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Results for “Prone Position”

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At least 1,729 records · Page 96Linked to original sources

PubMed2005

[Transsphenoidal approach with low field MRI for pituitary adenoma].

INTRODUCTION: Appropriate evaluation of resection remains one of the major difficulties of surgical treatment of pituitary adenoma. The transsphenoidal approach does not allow direct visual control. Endoscopy provides useful information but may no distinguish well residual adenoma from the pituitary gland. Intraoperative MRI offers new perspectives for assessing the quality of resection. We report our experience with low field intraoperative MRI in surgical treatment of pituitary adenoma. POPULATION: Intraoperative MRI (Polestar N10, 30 patients and Polestar N20, 17 patients) was performed in 45 consecutive patients undergoing surgery for pituitary adenoma. Thirty-seven patients had a macroadenoma. Patients were in the prone position with the head fixed with a three-pin MRI-compatible headholder. METHOD: Coronal T1 MRI scans with enhancement were acquired pre and per operatively. We compared scans and surgical filling (complete removal). If there was a difference, a surgical control was undertaken. RESULTS: Intraoperative images were unavailable for two patients due to small size of the neck and the pituitary glands which were not in the middle in the field of view. For the others, the pituitary glands were in the field of view and the intraoperative scans could be used for comparison. For four patients, there was a discrepancy between surgeon filling and the intraoperative MRI. A control showed no residual adenoma but hemostatic tissue. CONCLUSION: Low field intraoperative MRI is an excellent technique for controlling the size of pituitary adenoma resection.

Adenoma↗

PubMed2005

[Posterior ankle impingement syndrome: a retrospective study in 21 cases treated surgically].

PURPOSE OF THE STUDY: The purpose of this work was to describe the posterior ankle impingement syndrome and to present a retrospective analysis of results after surgical treatment in 21 patients with a mean five years follow-up. MATERIAL AND METHODS: Twenty-one patients with a posterior ankle impingement syndrome underwent surgery between 1991 and 1999. There were 17 men and four women, mean age 33 years (18-45); 71% practiced sports, half at the competition level. For 71% of the patients, there was an acute fracture with nonunion of the posterior process of the talus; a microtrauma context was identified in 29%. The physical examination revealed pain at passive forced plantar flexion in 94% of patients with limping during exercise in 88%. Plain x-rays showed a long tail on the talus in 87% of the patients, a short tail in 9%, and a trigone bone in 4%. The posterior malleolus (or third tibial malleolus) was remodeled in 9%. Other examinations performed preoperatively completed the topographic analysis: 99Tc bone scintigraphy, computed tomography with 2D reconstruction and horizontal slices, MRI. The patients were placed in the ventral prone position for surgery via a para-achilles approach, medial in ten patients and lateral in eleven. Bone resection with combined arthrolysis of the subtalar and tibiotalar joints was performed in 20 patients (17 with nonunion of the posterior talar process, one with a trigone bone, two with malformed callus of the posterior malleolus). A soft tissue procedure was also performed in three patients (resection of a synovial cyst in one, tenosynovectomy of the long flexor of the great toe in two). RESULTS: All patients were reviewed clinically and radiographically (plain x-rays). The AOFAS score was determined. There were no cases of infection. Mean follow-up was five years (range 3-10). Results were excellent with a mean Kitaoka score of 90/100, varying with cause and type of procedure performed. Only one patient was dissatisfied (Kitaoka score 67/100); this patient presented residual dysesthesia in the territory of the posterior tibial nerve. In 90% of the patients, there was no sign of degeneration of the peritalar joints (two patients exhibited minimal remodeling of the posterior subtalar joint). 90% of the patients were satisfied or very satisfied. DISCUSSION: The posterior ankle impingement syndrome includes several pathological entities with similar clinical expression. It involves both bony and soft tissue elements in the posterior peritalar region. Repeated or acute forced plantar flexion is the main cause. Complementary explorations (bone scintigraphy, CT, MRI) besides standard radiography, are indispensable to obtain a definitive diagnosis and demonstrate the functional and mechanical impairment. Surgical treatment is simple via a posterior approach (posterolateral or posteromedial)) and in our hands has provided very good results without arthritic consequences at mid-term.

