Indian Journal of Ophthalmology最新文献

Background: Finding a retinal break which is responsible for retinal detachment is a critical step in the surgical treatment of this condition. In spite of improvement in visualization systems in pars plana vitrectomy, identifying the break which is the source of subretinal fluid (SRF) could pose a challenge, especially in complex retinal detachments or re-detachments with extensive laser scars.

Purpose: The current technique of break identification involves direct detection of the break via peripheral indentation or using perfluorocarbon liquid (PFCL) to displace SRF from the posterior retina to the periphery and visualizing the proteinaceous SRF egress from the retinal break. In retinal detachments, if no peripheral breaks are visualized, surgeons tend to make a posterior draining retinotomy and drain SRF, the necessity of which can be confirmed after subretinal brilliant blue green (BBG) dye injection. In addition, in already vitrectomized eyes where it can be difficult to identify SRF egressing via the break, subretinal BBG dye provides a color contrast that enhances break visualization.

Synopsis: A method to identify these occult breaks was required, which is described in this video. Hence, the idea of BBG dye injection into the subretinal space with a 41G subretinal needle was thought of. PFCL would be placed over the posterior pole, which would displace the dye to the periphery, and this would disperse out into the vitreous cavity into a blue plume via the break, thereby leading to its identification.

Highlights: Subretinal dye injection is useful for occult retinal break detection as it provides a color contrast. A posterior draining retinotomy can be avoided. It is also useful in recurrent retinal detachments. We describe the use of BBG, which is the least toxic dye available, and report the use of this technique in Indian eyes.

Video link: https://youtu.be/JGXQjNV9asw.

Purpose: To develop and validate MNREAD acuity charts in the Thai language (MNREAD-TH).

Methods: In total, 180 Thai sentences were generated using words specific to the primary 1-3 students. Each sentence contained 60 characters divided into three lines with even left and right margins and was evaluated by instructors in the education program in Thai. The selected 118 sentences were tested in 20 adults and 20 children by measuring reading time and recording the errors. Sentences with extremely high or low mean reading speeds were excluded. The remaining sentences were selected for contributing to the MNREAD-TH charts. For validation, the charts were tested in another 20 normal-sighted adult groups.

Results: In total, 118 sentences were tested on 20 adults (range: 23-58 years) and 20 primary school students (age: 8-9 years). The mean (SD) reading speeds in adult and children's groups were 134.09 (12.45) and 71.33 (10.77) words/min (wpm), respectively. After removing the sentences that deviated by ±1 SD from the mean reading speed, repeatedly had difficulty words, and had low subjective scoring, 60 matched sentences between the groups were selected to develop three versions of the MNREAD-TH chart. The intraclass correlation coefficients between charts were 0.85 for reading acuity, 0.94 for maximum reading speed, and 0.79 for critical print size.

Conclusion: The MNREAD-TH charts can be reliably used for evaluating reading performance in Thai people for both children and adults with either normal sight or low vision. These charts are standardized and helpful in clinical trials involving reading.

Context: Lighting conditions significantly influence visual acuity (VA), visual function, and quality of life. Previous research highlighted a correlation between luminance and VA but left a gap in understanding the impact of surrounding luminance. This study focused on investigating the effects of both central and peripheral luminance on VA.

Purpose: This study aimed to investigate the influence of both central and surrounding luminance on VA through distance VA measurements.

Settings and design: A dual-component lighting system was utilized, comprising a self-illuminated ETDRS chart and a skyLED system for consistent surrounding illumination. Two experimental setups were conducted: the first varied the central luminance (25 ± 2-341 ± 10 cd/m²), while the second maintained a constant central luminance (150 ± 5 cd/m²) and varied the surrounding luminance (4 ± 2 cd/m² OFF-105 ± 10 cd/m² ON).

Methods: Sixty-six participants with refractive errors between 0.0 D and -2.75 D were tested under various lighting conditions. Both uncorrected refractive error (URE) and corrected refractive error (CRE) eyes were evaluated.

Statistical analysis used: Paired t-tests were used to evaluate the statistical significance of differences in VA scores.

Results: Experiment 1 demonstrated a significant increase in VA scores, with mean improvements of -0.120 LogMAR for URE eyes and -0.073 LogMAR for CRE eyes as chart luminance increased from 26 cd/m² to 153 cd/m². Experiment 2 further showed a notable improvement in VA scores under varied surrounding luminance conditions, with mean improvements of - 0.118 LogMAR for URE eyes and -0.073 LogMAR for CRE eyes as luminance increased from 4 cd/m² to 102 cd/m².

Conclusions: This study emphasizes the significant impact of both central and peripheral luminance on VA. The introduction of the skyLED lighting system underlines the importance of optimal lighting for visual performance.

Purpose: To study the morphological and histological characteristics of the fibrous capsule formed around a novel biodegradable glaucoma drainage device (GDD) implant made of oxidized regenerated cellulose (ORC) after 1 and 3 months of its implantation.

Methods: It was a prospective, interventional, preclinical experimental study using New Zealand white rabbits. All animals underwent GDD implantation with a novel biodegradable device. The device's body was made of ORC and attached to a silicone tube, connecting the body to the anterior chamber. Histopathology (hematoxylin and eosin/Masson's trichrome staining) and immunohistochemistry (Alpha-Smooth Muscle Actin expression) characteristics of the bleb formed around the novel device were noted at 1 and 3 months.

