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1.
Thirty-two Hispanic speakers of English were evenly divided into two groups based on whether or not their initial learning of English began prior to, or after the age of 12 years. Each group had an even number of males (16) and females (16). The subjects were recorded producing a protocol of 18 basic speech syllables. The first three repetitions (54 tokens) were chosen for analysis. The 1728 tokens were digitized and measured for voice onset time (VOT). Findings support the hypothesis that the VOT values of Hispanics speaking English differ according to whether initial learning of English began prior to or after the age of 12 years. An analysis of variance (ANOVA) found significant main effects of group, place, voice, and gender. Significant interactions were group by voice, and voice by gender. 相似文献
2.
MT Bardella M Quatrini M Zuin M Podda L Cesarini P Velio P Bianchi D Conte 《Canadian Metallurgical Quarterly》1997,92(9):1524-1526
BACKGROUND: An association between celiac disease and primary biliary cirrhosis has been reported in a few cases, mainly as individual case reports. OBJECTIVES: To screen adult patients with celiac disease for primary biliary cirrhosis and patients with primary biliary cirrhosis for intestinal celiac involvement. METHODS: The celiac group consisted of 336 adults (218 women and 118 men; mean age, 36 yr; range 18-74 yr) with celiac disease diagnosed by serological and histological tests, 38 with newly diagnosed celiac disease and 298 with previously diagnosed celiac disease who were consuming a gluten-free diet. The mean follow-up period was 6 yr (range, 1-16 yr). Liver function parameters and autoantibody levels were determined, and, when indicated, histological tests were performed. The biliary cirrhosis group consisted of 65 subjects (58 women and seven men) (mean age, 59 yr; range, 35-67 yr) with primary biliary cirrhosis diagnosed 1-17 years previously (mean, 7 yr) on the basis of the usual biochemical, serological, and histological criteria. Antigliadin and antiendomysium antibody levels were determined, and two biopsy specimens from the distal duodenum obtained during endoscopy were evaluated. RESULTS: In patients with celiac disease, impairment of liver function was frequently found at diagnosis (16 of 38, or 44%), but primary biliary cirrhosis was diagnosed in only one case. In patients with primary biliary cirrhosis, no cases of celiac disease, as currently defined, were found. CONCLUSIONS: Our findings indicate that celiac disease and primary biliary cirrhosis are rarely associated and support the hypothesis that the intestinal lesions per se are not responsible for the liver disease. 相似文献
3.
Medical therapy for women in the perimenopausal period is controversial, in part due to varying degrees of ovarian hormone secretion characteristic of this time of life. To extend our understanding of the reproductive endocrine milieu of perimenopausal women, we studied 6 cycling women, aged 47 yr and older, for 6 months with daily collections of first morning voided urine. Five additional older reproductive aged (43-47 yr old) women were studied with daily urine and serum sampling for a single menstrual cycle; their urinary hormone data were combined with the former group for menstrual cycle comparisons. Urine was assayed for LH, FSH, estrone conjugates, and pregnanediol glucuronide and normalized for creatinine (Cr). Eleven midreproductive aged (19-38 yr old) normally cycling women, 5 women with well defined premature ovarian failure, and 5 women aged 54 yr and older who were at least 1 yr postmenopausal were used for comparison. Perimenopausal women had shorter follicular phases (11 +/- 2 days vs. 14 +/- 1 days; P = 0.031) and, hence, shorter menstrual cycles than midreproductive aged controls. FSH excretion in perimenopausal women was greater than that in younger women (range of means, 4-32 vs 3-7 IU/g Cr; P = 0.0005). LH secretion was overall greater than that in younger normal subjects (range of means, 1.4-6.8 vs. 1.1-4.2 IU/g Cr; P < 0.026). Overall mean estrone conjugate excretion was greater in the perimenopausal women compared to that in the younger women [76.9 ng/mg Cr (range, 13.1-135) vs. 40.7 ng/mg Cr (range, 22.8-60.3); P = 0.023] and was similarly elevated in both follicular and luteal phases. Luteal phase pregnanediol excretion was diminished in the perimenopausal women compared to that in younger normal subjects (range for integrated pregnanediol, 1.0-8.4 vs. 1.6-12.7 microg/mg Cr/luteal phase; P = 0.015). Compared to postmenopausal women, perimenopausal women had more overall estrone excretion (2.5-6.2 ng/mg Cr in postmenopausal women; P = 0.02) and lower mean FSH (range of means for postmenopause, 24-85 IU/g Cr; P = 0.017) and LH (range for postmenopause, 4.3-14.8 IU/g Cr; P = 0.041). Compared to women with premature menopause, perimenopausal women again had lower FSH (range of means for premature menopause, 36-82 IU/g Cr; P = 0.0022), lower LH (range of means for premature menopause, 5.5-23.8 IU/g Cr; P = 0.0092), borderline higher mean estrone conjugates (range of means for premature menopause, 4-44 ng/mg Cr; P = 0.064), and far longer periods of ovarian activity (one to two cycles in prematurely menopausal women vs. three to six cycles in perimenopausal women). We conclude that altered ovarian function in the perimenopause can be observed as early as age 43 yr and include hyperestrogenism, hypergonadotropism, and decreased luteal phase progesterone excretion. These hormonal alterations may well be responsible for the increased gynecological morbidity that characterizes this period of life. 相似文献
