Relationship between the effect of carbon dioxide inhalation or nilvadipine on orbital blood flow in normal-tension glaucoma.

PURPOSE: To investigate the relationship between the effect of carbon dioxide (CO2) inhalation or oral nilvadipine, a calcium-channel blocker, on orbital blood flow in patients with normal-tension glaucoma, as determined by color Doppler imaging. PATIENTS AND METHODS: Sixteen patients with normal-tension glaucoma (mean age, 55.6+/-9.8 years; male:female ratio, 3:13) underwent color Doppler imaging to measure the resistance index, and peak systolic and end-diastolic blood flow velocities of the ophthalmic artery, central retinal artery, and nasal and temporal short posterior ciliary arteries. Measurements were taken before and during CO2 supplementation sufficient to increase the end-tidal CO2 partial pressure by 10%. The color Doppler imaging measurements were repeated after 2 to 4 weeks of treatment with 2 mg oral nilvadipine, and comparisons were made between the effects of the two treatments. RESULTS: Both CO2 inhalation and nilvadipine treatment significantly reduced the resistance index in the central retinal artery, nasal short posterior ciliary artery, and temporal short posterior ciliary artery. There was a significant correlation between the effects of the two treatments on the difference in the resistance indexes of the ophthalmic artery and central retinal artery, but not on those of the nasal or temporal short posterior ciliary artery. CONCLUSIONS: Both CO2 inhalation and oral nilvadipine significantly reduce the resistance index measured by color Doppler imaging in orbital vessels. The effect of oral nilvadipine might be predicted by CO2 inhalation in patients with normal-tension glaucoma.

Changes in optic nerve head blood flow and retrobular hemodynamics following calcium-channel blocker treatment of normal-tension glaucoma.

BACKGROUND: Because calcium channel blockers reduce vascular resistance, they may have a clinical application in the treatment of normal-tension glaucoma (NTG). This study investigates changes in both the optic disc blood flow and the hemodynamics of retrobulbar vessels in NTG patients after the systemic administration of a calcium channel blocker. METHODS: Twelve eyes of 12 NTG patients (mean age 57.6 +/- 15.3 years) were examined before and after a 4-week treatment with 2 mg b.i.d. oral nilvadipine, an L-typc calcium channel blocker. By scanning laser-Doppler flowmetry (SLDF), we obtained the velocity, flow, and volume from within a 10 x 10 pixel window placed on the temporal rim region of the optic disc perfusion map. By ultrasound color Doppler imaging (CDI), we measured the peak systolic velocity (PSV) and the end diastolic velocity (EDV) of the ophthalmic artery (OA), central retinal artery (CRA), nasal posterior ciliary artery (NPCA), and temporal posterior ciliary artery (TPCA). We then calculated a resistance index (RI) for each vessel. RESULTS: After treatment, the flow and velocity of the optic disc blood flow significantly increased (P < 0.05). Nilvadipine also significantly reduced RIs of the CRA, NPCA, and TPCA (P < 0.05), and increased both the PSV of the NPCA and the EDVs of the CRA, NPCA, and TPCA. The percent change in velocity correlated significantly with the percent changes of the CRA RI and NPCA RI. CONCLUSIONS: Oral nilvadipine appears to reduce orbital vascular resistance, which consequently increases the optic disc blood flow.

The effect of nilvadipine, a calcium-channel blocker, on the hemodynamics of retrobulbar vessels in normal-tension glaucoma.

PURPOSE: To investigate the effect of nilvadipine, a calcium-channel blocker, on the hemodynamics of retrobulbar vessels in normal-tension glaucoma. METHODS: Twenty-five patients who prospectively met the enrollment criteria underwent color Doppler imaging of the retrobulbar vessels before and after receiving 4 weeks of treatment with 2 mg oral nilvadipine twice daily. RESULTS: Nilvadipine significantly increased the end-diastolic velocity in the central retinal artery and a short posterior ciliary artery. It significantly reduced the resistance index in the central retinal artery and posterior ciliary arteries, but not in the ophthalmic artery. The calculated ocular perfusion pressure was not affected. CONCLUSION: Oral nilvadipine reduces vascular resistance in distal retrobulbar arteries in normal-tension glaucoma without affecting more proximal blood vessels. Therefore, nilvadipine may have a beneficial effect on the hemodynamics of retrobulbar vessels in normal-tension glaucoma.

