The aim of the present study was to investigate the relationship between intraocular pressure (IOP), vessel density (VD), retinal nerve fiber layer (RNFL) parameters and overall defect (OD) of the visual field in eyes where antiglaucoma treatment had not yet been initiated. A total of 61 subjects (122 eyes) who had an IOP of >20 mmHg on several occasions, in at least one eye, in routine outpatient care were included. These were subjects who had never been treated for hypertension glaucoma. The cohort was divided into four subgroups. In the first group, there were 18 eyes with an IOP value of <20 mmHg. In the second group, there were 39 eyes with IOP values of 20-22 mmHg. The third group consisted of 32 eyes with IOP values of 22-24 mmHg and the final group consisted of 33 eyes with IOP values of >24 mmHg. The IOP results were compared with VD, RNFL and OD using Pearson's correlation coefficient to assess the relationship between the selected parameters. RNFL and OD were moderately correlated only in the group of eyes with an IOP value >24 (r=0.48); in the other groups the correlation was very weak. However, changes in visual field were already observed in eyes with IOP 20-22 mmHg (r=-0.27). There was a moderate correlation in eyes with an IOP value >24 mmHg (r=-0.53). The most significant result observed was the relationship between VD and RNFL. In eyes with an IOP value ≤20, a moderate to strong correlation between these parameters was observed. This relationship increased with increasing IOP values up to a very strong correlation in the group with an IOP value >24 mmHg. A moderate to strong dependence between VD and RNFL in eyes with an IOP value ≤20 mmHg was observed, and this dependence was very strongly correlated in the eyes with an IOP value >24 mmHg.
The study provides an up-to-date overview of pathogenesis, functional and structural changes in normal tension glaucoma (NTG) and its differences from high tension glaucomas (HTG). The authors point to less known facts which make both diagnostic groups different. First of all, there are electrophysiological findings that verify pathology in the complete visual pathway in HTG in contrast to NTG where the retinal ganglion cell response is relatively normal but the abnormalities are in the visual pathway. This corresponds to the findings of functional magnetic resonance imaging of the brain with a significant decrease in activity in HTG compared to NTG. We found a higher decrease in activity in HTG following application of the colour paradigm compared to NTG where we did not see a similar difference. We also investigated the central corneal thickness (CCT) in both diagnostic groups. We did not find a statistically significant difference. However, we found the effect of CCT on progression of the changes in visual fields in HTG. In relation to suspicion of abnormally low cerebrospinal pressure and a possible cerebrovascular fluid flow disturbance in NTG, we examined the optic nerve thickness (OND) and optic nerve sheath diameter (OSD) at a distance of 4, 8, 16 and 20mm from the posterior pole of the eye. In the comparison with the healthy population, we did not find any abnormalities except for the width of the optic chiasma that was markedly lower in NTG. In relation to a possible impairment of cerebral perfusion we determined the degrees of cerebral atrophy using magnetic resonance imaging by measuring the bicaudate ratio (BCR) and white matter lesions using the Fazekas scale. We did not find a difference between HTG and NTG in BCR. We found statistically significant changes in BCR which correlated with the changes in visual fields. The higher values of the pattern defect were associated with increased brain atrophy (BCR). We did not detect similar relations in the Fazekas scale. We found a significant difference in this parameter among NTG, HTG and a control group. We found the most advanced changes in the patients with HTG. Conclusion: In HTG, impairment of retinal ganglion cells and subsequently also their axons, including visual cortex occurs because of a high intraocular pressure. In NTG, the retinal ganglion cells are relatively normal like the visual cortex, but alteration occurs in their axons. The cause is not a high intraocular pressure but most probably ischemia.
The objective of this study was a retrospective assessment of two-year experience with micropulse cyclophotocoagulation (MP CPC) in the therapy of various types of glaucoma. Material and method: The cohort of patients consisted of 47 people, out of which 16 men and 31 women. An average age of males was 58.9 years (the range from 35 to 78 years), and an average age of females was 64.7 years (the range from 33 to 86 years). Both eyes were treated in three patients, and therefore the total number of assessed eyes was 50. Patients who underwent the therapy were in different stages of glaucoma disease, with various types of primary and secondary glaucoma. Most of the patients were those with primary open angle glaucoma (POAG): 26 patients, followed by patients with secondary pseudoexfoliative glaucoma (PEXG): 9 patients; diagnoses of the remaining patients: 4 patients – secondary pigmentary glaucoma (PG), 3 patients - primary angle closure glaucoma (PACG), 2 patients normal tension glaucoma (NTG), 3 patients - Posner-Schlossman syndrome, 1 patient - Cogan-Reese syndrome, 1 patient - neovascular glaucoma and 1 patient – secondary traumatic glaucoma. On the operated eye prior to the surgery 3 patients underwent laser iridotomy, 4 patients trabeculectomy, 4 patients EX-PRESS® implant, 3 patients EX-PRESS® implant and trabeculectomy and 1 patient transscleral cyclophotocoagulation. During surgery we opted for from 2,000 to 2,250 mW infrared laser with 810 nm wavelength which uses a micropulse system of laser energy emission. For the procedure we used a new MP3 application probe. 30% drop in intraocular pressure (IOP) compared to the baseline IOP values was set as a success. Results: Our results correlated with the most of available studies when we achieved drop in the values of intraocular pressure by the minimum of 30% in 53.4% of the eyes. The effect of therapy failed in 9 eyes (18%) where we subsequently selected a different therapeutic procedure. Conclusion: MP CPC is a non-incisional laser treatment with minimum complications. It is characterized by a high safety profile and predictability of results. In our study we achieved drop in the values of intraocular pressure by the minimum of 30% in 53.4% of treated eyes. Its use is not limited by the type of glaucoma disease. In the event of insufficient effect, it may be repeated.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.