Search PubMed⌕ Search

Biomedical subjects

M E Fischer

Publications and source records attributed to M E Fischer.

At least 19 recordsLinked to original sources
PubMed1999

Gustatory function after third molar extraction.

OBJECTIVE: The purpose of this study was to determine the severity and time course of taste changes after extraction of all 4 third molars. STUDY DESIGN: Taste function in 17 patients was measured before third molar surgery and at 1 month and 6 months after surgery. Two tests were administered: a whole-mouth, above-threshold test in which subjects sipped, expectorated, and then rated the intensities and identified the taste qualities of various solutions, and a localized test in which subjects rated and identified solutions painted with cotton swabs on different oral sites. RESULTS: Intensity ratings for solutions in the whole-mouth test were reduced by approximately 14% for NaCl, citric acid, and quinine hydrochloride at 1 month after surgery and had not recovered by 6 months after surgery for citric acid (P<.02). The taste quality of NaCl was identified correctly less frequently after third molar extraction. Perceived taste intensity on discrete areas of the tongue was significantly reduced after surgery (P<.05). Patients with the most severely impacted molars gave the lowest taste intensity ratings to whole-mouth test solutions at 6 months after surgery (P<.02). In contrast, taste function in a group of subjects who received only local dental anesthesia was not affected. CONCLUSIONS: Gustatory deficits occur after third molar extraction, persist for as long as 6 months after surgery, and appear to be associated with depth of impaction.

Adolescent↗
PubMed1998

Perioperative outcomes of major hepatic resections under low central venous pressure anesthesia: blood loss, blood transfusion, and the risk of postoperative renal dysfunction.

BACKGROUND: We have previously demonstrated that maintenance of a low central venous pressure (LCVP) combined with extrahepatic control of venous outflow reduced the overall blood loss during major hepatic resections. This study examined the overall outcomes and, in particular, renal morbidity associated with a large series of consecutive major liver resections performed with this approach. In addition, the rationale for the anesthetic management to maintain LCVP was carefully reviewed. STUDY DESIGN: All major hepatectomies performed between December 1991 and April 1997 were reviewed. The prospective Hepatobiliary Surgical Service database was merged with the Memorial Hospital Laboratory and Blood Bank databases to yield the nature of the operation, blood loss, blood product transfusions, outcomes, and levels of preoperative, postoperative, and discharge serum creatinine and blood urea nitrogen. RESULTS: A total of 496 LCVP-assisted major liver resections were performed, with no intraoperative deaths and an in-hospital mortality rate of 3.8%. The median blood loss was 645 mL. Sixty-seven percent of the patients did not require perioperative blood transfusion during surgery and the immediate 12 hours after surgery. The median number of blood transfusions was 2. Only 3% of the patients experienced a persistent and clinically significant increase in serum creatinine possibly attributable to the anesthetic technique. Renal failure directly attributable to the anesthetic technique did not occur. CONCLUSIONS: Major resection with LCVP allowed easy control of the hepatic veins before and during parenchymal transection. The anesthetic technique, designed to maintain LCVP during the critical stages of hepatic resection, not only helped to minimize blood loss and mortality but also preserved renal function.

Blood Loss, Surgical↗
PubMed1997

The effects of endobronchial cuff inflation on double-lumen endobronchial tube movement after lateral decubitus positioning.

OBJECT: This study was designed to measure changes in tracheal and bronchial lumen distances from mainstem and secondary carina with lateral positioning, and to assess whether inflation of the endobronchial cuff before lateral positioning would further secure a double-lumen endobronchial tube (DLT) and reduce movement. DESIGN: Prospective study. SETTING: University-affiliated cancer center. PARTICIPANTS: Fifty adult patients scheduled for elective thoracic surgical procedures requiring the placement of a left DLT. INTERVENTIONS: Patients were sequentially assigned to either the endobronchial cuff-inflated group or the deflated group during lateral positioning. After induction of general anesthesia, a left polyvinylchloride (PVC) DLT was placed and the position confirmed. In the supine position, the distance from the tip of the tracheal lumen to main carina was measured using a fiberoptic bronchoscope (FOB) passed through the tracheal lumen, and the distance from the bronchial lumen to secondary carina was measured with the FOB passed through the bronchial lumen. The patients were then positioned laterally and a second set of measurements taken. Overall movement was determined by increases and decreases in tracheal and bronchial distances obtained by substracting supine values from lateral values. MEASUREMENTS AND MAIN RESULTS: There was significant tracheal movement in 40 of 50 patients, with a mean of 0.92 +/- 1.0 cm. This was predominantly in the upward direction, as seen in 35 of 50 patients. There was significant bronchial movement in 37 of 50 patients, with a mean of 0.92 +/- 1.15 cm. Also, predominance in the upward direction was seen in 34 of 50 patients. CONCLUSIONS: DLTs move with lateral positioning, regardless of endobronchial cuff inflation. The movement is predominantly in the upward direction. Therefore, fiberoptic visualization in the supine position should be used only to confirm that the endobronchial lumen is placed on the appropriate side and the cuff is at least 1 cm inside the left mainstem bronchus. Final positioning should always be verified in the lateral position.

