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41.

Background

To determine neurologic outcome in patients with out-of-hospital cardiac arrest (OHCA) and treatment with mild therapeutic hypothermia (MTH).

Methods

Seventy-three consecutive OHCA patients treated with MTH were retrospectively analyzed. Serum neuron-specific enolase (NSE) was measured 24, 48, and 72 h after admission. In patients with no motor response 48 h after termination of analgosedation (n = 40), clinical neurological examination and evoked potentials (EPs) were determined. Neurological outcome was assessed after 2 months based on the cerebral performance categories (CPC), and categorized as good (CPC 1–3) or poor (CPC 4 and 5).

Results

Forty-three patients had a CPC score of 1–3 and 30 patients had a CPC 4–5. The best predictive value for poor neurologic outcome was an increase of NSE by ≥4.3 ng/mL between day 1 and day 2 (sensitivity 80 %, specificity 100 %, positive predictive value (PPV) 100 %, negative predictive value 86 %). Absolute NSE values were less reliable in the prediction of poor outcome with the highest sensitivity (88 %) and specificity (95 %) if values reached ≥36.3 ng/mL on day 3. Somatosensory EPs (SSEPs) showed a specificity of 100 % and PPV of 100 %; however, sensitivity for evoked potentials was low (29 %). Intriguingly, two initially comatose patients with excessive NSE values (24 h NSE: 101 and 256 ng/mL, and 48 h NSE: 93 and 110 ng/mL, respectively) had physiological SSEPs and regained a CPC score of 1.

Conclusion

In patients treated with MTH after OHCA changes in NSE are more suitable than its absolute serum levels for the prediction of poor neurologic outcome. Since unequivocal prediction of poor neurologic outcome is of utmost importance in these patients the decision to limit therapy must be based on several prediction tools with the highest PPV and specificity including SSEPs.  相似文献   
42.
Nucleotide sequences and the deduced amino acid sequences of the gene encoding the matrix (M) protein of the Nishigahara and the CVS strains of rabies virus have been determined. The M gene is 609 nucleotides long and is capable of coding for a peptide composed of 202 amino acids. Sequence comparison of these M genes with those of other stains [Pasteur (PV), ERA, Avol] revealed that there is 89.7–91.5% homology at the nucleotide level, and 90.1–92.1% homology at amino acid level, between almost all combinations of these strains. However, in the combinations of the PV and ERA strains, and the virulent CVS and the avirulent CVS-derived Avol strains, much higher homology was observed both at the nucleotide and amino acid levels. The predicted secondary structure and hydropathy profiles also exhibited similar features. Recombinant vaccinia virus containing the M gene was constructed. Sodium dodecyl sulfate (NaDodSO4)-polyacrylamide gel electrophoresis of the precipitates obtained by immune reaction of the recombinant virus-infected cell lysate with a monoclonal antibody against the M protein revealed that electrophoretic mobility of the expressed protein is indistinguishable from that of the authentic M protein from rabies virions.The nucleotide sequence data of the M genes of the CVS and Nishigahara (RCEH) strains reported in this paper will appear in the DDBJ, EMBL, and GenBank Nucleotide Sequence Databases under the accession numbers D90450 and D90451.  相似文献   
43.

Objectives

To investigate whether amide proton transfer (APT) MR imaging can differentiate high-grade gliomas (HGGs) from low-grade gliomas (LGGs) among gliomas without intense contrast enhancement (CE).

Methods

This retrospective study evaluated 34 patients (22 males, 12 females; age 36.0?±?11.3 years) including 20 with LGGs and 14 with HGGs, all scanned on a 3T MR scanner. Only tumours without intense CE were included. Two neuroradiologists independently performed histogram analyses to measure the 90th-percentile (APT90) and mean (APTmean) of the tumours’ APT signals. The apparent diffusion coefficient (ADC) and relative cerebral blood volume (rCBV) were also measured. The parameters were compared between the groups with Student’s t-test. Diagnostic performance was evaluated with receiver operating characteristic (ROC) analysis.

Results

The APT90 (2.80?±?0.59 % in LGGs, 3.72?±?0.89 in HGGs, P?=?0.001) and APTmean (1.87?±?0.49 % in LGGs, 2.70?±?0.58 in HGGs, P?=?0.0001) were significantly larger in the HGGs compared to the LGGs. The ADC and rCBV values were not significantly different between the groups. Both the APT90 and APTmean showed medium diagnostic performance in this discrimination.

Conclusions

APT imaging is useful in discriminating HGGs from LGGs among diffuse gliomas without intense CE.

