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Obese paraplegics can suffer discomfort when they lie in a prone position and site in wheelchairs. Two paraplegic cases who underwent abdominoplasty to eliminate such complaints are presented, with satisfactory results.
To explore the possibility that gallbladder stone fragments might be able to be safely dissolved using methyl tert-butyl ether immediately after extracorporeal shock-wave lithotripsy (ESWL), a feasibility study in 8 patients with one to four partially calcified gallbladder stones was performed. The gallstones averaged 2.2 cm in diameter (range 1.3-3 cm) and contained layered or diffuse calcium detectable by computed tomography scan only (7 patients) or plain film (1 patient). After a 5F (1.7 mm) pigtail catheter was placed percutaneously into the gallbladder, ESWL fragmentation was performed using a renal stone lithotriptor. The patients were under general anesthesia and in the prone position on a support gantry designed for gallbladder stone ESWL. Following ESWL, methyl tert-butyl ether was infused and aspirated via the gallbladder catheter until no further stone material was radiologically detectable or could be dissolved. After 8-26 h (mean = 13 h) of methyl tert-butyl ether therapy, no radiologically detectable gallstones remained in 6 of 8 patients. Shell fragments of three peripherally calcified stones in 1 patient and the densely calcified, predominantly pigment stone in a second patient were refractory to combined therapy. Both ESWL and treatment with methyl tert-butyl ether were well tolerated in all patients, although bile leakage after catheter removal occurred in 3 patients, one of whom was treated by cholecystectomy. Additional measures to prevent bile leakage may be advisable if these two modalities are to be used in tandem. We found no evidence, however, that predissolution stone fragmentation with ESWL predisposed the gallbladder to either mucosal damage by methyl tert-butyl ether or increased absorption of it.
Clinically undetectable venous gas emboli (VGE) can be routinely demonstrated in both animals and men undergoing clinically uneventful decompression from hyperbaric environments. The effect of VGE on gas exchange and pulmonary hemodynamics in this setting is unclear. We therefore have studied the cardiopulmonary effects of clinically uneventful decompression on unanesthetized sheep. Sheep were instrumented with a femoral arterial catheter, Swan-Ganz catheter, chronic tracheostomy, and were loosely restrained in the prone position. Following baseline measurements of pulmonary artery pressure (pPA), mean pulmonary artery wedge pressure (pPAw), cardiac output (CO), arterial and mixed venous blood gases, Doppler ultrasonic bubble detection, and V/Q scans using 133Xe, the animals were exposed to: (a) a 15-min exposure to 6.03 ATA (n = 8), (b) a 17.5-min exposure to 6.03 ATA, or (c) a 15-min control period at 1 ATA (n = 7). All measured parameters remained unchanged in the control group. VGE were detected in all animals exposed to pressure. In both exposure groups CO fell 20% (P < 0.05) and pulmonary vascular resistance (PVR) rose 60% (P < 0.05) compared to the control group. This rise in PVR was significantly in excess of that predicted for the observed fall in CO. Analysis of pPA and pPAw suggested neither right nor left ventricular failure. No significant abnormalities of gas exchange were detected. V/Q scans remained unchanged in all animals. We conclude that CO and PVR are altered by clinically uneventful decompression stress.
This study was done to determine whether minimally invasive endourologic management of calculi in continent reservoirs can be done effectively without compromise of urinary continence. Four patients with continent urinary diversions (1 Indiana pouch and 3 Kock pouches) were managed with trans-stomal pouchoscopic ultrasonic lithotripsy (n = 2), prone position extracorporeal shock wave lithotripsy (n = 1), or a "sandwich" combination of these (n = 1) for stone burdens up to 20 cm2. Total hospital stay ranged from one to four (mean = 2.6) days. All 4 patients were initially rendered stone free, and, with follow-up as long as twenty-five months, only 1 has had a recurrence. No patient experienced stomal leakage or other complications. This study suggests that minimally invasive endourologic management of calculi in continent urinary reservoirs can be done safely and effectively to obviate the need for more invasive percutaneous approaches or open surgery, even for some patients with large stone burdens.