Adolescent↗

PubMed1999

Aneurysm of the distal anterior inferior cerebellar artery at the medial branch: a case report and review of the literature.

BACKGROUND: Distal aneurysms of the anterior inferior cerebellar artery (AICA) are rare. Most have been located at the cerebellopontine angle. Only three cases, including ours, located in the medial branch of the AICA have been reported in the literature. METHODS: A 55-year-old female presented with epilepsy that she experienced for the first time. Computed tomography and magnetic resonance imaging revealed no abnormality. Digital subtraction angiography (DSA) disclosed a rare aneurysm at the medial branch of the distal anterior inferior cerebellar artery. In the blood workup on her admission, a mild inflammatory sign was found, and bacterial aneurysm was suggested as the presumptive differential diagnosis. Repeated DSA was performed 3 months after admission, but the aneurysm did not disappear. She then underwent a suboccipital craniotomy in the prone position. RESULTS: The aneurysm was clipped and partially resected for the pathological examination. Histologic examination revealed a true aneurysm. She was discharged without neurological deficit. CONCLUSIONS: In this report, we summarize the previous cases and discuss the location and clinical manifestations of aneurysms of the AICA through a review of the literature.

Angiography, Digital Subtraction↗

PubMed1996

Extracorporeal shock-wave lithotripsy monotherapy in renal pelvic ectopia.

OBJECTIVES: To determine the efficacy of extracorporeal shock-wave lithotripsy (ESWL) in the treatment of urinary stones in pelvic kidneys. METHODS: Fourteen male patients with renal pelvic ectopia and stones were treated with ESWL monotherapy using the unmodified Dornier HM3 lithotriptor with its original generator and ellipsoid. Twelve patients were treated in the prone position using cystoscopically placed ureteral catheters to aid in fluoroscopic localization, whereas 2 patients were treated in the supine position. A review of their stone disease, ESWL treatment, ancillary procedures, outcome, and complications is presented. RESULTS: All pelvic kidneys were free of infection and obstruction in this group. The mean stone burden was 30.2 +/- 37.8. Most patients required a single session (9 of the 14 [64%]), 2 patients required two sessions, and 2 patients required multiple sessions. The average number of shock waves per session was 1689 (range 450 to 3500), with average kilovoltage of 21.5 (range 18 to 24). Eighty-two percent of the patients followed (9 of 11) were stone-free at 3 months. No ancillary endourologic procedures were required to deal with the presenting stones. Obstructive steinstrasse complicated treatment in only 2 patients (14%) and was successfully treated by further ESWL in both patients: in 1 of them, ureteroscopy was needed. CONCLUSIONS: ESWL monotherapy of renal pelvic ectopia stones is very effective and should be considered as the first therapeutic option for these patients, provided that accurate localization of the stone treated and proper positioning of patients that ensures adequate delivery of shock-wave energy can be maintained.

Adolescent↗

PubMed1995

Extracorporeal shock-wave lithotripsy of middle ureteral stones: are ureteral stents necessary?

OBJECTIVES: To ascertain whether insertion of a ureteral stent improves the outcome of middle ureteral (overlying the pelvic bone) stones treated with extracorporeal shock-wave lithotripsy (ESWL). METHODS: Thirty-three patients with middle ureteral stones were treated with ESWL at our institution between October 1991 and October 1994. Twenty-six patients were available for follow-up; 14 patients were treated with stent bypass, 8 were treated in situ, and 4 patients were treated after percutaneous nephrostomy (PCN). All patients were treated initially on an unmodified Dornier HM-3, and all but 4 patients were treated in the prone position on a modified Stryker frame. Follow-up consisted of a plain abdominal radiograph, intravenous urogram, occasionally a retrograde urogram, and a telephone interview. RESULTS: The overall stone-free rate for ESWL alone was 73%, and the efficiency quotient was 69. The stone-free rates after a single treatment for the stent bypass, in situ, and PCN groups were 71%, 63%, and 75%, respectively. Overall, 4% of patients required retreatment, 19% of patients required an auxiliary procedure, and 8% of the patients required hospital or emergency room admissions for renal colic. For stones 10 mm or greater (9), stone-free rates after one treatment for the stent bypass, in situ, and PCN groups were 33%, 33%, and 67%, respectively; for stones less than 10 mm (17), success rates were 82%, 80%, and 100%, respectively. CONCLUSIONS: Pretreatment stinting provides no advantage over in situ ESWL for middle ureteral calculi (Fisher's exact test, P = 1.0). ESWL is a reasonable initial therapy for middle ureteral stones less than 10 mm.

