[The role of retinal microcirculation disorders in the progression of glaucomatous optic neuropathy]

[Optical coherence tomography and optical coherence tomography angiography for detecting glaucoma progression. Part 1. Study methods, measurement variability and the role of age-related changes]

This paper reviews the literature on the role of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in the diagnosis of glaucoma and considers the significance of evaluating retinal nerve fiber layer and ganglion cell complex in assessment of glaucoma progression, variability and reproducibility of the method, as well as the influence of age-related retinal changes on the results, analyzes the role of OCTA in glaucoma monitoring. Optical coherence tomography is a modern standard for glaucoma diagnosis and monitoring, and OCTA shows high potential as an auxiliary diagnostic tool.

[Optical coherence tomography and optical coherence tomography angiography for detecting glaucoma progression. Part 2. Clinical and functional correlations, monitoring of advanced glaucoma and limitations of the method]

The purpose of this study is to analyze the literature on the role of optical coherence tomography (OCT) and optical coherence tomography angiography (OCTA) in the diagnosis of glaucoma. This review considers the structural and functional correlations observed during the progression of glaucomatous optic neuropathy, as well as the capabilities of the method in late glaucoma, describes the strengths and weaknesses of OCT and OCTA, and pays particular attention to the role of OCT in assessing the effectiveness of treatment. Optical coherence tomography is the main method for determining the progression of glaucoma, which plays a key role in the choice of treatment algorithm. However, the use of OCT in far advanced glaucoma has certain particularities and limitations. OCTA can be helpful in overcoming this problem.

[Choroidal microvascular dropout as a biomarker of glaucoma progression in patients with diabetes mellitus]

PURPOSE

To study the occurrence, features of the development of choroidal microvascular dropout (CMvD) as a possible marker of the severity of the glaucoma process and to assess the impact of diabetes mellitus (DM) on the progression of these changes.

MATERIAL AND METHODS

The study included 258 eyes (258 patients), which were divided into groups: 1st - 58 patients (58 eyes) with stage I POAG and DM; 2nd - 50 patients (50 eyes) with stage I POAG; 3rd - 50 patients (50 eyes) with stage III POAG and DM; 4th - 50 patients (50 eyes) with stage III POAG; 5th - 50 patients (50 eyes) with DM. The observation period lasted 24 months. The occurrence and dynamics of the development of CMvD, their relationship with structural and functional indicators of the optic disc in the course of observation were evaluated in patients with POAG and DM.

RESULTS

CMvD was detected in stage I POAG in 17 eyes (34%), in patients with DM - in 27 eyes (54%), in the combined course of stage I POAG and DM - in 46 eyes (79.31%), in patients with stage III glaucoma - in 100% of cases. In patients with stage III glaucoma, the CMvD area indicators exceeded the values in other groups and practically did not differ regardless the presence of DM (0.59±0.13 mm², p=0.005) and its absence (0.57±0.14 mm², p=0.005). In the first year of follow-up, the increase in the area size of microvascular disorders in patients with POAG I was 5.88%, in comorbid patients - 3.84%, but by the end of the follow-up it increased by 19.23%, and in the group of patients with a high rate of progression - by 31.25%. Strong reliable correlations of CMvD with mean deviation (r=0.89) were revealed, as well as moderate correlations - with structural indicators of the optic disc (r=0.59) and with hemodynamic indicators (r=0.54 and r=0.52).

CONCLUSION

Development of CMvD is both a result of glaucomatous damage to the optic nerve and a consequence of a disruption of its hemodynamics at the level of the deep capillary plexus. The results of the study demonstrate the adverse effect of DM on the course of glaucoma, which determines the initiation of microvascular disorders that aggravate the severity of the glaucoma process and the rate of its progression.

[Effectiveness and safety of a hypotensive preservative-free drug in long-term therapy of glaucoma]

PURPOSE

To investigate the condition of the ocular surface and the effectiveness of Taflotan for long-term therapy in patients with newly diagnosed primary open-angle glaucoma in real clinical practice.

MATERIAL AND METHODS

This publication presents data form a retrospective observational study that analyzed newly diagnosed glaucoma patients that have been using 1 drop/day of Taflotan in the evening for 12 months. All patients were examined at baseline, and after 1 month and 12 months of treatment, recording intraocular pressure (IOP), retinal photosensitivity indicators (MD, PSD), thickness of the retinal nerve fiber layer (RNFL), and assessing the condition of the ocular surface by Schirmer test, tear breakup time (TBUT), ocular surface disease index (OSDI) questionnaire, as well as measurement of the lacrimal meniscus height and corneal staining with lissamine green.

RESULTS

IOP effectively decreased in all patients using Taflotan, reaching the target pressure by 1 month after therapy initiation. IOP decreased from 25±4 mm Hg at baseline to 17±3mm Hg after 1 month with further decrease down to 16±3 mm Hg after 12 months of therapy. Retinal photosensitivity (MD and PSD) and RNFL thickness did not differ from baseline, and correlated to glaucoma stage. The indicators of the condition of the ocular surface had no significant differences between the baseline, 1-month and 12-month time points.

CONCLUSION

Taflotan effectively decreases IOP in newly diagnosed glaucoma patients, maintains stable automated perimetry indices and RNFL thickness, and does not affect the ocular surface throughout 12 months of therapy.

[Examination of patients with glaucoma during the COVID-19 pandemic]

PURPOSE

To evaluate the efficacy of the optimal examination technique for patients with glaucoma during the COVID-19 pandemic that includes one of the safest methods of tonometry [transpalpebral tonometry (TPT), contour dynamic tonometry (CDT) and Icare rebound tonometry (RBT)] in combination with spectral domain optical coherence tomography (SD-OCT) and optical coherence tomography angiography (OCTA).

MATERIAL AND METHODS

The study included 65 patients with primary open-angle glaucoma (POAG) who sought medical aid at the Ophthalmological Center of FMBA during the COVID-19 pandemic; they were examined using three tonometry methods: RBT, TPT and CDT. All patients underwent central corneal thickness measurement, perimetry, OCT and OCTA with assessment of vessel density (VD) of the superficial plexus in the macula (whole image macula) and peripapillary retina (PPR).

RESULTS

High correlation was found between the results obtained with RBT, TPT and CDT. None of the methods showed a correlation between IOP and corneal thickness. The correlations between IOP and OCTA parameters were obtained: IOP_TPT and VD_PPR in the inferior temporal sector (r= -0.386, p=0.027), IOP_RBT and VD whole image macula (r= -0.69, p=0.019), and in the macula inferior hemisphere (r= -0.75, p=0.008), as well as between the ocular pulse amplitude (OPA) and VD in the macular inferior hemisphere (r=0.380, p=0.039). The OCTA parameters had a moderate, but significant correlation with the perimetric indices.

CONCLUSIONS

Tonometry methods (TPB, CDT and RBT) exhibit high correlation with each other and no correlation with corneal thickness. IOP parameters measured by different methods, especially using the Icare tonometer, correlate with OCTA parameters, and the latter - with perimetric indices. The combination of these tonometry methods with SD-OCT and OCTA is optimal for examining patients during the pandemic.