Detection of a Compact Radio Source near the Center of a Gravitational Lens: Quasar Image or Galactic Core?

By use of a new, very sensitive interferometric system, a faint, compact radio source has been detected near the center of the galaxy that acts as the main part of a gravitational lens. This lens forms two previously discovered images of the quasar Q09S7+561, which lies in the direction of the constellation Ursa Major. The newly detected source has a core smaller than 0.002 arc second in diameter with a flux density of 0.6 +/- 0.1 millijansky at the 13-centimeter wavelength of the radio observations. This source could be the predicted third image of the transparent gravitational lens, the central core of the galaxy, or some combination of the two. It is not yet possible to choose reliably between these alternatives.

Styles of listening and clinical sensitivity.

We report the results of a study of the relation between individual differences in listening style and clinical sensitivity. Listening style is conceptualized as extending from a critical, analytic, focused attitude to a holistic, intuitive, free-floating attitude. Two measures of listening style are used: eye-blink rate and memory for high-imagery words. A tape recording, a 17-minute fragment of a psychotherapy, has been rated by a panel of experts as containing 22 cues reflecting the patient's concern with termination of treatment. This calibrated tape is played to clinicians, and their ability to identify the cues is our experimental measure of clinical sensitivity. It was found that listening style is a strong predictor of clinical sensitivity. The method offers promise for study of a range of issues relevant to therapeutic processes.

Nocturnal slowing of pulsatile luteinizing hormone secretion in women during the follicular phase of the menstrual cycle.

The gonadotropin secretion pattern in normal reproductive age women (n = 5) was evaluated for the presence of a circadian rhythm. The women volunteered for a series of 24-h admissions in different phases of their menstrual cycles (early follicular, late follicular, and midluteal). Plasma LH and FSH levels were determined by RIA in blood samples drawn through indwelling venous catheters at 20-min intervals throughout a normal 24-h sleep-wake cycle. The gonadotropin secretory pattern was subjected to cosine analysis for identifying rhythmicity. The LH interpulse interval fluctuated with a significant 24-h rhythm during the early follicular phase in four of the five women. The maximum interpulse intervals occurred during the early morning between 0100 and 0500 h (mean, 0250 h), with a corresponding increase in LH pulse amplitude occurring within the same time interval (mean, 0320 h). We found no consistent 24-h rhythms in overall mean plasma LH levels during any phase of the menstrual cycle, nor did we find a significant rhythmicity in either LH interpulse interval or LH pulse amplitude during the late follicular or luteal phase. These results demonstrate that the LH pulse-generating system is frequency modulated on a circadian basis during the early follicular phase of the human menstrual cycle.

Luteal phase deficiency: abnormal gonadotropin and progesterone secretion patterns.

Luteal phase deficiency (LPD) is a reproductive disorder associated with infertility and spontaneous abortion. This study was undertaken to determine whether LPD might be related to an abnormal pattern of gonadotropin secretion. We tested this hypothesis by evaluating the pattern of pulsatile LH secretion in both the follicular and luteal phases of the menstrual cycle in normal women (n = 21) and women with LPD (n = 20), which was diagnosed on the basis of two out of phase endometrial biopsies. In addition, we sought to determine whether changes in progesterone (P) pulse patterns could account for the decrease in average serum P levels in women with LPD. To this end, we examined the pulse patterns of P and compared these patterns between normal women and those with LPD. Frequent blood sampling was performed in both groups to determine their respective hormone secretion patterns. In the follicular phase, blood samples were obtained every 10 min for 12 h; in the luteal phase the samples were obtained every 10 min for 12 h; in the luteal LH, FSH, and P were assayed in each sample. Pulse detection was performed by an adaptive threshold method of pulse analysis. The LH pulse frequency was significantly higher in the women with LPD than in the normal women in the early follicular phase [P less than 0.05; LPD, 12.8 +/- 1.4 (+/- SE); normal, 8.2 +/- 0.7 pulses/12 h]. LH pulse frequency was similar in the early and late follicular phases in the women with LPD, whereas it was higher in the late follicular phase in normal women. Mean serum FSH levels were not different between groups in both the early and late follicular phases. In the luteal phase the P pulse amplitude and mean serum P level were significantly lower in the LPD group than in the normal women (P less than 0.01). We conclude that 1) a too rapid LH pulse pattern in the early follicular phase may lead to inadequate LH support of the corpus luteum and become manifest as LPD; 2) the mechanism for inadequate P secretion in LPD is decreased P pulse amplitude; 3) the finding of similar serum FSH levels in the two groups in both the early and late follicular phases did not support compromised folliculogenesis as an etiological factor for LPD.