Adult↗

PubMed1995

Percutaneous electrovaporization of upper tract transitional cell carcinoma in patients with functionally solitary kidneys.

OBJECTIVES: We present the first reported experience using percutaneous electrovaporization with both a rollerball and the VaporTrode electrode of large upper tract transitional cell carcinoma (TCC) in 2 individuals with functionally solitary kidneys. METHODS: Under general anesthesia and in the prone position, 2 patients underwent electrovaporization of upper tract TCC through upper pole percutaneous access. Using either a rollerball (Case 1) or the VaporTrode (Case 2) electrode at 200 W pure cutting current, the tumors were completely vaporized. RESULTS: Average operating room time was 145 minutes. Hemostasis was excellent. No significant perioperative complications were noted. A nephrostogram at the end of the procedure revealed no extravasation in either case. There was no appreciable change in serum creatinine. Both patients received postoperative mitomycin (40 mg in 1000 cc normal saline over 20 hours) through the nephrostomy tube. One patient (Case 2) is completely free of disease via antegrade nephroscopy and biopsy at 2 weeks' follow-up. The other patient (Case 1) had two remaining focal areas of tumor via antegrade nephroscopy 3 weeks postoperatively; both lesions were treated with electrovaporization via a flexible electrode through the flexible cystoscope and the VaporTrode, respectively. CONCLUSIONS: Percutaneous electrovaporization of upper tract TCC appears to provide a simple, rapid, and effective endosurgical treatment in properly selected patients. Long-term follow-up will be needed to assess this new treatment modality definitively.

Aged↗

PubMed1996

Quantitative analysis of cutaneous calcitonin gene-related peptide content in response to acute cutaneous mechanical or thermal stimuli and immobilization-induced stress in rats.

The effects of various stimuli on restricted skin areas or immobilization-induced stress on the calcitonin gene-related peptide (CGRP) content in rat skin were examined by radioimmunoassay (RIA) and immunohistochemistry. Various stimuli were delivered to the shaven skin of the medial thigh by pinching, brushing, or contact with a glass tube containing hot (50 degrees C) or ice-water for 2 min. To induce immobilization stress, animals were placed in the prone position and wrapped with flexible wire gauze at room temperature. The cutaneous CGRP content determined by RIA as well as the number of CGRP-immunoreactive nerve fibers of the skin were significantly higher at sites stimulated by pinching or ice-water compared to non-stimulated areas within the same animals. However, after brushing, hot water stimulation or any period (2 min, 30 min, 2 h, 6 h, or 3 days x 6 h) of immobilization stress, no differences in cutaneous CGRP content were observed. Plasma corticosterone levels increased after immobilization stress of 30 min or greater, but plasma CGRP level did not change after any period of immobilization stress. These data suggest that some forms of cutaneous stimulation cause a rapid rise in CGRP content in the skin, while emotional stress does not influence the cutaneous CGRP content.

Animals↗

PubMed1986

Treatment of giant retinal tears combined with proliferative vitreoretinopathy.

