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101.
Bangkim Chandra Khangembam Sellam Karunanithi Punit Sharma Sudhir Suman Kc Rajeev Kumar Pramod Kumar Julka Rakesh Kumar Chandrasekhar Bal 《Neuroradiology》2014,56(10):893-902
Introduction
We assessed the validity of “perfusion-metabolism coupling” hypothesis in recurrent glioma with 13N-ammonia (13N-NH3) PET/CT and 18F-fluorodeoxyglucose (18F-FDG) PET/CT.Methods
Fifty-six consecutive patients (age, 38.8?±?12.1 years; 62.5 % males) with histologically proven and previously treated glioma presenting with clinical suspicion of recurrence were prospectively enrolled and evaluated with 13N-NH3 PET/CT and 18F-FDG PET/CT. PET/CT images were evaluated both qualitatively and semiquantitatively. Tumor to white matter uptake ratio (T/W) and tumor to gray matter uptake ratio (T/G) were calculated and analyzed for both the modalities. A combination of clinico-radiological follow-up, repeated imaging, and biopsy (when available) were considered as the reference standard.Results
Based on the reference standard, 27/56 patients had recurrence. 13N-NH3 PET/CT and 18F-FDG PET/CT were concordant in 55/56 patients. Overall sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of 13N-NH3PET/CT were 77.8, 86.2, 84.0, 80.7, and 82.1 %, respectively, and for 18F-FDG PET/CT were 77.8, 89.7, 87.5, 81.2, and 83.9 %, respectively. There was excellent agreement between results of 13N-NH3 PET/CT and 18F-FDG PET/CT (??=?0.964; P?0.001). The performances of 13N-NH3 PET/CT and 18F-FDG PET/CT were not significantly different between high-grade and low-grade glioma (P?=?1.000). A strong positive correlation was noted between the uptake ratios derived on the two modalities (ρ?=?0.866, P?0.001 for T/W; ρ?=?0.918, P?0.001 for T/G).Conclusion
A combination of 13N-NH3 PET/CT and 18F-FDG PET/CT demonstrates that perfusion and metabolism are coupled in recurrent gliomas. These tracers target two different but interrelated aspects of the same pathologic process and can be used as surrogates for each other. 相似文献102.
McNichols RJ Fox MA Gowda A Tuya S Bell B Motamedi M 《Lasers in surgery and medicine》2005,36(4):289-296
BACKGROUND AND OBJECTIVES: Temporary dermal clearing, i.e., reduction in the attenuation coefficient of the dermis and epidermis, may lead to improved laser tattoo removal by providing increased efficiency of laser delivery to embedded ink particles and enabling the use of shorter wavelength visible lasers more effective on certain inks. STUDY DESIGNS/MATERIALS AND METHODS: In a hairless guinea pig model of human tattoo, we tested both intradermal and transdermal application of glycerol, using visual inspection, spectral analysis, and optical coherence tomography techniques to assess effectiveness. In controlled experiments, we compared the outcomes of single laser treatment sessions for both cleared and uncleared tattoo sites using Q-switched 755 and 532 nm lasers on three different inks. RESULTS: Intradermal injection of clearing agents induced dermal clearing but resulted in necrosis and scar. Transdermal application of clearing agents resulted in moderate reversible clearing, which was localized to the superficial layers of the skin and did not result in complications. Statistically significant differences in laser treatment outcome were observed relative to a number of treatment parameters including the treatment of certain tattoos by short wavelength lasers. CONCLUSIONS: Temporary clearing of superficial skin layers may be performed in an apparently safe and reliable manner. Clearing should lead to increased penetration of laser light to tattoos and should, therefore, increase treatment efficiency. Further study is needed to determine the degree to which this change is of clinical value. 相似文献
103.