Results: One month post implantation, the biodegradable material produced a significant foreign body type of reaction evidenced by the exuberant infiltration by macrophages, lymphocytes, and multinucleated giant cells. The granulomatous response subsided by 3 months with disorganized collagen deposition on Masson's trichrome staining. The silicone tube was an internal control, and histopathology demonstrated well-organized collagen deposition around it at 3 months. Immunohistochemistry for α-smooth muscle actin also demonstrated more myofibroblast transformation at the site of the tube than the biodegradable implant.

Conclusions: Our results indicate that the tissue response around a biodegradable GDD was different from the response to conventional devices. A diffuse, loose vascularized mesh was observed to develop, which may be more compatible with sustained IOP control over a longer period, in contrast to the usual thick and dense capsule formed around the non-biodegradable devices.

To propose a needle aspiration technique for the surgical removal of orbital cavernous hemangioma. In this retrospective case series, we enrolled 13 patients with orbital cavernous hemangioma, who underwent excisional surgery assisted with needle aspiration technique from June 2013 to April 2022. Preoperative symptoms, clinical examination, and imaging features were recorded. Surgical outcomes, including the improvement of visual acuity, proptosis, and ocular motility, were assessed. Postoperative complications were also reported. There were 11 female and two male patients, with a mean age of 50.2 ± 8.0 years (range: 38-61 years). The most common symptom was proptosis (12 cases, 92%), followed by blurred vision (6 cases, 46%). The diameter of the lesions was between 1.8 and 3.2 cm on preoperative imaging. The surgical approaches included sub-brow orbitotomy in 11 patients and the inferior transconjunctival approach in two cases. All the tumors were removed successfully after needle aspiration of 1-3 cc of intralesional blood to reduce the tumor size. Preoperative proptosis, blurred vision, and diplopia improved after the surgery in all cases. There were no serious complications or recurrence of orbital hemangioma. The study presented an effective application of the needle aspiration technique in the surgical management of orbital cavernous hemangioma. Such an innovative method can bring significant benefits, especially for those with large cavernous hemangioma within the deep orbital region.

Purpose: To describe the surgical technique using a 10/14 French silicone urinary catheter as a novel tissue expander for repair of defects after removal of eyelid tumors. This device recruits additional tissue by tissue expansion for repair of large eyelid defects.

Methods: A prospective noncomparative, interventional case study was conducted over a period of 3 years in which 30 patients were enrolled. All the 30 patients were selected for upper or lower lid Tenzel rotational flap after removal of large malignant tumor, using the tissue expander.

Results: A 10/14-French silicone urinary catheter was placed in the periocular region and expanded by graded inflation with normal saline to a total volume of 10 or 14 ml, respectively, over a period of 3 days. On the fourth day before the planned surgery, the catheter balloon was deflated and a modified Tenzel rotational flap was performed to close the defect. Postoperative blink reflex was preserved. There were no cases of wound dehiscence. There was a significant reduction of incision length in upper and lower lid reconstruction with modified Tenzel flap reconstruction.

Conclusion: This approach allows for temporary tissue expansion, permitting the closure of large eyelid defects, typically not possible with a conventional Tenzel flap. This also provides excellent functional outcomes without closing patients' eyelids (which limits vision for weeks to months) as is typical of other reconstructive modalities (e.g. Cutler Beard procedure). The device is cost-effective and readily available. The authors believe it is an excellent alternative in the developing world where access to more expensive options is limited.

Purpose: In this study, we aimed to compare closure of the incision for external dacryocystorhinostomy (ext-DCR) by suturing with 6-0 Prolene versus closure with 2-octyl cyanoacrylate and assess the results in terms of the aesthetic and functional aspects of the scar, operating time, postoperative symptoms and complications, and the economic cost of the two techniques.

Methods: Sixty-three patients with distal lacrimal obstruction and indication of ext-DCR were initially enrolled in a longitudinal prospective cohort study. Patients underwent ophthalmologic evaluations including lacrimal probing, external examination with photograph, measurement of the surgical wound, timing the cutaneous closure phase of the surgery, recording postoperative wound pain using visual analog scale (VAS), and recording the patient's and clinician's subjective satisfaction with the scar using Patient and Observer Scar Assessment Scale (POSAS) at 6 months postsurgery. The 63 eyes were divided into two groups: the wounds in group 1 were closed with 6-0 Prolene using continuous locking suture and the wounds in group 2 were closed with 2-octyl cyanoacrylate.

Results: There was no difference in baseline characteristics (age, sex, and race), and no statistically significant differences were found in wound length, POSAS score, VAS score, or serious complications of the wound between the two groups. There were differences in surgery time and economic cost for group 2 compared to group 1 of -2.39 min and -€5.37/operation, respectively.

Conclusion: This is the first study in the literature that compares 6-0 Prolene versus Dermabond ® . The latter one presents advantages compared to Prolene, given that it reduces the length of surgery, reduces costs, and allows for greater flexibility in postoperative follow-up visits.