Giant retinal tears with foreshortened and stiffened retina secondary to advanced proliferative vitreoretinopathy (PVR) pose a complex problem for the retinal surgeon. In the past, tractional forces on the retina in these eyes have been counteracted temporarily by retinal sutures, retinal incarceration, or retinal tacks, often combined with fluid-gas exchange in the prone position. These techniques are complex and add multiple additional maneuvers to the surgical procedure. The current report describes the use of a simple, stepwise fluid-gas exchange technique with the patient in the supine position in which the expanding gas bubble traps the edge of the stiffened and foreshortened retina against the pigment epithelium. Long-term counteraction of tractional forces was achieved by the use of intraocular silicone oil. Using this technique, 18 of 19 eyes with giant retinal tears and PVR Grade D1 to D3 could be successfully reattached. Four of these successfully reattached eyes had 360 degrees giant retinal tears. The most common and significant complication in our series was the recurrence of periretinal membranes. All 18 eyes that were initially reattached suffered the recurrence of significant periretinal membranes. Four of those 18 eyes developed recurrent interior traction detachments on to four months postoperatively.

Adolescent↗

PubMed1997

Outpatient postoperative fluid-gas exchange after early failed vitrectomy surgery for macular hole.

BACKGROUND: Vitrectomy surgery with fluid-gas exchange and prone positioning has been shown to close macular holes and improve vision. In those eyes that have failed surgery, repeat vitrectomy has been advocated. As an alternative, the authors performed an outpatient postoperative fluid-gas exchange on eyes when the macular hole failed to close after vitrectomy surgery. METHODS: The authors reviewed all cases of failed vitrectomy surgery for macular holes that underwent a postoperative fluid-gas exchange. Eyes were considered to have failed initial surgery if a rim of subretinal fluid surrounded an open full-thickness macular hole. RESULTS: Twenty-three consecutive eyes underwent outpatient fluid-gas exchange 1 week to 8 weeks after vitrectomy surgery. In 17 eyes (74%), fluid-gas exchange resulted in flattening and closure of the macular hole. In all 17 eyes, visual acuity improved 2 or more lines, with 8 (35%) of the 23 eyes achieving 20/50 or better visual acuity. CONCLUSIONS: Postoperative fluid-gas exchange may achieve successful closure of macular holes and improve vision in eyes that have failed surgery for full-thickness macular holes and should be considered as a cost-effective alternative to repeat vitrectomy.

Aged↗

PubMed1998

Treatment of reopened macular hole after vitrectomy by laser and outpatient fluid-gas exchange.

OBJECTIVE: This study aimed to assess a new nonsurgical treatment for patients who have previously undergone vitrectomy for macular hole with either persistent or reopened holes. DESIGN: A prospective, noncomparative, consecutive case series. PARTICIPANTS: Fifteen patients (15 eyes) were studied. INTERVENTION: Patients were treated by an outpatient method consisting of laser photocoagulation to the foveal pigment epithelium followed by fluid-gas exchange with 20% perfluoropropane gas and prone positioning. Patients without known allergy were treated with two doses of oral Diamox (250 mg) and ciprofloxacin (500 mg). MAIN OUTCOME MEASURES: Visual acuity, intraocular pressure, anatomic status of the macular hole, and cataract were the principal outcome measures studied. RESULTS: Thirteen of 15 macular holes were closed successfully with 1 or more procedures. All patients with macular hole closure achieved two lines or greater of vision improvement on Snellen testing. Three patients (20%) achieved 20/40 and nine (60%) achieved 20/80 or better. Three patients required more than one procedure. Four patients developed mild transient ocular hypertension. CONCLUSIONS: The combination of office-based outpatient fluid-gas exchange and laser appears to be a safe and cost-effective alternative to repeat surgery in selected patients with persistent or reopened macular holes after vitrectomy, in whom there are no visible epiretinal membranes, or in whom return to the operating room is undesirable for medical or personal reasons.

Aged↗

PubMed1998

Photocoagulation and fluid-gas exchange to treat persistent macular holes after prior vitrectomy. A pilot study.

