Intraocular endoscopy: A review

Learning Curve in Posterior Segment Ophthalmic Diagnostic Endoscopy: Implications for Budding Enthusiasts and Fellows-In-Training

PURPOSE

To elucidate the learning curve for posterior segment diagnostic endoscopy (DE) based on the results of a self-trained (ST) and a supervised (SUP) vitreoretinal surgeon.

METHODS

Retrospective review of medical records of DE performed between 2017 and 2023 by one ST and one SUP vitreoretinal surgeon at a tertiary eye care institute. Data were collected and the serial number of cases was plotted against the time taken for the procedure. A comparative regression plot was created for both the surgeons to know the slope of the learning curve. The start time was noted as that of attachment of the endoscope and the stop time was noted as the end of diagnostic evaluation. Procedures were divided into blocks of 10 cases each and the time taken for the procedures was calculated.

RESULTS

Total of 106 eyes (58 by ST surgeon and 48 by SUP surgeon) were included. For ST surgeon, the time taken for the surgery correlated inversely (reduced sequentially) with the serial number of the case till the 20th case (correlation coefficient = -0.5, p = .01), for SUP surgeon, the time taken for the surgery correlated inversely with the serial number of the case till the 10th case (correlation coefficient = -0.9, p = <0.0001) and then stabilized. Neither of the groups had any adverse events.

CONCLUSION

About 20 cases for a self-trained and about 10 cases for a supervised vitreoretinal surgeon are required to get stable with DE. These observations have implications in creating a training module for DE with appropriate number of training cases.

Consensus and controversies in the science of endophthalmitis management: Basic research and clinical perspectives

Infectious endophthalmitis is a severe intraocular infection caused by bacteria, or less commonly by fungi. It can occur after penetrating eye procedures, trauma, or the spread of infection from contiguous structures or via emboli from distant organs. Because of the time-critical nature of the treatment, endophthalmitis is treated with the clinical diagnosis and modified by the microbiological report of the intraocular contents. The current strategy for managing endophthalmitis relies on pre-clinical literature, case series, and one large multi-center randomized clinical trial on post-cataract surgery endophthalmitis. Culture-susceptibility of the microorganisms from undiluted vitreous guides the definitive treatment in non-responsive cases. Strategies to reduce the incidence of endophthalmitis after penetrating eye procedures have been developed concurrently with refined means of treatment. Despite these advances, outcomes remain poor for many patients. Although consensus articles have been published on managing endophthalmitis, treatment patterns vary, and controversies remain. These include (1) the use of newer methods for early and precise microbiological diagnosis; (2) the choice of intravitreal antibiotics; (3) the need for systemic therapy; (4) early and complete vitrectomy. Here, we review the current consensus and address controversies in diagnosing and managing endophthalmitis. This review is intended to familiarize physicians and ophthalmologists with different aspects of endophthalmitis management to make informed decisions.

Endoscopic cyclophotocoagulation for glaucoma compared to alternative procedures -A Systematic review

INTRODUCTION

Despite many recent developments, preference in the choice of surgical treatment of uncontrolled intraocular pressure (IOP) remains a challenge.

OBJECTIVE

This study compares the clinical efficacy and safety of endoscopic cyclophotocoagulation (ECP) to alternative surgical procedures, for all types of glaucoma.

METHODOLOGY

The methodology adheres to the preferred reporting items for systematic reviews and meta-analyses guidelines for systematic review reporting. Studies reporting ECP and alternative surgeries in treating refractory glaucoma, neovascular glaucoma, aphakic glaucoma, filtering surgical failure-induced glaucoma, congenital or juvenile glaucoma, and secondary glaucoma such as uveitis glaucoma, traumatic glaucoma, secondary glaucoma postcorneal transplantation, etc. were included. The efficacy was evaluated from the number of IOP-lowering drugs, and mean change in pre- and post-IOP were the outcomes assessed in ECP and non-ECP groups in this review. Evaluations of the postoperative complications revealed the safety assessment of the procedure.

RESULTS

In total, 11 relevant studies were selected in this study with a total of 5418 eyes, including 763 eyes in the ECP group and 4655 in the non-ECP group. This review observed that both ECP and non-ECP procedures had been successful in reducing postoperative IOP.

CONCLUSION

It can be deduced from this review, that all types of glaucoma can be treated efficiently with significantly higher success rates with ECP and ECP demonstrates lowest postoperative complications when compared to non ECP procedures. This review provides updated scientific evidence which caters to support clinical decisions for surgical treatment of glaucoma.

Endoscopic Pars Plana Vitrectomy in Patients With Open-Globe Injury and Corneal Opacity

Purpose: To determine the 1-year outcomes of endoscopic pars plana vitrectomy (EPPV) and its impact on the corneal transplantation rate in patients with open-globe injury (OGI) and corneal opacity. Methods: This retrospective cohort study collected data between December 2018 and August 2021. All EPPVs were performed at a level I trauma center. Inclusion criteria were adult patients with a history of OGI complicated by corneal opacification that prevented fundus visualization. The main outcome measures were the rate of successful retinal reattachment, final visual acuity (VA), and number of patients who had penetrating keratoplasty (PKP) within 1 year of the OGI. Results: Ten patients (3 women; 7 men) with a mean age of 63.4 ± 22.7 years (SD) met the inclusion criteria. The indications for EPPV were intraocular foreign bodies in 2 patients, dense vitreous hemorrhage in 3 patients (1 with a retinal tear; 1 with a choroidal hemorrhage), and retinal detachment in 5 patients. The final VA ranged from 20/40 to no light perception. All 4 repaired detachments remained attached after 1 year. Corneal opacity was treated with PKP in 3 patients. Conclusions: Results indicate EPPV can be a useful tool to treat posterior segment pathology in patients with a recent OGI and corneal opacity. EPPV can help address posterior segment disease and postpone corneal transplantation until the visual potential can be fully determined. Larger prospective studies are needed.