4.
The consistent, but often wrong, impressions people form of the size of unseen speakers are not random but rather point to a consistent misattribution bias, one that the advertising, broadcasting, and entertainment industries also routinely exploit. The authors report 3 experiments examining the perceptual basis of this bias. The results indicate that, under controlled experimental conditions, listeners can make relative size distinctions between male speakers using reliable cues carried in voice formant frequencies (resonant frequencies, or timbre) but that this ability can be perturbed by discordant voice fundamental frequency (F?, or pitch) differences between speakers. The authors introduce 3 accounts for the perceptual pull that voice F? can exert on our routine (mis)attributions of speaker size and consider the role that voice F? plays in additional voice-based attributions that may or may not be reliable but that have clear size connotations. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
5.
This investigation examined the timing relationships of EMG activity underlying vowel production in 2 normal individuals and in 2 individuals with marked-to-severe apraxia of speech of approximately two-and-one-half years duration. The timing of lip muscle activity was investigated in monosyllabic words embedded in phrases and in syllable word stems as a function of changes in word length. Specifically, the onset and offset of EMG activity of lip muscles used for production of /u/ in the monosyllables and word stems were examined. The results revealed that the relative amounts of time devoted to onset and offset of EMG activity for lip rounding are disorganized in apraxia of speech. Word length appeared to affect the timing of the onset of muscle activity for both the normal speakers and the speakers with apraxia of speech. Word length also influenced the offset of muscle activity, but its effect was less systematic for the speakers with apraxia of speech. The findings suggest that termination of EMG activity may be at least as disturbed as the initiation of EMG activity in apraxia of speech. 相似文献
6.
OBJECTIVE: As disability is highly prevalent among older women, is costly, and affects the quality of life, preventable causes of disability must be identified. In this study, we investigated the relationship between the body mass index (BMI), weight change, and the onset of disability in older women. DESIGN: Prospective cohort study. SETTING: The nationally representative US epidemiologic follow-up study of the National Health and Nutrition Examination Survey (NHANES) I (1971 through 1987). PATIENTS: White women classified as young-old (mean age 60 years at baseline, mean age 65 years at follow-up) and old-old (mean age 76 years at baseline, mean age 80 years at follow-up). MAIN OUTCOME MEASURES: The relative odds for the onset of mobility disability associated with tertiles of past BMI (measured 8 to 16 years prior to disability ascertainment) and current BMI (measured 2 to 5 years prior to disability ascertainment) and with weight change between the two weight measurements. RESULTS: In both cohorts, women in the high past BMI group (> 27 in the young-old and > 28.1 in the old-old cohort) had a twofold increase in the risk for disability compared with women in the low past BMI group. High current BMI was as strongly related as past BMI to risk of disability in the young-old women; it was not as strong a predictor in old-old women. In the old-old group only, women who experienced a weight loss of more than 5% had a twofold increase in risk of disability compared with weight-stable women. These results were adjusted for age, smoking, education, and study time and were not importantly modified with the addition into the models of single or multiple health conditions. CONCLUSIONS: These prospective data suggest that high BMI is a strong predictor of long-term risk for mobility disability in older women and that this risk persists even to very old age. However, the paradoxical increase in risk associated with weight loss in the old-old women requires further study. Programs to prevent overweight may have potential for decreasing disability in women. 相似文献
7.