OBJECTIVE: This study aimed to determine the efficacy of photocoagulation to the retinal pigment epithelial (RPE) cells and fluid-gas exchange (FGX) in the treatment of persistent macular holes. DESIGN: A clinical trial. PARTICIPANTS: Thirteen eyes of 12 patients who had undergone photocoagulation to the RPE and FGX for persistent macular holes after initial vitrectomy and gas tamponade were examined. All eyes had persistent full-thickness macular holes (diameter range, 290-820 microns; 610 +/- 190, mean +/- standard deviation) and no vitreous cortex around the holes on biomicroscopic examination. INTERVENTION: Argon laser photocoagulation was applied to the RPE in the hole bed, and FGX with 20% sulfur hexafluoride was then performed, followed by 2 weeks with the patient in a prone position. The follow-up period of the patients ranged from 3 to 18 months (10.2 +/- 4.2; mean +/- standard deviation). MAIN OUTCOME MEASURES: Anatomic success and final visual outcome were measured. RESULTS: Macular holes were closed successfully after treatment in 12 (92%) of 13 eyes, and visual acuity improved 2 or more lines in 6 eyes (46%). Two eyes (15%) attained visual acuities of 20/40 or better, and seven eyes (54%) attained 20/67 or better visual acuity. There were no intraoperative complications. Cataract formation or progression was recognized during follow-up in five (83%) of six phakic eyes. CONCLUSIONS: Although this study includes only a small number of patients, it suggests that photocoagulation and FGX can be effective in the treatment of persistent macular holes.

Aged↗

PubMed2001

Can interventional MRI provide an insight into the mechanics of a posterior-anterior mobilisation?

OBJECTIVES: A pilot study aimed to investigate if interventional MRI could detect changes in the spine and surrounding soft tissues as a result of a posteroanterior mobilisation, and to determine if such an effect was specific to the level of application. DESIGN: A prospective pilot study to investigate the kinematics of cervical spine mobilisation. BACKGROUND: Posteroanterior mobilisation is a manual physiotherapy technique that is commonly used as an examination tool and a form of conservative treatment. The efficacy of this technique is controversial and little is known regarding the underlying mechanisms. METHODS: Five control subjects were recruited and written informed consent obtained. Subjects were scanned, using a General Electric Signa SP10 Open Interventional MRI scanner, in the prone position with their necks in either a neutral or flexed position. In each position a posteroanterior mobilisation to the 2nd and 6th cervical vertebrae was performed. Sagittal images of the spine were obtained prior to, during and following the mobilisation. RESULTS: Clear images of vertebral position could be obtained during the application of a posteroanterior mobilisation. Measurements of intervertebral angulation and translation demonstrated little if any motion during the application of a posteroanterior mobilisation, in both a flexed and neutral position. Changes were seen in terms of soft tissue compression and in some instances overall angulation of the cervical spine. CONCLUSIONS: Interventional MRI can produce images of posteroanterior mobilisation. Dynamic imaging of the procedure produced images of unsuitable quality for analysis. The quasi-static images of suggested that the application of a posteroanterior mobilisation to the cervical spine produces minimal if any intervertebral motion, but significant soft tissue deformation of the overlying structures. RELEVANCE STATEMENT: Posteroanterior mobilisation is frequently used in the assessment and management of spinal problems, but the efficacy of the technique remains controversial. This is hampered by the fact that little is known about the mechanisms involved during such a procedure.

Adult↗

PubMed2003

Segmental mobility of the lumbar spine during a posterior to anterior mobilization: assessment using dynamic MRI.