Using a conventional body CT scanner, computed tomography of the breast was performed on 32 patients known to have or suspected of having breast masses. Xeromammograms were available for comparison in all cases. All mass lesions were histologically proved. Seven patients were examined prone, 25 supine. The prone position yielded pictures that resembled craniocaudal mammograms. Breast asymmetry, skin thickening, stranding from a mass to the chest wall, calcification, and axillary lymphadenopathy could be demonstrated by means of CT. The portion of the breast adjacent to the chest wall was more readily examined by means of CT than by conventional mammography. Internal mammary nodes could not be demonstrated.
A 10-year retrospective study of the management of airway obstruction in 26 infants with Pierre Robin sequence was made. It was not possible when the infant was first seen to assess the future severity of the airway obstruction but later 3 distinct groups could be identified according to the airway management which had become necessary. The deaths from respiratory obstruction indicate the prime importance of airway management. Laryngoscopy for intubation or endoscopic evaluation was often difficult and sometimes could not be achieved. 'Awake intubation' without general anesthesia has proved to be safer and less difficult using a special purpose slotted laryngoscope. Airway management should be individualized following the progressive sequence of posturing in the prone position, nasopharyngeal tube, endotracheal intubation and tracheotomy until successful control is achieved as indicated by the clinical features and pulse oximetry.
AIM: Analysis of a pilot study including 29 consecutive patients with high surgical risk or refusal of colostomy treated with radiation therapy alone with curative intent. PATIENTS: Between 1986 and 1992, 29 patients were treated for infiltrating adenocarcinoma of the rectum. Median age was 72 years. Transrectal ultrasound staging was used in 24 patients (T1, 2; T2, 14; T3, 13; N0, 23; N1, 6). In 20 patients the lower border of the tumor was at 5 cm or less from the anal verge and in 19 patients the diameter exceeded 3 cm. CEA was elevated in seven cases. TREATMENT: Contact X-ray (50 kV) was given first (70 Gy/3 fractions). External beam radiation therapy used a three-field technique in the prone position. Accelerated schedule (39 Gy/13 fractions/17 days) with a concomitant boost "field within the field' (4 Gy/4 fractions). Six weeks later an iridium-192 implant was performed in 21 (20 Gy/22 h). RESULTS: Median follow-up time was 46 months. Overall and specific survival at 5 years was 68% (SE = 0.09) and 76% (SE = 0.08). Local control was obtained in 21/29 patients (72%). There was one grade 2 rectal bleeding and five grade 2 rectal necroses. The overall tolerance was good in these frail patients. DISCUSSION: For T2. T3 or T1 > 3 cm diameter rectal adenocarcinoma, where contact X-ray alone is not recommended, a combined treatment with radiation therapy alone is able to give good local control with acceptable toxicity. This treatment should be restricted to inoperable patients.
This investigation was carried out by questionnaire to parents of SIDS cases and two controls for each case and aimed to follow up the fact that Tasmania has been shown to have an unusually high rate of this cause of death. Both chi 2 and relative risk calculations were employed. The high rate of SIDS of the 1970s has been confirmed in this series in the 1980s. Many of the epidemiological findings are closely in line with those found internationally. Of particular usefulness are new indications which lie within parental choice; cigarette smoking by parents leading to passive smoking by the baby carries a high relative risk (RR = 3.0, P less than 0.001) as does sleeping in the prone position (RR = 1.9, P less than 0.01) as against sleeping in a lateral position. Tenants of Housing Department homes are at raised risk of SIDS (RR = 2.6, P = 0.001). Density of persons within the home also raises the risks to babies (P less than 0.001) and a well ventilated bedroom lowers the risk (P less than 0.001).
Ultrasound is a useful adjunctive imaging modality to x-ray mammography for the detection and management of breast disease. A high resolution (0.3 mm at -6 dB) transducer consisting of co-axially aligned cone and annular array transducers has been incorporated into a prototype breast imaging system. The prototype scanner had an operating frequency of 4 MHz and scanning was performed in the prone position. We hypothesized that the increased resolution of this system would lead to improved detection of smaller, nonpalpable lesions and would thus contribute to the early detection of breast cancer. Results of a four year clinical study of the prototype involving 1743 patients are reported. The overall true positive (TP) fraction for the detection of malignancy was 52.5% compared with 86.6% for x-ray mammography. Improved performance of ultrasound approaching that of mammography is demonstrated for the youngest age group (less than 34 years) and for women whose breasts are predominantly dysplastic. However, the detection of nonpalpable tumours is disappointing with a TP fraction of only 22%. Causes for the failure of the prototype breast scanner to detect early breast lesions are presented and general conclusions on the use of large aperture transducers for automated breast imaging are discussed.
