Diabetic iris neovascularization

Study on the correlation between iris blood flow, iris thickness and pupil diameter in the resting state and after pharmacological mydriasis in patients with diabetes mellitus

BACKGROUND

To investigate whether iris blood flow and iris thickness at the iris smooth muscle region affect the pupil diameter at rest and after drug-induced mydriasis in patients with type 1 diabetes mellitus (T1DM) and type 2 diabetes mellitus (T2DM).

METHODS

T1DM patients and healthy children were recruited from the SCADE cohort. T2DM patients and healthy adults were recruited from patients undergoing cataract surgery at Shanghai General Hospital. Iris vessel density, pupil diameter (PD) and iris thickness were measured in both the resting and drug-induced mydriasis states. Iris vessel density was measured by optical coherence tomography angiography (OCTA), PD was measured by a pupilometer, and iris thickness at the iris smooth muscle regions were measured using anterior segment optical coherence tomography (AS-OCT).

RESULTS

The study included 34 pediatric T1DM patients and 50 adult T2DM patients, both groups without diabetic retinopathy, and age-sex-matched healthy controls. At baseline, T1DM children and healthy children showed no differences in iris blood flow, iris thickness, or PD. However, the adult T2DM group exhibited higher vessel density at the pupil margin, thinner iris thickness at the iris dilator region, and smaller PD compared to healthy adults, with these differences being statistically significant (P < 0.05). After pupil dilation, there were no changes in iris blood flow and PD in the T1DM group compared to healthy children, whereas the T2DM group showed a significantly smaller PD compared to healthy adults. Multivariate regression analysis revealed that in the T2DM group, glycated hemoglobin was an independent factor of PD after dilation (β=-0.490, p = 0.031), with no such factors identified in the T1DM group.

CONCLUSION

The insufficiently dilated pupil diameter after drug-induced mydriasis is correlated to the level of glycated hemoglobin among T2DM patients.

TRIAL REGISTRATION

The registration number on the clinical trial website was NCT03631108.

[Neovascular Glaucomas - Pathogenesis, Diagnosis, Treatment and Prophylaxis]

Neovascular glaucoma (NVG) is a severe potentially blinding disease, which represents one of the most common types of secondary glaucomas. The majority of cases are caused by ischemic retinal conditions such as diabetic retinopathy, central retinal vein occlusion or ocular ischemic syndrome. If appropriately diagnosed and treated, ideally the development of NVG can be prevented. Since treatment gets increasingly challenging as the disease progresses, early diagnosis is of utmost importance. In this review pathogenesis, diagnosis, treatment and prophylaxis are discussed extensively. A focus is put on the consecutive stages through which the disease progresses and how to diagnose and differentiate them. Ultimately a stage adapted therapy approach is detailed, consisting of the three blocks: 1. treatment of the underlying disease/retinal ischemia, 2. adjunctive medical therapy (anti-VEGF) and 3. therapy of the elevated intraocular pressure.

[Secondary open-angle glaucoma: pseudoexfoliative glaucoma, pigmentary glaucoma and neovascular glaucoma]

Secondary open-angle glaucomas are a heterogeneous group of diseases in which a variety of pathophysiological mechanisms result in an elevation of intraocular pressure. This article is the first part of a review of the more common forms of secondary open-angle glaucomas. The pathogenesis, characteristic clinical findings and treatment of pseudoexfoliative glaucoma, pigmentary glaucoma and neovascular glaucoma are discussed. An emphasis is placed on the differences in treatment compared to primary open-angle glaucoma and prophylactic treatment approaches are explained where possible.

Visual Outcomes in Eyes With Neovascular Glaucoma and Anterior Segment Neovascularization Without Glaucoma

PURPOSE

To find predictive factors of neovascular glaucoma (NVG) development in eyes with anterior segment neovascularization without glaucoma (ASNVWG), and poor visual outcomes in eyes that have already developed NVG.

DESIGN

Retrospective, clinical cohort studies.

METHODS

A retrospective chart review was performed on 106 eyes of 94 patients with ASNVWG and 245 eyes of 225 patients with NVG. Measured outcomes included the development of NVG at any time point of the disease for the ASNVWG arm, and a visual acuity of ≤20/200 at 6 months after initial presentation for the NVG arm.

RESULTS

Overall, 25% of ASNVWG eyes progressed to NVG. Progression was associated with retinal vein occlusion (RVO) (P < .01), lower median presenting BCVA (P < .01), and concurrent traction retinal detachments (TRDs) (P = .025). Sixty-eight percent of NVG eyes had a BCVA of ≤20/200 by 6-month follow-up, which was associated with RVO (P = .005), vitreous hemorrhage on presentation (P = .001), and no panretinal photocoagulation (PRP) treatments (P < .001). BCVA >20/200 at 6 months was associated with ≥1 PRP or intravitreal bevacizumab (IVB) treatment within 1 week of presentation or ≥3 PRP or IVB treatments overall (P < .001).

