Retinal venous pulsation in glaucoma and glaucoma suspects

PURPOSE: To determine whether changes in central retinal vein pulsation characteristics occur in glaucoma, and how these are related to indices of glaucoma severity. DESIGN: A large, consecutive, prospective, case-controlled study. PARTICIPANTS: Ninety-four consecutive glaucoma patients and 105 glaucoma suspects seen in a tertiary referral clinic were examined. Forty-one age-matched normal subjects also were examined. METHODS: The presence or absence of spontaneous venous pulsation was observed in these 3 groups. The ophthalmodynamometric force (ODF) required to induce venous pulsation at the optic disc was measured in those without spontaneous pulsation. Optic disc photographs were obtained and visual field testing was performed for all subjects. MAIN OUTCOME MEASURES: The prevalence of spontaneous venous pulsation between these 3 groups was compared. The relationship between ODF and visual field mean deviation, neuroretinal rim area, age, intraocular pressure (IOP), gender, and diagnosis of glaucoma was investigated using linear mixed models fitted by Gibb's sampling. RESULTS: Significantly fewer (chi-square, 27.7; P<0.001) glaucoma patients (54%) were observed to have spontaneous venous pulsation than suspects (75%) or normals (98%). A worse visual field mean deviation was shown to be the most significant predictor of a higher ODF (P<0.000), with younger age (P<0.000) also predictive of a higher ODF. A strong relationship between ODF and mean deviation was found in the glaucoma patients (r = 0.59; n = 52; P<0.001). CONCLUSIONS: Spontaneous venous pulsation is less common in glaucoma. The ODF required to induce venous pulsation is increased in glaucoma, and this ODF is greater in those with more severe field loss.     

Modern diagnostic methods for suspected glaucoma and glaucoma

BACKGROUND: Diagnosis of early glaucomatous damage as well as the detection of glaucomatous change are still difficult tasks. During the last years numerous new diagnostic techniques have been investigated and some of them have been introduced to the market. METHODS: This paper reviews the different aims of diagnostic technologies in the field of glaucoma. Methods appearing suitable for a large-scale use by ophthalmologists will be judged according to their suitability to meet the goals of early diagnosis, objective diagnosis, progression analysis and screening. CONCLUSIONS: The new diagnostic techniques have not yet greatly influenced our diagnostic procedure. This is mainly due to the fact that, for the most difficult borderline cases of glaucoma, these methods are of limited value, or have not yet been sufficiently investigated. Nevertheless, the Heidelberg retina tomograph (HRT), the nerve fiber analyzer GDX, short wavelength perimetry (SWAP), and the frequency doubling test (FDT) may play a role in these cases. For follow-up, HRT and GDx have proven valuable, especially in early stages of the disease. The very short testing time of FDT together with good specificity qualifies this test for glaucoma screening.     

Autoimmunity and glaucoma

Elevated intraocular pressure does not explain glaucoma in all patients, but there is information that autoimmune mechanisms may be involved in this disorder. This review attempts to reveal the findings about specific changes in autoantibody profiles in glaucoma patients and their possible role in glaucoma. Considering that these changes in natural autoimmunity can be found consistently among different study populations, it might be a promising new tool for glaucoma detection.     

Iridoschisis and glaucoma

Three patients with unilateral iridoschisis and glaucoma (1 with bilateral open-angle glaucoma, 1 with unilateral glaucoma) were observed for 3 to 15 years. In none of these patients did iridoschisis progress and a good control of the glaucoma was achieved. The mechanism of this rare condition is yet not clear.     

免疫与青光眼

青光眼是不可逆盲的主要原因之一,是视神经的慢性退行性病变.视网膜神经节细胞（RGCs）凋亡和视神经纤维进行性丢失可导致青光眼患者视神经结构和视功能的损害.越来越多的临床和实验研究表明,免疫系统参与青光眼的神经变性过程.青光眼患者视神经变性中涉及免疫机制及免疫系统相关细胞的相互作用,包括眼免疫赦免环境的破坏、胶质细胞的异常激活、T细胞免疫的异常、Th1/Th2免疫失衡、自身抗原的产生、补体通路的激活、氧化应激反应、衰老等免疫因素及氧化应激放大的初始压力损伤,这些因素均可使青光眼视神经进一步损害.就眼的保护性免疫和免疫异常与青光眼的研究进展进行综述.     

