Volumetrical measurements in vestibular schwannoma, the influence of slice thickness and patient's repositioning.

OBJECTIVE: Conservative treatment in vestibular schwannomas is mainly dependent on optimal tumor size determination. The first objective of this study was to establish interobserver and intraobserver variability and the accuracy and reproducibility of three different measurement methods: one bidimensional and two volumetrical. The second objective was to evaluate the influence of the use of different magnetic resonance imaging (MRI) slice thickness and the influence of patient's repositioning on the measurements' outcome. STUDY DESIGN: Two consecutive studies have been prospectively performed, both mainly concerning volumetrical measurements. SETTING: Both studies were performed in a tertiary academic, multidisciplinary center. PATIENTS: In the first study, 19 patients were included between March 1996 and May 2002, with a total of 52 scans. The second study comprised 14 patients. All patients in the first study had at least two MRI examinations performed according to a standard protocol (T1-weighted gadolinium-enhanced, slice thickness of 3 mm, and interslice gap of 0.3 mm). The population in the second study underwent a conservative wait and scan (W&S) treatment. METHODS: Both studies are discussed separately. In the first study, all scans were measured by four investigators, two of whom performed the measurements twice using three different methods. The first method concerns a manually performed bidimensional surface measurement along the petrous pyramid. The second method concerns a semiautomatic volumetrical measurement on a computer, relying on contour detection, and the last method concerns a fully automatic volume reconstruction also performed on a computer using different gray shade scales.All 14 patients included in the second study underwent three magnetic examinations. Three different T1-weighted gadolinium-enhanced sequences were used: the first using a slice thickness of 1 mm, the second again with 1-mm slice thickness but after having repositioned the patient. In the third sequence, a slice thickness of 3 mm was used. All scans were measured by two investigators using the three different methods, as described previously. RESULTS: The manual surface method shows large intraobserver variability, and its reproducibility is significantly lower compared with volume measurements. Because of a relatively large systematic error in small tumors, sensitivity of growth detection is low. Both volumetrical methods are hardly interobserver- and intraobserver-dependent, and the gray shade method turned out to be the most accurate. Radiologic progression is only significant at a volume increase of at least 50%. The influence of patient repositioning is negligible, whereas the use of 1-mm slice thickness seems to be superior to a 3-mm slice thickness. CONCLUSION: The volumetrical gray shade method is the most accurate method to detect early tumor progression. As tumor increase of at least 50% is needed to be able to speak of statistically significant tumor growth, the absence of radiologic progression does not mean that there is no tumor growth. Repositioning of the patient has no influence on the measurements' outcome, whereas for optimal magnetic resonance imaging examinations, a 1-mm slice thickness protocol seems to be superior.     

Intratemporal facial nerve transfer with direct coaptation to the hypoglossal nerve.

OBJECTIVE: To evaluate functional recovery after facial-hypoglossal nerve transfer with direct coaptation of the intratemporal part of the facial nerve. STUDY DESIGN: Retrospective study. SETTING: University-based tertiary referral center. PATIENTS: Nine patients who underwent facial-hypoglossal transfer surgery between 2001 and 2006 to treat a unilateral complete facial nerve palsy. INTERVENTION: The facial nerve is mobilized in the temporal bone, transsected at the second genu, transferred and directly coaptated to a partially incised hypoglossal nerve. MAIN OUTCOME MEASURES: The House-Brackmann grading system was used to evaluate facial nerve reinnervation. Tongue atrophy and movements were documented. Quality of life related to facial function was assessed using the validated Facial Disability Index. RESULTS: A House-Brackmann Grade III (86%) was achieved in six patients, and Grade IV (14%) in one patient with an average follow-up of 22 months (range, 12-48 mo). Two patients had a follow-up of less than 12 months after surgery, and reinnervation was still in progress. In none of the patients who were operated on was tongue atrophy or impaired movement observed. Postoperative Facial Disability Index scores (mean, 71.8 +/- standard deviation [SD] 10.6) for physical functioning and social functioning (mean, 85.7 +/- SD 9.8) were increased for all patients when compared with preoperative scores (mean, 28.6 +/- SD 9.0; mean, 37.7 +/- SD 14.4, respectively). CONCLUSION: The facial-hypoglossal nerve transfer with direct coaptation of the intratemporal part of the facial nerve offers good functional results with low lingual morbidity and improved quality of life. The technique is straightforward, relatively simple, and should be considered as first option for reanimation of traumatic facial nerve lesions.     

