Diurnal Curve of the Ocular Perfusion Pressure.

PURPOSE: To describe the diurnal variation of the ocular perfusion pressure (OPP) in normal, suspects and glaucoma patients. MATERIALS AND METHODS: Seventy-nine subjects were enrolled in a prospective study. The diurnal curve of intraocular pressure (IOP) was performed and blood pressure measurements were obtained. Each participant was grouped into one of the following based upon the clinical evaluation of the optic disk, IOP and standard achromatic perimetry (SAP): 18 eyes were classified as normal (normal SAP, normal optic disk evaluation and IOP < 21 mm Hg in two different measurements), 30 eyes as glaucoma suspect (GS) (normal SAP and mean deviation (MD), C/D ration > 0.5 or asymmetry > 0.2 and/or ocular hypertension), 31 eyes as early glaucoma (MD < -6 dB, glaucomatous optic neuropathy and SAP and MDs on SAP. Standard achromatic perimetry was performed with the Octopus 3.1.1 Dynamic 24-2 program. Intraocular pressure and blood pressure measurements were taken at 6 am, 9 am, 12, 3 and 6 pm. The patients stayed in the seated position for 5 minutes prior to blood pressure measurements. RESULTS: The mean IOP values in all groups did not follow any regular pattern. The peak IOP was found to be greater in suspect [18.70 ± 3.31 (mm Hg ± SD)] and glaucoma (18.77 ± 4.30 mm Hg) patients as compared to normal subjects (16.11 ± 2.27 mm Hg). In studying the diurnal variation of the OPP, we found lower values at 3 pm in normals (34.21 ± 2.07 mm Hg), at 9 am in suspects (54.35 ± 3.32 mm Hg) and at 12 pm in glaucoma patients (34.84 ± 1.44 mm Hg). CONCLUSION: Each group has a specific OPP variation during the day with the most homogeneous group being the suspect one. It is important to keep studying the IOP and OPP variation for increased comprehension of the pathophysiology of glaucomatous optic neuropathy. How to cite this article: Kanadani FN, Moreira TCA, Bezerra BSP, Vianello MP, Corradi J, Dorairaj SK, Prata TS. Diurnal Curve of the Ocular Perfusion Pressure. J Curr Glaucoma Pract 2016;10(1):4-6.

Factors associated with topographic changes of the optic nerve head induced by acute intraocular pressure reduction in glaucoma patients.

PURPOSE: To investigate factors associated with changes in optic nerve head (ONH) topography after acute intraocular pressure (IOP) reduction in patients with primary open-angle glaucoma (POAG). METHODS: Untreated POAG patients (IOP >21 mm Hg) were prospectively enrolled. Systemic and ocular information were collected, including central corneal thickness (CCT) and corneal hysteresis (CH). All patients underwent confocal scanning laser ophthalmoscopy and tonometry (Goldmann) before and 1 h after pharmacological IOP reduction. The mean of three measurements was considered for analysis. Changes in each ONH topographic parameter were assessed (one eye was randomly selected), and those that changed significantly were correlated with patient's systemic and ocular characteristics. RESULTS: A total of 42 patients were included (mean age, 66.7 ± 11.8 years). After a mean IOP reduction of 47.3 ± 11.9%, significant changes were observed in cup area and volume, and in rim area and volume (P < 0.01), but not in mean cup depth (P = 0.80). Multiple regression analysis (controlling for baseline IOP and magnitude of IOP reduction) showed that CH (r(2) = 0.17, P < 0.01) and diabetes diagnosis (r(2) ≥ 0.21, P < 0.01) were negatively correlated with the magnitude of changes in ONH parameters, whereas the cup-to-disc ratio was positively correlated (r(2) = 0.30, P < 0.01). Age, race, disc area, and CCT were not significant (P ≥ 0.12). Including all significant factors in a multivariable model, only the presence of diabetes remained significantly associated with all ONH parameters evaluated (P < 0.01). CONCLUSIONS: Different systemic and ocular factors, such as diabetes, CH, and the relative size of the cup, seem to be associated with the magnitude of changes in ONH topography after acute IOP reduction in POAG patients. These associations partially explain the ONH changes observed in these patients and suggest that other factors are possibly implicated in an individual susceptibility to IOP.

A comparison between microperimetry and standard achromatic perimetry of the central visual field in eyes with glaucomatous paracentral visual-field defects.

