Role of Anterior Segment Optical Coherence Tomography in Staging and Evaluation of Treatment Response in Infectious Keratitis

PURPOSE

The aim of this study was to evaluate the role of anterior segment optical coherence tomography during follow-up of infectious keratitis and to assess response to treatment.

METHODS

This was a prospective, consecutive, observational clinical series of cases. Twenty-three eyes of 23 patients with clinically proven fungal keratitis were included in the study. The patients received medical treatment according to clinical diagnosis, and follow-up was performed weekly. Slit-lamp examination and photography, and anterior segment optical coherence tomography were performed at initial and follow-up visits until corneal healing occurred. The main outcome measures included infiltrate depth, width, and density; central corneal thickness; minimal corneal thickness; corneal thickness at the site of the lesion; and stromal thickness at the center of the lesion.

RESULTS

Twenty-three eyes of 23 patients (17 men and 6 women), mean age 42.5 ± 19 (8-66) years, were clinically diagnosed with fungal keratitis. Localization was central in 14 cases and paracentral/peripheral in 9 cases. Healing time was 6 to 12 weeks. Minimal corneal thickness, corneal thickness at the site of lesion, and stromal thickness at the center of lesion, and also infiltrate width and depth changed significantly from the first visit to the healing stage at the last follow-up (0.009, 0.001, 0.007, 0.001, and <0.001, respectively).

CONCLUSIONS

In cases of fungal keratitis, anterior segment optical coherence tomography can provide the clinician with a quantitative assessment of a number of corneal parameters that can be used to determine effectiveness of therapy and confirm complete healing of the lesions that cannot be achieved by clinical evaluation.

CLINICAL TRIAL REGISTRATION

The study was registered in Clinical Trials.gov with NCT04969640.

Evaluation of the corneal thickness and endothelial changes following uncomplicated phacoemulsification in diabetic and non-diabetic patients with pseudo-exfoliation syndrome by specular microscopy

PURPOSE

To evaluate corneal endothelial cell changes following uncomplicated phacoemulsification in diabetic patients with PEX, compared with diabetic patients and non-diabetic patients with PEX.

METHODS

This prospective, comparative, non-randomized cohort study included 61 eyes of 61 patients who were diagnosed as having senile cataract. Patients were divided into three groups: Group (1) included 19 eyes of patients with DM and PEX, group (2) included 22 eyes of diabetic patients, and group (3) included 20 eyes of patients with PEX. All included patients had uncomplicated phacoemulsification with IOL implantation. Patients were examined by non-contact specular microscopy (NIDEK, CEM-530, Japan), preoperatively and postoperatively at regular follow-up periods (one, three, and six months postoperatively) with analysis of the endothelial cell density, percentage of hexagonal cells, CV, and CCT.

RESULTS

By the end of follow-up period, there was a statistically significant reduction in ECD and HEX with a significant increase in CV and CCT in group one (DM-PEX). In group two (DM), a statistically significant decrease in ECD and HEX with a significant increase in CCT was reported, while in group three (PEX), the only significant difference was found in the form of ECD reduction.

CONCLUSION

Patients with DM and PEX had significant changes regarding ECD, CV, HEX, and CCT which were more pronounced than in patients with DM only or PEX only. More attention should be paid while operating on diabetic patients with PEX to save corneal endothelium and decrease postoperative complications.

STUDY REGISTRATION NUMBER

The study was retrospectively registered (16 July 2021) on ClinicalTrials.gov (NCT04965168).

Assessment of macular microvascular changes in children following treatment of anisometropic myopic amblyopia using optical coherence tomography angiography

PURPOSE

To evaluate macular microvascular changes in the form of foveal avascular zone (FAZ) area and vessel density in the superficial, deep capillary plexuses, and choriocapillaris using optical coherence tomography angiography (OCTA) in children with anisometropic myopic amblyopia before and after treatment.

METHODS

This prospective observational study included 32 patients younger than 12 years old with anisomyopic amblyopia. OCTA was done before patients' treatment with optical correction with or without patching and was repeated after successful amblyopia treatment. Outcomes included superficial, deep, and choriocapillaris vessel density (VD) and superficial and deep FAZ areas.

