PURPOSE. To determine predictors of hypotensive efficacy of lens extraction (LE) with intraocular lens implantation in patients with primary angle closure (PAC) using machine learning.

MATERIAL AND METHODS. A prospective study included 30 patients with PAС, aged 41 to 80 years, who underwent LE. The observation period was 1 month. All subjects underwent Swept Source optical coherence tomography (SS-OCT). The analyzed parameters included 37 parameters such as spherical equivalent (SE), corrected distance visual acuity (CDVA), intraocular pressure (IOP), Shaffer angle opening degree, lens opacity, choroidal thickness in the macula, axis length (AL), anterior chamber depth (ACD), lens vault (LV), iris curvature (ICurv) and thickness (IT750), anterior chamber angle opening distance (AOD), iridotrabecular space area (TISA). As the success of treatment, the value of the decrease in intraocular pressure (DIOP) after the intervention relative to the initial one was taken. Along with standard methods of descriptive statistics, machine learning based on multivariate statistical data analysis were used.

RESULTS. After treatment, IOP decreased from 25.5±2.3 mmHg up to 17.2±1.19 mmHg (p=0.000) against the background of a statistically significant decrease in the number of medicines (from 0.63±0.49 to 0.07±0.25, p=0.001). Predictors of DIOP were: advanced age (B-coefficient=0.235), male gender (B=-0.243), presence of early cataract (B=0.274), low CDVA (B=-0.06), high values of preoperative IOP (B=0.267), SE (B=0.437), LV (B=0.237) and ICurv (B=0.260 in the nasal and 0.232 in the temporal sectors, respectively), as well as low values of IT750 (B=-0.142 and -0.146 in the same sectors, respectively), ACD (B=-0.367), AL (B=-0.487), anterior chamber angle profile parameters.

CONCLUSION. Predictors of the hypotensive effect of LE identified using the machine learning include the advanced age, male gender, high initial IOP, spherical equivalent and lens vault, the presence of early cataract, steep and thin iris, shallow anterior chamber, short axis length and narrow anterior chamber angle.

PURPOSE. To evaluate the anatomical-topographic parameters of the anterior chamber of the eye before and after micropulse cyclophotocoagulation (mCPC) in patients with refractory glaucoma in pseudophakic and phakic eyes.

METHODS. The study included 60 patients (62 eyes) with moderate (7 eyes) and advanced (55 eyes) refractory glaucoma. Study groups were formed as follows: the 1st group consisted of 31 pseudophakic eyes (32 patients), the 2nd group included 31 phakic eyes (30 patients). All patients underwent mCPC according to a modified technique. To assess anatomical parameters patients underwent optical coherence tomography of the anterior segment (AS-OCT). Anterior chamber angle (ACA) and anterior chamber depth (ACD) were measured at specific follow-up time points after mCPC.

RESULTS. Hypotensive effect by the end of 12-month follow-up was achieved in the patients of the first group in 83.1% of cases, in the second group — in 80.6% of cases (p<0.05). According to OCT findings, anterior chamber depth in patients with phakic eyes during the 12-month follow-up remained the same as before surgery — 2.43±0.21 (mm). In the other group with pseudophakic eyes, anterior chamber depth also did not change during the observation period, with an average value of 3.27±0.12 (mm). No significant changes (p>0.05) were found in the irido-corneal angle measurements in the 4 meridians over the entire follow-up period in both groups.

CONCLUSION. Micropulse cyclophotocoagulation performed at fluence rate F=121 J/cm² does not result in changes of structures of the anterior segment of the eye. The stability of anterior chamber anatomy as well as the absence of postoperative complications in early and longterm follow-up proved the minimal traumatic effect of this surgery in patients with refractory glaucoma. 

PURPOSE. Improving the results of the operation and achieving its reliability in secondary glaucoma, including refractory glaucoma, can be done using a non-biodestructible allograft drainage with spongy structure fabricated by Alloplant^® technology.

METHODS. Experimental and morphological studies conducted in the Russian Eye and Plastic Surgery Center showed that the allogeneic spongy biomaterial used for anti-glaucoma sponge drainage surgery is gradually replaced by loose tissue with a porous structure, similar to trabecular, forming a new drainage system. During the operation, the proximal part of the drainage is inserted through the excised drainage zone in the anterior chamber angle (ACA). The distal part is tucked into the suprachoroidal space through a linear incision in the scleral bed.