Matrix-metalloproteinases and glaucoma

PURPOSE: To analyze the matrix-metalloproteinases' activity (MMP-2 and MMP-9) in primary open angle glaucoma patients with indication for filtrating surgery. METHODS: A prospective study, 8 months, in the Ophthalmology Department of the Central Military Hospital, with the collaboration of "Victor Babes" Institute. The study was conducted on 27 eyes with primary open glaucoma and that have underwent filtrating surgery. Patients with other ocular or systemic associated conditions were excluded. Patients were distributed in 3 groups, according to their topical treatment with prostaglandin analogs: Group A: 11 eyes with travoprost 0,004%. Group B: 9 eyes with latanoprost 0,005%. Group C: 7 eyes without prostaglandin analogs. The fragments collected during surgery were processed for imunohistochimical analysis for MMPs. It has used the indirect tristadial method: streptavidine-biotin-peroxidase.     

Medical therapy of pediatric glaucoma and glaucoma in pregnancy

Although surgery remains the definitive treatment for congenital and other childhood glaucomas, medical therapy can be effective in lowering intraocular pressure as a temporizing measure before surgery or as long-term adjunctive treatment in disease refractory to surgical measures. Carbonic anhydrase inhibitors, beta-blockers, cholinergic drugs, and the prostaglandin-related drugs all play an effective role in pediatric glaucoma management. The usefulness and safety profile of the adrenergic agonists and the osmotic agents are less well established. In medically treating the pediatric patient or the pregnant woman for glaucoma, the clinician must be mindful of the possibility of adverse effects and be prepared to alter or terminate treatment if needed.     

Myopia and glaucoma

2, 528 visual fields of patients with glaucoma were examined. All atypical nerve fibre bundle defects (NFBD) were selected and all myopes. Myopic defects are a) enlargement of the blind spot, occurring in 18% to 30% of the myopic eyes depending in the degree of myopia, b) supertemporal refraction defect (2–6%) and c) irregular defects due to myopic choroidal dystrophy. Atypical NFBD were found in only a few non-myopes but in a large number of myopes. Temporal NFBD occurred in 16% and cecocentral NFBD in 9 to 18% of myopic glaucoma (MG). It is difficult to predict the existence of an atypical defect from optic dise evaluation.     

Pregnancy and glaucoma

Glaucoma, primarily a disease of the older population, may affect women of childbearing age. Pregnancy affects the intraocular pressure (IOP) of women with pre-existing glaucoma. Both elevations and reductions of IOP have been reported during pregnancy. Additionally, visual field test results may fluctuate during pregnancy. In managing the pregnant glaucoma patient with medical therapy, one must consider not only the systemic side effects on the mother, but also any potentially harmful effects on the developing fetus. All anti-glaucoma medications are categorized as class C by the Food and Drug Administration, except brimonidine and nonspecific adrenergic agonists, which belong to class B. In general, the lowest effective dosage of medication should be used. Systemic absorption can be reduced by punctal occlusion, eyelid closure, and blotting the excess drops away during administration. In those patients who need surgery, most local anesthetics may be used safely because they have not been shown to be teratogenic in humans. Antifibrotic agents commonly used adjunctively in trabeculectomy, however, should be avoided. Glaucoma laser procedures, such as laser peripheral iridotomy and laser trabeculoplasty, have been employed without identifiable teratogenic effects or increased risk of side effects for pregnant women.     

Cannabinoids and glaucoma

Glaucoma is one of the leading causes of blindness in the world. In spite of the diverse therapeutic possibilities, new and better treatments for glaucoma are highly desirable. Cannabinoids effectively lower the intraocular pressure (IOP) and have neuroprotective actions. Thus, they could potentially be useful in the treatment of glaucoma. The purpose of this article is to provide the reader with an overview of the latest achievements in research into the potential use of cannabinoids for glaucoma.