RESULTS

The study included 13 males (40.6%) and 19 females (59.4%), and the mean age was 9.52 ± 1.33 years. Fifty-three percent (53%) of patients needed only optical correction, and the remaining 47% needed additional patching therapy. After successful treatment, there was a significant improvement in amblyopic eyes in best-corrected visual acuity (p < 0.001), with higher VD values in superficial capillary plexuses (p < 0.001), deep capillary plexuses (p < 0.001), and foveal choriocapillaris (p = 0.030). In the glasses with patching subgroup, the difference between pre-treatment and post-treatment parameters revealed a significant improvement in vessel density in superficial retinal plexuses (foveal and parafoveal; p values 0.023 and < 0.001, respectively) and deep retinal plexuses (whole image, foveal, and parafoveal; p values 0.003, < 0.001, and 0.002, respectively). While amblyopic eyes treated with glasses alone had a significantly greater difference in choriocapillaris foveal VD (p value = 0.022).

CONCLUSION

After effective amblyopia treatment, amblyopic eyes exhibited improved best-corrected visual acuity and better macular perfusion along the superficial, deep vascular density, and choriocapillaris foveal VD.

CLINICAL TRIAL REGISTRATION

CinicalTrials.gov Identifier: NCT05223153.

Clinical Outcomes of Toric Implantable Collamer Lens (T-ICL) and Toric Implantable Phakic Contact Lens (IPCL) for High Myopia with Astigmatism: A Comparative Study

Background:

Our study aimed to compare the clinical, visual outcomes, and efficacy of toric Implantable Collamer Lens (T-ICL) and toric implantable phakic contact lens (IPCL) in patients with high myopia and astigmatism over a follow-up period of 6 months.

Methods:

A prospective interventional randomized comparative study included 60 myopic eyes divided into 2 groups, group A including 30 eyes that were implanted with T-ICL, and group B, including 30 eyes that were implanted with toric IPCL. The refractive results, visual acuity, central corneal endothelial cell count, and intraocular pressure (IOP) were evaluated at baseline and at 1 and 6 months post-surgery. Any complications either during or after surgery were assessed.

Results:

In both study groups, the mean central corneal endothelial cell count was significantly decreased after 1 month and improved to reach near pre-operative values after 6 months postoperatively, indicating good lens biocompatibility. A statistically significant increase in IOP was found in both groups during the early follow-up, and a significant decrease after 6 months postoperatively (p=0.036) was reported in group A. A significant reduction in both spherical and cylindrical refractive errors with good predictability was reported in both groups compared with pre-operative values. Regarding the predictability, In T-ICL group (A), the median spherical and cylindrical errors were significantly improved from (-10 D & -4.5 D) pre-operatively to (-0.3 D & - 0.3 D) at the end of 6 months follow up period. Similarly, in the toric IPCL group (B), the median spherical and cylindrical errors were significantly improved from (-11 D & -4.5 D) pre-operatively to (-0.3 D & - 0.3 D) by the end of follow up period. A statistically significant improvement of UCDVA at 6 months postoperatively was found in both groups, as median preoperative LogMAR UCDVA was 1.1 and 1.3 in groups A and B respectively, which was improved to 0.3 in both groups at the end of follow-up period. There were no reported intra- or postoperative complications such as cataract, keratitis, or lens decentration.

Conclusion:

Toric IPCL is a suitable alternative to T-ICL for the management of high myopia with astigmatism, especially in developing countries, as it is cheaper and easier to implant than T-ICL. However, data over longer follow-up periods are needed to confirm its safety and stability.

Evaluation of implanted perforated lacrimal punctal plugs using anterior segment optical coherence tomography

Purpose

Evaluation of the patency and position of perforated lacrimal punctal plugs implanted for treating punctal stenosis together with quantitative assessment of the precorneal tear film using anterior segment optical coherence tomography (AS-OCT).

Methods

In a prospective study, the lower punctum of 54 eyes of 29 patients implanted with perforated punctal plugs were examined using AS-OCT during the early postoperative period. Preoperative tear meniscus height (TMH) and tear meniscus area (TMA) were evaluated. Postoperatively, the patency of the plug, its position, TMH and TMA were evaluated, and the results were correlated with postoperative epiphora. Munk scale was used for epiphora grading.

Results

Using AS-OCT, 48 (88.9%) plugs were found in proper position while 6 (11.1%) were rotated. The lumen of the plugs was completely patent in 47 (87%) plugs, partially obstructed in 2 (3.7%) plugs and completely occluded in 5 (9.2%) plugs. There was a statistically significant postoperative decrease of TMH and TMA (P < 0.001) and postoperative epiphora Munk score (P < 0.001).