RESULTS. The newly created topography of the ACA after sponge drainage operation with the use of allogeneic biomaterial features not only the expansion of the ACA profile, but also the replacement of the excised part of the drainage zone with biomaterial after sinus trabeculectomy (STE) and elimination of retention of the intraocular fluid (IOF) outflow. Ultrasound biomicroscopy (UBM) performed at various times after antiglaucoma surgery showed that the microtubule system preserved. Optical coherence tomography (OCT) of the ACA demonstrates the location of the drainage in the long-term follow-up.

CONCLUSION. Antiglaucoma operation with the use of allogeneic biomaterial with spongy structure promotes the formation of trabecula-like tissue in the ACA, eliminates retention of IOF outflow, and reduces the risk of scleroscleral and sclero-conjunctival adhesions.

PURPOSE. To evaluate the clinical effectiveness and safety of using a fixed combination — hypotensive drug Brimonidine Duo (brimonidine tartrate 2 mg/mL + timolol maleate 5 mg/mL) to reduce intraocular pressure in patients with advanced stages of primary open-angle glaucoma (POAG) in cases when achieving target pressure failed after laser micropulse transcleral diode laser cyclophotocoagulation (mCPC).

METHODS. MCPC was performed with individually chosen parameters in 100 patients (104 eyes) aged 35 to 86 with POAG, of them 54.17% were men and 45.83% were women. The follow-up period lasted 3 months, the results were evaluated on the 1st, 7th and 14th days, then after 1 and 3 months. In 23.08% of cases (24 patients) subjects were prescribed antihypertensive combination drug Brimayza Duo due to intraocular pressure (IOP) remaining uncompensated.

RESULTS. The average IOP level after 7 days was 23.54± 4.8 mm Hg. After 3 months, IOP values were 18.11±2.04 mm Hg, which is 4–5 mm Hg lower than in the early postoperative period. After 30 days of follow-up, an additional antihypertensive drug Latanoprost 0.005% was added for 5 patients (20.83%). Repeated surgery was recommended and performed in 4 patients (16.67%), of which 1 patient underwent surgical intervention of the penetrating type, 3 patients underwent repeat mCPC with individually chosen parameters.

CONCLUSION. MCPC is a safe and effective tool for reducing intraocular pressure in patients with advanced stages of POAG. The noninvasive nature of this technique makes it possible to speed up the recovery time after surgery, as well as reduce the number of postoperative complications. Among patients who failed to achieve target pressure after surgery, the use of Brimayza Duo was effective in 62.5% of cases.

PURPOSE. To determine the age-related increase in lens thickness (LT), decrease in anterior chamber depth (ACD) and anterior chamber angle (ACA) in patients with short axial length (APA) of the eyes.

METHODS. The study included 100 patients (200 eyes) with short AL (23 mm or less), with a transparent lens or with initial stage of age-related cataract: 46 men and 54 women, aged 19 to 85 years. The LT and ACD, ACA parameters were assessed using optical coherence tomography.

RESULTS. In the total population of patients, LT increased by an average of 32 μm per year. At the same time, ACD and ACA decreased by an average of 14 µm and 0.3° per year, respectively (p<0.001). In men, LT increased by 35 μm per year, while in women it increased by 29 μm per year, the difference was not statistically significant (p=0.071). But the decrease in ACA in men averaged 0.38° per year, while in women it was 0.23° per year, this difference was statistically significant (p=0.003). In addition, the rate of decrease in the ACD in men and women also differed statistically significantly: 18 µm versus 11 µm per year (p=0.018).

CONCLUSION. 1. According to our data, the annual increase in LT in eyes with short AL averages 32 μm, the decrease in ACD and ACA is on average 14 μm and 0.3° per year, respectively.

2. We did not find a statistically significant gender difference in the rate of annual increase in LT, although the rate of decrease in ACA and ACD in men turned out to be statistically significantly higher.

3. The obtained data on the annual changes in such morphometric parameters as LT, ACA and ACD in eyes with short AL are key in the formation of primary angle-closure glaucoma (PACG). It may allow a more precise prediction of the timeline of an increased risk of PACG in each particular case.

