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PubMed1983

Postural displacements of the brain--on the feasibility of using CT for determination of stereotactic coordinates.

Ten patients were studied with CT. In order to achieve consistent and reproducible CT slices an external helmet fixation system was used. Certain well defined cerebral structures were chosen as anatomical landmarks and their relationship to the skull determined with the patient in supine, lateral and prone positions. No displacements of brain structures could be observed. The results show the feasibility of using the same coordinates for intracranial structures at CT and at operation irrespective of the position of the patient's head at these procedures. Four of these patients were examined after lumbar intrathecal administration of 5 ml metrizamide (200 mgJ/ml). This small amount of positive contrast does not seem to influence on the position for the brain.

Brain↗

PubMed1980

Influence of posture on hepatic blood flow.

Hepatic blood flow was measured in 28 patients in supine and prone positions using the 133Xe-inhalation washout method. Even though the reactions in individual patients were considerably different, a mean blood flow of 60.9 ml/100 g/min was unaltered in both positions. This constancy of hepatic blood flow values is valid for patients without liver disease, with chronic hepatitis, and with liver cirrhosis.

Chronic Disease↗

PubMed1987

Electromyographic evaluation of back muscle fatigue with repeated sustained contractions of different strengths.

The aim of the study was to obtain information on changes in surface electromyograms from the lumbar erector spinae muscles during fatiguing isometric contractions. Four male subjects held different target extension forces to fatique in a prone position under carefully controlled biomechanical conditions. Standard deviations of the distribution of EMG amplitudes (RMS values), autoregressive (AR) time series models of the 15th order and spectral densities were computed. At lower force levels, i.e., at about 50 to 100 Nm or 20-40% of estimated maximum voluntary contraction force (MVC), RMS values significantly decreased over time; at the highest level examined (on average 162 Nm), they increased. Over all force levels, the explained variances of AR models increased and mean power frequencies (MPF) decreased with increasing force. The first and second AR coefficients also exhibited significant changes, depending on both contraction time and strength. The AR time series structure of EMGs during short isometric test contractions at the lowest force level within 30 s after the failure point clearly indicated muscle fatigue and some differences remained in their dependence on the preceding force. The results suggest a concept of 'selective fatigue', and provide a basis for refined electromyographic evaluation of back muscle fatigue. Such an evaluation has to consider the force history preceding the failure point, or serious errors become unavoidable. The increase in RMS values does not constitute a criterion of back muscle fatigue at low force levels. AR time series models are recommended for the description of fatigue-induced electromyographic changes.

Adult↗

PubMed1993

Techniques for percutaneous renal biopsies.

The technique of renal biopsy includes the preparation of the patient, the localization of the kidneys, the biopsy itself and the postbiopsy care of the patient. A review of the literature and a survey of pediatric nephrologists practicing in the New York metropolitan area and in Philadelphia was used to determine what those techniques were. In preparation for biopsy, bleeding disorders are excluded and corrected if present. In units that localize the kidney by anatomical landmarks, a sonogram is performed at some earlier time to determine that the patient has two kidneys in the usual location. After sedation, patients are placed in the prone position, with a bolster under the abdomen. Sonography is the most commonly used localization method. This is followed by probing to confirm localization and depth. The Tru-Cut needle and the Franklin Vim Silverman needles are the two most commonly used. All nephrologists in the New York area then have the specimen examined to ensure adequacy of sampling. Postbiopsy care includes observation of vital signs, bed rest overnight and some limitation of activity for 2 days to 2 weeks subsequently. In the biopsy of renal allografts, palpation achieves adequate localization. The technique is otherwise the same as for the biopsy of native kidneys.

Biopsy, Needle↗

PubMed1996

Scintimammography with technetium-99m methoxyisobutylisonitrile: comparison with mammography and magnetic resonance imaging.