New digital method for quantitative assessment of nasal morphology.

Our aim was to develop and validate a new method to assess objectively and quantitatively the morphology of the nostrils after nasal or nasolabial surgery. We used digital analysis using specific mathematical algorithms to assess several geometric measurements, particularly of facial asymmetry, expressed in adimensional units. Forty-five patients with no facial anomalies (control group) were used initially to evaluate the method and to obtain variables for statistical reference. Thirty-five patients operated on for unilateral cleft lip and palate (cleft group) were then analysed and compared with the control group. Individual scores were obtained for each patient, computed, and correlated with those established by a lay panel. Statistical analysis showed good sensitivity and reliability (R>0.8).     

Coemployed spouses: differences,strategies, and discrimination

The authors explore linkages between family and work roles. They examine patterns of apparent economic strategies of spouses working at a southern university located in a rural area. Their research focuses on spousal economic behavior and specifically addresses the effects of spouses' dual employment on the job status of women, differences between spouses in the timing of education and 1st hire at the university, status consistencies in husband and wife employment levels, and sexual discrimination in job levels and income of coemployed spouses. The study uses data extracted from a personnel data set. Cases from a computerized file were identified in 1980-1981, analyzed with 1981-1982 data, and compared with total work force data for 1982-1983. Slightly more than 1/2, or 123 identified cases, were analyzed. Some study findings follow. 1) Marriage to a coemployed spouse is associated with high occupational levels for female employees. 2) It is the husband's career that generally dictates the entry of a couple into the university's internal labor market. 3) There seems to be a strain toward consistency in the status levels of married pairs. 4) Collaborative strategies are being used to secure economic advances for the family unit. Major efforts regarding education and job selection are directed toward advancing the husband's career preference. However, some exceptions suggest that the pattern is flexible and that economic factors will take precedence over stereotyped sex roles when family needs come into consideration. 5) There is employment discrimination by sex at all levels of the internal labor market being studied. Status and income differentials still exist between males and females. Males in the same occupational statuses are paid more than their female counterparts. Females are concentrated at the lower levels of occupational ranks, males toward the top. Although this study is preliminary, it provides partial support for previous research on coemployed spouses' patterns of educational and occupational attainment, and the persistence of sex discrimination in earnings and occupational prestige.     

Relative sensitivity of four noninvasive methods in assessing systolic cardiovascular effects of isoproterenol in healthy volunteers.

STUDY OBJECTIVE: The study was performed to evaluate the relative sensitivity of various noninvasive methods to detect and describe the systolic cardiovascular effects of stepwise increasing doses of isoproterenol: two-dimensional left ventricular echocardiography (main variable, ejection fraction), ACVF (attenuation compensated volume flow)--dual-beam Doppler echoaortography (time-averaged mean velocity), electrical impedance cardiography [(dZ/dtmax)/RZ index], and systolic time intervals from mechanocardiography (PEP and QS2c). METHODS: Isoproterenol was administered by constant rate intravenous infusion in consecutive steps of 0.1, 0.2, 0.4, 0.75, and 1.5 micrograms/min (each for 15 minutes). Saline control infusions were given in analog fashion. The treatments (isoproterenol and saline solution) were administered in a period-balanced two-way crossover design with randomly allocated sequences. The subjects, observers, and analysts were blinded to the treatment protocol. Study subjects were 10 healthy male volunteers (age range, 23 to 31 years; mean age, 26.6 years). RESULTS: Compared with saline solution, isoproterenol caused a dose-related increase in ejection fraction, (dz/dt)/RZ index, and time-averaged mean velocity and a dose-related shortening of PEP and QS2c. The responses are congruent with an enhancement of cardiac systolic performance caused by a positive inotropic stimulation and an afterload reduction ("inodilatory" response). The effects on systolic time intervals reached statistical significance (alpha = 0.05) at the first isoproterenol dose step, the effects on the impedance cardiography and the Doppler echoaortography variables reached statistical significance at the second dose step, and the effects on the two-dimensional echocardiography reached statistical significance at the third dose step. CONCLUSIONS: All methods allowed to detect isoproterenol-related changes. Systolic time intervals were the most sensitive, followed by impedance cardiography, ACVF--dual-beam Doppler echoaortography, and two-dimensional echocardiography. The practical convenience and high sensitivity of the systolic time intervals makes them suitable to evaluate investigational systolic inodilatory changes in humans.     

