Background: Previous studies have proposed an automated customized program named MATLAB used in the foveal avascular zone (FAZ) measurements in Triton optical coherence tomography angiography (OCTA) images. But it is not open-source and not easy to obtain, which will largely restrict its application in clinical practice and medical research. In this study, we aimed to investigate the feasibility of the Smooth Level Sets macro (SLSM), a free and open-source program, and compared with the manual measurements and MATLAB in the FAZ quantification in Triton OCTA.
Methods: Thirty-five eyes of 35 healthy subjects were scanned four times continuously using Triton OCTA. Manual and automated methods including the SLSM and MATLAB were used in the FAZ metrics (area, perimeter, and circularity) of the superficial capillary plexus. The accuracy, repeatability of all methods, and agreement between automated and manual methods were analyzed.
Results: The SLSM presented higher accuracy with a higher average Dice coefficient (0.9506) than MATLAB (0.9483), which was just second to the manual method (0.9568). Both the SLSM [intraclass correlation coefficient (ICC) =0.987; coefficient of variation (CoV) =3.935%] and MATLAB (ICC =0.983; CoV =4.165%) showed excellent repeatability for the FAZ area. They also had excellent agreement with manual measurement (SLSM, ICC =0.973; MATLAB, ICC =0.968).
Conclusion: The SLSM exhibits better accuracy than MATLAB in the automated FAZ measurement in Triton OCTA, the results of which were comparable to those obtained by manual measurement. This free and open-source program may be an accessible and feasible option for automated FAZ segmentation on Triton OCTA images.
ABSTRACT Aim We report two cases of endothelial corneal allograft rejection following immunisation with SARSCoV-2 messenger RNA (mRNA) vaccine BNT162b2 and describe the implications for management of transplant recipients postvaccination for COVID-19. Methods A 66-year-old woman with Fuchs endothelial corneal dystrophy (FECD) and a unilateral Descemet’s membrane endothelial keratoplasty (DMEK) transplant received COVID-19 mRNA vaccine BNT162b2 14 days post-transplant. Seven days later, she presented with symptoms and signs of endothelial graft rejection. An 83-year-old woman with bilateral DMEK transplants for FECD 3 and 6 years earlier developed simultaneous acute endothelial rejection in both eyes, 3weeks post second dose of COVID-19 mRNA vaccine BNT162b2. Rejection in both cases was treated successfully with topical corticosteroids. Conclusions We believe this is the first report of temporal association between corneal transplant rejection following immunisation against COVID-19 and the first report of DMEK rejection following any immunisation. We hypothesise that the allogeneic response may have been initiated by the host antibody response following vaccination. Clinicians and patients should be aware of the potential of corneal graft rejection associated with vaccine administration and may wish to consider vaccination in advance of planned non-urgent keratoplasties. Patients should be counselled on the symptoms and signs that require urgent review to allow early treatment of any confirmed rejection episode.
Low vision is a serious visual impairment. Due to low vision status, patients often face varying degrees of difficulties in their daily lives, studies, and work. Low vision rehabilitation refers to the use of visual rehabilitation, rehabilitation training, and other methods to help patients maximize their ability to maintain independence and improve their quality of life. This study provides a certain reference basis for clinical low vision rehabilitation work by summarizing the epidemiological status and rehabilitation status of low vision both domestically and internationally.
Objective: To evaluate the effectiveness of music therapy on the anxiety level and physiological response of patients undergoing ophthalmic surgery.
Methods: Relevant randomized controlled trials that compared the combined effect of music therapy for patients undergoing ophthalmic surgery were included. Four English databases and three Chinese databases were searched from inception to Jan. 2022. Two reviewers independently performed data extraction and risk of bias assessments. The Cochrane Collaboration tool was used to assess the risk of bias. Meta-analysis was performed using Review Manager 5.3. The outcomes were overall anxiety, blood pressure, heart rate and pain.
Results: Atotal of 11 trials with 1,469 participants were included in the meta-analysis. Compared to standard care, music therapy had a good effect on reducing the anxiety levels of patients undergoing ophthalmic surgery (p<0.05). The results also suggested that music therapy produced a signifcant improvement in blood pressure (p<0.05) and heart rate (p<0.05). The visual analogue scale (VAS) showed that music therapy signifcantly reduced pain compared to standard care (p<0.05).
Conclusions: This meta-analysis provided evidence that music therapy has an obvious efect on relieving anxiety levels, while it is also more effective in alleviating pain and improving physiological responses than standard care alone. Our fndings may provide accurate evidence-based guidance for the clinical implementation of music therapy. In the future, more high-quality studies are required for verifying these results.
Background: A variety of experimental animal models are used in basic ophthalmological research to elucidate physiological mechanisms of vision and disease pathogenesis. The choice of animal model is based on the measurability of specific parameters or structures, the applicability of clinical measurement technologies, and the similarity to human eye function. Studies of eye pathology usually compare optical parameters between a healthy and altered state, so accurate baseline assessments are critical, but few reports have comprehensively examined the normal anatomical structures and physiological functions in these models.
Methods: Three cynomolgus monkeys, six New Zealand rabbits, ten Sprague Dawley (SD) rats, and BALB/c mice were examined by fundus photography (FP), fundus fluorescein angiography (FFA), and optical coherence tomography (OCT).
Results: Most retinal structures of cynomolgus monkey were anatomically similar to the corresponding human structures as revealed by FP, FFA, and OCT. New Zealand rabbits have large eyeballs, but they have large optic disc and myelinated retinal nerve fibers in their retinas, and the growth pattern of retinal vessels were also different to the human retinas. Unlike monkeys and rabbits, the retinal vessels of SD rats and BALB/c mice were widely distributed and clear. The OCT performance of them were similar with human beings except the macular.