Key Points

? Amide proton transfer (APT) imaging helps in grading non-enhancing gliomas ? High-grade gliomas showed higher APT signal than low-grade gliomas ? APT imaging showed better diagnostic performance than diffusion- and perfusion-weighted imaging
  相似文献   
44.
OBJECTIVE: To differentiate acute from chronic graft occlusions through diameter measurements by means of electron beam tomography (EBT). METHODS: Contrast enhanced EBT volume studies were carried out in 37 patients with one or more occluded venous coronary bypass grafts. Seventeen of 37 patients did not meet the inclusion criteria and were excluded from the assessment. The remaining 20 patients had a total of 39 bypasses (16 patent, 23 occluded) and were assigned to one of three groups: group A consisted of patent grafts only (patent grafts, 13 patients). Group B comprised 11 of 23 occluded grafts diagnosed within 10 days after bypass surgery (acutely occluded grafts, ten patients). Group C contained 12 of 23 bypass occlusions that were at least 6 months old as documented by coronary angiography (chronically occluded grafts, ten patients). The mean graft diameter was determined by repetitive measurements on a workstation through blinded readers. The Mann-Whitney-U-test for unpaired samples was used for statistical evaluation. RESULTS: Mean graft diameter for groups A-C (patent, acutely, and chronically occluded bypasses, respectively) was 3.9 mm (+/-0.6; n=16), 5.4 mm (+/-1.9; n=11), and 0.3 mm (+/-.9; n=12), respectively (P<0.01 each). Sensitivity and specificity for the detection of acute and chronic occlusions were 87 and 92% (cut-off 4.5 mm), respectively, and 92 and 96% (cut-off 1 mm), respectively. CONCLUSIONS: EBT may allow for non-invasive differentiation between acute and chronic venous coronary bypass occlusions. This could help prevent unnecessary invasive recanalization procedures. Body veins may conserve their ability to increase in diameter in acute thrombosis when transplanted as coronary bypasses.  相似文献   
45.
BACKGROUND: We present data showing the impact of sequential multisegmental aortic clamping accompanied by reimplantation of as many segmental arteries as possible on the prevention of postoperative paraplegia or paraparesis during thoracoabdominal aortic graft replacement. METHODS: Since 1987 we have performed graft replacements in 51 individuals undergoing thoracoabdominal aortic surgery using the technique of normothermic partial bypass with sequential multisegmental aortic clamping. The procedure was performed emergently in 10 patients and electively in 41 patients. The patients ranged in age from 22 to 82 years (mean, 57.6 +/- 13.8 years). Indications for surgery included dissecting thoracoabdominal aortic aneurysm (n = 19) and nondissecting thoracoabdominal aortic aneurysm (n = 32). The extent of aneurysm was Crawford type I in 19 patients, type II in 7 patients, type III in 12 patients, and type IV in 13 patients. Along the entire extent of aneurysm to be replaced, we reimplanted as many of the patent segmental arteries as feasible. RESULTS: Five patients died during hospitalization, for an in-hospital mortality rate of 9.8%. The number of aortic clampings per patient ranged from one to five (median, three). A total of 124 segmental arteries were reimplanted in 44 (86.3%) of 51 patients. Of the 124 arteries, 90 (72.6%) were distributed between T9 and L2. Postoperative paraplegia or paraparesis did not develop in any of the patients. CONCLUSIONS: Our results demonstrate that extensive reimplantation of segmental arteries using sequential multisegmental aortic clamping, accompanied by adequate intraoperative distal aortic perfusion, is effective in preventing spinal cord ischemia.  相似文献   
46.
PURPOSE: The purpose of this study was to evaluate the use of radionuclide angiography and single photon emission computed tomography (SPECT) using Tc-99m hexakis-2-methoxyisobutylisonitrile (Tc-99m MIBI) for analyzing musculoskeletal lesions. MATERIALS AND METHODS: Radionuclide angiography and SPECT using Tc-99m MIBI were performed in 36 patients with various soft tissue and bone pathologies (18 benign and 18 malignant lesions). The ratio of the counts of the lesion to that of the contralateral normal area was calculated from the region of interest drawn on the MIBI scan. The MIBI-uptake ratio was calculated using SPECT and the MIBI-perfusion index was calculated using radionuclide angiography. RESULTS: The MIBI-uptake ratio in malignant lesions (4.80 +/- 4.43) was significantly higher (P < 0.05) than that in benign lesions (1.83+/-2.48). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the MIBI-uptake ratio for malignant lesions were 72%, 83%, 78%, 81%, and 75%, respectively. The MIBI-perfusion index in malignant lesions (17.68 +/- 21.19) was significantly higher (P < 0.05) than that in benign lesions (2.25 +/- 2.56). The sensitivity, specificity, accuracy, positive predictive value, and negative predictive value of the MIBI-perfusion index for malignant lesions were 87%, 75%, 81%, 77%, and 86%, respectively. CONCLUSIONS: The MIBI-uptake ratio and MIBI-perfusion index using Tc-99m MIBI can yield important additional information with which to differentiate musculoskeletal lesions.  相似文献   
