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71.
Magnetic resonance (MR) images of the brain in 285 patients between the ages of 2 and 25 years were retrospectively studied to determine the appearance of brain iron accumulation. The globus pallidus, red nucleus, substantia nigra, and dentate nucleus were evaluated with long TR/TE (repetition time/echo time) spin-echo sequences and staged. All four regions in most patients were initially hyperintense compared with white matter (stage I) before becoming isointense (stage II) and subsequently hypointense (stage III). The globus pallidus was the first to reach stage III, the red nucleus and substantia nigra were next, and the dentate nucleus was last. In general, decreased signal intensity (stage III) was not seen in these regions in patients less than 10 years old; in most patients it was seen by age 25 years. The dentate nucleus decreased in signal intensity more slowly and inconsistently; only one-third of patients had reached stage III by age 25 years. The temporal sequence of normal iron deposition as detected with MR imaging is helpful not only in the diagnosis of known iron-deposition diseases but also in the detection of iron-related pathologic changes.  相似文献   
72.
Osteomyelitis: detection with US   总被引:2,自引:0,他引:2  
Abiri  MM; Kirpekar  M; Ablow  RC 《Radiology》1989,172(2):509-511
To evaluate the role of ultrasound (US) in the detection of osteomyelitis, the authors prospectively studied 48 patients clinically suspected of having osteomyelitis. A sonographic diagnosis was made if fluid was seen directly in contact with bone, without intervening soft tissues. Twelve of the 48 patients were subsequently found to have osteomyelitis. In 10 of them, US demonstrated abnormal fluid adjacent to the bone. This fluid was thought to represent an inflammatory exudate dissecting in a subperiosteal and/or extraperiosteal location. Eight of the 48 patients had soft-tissue fluid collections. The rest of the patients either had no abnormalities or had cellulitis. The authors conclude that US can be useful in the detection of osteomyelitis.  相似文献   
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Background

Recent advances in total knee arthroplasty (TKA) include an intelligent instrument system designed to provide intraoperative guidance to reduce mechanical alignment errors. Internal position-sensing technology is integrated into microelectronic pods that attach to cutting blocks. The purpose of this prospective, randomized study was to determine whether this iAssist system enables the surgeon to make more accurate bone resections and better restore the mechanical axis compared to conventional instruments in TKA.

Methods

We randomized patients undergoing TKA into 2 groups. Group I (n = 25) underwent TKA assisted by the iAssist guidance system, group II (n = 25) underwent TKA using conventional instruments. Preoperative and postoperative mechanical axes were measured from full-length lower extremity radiographs to evaluate alignment. Additional surgical parameters were also assessed, including tourniquet time and blood loss.

Results

Patient demographics and preoperative mechanical axis alignments were similar between the groups. Postoperatively, 4.0% of patients had greater than 3° of tibial or femoral component mal-alignment in the guidance-assisted cohort, compared with 36.0% in the conventional group (P < .05). Additionally, group I showed significant improvement in variance seen in both the femoral mechanical axis (1.65° ± 0.17° vs 2.23° ± 0.33°, P < .005) and tibial mechanical axis (1.28° ± 0.13° vs 1.71° ± 0.24°, P < .005) compared to group II. There were no significant differences in tourniquet time (P = .86) or blood loss (P = .39) between groups.

