Endoscopic transnasal resection of anterior cranial fossa meningiomas.

PubMed

de Divitiis, Enrico; Esposito, Felice; Cappabianca, Paolo; Cavallo, Luigi M; de Divitiis, Oreste; Esposito, Isabella

2008-01-01

The extended transnasal approach, a recent surgical advancements for the ventral skull base, allows excellent midline access to and visibility of the anterior cranial fossa, which was previously thought to be approachable only via a transcranial route. The extended transnasal approach allows early decompression of the optic canals, obviates the need for brain retraction, and reduces neurovascular manipulation. Between 2004 and 2007, 11 consecutive patients underwent transnasal resection of anterior cranial fossa meningiomas--4 olfactory groove (OGM) and 7 tuberculum sellae (TSM) meningiomas. Age at surgery, sex, symptoms, and imaging studies were reviewed. Tumor size and tumor extension were estimated, and the anteroposterior, vertical, and horizontal diameters were measred on MR images. Medical records, surgical complications, and outcomes of the patients were collected. A gross-total removal of the lesion was achieved in 10 patients (91%), and in 1 patient with a TSM only a near-total (> 90%) resection was possible. Four patients with preoperative visual function defect had a complete recovery, whereas 3 patients experienced a transient worsening of vision, fully recovered within few days. In 3 patients (2 with TSMs and 1 with an OGM), a postoperative CSF leak occurred, requiring a endoscopic surgery for skull base defect repair. Another patient (a case involving a TSM) developed transient diabetes insipidus. The operative time ranged from 6 to 10 hours in the OGM group and from 4.5 to 9 hours in the TSM group. The mean duration of the hospital stay was 13.5 and 10 days in the OGM and TSM groups, respectively. Six patients (3 with OGMs and 3 with TSMs) required a blood transfusion. Surgery-related death occurred in 1 patient with TSM, in whom the tumor was successfully removed. The technique offers a minimally invasive route to the midline anterior skull base, allowing the surgeon to avoid using brain retraction and reducing manipulation of the large vessels and

Semantic memory is impaired in patients with unilateral anterior temporal lobe resection for temporal lobe epilepsy.

PubMed

Lambon Ralph, Matthew A; Ehsan, Sheeba; Baker, Gus A; Rogers, Timothy T

2012-01-01

Contemporary clinical and basic neuroscience studies have increasingly implicated the anterior temporal lobe regions, bilaterally, in the formation of coherent concepts. Mounting convergent evidence for the importance of the anterior temporal lobe in semantic memory is found in patients with bilateral anterior temporal lobe damage (e.g. semantic dementia), functional neuroimaging and repetitive transcranial magnetic stimulation studies. If this proposal is correct, then one might expect patients with anterior temporal lobe resection for long-standing temporal lobe epilepsy to be semantically impaired. Such patients, however, do not present clinically with striking comprehension deficits but with amnesia and variable anomia, leading some to conclude that semantic memory is intact in resection for temporal lobe epilepsy and thus casting doubt over the conclusions drawn from semantic dementia and linked basic neuroscience studies. Whilst there is a considerable neuropsychological literature on temporal lobe epilepsy, few studies have probed semantic memory directly, with mixed results, and none have undertaken the same type of systematic investigation of semantic processing that has been conducted with other patient groups. In this study, therefore, we investigated the semantic performance of 20 patients with resection for chronic temporal lobe epilepsy with a full battery of semantic assessments, including more sensitive measures of semantic processing. The results provide a bridge between the current clinical observations about resection for temporal lobe epilepsy and the expectations from semantic dementia and other neuroscience findings. Specifically, we found that on simple semantic tasks, the patients' accuracy fell in the normal range, with the exception that some patients with left resection for temporal lobe epilepsy had measurable anomia. Once the semantic assessments were made more challenging, by probing specific-level concepts, lower frequency

Semantic memory is impaired in patients with unilateral anterior temporal lobe resection for temporal lobe epilepsy

PubMed Central

Ehsan, Sheeba; Baker, Gus A.; Rogers, Timothy T.

