Vascular parameters and endothelin-1 measurements in glaucoma patients with low- and high-tension optic disc hemorrhages

Abstract

This prospective study aimed to compare vascular parameters (endothelin-1 [ET-1] blood levels, laser Doppler imaging [LDI] of distal phalanxes, and nailfold capillaroscopy) between open-angle glaucoma patients with low- and high-tension optic disc hemorrhages (LTDH and HTDH, respectively). The 33 enrolled patients (mean age, 62.3 ± 13 years) were classified as LTDH or HTDH if they presented at the time of DH detection an intraocular pressure (IOP) < 16 mmHg or ≥ 16 mmHg, respectively. Demographic and ophthalmological data, ET-1 concentrations, LDI (before and 1, 10, and 20 min after cold stimulation), and nailfold capillaroscopy findings were evaluated. The ET-1 blood level was 65% higher in the LTDH (2.27 ± 1.46 pg/ml) than in the HTDH (1.37 ± 0.57 pg/ml; p = 0.03) group. Moreover, there was a statistically significant negative correlation between ET-1 blood concentration and IOP at the time of DH detection (r = −0.45, p = 0.02). Blood flow measurements 10 and 20 min after cold stimulation were lower in the LTDH group than in the HTDH group (p < 0.01). Patients developing DH with lower IOPs have higher ET-1 blood levels and more peripheral vascular dysfunction as estimated by LDI than those with higher IOPs. These findings suggest that distinct underlying mechanisms may be involved in patients developing DH within different IOP ranges.

Is Primary Open-Angle Glaucoma a Vascular Disease? Assessment of the Relationship between Retinal Arteriolar Morphology and Glaucoma Severity Using Adaptive Optics

“…Further investigations of vascular changes in glaucoma would be helpful for better understanding its multifactorial pathogenesis, analysing the causes and effects of vascular and neurodegenerative changes in glaucoma, and the future invention of therapeutic targets, such as endothelin or Caveolin receptors, which can dilate retinal vessels and increase blood flow [2,55]. AO technology, due to its high resolution and image quality, allows the assessment of glaucomatous changes at the cellular level not only in the vessels but also in other structures such as nerve fibres [56][57][58], the lamina cribrosa [59], photoreceptors [60], trabeculae [61], and retinal ganglion cells [62,63].…”

“…Elevated intraocular pressure (IOP) remains the primary risk factor for glaucoma and the only modifiable risk factor that slows disease progression [1]. However, some patients experience disease progression despite significant IOP reductions [2,3]. Since the pathogenesis of glaucoma is multifactorial, other factors, such as reduced axoplasmic flow in retinal ganglion cell (RGC) axons, oxidative stress, and genetic background, may also play important roles [4,5].…”

Is Primary Open-Angle Glaucoma a Vascular Disease? – Assessment of the Relationship of Retinal Arteriolar Morphology and Glaucoma Severity Using Adaptive Optics

“…All these observations suggest that significant vascular alterations are primary in POAG. These investigations may enable the identification of potential targets for future glaucoma treatments, such as endothelin or Caveolin receptors, which can dilate retinal vessels and increase blood flow [2,56]. While numerous studies substantiate the existence of a vascular mechanism leading to neurodegenerative glaucoma damage, it is essential not to forget that glaucoma itself can initiate retinal vascular abnormalities as secondary manifestations of the disease [7,9,57,58].…”

“…Glaucoma is the leading cause of irreversible blindness worldwide, but still, its aetiology is not entirely determined [1]. Although elevated intraocular pressure (IOP) remains the most critical risk factor for glaucoma, only one-third to one-half of patients have elevated IOP at the initial stages [2]. Moreover, many patients may experience disease progression despite typical intraocular pressure values [3].…”

Normal-Tension Glaucoma: Epidemiology, Pathogenesis, Diagnosis and Treatment. Literature Review. Part 2. Role of Vascular Dysregulation in the Pathogenesis. Treatment of Normal Tension Glaucoma

“…Однако эта информация не всегда является достоверной, тем более в отсутствие основного признака ПСД: повышенного уровня ЕТ-1 в крови. Более надежным диагностическим критерием являются показатели проб с локальным охлаждением [17]. Дело в том, что в нормальных условиях глазной кровоток при ПСД может быть не нарушен, однако сбой происходит в условиях провокационных тестов, например холодового.…”