This paper describes a new approach to the neurolytic block of the celiac plexus through the anterior abdominal wall using CT guidance. In 5 patients, CT guidance was used for needle placement and visualization of the spread of the injection. Once the pain has been relieved on completion of the neurolytic block, the radiologist proceeds with the biopsy. Pain relief was obtained in 80% of the cases after 2 weeks and in 60% after 6 months. No serious complications were observed. The anterior approach is simple and is useful in those patients with upper chronic abdominal pain scheduled for biopsy of the pancreas, and in those terminally ill patients who cannot tolerate the prone position.
Time-course variations in plasma testosterone levels after various periods of immobilization stress (10 min, 30 min, 2 h, 6 h) were examined in male Syrian hamsters. The immobilization stress consisted of placing the animals in a prone position and wrapping them with flexible steel wire gauze. This was done at room temperature. Testosterone levels were determined in blood samples taken after the hamsters were decapitated. Chronic (2 h, 6 h) immobilization stress produced a drastic and enduring fall in plasma testosterone levels. Reduction of plasma testosterone following the 6-h immobilization stress was observed even 18 h after the stress had been relieved. However, acute (10 min, 30 min) immobilization stress did not influence plasma testosterone. These findings indicated that the effect of immobilization stress on plasma testosterone in hamsters was not biphasic, which it is in rats. Further, these results suggest that immobilization stress in hamsters would be a valuable technique with which to investigate the effects of physiological ranges of testosterone on physiological and psychological functions.
The effects of immobilization-induced stress on plasma testosterone levels and lipogenesis in the sebaceous gland were examined in male Syrian hamsters. To induce immobilization stress, the animals were placed in the prone position and wrapped with flexible steel wire gauze at room temperature. Plasma testosterone levels were determined by radioimmunoassay (RIA) of blood samples and sebaceous lipogenesis was determined by measurement of the incorporation of a lipid precursor, 14C-acetate, in ear skin biopsy samples. Both specimens were obtained immediately after the hamsters were decapitated. Immobilization stress for 4 consecutive days produced a marked fall in plasma testosterone levels and sebaceous lipogenesis. These reductions were reversible, the decreased plasma testosterone levels and decreased sebaceous lipogenesis recovering to the nonstressed or prestimulus levels after approximately 1 week. In 4-day stressed animals in occurrence with a decrease in plasma testosterone, sebaceous lipogenesis in ear with topical application of a small dose of testosterone, which have no effect on plasma testosterone level, was equivalent to that in nonstressed animals. These findings indicated that immobilization-induced stress lowered testosterone secretion, and consequently the testosterone levels in the skin, resulting in decreased lipogenesis in the skin. These results thus suggest that psychological or physiological stress can influence cutaneous function by inducing changes in the neuroendocrine system.
A time lag factor of about five days has been identified in an increased incidence of SIDS in relation to a cold day. Sudden exposure to chilling appeared to trigger skeletal muscle weakness and renal failure about five days later in a man found to have only 25% of normal carnitine palmitoyl transferase (CPT) activity in biopsied skeletal muscle. White Muscle Disease is a muscular dystrophy in young ruminants which appears about five days after turnout to pasture in the weaned ruminant raised on a diet deficient in vitamin E and selenium (VESD). Pasture has high levels of linoleic and linolenic acid (high PUFA diet) which are modified by developing rumen bacteria. Corbucci investigated the effects of circulatory shock (cardiogenic) on skeletal muscle mitochondrial activity in humans. Cytochrome oxidase activity fell markedly and, in particular, the capacity to oxidase palmitoyl carnitine was greatly reduced. He considered a consequence of this disorder was sequestration of carnitine as acyl carnitine which could not be recycled. Unusual acyl carnitines have been identified in six out of 13 SIDS victims in a USA group. In Finland, researchers identified a rise in SIDS incidence (mostly found in the prone position) after great and rapid temperature changes. Foster found a relationship between 1984 SIDS incidence and the incidence of goitre in World War I troops.