2012-01-01

Contemporary clinical and basic neuroscience studies have increasingly implicated the anterior temporal lobe regions, bilaterally, in the formation of coherent concepts. Mounting convergent evidence for the importance of the anterior temporal lobe in semantic memory is found in patients with bilateral anterior temporal lobe damage (e.g. semantic dementia), functional neuroimaging and repetitive transcranial magnetic stimulation studies. If this proposal is correct, then one might expect patients with anterior temporal lobe resection for long-standing temporal lobe epilepsy to be semantically impaired. Such patients, however, do not present clinically with striking comprehension deficits but with amnesia and variable anomia, leading some to conclude that semantic memory is intact in resection for temporal lobe epilepsy and thus casting doubt over the conclusions drawn from semantic dementia and linked basic neuroscience studies. Whilst there is a considerable neuropsychological literature on temporal lobe epilepsy, few studies have probed semantic memory directly, with mixed results, and none have undertaken the same type of systematic investigation of semantic processing that has been conducted with other patient groups. In this study, therefore, we investigated the semantic performance of 20 patients with resection for chronic temporal lobe epilepsy with a full battery of semantic assessments, including more sensitive measures of semantic processing. The results provide a bridge between the current clinical observations about resection for temporal lobe epilepsy and the expectations from semantic dementia and other neuroscience findings. Specifically, we found that on simple semantic tasks, the patients’ accuracy fell in the normal range, with the exception that some patients with left resection for temporal lobe epilepsy had measurable anomia. Once the semantic assessments were made more challenging, by probing specific-level concepts, lower frequency

High stoma prevalence and stoma reversal complications following anterior resection for rectal cancer: a population-based multicentre study.

PubMed

Holmgren, K; Kverneng Hultberg, D; Haapamäki, M M; Matthiessen, P; Rutegård, J; Rutegård, M

2017-12-01

Fashioning a defunctioning stoma is common when performing an anterior resection for rectal cancer in order to avoid and mitigate the consequences of an anastomotic leakage. We investigated the permanent stoma prevalence, factors influencing stoma outcome and complication rates following stoma reversal surgery. Patients who had undergone an anterior resection for rectal cancer between 2007 and 2013 in the northern healthcare region were identified using the Swedish Colorectal Cancer Registry and were followed until the end of 2014 regarding stoma outcome. Data were retrieved by a review of medical records. Multiple logistic regression was used to evaluate predefined risk factors for stoma permanence. Risk factors for non-reversal of a defunctioning stoma were also analysed, using Cox proportional-hazards regression. A total of 316 patients who underwent anterior resection were included, of whom 274 (87%) were defunctioned primarily. At the end of the follow-up period 24% had a permanent stoma, and 9% of patients who underwent reversal of a stoma experienced major complications requiring a return to theatre, need for intensive care or mortality. Anastomotic leakage and tumour Stage IV were significant risk factors for stoma permanence. In this series, partial mesorectal excision correlated with a stoma-free outcome. Non-reversal was considerably more prevalent among patients with leakage and Stage IV; Stage III patients at first had a decreased reversal rate, which increased after the initial year of surgery. Stoma permanence is common after anterior resection, while anastomotic leakage and advanced tumour stage decrease the chances of a stoma-free outcome. Stoma reversal surgery entails a significant risk of major complications. Colorectal Disease © 2017 The Association of Coloproctology of Great Britain and Ireland.

EFFICACY OF THE ANTERIOR RESECTION IN MANAGMENT OF ACUTE COLONIC OBSTRUCTION IN PATIENTS WITH RECTAL CANCER.

