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- Analysis of conjunctival vascular density in scleral contact lens wearers using optical coherence tomography angiographyPublication . Jesus, Jeniffer; Dias, Libânia; Almeida, Inês; Costa, Tatiana; Chibante-Pedro, JoãoTo investigate conjunctival vascular density (VD) using Anterior Segment Optical Coherence Tomography Angiography (OCTA) in Scleral Contact Lens (ScCL) wearers. In this cross-sectional study, the conjunctival blood VD was assessed using OCTA with an anterior segment lens adapter. The nasal surface of each eye (6 ×6 mm) was scanned to a depth of 800 μm with ScCL and fifteen minutes after removing the lens. Conjunctival VD was defined as the percentage of the scanned volume occupied by vessels in which blood flow was measured. Measures of limbal indentation were subjectively determined by two independent observers using Anterior Segment Optical Coherence Tomography (AS-OCT). Comparisons between VD measurements before and after ScCL removal and correlations between conjunctival VD, time of use, vault and indentation values were also investigated. A total of 23 patients (3 females, 20 males) with keratoconus, with a mean age (years±SD) of 38.74±10.38 were included in the study. VD was significantly higher without ScCL (71.75%±2.97) than VD measured with ScCL (69.81%±2.63), p=0.02. A moderately negative correlation was found between indentation and vault (r=-0.44, p<0.05) and a positive tendency regarding the time of wearing ScCL and indentation (r=0.11 and r=0.068, respectively). Using OCTA with an anterior segment lens adapter, the ocular surface blood VD was imaged and assessed with good repeatability and reliability. This study presents a new possible application of OCTA to investigate and monitor conjunctival vasculature in ScCL wearers. This results cautiously suggest that the repeated use of ScCL can cause vascular alterations in conjunctiva of the eyes of ScCL wearers, possibly due to a hidden hypoxia caused by prolonged limbal indentation.
- Optical coherence tomography angiography in herpetic leucomaPublication . Almeida, Inês; Dias, Libânia; Jesus, Jenifer; Fonseca, Inês; Matias, Maria João; Pedro, João CarlosHerpes simplex virus (HSV) keratitis remains a leading infectious cause of blindness worldwide. Although all forms of HSV keratitis are commonly recurrent, the risk is greatest in stromal keratitis, which is the most likely to result in corneal scarring, thinning, and neovascularization. Recent studies showed the ability of Optical Coherence Tomography Angiography (OCTA) to detect and study vascular abnormalities in the anterior segment, including abnormal corneal vessels. This study intends to investigate the potential of OCTA device to image and describe quantitatively the vascularization in eyes diagnosed with herpetic leucoma and to discuss and review the usefulness of this technique in this pathology. A Cross-sectional study was made, including 17 eyes of 15 patients with leucoma secondary to herpetic keratitis. All eyes underwent anterior segment Slit-Lamp photography (SLP), and OCTA with en-face, b-scans and c-scans imaging. The vessel density (VD) was analyzed in the inferior, nasal and temporal corneal margin in all patients, and in the central area, in eyes with central corneal neovascularization (CoNV). The measurements were calculated after binarization with ImageJ software, using OCTA scans with 6 × 6 mm in a depth of 800 μm. Patients included had a mean age 53.267 ± 21.542 (years ± SD). The mean total vessel area was 50.907% ± 3.435%. VD was higher in the nasal quadrant (51.156% ± 4.276%) but there were no significant differences between the three analyzed areas (p = 0.940). OCTA was able to identify abnormal vessels when SLP apparently showed no abnormal vessels; OCTA was able to distinguish between larger and smaller vessels even in central cornea; OCTA scans allowed the investigation of several corneal planes and the relation of them with clinical findings. OCTA can be useful in both qualitative and quantitative follow-up of patients and may become a non-invasive alternative to objectively monitor treatment response in eyes with corneal vascularization due to herpetic infection.
