Directional electrodes in deep brain stimulation: Results of a survey by the European Association of Neurosurgical Societies (EANS).

Introduction: Directional Leads (dLeads) represent a new technical tool in Deep Brain Stimulation (DBS), and a rapidly growing population of patients receive dLeads. Research question: The European Association of Neurosurgical Societies(EANS) functional neurosurgery Task Force on dLeads conducted a survey of DBS specialists in Europe to evaluate their use, applications, advantages, and disadvantages. Material and methods: EANS functional neurosurgery and European Society for Stereotactic and Functional Neurosurgery (ESSFN) members were asked to complete an online survey with 50 multiple-choice and open questions on their use of dLeads in clinical practice. Results: Forty-nine respondents from 16 countries participated in the survey (n = 38 neurosurgeons, n = 8 neurologists, n = 3 DBS nurses). Five had not used dLeads. All users reported that dLeads provided an advantage (n = 23 minor, n = 21 major). Most surgeons (n = 35) stated that trajectory planning does not differ when implanting dLeads or conventional leads. Most respondents selected dLeads for the ability to optimize stimulation parameters (n = 41). However, the majority (n = 24), regarded time-consuming programming as the main disadvantage of this technology. Innovations that were highly valued by most participants included full 3T MRI compatibility, remote programming, and closed loop technology. Discussion and conclusion: Directional leads are widely used by European DBS specialists. Despite challenges with programming time, users report that dLeads have had a positive impact and maintain an optimistic view of future technological advances.

Dandy-Walker Phenotype with Brainstem Involvement: 2 Distinct Subgroups with Different Prognosis.

BACKGROUND AND PURPOSE: Although cardinal imaging features for the diagnostic criteria of the Dandy-Walker phenotype have been recently defined, there is a large range of unreported malformations among these patients. The brainstem, in particular, deserves careful attention because malformations in this region have potentially important implications for clinical outcomes. In this article, we offer detailed information on the association of brainstem dysgenesis in a large, multicentric cohort of patients with the Dandy-Walker phenotype, defining different subtypes of involvement and their potential clinical impact. MATERIALS AND METHODS: In this established multicenter cohort of 329 patients with the Dandy-Walker phenotype, we include and retrospectively review the MR imaging studies and clinical records of 73 subjects with additional brainstem malformations. Detailed evaluation of the different patterns of brainstem involvement and their potential clinical implications, along with comparisons between posterior fossa measurements for the diagnosis of the Dandy-Walker phenotype, was performed among the different subgroups of patients with brainstem involvement. RESULTS: There were 2 major forms of brainstem involvement in patients with Dandy-Walker phenotype including the following: 1) the mild form with anteroposterior disproportions of the brainstem structures "only" (57/73; 78%), most frequently with pontine hypoplasia (44/57; 77%), and 2) the severe form with patients with tegmental dysplasia with folding, bumps, and/or clefts (16/73; 22%). Patients with severe forms of brainstem malformation had significantly increased rates of massive ventriculomegaly, additional malformations involving the corpus callosum and gray matter, and interhemispheric cysts. Clinically, patients with the severe form had significantly increased rates of bulbar dysfunction, seizures, and mortality. CONCLUSIONS: Additional brainstem malformations in patients with the Dandy-Walker phenotype can be divided into 2 major subgroups: mild and severe. The severe form, though less prevalent, has characteristic imaging features, including tegmental folding, bumps, and clefts, and is directly associated with a more severe clinical presentation and increased mortality.

Hemiparasitic plant impacts animal and plant communities across four trophic levels.