Progesterone modulation of pulsatile luteinizing hormone secretion in normal women.

Recent studies show that the frequency and amplitude of pulsatile LH secretion change during the normal human menstrual cycle; however, the neuroendocrine mechanisms underlying these changes are poorly understood. To assess the role of progesterone (P) in regulating LH secretion patterns, we treated normal women (n = 5) with im P in oil during the follicular phase of their cycle and compared LH pulse frequency, amplitude, and mean plasma level during treatment to those in normal cycling women. Normal women were studied five times in five menstrual cycles. Each study lasted 24 h, with a sampling interval of 20 min. The cycle phases studied were early follicular (twice), late follicular (LF), midluteal, and LF with P therapy to simulate luteal phase plasma P levels. LH pulse frequency was slower (P less than or equal to 0.001) in the midluteal phase than in either the early follicular phase or LF, and furthermore, P, administered in the normal follicular phase, slowed LH pulse frequency, augmented pulse amplitude, and reduced mean plasma LH levels compared to those in untreated women studied at the same cycle phase (P less than or equal to 0.02). We infer that P secretion by the ovary mediates the change in the LH secretory pattern during the luteal phase of the normal menstrual cycle, and that at least part of this effect is mediated by the central nervous system.

Luteal phase deficiency: characterization of reproductive hormones over the menstrual cycle.

The recurrent deficiency of progesterone (P) secretion by the corpus luteum has been associated with infertility and habitual abortion and given the clinical diagnosis of luteal phase deficiency (LPD). There is evidence that both follicular and luteal phase abnormalities can result in LPD cycles. In this study we have examined reproductive hormone levels and preovulatory follicular size in women with LPD (n = 10). For the purposes of this study, LPD was determined by an endometrial biopsy in the studied cycle that was more than 2 days out of phase. These biopsies were performed in women with infertility or habitual abortion who exhibited an out of phase biopsy in a prior cycle. The control group consisted of 28 normal women. Daily serum levels of the following hormones were determined in each subject: LH and FSH [immuno- and bioactive (LH-immuno and LH-bio)], P, estradiol (E2), and inhibin. The LPD women exhibited significant decreases in integrated luteal phase levels of inhibin [10,615 +/- 898 vs. 13,560 +/- 662 (U/L).days; P less than 0.02] and E2 [5,015 +/- 275 vs. 6,435 +/- 393 (pmol/L).days (1366 vs. 1753 (pg/mL).days); P less than 0.05] in addition to the expected decrease in P [280 +/- 23 vs. 420 +/- 23 (nmol/L).days (88 vs. 132 (ng/mL).days); P less than 0.01]. On days 6-11 after the LH surge (day 0), there was a significant (P less than 0.05) decrease in mean LH-bio levels in LPD compared with those in normal women (146 +/- 26 vs. 212 +/- 24 micrograms/L). The midcycle LH surge was deficient in LPD when both LH-immuno [482 +/- 30 vs. 672 +/- 43 (micrograms/L).days; P less than 0.01] and LH-bio [1711 +/- 179 vs. 2248 +/- 226 (micrograms/L).days; P less than 0.05] levels were compared with normal values. When comparing the follicular phase in LPD with that in normal women, similar follicle size, peak and integrated E2 levels, and mean LH and FSH (immuno and bio) levels were found. The only follicular phase abnormality noted in this study was decreased mean levels of serum inhibin in the early and midfollicular phases (221 +/- 19 vs. 308 +/- 25 U/L; P less than 0.01). In this group of women with LPD, low levels of inhibin in the follicular phase were consistent with the concept of a defect in function of the preovulatory follicle, possibly as a result of previously described defects in gonadotropin secretion in this condition.(ABSTRACT TRUNCATED AT 400 WORDS)

The importance of luteinizing hormone in the control of inhibin and progesterone secretion by the human corpus luteum.