Retinal dehydrogenase-2 is inhibited by compounds that induce congenital diaphragmatic hernias in rodents

Currently, the etiology of the serious developmental anomaly congenital diaphragmatic hernia (CDH) is unknown. We have used an animal model of CDH to address this issue. We characterized four separate teratogens that produced diaphragmatic defects in embryonic rats that are similar to those in infants with CDH. We then tested the hypothesis that all these agents share the common mechanism of perturbing the retinoid-signaling pathway. Specifically, inhibition of retinal dehydrogenase-2 (RALDH2), a key enzyme necessary for the production of retinoic acid and that is expressed in the developing diaphragm, was assayed by measuring retinoic acid production in cytosolic extracts from an oligodendrocyte cell line. The following compounds all induce posterolateral defects in the rat diaphragm; nitrofen, 4-biphenyl carboxylic acid, bisdiamine, and SB-210661. Importantly, we demonstrate that they all share the common mechanism of inhibiting RALDH2. These data provide an important component of mounting evidence suggesting that the retinoid system warrants consideration in future studies of the etiology of CDH.     

Iron and fur regulation in Vibrio cholerae and the role of fur in virulence

Regulation of iron uptake and utilization is critical for bacterial growth and for prevention of iron toxicity. In many bacterial species, this regulation depends on the iron-responsive master regulator Fur. In this study we report the effects of iron and Fur on gene expression in Vibrio cholerae. We show that Fur has both positive and negative regulatory functions, and we demonstrate Fur-independent regulation of gene expression by iron. Nearly all of the known iron acquisition genes were repressed by Fur under iron-replete conditions. In addition, genes for two newly identified iron transport systems, Feo and Fbp, were found to be negatively regulated by iron and Fur. Other genes identified in this study as being induced in low iron and in the fur mutant include those encoding superoxide dismutase (sodA), fumarate dehydratase (fumC), bacterioferritin (bfr), bacterioferritin-associated ferredoxin (bfd), and multiple genes of unknown function. Several genes encoding iron-containing proteins were repressed in low iron and in the fur mutant, possibly reflecting the need to reserve available iron for the most critical functions. Also repressed in the fur mutant, but independently of iron, were genes located in the V. cholerae pathogenicity island, encoding the toxin-coregulated pilus (TCP), and genes within the V. cholerae mega-integron. The fur mutant exhibited very weak autoagglutination, indicating a possible defect in expression or assembly of the TCP, a major virulence factor of V. cholerae. Consistent with this observation, the fur mutant competed poorly with its wild-type parental strain for colonization of the infant mouse gut.     

Effects of Behavioral Control and Type A Behavior on Cardiovascular Responses

The purpose of this study was twofold: (a) to examine the relationship between degree of behavioral control and cardiovascular changes in 60 adult males performing an anagram solution task, and (b) to assess the interaction between behavioral control and type of subject (A vs. B). Three conditions were used, differing from each other in the percentage of solvable anagrams (100, 50, and 30%). Systolic blood pressure (SBP), diastolic blood pressure (DBP), and heart rate (HR) were measured before, during, and after the anagram task. In all conditions, during-task SBP, DBP, and HR were significantly elevated above baseline. Blood pressure (BP) elevations appeared to be curvilinearly related to degree of behavioral control, i.e., more elevated in the 50% than in the 100% and 30% conditions. HR changes did not differ among conditions. Concerning the Type A behavior pattern, the results revealed significantly greater BP elevations for Type A than for Type B subjects, especially in the 50% condition, thereby confirming that the physiologic correlates of Type A behavior are predominantly evoked in challenging circumstances. Findings were discussed in the light of results of cardiovascular and endocrinological research. Consideration was given to the possible role of disengagement in the 30% condition and to differences in the pattern of responding between As and Bs.     

Trigeminal neuropathy and partial nose destruction

Summary Two cases of trigeminal neuropathy with tissue loss are described, one in a Spillane-Wells syndrome, the other in a Riley-Day syndrome. Although the etiology was different, nose-picking led in both cases to a typical punchedout lesion of the skin and cartilage of nose tip, columella and alae nasi. Reconstruction was performed only in the first case, after resolution of the neuropathy. Reconstruction should not be considered for cases with persistant anaesthesia.Head: M. Lejour