PubMed

Minasyan, A; Sargsyan, R

2016-10-01

The aim of this study is to improve the results of surgical treatment of acute bowel obstruction caused by rectal cancer and to reduce the period of full recovery of patients. The presented research included 73 patients (study group) with rectal cancer who underwent emergent anterior resection of rectum with loop ileostomy and intra-operative decompression of colon. Patients of this group were compared to a group of 68 patients (control group) with the same diagnosis who underwent Hartmann's procedure. There was no essential difference between the two groups in the quantity of postoperative complications. However the results indicate significant difference in reversal rates and time to reversal. Thus, the technique of low anterior resection with intraoperative decompression and ileostomy that we used improves outcomes, significantly reduces the period of full recovery.

Substantial underreporting of anastomotic leakage after anterior resection for rectal cancer in the Swedish Colorectal Cancer Registry.

PubMed

Rutegård, Martin; Kverneng Hultberg, Daniel; Angenete, Eva; Lydrup, Marie-Louise

2017-12-01

The causes and effects of anastomotic leakage after anterior resection are difficult to study in small samples and have thus been evaluated using large population-based national registries. To assess the accuracy of such research, registries should be validated continuously. Patients who underwent anterior resection for rectal cancer during 2007-2013 in 15 different hospitals in three healthcare regions in Sweden were included in the study. Registry data and information from patient records were retrieved. Registered anastomotic leakage within 30 postoperative days was evaluated, using all available registry data and using only the main variable anastomotic insufficiency. With the consensus definition of anastomotic leakage developed by the International Study Group on Rectal Cancer as reference, validity measures were calculated. Some 1507 patients were included in the study. The negative and positive predictive values for registered anastomotic leakage were 96 and 88%, respectively, while the κ-value amounted to 0.76. The false-negative rate was 29%, whereas the false-positive rate reached 1.3% (the vast majority consisting of actual leaks, but occurring after postoperative day 30). Using the main variable anastomotic insufficiency only, the false-negative rate rose to 41%. There is considerable underreporting of anastomotic leakage after anterior resection for rectal cancer in the Swedish Colorectal Cancer Registry. It is probable that this causes an underestimation of the true effects of leakage on patient outcomes, and further quality control is needed.

Reconstruction of the anterior skull base after major trauma or extensive tumour resection.

PubMed

König, Stefan Alexander; Ranguis, Sebastian; Gramlich, Veronika; Spetzger, Uwe

2015-01-01

The authors describe their experience with the reconstruction of complex anterior skull base defects after trauma or tumour resection using a "sandwich" technique with pericranial flap, titanium mesh and TachoSil. Description of surgical anatomy, surgical technique, indications, limitations, complications, specific perioperative considerations and specific information to give to the patient about surgery and potential risks. A summary of ten key points is given. After a bifrontal craniotomy and a subfrontal approach, it is possible to achieve a reliable reconstruction of the anterior skull base in a watertight manner by fixing a pericranial flap or a fascia lata graft to the orbital roofs and planum sphenoidale with an individually tailored titanium mesh and closing the frontobasal dura leasion with TachoSil.

Ultralow anterior resection with mechanical anastomosis in the treatment of distal third rectal cancer.

PubMed

Espín, Eloy; Sánchez García, José Luis; Vallribera, Francesc

2014-03-01

Tumors of the lower third of the rectum are a challenge for the surgeon. Among the various techniques of surgical treatment of these lesions, radical surgery and ultra low anterior anastomosis is one of the therapeutic options. This technique is a defy both in the evaluation of the potential patient as in the surgical technique. Such evaluation and treatment processes must be audited in order to keep proper quality indices both in the oncological as in their functional results. This is only possible when both the multidisciplinary and surgical teams have an adequate and ongoing specialized training and a satisfactory volume of patients treated. Details of this technique, its indications and results are reported in this paper. Copyright © 2014 Asociación Española de Cirujanos. Published by Elsevier Espana. All rights reserved.

Single incision vs conventional laparoscopic anterior resection for sigmoid colon cancer: a case-matched study.

