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This paper presents an analysis of mining area deformations in the rock mass consisting of high depth and strength strata deposited in the cover. The analysis of land surveying results enabled the identification of the parameters required to predict subsidence, which differed from the typical parameters for the Upper Silesian Coal Basin. The parameters of the Budryk–Knothe theory were determined based on the results of geodetic measurements. The calculations of the final state of deformations for planned mining were made using the average and characteristics for the study area parameter values. Based on experience, it is known that the range of subsidence trough depends on the mechanical properties of the rock mass. This study shows that the presence of high-strength rocks also reduces the value of the coefficient of roof control. Subsequently, calculations were made by a computer simulation of longwall mining to determine the course of indices of deformation over time. The calculations were conducted twice: on the assumption that the impact was immediate and on the assumption of the parameter values typical for the basin, and formula expressing the course of subsidence over time with the parameter values based on the measurement results. The obtained distributions of deformation indicators were diametrically opposed to each other. The results of the calculations with the parameter values appropriate for the region indicate that it is possible to carry out a planned mining operation without creating a risk to objects on the surface.

Background: Neovascular glaucoma (NVG) is a severe, potentially blinding disease and a therapeutic challenge. The purpose of this study was to evaluate the safety and efficacy of an integrative surgical approach to neovascular glaucoma. Methods: Retrospective analysis of a one-year follow-up of a consecutive interventional case series of NVG. Eyes underwent transscleral cyclophotocoagulation, pars plana vitrectomy, near-confluent panretinal photocoagulation, and intravitreal bevacizumab. Phakic eyes underwent concomitant cataract surgery. Best-corrected visual acuity (BCVA, logMAR), intraocular pressure (IOP, mmHg), number of glaucoma medication, visual analog pain scale (VAPS, 0-10) were recorded at baseline, and 1, 3, 6, and 12 months. Blind eyes were excluded. Results: Seventy-seven eyes of 77 patients (45 male, 32 female, mean age 73.6±12.2 years) were included. NVG underlying conditions included retinal vein occlusion (41.6%), proliferative diabetic retinopathy (35.1%), central retinal artery occlusion (19.5%), and ocular ischemic syndrome (3.9%). Mean IOP decreased postoperatively from 46.3±10.1 mmHg to 14.5±7.9 mmHg (p

PurposeWe used exact matching for a highly balanced comparison of ab interno trabeculectomy (AIT) with the trabectome to trabeculectomy with mitomycin C (TRAB).Methods5485 patients who underwent AIT were exact-matched to 196 TRAB patients by baseline intraocular pressure (IOP), number of glaucoma medications, and glaucoma type. Nearest-neighbor-matching was applied to age. Success was defined as a final IOP of less than 21 mmHg, IOP reduction of at least 20% reduction from baseline, and no secondary surgical interventions. Outcomes were measured at 1, 3, 6, 12, 18, and 24 months.Results165 AIT could be matched to 165 TRAB. The mean baseline IOP was 22.3±5.6 mmHg, and the baseline number of glaucoma medications was 2.7±1.1 in both groups. At 24 months, IOP was reduced to 15.8±5.2 mmHg in AIT and 12.4±4.7 mmHg in TRAB. IOP was lower than baseline at all visits (p0.01). Secondary surgical interventions had the highest impact on success and became necessary in 15 AIT and 59 TRAB patients. Thirty-two challenging events occurred in TRAB and none in AIT.ConclusionBoth AIT and TRAB reduced IOP and medications. This reduction was more significant in TRAB but at the expense of four times as many secondary interventions.Key messagesDespite vastly different IOP reduction and safety profile, ab interno trabeculectomy with the Trabectome and trabeculectomy with mitomycin C are both used as primary glaucoma surgeries. Exact matching allowed us to strictly focus on identical IOP and medications to create highly similar patient pairs for a balanced comparison that cannot be accomplished short of a randomized controlled trial. We found that trabeculectomy could achieve low IOPs and independence from drops, but trabeculectomies often required postoperative interventions. Trabectome patients had a lesser reduction of IOP and drops but needed far fewer interventions.