PURPOSE. To study the influence of the illuminance level of test objects on the resolution of the visual analyzer in patients with primary open-angle glaucoma (POAG) and age-related macular degeneration (AMD), and assess the possibility of using the obtained results for early diagnosis of these eye diseases.

METHODS. Visual acuity (VA) under controlled illumination conditions (from 50 to 400 lx) of test objects was assessed using the developed device in three groups: in 50 healthy subjects aged 37.08±10.19 years without ophthalmic pathology (group A), in 50 patients with early (Ia and IIa) stages of POAG aged 47.16±8.28 years (group B) and 50 patients aged 46.08±4.56 years (group C) with dry form of AMD (initial stage).

RESULTS. With an increase in the illumination of test objects (IT) from 50 to 400 lx, the VA of healthy individuals significantly increases on average by δ=0.32 (from 1.0±0.22 to 1.32±0.24, p<0.01), while in POAG the increase in VA with an increase in IT is much less pronounced, averaging δ=0.12 (from 0.9±0.20 to 1.02±0.26, p<0.05). At the same time, starting from IT 150 lx and above, the differences between the values of VA in the control group and in the group of patients with POAG of the initial stages become significant (p<0.05). VA of patients with AMD with increasing IT practically does not change, remaining at a stable level: δ=0.04 (from 0.76±0.20 to 0.80±0.26, t=0.66, p>0.5). At the same time, the VA values in this group of patients for each illumination level are significantly lower (p<0.05) than the corresponding VA values in the control group (group A).

CONCLUSION. The revealed regularities can be used for early diagnosis of the pathological process: an increase in VA at the maximum level of IT relative to the initial value by less than δ≤0.2 indicates pathology of the optic nerve (POAG), and the absence of significant changes in VA with an increase in IT (minimum values of δ) is characteristic of the pathological process in the macula (AMD).

PURPOSE. To evaluate the effect of surgical treatment of secondary glaucoma with subsequent end-to-end keratoplasty in a patient with aphakia, operated retinal detachment and condition after intrastromal keratoplasty.

METHODS. A patient with secondary refractory glaucoma against the background of aphakia, a biopolymer implant in the corneal stroma, an inflammatory reaction to multiple surgical interventions (formation of anterior synechiae), operated retinal detachment was examined in the S.N. Fedorov National Medical Research Center "MNTK "Eye Microsurgery" in Moscow. The following treatment was performed: implantation of Ahmed valve drainage and pene-trating keratoplasty with implant removal.

RESULTS. On the second day after implantation of Ahmed valve drainage on the right eye, intraocular pressure was normal in palpatory examination, the drainage tube in the anterior chamber was in the correct position. Three months after the operation, there were no complaints, intraocular pressure was normal in palpatory examination, there was a decrease in corneal edema. Penetrating keratoplasty was performed four months after the implantation of Ahmed valve drainage. On the second day after the operation, hypotension was noted with palpatory measurement of intraocular pressure, which persisted for five days. At patient discharge, the graft was adapted, the sutures were consistent, normal pressure with palpatory examination. During the observation period of up to three months, visual acuity increased to 0.1.

CONCLUSION. To prolong the hypotensive effect and minimize intra- and postoperative complications in order to achieve the highest possible visual functions before performing optical reconstructive surgery, it is advisable to perform an anti-glaucoma intervention. In secondary refractory glaucoma caused by various factors, the choice of surgical treatment is always individual and depends on the severity of anatomical changes, the experience and capabilities of the surgeon, and often requires multi-stage treatment with continuous observation.

Nowadays methods of standard and non-standard computerized perimetry using stationary devices are widely used in functional screening of glaucoma. The information about new portable devices for perimetry has appeared in foreign literature in recent years, describing such advantages as economic availability, autonomy and mobility, which open up new possibilities for their use. New possibilities include cloud storage of data, the use of telemedicine technologies, artificial intelligence, examination of patients with disabilities, including those who are bedridden, as well as examination outside of medical institutions. All of this can allow glaucoma patients to receive ophthalmic care when in-person visits are unavailable, including social distancing needed during a pandemic or quarantine. This review of the literature describes the latest portable devices and applications for perimetry, attempts to classify them according to similar parameters, and assesses their advantages and disadvantages, as well as the prospects for their use in functional screening of glaucoma.