Tracheoesophageal (TE) speech is now the most common method of voice rehabilitation after total laryngectomy. The speech intelligibility of laryngectomees who use TE speech as their primary mode of communication was evaluated by 20 "naive" listeners. Two speech intelligibility tests were administered using phonetically balanced rhyming words or lists of spondee words. The overall intelligibility for the group of laryngectomees was 76%, with a wide range of variability among the individual TE speakers. We concluded that TE speech is significantly less intelligible to naive listeners than normal laryngeal speech; further refinement of voice rehabilitation for laryngectomees is needed. 相似文献
8.
The major aim of this study was to describe the conversational abilities of a group of severely injured TBI speakers, at a minimum of 2 years post-injury. The association between conversational impairment and (a) selected measures of executive function and (b) psychosocial handicap was also examined. Twenty-four members of the group of 26 severely injured TBI speakers who had initially been assessed between 3 and 6 months post-injury were reviewed at a minimum of 2 years post-injury (mean = 2 years, 10 months). At initial assessment, TBI speakers were compared with non-TBI orthopaedic patients and with a group of university students. At follow-up, however, they were compared only with the orthopaedic patients. Conversational assessment was carried out using a modified form of Damico's Clinical Discourse Analysis. As a group, the TBI speakers' conversational abilities did not improve over time. There was, however, a subgroup (n = 8) of speakers who did improve, and these could be distinguished by greater initial severity of injury and a significantly longer period of speech-language pathology intervention than the speakers who either remained the same or worsened over time. Modest associations between conversational discourse skills and measures of executive function and a measure of psychosocial handicap were identified. These findings indicate that disruptions in conversation persist into the longer term. More assiduous efforts may need to be made to (a) identify subtle discourse changes in the early months after injury and (b) engage TBI speakers in speech-language pathology services. Such services are also required over a longer time frame, in community-based models of service provision. 相似文献
9.
CM Sapienza 《Canadian Metallurgical Quarterly》1997,11(4):410-416
Laryngeal aerodynamic and acoustic characteristics of African American voice production were examined from vowel samples produced by ten adult female and ten adult male speakers. The data were compared with that for a control group consisting of ten adult female and ten adult male White speakers, matched for age, height, and weight. All measures were analyzed using Cspeech 4.0. Aerodynamic measurements, extracted from a glottal airflow waveform, included maximum flow declination rate, alternating glottal airflow, minimum glottal airflow, and airflow open quotient. Acoustic measures included fundamental frequency and sound pressure level. No significant mean differences between the African American and White speakers were found, except for maximum-flow declination rate. The White speakers produced significantly higher declination rates than the African American speakers. The factor of sex for the African American speakers was statistically significant for the measures of maximum-flow declination rate, alternating glottal airflow, open quotient, and fundamental frequency, consistent with the functioning of the White speakers. The results suggest that during vowel production, where the vocal tract is in a fairly static position, acoustic and aerodynamic characteristics for African American and White Speakers are comparable. 相似文献
10.