The aim of the study was to compare the diagnostic accuracy of scintimammography with technetium-99m methoxyisobutylisonitrile (MIBI; SMM) in the detection of primary breast cancer with that of mammography (MM) and magnetic resonance imaging (MRI). Fifty-six patients with suspected lesions detected by palpation or MM were included in the study. Within the 4 weeks preceding excisional biopsy, MM and MRI were performed in all patients. Between 5 and 10 min after the injection of 740 MBq 99mTc-MIBI, SMM in the prone position was performed. In the total group of 56 patients, 43 lesions were palpable, while 13 were non-palpable but were detected by MM. Breast cancer was confirmed by histopathology in 27 of the patients (22 palpable and 5 non-palpable carcinomas). The tumour size ranged from 6 to 80 mm in diameter. For non-palpable lesions, the sensitivity of SMM, MM and MRI was 60%, 60% and 100%, respectively, while the specificity was 75%, 25% and 50%, respectively. For palpable breast lesions, all methods showed high sensitivity (SMM 91%, MM 95%, MRI 91%) but SMM demonstrated significantly higher specificity (SMM 62%, MM 10%, MRI 15%). In two mammographically negative tumours (dense tissue), SMM showed a positive result. In comparison to MRI, one additional carcinoma could be diagnosed by SMM. It may be concluded that for palpable breast lesions, the diagnostic accuracy of SMM is superior to that of MM and MRI. Through the complementary use of SMM it is possible to increase the sensitivity for the detection of breast cancer and multicentric disease. In patients in whom the status of a palpable breast mass remains unclear, SMM may help to reduce the amount of unnecessary biopsies.

Biopsy↗

PubMed1997

Comparison of fluorine-18 fluorodeoxyglucose positron emission tomography and technetium-99m methoxyisobutylisonitrile scintimammography in the detection of breast tumours.

The aim of this study was to compare, in breast cancer patients, the diagnostic accuracy of positron emission tomography (PET) using fluorine-18 fluorodeoxyglucose (FDG) and scintimammography (SMM) using technetium-99m methoxyisobutylisonitrile (MIBI). A total of 20 patients (40 breasts with 22 lesions) were evaluated serially with MIBI and, on the following day, with FDG. For SMM, planar and single-photon emission tomography imaging in the prone position was performed starting at 10 min following the injection of MIBI (740 MBq). For PET, scans were acquired 45-60 min after the injection of FDG (370 MBq) and attentuation correction was performed following transmission scans. Results from SMM and PET were subsequently compared with the histopathology results. True-positive results were obtained in 12/13 primary breast cancers (mean diameter=29 mm, range 8-53 mm) with both FDG and MIBI. False-negative results were obtained in two local recurrences (diameter <9 mm) with both FDG and MIBI. In benign disease, FDG and MIBI did not localize three fibrocystic lesions, two fibroadenomas and one inflammatory lesion (true-negative), but both localized one fibroadenoma (false-positive). Collectively, the results demonstrate a sensitivity of 92%, and a specificity of 86%, for primary breast cancer regardless of whether FDG or MIBI was used. In contrast to MIBI scintigraphy, FDG PET scored the axillae correctly as either positive (metastatic disease) or negative (no axillary disease) in all 12 patients. The tumour/non-tumour ratio for MIBI was 1.97 (range 1.43-3.1). The mean standard uptake value (SUV) for FDG uptake was 2.57 (range 0.3-6.2). The diagnostic accuracy of SMM was equivalent to that of FDG PET for the detection of primary breast cancer. For the detection of in situ lymph node metastases of the axilla, FDG seems to be more sensitive than 99mTc-MIBI.

Axilla↗

PubMed1995

Infections of the upper respiratory tract in cases of sudden infant death.

The nasal cavities were examined in 56 cases of sudden infant death syndrome (SIDS) and 26 control cases and the following criteria were compared: inflammatory infiltration of the nasal mucosa (SIDS 59%--controls 65%; P = 0.577), diapedesis of inflammatory cells (SIDS 38%--controls 42%; P = 0.678), epithelial desquamation (SIDS 62%--controls 85%; P = 0.043); hyperemia (SIDS 66%--controls 65%; P = 0.951) and hypersecretion of the seromucous glands (SIDS 55%--controls 69%; P = 0.233). Only epithelial desquamation was found significantly more often in the controls than in SIDS cases, but these alterations are unspecific and are influenced by the postmortem interval. The intensity of rhinitis was not different between the SIDS and control groups. The frequency of rhinitis is therefore not specific for the sudden infant death syndrome, and seems to be merely a result of the high incidence of upper respiratory tract infections in this age group. We speculate, however, that infections of the nose in conjunction with other factors, such as prone position, covering of the head, hyperthermia, parental smoking and immaturity of the central nervous system, could play a role in the pathogenesis of the sudden infant death syndrome.