Adult↗
PubMed1997

Preoperative pulmonary evaluation of the thoracic surgical patient.

A test designed to separate those undergoing thoracic surgery without complications and those with complications must be both highly specific and sensitive. Clearly, the difference between patients at opposite ends of the population curves is easy to identify. Spirometry can be helpful for screening, although it is not a very discriminating test. If patients fall in the overlap region between the populations, however, it is impossible to discern the risks with any certainty using low-yield tests. A test with higher sensitivity, specificity, and predictive values is necessary to ascertain such marginal differences. With this kind of analysis at hand, preoperative testing can be divided into three predictive value groups. Calculating the predictive value of each preoperative test can provide a comparative measure of usefulness of discriminative power (Table 1). In this way, spirometry, blood gas analysis, and stair climbing tolerance are shown to be poor predictors of outcome. An intermediate predictive value can be achieved using diffusion capacity, exercise-induced decreases in O2 saturation, and exercise PVR. High predictive value can be accomplished with combination indexes (PPP, possibly PRQ), measurement of VO2 at 40 watts of exercise, or VO2max. Logic dictates a step-wise preoperative evaluation using prediction value analysis (Fig.4). A flow decision chart for the preoperative evaluation of patients for pulmonary resection begins with exercise oximetry, spirometry, and blood gas analysis as general screening tests to separate those patients at minimal or no risks for complications from those patients that require further evaluation. Functional indexes (PPP, PRQ) or exercise testing can aid further in the selection of those patients in whom a nonsurgical option should be considered. Flow decision chart for the preoperative evaluation of patients for pulmonary resection should continue to evolve as new information about outcome studies is gathered. Examination of outcome data will provide us with reduction of the size of the nonoperable population, so that we can deny only those patients who truly pose a prohibitive risk.

Blood Gas Analysis↗
PubMed1993

Self-reported dietary changes with respect to American Cancer Society nutrition guidelines (1982-1986).

A follow-up study was conducted by the Illinois Division of the American Cancer Society (ACS) in conjunction with the ongoing National Cancer Prevention Study II (CPSII) to determine whether self-report dietary changes are occurring in accordance with the ACS nutrition guidelines and to identify demographic subgroups that may be targeted for future prevention and education programs. A total of 42,300 CPSII respondents completed a 1986 questionnaire and were matched to 1982 baseline data. Dietary items were recorded as "on the average, how many days per week do you eat the following foods?" Individuals with known chronic conditions, body mass index outside a moderate range, and fewer than four completed food items were excluded. The remaining study population (n = 18,062) included men and women who were apparently healthy and primarily over the age of 50. The distribution of foods reported in 1982 and changes in foods consumed (1982-1986) among selected food groups varied modestly by sex, age, and educational level. Modest changes in the direction of decreasing intake of high-fat foods and increasing intake of high-fiber foods and cruciferous vegetables were reported. Dietary changes consistent with the ACS nutrition guidelines appear to have taken place in this population, particularly for the use of fried foods in males and intake of high-fiber foods and cruciferous vegetables in females.

Adult↗
PubMed1993

Focal hyperintensities in cerebral white matter on MR images of asymptomatic volunteers: correlation with social and medical histories.