Conclusion

AS-OCT is a valuable, reliable, and noninvasive investigative tool that can detect the proper positioning, patency, and contents of the implanted perforated lacrimal punctal plugs in addition to measurement of TMH and TMA.

Trial registration ClinicalTrials.gov ID: NCT04624022, https://clinicaltrials.gov/ct2/show/NCT04624022

Supplementary Information

The online version contains supplementary material available at 10.1186/s40662-021-00259-x.

Macular microvascular changes in children with transfusion-dependent beta-thalassemia

BACKGROUND

To investigate the effect of iron overload on macular perfusion among transfusion-dependent thalassemia (TDT) patients using optical coherence tomography angiography (OCTA) METHODS: The study is a prospective observational case-control study. It included 27 eyes from 27 children with transfusion-dependent β-thalassemia and 25 eyes from 25 age-matched controls. All participants were evaluated clinically and with OCTA Avanti RTVue-XR system (Optovue) to assess macular microvascular changes, by measuring vessels density (VDs) and foveal avascular zone (FAZ) area, at both superficial and deep retinal plexuses and at choriocapillaris level.

RESULTS

Foveal and parafoveal zones were significantly thinner among thalassemia patients, with significantly larger FAZ area at the level of both superficial and deep retinal plexuses when compared with control group. The thalassemia group showed significant lower values compared with the controls regarding whole-image, foveal, and parafoveal deep VD. There were significant negative correlations between serum ferritin and deep (whole image and parafoveal) VD (r =  - 0.429, P = 0.026, and r =  - 0.452, P = 0.018, respectively). Choriocapillaris VDs (whole image and foveal) showed significant negative correlations with serum ferritin levels (r =  - 0.390, P = 0.044 and r =  - 0.401, P = 0.038, respectively) CONCLUSIONS: Macular microvascular changes were detected by OCTA examination in patients with TDT, mostly due to iron overload effect, as we selected patients on iron-chelating agent with the least harmful effect on the retina. The most affected layer is the DCP. Changes at the deep layer could be used as a sensitive biomarker for early macular perfusion changes in those patients.

TRIAL REGISTRATION

Study registration number is UMIN000042657, date of registration: 2020/12/04 (retrospectively registered).

Quantification of Macular Microvascular Changes in Retinitis Pigmentosa Using Optical Coherence Tomography Angiography

Purpose

To investigate macular structural and microvascular changes in retinitis pigmentosa (RP) eyes compared to age-matched controls using spectral domain optical coherence tomography (SD-OCT) and OCT angiography (OCTA).

Methods

This was a cross-sectional study. The foveal and parafoveal thickness and extent of ellipsoid zone (EZ) disruption were measured on OCT. The foveal avascular zone (FAZ) area and retinal vessel density (VD) were automatically calculated for superficial (SCP) and deep capillary plexuses (DCP) and choriocapillaris using OCTA-integrated software. VD was assessed for the whole 6 × 6 mm image, foveal and parafoveal regions. Quantitative measures were compared between healthy and diseased eyes.

Results

The study included 30 eyes of 30 RP patients and 24 eyes of 24 controls. Mean age was 26.9±6.4 years for RP patients and 27.4±4.9 years for controls (p=0.76). Mean LogMAR visual acuity (VA) was 0.9±0.5 for RP patients and 0.05±0.05 for controls (p <0.001). Foveal and parafoveal thicknesses were significantly lower in RP cases as compared to the control group. EZ disruption was observed in RP cases only (869±211 µm). Mean FAZ area was significantly larger in RP eyes in both SCP and DCP. VD was significantly reduced in RP eyes at the level of SCP, DCP and choriocapillaris. VA, deep parafoveal VD, foveal, parafoveal and whole image choriocapillaris VD were negatively correlated with the extent of EZ disruption.

Conclusion

We report OCTA findings in a relatively young cohort of RP patients. We demonstrated a reduction of retinal microvascular density in all studied layers on OCTA. We believe studying retinal vasculature in these patients is important, as a healthy blood supply is a prerequisite for the success of new cell-based therapies under trial for RP.

Evaluation of acquired punctal stenosis using anterior segment optical coherence tomography

BACKGROUND/OBJECTIVES

The aim of this article was to study the lower punctum parameters in patients with acquired punctal stenosis using spectral-domain anterior segment optical coherence tomography.

