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31.
Open ring enhancement is considered highly specific for atypical demyelination. In this report we present a patient with a history of headache, ataxia and sensory disturbances in the lower extremities. A cranial MRI scan showed a large frontal lesion with mass effect, midline shift and with open ring enhancement. These findings are characteristics of tumefactive multiple sclerosis. Such lesions can be confused with neoplasms and abscesses. Open ring enhancement may help in differentiating atypical demyelination from a neoplasm or an abscess.  相似文献   
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Concentrations of trace metals judged potentially carcinogenic were determined in samples of amosite, crocidolite, and chrysotiie. The samples included commercial material as shipped, milled and processed material as collected in animal exposure chambers, and International Union Against Cancer (UICC) reference samples. The metals determined were cobalt, nickel, chromium, manganese, and iron. The samples were treated with hydrofluoric acid, the residue taken up with hydrochloric acid, and the determination made by atomic absorption spectrometry. Substantial enrichment of the dusts in nickel and chromium during milling and dissemination was found. Cobalt and nickel content was different from that in UICC samples.  相似文献   
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Treatment of tuberculosis of the spine with neurologic complications   总被引:6,自引:0,他引:6  
Neurologic complications are the most dreaded complication of spinal tuberculosis. The patients who have paraplegia develop in the active stage of tuberculosis of the spine require active treatment for spinal tuberculosis and have a better prognosis than the patients who have paraplegia develop many years after the initial disease has healed. Neurologic dysfunctions in association with active tuberculosis of the spine can be prevented by early diagnosis and prompt treatment. Prompt treatment can reverse paralysis and minimize the potential disability resulting from Pott's paraplegia. When needed, a combination of conservative therapy and surgical decompression yields successful results in most patients with tuberculosis of the spine who have neurologic complications. The vertebral body primarily is affected in tuberculosis; therefore, decompression has to be anterior. Laminectomy is advocated in patients with posterior complex disease and spinal tumor syndrome. Late onset paraplegia is best avoided by prevention of the development of severe kyphosis. Patients with tuberculosis of the spine who are likely to have severe kyphosis develop (< 60 degrees) on completion of treatment should have surgery in the active stage of disease to improve kyphus.  相似文献   
37.
The implications of lighted ureteral stenting in laparoscopic colectomy.   总被引:1,自引:0,他引:1  
OBJECTIVE: The placement of indwelling ureteral catheters during colorectal surgery has been recommended for prevention of ureteral injuries. With the advent of laparoscopic colectomy (LCo), the role of preoperative placement of lighted ureteral stents (LUS) has also become commonplace. We sought to evaluate the value of lighted ureteral stent placement in laparoscopic colectomy. METHODS: Sixty-six patients underwent LCo with LUS inserted preoperatively. Stents were removed in the immediate postoperative period. Two surgeons performed all the colectomies; 32 patients were males and 34 were females. Fifty patients underwent sigmoid colectomy, 4 had abdominoperineal resection, 4 had right colectomy, and 1 each had transverse or subtotal colectomy. Eighteen patients had a diagnosis of cancer, 34 had diverticular disease, and 14 had neoplastic polyps. Forty patients had bilateral and 26 had unilateral stent placement. A review of the incidence of ureteral injuries, hematuria, and anuria as the cause of acute renal failure was accomplished, comparing the unilateral and bilateral stented groups. RESULTS: One (1.5%) patient suffered a left ureteral laceration during sigmoid colectomy. This was managed successfully with stent reinsertion. Sixty-five (98.4%) patients had gross hematuria lasting 2.93 days (1 to 6 days). The cost of bilateral stent placement was $1,504.32. A statistically significant difference occurred in the duration of hematuria (days) between patients who had unilateral (2.5 +/- 0.82) and bilateral stent placement (3.37 +/- 1.05), (P < 0.001). Four patients suffered from anuria, 2 required renal support needing hemodialysis for 3 to 6 days, 3 (75%) had bilateral stents, and 1 (25%) had a unilateral stent. CONCLUSIONS: We recommend the placement of lighted ureteral stents as a valuable adjunct to laparoscopic colectomy to safeguard ureteral integrity. Transient hematuria is common but requires no intervention. Reflux anuria occurs infrequently and is reversible.  相似文献   
38.
Cervical pedicle screws have been reported to be biomechanically superior to lateral mass screws. However, placement of these implants is a technical challenge. The purpose of this investigation was to use an anatomic and a clinical study to evaluate a technique for placement of the pedicle screws in the C7 vertebra using fluoroscopic imaging in only the anteroposterior (A/P) plane. Ten adult cadaver C7 vertebrae were used to record the pedicle width, inclination and a suitable entry point for placement of pedicle screws. A prospective study of 28 patients undergoing posterior instrumentation of the cervical spine with C7 pedicle screw placement was also performed. A total of 55 C7 pedicle screws were placed using imaging only in the A/P plane with screw trajectory values obtained by the anatomic study. Radiographs and CT scans were performed post-operatively. The average posterior pedicle diameter of C7 vertebra was 9.5 ± 1.2 mm in this study. The average middle pedicle diameter was 7.1 mm and the average anterior pedicle diameter was 9.2 mm. The average transverse pedicle angle was 26.8 on the right and 27.3 on the left. CT scans were obtained on 20 of 28 patients which showed two asymptomatic cortical wall perforations. One screw penetrated the lateral wall of the pedicle and another displayed an anterior vertebral penetration. There were no medial wall perforations. The preliminary results suggest that this technique is safe and suitable for pedicle screw placement in the C7 vertebra.  相似文献   
39.