Serum inhibin levels rise markedly during the luteal phase of the human menstrual cycle and are closely correlated with serum progesterone (P) levels, suggesting that the corpus luteum (CL) secretes inhibin. While FSH is the major regulator of inhibin secretion by the granulosa cells, the control of CL inhibin secretion is unclear. We hypothesized that, like P, CL inhibin secretion would be LH dependent. To examine this possibility, normal women were given the GnRH antagonist [Ac-D2Nal1, D4CL Phe2, D3Pal3, Arg5, DGlu6 (AA), DAla10]GnRH (Nal-Glu antagonist) for 3 consecutive days commencing on day 6-8 of the luteal phase. The daily doses were 2.5 (n = 3), 10 (n = 4), and 25 micrograms/kg (n = 5), sc. Serum LH levels fell 2 h after injection, and the fall was maximal (70-74%) at 6 h; the degree of suppression was not dose dependent. The duration of suppression was dose related, being less than 12 h, between 12, and 24 h, and more than 24 h for the 2.5, 10, and 25 micrograms/kg doses, respectively. Serum FSH levels declined by 22-43%, but the effect was not dose related. Serum P levels fell by 42-45% 8 h after each dose of antagonist. They returned to baseline 24 h after the 2.5 micrograms/kg dose, but after both the 10 and 25 micrograms/kg doses serum P levels continued to fall, and menstrual bleeding commenced within 48-72 h after the first antagonist injection. Serum inhibin levels were not altered relative to normal cycles by the 2.5 micrograms/kg dose, but fell by 48% and 58%, and 62% and 73% respectively, 48 and 72 h after the 10 and 25 micrograms/kg doses, respectively. Serum P and inhibin levels correlated closely in all women. To examine the relative roles of FSH and LH in the control of CL function, Nal-Glu antagonist (25 micrograms/kg, sc) was administered at 0 and 24 h commencing on day 6-8 of the luteal phase, in combination with either human menopausal gonadotropin (hMG; 150 IU, im, every 12 h) or hCG (1500 IU, im, once), both commencing at 0 h. hMG administration led to a rapid (by 2 h) and marked (3- to 9-fold) rise in serum FSH levels, whereas serum LH remained low, similar to antagonist alone treatment cycless.(ABSTRACT TRUNCATED AT 400 WORDS)

Onset and characteristics of the midcycle surge in bioactive and immunoactive luteinizing hormone secretion in normal women: influence of physiological variations in periovulatory ovarian steroid hormone secretion.

Limited studies in nonhuman primates suggest that the midcycle LH surge is characterized by distinctly different patterns of bioactive (LH-BIO) and immunoactive (LH-RIA) LH secretion. To further examine the patterns of midcycle LH-BIO and LH-RIA secretion and explore the influence of physiological variations in steroid hormone feedback on LH surge dimensions we studied seven normal ovulatory women over the periovulatory interval. In each, blood samples were obtained every 3 h and transvaginal ultrasonography was performed every 12 h over a 5-7 day interval at midcycle. Serum levels of LH-RIA, FSH, estradiol (E2), progesterone (P4), and 17-hydroxyprogesterone were determined by RIA; LH-BIO was estimated using a mouse leydig cell bioassay. Hormone data were standardized to the time of surge onset in LH-RIA (time zero), defined as a 100% increase above a 6-point running mean baseline value; surge cessation was defined as a decline to below baseline concentration. Mean LH-RIA surge duration was 54.0 +/- 4.0 h. LH-BIO surge onset was simultaneous with that of LH-RIA and coincident with the peak in E2 levels (mean data). Mean P4 and 17-hydroxyprogesterone rose in a parallel, phasic manner, an abrupt increase in slope occurred between -6 h and +30 h but an acute rise in P4 was not consistently observed among individuals. The surge onset to follicle rupture interval (mean 37.6 +/- 4.2 h) positively correlated with peak LH-RIA (r = 0.76, P less than 0.05), surge amplitude (r = 0.74, P less than 0.05) and surge onset to peak interval (r = 0.87, P less than 0.02), but not surge duration. There were no significant relationships between E2 or P4 (mean, peak, integrated, slope) and surge amplitude or duration (LH-RIA, FSH), peak value, or surge onset to peak interval (LH-RIA, LH-BIO, FSH). These data suggest that in women, 1) onset of the midcycle surge in LH-RIA and LH-BIO is simultaneous, and 2) surge characteristics are not influenced by physiological variations in steroid hormone secretion that occur beyond the thresholds required for surge initiation.

Psychiatry takes to the streets: the New York City initiative for the homeless mentally ill.