Autopsy↗

PubMed1992

Treatment of tumours of the pineal region and posterior part of the third ventricle.

The evaluation of tumours located in the posterior part of the third ventricle or pineal region is achieved best by magnet resonance imaging (MRI). It shows the exact localization and extent, the involvement of neighbouring structures like thalamus or quadrigeminal plate and the displacement of the large veins, the internal cerebral veins, the vein of Galen and the veins of Rosenthal. If only CT is available, angiography should be performed prior to operation to identify the course of the veins. In children with a pineal region tumour the "tumour markers" AFP and beta-HCG should be determined before operation. We approach the rare tumours entirely located within the posterior part of the third ventricle by the posterior interhemispheric transcallosal route with the patient in prone position with the head elevated. The same approach is used for pineal region tumours extending above the internal cerebral veins. Tumours arising from the posterior thalamus extending into the thalamus and ventricle as well, are better approached by the posterior transcortical transventricular route since the lateral view is rather limited by the midline approach. The most frequent tumours in the pineal region are approached if they are located below the internal veins by the infratentorial, supracerebellar route in the sitting position. A total of 60 cases are evaluated. If AFP and/or beta-HCG are positive a highly malignant nongerminomatous germ-cell tumour must be suspected. We recommend initial chemotherapy with a combination of Vinblastine, Ifosfamide and Cis-platin without biopsy to avoid tumour seeding. After the "markers" are normalized operative removal of the residual tumour and radiotherapy should be carried out. In a series of 13 children operated on for pineal region tumours a rigid neuropsychological and endocrine evaluation was performed with encouraging results. During the last 10 years we have performed 49 open operations and 11 stereotactic biopsies. 40% of the patients were children under the age of 18. 40% of the tumours in childhood and 60% in adults were benign. In childhood 24% were germinomas and 20% non-germinomatous germ cell tumours.

Adult↗

PubMed1996

Inhalation of prostacyclin (PGI2) for 8 hours does not produce signs of acute pulmonary toxicity in healthy lambs.

OBJECTIVE: To study the potential side effects and toxicity of inhaling prostacyclin (PGI2) aerosol for 8 h. DESIGN: In a prospective, randomized study 14 healthy lambs received either PGI2 (n = 7) or 0.9% NaCl (n = 7) as an aerosol for 8 h. SETTING: Institute for Surgical Research of the Ludwig-Maximilians-University of Munich. INTERVENTIONS: All animals were studied under general anesthesia in a prone position. They were first intubated endotracheally and later tracheotomized. PGI2 solution (median dose 28 ng/kg per min) or 0.9% NaCl was administered with a jet nebulizer (delivery rate 4-10 ml/h; mass median diameter of aerosol particles 3.1 microns). Bronchoalveolar lavage was performed before and after the inhalation period to collect epithelial lining fluid of alveoli. MEASUREMENTS AND RESULTS: Hemodynamic and respiratory parameters, systemic resorption (plasma levels of 6-keto-prostaglandin-F 1 alpha), in vitro bleeding time, collagen-induced platelet aggregation and global biochemical and cellular composition of the epithelial lining fluid were examined in order to assess the side effects and signs of acute pulmonary toxicity induced by inhaled PGI2. No statistically significant differences were found between the PGI2 and the control groups for any of the parameters examined. CONCLUSION: Inhalation of PGI2 (28 ng/kg per min) over a period of 8 h in healthy lambs does not produce major side effects or acute pulmonary toxicity.

Acute Disease↗

PubMed1982

Sitting or prone? Another argument for the latter.