SUBJECTS/METHODS

This was a prospective nonrandomized study that included two groups. Group 1 was composed of 32 puncta from 32 subjects (11 males and 21 females, aged 40-62 years) with epiphora and clinically diagnosed punctal stenosis. Group 2 (control group) included 30 puncta from 30 normal subjects (10 males and 20 females, aged 43-63 years). Anterior segment optical coherence tomography was employed to evaluate lower punctum parameters in all subjects; the inner and outer punctal diameters as well as punctal depth were measured.

RESULTS

External punctal diameter (mean: 466.1 ± 120.3 μm), internal punctal diameter (mean: 173.4 ± 55.6 μm) and punctal depth (mean: 188.4 ± 67 μm) values in Group 1 were statistically significantly lower than those in Group 2 (mean: 745.7 ± 156.9 μm, mean: 384 ± 119.1 μm, and mean: 284.9 ± 57.7 μm, respectively).

CONCLUSION

Anterior segment optical coherence tomography could possibly be used as a noncontact and noninvasive diagnostic modality for evaluating and measuring the lower punctum in patients with punctal stenosis. Further research is required to develop a normative database and grading system for stenosed puncta and to correlate the degree of stenosis with the severity of epiphora.

Assessment of Posterior Segment Using Spectral Domain OCT in Highly Myopic Eyes

Purpose:

Spectral Domain Optical Coherence Tomography (SD-OCT) was used to evaluate retinal and vitreo-retinal changes that occur in highly myopic patients.

Methods:

This prospective study included 472 eyes of 472 patients suffering from high myopia (> -6.00 D), between May 2012 and December 2015. All patients were examined, using Cirrus HD OCT (Zeiss Cirrus TM HD-OCT model 4000), to detect any retinal or vitreo-retinal interface abnormalities.

All obtained data was analyzed using Statistical Package for the Social Sciences software version 17 (SPSS Inc, Chicago, IL, USA) and the paired two-sided t-test. Bivariate correlations were performed between different parameters using the Spearman correlation coefficient (r).

Results:

Mean spherical equivalent (MSE) was -13.11± 4.35D. Mean axial length (AL) was 28.5±1.62 mm. Posterior vitreous detachment (PVD) was the most frequent OCT finding; representing 33.4% of the cases, 13.7% of them were associated with macular traction. A statistically significant positive correlation was found between AL and MTM, full thickness macular hole, PVD with traction, and dome shaped macula (r = 0.49 and P = 0.001, r = 0.422 and P = 0.0001, r = 0.25 and P = 0.03, r=0.475, P=0.001 respectively)

Conclusion:

OCT is a valuable tool in detecting retinal and vitreo-retinal interface abnormalities in highly myopic eyes, and it can be used for follow up of those patients to avoid advanced retinal damage.

Evaluation of Optic Nerve Head Parameters and Retinal Nerve Fiber Layer Thickness in Axial Myopia Using SD OCT

Introduction

The purpose of this research was to study the effect of increased axial myopia, in non-glaucomatous eyes, and its correlation with ONH parameters, and RNFL thickness, using Cirrus HD 4000 SD-OCT.

Methods

The myopia group included 86 eyes of 86 patients, while the control group involved 92 eyes of 92 patients, attending the Ophthalmology Outpatient Clinic in Minia University Hospital, between November 2013 and March 2015. ONH parameters and peripapillary RNFL thickness measurement were evaluated by using SD-OCT, selecting the standard optic disc cube 200 × 200.

Results

The mean age of the myopia group was (36.55 ± 9.44), the mean spherical equivalent was (−12.70 ± 3.87 D), and the mean axial length was (27.88 ± 1.92 mm). The control group had mean age of (34.82 ± 8.87), mean spherical equivalent of −0.65 ± 0.41 D, and mean AL of (22.16 ± 0.82). A significant difference was reported between the two groups, regarding disc area (p = 0.01), rim area (p = 0.001), vertical C/D (p = 0.01), average C/D ratio (p = 0.001), average and temporal RNFL thickness (p = 0.0001, p = 0.001, respectively).

Conclusion

A significant difference was found between highly myopic non-glaucomatous eyes and the control group, regarding ONH parameters and RNFL thickness as measured by SD-OCT. As OCT magnification adjusted ONH parameters were larger, global and the temporal RNEL were thicker in the myopia group, those magnification adjusted parameters helped in an accurate evaluation of ONH and RNFL in highly myopic eyes, in order to avoid misdiagnosis of glaucoma in such eyes.