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K E Friedl

Publications and source records attributed to K E Friedl.

42 records · Page 3Linked to original sources
PubMed1987

Intraocular lenses in aviators: a review of the U.S. Army experience.

Intraocular lenses are known to be efficacious in the correction of aphakia, but their suitability and durability in Army aviators has not been previously evaluated. Eight experienced pilots (preoperative flight time average: 7,660 hours), who had intraocular lens implants following removal of cataractus lenses, were studied. All had returned to flight duty, seven as pilots, with a total of 2,700 hours postoperative flight time accumulated. All were very pleased with the surgery and with the effectiveness of their lenses. Minor problems included: halos around lights in low illumination (5/8 pilots), erythropsia (2/8), and difficulties with a fixed focal length (2/8). Two aviators reported significant visual problems: complications associated with a platinum loop iris supported intraocular lens, and discomfort and glare stemming from traumatic corneal scarring. A detailed ophthalmological examination revealed abnormalities (5/8 pilots), but none which would be directly attributed to flying. Modern intraocular lenses appear to be an acceptable means of correcting aphakia in Army aviators.

Adult↗
PubMed1987

Conjunctival oxygen tension at high altitude.

Transconjunctival oxygen tension (PcjO2) was studied using a hypobaric chamber and during mountaineering excursions. Measurements obtained during acute chamber exposures (15-20 min) at sea level, 1829 m (6,000 ft), 3048 m (10,000 ft), 4267 m (14,000 ft) and return to sea level were (means +/- SEM): 60.1 +/- 2.7, 49.1 +/- 1.8, 38.3 +/- 2.4, 27.4 +/- 1.5, and 61.1 +/- 2.8 mm Hg, respectively (n = 13). The ratio of PcjO2 to arterial blood oxygen tension (PaO2) did not change in a consistent manner between sea level and 4267 m; PcjO2 was 74 +/- 6.9% of PaO2. The 16 subjects participating in the mountaineering phase of the study revealed similar means at sea level and 1829 m (57.4 +/- 2.4 and 46.3 +/- 1.9 mm Hg respectively), but a smaller decrement was observed at 3048 m (43.0 +/- 1.6 mm Hg). The difference between mountain and chamber values may be accounted for by a partial acclimatization to altitude brought about by longer exposure on the mountain excursions. A comparison between PcjO2 and transcutaneous oxygen tension during the chamber study suggests that a greater precision and sensitivity is obtained with measurement of oxygen tension at the conjunctival site. PcjO2 measurement is a non-invasive reflection of PaO2 which is suitable for continuous monitoring during hypoxia studies.

Adult↗
PubMed1985

Transient reduction in serum HDL-cholesterol following medroxyprogesterone acetate and testosterone cypionate administration to healthy men.

Serum lipids were examined in thirty normal male volunteers who had received depo-medroxyprogesterone acetate (DMPA) and testosterone cypionate (TC) in a male contraceptive trial. Progestagens have been implicated in the changes in serum lipids observed in women using oral contraceptives and this has led to concern about cardiovascular health risks associated with the long-term use of some of these preparations. The following study was done to determine if similar effects occur in men. The men in this study were divided into three DMPA dose groups (50, 100, 200 mg/month) and received intramuscular injections for six months; all men received 250 mg/month TC. There was no significant change in serum high density lipoprotein-cholesterol (HDL-C) levels during the six months of drug administration when compared to levels in the control period. However, there was a marked decrease in HDL-C during the first three months after discontinuation of the drugs (p less than 0.02). This observed change was consistent in each of the three DMPA dose groups but no dose relationship was observed. There was no statistically significant change in serum concentrations of total cholesterol, low density lipoprotein-cholesterol, triglycerides or insulin in any period of the experiment. Serum testosterone (T), estradiol, and sex hormone binding globulin (SHBG), luteinizing hormone (LH), and follicle stimulating hormone (FSH) concentrations were all significantly depressed during the drug administration period. A progestagen dose relationship was observed only for the decrease in serum testosterone and LH concentrations. Serum T and SHBG levels were still significantly reduced at 4-6 months after cessation of the drug administration. These findings demonstrate that DMPA can cause a reduction in serum HDL-C levels. It is suggested that HDL-C concentrations fell only following DMPA withdrawal as a consequence of steroid hormone changes specific to this period.

17-alpha-Hydroxyprogesterone↗
PubMedDate not supplied

Early diagnosis of spinal metastases by CT and MR studies.

Fifteen patients with known metastatic or high-risk primary cancer, normal neurologic examinations, and new abnormalities on 99mTc bone scan were evaluated with spinal CT and magnetic resonance (MR) imaging. Four patients underwent CT metrizamide myelography. Spinal CT and MR agreed in 14 of 15 patients demonstrating spinal metastases in 12 patients and benign disease in two. In one patient spinal CT was normal, but MR showed altered marrow signal consistent with metastatic disease. Epidural tumor was demonstrated by CT metrizamide myelography in four cases, all correctly identified by MR. Further evaluation of spinal MR in this setting is warranted.

Adult↗