Conclusions: Monkey is a good model to study changes in retinal structure associated with fundus disease, rabbits are not suitable for studies on retinal vessel diseases and optic nerve diseases, and rats and mice are good models for retinal vascular diseases. These measures will help guide the choice of model and measurement technology and reduce the number of experimental animals required.
Background: Patients with dacryocystitis should be treated for their infection by endoscopic dacryocystorhinostomy (EN-DCR) before any intraocular surgery. However, there is no unified standard for the specific time interval between the two surgeries. This study aimed to determine the appropriate interval for intraocular surgery in patients with previous EN-DCR for chronic dacryocystitis.
Methods: The medical files of all patients who underwent intraocular surgery after EN-DCR surgery in our hospital from 2016 to 2019 were reviewed. The EN-DCR data of patients undergoing intraocular surgery at different time intervals and the incidence of endophthalmitis after intraocular surgery were compared.
Results: A total of 116 patients (92 females and 24 males, mean age 64.06±7.78 years) underwent EN-DCR and intraocular surgery met the inclusion criteria. The interval between EN-DCR and intraocular surgery varied from 5–475 days. The number of patients undergoing cataract surgery after EN-DCR is the largest (75, 64.7%). All patients (100%) who had previously undergone EN-DCR did not develop endophthalmitis infection after intraocular surgery at a follow-up of 12 months.
Conclusions: For patients with dacryocystitis who have undergone EN-DCR surgery, there is no time limit when choosing the timing of intraocular surgery. For patients requiring intraocular surgery, operation can be arranged as soon as possible to solve their problems as long as the patients had patency on lacrimal passage irrigation and no secretions.
Retrobulbar block refers to the injection of local anesthetics into the muscle cone behind the eyeball, blocking the ciliary, oculomotor, and ciliary ganglion nerves, to provide pain relief, restrict eye movement, and reduce intraocular pressure. Modern retrobulbar block is the "gold standard" for eyeball immobilization and anesthesia in intraocular surgeries, and it is the one of the most commonly used methods for ocular regional block. Although the complications related to this method are rare, the complications will threaten the vision and even life. Th is expert consensus introduces the application scope of retrobulbar block, and systematically describes functional neuroanatomy of eye sensation and movements, safety and procedures of retrobulbar block, local anesthetics, contraindications and complications of the block, which can provide the reference for clinical application of this method.
Background: The “flipped classroom” is a learner-centered approach that centers on delivering videos,podcasts or slide-based material to learners prior to a lecture or class session. The class session is then dedicated to discussion, analysis, and problem-solving activities. The aim of this study was to investigate whether the flipped classroom could be adapted to medical (ophthalmology) students learning about ocular trauma and to assess the impact of the flipped classroom on those students’ performance and attitudes.
Methods: Questionnaires (using a 4-point scale) were distributed to 93 fifth-year medical students at Sun Yat-sen University, and the data showed that the majority of students preferred the flipped classroom approach to the traditional lecture method.
Results: The results of pre- and post-test scores were 14.35±3.404 and 20.37±4.356, which showed a significant improvement in students’ performance after the flipped classroom was introduced (P<0.05).
Conclusions: Student response to the flipped classroom strategy was largely positive, indicating that the strategy received a high level of approval in an ophthalmology clerkship course taken by medical students in China.
Backgrounds: To assess changes in anterior segment biometry during accommodation using a swept source anterior segment optical coherence tomography (SS-OCT).
Methods: One hundred-forty participants were consecutively recruited in the current study. Each participant underwent SS-OCT scanning at 0 and -3 diopter (D) accommodative stress after refractive compensation, and ocular parameters including anterior chamber depth (ACD), anterior and posterior lens curvature, lens thickness (LT) and lens diameter were recorded. Anterior segment length (ASL) was defined as ACD plus LT. Lens central point (LCP) was defined as ACD plus half of the LT. The accommodative response was calculated as changes in total optical power during accommodation.
Results: Compared to non-accommodative status, ACD (2.952±0.402 vs. 2.904±0.382 mm, P<0.001), anterior (10.771±1.801 vs. 10.086±1.571 mm, P<0.001) and posterior lens curvature (5.894±0.435 vs. 5.767±0.420 mm, P<0.001), lens diameter (9.829±0.338 vs. 9.695±0.358 mm, P<0.001) and LCP (4.925±0.274 vs. 4.900±0.259 mm, P=0.010) tended to decreased and LT thickened (9.829±0.338 vs. 9.695±0.358 mm, P<0.001), while ASL (6.903±0.279 vs. 6.898±0.268 mm, P=0.568) did not change significantly during accommodation. Younger age (β=0.029, 95% CI: 0.020 to 0.038, P<0.001) and larger anterior lens curvature (β= -0.071, 95% CI: -0.138 to -0.003, P=0.040) were associated with accommodation induced greater steeping amplitude of anterior lens curvature. The optical eye power at 0 and -3 D accommodative stress was 62.486±2.284 and 63.274±2.290 D, respectively (P<0.001). Age was an independent factor of accommodative response (β= -0.027, 95% CI: -0.038 to -0.016, P<0.001).
Conclusions: During -3 D accommodative stress, the anterior and posterior lens curvature steepened, followed by thickened LT, fronted LCP and shallowed ACD. The accommodative response of -3 D stimulus is age-dependent.