PubMed

Kwag, Seung-Jin; Kim, Jun-Gi; Oh, Seong-Taek; Kang, Won-Kyung

2013-09-01

The purpose of the study was to evaluate the safety and effects of single-incision laparoscopic anterior resection (SILAR) for sigmoid colon cancer by comparing it with conventional laparoscopic anterior resection (CLAR). Twenty-four patients who underwent SILAR between April 2010 and July 2011 were case matched 1:2 with patients who underwent CLAR, with respect to age, sex, body mass index, tumor location, and history of abdominal surgery. Two patients in the SILAR group and 1 patient in the CLAR group experienced anastomotic leakage. The operative time was longer in the SILAR group than in the CLAR group (251 ± 50 vs 237 ± 49 minutes; P = .253). The number of harvested lymph nodes (19.6 ± 10.7 vs 20.8 ± 7.7; P = .630) was not different. The postoperative hospital stay was shorter in the SILAR group (7.1 ± 3.4 days) than in the CLAR group (8.1 ± 3.5 days) (P = .234). On the basis of the early outcomes, we conclude that SILAR is feasible and safe. Moreover, the adequate lymph node harvest and free margins support the use of this procedure. Copyright © 2013 Elsevier Inc. All rights reserved.

Resection of a ventral intramedullary cervical spinal cord cavernous malformation through an anterior approach.

PubMed

Weil, Alexander G; Bhatia, Sanjiv

2014-09-01

Ventrally-located intramedullary cervical spinal cord cavernomas are rare entities in the pediatric population. Surgical access to these lesions is challenging. The authors present the complete resection of a symptomatic ventral cervical intramedullary cavernoma through an anterior approach in a 15-year-old boy. The lesion was accessed following left anterolateral dissection, C3-4 discectomy and C3/C4 partial corpectomy. The authors will discuss the rationale for intervening in this patient and for selecting this anterior approach over other approaches, such as the anterolateral, posterolateral or posterior approach. The steps, pitfalls and pearls of this surgical approach will be demonstrated in a detailed video. The video can be found here: http://youtu.be/-ARTp6g13hgs.

Comparison of intracorporeal single-stapled and double-stapled anastomosis in laparoscopic low anterior resection for rectal cancer: a case-control study.

PubMed

Kim, Hye Jin; Choi, Gyu-Seog; Park, Jun Seok; Park, Soo Yeun

2013-01-01

Recently, a single-stapled technique (SST) was performed instead of the conventional double-stapled technique (DST) in laparoscopic low anterior resection for anastomosis, by placement of intracorporeal purse-string sutures on the distal rectum with transanal specimen extraction. This study aimed to compare the short-term outcomes between the two anastomotic techniques. Between July 2007 and April 2010, 60 patients underwent SST by laparoscopic or robotic procedure. These patients were matched 1:2 by age, gender, date of surgery, and tumor stage with 120 patients who underwent conventional DST in laparoscopic low anterior resection. The robotic-assisted operative approach was used more frequently in the SST group than in the DST group (61.7 % vs. 3.3 %, p < 0.001). The mean operative time was 203.9 (range, 120-400) min for the SST group and 167.6 (range, 90-300) min for the DST group (p < 0.001). For specimen removal, the transanal approach was used in the SST group, while the transabdominal approach was used for the DST group. The pain score (visual analogue scale) of the SST group was lower (4.5 vs. 5.6, p < 0.001), although postoperative recovery was similar. Pathological examination revealed that the distal resection margin was significantly longer in the SST group (3.1 vs. 2.5 cm, p = 0.018). Postoperative morbidity including anastomotic leakage was similar in both groups. SST yielded equivalent short-term outcomes when compared to conventional DST and provided the advantages of minimal access and a longer distal resection margin. Therefore, SST in lower anterior resection may be a useful alternative to conventional DST.

Comparison of abdominoperineal resection and low anterior resection in lower and middle rectal cancer.

