MRI thermometry: Fast mapping of RF‐induced heating along conductive wires

Conductive implants are in most cases a strict contraindication for MRI examinations, as RF pulses applied during the MRI measurement can lead to severe heating of the surrounding tissue. Understanding and mapping of these heating effects is therefore crucial for determining the circumstances under which patient examinations are safe. The use of fluoroptic probes is the standard procedure for monitoring these heating effects. However, the observed temperature increase is highly dependent on the positioning of such a probe, as it can only determine the temperature locally. Temperature mapping with MRI after RF heating can be used, but cooling effects during imaging lead to a significant underestimation of the heating effect. In this work, an MRI thermometry method was combined with an MRI heating sequence, allowing for temperature mapping during RF heating. This technique may provide new opportunities for implant safety investigations. Magn Reson Med, 2008. © 2008 Wiley‐Liss, Inc.     

Penetration of left and right atrial wall and aortic root by an Amplatzer atrial septal occluder in a nine year old boy with Marfan syndrome: Case report

Background  

To describe complications associated with Amplatzer septal occluders in a patient with Marfan syndrome     

Intraoperative assessment of femoral component rotational alignment in total knee arthroplasty

Poor clinical results following total knee arthroplasty like flexion gap instability or anterior knee pain may be related to femoral component rotational malalignment. The transepicondylar axis has been recommended as a landmark to consistently recreate a balanced flexion gap. However, the reproducibility to identify the transepicondylar axis intraoperatively is low. In this feasibility study we wanted to find out whether fluoroscopy-based CT scans obtained by a motorized mobile C-arm (Iso C 3D) may be useful to asses the transepicondylar axis intraoperatively. Following the femoral resections the Iso C 3D was used intraoperatively in ten knees with mild to severe deformities. On multiplanar reconstructions of the distal femur the clinical epicondylar axis as well as the angle to the posterior cut (condylar twist angle) could be easily measured. The scanning time was 40 s and the extra time needed for the whole setup about five to ten minutes. The Iso C 3D was helpful to intraoperatively identify the transepicondylar axis and the condylar twist angle, especially in cases with severe deformity or dysplasia when standard landmarks are difficult to determine. Florian Geiger and Dominik Parsch contributed equally to this article.     

Crossed screws versus dorsomedial locking plate with compression screw for first metatarsocuneiform arthrodesis: a cadaver study

BACKGROUND: We hypothesized that a dorsomedial locking plate with adjunct screw compression would provide superior rigidity compared to crossed screws for first metatarsocuneiform (MTC) arthrodesis. MATERIALS AND METHODS: In ten matched lower extremity pairs, specimens in each pair were randomly assigned to receive screw fixation or plate with screw fixation. Bone mineral density (BMD) was measured. For the crossed-screw construct, two 4.0-mm cannulated screws were used. One screw was inserted dorsal to plantar beginning from the first metatarsal 10 to 15 mm distal to the joint, and the second was inserted from the cuneiform 8 to10 mm proximal to the joint, medial to the first screw, into the first metatarsal. For the plate construct, a 4.0-mm cannulated compression screw was inserted from the dorsal cortex of the first metatarsal to the plantar aspect of the medial cuneiform. A locking plate was inserted dorsomedially across the MTC joint. Specimens were loaded in four-point bend configuration (displacement rate, 5 mm/min) until failure of the fixation or 3-mm deformation. An extensometer was used to measure deformation. RESULTS: There was no difference in load to failure or stiffness between the two groups. BMD was positively correlated with load to failure in the screw (r = 0.893, p = 0.001) and the plate (r = 0.858, p = 0.001) construct. CONCLUSION: The plate construct with compression screw did not show different rigidity as compared with the screw construct with the numbers available. CLINICAL RELEVANCE: Further investigation of a dorsomedial plate with adjunct screw compression may be warranted for first MTC arthrodesis.     

Satisfaction and regret after open retropubic or robot-assisted laparoscopic radical prostatectomy

BACKGROUND: To counsel patients adequately, it is important to understand the variables influencing satisfaction and regret following prostatectomy. OBJECTIVE: To identify independent predictors for satisfaction and regret after radical prostatectomy. DESIGN, SETTING, AND PARTICIPANTS: Patients who had undergone retropubic radical prostatectomy (RRP) or robot-assisted laparoscopic radical prostatectomy (RALP) between 2000 and 2007 were mailed cross-sectional surveys composed of sociodemographic information, the Expanded Prostate Cancer Index Composite (EPIC), and questions regarding satisfaction and regret. MEASUREMENTS: Sociodemographic variables, perioperative complications, type of procedure, length of follow-up, and EPIC scores were evaluated as independent predictors of satisfaction and regret in multivariate logistic regression analysis. RESULTS AND LIMITATIONS: A total of 400 patients responded (response rate 61%) of whom 84% were satisfied and 19% regretted their treatment choice. In multivariate analysis, lower income (odds ratio [OR], 0.08; 95% confidence interval [CI], 0.03-0.23), shorter follow-up (OR, 0.63; 95% CI, 0.41-0.98), having undergone RRP versus RALP (OR, 4.45; 95% CI, 1.90-10.4)], urinary domain scores (OR, 2.70; 95% CI, 1.60-4.54), and hormonal domain scores (OR, 2.01; 95% CI, 1.30-3.12) were independently associated with satisfaction (p相似文献   

