Response to topical epinephrine. A practical prognostic test in patients with ocular hypertension

Eighty patients with ocular hypertension (intraocular pressure greater than 20 mm Hg) and GG-response to topical corticosteroids (over 31 mm Hg after six weeks of topical dexamethasome 0.1% four times a day) were tested for ocular hypotensive response to topical epinephrine. Of 80 patients observed for five to ten years, 20 (25%) developed gluacomatous visual field defects, and 34 (43%) were "responders" to topical epinephrine (IOP reduction of greater than 5 mm Hg). Of 20 patients who developed glaucomatous visual field defects, 17 (85%) had responded to topical epinephrine, but only 28% of those who did not have visual field defects showed this type of epinephrine response. Of 34 epinephrine responders, 17 (50%) developed glaucomatous visual field defects as compared to three of 46 (6.5%) nonresponders. The initial applanation IOP level proved less valuable as a prognostic indicator.

Quenching curves: solutions by second-order polynomial regression

This paper describes an inexpensive practical approach for the automated computation of quench corrections in beta-scintillation experiments, using a table-top calculator. This approach applies a second-order fit, ax2 + bx + c = y, where x is the channel A/B ratio for known quench standards and y describes efficiency. There is excellent agreement between measured values and the polynomial expression for most experimental A/B ratios.

Comparison of ocular prostaglandin synthesis inhibitors

A comparative study was carried out of the inhibitory effect of 14 nonsteroidal anti-inflammatory compounds, administered topically, on the intraocular pressure and aqueous humor protein elevation induced by arachidonic acid in rabbits. The most effective agents were flurbiprofen solution and suspensions of indoxole (polysorbate-dispersed), meclofenamic acid, indomethacin, and clonixin.

Plasma cortisol suppression test used to predict the development of primary open-angle glaucoma

Forty patients classified as high responders (GG) to dexamethasone testing (intraocular pressure greater than 31 mm Hg) without visual field loss were subjected to plasma cortisol suppression testing. After a five-year follow-up adequate data were available on 35 patients. Eighteen responded to 1.0 mg of dexamethasone-diphenylhydantoin suppression testing in a similar fashion to patients with primary open-angle glaucoma while 17 responded in a similar fashion to subjects classified as low (NN, intraocular pressure less than 20 mm Hg) and intermediate (NG, intraocular pressure 20 to 31 mm Hg) responders to dexamethasone testing. Eight of the 35 patients developed glaucomatous visual field loss during the follow-up period. These eight patients were not more sensitive to suppression of plasma cortisol than the 27 patients maintaining normal visual fields. Thus, plasma cortisol suppression testing failed to predict the development of primary open-angle glaucoma in GG responders.

Positive FTA-ABS tests in subjects with corticosteroid-induced uveitis

Of 17 subjects who developed severe anterior nongranulomatous uveitis during or immediatelyy after testing with topical corticosteroid preparations, 14 (82%) had a positive fluorescent-treponemal-antibody absorption (FTA-ABS) test. No association was found between corticosteroid-induced uveitis and any specific HL-A locus.

Prognostic factors in glaucomatous visual field loss

A retrospective review was conducted of 31 patients with bilateral elevations of intraocular pressure and unilateral glaucomatous visual field loss. Nine (29%) of the fellow eyes developed visual field loss during a three- to seven-year follow-up period. Of the 13 fellow eyes that had an initial intraocular pressure greater than 26 mm Hg, eight (62%) developed visual field loss, as opposed to one (6%) of the 18 eyes that had lower intraocular pressures. Of the 11 fellow eyes whose intraocular pressures exceeded 24 mm Hg, either treated or untreated, on more than 50% of the measurements, seven (64%) lost visual field, whereas in the 20 eyes whose intraocular pressures were lower, only two )10%) lost visual field.

The effects of dipivalyl epinephrine on the eye

We treated one eye each of ten patients with ocular hypertension with dipivalyl epinephrine (DPE), a congener of epinephrine. Pupil size and intraocular pressure were measured before and at intervals up to 240 minutes after instillation of a single drop of DPE in concentrations from 0.005 to 0.5%. Concentrations of 0.025% DPE and greater significantly reduced IOP, and mydriasis was induced by concentrations of 0.1% DPE or greater. Comcentrations of 0.1% DPE, instilled twice daily for one month, significantly reduced intraocular pressure during diurnal testing on days 2 and 31. No toxic side effects were noted. The DPE produced dose-related increases of cyclic adenosine monophosphate in the aqueous humor of rabbits.

Topical corticosteroid therapy and pituitary-adrenal function

Systemic absorption has been reported after the use of corticosteroid eye drops. Prolonged use could result in adrenocortical insufficiency and an associated adrenal crisis under stressful situations. For that reason, we studied the hypothalamic-pituitary-adrenal axis of patients receiving corticosteroid eye drope. Fifteen patients were given 0.1% dexamethasone sodium phosphate eye drops, one drop (approximately 1/30 ml) to each eye four times a day for six weeks. This dosage resulted in partial adrenal suppression, manifested by reduced levels of plasma cortisol. However, in each case, the hypothalamic-pituitary-adrenal axis, as evaluated with the use of the oral metyrapone tartrate test, was intact.

