The MRI appearance of the optic nerve sheath following fenestration for benign intracranial hypertension

Optic nerve fenestration is carried out in cases of severe benign intracranial hypertension. This study aimed to monitor the optic nerve sheath appearances and orbital changes that occur following this procedure. The eight patients were all female with an average age of 37.3 years and a range of 20-58 years. The duration of symptoms was 2-6 years. Symptoms included headaches, diplopia and visual obscurations. Examination revealed severe papilledema. All investigations, including MRI, biochemical and immunological tests, were negative. Patients had fenestration of a 2 mm x 3 mm segment of the medial aspect of the optic nerve sheath. Imaging was obtained with a 1 T MRI machine using a head coil. Coronal, axial and sagittal 3 mm contiguous sections using STIR sequences with TR 4900 ms, IT 150 ms and TE 60 ms were obtained. Five patients showed clinical improvement. The post-operative MRI findings in four of these included a decreased volume of cerebrospinal fluid (CSF) around the optic nerve sheaths and a localized collection of fluid within the orbit. There were no MRI changes in the three patients with no clinical improvement. Decreased CSF volume around the optic nerve and a fluid collection within the orbit may indicate a favorable outcome in optic nerve fenestration.     

Activation of amylin gene transcription by LIM domain homeobox gene isl-1

The main objective of the Ambulatory Blood Pressure and Treatment of Hypertension (APTH) trial is to test the hypothesis that antihypertensive treatment based on ambulatory monitoring may be more beneficial than treatment guided by conventional sphygmomanometry. After a 2-month run-in period on single-blind placebo, hypertensive patients were randomized to two groups, one in which the target pressure was a sitting diastolic pressure from 80 through 89 mm Hg on conventional sphygmomanometry (conventional blood pressure [CBP] group), and one in which a daytime (from 10 to 20 h) diastolic pressure from 80 through 89 mm Hg had to be achieved (ambulatory blood pressure [ABP] group). After randomization all patients were started on lisinopril 10 mg/day. One month later lisinopril could be continued at 10 or 20 mg/day or discontinued depending on the attained blood pressure level. This article is an interim report on 207 patients followed for two months into the trial. At one month lisinopril was discontinued more frequently in the ABP than the CBP group (24 vs 9 patients, p = 0.004). Nevertheless at two months, blood pressure control was not significantly different in the two treatment groups. The baseline-adjusted differences in systolic pressure between the two treatment arms of the trial (ABP-CBP group) were +2.7 mm Hg (95% confidence interval [CI]): -2.9, +8.3) for the conventional pressure, +0.4 mm Hg (CI: -4.3, +5.1) for the 24 h pressure, -0.1 mm Hg (CI: -5.1, +4.8) for the daytime pressure and -0.7 mm Hg (CI: -6.7, +5.4) for the night-time pressure. The corresponding differences in diastolic pressure were -1.3 mm Hg (CI: -4, +1.4), +0.1 mm Hg (CI: -3, +3.1), -1.1 mmgH (CI: -4.4, +2.1) and +0.3 mm Hg (CI: -3.7, +4.3), respectively. Thus, the present findings do not refute the APTH research hypothesis. In terms of blood pressure control and the number of patients remaining on antihypertensive drugs, treatment based on ambulatory recordings may be preferable to treatment guided by conventional sphygmomanometry.     

Regional myocardial motion and thickening assessed at rest by ECG-gated 99mTc-MIBI emission tomography and by magnetic resonance imaging

We have validated ECG-gated emission tomography using technetium-99m methoxyisobutylisonitrile for the assessment of regional ventricular function by comparing it with cine magnetic resonance imaging (MRI). Gated tomography was performed at rest in 24 patients referred for myocardial perfusion imaging [17 males and seven females with a mean age of 58 years, nine of whom had had a previous myocardial infarction (MI)]. Scores were assigned to each of nine myocardial segments for wall motion and for thickening. Cine MRI was analysed in an identical fashion. Four out of 216 (2%) segments were uninterpretable by gated tomography because of inadequate tracer uptake. In eight patients without coronary artery disease (CAD), wall motion and thickening were normal by both methods. Gated tomography showed abnormal wall motion or thickening in all patients with previous MI and in five of seven patients with CAD but no prior MI. Association between wall motion and thickening was good (rs=0. 86). Overall, there was good agreement between gated tomography and MRI for both wall motion (178/212 segments, kappa=0.66) and wall thickening (184/212 segments, kappa=0.69). In segments with severely reduced perfusion, however, there was poorer agreement (kappa=0.31). Interobserver and intraobserver agreement was high (kappa from 0.61 to 0.78). Thus, in patients investigated for CAD, there is good overall agreement between gated tomography and MRI but the agreement is lower in segments with severe perfusion defects.     