The case is described of a one-year-old child who underwent a craniectomy in the prone position for the removal of an ependymoma of the cerebellar vermis which had invaded the fourth ventricle. Circulatory arrest occurred. External cardiac massage was successfully carried out without any change of position, and the operation was satisfactorily completed. It is suggested that such an outcome would have been less likely had the patient been in the sitting position. The value of capnography as a guide to the adequacy of the circulation is emphasized and illustrated.

Blood Circulation↗

PubMed1989

Practical co-table for direct coronal CT scanning.

Direct coronal CT scanning can be efficiently performed by a new co-table equipment, which requires a comfortable prone positioning of the patient, whereby the patient must only extend his head slightly. The co-table-unit is linked to the original CT table board directly within a few minutes, coming through the opening of the gantry from the rear. This practical co-table method serves to reduce motion artifacts and to improve image quality significantly. By this method coronal follow-up CT scans are exactly reproducable.

Humans↗

PubMed1991

Small bowel perforation during enteroclysis.

Small bowel perforation with massive intraperitoneal leakage of barium occurred during the performance of enteroclysis in a 72-year-old woman. It is postulated that an ischemic segment of the partially obstructed ileum had ruptured because of rapid intraluminal flow of contrast material and increased abdominal pressure when the patient was rotated to a prone position.

Aged↗

PubMedDate not supplied

[The pulse-respiratory quotient of persons with stable and instable postural circulation while standing (author's transl)].

The pulse-respiratory quotient of patients with postural circulatory instability is the same in a prone position as that of patients with stable postural circulation, however, it is higher in an upright postiion. This is not only caused by the higher pulse frequency of postural circulatory instable patients while standing, but also by the lower respiratory rate. The difference of the pulse-respiratory quotient between standing and lying indicates with more accuracy the diagnosis of postural circulatory instability. The severity of the symptoms is related not only to the pulse and respiratory rate, but also to the pulse-respiratory quotient. Tachycardiac patients with a high pulse-respiratory quotient show clinically symptoms more severe than tachycardiac patients with lower pulse-respiratory quotients. Due to the results shown here, the terms of rhythmical concordance and discordance are proposed.

Adolescent↗

PubMedDate not supplied

Pulmonary circulation in the reindeer.

Right heart catheterizations were performed in 56 sessions on 25 reindeer with determinations of blood pressure and oxygen saturation. Cardiac output was calculated from cineangiocardiograms. When the animals were placed in prone position, heart rate was about 50/min, mixed venous blood oxygen saturation 68 to 72%, right ventricular systolic pressure 27 mmHg, pulmonary arterial pressure 25/16/11 mmHg, pulmonary arterial wedge pressure 6--8 mmHg and pulmonary transfer time 4 to 5 cardiac cycles. When the animals were placed on their side, the heart rate rose to 90 b/min, mixed venous blood oxygen saturation decreased by about 4% and the right ventricular and pulmonary arterial pressures increased by about 10 mmHg; pulmonary arterial wedge pressure did not change. Hypoxemia led to an increase in heart rate, cardiac output and pulmonary arterial pressure; the latter two measures tended to increase whenever the heart rate increased. Under the conditions stated here, an increased pulmonary vascular resistance was calculated when pulmonary arterial pressure was increased.

Angiocardiography↗

PubMed1986

Surgical treatment of retinal detachment from macular hole.

Six cases of retinal detachment from the macular hole were treated by a procedure including closed vitrectomy, air-fluid exchange, and prone positioning of the patient. All of these detachments were of the idiopathic type. Five patients had myopia ranging from -13 to -20 diopters; one was emmetropic. The initial success rate can be considered 100%: in all six cases the retina remained attached during follow-up periods ranging from 4-10 months at least. One later recurrence was not caused by the macular hole. This new technique, which allows permanent releasing of vitreous traction and temporary closure of the hole, shows that idiopathic retinal detachment is caused by vitreous traction.

Aged↗

PubMed2001

Abdominosacral resection for primary irresectable and locally recurrent rectal cancer.