Andrea DiMartini Lubna Javed Sarah Russell Mary Amanda Dew Mary Grace Fitzgerald Ashok Jain John Fung 《Liver transplantation》2005,11(6):679-683
Alcohol and tobacco use commonly co-occur, with at least 90% of those with an alcohol problem also using tobacco. Thus, 3 years ago when we discovered higher rate of late deaths due to lung and oropharyngeal cancer in patients who had received a transplant for alcoholic liver disease (ALD), we hypothesized that these patients were continuing to expose themselves to tobacco after liver transplantation (post-LTX) and that this behavior was increasing their risk for cancer. We subsequently began a prospective investigation of post-LTX tobacco use in patients having undergone LTX for ALD (n = 172). For 33 recipients we had data starting from our first assessment at 3 months post-LTX and for this subgroup we report on the details of the timing of tobacco use resumption and the redevelopment of nicotine addiction. We found that on average more than 40% are smoking across all time periods. ALD recipients resume smoking early post-LTX, increase their consumption over time, and quickly become tobacco dependent. These data highlight an underrecognized serious health risk for these patients and demonstrate our need for more stringent clinical monitoring and intervention for tobacco use in the pre- and post-LTX periods. 相似文献
104.
Pandey CK Navkar DV Giri PJ Raza M Behari S Singh RB Singh U Singh PK 《Journal of neurosurgical anesthesiology》2005,17(2):65-68
We evaluated the optimal preemptive dose of gabapentin for postoperative pain relief after single-level lumbar diskectomy and its effect on fentanyl consumption during the initial 24 hours in a randomized, double-blinded, placebo-controlled study in 100 patients with American Society of Anesthesiologists physical status I and II. Patients were divided into five groups to receive placebo or gabapentin 300, 600, 900, or 1200 mg 2 hours before surgery. After surgery, patients were transferred to the postanesthesia care unit (PACU). A blinded anesthesiologist recorded the pain scores at time points of 6, 12, 18, and 24 hours in the PACU on a Visual Analog Scale (VAS; 0-10 cm) at rest. Patients received patient-controlled analgesia (fentanyl 1.0 mug/kg on each demand with lockout interval of 10 minutes); total fentanyl consumption during initial 24 hours was recorded. Data were entered into the statistical software package SPSS 9.0 for analysis (one-way analysis of variance and Student-Newman-Keuls test). Patients who received gabapentin 300 mg had significantly lower VAS score at all time points. They consumed less fentanyl (patients who received placebo processed 1217.5 +/- 182.0 versus 987.5 +/- 129.6 mug; P < 0.05). Patients who received gabapentin 600, 900, and 1200 mg had lower VAS scores at all time points than patients who received gabapentin 300 mg (P < 0.05). Increasing the dose of gabapentin from 600 to 1200 mg did not decrease the VAS score, nor did the increasing dose of gabapentin significantly decrease fentanyl consumption (702.5, 635, and 626.5 microg). Thus, gabapentin 600 mg is the optimal dose for postoperative pain relief following lumbar diskectomy. 相似文献
105.
Hammer GB Ramamoorthy C Cao H Williams GD Boltz MG Kamra K Drover DR 《Anesthesia and analgesia》2005,100(5):1283-8, table of contents
The aim of this prospective, randomized, controlled clinical trial was to define the opioid analgesic requirement after a remifentanil (REMI)-based anesthetic with spinal anesthetic blockade (SAB+REMI) or without (REMI) spinal blockade for open-heart surgery in children. We enrolled 45 patients who were candidates for tracheal extubation in the operating room after cardiac surgery. Exclusion criteria included age <3 mo and >6 yr, pulmonary hypertension, congestive heart failure, contraindication to SAB, and failure to obtain informed consent. All patients had an inhaled induction with sevoflurane and maintenance of anesthesia with REMI and isoflurane (0.3% end-tidal). In addition, patients assigned to the SAB+REMI group received SAB with tetracaine (0.5-2.0 mg/kg) and morphine (7 mug/kg). After tracheal extubation in the operating room, patients received fentanyl 0.3 mug/kg IV every 10 min by patient-controlled analgesia for pain score = 4. Pain scores and fentanyl doses were recorded every hour for 24 h or until the patient was ready for discharge from the intensive care unit. Patients in the SAB+REMI group had significantly lower pain scores (P = 0.046 for the first 8 h; P =0.05 for 24 h) and received less IV fentanyl (P = 0.003 for the first 8 h; P = 0.004 for 24 h) than those in the REMI group. There were no intergroup differences in adverse effects, including hypotension, bradycardia, highest PaCO(2), lowest pH, episodes of oxygen desaturation, pruritus, and vomiting. 相似文献
106.