OBJECTIVES: To quantify segmental mobility of the lumbar spine during a posterior to anterior spinal mobilization procedure. DESIGN: Descriptive study using dynamic magnetic resonance imaging. BACKGROUND: The posterior to anterior spinal mobilization procedure is frequently used in the assessment and management of spinal dysfunction. How this procedure influences segmental spinal motion however, is not known. METHODS: Eleven asymptomatic subjects were positioned prone within a vertically open double donut design magnetic resonance imaging system. An anteriorly directed force was applied manually at each lumbar spinous process while magnetic resonance images were obtained continuously in the sagittal plane. The intervertebral angle was used to quantify segmental motion. RESULTS: The direction of motion at the tested segment was always extension, with values ranging from 1.2 (SD 2.2) at L2 to 3.0 (SD 2.3) degrees at L5. When the force was applied at L3, L4 and L5, the non-tested (adjacent) segments also were observed to move into extension. However, when the posterior to anterior force was applied at L1 and L2 the three caudal segments moved into flexion. CONCLUSIONS: Posterior to anterior spinal mobilization consistently caused extension at the tested segment, while the motion of the collective lumbar spine was either an increase or decrease in lordosis depending on the segment at which the force was applied. RELEVANCE: Passive movement techniques are commonly used to identify the symptomatic lumbar segment(s) and can be used as a treatment aimed at increasing mobility and/or decreasing pain. Knowledge of how this procedure influences segmental motion of healthy spines is important in understanding how altered mobility is related to symptoms.

Adult↗

PubMed2000

Partial liquid ventilation for acute respiratory distress syndrome.

PLV represents an intriguing alternative paradigm in the approach to the patient with ALI. Within the past decade, substantial information has become available regarding this technique. Clearly, PLV is feasible in patients with ALI and ARDS, and it appears to be safe with respect to short-term effects on hemodynamics and lung physiology, as well as long-term toxicity (although further research in this area is warranted). Although PLV has not yet been proven to be superior to traditional mechanical ventilation for patients with ALI or ARDS, PLV possesses an intriguing combination of physical, physiologic, and biologic effects: "Liquid PEEP" effect--e.g., more effective recruitment of dependent lung zones than achieved by gas ventilation Anti-inflammatory effects Lavage of alveolar debris Mitigation of ventilator-induced lung injury Direct anti-inflammatory effects--e.g., decreased macrophage release of proinflammatory cytokines, etc. Prevention of nosocomial pneumonia Combination with other modalities--e.g., exogenous surfactant replacement, inhaled NO, prone position Enhanced delivery of drugs or gene vectors into the lung. The results of ongoing and future clinical trials will be necessary to establish whether PLV improves clinical outcomes in patients with ALI or ARDS, or specific subgroups of such patients. Significant work also remains to be done to define the optimum dose level of PLV and the most appropriate ventilatory strategies.

Clinical Trials as Topic↗

PubMed1994

A model to study the transport function of the intestinal viscera during peritoneal dialysis.

A preparation was developed to selectively study the transport properties of the intestinal viscera. A rat was positioned prone on a 100-mL beaker (reservoir) and the viscera were completely immersed and suspended without tension in dialysate solution maintained at 37 degrees C. A volume of 11.6 +/- 0.9 mL was ultrafiltered over a period of 180 minutes with a 5.6% glucose dialysate solution (n = 5) versus 0.5 +/- 0.5 mL for a 1.5% hydrous glucose dialysate solution (n = 4). The suspended viscera were able to absorb glucose from the beaker. The viscera absorbed more glucose when they were suspended in a higher glucose concentration: 922 +/- 46 mg for the 5.6% solution (54% of the initial glucose present) and 151 +/- 13 mg for the 1.5% solution (39% of the initial glucose present). Protein was found to leak from the viscera, and the amount found in dialysate was not related to the concentration of glucose used as dialysate (75 +/- 25 mg for the 5.6% solution and 41 +/- 3 mg for the 1.5% solution; P = NS). Studies also demonstrated transport from blood into the dialysate and that transport into dialysate could be altered by altering visceral blood supply (intravenous infusion of antidiuretic hormone, 800 micrograms/hr). Urea and glucose clearances were greater in the absence of antidiuretic hormone, whereas creatinine and inulin clearances were not different in both groups. This model offers the potential to selectively study the responses of the visceral peritoneum.

Animals↗

PubMed1997

Exogenous surfactant therapy in a patient with adult respiratory distress syndrome after near drowning.