OBJECTIVE: Previous attempts to explain the presence of focal hyperintensities in the cerebral white matter on MR images have focused on the patient's age and cardiovascular risk factors. The purpose of this study was to survey many variables in subjects' social, medical, and surgical histories to identify those factors associated with focal hyperintensities in asymptomatic persons. SUBJECTS AND METHODS: Asymptomatic volunteers were examined with MR imaging of the head and questioned concerning smoking history; chemical dependence; alcohol consumption; medical history (e.g., high blood pressure, kidney disease); surgical history (e.g., for appendix, gallbladder); medications (e.g., antihypertensives, analgesics); and other historical family and social variables. Vital signs were recorded. Focal hyperintensities were counted by observers who were not provided any information about the subjects other than that they were either volunteers or patients. Each of the variables in the history was tested for an association with the number of focal hyperintensities seen on MR images. RESULTS: A statistically significant positive association was found between both age and the use of antihypertensive medications and the number of focal hyperintensities. Associations were also found between the number of focal hyperintensities and diastolic and systolic blood pressures at the time of MR imaging, but these associations did not reach statistical significance. No other variables in the medical, surgical, or social histories were found to be significantly related to the number of focal hyperintensities. CONCLUSION: Age and the use of antihypertensive medications were the only significant risk factors identified in respect to focal hyperintensities of the cerebral white matter.

Adult↗
PubMed1992

Quantitative MR in the diagnosis of multiple sclerosis.

In patients with multiple sclerosis (MS), the apparently uninvolved cerebral white matter between demyelinated plaques may have biochemical abnormalities. To what degree the changes in the white matter contribute to symptomatology in MS is unknown. In 39 patients with multiple sclerosis, and in 39 age-matched nondiseased volunteers, T1 and T2 were calculated from spin-echo images in four regions of apparently uninvolved white matter. In three of four white matter areas, the average T1 and T2 were significantly longer in the patients than in the controls. The T1 correlated with the disability, measured by the Kurtzke Extended Disability Status Scale, although the correlation was marginally significant. The results suggest that in patients with MS, white matter disease that is not visualized in MR as distinct foci of abnormal signal intensity may contribute to disease burden and disability.

Brain↗
PubMed1992

High-signal foci on MR images of the brain: observer variability in their quantification.

Foci of high signal in the cerebral white matter are common incidental findings on MR images of the brain of control subjects or patients with a variety of diseases. Although the number of foci has been reported to correlate with age and several risk factors, the degree of observer variability in quantifying foci has not been reported. We used kappa statistics to determine radiologists' agreement in counting high-signal-intensity foci on MR images obtained in healthy volunteers and in patients with hypertension. Before interpreting the images, one pair of radiologists studied 30 routine MR images and reached consensus on differentiating high-signal foci from other foci of high intensity caused by normal structures (e.g., deep gyri or Virchow-Robin spaces). These two observers than independently determined the number of foci in the study group. Using their own criteria, other radiologists independently counted the foci. Agreement between observers was determined with the kappa statistic. The results showed fair agreement between the radiologists who first reached a consensus in counting foci of hyperintensity and poor agreement between the other observers. We conclude that in order to compare the frequency of foci of hyperintensity in different groups of patients, observer variability must be controlled. Studies without proper control subjects may lead to incorrect conclusions regarding the correlation of focal hyperintensities and various risk factors.

Alzheimer Disease↗
PubMed1991

Multiple sclerosis: specificity of MR for diagnosis.

The specificity of magnetic resonance (MR) imaging in the diagnosis of multiple sclerosis (MS) has not been measured systematically. Conventional MR head images with sagittal localizer and axial multiple-echo sequences with long repetition times were obtained in 92 patients with clinically verified MS (Schumacher criteria), 100 healthy volunteers, 60 subjects with hypertension, and eight patients with dementia. Two readers, without the aid of any clinical or demographic information, classified each of the 260 studies as MS or not MS. The readers classified the studies again after being supplied with the subjects' ages and sex. True-negative and true-positive diagnoses of MS were tabulated. The specificity of the MR diagnosis of MS (true-negative results in proportion to all non-MS studies) was 95%-99% with all the control groups included. There is a small risk of misinterpreting incidental periventricular white matter foci as plaques of MS in MR studies.

Adult↗
PubMed1991

T1 and T2 in the cerebrum: correlation with age, gender, and demographic factors.

The authors measured the T1 and T2 of cerebral tissue in 164 volunteers aged 5-90 years and correlated T1 and T2 with age, gender, and various demographic variables. A weak correlation with statistical significance was found between age and T1 and T2 in white and gray matter structures. The T1 and T2 in the telencephalon increased by about 0.1% per year. No correlation of T1 or T2 with any other demographic, life-style, or medical factors was found.

Adolescent↗
PubMed1990

Intervertebral disk: normal age-related changes in MR signal intensity.