15 years experience with microvascular free tissue transfert for repair of head and neck cancer defects

We present the modalities and results obtained with free flap reconstruction of head and neck cancers defects. This retrospective review of 165 free transfers performed between 1984 and 1999 included 89 radial forearm flaps (54%), 38 latissimus dorsi flaps (23%), 28 osteomyocutaneous flaps (17%), 6 omentum flaps (4%), 2 jejunum flaps, and 2 cutaneous scapular flaps. Indications were orobuccopharynx (34%), hypopharynx (24%), mandible (17%), craniofacial (15%) and skin (10%) defects. Flap failure rate was 9%. Reconstruction of a radiated site was a statistically significant indicator of flap failure. Four types of free flaps were preferred for reconstruction of head and neck cancer defects. The radial forearm flap was used as a lap flap for the orobuccopharynx, the tubuled radial forearm flap for reconstruction of the digestive tract after total pharyngolaryngectomy, the osteomyocutaneous free fibular flap for pelvimandibulectomy, especially for the anterior arch, the latissimus dorsi flap to fill craniofacial defects, and the free omentum flap for craniofacial complications after radiotherapy.     

Pancreatic injury in severe trauma: early diagnosis and therapy improve the outcome

BACKGROUND: Pancreatic injury is a dangerous complication in multiple injury, and experience with its diagnosis and treatment is usually limited. METHOD: Retrospective analysis of 3,840 patients admitted after multiple trauma from January 1, 1982, until May 31, 2000. RESULTS: A laparotomy was performed in 121 cases (3.15%) due to suspected intra-abdominal lesion. 32% of the patients (39/121) had a pancreatic lesion; 23% (9/39) had a rupture of the major pancreatic duct. Primary laparotomy was performed in 72% of the patients (28/39). Superficial lesions were treated by explorative laparotomy alone (n = 7), debridement and external drainage (n = 20), or necrosectomy and lavage (n = 3). Complex pancreatic lesions were treated by pancreatojejunostomies (n = 5), pancreatic left resections (n = 2), or exploration alone (n = 2). 8 of 39 patients died (20%), 4 intraoperatively. Of the surviving 35 patients, a pancreas-associated complication developed in 8 patients (23%): pancreatic abscesses (n = 4), traumatic pancreatitis (n = 3), pancreatic fistulas (n = 2), and pseudocysts (n = 2). CONCLUSIONS: Pancreatic injury is an infrequent but dangerous complication in severe trauma. Superficial lesions not affecting the major pancreatic duct can be managed by debridement and external drainage. If the major pancreatic duct is ruptured, organ-preserving, complex reconstructive procedures are necessary. When diagnosed timely and treated according to severity and overall situation, pancreatic injuries have an acceptable morbidity, but usually a high mortality.     

Elevated proBNP levels are associated with disease severity,cardiac dysfunction,and mortality in congenital diaphragmatic hernia

BackgroundCardiac dysfunction is a key determinant of outcome in congenital diaphragmatic hernia (CDH). Pro-b-type natriuretic peptide (proBNP) is used as a prognosticator in heart failure and cardiomyopathy. We hypothesized that proBNP levels would be associated with ventricular dysfunction and high-risk disease in CDH.MethodsPatients in the CDH Study Group (CDHSG) from 2015–2019 with at least one proBNP value were included. Ventricular function was determined using echocardiograms from the first 48 h of life.ResultsA total of 2,337 patients were identified, and 212 (9%) had at least one proBNP value. Of those, 3 (1.5%) patients had CDHSG stage A defects, 58 (29.6%) B, 111 (56.6%) C, and 24 (12.2%) D. Patients with high-risk defects (Stage C/D) had higher proBNP compared with low-risk defects (Stage A/B) (14,281 vs. 5,025, p = 0.007). ProBNP was significantly elevated in patients who died (median 14,100, IQR 4,377–22,900 vs 4,911, IQR 1,883–9,810) (p<0.001). Ventricular dysfunction was associated with higher proBNP than normal ventricular function (8,379 vs. 4,778, p = 0.005). No proBNP value was both sensitive and specific for ventricular dysfunction (AUC=0.61).ConclusionAmong CDH patients, elevated proBNP was associated with high-risk defects, ventricular dysfunction, and mortality. ProBNP shows promise as a biomarker in CDH-associated cardiac dysfunction.