Understanding the impact of species on community structure is a fundamental question in ecology. There is a growing body of evidence that suggests that both subdominant species and parasites can have disproportionately large effects on other organisms. Here we report those impacts for a species that is both subdominant and parasitic, the hemiparasite Rhinanthus minor. While the impact of parasitic angiosperms on their hosts and, to a lesser degree, coexisting plant species, has been well characterized, much less is known about their effects on higher trophic levels: We experimentally manipulated field densities of the hemiparasite Rhinanthus minor in a species-rich grassland, comparing the plant and invertebrate communities in plots where it was removed, present at natural densities, or present at enhanced densities. Plots with natural and enhanced densities of R. minor had lower plant biomass than plots without the hemiparasite, but enhanced densities almost doubled the abundance of invertebrates within the plots across all trophic levels, with effects evident in herbivores, predators, and detritivores. The hemiparasite R. minor, despite being a subdominant and transient component within plant communities that it inhabits, has profound effects on four different trophic levels. These effects persist beyond the life of the hemiparasite, emphasizing its role as a keystone species in grassland communities.

Sacrohysteropexy with synthetic mesh in Aba, South-Eastern Nigeria: a report of three cases and review of the literature.

The surgical treatment of uterovaginal prolapse in women who wish to preserve their uteri for fertility presents a challenge to a gynecologist. This is particularly more challenging in Nigeria and the rest of Africa where there is not only a strong cultural aversion to hysterectomy but women also prefer large family size and male babies. This underscores the need for fertility friendly, uterus-preserving procedures. Three young women under the age of 40 presented with uterovaginal prolapse. They were of low parity and wanted to preserve their uteri for future reproductive function. They had open abdominal suspension of their uteri to the sacrum using a synthetic polypropylene mesh. A pus-string suture was also used to obliterate their pouch of Douglas to prevent future enterocele. Pelvic anatomy was restored and normal vaginal axis was achieved. They had uneventful post-operative period. In resource-limited settings, open abdominal (rather than laparoscopic) sacrohysteropexy with synthetic mesh is an effective and safe alternative to Manchester operation and other vaginal procedures in women who desire to preserve the uterus for future reproductive function.

Are silica defences in grasses driving vole population cycles?

Understanding the factors that drive species population dynamics is fundamental to biology. Cyclic populations of microtine rodents have been the most intensively studied to date, yet there remains great uncertainty over the mechanisms determining the dynamics of most of these populations. For one such population, we present preliminary evidence for a novel mechanism by which herbivore-induced reductions in plant quality alter herbivore life-history parameters and subsequent population growth. We tested the effect of high silica levels on the population growth and individual performance of voles (Microtus agrestis) reared on their winter food plant (Deschampsia caespitosa). In sites where the vole population density was high, silica levels in D. caespitosa leaves collected several months later were also high and vole populations subsequently declined; in sites where the vole densities were low, levels of silica were low and population density increased. High silica levels in their food reduced vole body mass by 0.5% a day. We argue that silica-based defences in grasses may play a key role in driving vole population cycles.

The UCLA population studies of CORD: X. A cohort study of changes in respiratory function associated with chronic exposure to SOx, NOx, and hydrocarbons.

Two never-smoking cohorts in Southern California, one in Lancaster (N = 2340) exposed only to moderate levels of oxidants and the other in Long Beach (N = 1326) exposed to high levels of SOx, NO2, hydrocarbons and particulates completed spirometry and the single-breath nitrogen test five to six years apart. Forty-seven percent and 45 percent of the participants were retested. Mean results at baseline for those tested and not retested were similar. Loss to follow-up was primarily due to moving (39 percent and 47 percent). Every difference of consequence indicated greater deterioration in lung function in Long Beach. The level of significance of the difference was greatest, even in the youngest age groups, for delta N2(750-1250), suggesting that the earliest site of impairment may occur in the small airways. Greater deterioration in spirometric parameters was observed in every age group in Long Beach females above seven years of age at baseline and in Long Beach males above 15 years of age, suggesting that chronic exposure to the pollutant mix occurring in Long Beach ultimately adversely affects the large airways as well as small airways.