PubMed

Omidvari, Shapour; Hamedi, Sayed Hasan; Mohammadianpanah, Mohammad; Razzaghi, Samira; Mosalaei, Ahmad; Ahmadloo, Niloofar; Ansari, Mansour; Pourahmad, Saeideh

2013-09-01

This study aimed to investigate local control and survival rates following abdominoperineal resection (APR) compared with low anterior resection (LAR) in lower and middle rectal cancer. In this retrospective study, 153 patients with newly histologically proven rectal adenocarcinoma located at low and middle third that were treated between 2004 and 2010 at a tertiary hospital. The tumors were pathologically staged according to the 7th edition of the American Joint Committee on Cancer (AJCC) staging system. Surgery was applied for 138 (90%) of the patients, of which 96 (70%) underwent LAR and 42 were (30%) treated with APR. Total mesorectal excision was performed for all patients. In addition, 125 patients (82%) received concurrent (neoadjuvant, adjuvant or palliative) pelvic chemoradiation, and 134 patients (88%) received neoadjuvant, adjuvant or concurrent chemotherapy. Patients' follow-up ranged from 4 to 156 (median 37) months. Of 153 patients, 89 were men and 64 were women with a median age of 57 years. One patient (0.7%) was stage 0, 15 (9.8%) stage I, 63 (41.2%) stage II, 51 (33.3%) stage III and 23 (15%) stage IV. There was a significant difference between LAR and APR in terms of tumor distance from anal verge, disease stage and combined modality therapy used. However, there was no significant difference regarding 5-year local control, disease free and overall survival rates between LAR and APR. LAR can provide comparable local control, disease free and overall survival rates compared with APR in eligible patients with lower and middle rectal cancer. Copyright © 2013. Production and hosting by Elsevier B.V.

Similar Outcome After Colonic Pouch and Side-to-End Anastomosis in Low Anterior Resection for Rectal Cancer

PubMed Central

Machado, Mikael; Nygren, Jonas; Goldman, Sven; Ljungqvist, Olle

2003-01-01

Objectives To compare a colonic J-pouch or a side-to-end anastomosis after low-anterior resection for rectal cancer with regard to functional and surgical outcome. Summary Background Data: A complication after restorative rectal surgery with a straight anastomosis is low- anterior resection syndrome with a postoperatively deteriorated anorectal function. The colonic J-reservoir is sometimes used with the purpose of reducing these symptoms. An alternative method is to use a simple side-to-end anastomosis. Methods: One-hundred patients with rectal cancer undergoing total mesorectal excision and colo-anal anastomosis were randomized to receive either a colonic pouch or a side-to-end anastomosis using the descending colon. Surgical results and complications were recorded. Patients were followed with a functional evaluation at 6 and 12 months postoperatively. Results: Fifty patients were randomized to each group. Patient characteristics in both groups were very similar regarding age, gender, tumor level, and Dukes’ stages. A large proportion of the patients received short-term preoperative radiotherapy (78%). There was no significant difference in surgical outcome between the 2 techniques with respect to anastomotic height (4 cm), perioperative blood loss (500 ml), hospital stay (11 days), postoperative complications, reoperations or pelvic sepsis rates. Comparing functional results in the 2 study groups, only the ability to evacuate the bowel in <15 minutes at 6 months reached a significant difference in favor of the pouch procedure. Conclusions: The data from this study show that either a colonic J-pouch or a side-to-end anastomosis performed on the descending colon in low-anterior resection with total mesorectal excision are methods that can be used with similar expected functional and surgical results. PMID:12894014

Solo-Surgeon Single-Port Laparoscopic Anterior Resection for Sigmoid Colon Cancer: Comparative Study.