The authors describe New York City's program to remove seriously mentally ill homeless people from the streets to a public hospital. They report on the 298 patients hospitalized during the first year of this program. Most of the patients were male (66%), single (77%), and from outside of New York City (79%) and claimed a history of previous psychiatric hospitalization (92%) and that they had been homeless for more than 1 year (66%). Most of the patients suffered from schizophrenia (80%) and had additional medical diagnoses (73%). Follow-up contact with the patients 2 years after initiation of the program revealed that 55% of the patients either were living in a community setting or were under institutional care.

Gilles de la Tourette's syndrome. Familial occurrence and precipitation by methylphenidate therapy.

Gilles de la Tourette's syndrome was independently ascertained in two male cousins once removed. Previous studies have shown familial clustering of individuals with tics, but no consistent pattern of inheritance of Tourette's syndrome has been apparent. The onset and later exacerbation of symptoms in our younger patient were associated with the administration of CNS stimulants given for excessive motor activity. The adverse effects of methylphenidate and dextroamphetamine therapy on Tourette's syndrome supports the hypothesis that this condition results from a relative excess of CNS catecholaminergic activity. Physicians prescribing these agents should inquire about the presence of tics in patients and their families.

The corpus luteum: determinants of progesterone secretion in the normal menstrual cycle.

Fourteen normal volunteers were studied during one menstrual cycle. Follicular development, the luteinizing hormone (LH) surge, and the relationship between LH and progesterone secretion in the luteal phase were studied to determine the factors that control corpus luteum function. Follicular development was assessed by measuring follicle size and daily estradiol (E2) levels; the LH surge was quantified by determining the area under the curve. Although there was a significant positive correlation between mean follicle diameter and E2, these same parameters did not correlate with postovulatory progesterone secretion; nor did the LH surge correlate with progesterone secretion. A decrease in LH pulse frequency occurred in moving from the follicular to the luteal phase. There was a trend toward an increase in the late luteal LH pulse frequency compared with the midluteal phase, but this was not significant. Progesterone was secreted in an intermittent (pulsatile) fashion in the midluteal and late luteal phases. The general decrease in progesterone in the latter days of the menstrual cycle appears to be due to a decrease in the progesterone pulse amplitude. A significant correlation between LH and progesterone was present when the data were "smoothed"; however, there was not a significant synchrony for LH and progesterone pulses for most of the subjects when the initial data were analyzed by objective criteria. Progesterone secretion in the luteal phase is quite complex and leads to highly variable serum levels of progesterone when samples are obtained at random from normal women.

Variability of serum prolactin and progesterone levels in normal women: the relevance of single hormone measurements in the clinical setting.

In order to delineate factors contributing to variation in hormone levels, progesterone and prolactin (PRL) levels from 28 normal women, obtained daily during one menstrual cycle and every 20 minutes during a midluteal 24-hour admission in a subgroup of five subjects, provided a data base for analysis of these variables. Pulsatile analysis of the 24-hour data was conducted using an adaptive-threshold algorithm, and normal reference ranges were generated from randomly selected daily hormone values. Our data verify that inherent variation can significantly alter single random serum levels of reproductive hormones. These variations included menstrual cycle day, circadian influence, pulsatile secretion, assay error, and biologic heterogeneity. Besides the expected day-to-day change in progesterone levels during the luteal phase, seven of ten women exhibited a significant circadian variation in progesterone; however, the time of day of the peak level was not consistent among women. Prolactin levels did not demonstrate any clinically relevant change over the menstrual cycle, but did have a consistent circadian pattern (nocturnal rise) over the 24-hour study period. Pulsatile variation occurred in both progesterone and PRL levels during the 24-hour admission. Five different reference ranges were generated from randomly selected single daily values from the 28 normal menstrual cycles. Although the mean levels calculated for each reference range were similar, the reference ranges demonstrated considerable variation due to the random sampling. In the five progesterone reference ranges, the lower limit of the range varied from 2.7-6.1 ng/mL, whereas the upper limit varied from 24.2-42.1 ng/mL.(ABSTRACT TRUNCATED AT 250 WORDS)

Gonadotropin-releasing hormone-induced changes in testosterone secretion in normal women.