The UCLA population studies of chronic obstructive respiratory disease. 9. Lung function changes associated with chronic exposure to photochemical oxidants; a cohort study among never-smokers.

Two cohorts of never-smoking residents of Los Angeles were studied on two occasions five years apart. One cohort (N = 1,099) lived in a community with moderate levels of photochemical pollution and low levels of other pollutants, and the second (N = 1,117) lived in a community with very high levels of photochemical oxidant and relatively high levels of sulfates and particulates. Studies included measurement of forced expiratory volumes and flow rates and single-breath nitrogen washout, as well as use of a standardized questionnaire. The data represent 47 percent of 2,340 and 58 percent of 1,935 residents, respectively, of the original community samples. Mean baseline spirometry and nitrogen washout for those who were and those who were not retested were similar, reflecting the fact that loss to follow-up was primarily due to changes of residence. In the more polluted area there were significantly worse lung function test results for both men and women at baseline and significantly more rapid deterioration at follow-up. Mean changes in nitrogen washout were significantly greater in the more polluted community for both sexes and for all age groups including children. Most of the spirometric test results showed significantly more rapid decline among adults in the more polluted community. These results are consistent with the hypothesis that chronic exposures to a mix of photochemical oxidants, sulfates and particulates are associated with increased loss of lung function, which is especially marked among tests that reflect function of the small airways.

Vasectomy and health. Results from a large cohort study.

In this historical cohort study we identified, located, and, if living, interviewed 10,590 vasectomized men from four cities, along with a paired neighborhood control for each. The times between procedure data and interview or death ranged from under one to 41 years, with median equal to 7.9 years and with 2,318 pairs having ten or more years of follow-up. Participant reports of diseases or conditions that might possibly be related to vasectomy through an immunopathological mechanism were validated by direct contact with physicians and review of medical records. Results of this study do not support the suggestions of immunopathological consequences of vasectomy within the period of follow-up. Except for epididymitis-orchitis, the incidence of diseases for vasectomized men was similar or lower than for their paired controls.

The UCLA population studies of chronic obstructive respiratory disease. VI. Relationship of physiologic factors to rate of change in forced expiratory volume in one second and forced vital capacity.

The mean annualized changes in height (delta height), in forced expiratory volume in one second (delta FEV1), and in forced vital capacity (delta FVC), measured at a 5-yr interval, were determined by year of age for 1,458 residents 7 to 59 yr of age in 2 communities in Los Angeles. The rate of change in delta height, delta FEV1, and delta FVC increased each year until early puberty and then decreased thereafter. The age at which the delta FEV1 and delta FVC reversed from an increasing to a decreasing rate was older in males (13 yr) than in females (11 yr) and lagged about 1 yr behind the age at which rate of delta height reversed. The rate of delta FEV1 and delta FVC sharply declined thereafter until the early 20s, at which age the rate of change leveled off to a constant value. The age at which the delta FEV1 and delta FVC reversed from positive to negative ranged from 21 to 23+ yr, but was probably of less importance physiologically than the age at which the rate of change in delta FEV1 and delta FVC leveled off. The results suggest that growth factors are the major determinants for changes in delta FEV1 and delta FVC until the late teens. From the until the mid-20s, both growth factors and physiologic deterioration may affect delta FEV1 and delta FVC. Thereafter, the primary determinant of delta FEV1 and delta FVC appears to be a gradual but steady decline in physiologic status.

The UCLA population studies of chronic obstructive respiratory disease. IV. Respiratory effect of long-term exposure to photochemical oxidants, nitrogen dioxide, and sulfates on current and never smokers.