Examined speech addressed to different categories of listeners in a study in which 80 undergraduate women taught a block design task to either a 5–7 yr old girl (n?=?6), a retarded adult (4 women, aged 20–33 yrs), a peer who spoke English as a 2nd language (4 adult women [foreigners]), or a peer who was an unimpaired native speaker of English (2 women undergraduates). Speech addressed to children differed from the speech addressed to native adults along every major dimension. It was clearer, simpler, more attention maintaining, and included longer pauses. Speech addressed to retarded adults was similar to speech addressed to 6-yr-olds. Speech to the retarded adults did differ in timing from the other styles of speaking in that it included fewer and somewhat shorter pauses. Speech addressed to foreigners was more repetitive than speech addressed to native speakers, but in all other ways it was similar. Results show that speakers fine-tuned their communications to the level of cognitive and linguistic sophistication of their listener. The hypothesis that baby talk (the speech addressed to children) is a prototypical special speech register from which other special registers are derived is discussed. (66 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
11.
JT Green J Rhodes K Ragunath GA Thomas GT Williams V Mani C Feyerabend MA Russell 《Canadian Metallurgical Quarterly》1998,93(9):1463-1467
OBJECTIVES: Ulcerative colitis (UC) is largely a disease of nonsmokers. There are few patients who are current smokers, but we have identified a group and reviewed their clinical status, disease activity, and nicotine exposure to examine whether they remain well controlled while smoking. METHODS: Fifty-one patients from three centers with verified UC were reviewed. RESULTS: Thirty of the group were men; mean age 50 yr, with a mean age of onset of 37 yr. Twenty-two patients had proctosigmoid disease, 12 involvement of left colon, and 17 total colitis. All were current smokers; 41 were cigarette smokers averaging 17 daily. At the onset of colitis 30 were nonsmokers, 25 of them were ex-smokers and 19 developed colitis within 2 yr of stopping smoking. Twenty-eight believed smoking improved disease activity and none felt smoking had a detrimental effect on their UC. Eleven were receiving no medication for UC, 40 were receiving 5-ASA (5-aminosalicylic acid) preparations, and only two took oral steroids. All were in clinical remission, with the exception of one patient; mean St. Marks score was 1.5, out of a possible total of 22. Sigmoidoscopic grades were inactive in all patients except three. Histological assessment showed significant activity in only five. Median serum nicotine was 8 ng/ml (range, 0.4-24.4), median serum cotinine 180 ng/ml (range, 20-453), with corresponding salivary cotinine of 255 ng/ml (range, 34-683). Median rise in nicotine 2 min after a cigarette in 35 patients was 12.1 ng/ml (range, 0.4-44). CONCLUSIONS: Because most current smokers with UC have inactive disease, smoking may contribute to the clinical remission in these patients. 相似文献
12.
RL Gajdosik DW Faris TK Kato PF Roosa T Matsumoto 《Canadian Metallurgical Quarterly》1997,84(2):575-586
This study examined the ability to control leg velocities during concentric and eccentric actions of the right quadriceps muscles. Ten healthy women (M age = 25.9 +/- 3.5 yr.) were tested using the Isotonic Program of the KIN-COM II 500H dynamometer. They attempted to match velocity tracings of 10 degrees, 20 degrees, and 40 degrees/sec. through 70 degrees of knee range of motion at a load equal to 10% of their maximal mean concentric force. The actual mean velocities, mean percent deviation from the target velocities, and the coefficient of variation for both actions were calculated for 15 degrees-75 degrees (full range of motion), 15 degrees-45 degrees (shorter range of motion), and 46 degrees-75 degrees (longer range of motion). Separate one-way analyses of variance with two trial factors (action x velocity) showed faster concentric velocities through the full and longer ranges of motion, and faster eccentric velocities through the shorter range of motion. Mean percent deviations indicated that the eccentric velocities were generally more accurate within all ranges of motion. Larger concentric coefficients of variation were found within the full and longer ranges of motion, and the coefficients of variation for both actions decreased as the velocities increased. An exaggerated 'velocity overshoot' at the onset of both actions probably contributed to differences in the velocities and coefficients of variation. The results indicated differences between the concentric and eccentric actions, explained in part by the testing methodology used and by the known mechanical and physiological characteristics of the two muscle actions. 相似文献
13.