This study investigated the pattern of testosterone (T) secretion in spontaneous (n = 14) and gonadotropin-releasing hormone (GnRH)-treated (n = 6) menstrual cycles in normal women. In spontaneous cycles, T was found to increase progressively over the follicular phase (P less than or equal to 0.001), with the peak T value occurring on cycle day 0 (luteinizing hormone [LH] surge). The mean (+/- standard error of the mean [SEM]) T values on cycle day -14 and cycle day 0 were 35 +/- 4 and 51 +/- 4 ng/dl, respectively. GnRH was administered intravenously to six women at 1.3 to 1.7 micrograms per dose every 30 minutes in a study that assessed the ovarian effects of a rapid gonadotropin pulse frequency. In three of the women, the T levels followed a normal follicular phase pattern, whereas in the remaining three GnRH-treated women, there were marked increases in T with peak levels of 97, 123, and 81 ng/dl on day 0. The GnRH-treated subgroup with increased T levels had significantly increased follicular levels of LH, follicle-stimulating hormone (FSH), LH-bio and number of preovulatory ovarian follicles. This study demonstrated that increased levels of LH, FSH, and LH/FSH are capable of acutely increasing the secretion of ovarian androgens.

Medical treatment of endometriosis: a comparison of the suppressive effects of danazol and nafarelin on reproductive hormones.

OBJECTIVE: Patients with endometriosis were studied to investigate hormonal suppression by the gonadotropin-releasing hormone against nafarelin acetate compared with danazol. We hypothesized that the pattern, time course, and degree of gonadotropin and ovarian suppression would be different. DESIGN: The study included 16 patients who were randomized into one of three 6-month treatment protocols. SETTING: Patients were recruited from a university hospital setting. PATIENTS: Eligible candidates were 18 to 45 years of age, with regular menses and documented pelvic endometriosis. INTERVENTION: Six-month treatment protocols included nafarelin 800 or 400 micrograms/d, or danazol 800 mg/d. MAIN OUTCOME MEASURES: Serum estradiol (E2), progesterone (P), luteinizing hormone (LH), and follicle-stimulating hormone were determined before treatment and then monthly. Thirteen patients consented to a 12-hour hospital admission during the 5th and 6th month of treatment to determine LH pulse frequency and amplitude. RESULTS: Estradiol and P were suppressed in all groups, but E2 significantly more by nafarelin than danazol (P less than or equal to 0.01). Nafarelin, 800 micrograms, significantly depressed LH pulse amplitude compared with danazol (P less than or equal to 0.05). Two patients in the nafarelin group had the administration of their medication observed, and both demonstrated single, high-amplitude pulses immediately after administration. CONCLUSION: Nafarelin is a more potent LH and E2 suppressor than danazol, and the agonist effect of nafarelin may continue to provoke transient gonadotropin responses despite long-term therapeutic suppression.

Postoperative imaging of the multichannel cochlear implant.

PURPOSE: To present the postoperative radiographic appearance of the multichannel cochlear implant and to suggest criteria for the radiographic evaluation of postimplant patients. METHODS: One hundred forty-one patients, 73 female and 68 male, had multichannel cochlear implants inserted. One hundred thirty-five intraoperative radiographs, 31 postoperative radiographic examinations, and 10 postoperative CT examinations were retrospectively reviewed. RESULTS: In 135 patients, a Stenver's or anteroposterior projection confirmed the normal placement of the implant by demonstrating the electrodes to be regularly spaced and gently curved within the first turn of the cochlea. The insertion depth was determined by counting the number of electrodes that projected medial to the cochlear promontory. In 5 patients in whom intracochlear placement of the electrode array could not be confirmed on plain radiographs, CT demonstrated the location of the electrode array. In 3 patients with postoperative infections, CT either correctly identified or excluded the presence of a collection beneath the implant. CONCLUSION: Plain radiographs of the temporal bone are sufficient for the postoperative treatment of the majority of postimplant patients. CT should be performed when plain radiographs cannot adequately show the location of the electrode array or if postoperative infection is suspected.

The dizzy patient. Update on vestibular disorders.

Dizziness is often a patient's shorthand description of a variety of symptoms, many of which have nothing to do with balance. Vertigo consists of an abnormal sensation of motion, whereas dysequilibrium is a disturbance of balance without necessarily a sensation of motion. A careful history usually determines the nature of the patient's presenting symptoms, and a thorough workup will often give rise to a diagnosis. Vertigo of vestibular origin may be treated with a variety of medications or, when these fail, surgery. Surgery should preserve hearing when at all possible. Balance rehabilitation is a useful modality for the patient who does not compensate spontaneously or who does not respond to the medical or surgical treatment of imbalance.