PubMed

Choi, Byung Jo; Jeong, Won Jun; Kim, Say-June; Lee, Sang Chul

2018-03-01

To report our experience with solo-surgeon, single-port laparoscopic anterior resection (solo SPAR) for sigmoid colon cancer. Data from sigmoid colon cancer patients who underwent anterior resections (ARs) using the single-port, solo surgery technique (n = 31) or the conventional single-port laparoscopic technique (n = 45), between January 2011 and July 2016, were retrospectively analyzed. In the solo surgeries, making the transumbilical incision into the peritoneal cavity was facilitated through the use of a self-retaining retractor system. After establishing a single port through the umbilicus, an adjustable mechanical camera holder replaced the human scope assistant. Patient and tumor characteristics and operative, pathologic, and postoperative outcomes were compared. The operative times and estimated blood losses were similar for the patients in both treatment groups. In addition, most of the postoperative variables were comparable between the two groups, including postoperative complications and hospital stays. In the solo SPAR group, comparable lymph nodes were attained, and sufficient proximal and distal cut margins were obtained. The difference in the proximal cut margin significantly favored the solo SPAR, compared with the conventional AR group (P = .000). This study shows that solo SPAR, using a passive camera system, is safe and feasible for use in sigmoid colon cancer surgery, if performed by an experienced laparoscopic surgeon. In addition to reducing the need for a surgical assistant, the oncologic requirements, including adequate margins and sufficient lymph node harvesting, could be fulfilled. Further evaluations, including prospective randomized studies, are warranted.

Oncologic outcomes of single-incision versus conventional laparoscopic anterior resection for sigmoid colon cancer: a propensity-score matching analysis.

PubMed

Kim, Chang Woo; Cho, Min Soo; Baek, Se Jin; Hur, Hyuk; Min, Byung Soh; Kang, Jeonghyun; Baik, Seung Hyuk; Lee, Kang Young; Kim, Nam Kyu

2015-03-01

The aim of this study was to investigate oncologic outcomes, as well as perioperative and pathologic outcomes, of single-incision laparoscopic anterior resection (SILAR) compared with conventional laparoscopic anterior resection (CLAR) for sigmoid colon cancer using propensity-score matching analysis. From July 2009 through April 2012, a total of 407 patients underwent laparoscopic anterior resection for sigmoid colon cancer. Data on short- and long-term outcomes were collected prospectively and reviewed. Propensity-score matching was applied at a ratio of 1:2 comparing the SILAR (n = 60) and CLAR (n = 120) groups. There was no difference in operation time, estimated blood loss, time to soft diet, and length of hospital stay; however, the SILAR group showed less pain on postoperative day 2 (mean 2.6 vs. 3.6; p = 0.000) and shorter length of incision (3.3 vs. 7.7 cm; p = 0.000) compared with the CLAR group. Morbidity, mortality, and pathologic outcomes were similar in both groups. The 3-year overall survival rates were 94.5 versus 97.1% (p = 0.223), and disease-free survival rates were 89.5 versus 87.4% (p = 0.751) in the SILAR and CLAR groups, respectively. The long-term oncologic outcomes, as well as short-term outcomes, of SILAR are comparable with those of CLAR. Although SILAR might have some technical difficulties, it appears to be a safe and feasible option, with better cosmetic results.

Combined operative technique with anterior surgical approach and video-assisted thoracoscopic surgical lobectomy for anterior superior sulcus tumours.

PubMed

Yokoyama, Yuhei; Chen, Fengshi; Aoyama, Akihiro; Sato, Toshihiko; Date, Hiroshi

2014-11-01

Video-assisted thoracoscopic surgery (VATS) has been widely used, but surgical resections of superior sulcus tumours remain challenging because of their anatomical location. For such cases, less-invasive procedures, such as the anterior transcervical-thoracic and transmanubrial approaches, have been widely performed because of their excellent visualization of the subclavian vessels. Recently, a combined operative technique with an anterior surgical approach and VATS for anterior superior sulcus tumours has been introduced. Herein, we report three cases of anterior superior sulcus tumours successfully resected by surgical approaches combined with a VATS-based lobectomy. In all cases, operability was confirmed by VATS, and upper lobectomies with hilar and mediastinal lymph node dissections were performed. Subsequently, dissections of the anterior inlet of the tumours were performed using the transmanubrial approach in two patients and the anterior trans-cervical-thoracic approach in one patient. Both approaches provided excellent access to the anterior inlet of the tumour and exposure of the subclavian vessels, resulting in radical resection of the tumour with concomitant resection of the surrounding anatomical structures, including the chest wall and vessels. In conclusion, VATS lobectomy combined with the anterior surgical approach might be an excellent procedure for the resection of anterior superior sulcus tumours. © The Author 2014. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Low-grade fibrosarcoma of the anterior skull base: endoscopic resection and repair.