A 24-year-old woman developed adult respiratory distress syndrome (ARDS) after near-drowning due to attempted suicide. Conventional mechanical ventilation together with prone positioning and inhaled nitric oxide could not provide sufficient oxygenation. Surface tension data (gamma min = 27 dyn/cm, stability index = 0.341) from a lavage sample supported the hypothesis that the surfactant function of this patient was drastically reduced due to a washout effect by aspiration of fresh water. Porcine surfactant (Curosurf, 50 mg/kg for each lung) was instilled via fibreoptic bronchoscope. The partial arterial carbon dioxide pressure (paCO2) and fraction of inspired oxygen (FiO2) ratio as well as shunt fraction (Qs/Qt) improved impressively. When respiratory situation deteriorated again, surfactant application was repeated. Altogether, six bolus instillations of surfactant (total dose 300 mg/kg = 18,000 mg) were administered until the respiratory situation had stabilized and oxygenation could be maintained by conventional mechanical ventilation. The radiological findings did not show substantial amelioration. The patient developed septic shock and died 12 days after admission. Surfactant application apparently led to a significant improvement of the respiratory function. However, the outcome could not be influenced positively. The high cost of surfactant therapy prevents the more widespread early administration in patients at risk.

Adult↗

PubMed1999

The cranial-spinal junction in medulloblastoma: does it matter?

PURPOSE: Late effects of treatment in children and young adults with medulloblastoma can be influenced by the technique employed in radiating the craniospinal axis. The purpose of this study is to determine whether the placement of the cranial-spinal junction has an impact on dose to the cervical spinal cord and surrounding organs. METHODS AND MATERIALS: Five patients underwent computed tomography (CT) simulation in the prone position for craniospinal irradiation. A dose of 36 Gy was prescribed to the entire neuraxis. The doses to the cervical spinal cord and surrounding organs were calculated using a cranial-spinal junction at the C1-C2 vertebral interspace (high junction) or at the lowest point in the neck, with exclusion of the shoulders in the lateral cranial fields (low junction). The volume of critical organs at risk, as well as dose to these structures using the cranial and spinal field(s) were outlined and calculated using the CMS FOCUS 3-dimensional treatment planning system. RESULTS: The average dose to the cervical spinal cord was 11.9% higher than the prescribed dose with the low junction, and 6.7% higher with the high junction. However, doses to the thyroid gland, mandible, pharynx, and larynx were increased by an average of 29.6%, 75.8%, 70.6%, and 227.7%, respectively, by the use of the high junction compared to the low junction. CONCLUSION: A higher dose to the cervical spinal cord can be minimized by using a high junction. However, this would be at the cost of substantially increased doses to surrounding organs such as the thyroid gland, mandible, pharynx, and larynx. This can be critical in children and young adults, where hypothyroidism, mandibular hypoplasia, and development of second malignancies may be a late sequela of radiation therapy.

Adolescent↗

PubMed2002

A case of fatal hemorrhage in the cerebral ventricles following intravenous use of methamphetamine.

We describe a case of massive hemorrhage in the cerebral ventricles, probably caused by methamphetamine abuse. A 44-year-old male was found dead in a prone position in a hotel room. Old and new injection marks were observed in his right cubital fossa. Petechiae were observed on the conjunctiva of his right eye, laryngeal mucosa, epicardium and under the capsule of the liver (to a slight or moderate degree). The brain, weighing 1.67 kg, was heavily edematous; the lateral and fourth ventricles were filled with hematomas. Subarachnoid, intracerebral hemorrhages were not observed. Cerebral vascular abnormalities were not evident. There were no remarkable changes in other organs, other than congestion. Gas chromatographic-mass spectrometric analysis of the urine disclosed the presence of methamphetamine and amphetamine. The concentration of methamphetamine within the femoral venous blood and intraventricular hematoma was 0.347 microg/ml and 0.189 microg/g, respectively. Amphetamine was not detected in either sample. Urine contained 3.15 microg/ml methamphetamine and 0.063 microg/ml amphetamine. These results indicate that intraventricular hemorrhage might have occurred shortly after intravenous self-administration of methamphetamine. Cerebral arterial spasm and hypertension resulting from the administration of methamphetamine might have resulted in intraventricular hemorrhage.

Acetic Anhydrides↗