Teflon injection for vocal cord paralysis after intracranial operation.

Vocal cord paralysis may follow intracranial operation if the vagus nerve is damaged intraoperatively. If the resulting laryngeal incompetence is severe, hoarseness, dysphagia, and aspiration may develop. This is often followed by a pneumonitis requiring chronic gastric tube feeding. Teflon vocal cord injection has been shown to restore the sphincteric action of the larynx and enable patients to phonate and swallow properly again. Nine patients underwent this procedure for chronic aspiration and hoarseness. All had vagus injury attributable to antecedent intracranial operation, and all experienced relief of their symptoms with only minor complications. Teflon vocal cord injection is advocated as a safe, effective means of managing patients with aspiration and dysphagia secondary to vagus nerve injury.

Food safety training needs exist for staff and consumers in a variety of community-based homes for people with developmental disabilities.

OBJECTIVE: To determine staff and consumer-focused food safety training needs in community-based homes for people with developmental disabilities as well as dietitians' perceptions of food-handling practices in these homes. DESIGN: Direct-care staff and dietitians were surveyed according to a modified Dillman method using a mailed, self-administered questionnaire. Main outcome measures included food-handling knowledge, attitudes, and practices of staff and consumers as reported by staff and dietitians; critical control points in safe food preparation in the homes based on the Hazard Analysis and Critical Control Point system; and learning preferences of staff and consumers. SUBJECTS: A 10% probability sample of direct-care staff in homes for people with developmental disabilities in western Massachusetts and a nonprobability sample of dietitians who work with this population were surveyed. Results are reported from 132 and 18 respondents, respectively. STATISTICAL ANALYSES PERFORMED: Descriptive statistics, chi 2 statistic, and the Fisher's exact test. RESULTS: Staff knowledge of safe food preparation is lacking in several areas, including storage and handling procedures. Although staff and consumers do not always follow safe food-handling practices, the staff reported that they follow recommended food-handling practices more often than the dietitians reported they do. Most staff and dietitians reported that staff and consumers had never attended a food safety training program, but that all of the critical control points surveyed would be somewhat helpful if they were included in a food safety workshop. APPLICATIONS: A food safety training program would be beneficial for staff and consumers. Programs should be geared to staff and include ideas and materials for consumers. Consumer modules could then be adapted to individual learning levels by direct-care staff in the homes. The Safe Food at Home workshop was developed on the basis of the results of this study and incorporates the approaches described in this article.

Electroencephalographic analysis: a methodology for evaluating psychotherapeutic process.

The relationship between individual differences in listening style and clinical sensitivity was studied. Listening style is conceptualized as extending from a critical, analytic, focused attitude to a holistic, intuitive, free-floating attitude. We studied the listening styles of psychiatric residents while they listened to a tape recording, a 17-minute fragment of a psychotherapy that had been rated by a panel of experts as containing 22 cues reflecting the patient's concern with termination of treatment. The ability of clinicians to identify these cues is our experimental measure of clinical sensitivity. Our measures of listening style include eyeblink rate, memory for high-imagery words, and electroencephalogram recorded from electrodes over the right and left temporal areas, all measured while psychiatric residents listened to the tape. Results suggested that an abundance of alpha indicates a readiness on the part of the listener to process clinically relevant information. In addition, a listening style with engagement of the right hemisphere predicted clinical sensitivity. These findings suggest ways to study how the skilled clinician "tunes" himself empathically to his patient.

Acoustic neuroma surgery with emphasis on preservation of hearing.

A review is presented of 34 cerebellopontine angle tumors surgically removed between 1973 and 1978 by the author at the New York University Medical Center. A diagnostic protocol is outlined: An acoustic PEG (small volume pneumoencephalogram with polytomography) is utilized where a medium to large tumor is suspected, and a Pantopaque fossagram for the smaller tumors. Indications are given for the middle fossa, translabyrinthine and suboccipital approaches, depending on tumor size and level of hearing. Hearing was successfully preserved at or near the preoperative level in 3 of 6 extracanalicular tumors operated upon using the suboccipital microsurgical approach. Audiometric data are given, demonstrating the preservation of hearing. The surgical technique is described. There were no fatalities in the entire series. The incidence of permanent facial nerve palsy was 8%. Nerve palsy occurred in large tumors only.