BACKGROUND AND AIMS: The aim was to correlate retinal sensitivity as determined by scanning laser ophthalmoscope microperimetry (SLO-MP) in glaucomatous eyes with paracentral visual field (VF) defects detected by standard automated perimetry (SAP). METHODS: Twenty eyes with glaucomatous optic neuropathy and an SAP VF defect involving the central 16 test points (at least one point with p<1% in the 24-2 VF) were enrolled. Eyes with diseases other than glaucoma were excluded. All patients underwent SLO-MP and SAP of the central 10 degrees . Results from each eye were divided into four quadrants for analysis. Normal and abnormal quadrants by SAP were compared with the corresponding normal and abnormal quadrants by SLO-MP. Regression analysis was used to correlate the mean threshold values (dB) of SLO-MP and SAP in each quadrant. Macular optical coherence tomography (OCT) was performed when there was a disagreement between functional tests. RESULTS: The mean age and VF mean deviation were 60.8 (13.4) years and -7.3 (6.1) dB, respectively. There was a significant correlation between SLO-MP and SAP results in all quadrants (r(2)> or =0.68, p<0.001). All abnormal SAP quadrants had a corresponding abnormal SLO-MP quadrant. However, 21% of the normal SAP quadrants had an abnormal corresponding microperimetry result; a corresponding significant reduction in total macular thickness measured by OCT was present in 75% of these quadrants. CONCLUSIONS: Macular sensitivity evaluated by SLO-MP correlates significantly with SAP paracentral VF defects. SLO-MP detected retinal sensitivity reduction in areas of OCT structural damage with normal SAP and suggests that subtle paracentral functional deficits may be present in many more eyes with established glaucoma than generally assumed.

Retinal vascular occlusions occur more frequently in the more affected eye in exfoliation syndrome.

PURPOSE: To evaluate the relationship between retinal vascular occlusions (RVOs) and exfoliation syndrome (XFS) in a cohort of patients with the two conditions. METHODS: We reviewed the records of patients with XFS with or without glaucoma and any type of RVO between 1983 and 2007. Patients with prior incisional surgery or a history of uveitis were excluded. Data collected included demographics, systemic comorbidities, type of RVO, and intraocular pressure (IOP) before the RVO. Slit-lamp biomicroscopy regarding the presence of exfoliation material on the lens capsule and pupillary margin before the vascular event was used to evaluate the laterality and degree of XFS. RESULTS: We identified 36 patients (mean age 78.4+/-8.3 years, 19 women). Most patients were of European descent (34/36) and 20 (56%) had no prior glaucoma diagnosis. The most common retinal vascular events were central retinal vein occlusion (18/36) and BRVO (10/36). Mean IOP between eyes with (19.5+/-6.5 mm Hg) and without (17.9+/-4.8 mm Hg) RVO was similar (P=0.12). RVOs occurred more commonly in the eye with more pronounced XFS in 92% (33/36) of the cases. A similar agreement was found when considering patients with and without glaucoma separately (94% (15/16) vs90% (18/20); P=0.83). In addition, no difference in the agreement percentage was observed when comparing patients with unilateral XFS (87% (13/15)) with all study patients (P=0.87). CONCLUSIONS: Retinal vascular occlusion in patients with XFS occurs most often in the affected or more severely affected eye. As vascular occlusions happened in patients with and without glaucoma in similar proportions, the presence of XFS seems to play an important role in these findings.

Changes in visual function after intraocular pressure reduction using antiglaucoma medications.

PURPOSE: To evaluate the change in visual function after starting glaucoma treatment and correlate this to a decrease in intraocular pressure (IOP) in primary open-angle glaucoma patients. METHODS: A prospective, randomized clinical trial was carried out involving 54 glaucoma patients (54 eyes). After inclusion, patients randomly received timolol maleate 0.5%, brimonidine tartrate 0.2%, or travoprost 0.004% in one randomly selected eye. Patients underwent Goldmann applanation tonometry, visual acuity test, standard automated perimetry (SAP), visual quality perception test (visual analogue scale), and contrast sensitivity (CS) test, in a random order before and after the 4-week glaucoma treatment. RESULTS: There were statistically significant changes in IOP (mean change [standard deviation], 7.8 [3.6] mmHg, P<0.001), SAP mean deviation index (0.84 [2.45] dB, P=0.02), visual quality perception (0.56 [1.93], P=0.045), and CS at frequencies of 12 cycles/degree (0.10 [0.37], P=0.03) and 18 cycles/degree (0.18 [0.42], P=0.02) after the 4-week treatment when compared with baseline. No statistically significant differences were found between the treatment groups in visual function changes after treatment (P>0.40). No significant correlations between IOP reduction and changes in visual function were found (P>0.30). CONCLUSIONS: Visual quality perception, visual field mean deviation index, and CS at higher frequencies improve after starting glaucoma therapy. However, no correlation was found between IOP reduction and changes in visual function, and no differences were found in visual function when the three medications studied were compared.