Patterns of early visual field loss in open-angle glaucoma.
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Aged↗
Biomedical subjects
J Caprioli
Publications and source records attributed to J Caprioli.
Comparison of the optic nerve head in high- and low-tension glaucoma.
The optic nerves of 34 eyes of 34 patients with low-tension glaucoma were compared with those of 41 eyes of 41 patients with high-tension glaucoma. Mean intraocular pressure in the low-tension group was 16.9 +/- 0.7 mm Hg (mean +/- SEM) compared with 31.7 +/- 0.8 mm Hg in the high-tension group. Mean total visual field loss was not significantly different in the two groups, as determined by computerized threshold perimetry (OCTOPUS). The optic disc rim in low-tension eyes was significantly thinner than in high-tension eyes (P = .018); the largest difference occurred inferiorly and inferotemporally (P less than .001). The appearance of the optic nerve is useful to distinguish between these two subtypes of glaucoma and may be a more meaningful indicator than intraocular pressure. Our findings support the hypothesis that there are at least two different mechanisms for optic nerve damage in glaucoma.
Adult↗
Static threshold examination of the peripheral nasal visual field in glaucoma.
Quantitative computerized threshold perimetry (OCTOPUS) was used to study the peripheral nasal field in patients with glaucoma and patients suspected to have glaucoma. Peripheral nasal defects (detected with a specially designed program) were found in the absence of abnormalities in the central field (as measured by OCTOPUS Program 31 or 32) in approximately 11% of all eyes being evaluated for glaucoma. Examination of the peripheral nasal field by sensitive quantitative threshold perimetry should be included in the careful evaluation of patients with glaucoma and those suspected to have glaucoma. This procedure not only will allow identification of early defects but also will allow careful follow-up of quantified abnormalities over time.
Aged↗
Cyclocryotherapy in the treatment of advanced glaucoma.
Cyclocryotherapy in the treatment of aphakic open-angle glaucoma (AO), aphakic angle-closure glaucoma (ACL), and neovascular glaucoma (NVG) was evaluated in 96 eyes of 96 patients. All patients had follow-up of greater than 12 months, with a mean of 29.0 +/- 2.1 months (+/- SEM). Intraocular pressure (IOP) was lowered to less than 21 mmHg in 76% of eyes with AO, 68% of eyes with ACL, and 55% of eyes with NVG. Patients with NVG lost vision more frequently (70%) than patients with AO (41%) or ACL (41%). Patients with NVG had a higher incidence of loss of light perception and phthisis bulbi than patients with ACL (P less than 0.015). In patients having visual field examinations (76/96), glaucomatous field loss was arrested in 71% of patients with AO and 65% of patients with ACL, compared to 29% of patients with NVG (P less than 0.025). There was a significant correlation between postoperative IOP less than 21 mmHg and preservation of visual field. Patients receiving initial 360 degrees cryosurgical treatment required fewer repeat treatments than patients receiving initial 180 degrees treatment (P = 0.004); complications were slightly more common in the 360 degrees group.
Aged↗
Ocular effect of neodymium-YAG laser.
We aimed a high-powered pulsed neodymium-YAG laser incrementally from air to the anterior portion of the vitreous in rabbits to evaluate its effect on the corneal endothelium, the lens, and the dynamics of intraocular fluid. Corneal endothelium damage occurred as much as 3.5 mm away from the site of optical breakdown. The degree of tissue damage was inversely proportional to the distance from the site of optical breakdown, and the damage pattern at a given distance was the same whether the optical breakdown was anterior or posterior to the corneal endothelium. A single 4-mJ shot (mode-locked train) of laser light causes disintegration and liquefaction of the lens in a spherical area 300 micron in diameter. The damage extends posteriorly to a distance of 450 micron. The effect of this explosion denatures the surrounding cortical fibers for an area of 50 to 80 micron. Increased intraocular pressure was noted in all instances of anterior or posterior capsulotomy, probably as a result of the release of liquefied cortical material and mechanical obstruction of the chamber angle. No increase in intraocular pressure occurred when the lens capsule remained intact.