PubMed

Kuhn, Frederick A; Javer, Amin R

2003-01-01

Fibrosarcomas of the paranasal sinuses and skull base are uncommon tumors. Traditionally, "open approach" surgery remains the mainstay for treatment of choice for these tumors. A 49-year-old man underwent resection of a right anterior skull base fibrosarcoma using the endoscopic approach. Close follow-up using both endoscopic and imaging methods over a period of four years has revealed a well-healed skull base with no evidence of recurrence. Significant resistance exists at present for such a technique to deal with malignant diseases of the head and neck but results from advanced centers continue to prove that this may be a technique worth mastering and improving on.

Long-term Evaluation of a Modified Double Staple Technique for Low Anterior Resection.

PubMed

Illuminati, G; Carboni, F; Ceccanei, G; Pacilè, M A; Pizzardi, G; Palumbo, P; Vietri, F

2014-01-01

When performing low anterior resection for rectal cancer with the double staple technique, -closing the rectum with a linear stapler in the abdomen can be challenging, especially when dealing with a narrow pelvis. For such instances we proposed to modify this technique by pulling the rectal stump through the anus, doing an extra-anal resection of the tumor and linear suture of the rectal stump, before performing a standard, stapled colorectal anastomosis. The purpose of this study was to assess the adequacy of this modification of the double staple technique. Retrospective review of 108 patients undergoing a stapled, low colorectal or coloanal anastomosis, after -eversion, extra-anal resection of the tumor and linear closure of the rectal stump for colorectal cancer, from January 1990 to December 2012. Operative mortality was 0.9%. Fourteen patients (13%) presented early, surgery-related complications -consisting of 7 anastomotic leaks, 5 wound infections, 1 ureteral lesion, and 1 peristomal abscess. Late complications related to surgery included 5 incisional hernias (4.6%), 4 anastomotic strictures (3.7%), 4 neurogenic bladders (3.7%) and 2 fecal incontinences (1.8%). The incidence of local disease recurrence was 10%. Surgical and oncological results validate the proposed modification of the double staple technique, when facing difficulties in suturing the rectum from the abdomen. Copyright© Acta Chirurgica Belgica.

Use of the stapler in anterior resection for cancer of the rectosigmoid.

PubMed

Resnick, S D; Burstein, A E; Viner, Y L

1983-02-01

The circular stapling device was used for anterior resection in 61 of 88 patients who underwent curative surgery for rectosigmoid cancer. Use of the autosuture increased the success rate to 68.5% for this radical sphincter-saving procedure. In three-quarters of the patients the stapling end-to-end inverting colorectal anastomosis was created within 3 to 8 cm from the dentate line, where it is difficult or even impossible to perform anastamoses by the conventional manual technique. Anastomotic leakage (3.3%) and hemorrhage (4.9%), mild anastomotic stenosis (1.6%) and transitory anal incontinence (4.9%) were the main complications. There were no deaths in our series. The great safety of the stapling anastomosis and the low rate of anal incontinence may be explained by the preservation of an adequate blood supply and innervation of the rectal stump and its sphincter apparatus, as the stapling device needs only minimal mobilization of the bowel involved in the anastomosis. Restoring colorectal continuity after Hartmann's resection is a speedy, safe and simple procedure with the EEA (enteroenterostomy) stapler. Hartmann's operation may thus be considered the procedure of choice in emergency surgery for obstructed rectosigmoid cancer.

Use of a transanal drainage tube for prevention of anastomotic leakage and bleeding after anterior resection for rectal cancer.