A technique is described to match the mantle and para-aortic fields used in treatment of Hodgkin's disease, when the patient is treated alternately in supine and prone position. The approach is based on referencing the field edges to a point close to the vertebral column, where uncontrolled motion is minimal and where accurate matching is particularly important. Fiducial surface points are established in the simulation process to accomplish this objective. Dose distributions have been measured to study the combined effect of divergence differences, changes in body angulation and setup errors. Even with the most careful technique, the use of small cord blocks of 50% transmission is an advisable precaution for the posterior fields.
PURPOSE: This article describes the physical, technical, and dosimetric aspects of total body irradiation (TBI). METHODS AND MATERIALS: The continuous head swivel motion of a standard 60Cobalt unit has been used to obtain a sweeping beam that encompasses the entire length of the patient in TBI. A perspex beam flattener designed to remove the inverse square fall-off in beam intensity along the sweep axis provides a 90% field length of 200 cm in air at a treatment source-to-skin distance of 160 cm. The anterior-posterior parallel pair setup permits accurate placement of customized lead compensators to limit the dose to lungs. RESULTS: Measured beam profiles, dose buildup curves, and percentage depth dose for the technique are presented. With compensators in place, the variation in lung dose is shown to be within +/- 5% of the prescribed tumor dose. CONCLUSIONS: A sweeping beam TBI technique has been devised using a standard 60Cobalt unit. The technique allows the patient to be treated in supine and prone positions, which facilitates the accurate placement of lung compensators to limit the dose to lung tissue.
PURPOSE: The various techniques that have been described for treatment of the craniospinal axis show the common challenge of edge matching between adjacent orthogonal and parallel photon beams. Such edge matching is needed because the maximum field length provided by modern treatment machines is generally insufficient to treat adults with less than three matching fields. Using the common techniques, field edge matching becomes difficult, if for medical reasons, the patient cannot be treated in the prone position. METHODS AND MATERIALS: A scanning couch technique is proposed, with the patient lying in supine position. After treating the cerebral and upper neck regions by two lateral opposed half beam fields defined by asymmetric collimators (split beam), the patient is being moved along the spinal axis through an 8.0 cm wide by 15.0 cm long posterior split beam (allowing edge matching with the lateral fields at the neck region) by means of remote controlled couch movement. Stopping and starting of the scanning field resulted in a linear decrease of dose on both sides of the scan. Two ways of resolving this problem were investigated. RESULTS: The administered dose varied less than 8.5% through the craniospinal axis. Flatness of the rectangular scanned field was 0.76%. Apart from dose homogeneity, patient comfort and decreased simulation time are major advantages. CONCLUSIONS: The proposed technique represents a suitable alternative using a common linear accelerator, requiring a remote couch controller as an additional component.
Most SIDS deaths occur between 2 and 4 months of age. Neural transformations may be important in SIDS. Evidence of delayed myelination has been found in SIDS victims. However a simple neuro-developmental model is insufficient to explain SIDS. The age of death profile is reportedly similar for pre-term and full-term SIDS victims. Another developmental change is that IgG levels are lowest when SIDS risk peaks, and there is data linking SIDS and infections. Prone position may also increase risk. While a developmental model emphasizing neural transformation is useful, other factors affect risk also.
The aim of the study was to evaluate the diagnostic accuracy of scintimammography with Tc-99m MIBI for the detection of breast cancer. Patients with a suspicious lesion detected by palpation or mammography were included in the study. Excisional biopsy was performed on all patients. Mammography was performed within 3 weeks prior to scintigraphy. All patients received 740 MBq Tc-99m MIBI intravenously in the arm contralateral to the suspicious breast and were subsequently examined in a prone position. At 5 to 10 min postinjection, planar images were obtained in lateral and anterior views, with an acquisition time of 10 min each. After planar imaging, a SPECT study was performed using a two-head camera. Breast cancer was confirmed in 29 out of 68 patients. The tumor size ranged from 6 to 90 mm in diameter. For scintigraphic studies, the overall sensitivity and specificity was 83% and 84%, respectively. However, sensitivity for palpable lesions was 100%. The smallest detectable tumor measured 9 mm in diameter and could be visualized only in the planar scintigram. Using Tc-99m MIBI, axillary lymph node metastases could be detected with a sensitivity of 82%. Scintigraphy with Tc-99m MIBI has a high diagnostic accuracy for the detection of primary breast cancer in patients with a palpable mass. Scintimammography may be used as a complementary method to mammography and help to decrease the number of unnecessary breast biopsies.