Effects of Image Processing Using Honeycomb-Removal and Image-Sharpening Algorithms on Visibility of 27-Gauge Endoscopic Vitrectomy

Endoscopic vitrectomy with small gauge probes has clinical potentials, but intraocular visibility is inherently limited by low resolution and dim illumination due to the reduced number of optic fibers. We investigated whether honeycomb-removal and image-sharpening algorithms, which enable real-time processing of live images with a delay of 0.004 s, can improve the visibility of 27-gauge endoscopic vitrectomy. A total of 33 images during endoscopic vitrectomy were prepared, consisting of 11 original images, 11 images after the honeycomb-removal process, and 11 images after both honeycomb-removal and image-sharpening procedures. They were randomly presented to 18 vitreous surgeons, who rated each image on a 10-point scale. The honeycomb-removal algorithm almost completely suppressed honeycomb artifacts without degrading the background image quality. The implementation of image-sharpening algorithms further improved endoscopic visibility by optimizing contrast and augmenting image clarity. The visibility score was significantly improved from 4.27 ± 1.78 for the original images to 4.72 ± 2.00 for the images after the honeycomb-removal process (p < 0.001, linear mixed effects model), and to 5.40 ± 2.10 for the images after both the honeycomb-removal and image-sharpening procedures (p < 0.001). When the visibility scores were analyzed separately for 10 surgeons who were familiar with endoscopic vitrectomy and 8 surgeons who were not, similar results were obtained. Image processing with honeycomb-removal and image-sharpening algorithms significantly improved the visibility of 27-gauge endoscopic vitrectomy.

Perioperative Nursing of Vitrectomy for Ocular Trauma under the Guidance of Ophthalmoscope

To explore the perioperative nursing methods and clinical effects of vitrectomy under ophthalmoscope in the treatment of severe ocular rupture, this study reviews the clinical effects of vitrectomy in the treatment of severe ocular trauma in China, analyzes the perioperative nursing of vitrectomy for ocular trauma under the guidance of an ophthalmoscope, and analyzes the importance of stage I debridement and suture, the choice of operation time, and the advantages of vitrectomy and perioperative nursing care. The retrospective analysis of these data shows that the clinical effect of peri-vitrectomy for ocular trauma under the guidance of an ophthalmoscope is accurate, and surgical treatment should be carried out as soon as possible according to the patient's condition, which can reduce the complications of suppurative ophthalmitis, eyeball atrophy, and vitreous rebleeding. Perioperative nursing intervention is beneficial to the recovery of visual acuity in patients with severe ocular rupture treated by vitrectomy under the ophthalmoscope, which is worthy of clinical promotion.

High-Resolution Ex-Vivo Imaging of Retina with a Laptop-Based Portable Endoscope

Purpose. Ophthalmic endoscopy is useful in vitreoretinal surgery with opaque anterior segments or anatomically challenging structures. However, standard ophthalmic endoscopy devices are usually large and costly. Thus, the development of a portable endoscope is necessary. Methods. The portable endoscope consisted of a probe, an illumination system, a high-resolution camera module, and a universal serial bus (USB). It was connected to a laptop and applied for intraocular imaging of porcine eyes in vitro. Basic parameters and pictures of the same tissue target were compared with those of the standard Endo Optiks E4 system. Results. The retinal images were displayed on the laptop screen, which clearly showed the overall appearance of the central and peripheral retina, and the details of the retinal vasculature and ciliary body. Compared with a standard endoscope, our portable endoscope is smaller and more affordable. It can be taken anywhere for intraocular imaging and vitreoretinal surgery. Conclusion. A laptop-based portable endoscope is a promising device in vitreoretinal surgery. It provides high-resolution images of intraocular tissues that should make a noticeable difference in intraocular surgery with disordered anterior segments. With its portability and high-resolution imaging, it may promote the application of endoscopes in ophthalmology.

Value of Ocular Endoscopy in Extraction of Intraocular Foreign Bodies of Cilia in Patients with Open Ocular Trauma

BACKGROUND The aim of this study was to analyze the value of ocular endoscopy in detecting and extracting intraocular cilia in patients with ocular trauma. MATERIAL AND METHODS We retrospectively analyzed data on identification and extraction of 46 intraocular cilia in 16 eyes with open-globe injury during endoscope-assisted vitrectomy. RESULTS A total of the 16 patients with open-globe injury were operated on from September 2002 to June 2019. The cornea in 14 eyes was cloudy. Two eyes had endophthalmitis and 13 eyes had retinal detachment. A total of 46 cilia were extracted through direct observation under the ocular endoscope during vitrectomy 1 to 68 weeks after injury. The number of cilia per eye varied from 1 to 10. Most of the cilia were located in or near the wound. Postoperative IOP was normal in 14 patients. The follow-up after surgery showed hypotony in only 2 eyes (7.2 and 5.8 mmHg, respectively). Compared with preoperative intraocular pressure, there was a statistically significant difference. The postoperative visual acuity improved in 12 eyes and remained unchanged in 3 eyes. The vision after surgery was significantly improved compared with that before surgery (P=0.006). The intraocular pressure increased significantly after operation (P<0.001). And no glaucoma or retinal detachment or endophthalmitis was found. No eyes needed additional vitreous surgery. CONCLUSIONS Ocular endoscopy allows surgeons to detect intraocular cilia that were no undetected by CT or B-ultrasound preoperatively in time and to extract them effectively. It improves performance of vitrectomy in the presence of a cloudy cornea and also prevents exogenous endophthalmitis. The vision of patients with ocular trauma was improved.