Gauranga Majumdar Sukanta Barai Surendra Kumar Agarwal Shantanu Pande Bipin Chandra Prabhat Tewari 《Indian Journal of Thoracic and Cardiovascular Surgery》2016,32(3):178-183
Objective
Currently, there is no effective paradigm to identify patients who are at risk for renal dysfunction following cardiac surgery. The specific mechanisms of renal injury during surgery are incompletely understood. The aim of the study was to evaluate whether postoperative renal dysfunction can be predicted from intraoperative glomerular filtration rate (GFR).Design
This is a prospective study.Setting
The study was conducted in a tertiary care multi-specialty hospital.Participants and interventions
GFR was measured in 24 patients (mean age 56.6 ± 11.09 years, 20 male) undergoing elective off-pump coronary artery bypass grafting during preoperative period, intraoperative period, 24 h after surgery (ICU GFR), and on the fifth postoperative day (final GFR ).Measurements and main results
Patients were divided into two groups depending upon changes in intraoperative GFR. Group 1 (n = 10): who had a rise in intraoperative GFR in comparison with preoperative baseline measurement. All these 10 (41.7 %) patients with a rise in intraoperative GFR had an uneventful hospital course and achieved an improvement in final GFR. Group 2 (n = 14): 14 (58.3 %) patients had a fall in intraoperative GFR (mean 36.4 %) in comparison with preoperative baseline value. Of these 14 patients, 1 patient required dialysis support and 3 patients required ionotropic support. Among these 14 patients in group two, 7 had deterioration in final GFR (mean 28.7 %), when compared to preoperative baseline value.Conclusion
Postoperative renal dysfunction can be predicted from intraoperative GFR. Patients who have a rise in intraoperative GFR do not develop postoperative renal dysfunction, and only patients with intraoperative fall in GFR are at risk of postoperative renal dysfunction.107.
Bal Krishna Ojha Mazhar Husain Manu Rastogi Anil Chandra Ashish Chugh Nuzahat Husain 《Acta neurochirurgica》2009,151(7):843-847
Objective This is the first report of the simultaneous combined use of trans-sphenoidal and trans-ventricular-endoscopic route for decompression
of a giant pituitary adenoma.
Method A 38 year old man presented to us with symptoms of raised intracranial pressure along with visual and hypothalamic disturbances.
The CT scan revealed destruction of the sella by a large (5 × 3.5 × 2.5 cm) well defined enhancing mass in the sella and suprasellar
region extending laterally up to the cavernous sinuses and both carotid arteries and superiorly into the lumen of the 3rd
ventricle producing obstructive hydrocephalus. On T2WI of the non-contrast MRI scan the mass was iso-intense to grey matter
suggesting the possibility of a firm nature of the adenoma. The tumour was first approached by the standard trans-sphenoidal
route and as predicted from the pre-operative MRI, the tumour was found to be firm and not amenable to suction. After decompression
of the intra-sellar part of the tumour, the intracranial pressure was raised in an attempt to make the remainder of the tumour
descend into the sella but without success. The suprasellar part of the tumour was then simultaneously addressed via a trans-ventricular-endoscopic
route but the firm tumour did not yield to endoscopic instruments viz. biopsy forceps, angiographic catheter and electrosurgical
probes. It was then gently pushed down towards the sella and decompressed piecemeal by using trans-sphenoidal instruments.
The sellar cavity was reconstructed using fat, fascia lata graft and a piece of septal bone.
Results Post-operatively, the patient showed a remarkable improvement of his symptoms of raised intracranial pressure, hypothalamic
dysfunction and visual disturbances. Follow-up imaging at 2 months and 1 year, did not show any residual or recurrent tumour.
Conclusions This novel technique of the combined trans-sphenoidal and simultaneous trans-ventricular-endoscopic approach is a viable option
for patients with giant fibrous pituitary adenoma when the tumour is not yielding to the trans-sphenoidal route alone. 相似文献
108.
Mayil Vahanan Natarajan Jagadesh Chandra Bose J. Viswanath Navin Balasubramanian Mohamed Sameer 《International orthopaedics》2009,33(4):1081-1084
We analysed the results of 24 cases of aggressive benign and malignant tumours of the distal radius treated by resection and
prosthetic replacement between 1995 and 2006. Patient ages ranged from 18 to 74 years, averaging 33 years; 18 were males.
Recurrent giant cell tumour was the most common tumour. The prosthesis used was a bipolar hinge custom mega prosthesis manufactured
locally. Average follow-up was 78 months. The average Musculoskeletal Tumor Society (MSTS) functional score achieved was 75%.