Glaucoma continues to be the leading cause of irreversible blindness worldwide. The main proven risk factor is elevated intraocular pressure. But questions remain on the impact of various somatic diseases and their correction on the course of glaucoma. This review provides information on the metabolic syndrome and considers some of its components and their correction in patients with glaucoma.

The metabolic syndrome includes arterial hypertension, diabetes mellitus, dyslipidemia and obesity. The presented experimental and clinical studies show that the components of the metabolic syndrome correlate with glaucoma. Such components of the metabolic syndrome as arterial hypertension and diabetes mellitus are without doubt risk factors for the development of glaucoma. The opinions of researchers regarding whether obesity and dyslipidemia can also be considered risk factors are ambiguous. Recently, however, interest in them has increased due to in-depth study of the microbiome, since changes in it play a certain role in the development of neurodegenerative diseases of the central nervous system and the retina. Several studies have noted that being overweight and obese is associated with a risk of developing glaucoma. Indicators of lipid metabolism also showed a certain relationship with the risk of developing glaucoma. Treatment of lipid metabolism disorders commonly involves the use of statin drugs. Recent studies show that they may have more than just a hypolipidemic effect. A number of studies has demonstrated that the use of statins improves blood circulation and has a neuroprotective effect.

The analysis of trends in the surgical treatment of primary open-angle glaucoma (POAG) allows assessing changes in the indications for surgical treatment, the number of glaucoma surgery and their modifications, as well as the demographic characteristics of patients, duration of preoperative therapy and the effectiveness of treatment.

The results indicate that over the past 20 years in the Russian Federation there was a shift towards an increasingly long-term therapeutic strategy used before the surgical stage of treatment, and, in general, a decrease in the number of performed glaucoma surgeries. There is much concern about late surgical treatment, which is confirmed by the established increase in the age of first-time operated patients, and the tendency to increase the number of operations at a far advanced stage of the disease. Most of the published studies on the postoperative hypotensive efficacy of surgery are of limited duration, which does not allow an adequate assessment of the results of treatment. Early appointment of medical hypotensive therapy after surgical intervention indicates a low interaction between outpatient and inpatient specialists, which hinders the possibility of early correction of postoperative problems. The recent increase in the number of scientific works, especially patents, focusing on the search for new technologies that can be implemented in glaucoma surgery, the development of modern drainage devices and the methods for prolonging the hypotensive effect after surgery gives a reason for optimism. The performed analysis dictates the need to develop and implement measures aimed at clearly defined indications for timely surgical treatment and creation of conditions for a complex relationship between the patient, outpatient ophthalmologist and glaucoma surgeon.

The incidence of combined cataract and glaucoma ranges from 14.6% to 76%, and increases to 85% in the case of pseudoexfoliation syndrome. Analysis of the literature revealed the influence of factors associated with glaucoma on the process of cataract development. Previously performed laser surgery or glaucoma surgery leads to cataract progression in glaucoma patients in 23.3% and 81% of cases, respectively. To solve this problem, some researchers suggest performing combined one-stage lens removal surgery with a hypotensive component, which reduces intraocular pressure and improves visual function. Up to 13.7% of cases associated with complications of glaucoma surgery lead to cataract progression. Cataract surgery in patients with glaucoma in most cases is performed at the moderate (44.6–59.8%) and advanced (18.7–30.3%) stages, which does not eliminate the theory of the influence of optic neuropathy progression on the process of cataract development. The incidence of cataract and pseudoexfoliation glaucoma comorbidity can reach 40.5–90%. Pseudoexfoliation syndrome leads to cataract progression with disruption of the suspensory apparatus of the lens due to the deposition of exfoliative material in the anterior segment of the eye. Presence of lens subluxation causes difficulties at the time of cataract extraction and increases the risk of intraoperative complications.

Glaucoma is the leading cause of irreversible blindness worldwide. Despite the large variety of treatment methods used in glaucoma, most researchers believe that surgery is the most effective way to normalize the level of intraocular pressure and preserve visual functions. Trabeculectomy and glaucoma drainage implantation are the most commonly performed glaucoma surgeries. Although trabeculectomy is the gold standard, at present time there is an uptrend in the use of glaucoma drainage devices. Ahmed glaucoma valve (AGV) is one of the most widely used glaucoma drainage devices in the world. This review of literature presents contemporary results of AGV implantation, possible complications and ways of optimizing that technique.