Conclusion

Use of the iAssist system in TKA results in an improved postoperative mechanical axis and decreased alignment variability compared to conventional instruments, without significantly increasing operative time.  相似文献   
74.
IntroductionThe Royal College of Surgeons of England (RCS) has issued guidance regarding the use of reoperation rates in the revalidation of UK-based orthopaedic surgeons. Currently, little has been published concerning acceptable rates of reoperation following primary surgical management of orthopaedic trauma, particularly with reference to revalidation.MethodsA retrospective review was conducted of patients undergoing clearly defined reoperations following primary surgical management of trauma between 1 January 2010 and 31 December 2011. A full case note review was undertaken to establish the demographics, clinical course and context of reoperation. A review of the imaging was performed to establish whether the procedure performed was in line with accepted trauma practice and whether the technical execution was acceptable.ResultsA total of 3,688 patients underwent primary procedures within the time period studied while 70 (1.90%, 99% CI: 1.39–2.55) required an unplanned reoperation. Thirty-nine (56%) of these patients were male. The mean age of patients was 56 years (range: 18–98 years) and there was a median time to reoperation of 50 days (IQR: 13–154 days). Potentially avoidable reoperations occurred in 41 patients (58.6%, 99% CI: 43.2–72.6). This was largely due to technical errors (40 patients, 57.1%, 99% CI: 41.8–71.3), representing 1.11% (99% CI: 0.73–1.64) of the total trauma workload. Within RCS guidelines, 28-day reoperation rates for hip, wrist and ankle fractures were 1.4% (99% CI: 0.5–3.3), 3.5% (99% CI: 0.8%–12.1) and 1.86% (99% CI: 0.4–6.6) respectively.ConclusionsWe present novel work that has established baseline reoperation rates for index procedures required for revalidation of orthopaedic surgeons.  相似文献   
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76.
Although iron, vltamm B12, and folate deficiency have been well documented after gastric bypass operations performed for morbid obesity, there is surprisingly little information on either the natural course or the treatment of these deficiencies in Roux-en-Y gastric bypass (RYGB) patients Durmg a l0-year period, a complete blood count and serum levels of iron, total iron-binding capacity, vltamin B12, and folate were obtained in 348 patients preoperatively and postoperatively at 6-month intervals for the first 2 years, then annually thereafter The principal objectives of this study were to determine how readily patients who developed metabolic deficiencies after Roux-en-Y gastric bypass responded to postoperative supplements of the deficient micronutrient and to learn whether the risk of developmg these deficiencies decreases over time Hemoglobin and hematocrit levels were slgnificantly decreased at all postoperative intervals in comparison to preoperative values Moreover, at each successive interval through 5 years, hemoglobin and hematocrit were decreased signifiantly compared to the preceding interval Folate levels were significantly increased compared to preoperative levels at all time intervals Iron and vltamin B12 levels were lower than preoperative measurements and remained relatively stable postoperatively Half of the low hemoglobin levels were not associated with iron deficiency Taking multivltamin supplements resulted in a lower incidence of folate deficiency but did not prevent iron or vitamin B12 deficiency Oral supplementation of iron and vitamin B12 corrected defiaencies in 43% and 81% of cases, respectively Folate deficiency was almost always corrected with multivitamins alone No patient had symptoms that could be attributed to either vitamin B12 or folate deficiency Conversely, many patients had symptoms of iron deficiency and anenua Lack of symptoms of vitamin B12 and folate deficiency suggests that these deficiencies are not clinically important after RYGB Conversely, iron deficiency and anemia are potentially serious problems after RYGB, particularly in younger women Hence we recommend prophylactic oral iron supplements to premenopausal women who undergo RYGB  相似文献   
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In a retrospective study conducted at the University of Alabama at Birmingham, the University of Michigan, and the Mayo Clinic, 185 patients with previously untreated FIGO stage IB and IIA squamous cell carcinoma of the cervix were found to have nodal metastasis at the time of radical hysterectomy and pelvic lymphadenectomy. Of these patients, 103 received adjuvant pelvic irradiation. Cancer recurred in 76 patients; the median time to recurrence was 3.1 years. The prognostic significance of patient age, clinical stage, lesion diameter, number and location of nodal metastases, and use of adjuvant radiation therapy was determined by multivariate analysis. Only patient age (P = 0.0006), lesion diameter (P less than 0.0001), and number of nodal metastases (P = 0.0004) were noted to be significant factors in determining overall survival. Rates of recurrence were also related to these factors. Employment of these significant variables led to identification of four risk groups. In general, patients with small cervical lesions (diameter less than 1 cm) and no more than two nodes with metastases fell into the low-risk category; those patients with large cervical lesions (diameter greater than 4 cm) and more than two involved nodes fell into the high-risk category. All other patients were categorized into intermediate-risk groups. Ten-year survival was 92% in the low-risk group (n = 13), 70% in the low-intermediate-risk group (n = 66), 56% in the high-intermediate-risk group (n = 66), and 13% in the high-risk group (n = 20). This risk group classification identifies subgroups of early-stage cervical carcinoma patients found to have nodal metastasis at the time of radical hysterectomy that warrant appropriately selected adjuvant therapy.  相似文献   
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