The ten-year prosthesis survival was rate 87.5%. Infection was the most common complication.
Resume Prothèses sur mesure dans les tumeurs du radius distal. Indications de remplacement. Nous avons analysé les résultats de 24 cas de tumeurs malignes et bégnines agressives de l’extrémité distale du radius traitées par résection et prothèses entre 1995 et 2006. Les patients étaient agées de 18 à 74 ans avec un age moyen de 33 ans dont- 18 étaient des hommes. La cause la plus fréquente a été la récidive de tumeur à cellules géantes. La prothèse utilisée était une prothèse bipolaire à charnière sur mesure fabriquée localement. Le suivi moyen a été de 78 mois. Le score moyen MSTS après traitement était de 75%, la courbe de survie à 10 ans de 87,5%. La complication la plus fréquente a été l’infection.相似文献
109.
Randeep Kashyap Parvez Mantry Rajeev Sharma Manoj K. Maloo Saman Safadjou Yanjie Qi Ashok Jain Benedict Maliakkal Charlotte Ryan Mark Orloff 《Journal of gastrointestinal surgery》2009,13(8):1480-1486
Introduction Primary sclerosing cholangitits (PSC) is a progressive fibrosing cholangiopathy eventually leading to end-stage liver disease
(ESLD). While literature for deceased donor liver transplantation (DDLT) for PSC abounds, only a few reports describe live
donor liver transplant (LDLT) in the setting of PSC. We present a single-center experience on survival outcomes and disease
recurrence for LDLT and DDLT for ESLD secondary to PSC.
Aim The aim of this study was to analyze survival outcomes and disease recurrence for LDLT and DDLT for ESLD secondary to PSC.
Patients and Methods A retrospective review of 58 primary liver transplants for PSC-associated ESLD, performed between May 1995 and January 2007,
was done. Patients were divided into two groups based on donor status. Group 1 (n = 14) patients received grafts from living donors, while group 2 (n = 44) patients received grafts from deceased donors. An analysis of survival outcomes and disease recurrence was performed.
Recurrence was confirmed based on radiological and histological criteria.
Results Recurrence of PSC was observed in four patients in LDLT group and seven in DDLT group. Retransplantation was required in one
patient in LDLT group and nine patients in DDLT group. One patient (7%) among LDLT and six patients (14%) among DDLT died.
The difference in patient and graft survival was not statistically significant between the two groups (patient survival, p = 0.60; graft survival, p = 0.24).
Conclusion This study demonstrates equivalent survival outcomes between LDLT and DDLT for PSC; however, the rate of recurrence may be
higher in patients undergoing LDLT. 相似文献
110.
Objectives We prospectively evaluated the safety, feasibility, and efficiency of robotic radical nephrectomy (RRN) for localized renal
tumors (T1-2N0M0) and compared this with laparoscopic radical nephrectomy (LRN).
Materials and methods Between October 2006 to August 2007, a prospective data analysis of 15 cases of renal cell carcinoma (RCC) stage T1-2N0M0,
undergoing RRN was done. These patients were compared with a contemporary cohort of 15 patients of RCC with clinical stage
T1-2N0M0, undergoing LRN. To keep comparison robust, all cases were performed by a single surgeon. Demographic, intra-operative,
post-operative outcomes, pathological characteristics and follow-up data of the two groups were recorded and analyzed statistically.
Results Patients in group A (RRN) experienced significantly (P = 0.001) long operating time than group B (LRN). However, mean estimated blood loss, intra-operative and post-operative complications,
blood transfusion rate, analgesic requirement, hospital stay and convalescence were comparable in two groups (P < 0.05). There was one conversion to open surgery in group A, and none in group B. The mean follow-up was comparable in two
groups (8.3 and 9.1 months, respectively, in group A and B, P = 0.09). There were no local, port-site or distal recurrences in either group.
Conclusions Robotic radical nephrectomy is a safe, feasible and effective for performing radical nephrectomy for localized RCC. Both groups
(RRN and LRN) had comparable intra-operative, peri-operative, post-operative and oncological outcomes except for longer operating
time with increased cost for RRN. In this comparative study, there were no outstanding benefits of RRN observed over LRN for
localized RCC. 相似文献