The effect of age on the signal intensity of normal lumbar intervertebral disks was studied. Twenty-seven cadavers ranging in age from newborn to 79 years were studied with use of a 1.5-T magnetic resonance (MR) imager within 48 hours of death. The signal intensity in the central area of the disk was measured on a sagittal image obtained with a long repetition time (TR) and a long echo time (TE) and correlated to the age. A significant correlation between the decrease in signal intensity and age was found, although signal intensity changed less than 6% in 80 years. The decrease in signal intensity is concomitant with decreases in water and glycosaminoglycans and increases in collagen in the disk.

Adolescent↗
PubMed1989

T1 and T2 measurements on a 1.5-T commercial MR imager.

In order for relaxation times to be used in clinical diagnosis, the precision of the measurement must be determined. The authors measured T1, T2, and proton density in a phantom and in human volunteers to determine the reproducibility of the method. The coefficient of variance of T1 measurements in the phantom during a 15-month period with two software upgrades was 5%. Variance of T2 measurements with any given software was 4% or less, and overall in the 15-month period, with two software changes, the T2 reproducibility was between 6% and 9%. The reproducibility is sufficiently high that precise clinical measurements of T1, T2, and proton density are feasible.

Adult↗
PubMed1988

Cardiac rehabilitation after myocardial infarction. Combined experience of randomized clinical trials.

Randomized clinical trials of cardiac rehabilitation following myocardial infarction have typically demonstrated a lower mortality in treated patients, but with a statistically significant reduction in only one trial. To overcome the problem of not being able to detect small but clinically important benefits in mortality in randomized clinical trials of exercise and risk factor rehabilitation after myocardial infarction with small numbers of patients, we carried out a meta-analysis on the combined results of ten randomized clinical trials that included 4347 patients (control, 2145 patients; rehabilitation, 2202 patients). The pooled odds ratios of 0.76 (95% confidence intervals, 0.63 to 0.92) for all-cause death and of 0.75 (95% confidence intervals, 0.62 to 0.93) for cardiovascular death were significantly lower in the rehabilitation group than in the control group, with no significant difference for nonfatal recurrent myocardial infarction. These results suggest that, for appropriately selected patients, comprehensive cardiac rehabilitation has a beneficial effect on mortality but not on nonfatal recurrent myocardial infarction.

Aged↗
PubMed1988

A weight shape index for assessing risk of disease in 44,820 women.

The medical literature gives ample evidence of the relationship between obesity and specific diseases such as adult-onset diabetes and hypertension. Until recently the sole focus of the relationship has been between morbidity and the degree of overweight which is usually measured as weight relative to height. Recently we have shown that the location of body fat is not only associated with morbidity but that this relationship is independent of the total amount of adipose tissue. Clinical studies have shown that adipocyte size, location and metabolism are related to fat distribution. An excess of large fat cells in the upper body explains the increase risk of diabetes in women. The location of body fat has been used to delineate three body types: gynoid (pear shape), intermediate, and android (apple shape). We used waist girth divided by hip girth for scaling body shape and found that it is associated with morbidity after adjustment for relative weight. The use of relative weight and body shape simultaneously gives a better estimate of risk of morbidity than either alone. This study of 44,820 women presents easy to read graphs, derived from the multiple logistic model, which will permit practicing physicians to estimate visually the combined risks associated with relative weight and body fat location.

Adipose Tissue↗
PubMed1986

The association of obesity with joint pain and osteoarthritis in the HANES data.

Data from 4225 persons from the National Health and Nutrition Examination Survey (HANES) was used to determine whether obesity was associated with osteoarthritis (OA) or joint pain. Subjects were divided into four groups on the basis of sex and race. We found that obesity was associated with OA of the knee for each sex/race group (p less than 0.01). The association was strongest for women, and it was present even for subjects without evidence of knee pain on physical examination. Frame size was not significantly associated with OA of the knee. Relative weight was weakly associated with OA of the hips in white women and nonwhite men but not significantly associated with OA of the sacroiliac joint. Diabetes did not seem to be an important risk factor for OA. These results suggest that the additional mechanical stress resulting from obesity is the principal reason for the association between obesity and OA.

Adult↗
PubMed1984

Silicone devices for tubal occlusion: radiographic description and evaluation.

Hysteroscopically placed silicone devices for occlusion of fallopian tubes have been evaluated in over 1,300 patients as a means of contraception during the past five years. Radiologic evaluation of the device is vital to the gynecologist both at initial implantation and for follow-up. Normal appearance of plugs and typical examples of complications including separation, extravasation, and abnormal configurations, are presented.

Contraceptive Devices, Female↗