Correlation of the peripapillary atrophy area with optic disc cupping and disc hemorrhage.

PURPOSE: To investigate the association of the peripapillary atrophy area with disc cupping area and disc hemorrhage in subjects who underwent ocular examination as part of a routine physical examination. METHODS: We reviewed plain color fundus photographs taken of 12,140 eyes of 6,070 subjects as part of a routine health examination. The refractive error in these eyes was not known. Using a computerized image analysis system, we measured the area of peripapillary atrophy (zone beta), the optic disc, and optic disc cupping by means of planimetry in 8,842 eyes of 4,421 subjects with fundus images of good quality. RESULTS: The ratio of cup area to disc area was significantly greater in eyes with peripapillary atrophy (0.36 + 0.09) than in eyes without peripapillary atrophy (0.34 + 0.07), and the ratio of peripapillary atrophy area to disc area was significantly greater in eyes with disc hemorrhage (0.26 + 0.34) than in those without disc hemorrhage (0.09 + 0.18). Moreover, in eyes with peripapillary atrophy, the ratio of cup area to disc area was significantly larger in eyes with disc hemorrhage (0.48 + 0.08) than in those without disc hemorrhage (0.36 + 0.09). These results remained statistically unchanged even after "glaucomatous" eyes were excluded from the study. CONCLUSION: Peripapillary atrophy appears to be associated with a higher degree of cupping of the optic disc and disc hemorrhage, and the results suggest an association between peripapillary atrophy and glaucomatous optic neuropathy.

Use of antifibrosis agents and glaucoma drainage devices in the American and Japanese Glaucoma Societies.

PURPOSE: To investigate practice patterns among glaucoma subspecialists in the American Glaucoma Society (AGS) and the Japanese Glaucoma Society (JGS), regarding use of antifibrosis agents and glaucoma drainage devices. METHODS: An anonymous survey incorporating 10 clinical situations was mailed to all AGS and JGS members in December 1995. RESULTS: Half of the AGS (105 of 210), and JGS (25 of 50) members returned surveys. Most respondents (51-87%) preferred trabeculectomy with adjunctive mitomycin for all 10 clinical situations. Mitomycin concentrations varied from 0.1 to 0.8 mg/ml (range of means for 10 situations 0.31-0.39 mg/ml) and intraoperative application times ranged from 5 s to 7 min (range of means for 10 situations 2.5-4.6 min). Preferences for either no antifibrosis agent (up to 39%) or 5-fluorouracil (up to 29%) were highest in primary trabeculectomy. Thirty-seven percent to 64% of AGS members used glaucoma drainage devices, especially after complicated postsurgical glaucomas (after penetrating keratoplasty, scleral buckling, or pars plana vitrectomy) and in neovascular glaucoma, but few JGS members used them. Large differences between university- and private practice-based AGS members were found only in mitomycin use for primary trabeculectomy (33% vs. 52%, respectively; p = 0.07) and for complicated postsurgical glaucomas (46% vs. 70%, respectively; p = 0.03). CONCLUSIONS: Trabeculectomy with mitomycin was the preferred surgical procedure among AGS and JGS members in the clinical situations surveyed. Mitomycin concentration and time of application varied widely. Many respondents used 5-fluorouracil or no antimetabolite in primary trabeculectomy. Glaucoma drainage devices were widely used for complicated glaucomas in the United States.

Anterior chamber reaction after mitomycin and 5-fluorouracil trabeculectomy: a comparative study.

