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Glaucoma
Published in Mary E. Shaw, Agnes Lee, Ophthalmic Nursing, 2018
Perimetry, posterior-segment examination and applanation tonometry are carried out to diagnose and monitor the disease. Corneal pachymetry is also performed to determine the thickness of the cornea.
Anterior segment OCT
Published in Pablo Artal, Handbook of Visual Optics, 2017
Corneal topography can be revealed by mapping the corneal thickness (pachymetry), surface elevation, or curvature/power mapping (keratometry) and plays an important role in the assessment of keratorefractive surgical procedures, corneal transplantation, or screening the corneal degenerations and dystrophies (e.g., keratoconus). There are several techniques enabling topographic description of the eye (Mejia-Barbosa and Malacara-Hernandez, 2001, Pinero, 2015). Access to volumetric data sets enables mapping the corneal thickness (corneal pachymetry). Several studies have been performed to show reproducibility of OCT pachymetry and agreement with standard instruments (Wirbelauer et al., 2002, Li et al., 2006, 2008, 2010, Pinero et al., 2008). The comparison of corneal pachymetry for normal subject and patient with keratoconus is presented in Figure 4.18 (Karnowski et al., 2011). The maps were calculated from corresponding 3-D data sets after segmentation of corneal interfaces and correction for light refraction.
Unilateral posterior polymorphous corneal dystrophy due to a novel ZEB1 gene mutation in a Korean girl
Published in Ophthalmic Genetics, 2022
Chae Yeon Lee, Ja-Hyun Jang, Gyule Han, Tae-Young Chung, Dong Hui Lim
A six-year-old healthy girl visited our clinic with decreased vision in the left eye. She had been diagnosed with amblyopia in the left eye one year ago and had started occlusion therapy. The best-corrected visual acuity (BCVA) of her left eye was 20/40 and cycloplegic refraction showed emmetropia. She and/or her guardian reported no systemic or ophthalmic medical history and denied trauma, congenital, or family history. During a slit-lamp examination, a “rail road track”-like lesion on the corneal endothelium was found in the left eye, while no abnormalities in the right eye were observed (Figure 1). Meanwhile, the rest of the anterior or posterior segment (fundus examination) was normal and the intraocular pressure was within normal range. Noncontact specular microscopy (SP-8800; KONAN Medical Inc., Hyogo, Japan) revealed an endothelial cell density of 1,938 cells/mm2 in the left eye but 3,571 cells/mm2 in the right eye (Figure 2). The central corneal thickness by ultrasound contact corneal pachymetry (Pachymeter SP-3000; Tomey, Japan) was measured as 651 μm in the left eye and 596 μm in the right eye. On Pentacam Scheimpflug imaging (Oculus Inc., Wetzlar, Germany) examination, inferior steepening was suspected in the left eye, while the right eye was normal (Figure 3). No abnormal findings were observed on slit-lamp examination of her parents.
Corneal Graft Rejection after Yellow Fever Vaccine: A Case Report
Published in Ocular Immunology and Inflammation, 2022
Roberto Vignapiano, Lidia Vicchio, Eleonora Favuzza, Michela Cennamo, Rita Mencucci
A diagnosis of corneal graft rejection was made in the left eye and the patient received topical dexamethasone sodium phosphate 0.15% 6 times a day, cyclopentolate 1% twice a day, and pulsed intravenous methylprednisolone 1000 mg in 500 ml of NaCl solution over 60 minutes for 3 days. The patient was admitted to our ophthalmological department to have intravenous methylprednisolone in day surgery. He was monitored and routine hematological tests were performed; he did not develop any signs or symptoms of systemic alterations. Three days later the left eye began to clear. BCVA was 10/10, the conjunctival hyperemia and graft edema reduced considerably and the KPs reduced and became brownish (Figure 2(a)). Fundoscopy was unremarkable and IOP was 16 mmHg. Corneal pachymetry showed a CCT of 594 µm while AS-OCT revealed a partial resolution of the previous findings (Figure 2(b,c)). Specular microscopy revealed an endothelial cell density of 1247 ± 56 cell/mm2. An oral regimen of dexamethasone was introduced. The patient was closely followed up for 3 months. Oral steroids were gradually discontinued over a month, topical steroids were tapered over the following weeks. No systemic and local adverse events or signs of graft rejection occurred in the follow-up period.
Longitudinal Changes in Corneal Epithelial Thickness and Reflectivity following Simple Limbal Epithelial Transplantation: An Optical Coherence Tomography-Based Study
Published in Current Eye Research, 2022
Anahita Kate, Tanvi Mudgil, Sayan Basu
ASOCT is a rapid, non-invasive tool that is also not very operator dependent. It has been used for the measurement of corneal reflectivity to assess the degree of corneal scarring. Wirbelauer et al. correlated the OCT findings with histopathology and found the device to be a good in vivo surrogate for objective morphometric assessment of corneal changes.16 Corneal reflectivity measured from an AS-OCT has also been used to assess tear film hyperosmolarity in dry eye disease, corneal scarring in various disorders and to quantify changes in the cornea in LSCD.14,17,18 Several other devices are also capable of recording corneal pachymetry and of these a corneal tomography probably provides the most composite representation of thickness in both the central and peripheral corneas. The Pentacam is one such device that captures a three-dimensional image of the cornea from nearly 25,000–138,000 separate points using a rotating Scheimpflug camera.19 Although a few studies have reported a good correlation between ASOCT and Pentacam-derived values, the pachymetry values from ASOCT are more accurate especially in eyes with corneal edema and scarring.20–23 Thus, this renders the ASOCT to be the modality of choice for measuring and monitoring changes in corneal thickness.