CONCLUSION

RVO, presenting visual acuity, and concurrent TRD are risk factors for NVG in eyes with ASNVWG. In eyes with NVG, RVO and concurrent vitreous hemorrhage are risk factors for ≤20/200 vision at 6 months, whereas treatment with ≥1 PRP or IVB within 1 week of presentation, or ≥3 treatments of PRP or IVB within 6 months are protective.

Sekundärglaukome im Rahmen retinaler Erkrankungen

Zusammenfassung: Eine Vielzahl retinaler Erkrankungen kann zur Entwicklung eines Glaukoms führen. Die häufigste Form dieser Sekundärglaukome sind die Neovaskularisationsglaukome, die den Hauptteil dieser Übersicht bilden. Dabei handelt sich um ein schwerwiegendes Krankheitsbild, dass in mehreren Stadien verläuft, wobei die Prognose mit zunehmendem Stadium ungünstiger und die Therapie herausfordernder wird. Neben Pathogenese und Diagnostik wird daher ein Schwerpunkt wird auf die Früherkennung und eine an das jeweilige Krankheitsstadium angepasste Therapie gelegt. Auch seltenere Sekundärglaukome im Rahmen intraokularer Tumore sowie Glaukome assoziiert mit einer Netzhautablösung (Schwartz-Matsuo Syndrom) und Glaukome, die im Spätverlauf nach unkomplizierter Vitrektomie auftreten, werden in dieser Übersicht diskutiert. Abstract: A variety of retinal diseases can lead to the development of glaucoma. The most common type of these secondary glaucomas is neovascular glaucoma (NVG), which constitutes the main subject of this review. NVG is a severe condition with a poor prognosis. Treatment gets increasingly challenging as the disease progresses. Thus emphasis is put on early diagnosis and an stage adjusted therapy. Other less frequent secondary glaucomas, such as glaucomas due to intraocular tumors or associated with retinal detachment (Schwartz-Matsuo syndrome) and late onset open-angle glaucomas after uncomplicated vitrectomy are covered.

Management of Secondary Angle Closure Glaucoma

Secondary angle closure glaucomas are a distinct entity from primary angle closure glaucoma (PACG). Unlike PACG, secondary angle closure glaucoma's have an identifable contributory factor/s for angle closure and obstruction of aqueous fow which is usually unrelieved by iridotomy. The treatment of each type of secondary angle closure glaucoma is varied, so identification of the primary cause aids in its effective management. How to cite this article: Annadurai P, Vijaya L. Management of Secondary Angle Closure Glaucoma. J Current Glau Prac 2014;8(1):25-32.

Evidence-based recommendations for the diagnosis and treatment of neovascular glaucoma

PURPOSE

To succinctly update information on the pathogenesis, etiology, diagnosis, and treatment of neovascular glaucoma based on a systematic review of available literature and to provide summary recommendations rated for their importance to clinical outcome.

CLINICAL RELEVANCE

Neovascular glaucoma is a devastating ocular disease that often results in loss of vision. The current standard of care includes retinal ablation and control of increased intraocular pressure with medical and surgical therapy. LITERATURE REVIEW METHODOLOGY: The authors conducted a MEDLINE literature search of articles published in English from 1966 to the present. Each article reviewed was rated as to the strength of evidence it provided, and summary ratings for the strength of evidence supporting clinical recommendations were generated.

RESULTS

Level A (most important to patient outcome) recommendations for the diagnosis of neovascular glaucoma include a high index of suspicion, a full ocular examination including undilated gonioscopy, and pupil examination. In regard to treatment, Level A recommendations include treatment of the underlying disease origin, complete panretinal photocoagulation (if retinal ischemia is a factor), and medical control of both elevated intraocular pressure and inflammation. Level B recommendations (moderately important to patient outcome) encompass glaucoma surgery to control intraocular pressure when medical therapy is unsuccessful, although the ideal surgical procedure is unknown. Currently, trabeculectomy with antimetabolite therapy, aqueous shunt implants, and diode laser cyclophotocoagulation are the preferred surgical treatment options.

CONCLUSIONS

The current literature on neovascular glaucoma has few articles that provide strong evidence in support of therapy recommendations (level I). Future research studies are needed to address areas in which the current evidence is moderately strong (level II) or weak, consisting only of a consensus of expert opinion (level III). Whenever practicable, these studies should be prospective, randomized clinical trials.