We measured aqueous flare in 16 glaucomatous eyes after trabeculectomy in which 5-fluorouracil (5-FU) or mitomycin C (MMC) had been used as an adjunctive therapy. The eyes were divided into a 5-FU and an MMC group, matched for factors that might influence the postoperative inflammatory response to intraocular surgery. Seven eyes of seven patients received subconjunctival injections of 5-FU (50 mg in 2 weeks) and nine eyes of nine patients were given 0.2 mg/0.5 mL MMC intraoperatively. The aqueous flare converted to an albumin concentration (mg/dL) was significantly higher in the 5-FU group than in the MMC group (359.6 +/- 113.8 mg/dL and 143.2 +/- 46.7 mg/dL, respectively; Mann-Whitney U test, P < .05) on the second postoperative day. Intraoperative MMC appears to be no more harmful to the blood-aqueous barrier than 5-FU.

[The effect of the intraocular pressure reduction on glaucomatous disc changes and visual field defects].

The authors prospectively studied changes in the optic disc and visual field associated with intraocular pressure (IOP) reduction for one year after surgery in 12 primary open-angle glaucoma eyes of 7 patients who underwent trabeculectomy because of elevated IOP despite maximum tolerable medical therapy and whose cup volume was demonstrated to be decreased at 3 or 6 months after surgery. Topographic parameters including C/D ratio, rim area and cup volume were determined by the Optic Nerve Head Analyzer plus (Rodenstock). The 30-2 central threshold field was obtained with a Humphrey Field Analyzer at the same time. Mean deviation (MD), corrected pattern standard deviation (CPSD) and total deviation (TD) were used to evaluate visual field changes. Significant improvement of C/D ratio, rim area and cup volume and significant IOP reduction were noted at 1 year after surgery as compared with preoperative baseline value (p less than 0.01). Also the MD was significantly decreased at 1 year after surgery, compared with the preoperative baseline value (p less than 0.05). There was a significant negative correlation between the preoperative MD and the percent change of the MD at 1 year after surgery (r = -0.80, p less than 0.01). Our results suggest that the decrease of optic disc cupping can persist over one year after surgery and that the early visual field defects in glaucoma eyes can gradually improve in association with the decrease of cupping.

Changes in gastric mucosal content of adenosine, xanthine and hypoxanthine induced by restrained water immersion stress: antiulcer effects of tetraprenylacetone.

The purpose of this study was to clarify the involvement of adenine nucleotide metabolism and substrates of the xanthine-xanthine oxidase system as the source of oxygen free radicals in a rat model of restrained water immersion stress ulceration. The gastric mucosal concentrations of adenine-5'-triphosphate (ATP), adenine-5'-diphosphate (ADP), adenine-5'-monophosphate (AMP) and thiobarbituric-acid (TBA)-reactant substances were measured after 4, 8 and 12 h restrained water immersion stress. The gastric mucosal concentrations of the nucleoside adenosine, the purine bases xanthine and hypoxanthine, and the final metabolic product uric acid, were measured after 4 h of restrained water immersion stress. The concentrations of ATP diminished significantly after 4, 8 and 12 h of restrained water immersion stress. However, the observed stress-induced changes in ADP were not significant. AMP concentrations increased significantly after 4, 8 and 12 h of stress. The adenylate pool (ATP + ADP + AMP) dropped significantly from the prestress value after 4, 8 and 12 h of stress, and the concomitant energy charge (EC = ATP + 0.5 ADP/ATP + ADP + AMP) decreased significantly after 4 and 8 h of stress compared with the prestress value. Gastric mucosal concentrations of TBA-reactant substances displayed a significant increase after 4 h of stress, and remained unchanged after 8 and 12 h of stress from the level after 4 h. Four hours of restrained water immersion stress induced an increase in adenosine and uric acid concentrations and a decrease in the hypoxanthine concentration of the gastric mucosa.(ABSTRACT TRUNCATED AT 250 WORDS)

[Measurements of reversibility of optic disc cupping in glaucoma using a computerized videographic image analyzer].