The duration of estradiol and progesterone exposure prior to progesterone withdrawal regulates oxytocin mRNA levels in the paraventricular nucleus of the rat

The nonapeptide oxytocin (OT) is important for milk ejection during lactation, uterine contractility at parturition, and the onset of maternal behavior. Sequential exposure to estradiol (E2) and progesterone (P) followed by P withdrawal increases OT mRNA in the paraventricular nucleus (PVN), and to a lesser degree the supraoptic nucleus (SON), of the rat 48 hours after the P is removed. Although increases in PVN OT mRNA are not accompanied by changes in posterior pituitary OT peptide content, the PVN contains OT neurons that project to both the posterior pituitary (magnocellular group) and extra pituitary sites (parvocellular groups). Steroid-induced increases in OT mRNA occur in both the magnocellular and the parvocellular regions of the PVN. The latter are believed to contribute to CNS release of OT which may be important for certain behaviors including the onset of maternal behavior. The same steroid sequence that increases PVN OT mRNA also induces maternal behavior in virgin ovariectomized rats. Exposure of animals to E2 and P for 2 weeks resulted in the shortest latency to the onset of maternal behavior in ovariectomized rats, whereas exposure for 6 days was associated with a longer latency. In this study we questioned if the duration of E2 and P exposure prior to P withdrawal is an important regulator of PVN OT mRNA levels. We compared OT mRNA levels in the PVN of virgin ovariectomized rats administered no steroid or sequential E2 and P for 2 weeks versus 6 days. On day 1 animals received steroid-filled or empty capsules followed by P-filled or empty capsules on day 3. In one steroid-treated group, E2 and P were continued for 6 days and in the other group for 14 days prior to P removal. Animals were sacrificed 48 hours after P removal. Levels of OT mRNA were compared among 6 day and 2 week steroid-treated animals and sham-treated animals. The relative abundance of OT mRNA was significantly increased, P < 0.05, in animals receiving the 2-week, but not the 6-day, steroid treatment compared to sham-treated animals. Pituitary OT peptide content was not significantly different among the three groups. We conclude that the duration of steroid exposure may be an important regulator of the level of OT mRNA in the PVN of the rat.     

The application of radionuclide infarct scintigraphy to diagnose perioperative myocardial infarction following revascularization

To evaluate the application of radionuclide infarct scintigraphy to diagnose myocardial infarction after revascularization, we obtained postoperative technetium 99m pyrophosphate myocardial scintigrams, serial electrocardiograms and CPK-MB isoenzymes in ten control and 51 revascularized patients. All control patients had negative electrocardiograms and scintigrams, but eight had positive isoenzymes. Eight revascularized patients had positive electrocardiograms, images and enzymes and two had positive scintigrams and enzymes with negative electrocardiograms. Thirty-four patients with negative electorcardiograms and scintigrams had positive isoenzymes; in only seven patients were all tests negative. Our data suggest radionuclide infarct scintigraphy is a useful adjunct to the electrocardiogram in diagnosing perioperative infarction. The frequent presence of CPK-MB in postoperative patients without other evidence of infarction suggests that further studies are required to identify all factors responsible for its release.     

The descriptive epidemiology and trends in incidence of nonocular malignant melanoma in Bombay and India

Nonocular malignant melanoma is a rare but lethal disease increasing in incidence and mortality in western countries with improved survival if diagnosed and treated early. This study reports its epidemiology from cancer registry data in six different parts of India; its anatomic distribution and trends in Bombay from 1964 to 1984. Age-adjusted incidence in Bombay patients shows no increase from 1964 to 1984 unlike in white caucasians. Males exceed females in patients 45 years or older unlike whites, but are equalled or exceeded by females in those less than 45 years. The sole of foot and internal mucous membranes are its major anatomic sites in Indians as in negroid blacks. This cancer in Indians resembles that in blacks and nonwhites in affecting less pigmented epithelia and skin. Susceptible melanosomes and ultraviolet light exposure may both be involved in its aetiopathogenesis.     

Longitudinal analysis of deciduous tooth emergence: II. Parametric survival analysis in Bangladeshi, Guatemalan, Japanese, and Javanese children

We present a form of parametric survival analysis that incorporates exact, interval-censored, and right-censored times to deciduous tooth emergence. The method is an extension of common cross-sectional procedures such as logit and probit analysis, so that data arising from mixed longitudinal and cross-sectional studies can be properly combined. We extended the method to incorporate and estimate a proportion of agenic teeth. While we concentrate on deciduous tooth emergence, the method is relevant to studies of permanent tooth emergence and other developmental events. Deciduous tooth emergence data were analyzed from four longitudinal studies. The samples are 1,271 rural Guatemalan children examined every three months up to age two and every six months thereafter as part of the INCAP study; 397 rural Bangladeshi children examined monthly to age one and quarterly thereafter as part of the Meheran Growth and Development Study; 468 rural Indonesian children examined monthly as part of the Ngaglik study; and 114 urban Japanese children examined monthly in studies from 1910 and 1920. Although all four studies were longitudinal, many observations from the Guatemala and Bangladesh studies were effectively cross-sectionally observed. Three different parametric forms were used to model the eruption process: a normal distribution, a lognormal distribution, and a lognormal distribution with age shifted to shortly after conception. All three distributions produced reliable estimates of central tendencies, but the shifted lognormal distribution produced the best overall estimates of shape (variance) parameters. Estimates of emergence were compared to other studies that used similar methods. Japanese children showed relatively fast emergence times for all teeth. Bangladeshi and Javanese children showed emergence times that were slower than are found in most previous studies. Estimates of agenesis were not significantly different from zero for most teeth. One or two central incisors showed significant agenesis that ranged from 0.1 to 0.8% in three of the samples; even so, failure to model the agenic proportion did not seriously bias the estimates.