- Angiografia por tomografia de coerência ótica na queratoplastia penetrantePublication . Aguiar, Catarina Pestana; Jesus, Jeniffer; Dias, Libânia; Gonçalves, Susana; João, Matias Maria; Miranda, Vítor; Ambrósio, João; Chibante-Pedro, João; Almeida, InêsA queratoplastia penetrante (QP) é um dos procedimentos cirúrgicos mais realizados na transplantação corneana mundialmente. A falência do enxerto e o risco de rejeição aumentam progressivamente com o aumento do número de quadrantes com neovascularização corneana (NVC). A angiografia por tomografia de coerência ótica (OCTA) é um exame não invasivo que tem sido largamente utilizado na visualização de anomalias vasculares da retina e algunsestudos demonstraram a sua potencial utilização no segmento anterior do olho. O objetivo deste estudo foi investigar o potencial da tecnologia da OCTA na aquisição de imagens e descrição quantitativa da NVC em olhos submetidos a QP. Estudo transversal, com 20 olhos de 18 doentes submetidos a QP pelo menos 5 anos antes e sem história de rejeição do transplante. A todos os olhos foi realizada uma fotografia do segmento anterior na lâmpada de fenda (LF) e uma aquisição de imagens en face, b-scans e c-scans da OCTA. A densidade vascular (DV) foi analisada na margem corneana inferior, nasal e temporal em todos os doentes. A medição da DV foi obtida após criação de imagens binárias com o software ImageJ, usando imagens da OCTA com 6 × 6 mm numa profundidade de 800 μm. A idade média dos doentes foi de 59 anos e a maioria foi submetido a QP por leucoma corneano, seguido de queratocone. A DV total média foi de 50,16% e foi mais alta no quadrante temporal e mais baixa no quadrante inferior. No entanto, não se verificou uma diferença estatisticamente significativa entre as 3 áreas analisadas (p=0,801) ou entre cada área e as duas restantes e não se verificou uma correlação entre as áreas. A OCTA foi capaz de identificar vasos anormais quando as fotografias na LF não os identificavam; a OCTA foi capaz de distinguir entre vasos de grande e pequeno calibre; a OCTA permitiu a investigação em diferentes planos corneanos. A OCTA poderá tornar-se um novo método para a monitorização de doenças corneanas e permitir o seguimento qualitativo e quantitativo de pacientes submetidos a QP, com a deteção precoce de NVC.
- Analysis of choroidal macular thickness in early post-Covid-19 patientsPublication . Jesus, Jeniffer Domingues de; Soares, Raquel J.; Dias, Libânia; Ventura, Suzana M.; Pedro, João C.Corona Virus Disease 2019 (COVID-19) is considered a critical global health challenge. Several investigations have suggested vascular dysfunction caused by Severe Acute Respiratory Syndrome Coronavirus 2 (SARS-CoV-2) infection, but regarding ophthalmic involvement, only few data are available. Our aim was to evaluate the choroidal involvement in post-COVID-19 patients. 40 eyes from 40 patients with previous SARS-CoV-2 infection and 40 eyes from 40 age matched controls were included. Choroidal measurements were made using Enhanced Depth Imaging Optical Coherence Tomography (EDI-OCT) at 13 different locations: at central fovea and at intervals of 500μm to 1500μm away from the fovea in the temporal, nasal, superior and inferior regions. Post-COVID-19 patients showed a significant increase in choroidal thickness compared with the control group for all the regions analyzed (all p <0.01). In the Post-COVID-19 group, the choroid is thickest subfoveally and thinnest 1500μm nasal from fovea. In both groups, the superior and temporal macular choroid has been measured thicker than the inferior and nasal macular choroid, respectively. Our results cautiously suggest that post-COVID-19 patients showed an increase in choroidal thickness compared to control groups. This choroidal thickening may reflect the importance of vascular factors in the pathogenesis of SARS-CoV-2 infection. Keywords: Choroid; COVID-19; Hemodynamic Changes; Ocular Circulation; Retina; SARS-CoV-2