Purpose We used exact matching for a highly balanced comparison of ab interno trabeculectomy (AIT) with the trabectome to trabeculectomy with mitomycin C (TRAB). Methods A total of 5485 patients who underwent AIT were exact-matched to 196 TRAB patients by baseline intraocular pressure (IOP), number of glaucoma medications, and glaucoma type. Nearest-neighbor–matching was applied to age. Success was defined as a final IOP of less than 21 mmHg, IOP reduction of at least 20% reduction from baseline, and no secondary surgical interventions. Outcomes were measured at 1, 3, 6, 12, 18, and 24 months. Results A total of 165 AIT could be matched to 165 TRAB. The mean baseline IOP was 22.3 ± 5.6 mmHg, and the baseline number of glaucoma medications was 2.7 ± 1.1 in both groups. At 24 months, IOP was reduced to 15.8 ± 5.2 mmHg in AIT and 12.4 ± 4.7 mmHg in TRAB. IOP was lower than baseline at all visits (p p p p > 0.01). Secondary surgical interventions had the highest impact on success and became necessary in 15 AIT and 59 TRAB patients. Thirty-two challenging events occurred in TRAB and none in AIT. Conclusion Both AIT and TRAB reduced IOP and medications. This reduction was more significant in TRAB but at the expense of four times as many secondary interventions.

Purpose Glaucoma is the world's most common cause of irreversible blindness, which makes early diagnosis, with the goal of preserving vision, essential. The current medical intervention is to reduce intraocular pressure (IOP) to slow down progression of the disease. The main goal of this study was to test a novel handheld acoustic self-tonometer on humans. Methods A sound pressure pulse generated by a loudspeaker causes the eye to vibrate. A pressure chamber is placed on the human orbit to form a coupled system comprised of the patient's eye, the enclosed air, and the loudspeaker. A displacement sensor in front of the loudspeaker membrane allows the dynamic behavior of the entire system to be detected. Results For this clinical trial series, a prototype of the acoustic self-tonometer principle was applied. The resulting membrane oscillation data showed sensitivity of patient IOP, but direct allocation of the measured damping and frequency to the IOP was not significant. For this reason, an artificial neural network was used to find relationships among the subjects’ biometric eye parameters in combination with the self-tonometer data for the IOP reference. An expanded measurement uncertainty (kp = 2) equal to 6.53 mm Hg was determined for the self-tonometer in a Bland–Altman analysis using Goldmann applanation tonometer reference measurements. Conclusions The usability and success rate of producing valid measurement values with the device during self-measurements by test subjects was nearly 92%. The cross-sensitivities observed require compensation in a possible redesign phase to reduce the measurement uncertainty by at least 25% to the maximum of 5 mm Hg required to seek medical device approval. Translational Relevance Building on successful laboratory experiments with pig eyes, this article reports the results of testing the acoustic tonometer on humans.

Background: Porcine eyes have been widely used as ex vivo models in glaucoma research, as they share similar features with human eyes. Freeze-thawing is a non-invasive technique that has been used to obliterate living cells in anterior segment ex vivo cultures, to prepare them for further research such as cellular repopulation. This technique has previously been shown to reduce the intraocular pressure (IOP) in porcine eyes. The aim of this study was to investigate whether freeze-thaw cytoablation causes corresponding canalogram outflow changes in perfused anterior segment cultures (AFT) and whole porcine eyes (WFT). We hypothesized that the known IOP drop in AFT after trabecular meshwork ablation by freeze-thaw would be accompanied by a similarly large change in the distal outflow pattern. Methods: Two-dye (fluorescein and Texas red) reperfusion canalograms were used to compare the outflow time before and after two -80°C cycles of freeze-thaw. We assigned 28 freshly enucleated porcine eyes to four groups: perfused anterior segment dye controls (ACO, n = 6), perfused whole eye dye controls (WCO, n = 6), freeze-thaw treated anterior segment cultures (AFT, n = 10), and freeze-thaw treated whole eyes (WFT, n = 6). Results: In control groups ACO and WCO, the two different dyes had similar filling times. In AFT, the outflow pattern and filling times were unchanged. In WFT, the temporal superior quadrant filled more slowly (p = 0.042) while all others remained unchanged. The qualitative appearance of distal outflow spaces was altered only in some eyes. Conclusions: Freeze-thaw cytoablation caused neither loss nor leakage of distal outflow structures. Surprisingly, the loss of an intact trabecular meshwork over the entire circumference did not result in a general acceleration of quadrant outflow times. The results validate freeze-thawing as a method to generate an extracellular matrix without major structural changes.

