Role of diffusion weighted imaging and dynamic contrast enhanced magnetic resonance imaging in breast tumors

AbstractPurposeTo evaluate the role of diffusion weighted imaging and dynamic contrast enhanced magnetic resonance imaging in characterization of breast tumors and comparing the results with the histological finding.Patients and methodsFrom January 2011 to January 2015, 71 patients with 74 suspicious breast lesions had performed breast DCE-MRI combined with DWI and the results were compared with the histopathological examination which was used as the standard diagnostic method.ResultsThe study included 71 patients with 74 suspicious breast lesions, there were 38 benign lesions ((51.35%) and 36 malignant lesions (48.65%)).DCE-MRI proved to have a sensitivity of 91.7%, and a specificity of 84.2%. ADC cutoff value to differentiate between benign and malignant lesions was 1.32×103mm2/s (P<0.001). The diffusion weighted MRI proved to have a sensitivity of 94.4%, and a specificity of 92.1%.The combined MRI protocol of DCEMRI and DWI proved to increase the sensitivity and specificity of breast MRI.ConclusionDWI had a higher sensitivity and specificity than DCE-MRI. The combined MRI protocol of DCEMRI and DWI proved to increase sensitivity and specificity of MRI in diagnosis and differential diagnosis of breast lesions

Levator anguli oris muscle based flaps for nasal reconstruction following resection of nasal skin tumours

<p>Abstract</p> <p>Background</p> <p>surgical excision remains the best tool for management of skin tumors affecting nasal skin, however many surgical techniques have been used for reconstruction of the nasal defects caused by excisional surgery. The aim of this work is the evaluation of the feasibility and outcome of levator anguli oris muscle based flaps.</p> <p>Methods</p> <p>Ninety patients of malignant nasal skin tumours were included in this study. Age was ranged from four to 78 years. For small unilateral defects affecting only one side ala nasi, levator anguli oris myocautaneous (LAOMC) flap was used in 45 patients. For unilateral compound loss of skin and mucus membrane, levator anguli oris myocautaneous mucosal (LAOMCM) flap was used in 23 patients. Very large defects; bilateral either LAOMC or LAOMCM flaps combined with forehead glabellar flaps were used to reconstruct the defect in 22 patients.</p> <p>Results</p> <p>Wound dehiscence was the commonest complication. Minor complications, in the form of haematoma and minor flap loss were managed conservatively. Partial flap loss was encountered in 6 patients with relatively larger tumours or diabetic co-morbidity, three of whom were required operative re-intervention in the form of debridement and flap refashioning, while total flap loss was not occurred at all.</p> <p>Conclusions</p> <p>Immediate nasal reconstruction for nasal skin and mucosal tumours with levator anguli oris muscle based flaps (LAOMC, LAOMCM) is feasible and spares the patient the psychic trauma due to organ loss.</p

Evaluation of the efficacy of transient overvoltages suppression measures in different wind farm topologies using SF6 circuit breaker

Abstract Various overvoltage mitigation schemes were used in literature in suppression of switching overvoltages in wind farms. However, the evaluation of how the effectiveness of these mitigation techniques would vary with the change of the wind farm topology is still un-explored territory. The main aim of this paper is to study the effectiveness of four mitigation schemes while using SF6 circuit breaker namely; R–L smart choke, R–C snubber circuit, surge capacitor and pre-insertion resistor (PIR) were studied in four different wind farm topologies; radial, single-sided ring, double-sided ring and star topologies. The topologies were based on a real wind farm located in Zaafrana, Egypt. The results showed that R–L choke to be the most effective scheme for all topologies followed by PIR, R–C snubber and surge capacitor schemes respectively. Their percentage of reduction of overvoltage ranged from 62 to 84% for R–L choke, 33–67% for PIR, 8–25% for R–C snubber circuits and 4–15% for surge capacitors. Also, it was shown that the change of the wind farm topology didn’t affect the order of effectiveness of the mitigation schemes such that R–L remained the most effective and surge capacitor the least effective for all topologies

Ultrasound-guided serratus anterior plane block versus thoracic paravertebral block for perioperative analgesia in thoracotomy

Background: Thoracotomy needs adequate powerful postoperative analgesia. This study aims to compare the safety and efficacy of ultrasound (US)-guided serratus anterior plane block (SAPB) and thoracic paravertebral block (TPVB) for perioperative analgesia in cancer patients having lung lobectomy. Patients and Methods: This clinical trial involved 90 patients with lung cancer scheduled for lung lobectomy randomly divided into three groups according to the type of preemptive regional block. Group TPVB received US-guided TPVB. In Group SAPB, US-guided SAPB was performed. The patients of the control Group received general anesthesia alone. The outcome measures were postoperative visual analog scale (VAS) score, intraoperative fentanyl consumption, time of first rescue analgesic, total dose postoperative analgesic, and drug-related adverse effects. Results: Analgesia was adequate in TPVB and SAPB groups up to 24 h. VAS score was comparable in TPVB and SAPB groups and significantly lower compared to control group up to 9 h postoperatively. At 12 and 24 h, TPVB group had significantly lower VAS score relative to SAPB and control groups. Total intraoperative fentanyl consumption was significantly lower in TPVB and SAPB Groups compared to control group. The majority of TPVB Group cases did not need rescue morphine, while the majority of control group needed two doses (P < 0.001). The hemodynamic variables were stable in all patients. Few cases reported trivial adverse effects. Conclusion: Preemptive TPVB and SAPB provide comparable levels of adequate analgesia for the first 24 h after thoracotomy. TPVB provided better analgesia after 12 h. The two procedures reduce intraoperative fentanyl and postoperative morphine consumption