Questionnaires, spirometry, and the single-breath nitrogen test were administered to 3,192 participants 25 to 39 yr of age in area exposed to low concentrations of all pollutants (Lancaster, California) and to 2,369 similar participants living in an area exposed to high concentrations of photochemical oxidants, nitrogen dioxide, and sulfates (Glendora, California). The prevalence of symptoms and results in the majority of the tests were worse in the polluted area between current and never smokers and men and women. Those tests associated primarily with small airways (Vmax50, Vmax75, delta N 2(750-1250) showed little or no difference between areas. The difference in the prevalence of participants with a poor FEV1 and/or poor FEV1 and/or poor FVC and in the mean Vmax and closing volume was greater between areas than between smoking categories. These results suggest that long-term exposure to high concentrations of photochemical oxidants, NO2, and sulfates at place of residence may result in measurable impairment in both current smokers and never smokers. Firmer documentation of this effect will require following these populations for changes in lung function that correlate with pollutant exposures.

Cholecystectomy and abdominal hysterectomy.

Cholelithiasis is a common disease in women and can lead to serious complications. At Wilford Hall USAF Medical Center, we have performed 21 cholecystectomies at the time of abdominal hysterectomy. All patients had been asymptomatic with regard to gallbladder disease, but showed either preoperative or intraoperative evidence of gallbladder disease. The mean surgical time was 3.3 hours, mean blood loss was 474 mL, and only one patient had febrile morbidity (> 38.3 degrees C). Because of the low morbidity, we recommend that this combined surgical approach be considered by both the gynecologist and general surgeon.

A common adnexal mass in an uncommon patient: a case report.

Three years after a heart transplant, a woman presented with an adnexal mass that proved to be endometriosis. Her management and its results are presented.

Use of the progestogen challenge test to reduce the risk of endometrial cancer.

In contrast to several retrospective studies reporting an increased risk of endometrial cancer during the mid-1970s, especially in estrogens.gen-treated postmenopausal women, the number of cancers at Wilford Hall USAF Medical Center has steadily declined despite continued estrogen use. In a 4-year study from 1975 to 1978, there were 17 adenocarcinomas of the endometrium during 10,872 patient-years of observation, for an overall annual incidence of 156.4:100,000 women. The highest incidence of endometrial cancer (359.1:100,000) was found in those women using estrogens alone. The lowest incidence of cancer was observed in the estrogen-progestogen users (56.4:100,000) and was significantly lower (P less than .01) than that found in the estrogen users. The incidence of corpus malignancy in the estrogen-progestogen users was also significantly lower (P less than .05) than that observed in the untreated women (248.3:1000,000). The progestogen challenge test has been devised to identify postmenopausal women at greatest risk for adenocarcinoma of the endometrium. It is concluded that the use of this test will reduce the risk of endometrial cancer in both estrogen-treated postmenopausal women and women with increased endogenous estrogens.

Estrogen therapy and breast cancer in postmenopausal women.

During the 6-year period 1972-77, 123 postmenopausal women with breast cancer either had the disease diagnosed at Wilford Hall USAF Medical Center or were referred there for therapy. Their ages ranged from 33 to 90 (mean, 56.6 years). Of these women 64.2 percent had never taken hormones, 25.2 percent were estrogen users, 4.9 percent were estrogen-progestogen users, 4.9 percent had a history of hormone usage, and 1 patient was using estrogen vaginal cream. In a subgroup of 27 clinic patients (1975-77 period) during 14,548 patient-years of observation, breast cancer was diagnosed for an overall incidence of 185.6:100,000 women per year. Among the 27 patients, the annual incidence of breast cancer was highest in the untreated group at 410.5:100,000 women. In comparison, the incidence in the estrogen users was 137.7:100,000 women-a significant difference (p less than 0.01). The incidence in estrogen-progestogen users was 155.6:100,000 compared with the incidence in the untreated patients; this difference was also statistically significant (p less than 0.05). There was no significant difference in the incidence of breast cancer between the estrogen users (137.7:100,000) and the estrogen-progestogen users (155.6:100,000). These data indicate that estrogen therapy decreases the risk of breast cancer and that, unlike the situation with adenocarcinoma of the endometrium, progestogens do not offer additional protection from breast carcinoma.