PurposeEvaluated the safety and efficacy of an integrative surgical approach to neovascular glaucoma (NVG).MethodsConsecutive interventional case series of NVG with one-year follow-up. Eyes underwent pars plana vitrectomy, near-confluent panretinal photocoagulation, intravitreal bevacizumab, and transscleral cyclophotocoagulation. Phakic eyes underwent concomitant cataract surgery. Best-corrected visual acuity (BCVA, logMAR), intraocular pressure (IOP, mmHg), glaucoma medication score (GMS), visual analog pain scale (VAPS, 0-10) were recorded at baseline, and 1, 3, 6 and 12 months. Blind eyes were excluded.Results83 eyes of 83 patients (53 male, 30 female, mean age 74.6±11.6 years) were included and 53 completed a one-year follow-up. NVG underlying conditions included retinal vein occlusion (n=41), proliferative diabetic retinopathy (n=25), central retinal artery occlusion (n=10), and ocular ischemic syndrome (n=6). Mean IOP decreased postoperatively from 46.0±10.3 mmHg to 14.2±8.9 mmHg (pConclusionsA single, comprehensive surgery session was able to significantly lower IOP, reduce GMS and control pain.

PurposeTo compare 2-year results of a filtering trabeculotomy (FTO) to conventional trabeculectomy (TE) in open-angle glaucoma by exact matching.Methods110 patients received an FTO and 86 a TE. FTO avoided the need for an iridectomy due to a preserved trabeculo-Descemet window anterior to the scleral flap. TE employed a trabecular block excision and iridectomy. Mitomycin C was used in both. FTO and TE were exact-matched by baseline intraocular pressure (IOP) and the number of glaucoma medications. Complete and qualified success (IOP ≤18 mmHg and IOP reduction ≥ 30%, with or without medication) were primary endpoints. IOP, visual acuity (BCVA), complications and intervention were secondary endpoints.Results44 FTO were exact-matched to 44 TE. The IOP baseline in both groups was 22.5±4.7 mmHg on 3±0.9 medications. At 24 months, complete success was reached by 59% in FTO and 66% in TE and qualified success by 59% in FTO and 71% in TE. In FTO, IOP was reduced to 12.4±4.3 mmHg at 12 months and 13.1±4.1 mmHg at 24 months. In TE, IOP was 11.3±2.2 mmHg at 12 months and 12.0±3.5 mmHg at 24 months. Medications could be reduced at 24 months to 0.6±1.3 in FTO and 0.2±0.5 in TE. There were no significant differences between the two groups in IOP, medications, complications or interventions at any point.ConclusionModifying aqueous flow through a limited trabeculotomy in FTO yielded clinical outcomes similar to traditional TE but allowed to avoid an iridectomy.

Background: Neovascular glaucoma (NVG) is a severe, potentially blinding disease and a therapeutic challenge. The purpose of this study was to evaluate the safety and efficacy of an integrative surgical approach to neovascular glaucoma. Methods: Retrospective analysis of a one-year follow-up of a consecutive interventional case series of NVG. Eyes underwent transscleral cyclophotocoagulation, pars plana vitrectomy, near-confluent panretinal photocoagulation, and intravitreal bevacizumab. Phakic eyes underwent concomitant cataract surgery. Best-corrected visual acuity (BCVA, logMAR), intraocular pressure (IOP, mmHg), number of glaucoma medication, visual analog pain scale (VAPS, 0-10) were recorded at baseline, and 1, 3, 6, and 12 months. Blind eyes were excluded. Results: Seventy-seven eyes of 77 patients (45 male, 32 female, mean age 73.6±12.2 years) were included. NVG underlying conditions included retinal vein occlusion (41.6%), proliferative diabetic retinopathy (35.1%), central retinal artery occlusion (19.5%), and ocular ischemic syndrome (3.9%). Mean IOP decreased postoperatively from 46.3±10.1 mmHg to 14.5±7.9 mmHg (p Conclusions: A single, comprehensive surgery session lowered IOP significantly, reduced GMS, and controlled pain.