Relationships between 24h observations in intraocular pressure vs blood pressure, heart rate, nitric oxide and age in the medical chronobiology aging project.

OBJECTIVE: To evaluate associations between intraocular pressure (IOP) and blood pressure (BP), heart rate (HR), serum nitric oxide (NO), diurnal variations, diabetes and aging in data collected during 24h studies of men conducted over 34y. MATERIALS AND METHODS: As part of the Medical Chronobiology Aging Project, male Army veterans, ages 22 to 81y, without a history of eye disease, were studied around-the-clock in May 1969 (n = 13), 1979 (n = 11), 1988 (n = 11), 1993 (n = 11), 1998 (n =12) and 2003 (n = 10). Measurements of IOP (R & L eyes, supine position), BP and HR (sitting position), and collection of blood were obtained every 3h (8 readings/24h) from 19:00h to 16:00h the next day. Individual time series were analyzed for circadian characteristics by the least-squares fit of a 24& 12h cosine. After normalizing all data to percent of mean to reduce inter-subject variability in levels, grouped data were analyzed for time-effect by ANOVA and for circadian rhythm by multiple component (24h&12h) cosine fitting. Individual 24h averages were analyzed by simple and multiple regression for relationships between IOP and systemic variables, diabetic status and age. RESULTS: Over the 34y study span, 22 men provided sixty-three 24h profiles for IOP & HR, 61 for BP, and 21 for NO. Using all normalized data, a significant circadian rhythm was found for each variable at p <0.001. Circadian peaks (orthophases) are located in the late morning for IOP-R (10:20h) and IOP-L (10:52h), and in the evening for HR (18:52h), NO (20:00h), SBP (20:40h) and DBP (21:44h). An out-of-phase relationship of about 10h is noted on a group basis between IOP vs BP, HR and NO. The locations of individual circadian peaks for IOP-R were found around the clock, but with a significant predominance between 10:00 and 16:00h (day type), and 04:00-10:00h (morning type). In contrast, BP, HR and NO showed a significant clustering of evening type or night type peaks. The overall mean IOP for the right eye was slightly, but not significantly, higher than the left eye (17.60+/-0.21 vs 17.34+/-0.18 mmHg; p = 0.385), with a strong positive correlation between both eyes (R = 0.952, p <0.0001). IOP showed a significant positive correlation with SBP (R = 0.49, p <0.001), diabetic status (R = 0.47, p <0.001), age (R = 0.32, p = 0.011), and HR (R = 0.28, p = 0.031). A multiple regression using SBP, DBP, HR, age and diabetic status (5 men became diabetic over the 34y study span) as independent variables resulted in SBP being the strongest predictor of IOP (p = 0.0001), followed by DBP (p = 0.0103). After adjustment for BP, independent effects of age (p = 0.187), HR (p = 0.789) and diabetic status (p = 0.153) were eliminated from the prediction equation. CONCLUSIONS: The results of these studies reveal significant circadian variations in IOP, BP, HR and NO, with peak levels, on average, near noon for IOP and in the evening for BP, HR and NO. An increase in SBP was associated with an increase in IOP. While SBP and DBP are significant predictors of IOP levels, single measurements during regular clinic hours may not reveal the full functional relationship between the variables measured in our studies. Therefore, circadian information on total 24h patterns may contribute to the reliability of diagnosis and guide proper individualized timing of optimal patient management (e.g., for glaucoma, hypertension, diabetes, among other conditions).

Spontaneous dural cavernous sinus fistula in a child.

We describe the clinical course of a 9-year-old boy in whom a spontaneous dural cavernous sinus fistula developed. The patient initially presented with proptosis and conjunctival congestion believed to be caused by a cavernous sinus hemangioma and was prescribed oral prednisone. He subsequently developed pain, increased proptosis, and decreased vision. Emergent angiography revealed a dural cavernous sinus fistula, which was successfully embolized. This is the first case to our knowledge of a dural cavernous sinus fistula in a noninfant child that was treated successfully with embolization during angiography.

Neodymium:YAG laser posterior capsulotomies performed by residents at a Veterans Administration Hospital.

PURPOSE: To assess the initial efficacy of neodymium:YAG (Nd:YAG) laser posterior capsulotomies performed by residents at a teaching institution and to evaluate the associated complications over an extended follow-up. SETTING: Department of Ophthalmology, Edward Hines, Jr. Veterans Administration Hospital, Hines, Illinois, USA. METHODS: This retrospective noncomparative case review comprised 212 pseudophakic eyes having Nd:YAG laser posterior capsulotomies from April 1992 through March 1995. Evaluated were postoperative changes in best corrected visual acuity (BCVA), intraocular pressure (IOP) elevations, and complications related to the procedure. RESULTS: In all 212 eyes, Snellen visual acuity was obtained at least 1 week after the capsulotomy. The BCVA in 96 eyes (45.3%) improved by 3 or more lines, in 43 (20.3%) by 2 lines, and in 51 (24.1%) by 1 line. Nineteen eyes (9.0%) did not improve by 1 or more lines, and 3 eyes (1.4%) had decreased Snellen acuity. All but 4 eyes with less than 1 line of improvement had underlying ocular pathology or a previous incomplete capsulotomy. For evaluation of postoperative complications, long-term follow-up was available for 133 of 212 eyes (62.7%). The mean follow-up for this group was 3.18 years. Postoperative complications were found in 14 of these eyes (10.5%). Nine (6.8%) had a rise in IOP greater than 10 mm Hg after the capsulotomy. One eye (0.8%) developed a persistent iritis, 2 (1.5%) had vitreous prolapse into the anterior chamber, and 2 (1.5%) developed rhegmatogenous retinal detachments. CONCLUSION: Postoperative Snellen acuity results and complication rates compare favorably with those in previous studies. The results indicate that Nd:YAG laser posterior capsulotomies performed by residents with attending supervision are safe, effective, and carry a low associated complication rate over a long follow-up.