To account for cross-linguistic differences in agrammatism, Bates and her colleagues have employed the Competition Model, proposing that the cue validity and cue costs of a grammatical morpheme in a particular language will directly affect how agrammatism is manifested. Using Goodglass et al.'s (1993) Morphosyntax Battery in English and a translated version in Spanish, we analyzed the use of equivalent grammatical structures in production and comprehension by agrammatic speakers of the two languages. Wilcoxon signed-rank tests revealed that the relative order of difficulty in both production and comprehension of various grammatical morphemes was the same for both Spanish- and English-speaking agrammatic patients, with two exceptions (1) the Spanish-speaking agrammatics were relatively better at producing subject-verb agreement, and (2) the Spanish speakers were significantly worse at comprehending both active and passive voice sentences. The Competition Model can explain the performance differences regarding subject-verb agreement and comprehension of active voice sentences, but it cannot account for the differences seen in comprehending passive voice sentences. 相似文献
14.
Y Sakata 《Canadian Metallurgical Quarterly》1997,86(6):889-896
Prosthetic voice restoration has considerably improved the results of vocal rehabilitation after total laryngectomy, and is presently the method of choice for many health-care providers treating laryngectomized patients. The Provox voice prosthesis, developed in the Netherlands Cancer Institute, is an indwelling device that has been applied in recent years with regular success. Its retrograde replacement method, using a disposable guide wire, assures reliable, atraumatic positioning of the prosthesis in the tracheoesophageal fistula. However, the method sometimes may be uncomfortable for the patient; therefore an adapted prosthesis and new replacement equipment were developed, which enable bidirectional insertion, i.e. not only in the traditional retrograde manner through the pharynx, but especially in an anterograde manner through the stoma. This second-generation voice prosthesis (Provox 2) was studied in a prospective clinical trial in 44 patients (33 experienced patients, seven first-time replacements and four primary insertions). The study demonstrated that the anterograde insertion with the Provox 2 system was applicable in all patients, making the voice prosthesis even easier to handle than with the traditional retrograde method. A stenosis of the pharyngoesophageal segment no longer interfered with the replacement. In addition, the patients judged the new method as being favourable, reporting significantly less discomfort during the replacement procedure (paired Student's t-test: p < 0.0001). Furthermore, the adapted voice prosthesis could be removed from the tracheoesophageal fistula without excessive force (mean 7.9 N, range 6.0-14.0 N), more easily than the original Provox (mean 20.9 N, range 5.5-25.0 N). It can be concluded that this second-generation indwelling voice prosthesis (Provox 2) seems to be a further improvement in the application of this voice rehabilitation system, not only simplifying the replacement procedure, but also diminishing the discomfort for the patient. 相似文献
15.
