long arch segment, showed a Km decrease of 4.42D (8.7%) and a corneal astigmatism reduction of 2.43D (40.4%). Group B, where the eyes acquired two traditional arch segments, showed an average Km decrease of 2.66D (5.1%) and corneal astigmatism reduction of 2.11D (34.8%). The mean keratometry (Km) reduction obtained was statistically significant (p≤0.05) when comparing both groups (A and B). The mean corneal astigmatism reduction was not statistically significant (p≤0.05) when comparing both groups (A and B). Conclusions: One long-arch segment has been demonstrated to have a greater capacity to reduce corneal curvature when compared to the use of two traditional-sized arch segments. No significant differences were found regarding the reduction of corneal astigmatism after comparing the results obtained in both groups.

Influência da espessura dos segmentos de anel corneano na correção do astigmatismo ceratométrico em pacientes com ceratocone / Influence of corneal ring segment thickness on correction of corneal astigmatism in patients with keratoconus

RESUMO Objetivo: Avaliar retrospectivamente a influência da espessura do anel intracorneano na redução do astigmatismo corneano em pacientes portadores de ceratocone. Métodos: De um banco de dados com 2.033 olhos submetidos à cirurgia de implante de anel corneano, foi selecionada uma amostra de 90 olhos com características semelhantes em relação à ceratometria e ao astigmatismo. Todos os olhos deste estudo receberam dois segmentos de comprimento de arco tradicional de aproximadamente 160°, com espessuras variadas: Grupo A recebeu dois segmentos de 150µm; Grupo B recebeu dois segmentos de 200µm, e Grupo C recebeu dois segmentos de 250µm. As variáveis analisadas foram ceratometria média e astigmatismo corneano pré e pós-operatório. Resultados: Nos olhos que receberam dois segmentos de anel de 150µm de espessura (Grupo A), houve redução média de 5,0D (10%) em relação à ceratometria média e redução média de 3,26D (57,69%) em relação ao astigmatismo corneano. Na amostra em que foram utilizados dois segmentos de 200µm (Grupo B), foi observada redução da ceratometria média de 7,0D (14,28%) e do astigmatismo corneano de 3,53D (63,6%). Já na amostra que recebeu dois segmentos de anel de 250µm de espessura (Grupo C), a redução média da ceratometria foi de 10D (20,4%) e de seu astigmatismo corneano de 2,09D (38,99%). Conclusão: Nos pacientes com ceratocone submetidos à cirurgia de anel corneano, o aumento da espessura dos segmentos implantados promove maior aplanamento da córnea, mas não o aumento em sua capacidade de reduzir o astigmatismo ceratométrico. Seria interessante a análise de uma amostra maior de pacientes, aliada a cálculos vetoriais de astigmatismo, para comprovar os achados deste estudo.

ABSTRACT Objective: To retrospectively evaluate the influence of intracorneal ring thickness on reduction of corneal astigmatism in patients with keratoconus. Methods: From a database of 2,033 eyes submitted to corneal ring implant surgery, a sample of 90 eyes with similar keratometry and astigmatism characteristics was selected. All eyes in this study received two segments of traditional arc length of approximately 160°, with varying thicknesses: Group A received two segments of 150 µm; Group B received two segments of 200 µm, and Group C received two segments of 250 µm. The variables analyzed were mean keratometry and corneal astigmatism before and after surgery. Results: In the eyes that received two 150-µm ring segments (Group A), there was a mean reduction of 5.0 D (10%) in relation to mean keratometry, and a mean reduction of 3.26 D (57.69%) in relation to corneal astigmatism. In the sample in which two 200-µm segments (Group B) were used, there was a mean reduction in keratometry of 7.0 D (14.28%) and in corneal astigmatism of 3.53 D (63.6%). In the sample receiving two 250-µm ring segments (Group C), the mean reduction in keratometry was 10 D (20.4%) and in corneal astigmatism was 2.09 D (38.99%). Conclusion: In keratoconus patients undergoing corneal ring surgery, increased thickness of the implanted segments promotes greater flattening of the cornea, but does not enhance their ability to reduce corneal astigmatism. It would be interesting to analyze a larger sample of patients, combined with vector calculations of astigmatism, to confirm the findings of this study.