Optic disc changes were studied in young and elderly glaucoma patients who underwent reduction of intraocular pressure (IOP) by filtrating surgery. A computerized videographic image analysis system (Optic Nerve Head Analyzer, Rodenstock) was used to measure the cup/disc-ratio, the ratio of the rim area over the disc area (rim area/disc area-ratio), and the ratio of the cup volume over the disc area (cup volume/disc area-ratio) before and after filtrating surgery. Each parameter was assessed as total and quadrantal values. Materials consisted of 19 eyes of 15 patients (8 eyes of 5 patients with primary open angle glaucoma, 2 eyes of 2 patients with secondary glaucoma, and 9 eyes of 7 patients with developmental glaucoma). Sixteen eyes (84%) of 12 patients showed a decrease of the total cup/disc-ratio after operation. In this group, the patients had a decrease in IOP of 18.9 +/- 10. 6mmHg (mean +/- SD) after the operation. Among 16 eyes that had a decreased total cup/disc-ratio, statistically significant decrease of the cup/disc-ratio (p less than 0.01) and statistically significant increase of the rim area/disc area-ratio (p less than 0.01) were noted in total and for all quadrants except for the temporal. The greatest improvement of cupping was seen in the nasal quadrant. With regard to cup volume/disc area-ratio, a statistically significant decrease was observed in total and in all quadrants (p less than 0.01). The IOP change correlated linearly with that of the total cup volume/disc area-ratio (R = 0.51, p less than 0.05). No statistically significant linear correlation was noted between age and the change in any disc parameter.

[Computerized digital image analysis of optic nerve heads with a three-dimensional image analyzer, IMAGEnet and a comparison with the Optic Nerve Head Analyzer].

Computerized digital image analysis of the optic nerve heads of 17 eyes with various sizes of optic disc cupping was performed using two kinds of three dimensional image analyzers, the IMAGEnet and the Optic Nerve Head Analyzer (ONHA). Intraphotographic error variances of measurements with both instruments were evaluated by measuring each image of the optic discs twice. The mean coefficient of variation (CV) with the IMAGEnet for the vertical cup/disc ratio, the horizontal cup/disc ratio, the cup volume, the rim area, and the rim area/disc area ratio were 3.75%, 3.03%, 7.89%, 2.55% and 1.36%, respectively. With the ONHA, the mean CV for the total cup/disc ratio, the cup volume, the rim area, and the rim area/disc area ratio were 0.82%, 0.21%, 2.39%, and 1.56%, respectively. The value of the cup/disc ratio and the cup volume obtained by the IMAGEnet was smaller than those by the ONHA (p greater than 0.1). Conversely, the rim area and rim area/disc area ratio measured by the IMAGEnet were statistically significantly larger than those by the ONHA (p = 0.01). Statistically significantly positive correlation was demonstrated for measurements made by both instruments in all disc parameters (p less than 0.01). These results seem to indicate the high reliability of the two instruments, however, further investigation is needed for the evaluation of the accuracy of measurements.

The effect of Ca2(+) -antagonist on visual field in low-tension glaucoma.

A prospective study was conducted to evaluate the effects of Ca2(+)-antagonist on the visual field in low-tension glaucoma (LTG). Twenty-five consecutive patients (50 eyes) with LTG received nifedipine at 30 mg/day per os for 6 months. Visual field was tested with an Octopus 201 (program G1) prior to and each month during the period of nifedipine administration. In addition to tonometry and the measurements of systemic blood pressure and pulse rate, the reactivity of peripheral vessels was estimated by determining the response of skin temperature of a finger to cold water (4 degrees C). Twelve eyes (six patients) showed a constant improvement of visual field as expressed by an increase in mean sensitivity (MS). Canonical discriminant analysis demonstrated that the visual field is likely to improve with systemic nifedipine in patients who are young, have a higher initial MS and lower intraocular pressure, and have less decrease in diastolic blood pressure with the nifedipine administration and better cold recovery of skin temperature after their hand is soaked in cold water.