BACKGROUND: Following total laryngectomy the voice is produced by esophageal speech as well as with voice prostheses by vibrations of pharyngeal mucosal folds. This pharyngeal sound normally has a significantly lower fundamental frequency than the healthy voice (men about 120 Hz, women about 240 Hz, pharyngeal voice about 70 Hz), which is a handicap especially for female laryngectomy patients. In order to improve the postlaryngectomy voice, a new type of voice prostheses containing an integrated sound-producing metallic reed element was developed (ADEVA Company, Lübeck, Germany). METHODS/PATIENTS: Thirty-five of these new sound-producing voice prostheses were tested in vitro for different prosthesis-specific physical parameters (pressure, flow, sound pressure, flow resistance, frequency range). In 15 voice prosthesis speakers, a sound-producing prosthesis was introduced during a routine outpatient visit. Besides measurement of the above mentioned physical parameters in patients with conventional and sound-producing prostheses, the resulting voice as also evaluated by means of a video recording. RESULTS: In vitro all prostheses with the metallic reed element produced a clear sound. Flow resistance of the prostheses was slightly elevated by the reed element. Insertion of the prostheses was hindered by the reed element. Period of uninterrupted sound production was prolonged after insertion of a sound-producing prosthesis and patients could speak on a lower pressure level, but the sound of the reed element was permanently distinguishable only in 6 of 15 patients. CONCLUSIONS: In principle a variation of the pharyngeal voice by means of a sound producing element, which is integrated into a voice prosthesis, is possible. The current design of the metallic reed element tested is not yet suitable for routine clinical use: 1. The reed element is too sensitive and is easily damaged during insertion, so the insertion device has to be improved. 2. The sound producing element is blocked by small amounts of tracheal secretions, so that this element should be replaceable separately without requiring removal of the silicone value (if possible by the patient himself). Prior to insertion of the sound producing voice prosthesis the maximum air flow through the shunt should be measured to determine if the patient can produce the necessary air flow for activation of the reed element. A further improvement for these special types of voice prostheses would be a sound producing element, which generates a variable frequency of sound. Limiting the patient to only one fundamental frequency creates a monotone, which does not sound naturally. Initial progress toward a sound-producing voice prostheses has been made. This should be followed by the necessary improvements in order to improve the feasibility of this design for routine clinical use. 相似文献
16.
Survival in patients with amyotrophic lateral sclerosis is highly variable. In a prospective study of 71 patients, we analyzed the influence of several clinical factors on survival: age of onset, sex, initial involvement (bulbar, upper extremities or lower extremities) and familial history. Mean time of evolution was 2.6 years, with 25% survival 5 years after onset. Patients under 45 years old had better survival than those over 45 (5.8 and 2.2 years, respectively, p < 0.002). The prognosis for women was worse (2.07 and 3.6 years for women and men, respectively, p < 0.001), probably because age of onset was later in women (61 versus 53 years, respectively, p < 0.006). Neither first symptom or familial history of the disease affected prognosis. We conclude that age at onset is a decisive prognostic factor that is inversely related to survival. In the design of clinical trials in which survival is a variable, the treatment and control groups should be matched for age. 相似文献
17.
AJ Parkinson WS Parkinson RS Tyler MW Lowder BJ Gantz 《Canadian Metallurgical Quarterly》1998,41(5):1073-1087
Sixteen experienced cochlear implant patients with a wide range of speech-perception abilities received the SPEAK processing strategy in the Nucleus Spectra-22 cochlear implant. Speech perception was assessed in quiet and in noise with SPEAK and with the patients' previous strategies (for most, Multipeak) at the study onset, as well as after using SPEAK for 6 months. Comparisons were made within and across the two test sessions to elucidate possible learning effects. Patients were also asked to rate the strategies on seven speech recognition and sound quality scales. After 6 months' experience with SPEAK, patients showed significantly improved mean performance on a range of speech recognition measures in quiet and noise. When mean subjective ratings were compared over time there were no significant differences noted between strategies. However, many individuals rated the SPEAK strategy better for two or more of the seven subjective measures. Ratings for "appreciation of music" and "quality of my own voice" in particular were generally higher for SPEAK. Improvements were realized by patients with a wide range of speech perception abilities, including those with little or no open-set speech recognition. 相似文献
18.