Animals↗
Comparison of visual field defects in the low-tension glaucomas with those in the high-tension glaucomas.
We compared the visual fields of 79 eyes (48 patients) with low-tension glaucoma (intraocular pressure less than 21 mm Hg) to the visual fields of 106 eyes (74 patients) with high-tension glaucoma (intraocular pressure greater than 30 mm Hg). Both groups had similar amounts of total field loss as determined by computerized threshold perimetry. Scotomas in the low-tension group had a steeper slope (P less than .001), were significantly closer to fixation (P less than .001), and had greater depth (P less than .001) than those in the high-tension group. These findings suggested that more than one causative factor is important in the production of optic nerve damage in glaucoma.
Adult↗
Ocular blood flow in phakic and aphakic monkey eyes.
Alterations in regional ocular blood flow produced by topical epinephrine were studied in phakic and aphakic eyes of Macaca arctoides using the radioactive microsphere technique. Three isotopes were used to make sequential blood flow measurements just prior to topical epinephrine administration, 1 hr later and 3 hr later. Significant reductions of flow were found in the iris, ciliary body, and optic nerve head of both phakic and aphakic groups. Choroidal and posterior optic nerve flow decreased significantly in aphakic eyes only. Decreases in flow were flow decreased significantly in aphakic eyes only. Decreases in flow were maximal at 3 hr. Significant changes in retinal flow were not detected. The implications of these findings regarding epinephrine-induced aphakic cystoid macular edema and the suitability of epinephrine or its derivatives in the treatment of glaucoma are discussed.
Animals↗
Combined effect of forskolin and acetazolamide on intraocular pressure and aqueous flow in rabbit eyes.
Forskolin, a diterpene, a potent and direct stimulator of the catalytic unit of adenylate cyclase, can reduce intraocular pressure when administered topically to rabbit eyes in a 1% suspension. Using an intravitreal plant of fluorescein-dextran, aqueous flow was measured by a modification of the method of Maurice. Forskolin reduces net aqueous flow by 51% compared to the controls. Acetazolamide (25 mg kg-1) administered intravenously reduces net aqueous flow by 45%. Forskolin and acetazolamide together reduce net aqueous flow by 72%, an important additive effect undoubtedly produced by different pathways.
Acetazolamide↗
The histopathology of black ball hyphema: a report of two cases.
Two black ball clots manually expressed through limbal incisions four and seven days after total traumatic hyphema were examined histologically. The surface of both clots consists of a fibrin "pseudocapsule" with no attachments to intraocular structures. There is a cohesive internal structure formed by concentric fibrin layers. No fibroblastic or neovascular activity was present. Intracameral clots evolve differently than intravascular clots. True organization of the black ball hyphema clot does not appear to take place within the first seven days after black ball hyphema secondary to contusion trauma.
Adolescent↗
Forskolin lowers intraocular pressure by reducing aqueous inflow.
Forskolin is a diterpene derivative of the plant Coleus forskohlii that stimulates adenylate cyclase activity without interacting with cell surface receptors. Forskolin lowers the intraocular pressure of rabbits, monkeys, and humans. In rabbits, net aqueous humor inflow decreases, outflow facility remains unchanged, and ciliary blood flow increases. Tolerance to the intraocular pressure lowering effect did not occur in rabbits after topical doses given every 6 hr for 15 days. In vitro forskolin activates adenylate cyclase of crude particulate homogenates prepared from cultured human ciliary epithelia or from dissected ciliary epithelial processes of rabbit or human eyes. This activation is not blocked by timolol. The stimulation of adenylate cyclase by isoproterenol in vitro is potentiated in the presence of forskolin. Forskolin represents a potentially useful class of antiglaucoma agents differing in molecular mechanism of action from previously used drugs.
Adenylyl Cyclases↗
Forskolin lowers intraocular pressure in rabbits, monkeys, and man.