Differential sensitivity at the cellular level in primary open-angle glaucoma: prednisolone and ouabain

The concentration of drug necessary to inhibit lymphocyte transformation by 50 per cent (I50 value) was determined for the glucocorticoid prednisolone-21-phosphate, and for the sodium-potassium adenosinetriphosphatase inhibitor ouabain, in 37 persons representing the full range of ocular and cellular glucocorticoid sensitivity. The lymphocytes of patients with primary open-angle glaucoma, and of high ocular responders to glucocorticoids, were more sensitive to prednisolone-21-phosphate than were those of ocular low and intermediate responders. By contrast, there was no significant difference in sensitivity to ouabain. There was also no significant correlation of lymphocyte sensitivity to prednisolone-21-phosphate with that to ouabain. These results provide indirect evidence that the increased cellular sensitivity to glucocorticoids in primary open-angle glaucoma is a specific effect, and not merely representative of a general vulnerability of "sick cells."

Relative afferent pupillary defect in glaucoma

Seven patients with asymmetrical open-angle glaucoma had relative afferent pupillary defects. This defect may have occurred during any stage of glaucoma, but the presence of this sign may be indicative of the earliest onset of optic nerve damage in patients with ocular hypertension. Although the presence of an afferent pupillary defect should suggest the consideration of a neurologic lesion, glaucomatous damage may be the sole explanation for this phenomenon.

Visual field progression in open-angle glaucoma patients presenting with monocular field loss

Twenty-one patients with primary open-angle glaucoma were followed an average of 4.4 years after developing monocular field loss. Nine of the undamaged fellow eyes developed field loss, while 16 of the 21 eyes presenting with field loss showed progression of field changes. In 13 patients, the presenting eye had a greater progression of field loss than the fellow eye, and asymmetry of pressure control explained this in only five patients. Eleven patients with symmetric pressure control had progressive field changes in one or both eyes, and in seven, the presenting eye showed greater progression than its fellow. This suggests that an eye with field loss may be more susceptible to progression of field changes at similar pressure levels than an eye without previous damage. Furthermore, patients with unilateral field loss have a greater incidence of field loss in the undamaged fellow eye than do patients with bilateral ocular hypertension.

Increased intraocular pressure after third ventricle injections of prostaglandin E1 and arachidonic acid

Prostaglandin E1 administered into the third ventricle of rabbits produced increased intraocular pressure and body temperature. Similar responses were observed after third ventricle instillation of arachidonic acid, a precursor of prostaglandin E2. Increase of body temperature occurred with lower doses of prostaglandin E1 and arachidonic acid while the intraocular pressure response required larger amounts of these drugs. Pretreatment with aspirin rectal suppositories had no effect on the third ventricle responses induced by prostaglandin E1. Aspirin pretreatment before third ventricle instillation of arachidonic acid blocked the increases of intraocular pressure and temperature.

Home humidifier thermophilic actinomycete isolates

Twenty-seven thermophilic actinomycete isolates obtained from humidification systems or living-bedroom areas of individuals with suspected but unproved home environment-related respiratory disease were characterized morphologically and biochemically. All isolates were demonstrated to be members of the Thermoactinomyces genus. Two previously misidentified isolates were reclassified as a Thermoacetinomyces sp. Thus, all of our thermophilic actinomycete humidifier isolates studied to date have been identified as either Thermoactinomyces vulgaris or Thermoactinomyces sp. Large numbers of unidentified thermotolerant bacteria have also been isolated from virtually all residual humidifier water samples and their possible role in production of "humidifier-associated" respiratory disease is unknown.

Valve implants in filtering surgery

A valve implant for glaucoma incorporated upper and lower intraocular pressure limits for outflow. The device consisted of an open Supramid tube sealed to a Silastic tube with a slit valve. The valve implants had opening pressures of 11 to 16 mm Hg and closing pressures 1 to 3 mm Hg lower. A surgical technique was developed in monkey eyes and applied later in modified form to three patients with glaucoma. In four of seven monkey eyes the implants remained in place and were patent for over one year. Follow-up studies were carried out for over six months in the three patients. In two patients the valve implants were functioning with controlled intraocular pressures. In one patient the implant migrated posteriorly. This was replaced by using a new valve and a buried fixation suture and has since functioned without problem. The valve implants were well tolerated and offered possibilities for predictable intraocular pressures after glaucoma surgery.

The reproducibility of the intraocular pressure response to dexamethasone

The reproducibility of the intraocular pressure response to topical dexamethasone was investigated in 162 persons previously classified as low (NN), intermediate (NG), or high (GG) responders. The concordance of first and second test results was 71% for NN, 74% for NG, and 79% for GG responders, exceeding chance significantly for the NG and GG categories. Quantitative assessment revealed significant correlation of final pressure achieved on first and second tests (r equals .747, P LESS THAN .001). In the course of the study applications of dexamethasone to one eye were noted to have no effect on the intraocular pressure in the contralateral untreated eye, nor did testing of one eye influence the response of the contralateral eye in simultaneous bilateral testing. Using our data to estimate the reproducibility of topical testing in a general population, a value of 73% was obtained. That value was similar to the 65% concordance reported in an identical twin study, suggesting that the limited precision of topical testing accounts for the relatively low concordance found in that study.

Comparison of in vitro corticosteroid response in pigmentary glaucoma and primary open-angle glaucoma

We used an in vitro assay utilizing corticosteroids to inhibit transformation of peripheral blood lymphocytes to evaluate a group of 20 patients with pigmentary glaucoma. The pigmentary glaucoma patient group did not manifest the markedly increased cellular sensitivity to corticosteroids associated with primary open-angle glaucoma. If increased sensitivity to corticosteroids plays an essential role in the pathogenesis of primary open-angle glaucoma, then pigmentary glaucoma appears to be etiologically, as well as clinically, a separate entity.