PURPOSE: The purpose of this study was to present a technique of abdominosacral resection and its results in patients with locally advanced primary or locally recurrent rectal cancer with dorsolateral fixation. METHODS: Between 1994 and 1999, 13 patients with locally advanced primary rectal cancer and 37 patients with locally recurrent rectal cancer underwent abdominosacral resection as part of a multimodality treatment, i.e., preoperative irradiation, surgery, and intraoperative irradiation. After the abdominal phase, the patient was turned from supine to prone position to perform the transsacral phase of the resection. RESULTS: Margins were microscopically negative in 26 patients (52 percent), microscopically positive in 18 (36 percent), and positive with gross residual disease in 6 patients. Operation time ranged from 210 to 590 (median, 390) minutes, and blood loss ranged from 400 to 10,000 (median, 3,500) ml. No operative or hospital deaths occurred. Postoperative complications occurred in 41 patients (82 percent); most notable were perineal wound infections or dehiscence (n = 24, 48 percent). Other complications were postoperative urinary retention or incontinence (n = 9, 18 percent), peritonitis (n = 4), grade II neuropathy (n = 1), and fistula formation (n = 3). Kaplan-Meier 3-year overall survival, disease-free survival, and local control rates were, respectively, 41 percent, 31 percent, and 61 percent. Completeness of the resection (negative vs. positive margins) was a significant factor influencing survival (P = 0.04), disease-free survival (P = 0.0006), and local control (P = 0.0002). CONCLUSION: The abdominosacral resection provides wide access and may be the therapeutic solution for the accomplishment of a radical resection for distally situated, dorsally or dorsolaterally fixed primary or locally recurrent rectal cancers.

Abdomen↗

PubMed2001

New, simple, ultrasound-guided infiltration of the pudendal nerve: topographic basics.

PURPOSE: We report the topographic relationship of the pudendal nerve to the accompanying pudendal vessels and the ischial spine and provide the basics for an ultrasonographic depiction of these structures. METHODS: Twenty-nine female and 29 male adult human cadavers were positioned prone to expose the deep gluteal region. In 58 left and 58 right pelves the course of the pudendal nerve and vessels at the ischial spine were evaluated and analyzed statistically (n = 116). RESULTS: Multitrunked pudendal nerves were found in 40.5 percent with a left-vs.-right ratio of 1:1.5. The diameters of the single-trunked nerves ranged from 1.3 to 6.8 (mean 3.6 +/- 1.1) mm. In 75.9 percent the pudendal nerve was found medial to the accompanying internal pudendal artery. The distance to the artery ranged from 17.2 mm medial to 8 mm lateral (mean, 3.4 mm medial +/- 4.1 mm). The distance to the tip of the ischial spine ranged from 13.4 mm medial to 7.4 mm lateral (mean, 2.1 mm medial +/- 3.7 mm). CONCLUSIONS: The knowledge of the close spatial relationship between the pudendal nerve and the internal pudendal artery is important for any infiltration technique and even surgical release. It demands real-time, visually controlled infiltration techniques, such as with ultrasound.

Aged↗

PubMed2001

New, simple, ultrasound-guided infiltration of the pudendal nerve: ultrasonographic technique.

PURPOSE: Anesthetic infiltration of the pudendal nerve at the ischial spine can relieve perineal pain in cases of compression or distention. The aim of our study was to look for a real-time, visually controlled infiltration technique using ultrasound. METHODS: Fifty-three volunteers were examined in a prone position using a 3.5-MHz curved-array probe in color-coded Doppler mode. The deep gluteal region was scanned in two perpendicular planes, longitudinal and transverse to the internal pudendal artery. RESULTS: On the transverse planes the ischial spine, the sacrospinous ligament, and the internal pudendal artery were depicted in all but two cases. In 47.2 percent of the cases one trunk of the pudendal nerve was detected directly. Nerves consisting of more than one trunk were not found. The thickness of the nerve ranged between 3.5 and 7 mm. CONCLUSIONS: In almost one-half of the cases a direct ultrasound-guided infiltration of the pudendal nerve is possible. In the remaining cases the nerve can be detected and blocked indirectly, using the ischial spine or the internal pudendal artery as a landmark.

Adolescent↗