Retinal and choroidal manifestations of cat-scratch disease.

OBJECTIVE: The ability to diagnose cat-scratch disease (CSD) has been facilitated greatly by the recent isolation and characterization of Bartonella henselae (formerly genus Rochalimaea) and Afipia felis and by the subsequent development of specific enzyme-linked immunosorbent assay (ELISA) serologic tests. This study will help define the patterns of posterior segment ocular involvement in patients with confirmed CSD. DESIGN: The study design is a retrospective case study and literature review. PARTICIPANTS: Two consecutive patients with acute visual loss from retinal manifestations of CSD participated. INTERVENTIONS: The diagnosis was confirmed by B. henselae ELISA testing. Patients underwent extensive medical and ophthalmic investigations to exclude other causes of retinal and choroidal disease. Ophthalmic investigation included fluorescein angiography and visual field testing. One patient received antibiotic therapy with cefotaxime, then with ciprofloxacin, and was treated with oral prednisone. The other patient was improving for several weeks before oral doxycycline was given. MAIN OUTCOME MEASURES: The clinical syndromes observed were studied over time using visual acuity, visual field, and clinical findings. Data were collated with cases from the literature. RESULTS: Unilateral neuroretinitis and an unusual macular retinitis developed in patient 1, as did bilateral small intraretinal white spots and a unilateral choroidal infiltrate that continued to develop while the patient received antibiotic treatment. Patient 2 had a branch arteriolar occlusion in relation to a perivascular retinal infiltrate and a few small, bilateral, intraretinal white spots. There was gradual resolution with visual improvement while the patient received the antibiotic treatment, although therapeutic efficacy could not be determined. Patient 1 also received oral corticosteroids. A detailed analysis of the literature placed these findings in context. CONCLUSIONS: An unusual, well-defined retinal opacification with features of both multiple retinal arteriolar occlusions and a low-grade retinitis was described. Several features also may occur in posterior segment CSD, including neuroretinitis, a retinal white spot syndrome, and focal choroiditis.

Atrial natriuretic peptide gene expression in the rat gastrointestinal tract.

The presence of ANP prohormone immunoreactivity in rat GI tract suggests that it may be an extracardiac site of ANP synthesis. The aim of this study was to investigate the expression of ANP mRNA in the adult rat GI tract. ANP mRNA was detected by ribonuclease protection analysis in stomach, small and large intestines, and rectum/anus. The highest concentrations of ANP transcripts were found in the proximal stomach, antrum, proximal colon, and rectum/anus at levels that ranged from 1 to 10% of that found in cardiac ventricle. Northern blot analysis of total RNA from these tissues identified a single 0.9 kb ANP transcript similar to that detected in heart. Gel filtration chromatography of tissue extracts provided evidence for the presence of the complete ANP prohormone in proximal stomach, antrum, proximal colon and rectum/anus. These results demonstrate that the gene for ANP is expressed in specific regions of the rat GI tract, suggesting that tissue-specific differential regulation of ANP synthesis occurs within the GI tract.

Molecular forms of circulating atrial natriuretic peptides in human plasma and their metabolites.

High performance gel permeation chromatography (HP-GPC) followed by four radioimmunoassays (RIAs) devised to amino acids (a.a.) 1-30, 31-67, 79-98, and 99-126 of the 126 a.a. atrial natriuretic factor (ANF) prohormone revealed that the proANF(1-30) assay immunoreactivity in plasma is 50% proANF(1-30) and 50% proANF(1-98). The HP-GPC evaluation of plasma followed by proANF(31-67) and ANF [i.e., proANF(99-126)] assays revealed that proANF(31-67) and ANF circulate as distinct peptides. the HP-GPC plasma examination followed by proANF(79-98) assay immunologically recognized three peaks in plasma consistent with proANF(1-98), -(68-98), and -(79-98). Similar HP-GPC evaluation of urine followed by these RIAs indicated that the proANF(1-30), -(79-98), and ANF assays only recognize 500 mol.wt. or less peptides, and the proANF(31-67) RIA recognizes a nearly intact proANF(31-67) with only two to three amino acids removed during processing of this peptide.