47.
We have routinely used an intraoperative CT (i-CT) system in over 800 neurosurgical procedures since 1997. To investigate the utility of i-CT in low-grade glioma (LGG) surgery, we investigated whether i-CT improved the extent of tumor resection and prognosis in 46 patients with histologically confirmed LGG consisting of 27 patients with World Health Organization grade II astrocytoma, 12 with oligodendroglioma, and 7 with oligoastrocytoma. The patients were divided into two groups, 23 who underwent tumor resection without i-CT (non i-CT group) and 23 who underwent surgery using i-CT (i-CT group). We investigated the extent of tumor resection, pre- and postoperative Karnofsky performance status scores, and overall survival in each group. The extent of tumor resection was biopsy 26.1%, partial resection 60.9%, subtotal resection 13.0%, and gross total resection 0% in the non i-CT group, and 4.4%, 21.7%, 34.8%, and 39.1%, respectively, in the i-CT group. The i-CT group showed significantly longer overall survival than the non i-CT group among patients with astrocytoma (p < 0.05) and oligodendroglioma or oligoastrocytoma (p < 0.005). Prolonged survival was related to the extent of resection. There were no significant differences between pre- and postoperative Karnofsky performance status scores between the groups. Surgical resection using i-CT may improve the outcomes of patients with LGG. Additional resection or emergency treatment can be quickly performed as the surgical results are confirmed intraoperatively or immediately after the operation using i-CT.  相似文献   
48.
We experienced the anesthetic management of a 39 year-old-male with hereditary spastic paraplegia (HSP) associated with pain due to pes cavus. He underwent orthomorphia ostectomy and tenodesis. Preoperative neurological examination revealed that he had slight dementia, symptoms of the pyramidal tract, lower limb bathyhypesthesia, and neurogenic bladder in addition to spastic paraplegia, and he was diagnosed as having combined type of HSP. Spinocerebellar degeneration is often accompanied with this type of HSP. To avoid the use of muscle relaxants and narcotics, we tried to induce anesthesia with inhalation of nitrous oxide (N2O), oxygen and sevoflurane (sevo). A laryngeal mask (LM) was inserted at the expiratory concentration of sevo 3.5%. Anesthesia was maintained by N2O, oxygen and sevo (2-3%) under spontaneous respiration. The patient recovered from anesthesia after the end of surgery, and the LM was removed smoothly. The patient's respiratory condition was stable, and no problems were found in the postoperative period.  相似文献   
49.
The aim of this study was to evaluate the use of 124I positron emission tomography (PET) to determine the dosimetry of radioiodine therapy in hyperthyroidism and thyroid cancer. Phantom studies to assess the accuracy of PET were performed using an EEC phantom with spheres of different diameters filled with 3-30 MBq of 124I. Patient dosimetry was derived from PET data obtained 1-13 days after simultaneous oral administration of a therapeutic dose of 131I and a diagnostic dose of 124I. The obtained data were compared with findings from intratherapeutic probe measurements and clinical outcome. The phantom studies confirmed that 124I can be quantitated by PET (imprecision < or =10%), and volumetry is feasible for nodules <13 mm (imprecision < or =20%). Any influence of contamination with 123I or the simultaneous administration of 131I on the accuracy of the PET quantification and the probe measurements was ruled out by phantom measurements with solutions of 131I, 124I and 123I in various ratios. In autonomous nodular goitres, radioiodine uptake measured by PET varied from 25.4% to 64.3% and was not significantly different from that obtained by a scintillation probe (24.1%-73.1%, correlation coefficient r=0.91). Comparison of uptake and effective half-life in normal tissue versus autonomous nodules revealed significant differences in uptake but not in effective half-life [uptake 2.0-8.3 kBq/(ml x MBq) in normal tissue vs 12.6-29.3 kBq/(ml x MBq) in nodules; half-life 97.8-156.7 h in normal tissue vs 73.3-192.3 h in nodules]. Calculated radiation doses ranged between 177 and 633 Gy for autonomous nodules and between 47 and 126 Gy for normal tissue. In thyroid cancer patients, doses between 350 and 1,420 Gy were achieved in thyroid remnants and between 70 and 170 Gy in tumour metastases. It is concluded that 124I and PET are suitable for evaluation of the dosimetry of radioiodine therapy in benign and malignant thyroid diseases. The applied technique might be particularly useful for quantitative dose-response studies in radioiodine treatment and further investigations of stunning phenomena.  相似文献   
50.
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