BACKGROUND: Chronic idiopathic intestinal pseudo-obstruction, a syndrome of ineffectual motility due to a primary disorder of enteric nerve or muscle, is rare. AIMS: To determine the clinical spectrum, underlying pathologies, response to treatments, and prognosis in a consecutive unselected group of patients. METHODS: Cross sectional study of all patients with clinical and radiological features of intestinal obstruction in the absence of organic obstruction, associated with dilated small intestine (with or without dilated large intestine), being actively managed in one tertiary referral centre at one time. RESULTS: Twenty patients (11 men and nine women, median age 43 years, range 22-67) fulfilled the diagnostic criteria. Median age at onset of symptoms was 17 years (range two weeks to 59 years). Two patients had an autosomally dominant inherited visceral myopathy. Major presenting symptoms were pain (80%), vomiting (75%), constipation (40%), and diarrhoea (20%). Eighteen patients required abdominal surgery, and a further patient had a full thickness rectal biopsy. The mean time interval from symptom onset to first operation was 5.8 years. Histology showed visceral myopathy in 13, visceral neuropathy in three, and was indeterminate in three. In the one other patient small bowel motility studies were suggestive of neuropathy. Two patients died within two years of symptom onset, one from generalised thrombosis and the other from an inflammatory myopathy. Of the remaining 18 patients, eight were nutritionally independent of supplements, two had gastrostomy or jejunostomy feeds, and eight were receiving home parenteral nutrition. Five patients were opiate dependent, only one patient had benefited from prokinetic drug therapy, and five patients required formal psychological intervention and support. CONCLUSIONS: In a referral setting visceral myopathy is the most common diagnosis in this heterogeneous syndrome, the course of the illness is usually prolonged, and prokinetic drug therapies are not usually helpful. Ongoing management problems include pain relief and nutritional support. 相似文献
19.
Examined the personality traits of speakers with different voice-quality profiles. Speech samples and MMPI scores were obtained from 78 male psychiatric patients. The speech samples were rated for the voice qualities of pitch, loudness, and tempo. Each S was assigned to 1 of 3 voice-quality profile groups: peak-pitch (N = 29), peak-loudness (N = 27), and peak-tempo (N = 22). An analysis of variance indicated a significant difference between the mean MMPI profiles of the 3 groups and supported the hypothesis that the 3 voice-quality profile groups represent 3 different personality types. (PsycINFO Database Record (c) 2010 APA, all rights reserved) 相似文献
20.
SD Chang RP Levy JR Adler DP Martin PR Krakovitz GK Steinberg 《Canadian Metallurgical Quarterly》1998,43(2):213-20; discussion 220-1
OBJECTIVE: Radiosurgery is generally effective in obliterating true arteriovenous malformations, but less is known about its effects on angiographically occult vascular malformations (AOVMs). Since July 1983, 57 patients with surgically inaccessible AOVMs of the brain were treated using helium ion (47 patients) or linear accelerator (10 patients) radiosurgery. This study retrospectively evaluates the response of these AOVMs to treatment. METHODS: All patients presented with previous hemorrhage. The mean patient age was 35.6 years (range, 13-71 yr). The mean AOVM volume was 2.25 cm3 (range, 0.080-15.2 cm3), treated with a mean of 18.0 Gy equivalent (physical dose x relative biological effectiveness, which is 1.3 for helium ion Bragg peak) (range, 7.0-40 Gy equivalent). The Drake scale scores before treatment were as follows: excellent (25 patients), good (26 patients), and poor (6 patients). The mean follow-up period was 7.5 years (range, 9 mo-13.8 yr). RESULTS: Eighteen patients (32%) bled symptomatically (20 hemorrhages) after radiosurgery. Sixteen hemorrhages occurred within 36 months after radiosurgery (9.4% annual bleed rate; 16 hemorrhages/171 patient yr); 4 hemorrhages occurred more than 36 months after treatment (1.6% annual bleed rate; 4 hemorrhages/257 patient yr) (P < 0.001). Complications included symptomatic radiation edema (four patients, 7%), necrosis (one patient, 2%), and increased seizure frequency (one patient, 2%). Eight patients underwent surgical resection of their AOVMs 8 to 59 months after radiosurgery because of subsequent hemorrhage. The Drake scale scores after treatment were as follows: excellent (25 patients), good (24 patients), poor (3 patients), and dead (5 patients, 3 of whom died as a result of causes unrelated to the AOVMs or radiosurgery). CONCLUSION: Radiosurgery may be useful for AOVMs located in surgically inaccessible regions of the brain. A significant decrease in bleed rate exists more than 3 years after treatment compared with the bleed rate within 3 years of treatment. Because current neuroradiological techniques are not able to image obliterative response in these slow-flow vascular lesions, longer term clinical follow-up is required. 相似文献