Topical ocular application of forskolin, a diterpene that increases intracellular cyclic adenosine monophosphate by stimulating adenylate cyclase directly without cell surface mediation, lowered intraocular pressure (IOP) in rabbits, monkeys, and volunteers who were free from eye disease. In man 50 microliters of a topical suspension of 1% forskolin significantly lowered IOP in 1 h, the effect reaching a peak at 2 h but remaining significant for at least 5 h. Outflow pressure fell by 70% on average. Forskolin and its analogues represent a new class of drugs active against glaucoma which differ in their molecular actions from any previously used drug.
Adenylyl Cyclases↗
Caution on the preoperative use of topical timolol.
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Administration, Topical↗
Basal encephalocele and morning glory syndrome.
Basal encephaloceles are often associated with other midline anomalies such as hypertelorism, broad nasal root, cleft lip, and cleft palate. Optic disc anomalies such as pallor, dysplasia, optic pit, coLoboma, and megalopapilla have been reported to occur in patients with basal encephalocele We report a case of a child with a sphenoethmoidal encephalocele and morning glory syndrome of the optic nerve. The presence of such optic nerve anomalies with facial midline anomalies should alert the clinician to the possible presence of a basal encephalocele.
Encephalocele↗
Acute monocular visual loss secondary to anterior communicating artery aneurysm in a patient with sickle cell disease.
A patient with sickle cell disease had acute monocular visual loss with no visible vitreal or retinal abnormalities. A large aneurysm of the anterior communicating cerebral artery was found, with direct compression of the optic nerve. This represents a very rare presentation of a relatively common lesion. Consideration should always be given to compressive lesions as the cause of acute monocular visual loss in the absence of visible vitreal, retinal, or optic nerve disease.
Acute Disease↗
Proline metabolism in sepsis, cirrhosis and general surgery. The peripheral energy deficit.
Proline metabolism was prospectively evaluated in patients with surgical sepsis, cirrhosis, and elective surgical procedures. Significant correlations were found in the septic patients. Proline levels were an excellent indicator of mortality and correlated positively with lactate levels. Lactate and proline were inversely related to total peripheral resistance and oxygen consumption. In septic patients who expired: the metabolites involved in the hepatic pathways of proline degradation were elevated in proportion to proline; lactate, glutamate and proline were directly related to pyruvate; lactate/pyruvate ratios were constant; proline, glutamate, ammonia, ornithine, lactate and pyruvate levels were inversely proportional to oxygen consumption and total peripheral resistance. The primary defects in sepsis seem to be metabolic; there are very strong correlations in time between physiology and metabolism; the metabolic abnormality seems to be a progressive energy-fuel deficit, possibly from a progressive inhibition of substrate entry into the Krebs cycle.
Citric Acid Cycle↗
The adenylate cyclase receptor complex and aqueous humor formation.
The secretory tissue of the eye, the ciliary processes, contains an enzyme receptor complex, composed of membrane proteins, the catalytic moiety of the enzyme adenylate cyclase, a guanyl nucleotide regulatory protein (or N protein), and other features. The enzyme can be activated by well-known neurohumoral or humoral agents, catecholamines, glycoprotein hormones produced by the hypothalamic pituitary axis, and other related compounds, including placental gonadotropin, organic fluorides, and forskolin, a diterpene. These compounds cause the ciliary epithelia to produce cyclic AMP at an accelerated rate. Cyclic AMP, as a second messenger, causes, either directly or indirectly, a decrease in the net rate of aqueous humor inflow that may be modulated by cofactors. Clinical syndromes fit the experimental data so that an integrated explanation can be given for the reduced intraocular pressure witnessed under certain central nervous system and adrenergic influences. The molecular biology of this concept provides important leads for future investigations that bear directly both upon the regulation of intraocular pressure and upon glaucoma.
Adenylyl Cyclases↗
Temporal corneal phacoemulsification combined with separate-incision superior trabeculectomy.
We describe our present method of combined cataract surgery and trabeculectomy, which involves temporal clear corneal phacoemulsification with foldable intraocular lens implant combined with a separate-incision superior limbus-based trabeculectomy. The potential advantages over combined surgery through a single incision include reduced manipulation of conjunctival and scleral flaps, improved visibility for phacoemulsification, and a slightly shorter tunnel.
Cataract Extraction↗