Background:

Anterior decompression with posterior instrumentation when indicated in thoracolumbar spinal lesions if performed simultaneously in single-stage expedites rehabilitation and recovery. Transthoracic, transdiaphragmatic approach to access the thoracolumbar junction is associated with significant morbidity, as it violates thoracic cavity; requires cutting of diaphragm and a separate approach, for posterior instrumentation. We evaluated the clinical outcome morbidity and feasibility of extrapleural retroperitoneal approach to perform anterior decompression and posterior instrumentation simultaneously by single “T” incision outcome in thoracolumbar spinal trauma and tuberculosis.

Patients and Methods:

Forty-eight cases of tubercular spine (n = 25) and fracture of the spine (n = 23) were included in the study of which 29 were male and 19 female. The mean age of patients was 29.1 years. All patients underwent single-stage anterior decompression, fusion, and posterior instrumentation (except two old traumatic cases) via extrapleural retroperitoneal approach by single “T” incision. Tuberculosis cases were operated in lateral position as they were stabilized with Hartshill instrumentation. For traumatic spine initially posterior pedicle screw fixation was performed in prone position and then turned to right lateral position for anterior decompression by same incision and approach. They were evaluated for blood loss, duration of surgery, superficial and deep infection of incision site, flap necrosis, correction of the kyphotic deformity, and restoration of anterior and posterior vertebral body height.

Results:

In traumatic spine group the mean duration of surgery was 269 minutes (range 215–315 minutes) including the change over time from prone to lateral position. The mean intraoperative blood loss was 918 ml (range 550–1100 ml). The preoperative mean ASIA motor, pin prick and light touch score improved from 63.3 to 74.4, 86 to 94.4 and 86 to 96 at 6 month of follow-up respectively. The mean preoperative loss of the anterior vertebral height improved from 44.7% to 18.4% immediate postoperatively and was 17.5% at final follow-up at 1 year. The means preoperative kyphus angle also improved from 23.3° to 9.3° immediately after surgery, which deteriorated to 11.5° at final follow-up. One patient developed deep wound infection at the operative site as well as flap necrosis, which needed debridement and removal of hardware. Five patients had bed sore in the sacral region, which healed uneventfully. In tubercular spine (n=25) group, mean operating time was approximately 45 minutes less than traumatic group. The mean intraoperative blood loss was 1100 ml (750–2200 ml). The mean preoperative kyphosis was corrected from 55° to 23°. Wound healing occurred uneventful in 23 cases and wound dehiscence occurred in only 2 cases. Nine out of 11 cases with paraplegia showed excellent neural recovery while 2 with panvertebral disease showed partial neural recovery. None of the patients in both groups required intensive unit care.

Conclusions:

Simultaneous exposure of both posterior and anterior column of the spine for posterior instrumentation and anterior decompression and fusion in single stage by extra pleural retroperitoneal approach by “T” incision in thoracolumbar spinal lesions is safe, an easy alternative with reduced morbidity as chest and abdominal cavities are not violated, ICU care is not required and diaphragm is not cut.  相似文献   
40.
Histoplasmosis is a rarely reported deep mycotic infection in the Indian context. Oral or oropharyngeal manifestation can occur as an isolated symptom or as part of a disseminated process associated with immunosuppression especially with HIV and diabetes. Five cases of head and neck histoplasmosis accrued over 6 years in a tertiary referral cancer institute were reviewed. All these patients presented clinically as cancer. In three patients, the marked pseudoepitheliomatous hyperplasia led to a mistaken biopsy diagnosis of malignancy following which definitive surgical treatment was performed. The subsequent excision revealed typical features of histoplasmosis. Isolated oral presentation of histoplasmosis can mimic malignancy both clinically as well as pathologically, leading to potentially disastrous consequences. A high index of suspicion in those with overt or hidden immunosuppression and a deep wedge biopsy to demonstrate the organisms in the subepithelial tissue is recommended. This work has been presented in the “Slide seminar on Infections and Infestations” in the IAP-ID pre conference CME in APCON 2006.  相似文献   
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