PubMed

Zhao, Wen-Tao; Hu, Feng-Liang; Li, Yu-Ying; Li, Hong-Jie; Luo, Wei-Ming; Sun, Feng

2013-01-01

The aim of the present study was to investigate the usefulness of the transanal drainage tube for prevention of anastomotic leakage and bleeding after anterior resection for rectal cancer. Between January 2007 and May 2011 a nonrandomized prospective study of patients undergoing anterior resection for rectal cancer was done. The patients were divided into the transanal drainage tube (TDT) and non-transanal drainage tube (NTDT) groups according to whether the transanal drainage tube was used in the operation. Clinical characteristics and postoperative complications were compared between the TDT and NTDT groups. The study included 81 patients in the TDT group and 77 patients in the NTDT group. In the TDT group, anastomotic leakage occurred in 2 patients and no anastomotic bleeding occurred. In the NTDT group, anastomotic leakage occurred in 7 patients and anastomotic bleeding occurred in 2 patients. The TDT group had significantly fewer anastomotic complications compared with the NTDT group (2.5 vs 11.7 %; P = 0.029). Furthermore, the TDT group showed an obvious reduction in the rate of anastomotic leakage and anastomotic bleeding compared with the NTDT group (2.5 vs 7.8 % and 0.0 vs 2.6 %), but because the number of cases is relatively small, the difference did not reach statistical significance (P = 0.160 and P = 0.236). The use of a transanal drainage tube in anterior resection for rectal cancer may be a simple, safe, and effective means of preventing or reducing the occurrence of anastomotic leakage and bleeding. A larger-scale single or multi-center prospective randomized study or a meta-analysis including similar studies is necessary for further elucidation of this issue.

Combined abdominal and perineal approach for delayed restoration of bowel continuity after low anterior resection in females.

PubMed

Abou-Zeid, Ahmed A; Makki, Mahmoud T

2007-04-01

Restoration of bowel continuity after Hartmann's operation is the surgeon's goal and the patient's hope. This operation is technically demanding with reportedly high morbidity and mortality. A short distal rectal stump often makes the operation more difficult. In this article, we describe a combined abdominal and perineal approach, which can possibly make delayed restoration of bowel continuity after low anterior rectal resection an easier procedure.

[A Case of Pathological Complete Response after Neoadjuvant Chemotherapy(S-1 plus Oxaliplatin)and Laparoscopic Low Anterior Resection for Rectal Cancer].

PubMed

Ichinohe, Daichi; Morohashi, Hajime; Umetsu, Satoko; Yoshida, Tatsuya; Wakasa, Yusuke; Odagiri, Tadashi; Kimura, Toshirou; Suto, Akiko; Saito, Takeshi; Yoshida, Eri; Akasaka, Harue; Jin, Hiroyuki; Miura, Takuya; Sakamoto, Yoshiyuki; Hakamada, Kenichi

2016-11-01

We report a case of pathological complete response after neoadjuvant chemotherapy(NAC)(S-1 plus oxaliplatin)for rectal cancer. The patient was a 50-year-old man who had type 3 circumferential rectal cancer. An abdominal CT scan revealed locally advanced rectal cancer(cT3N2H0P0M0, cStage III b)with severe stenosis and oral-side intestinal dilatation. The patient was treated with NAC after loop-ileostomy. After 3 courses of chemotherapy, a CT scan revealed significant tumor reduction. Laparoscopic low anterior resection and bilateral lymph node dissection were performed 5 weeks after the last course of chemotherapy. The pathological diagnosis was a pathological complete response(no residual cancer cells). This case suggests that laparoscopic low anterior resection after NAC with S-1 plus oxaliplatin for locally advanced rectal cancer is a potentially effective procedure.

Successful embolization of a enterocutaneous fistula tract with Onyx 34 following low anterior resection for rectal cancer.

PubMed

Rahimi, Hamza; Venbrux, Anthony C; Obias, Vincent

2018-06-01

Enterocutaneous fistulas (ECFs) can be one of the complications found after surgical intervention for rectal cancer. Interventional modalities consisting of surgical, endoscopic, and radiological methods are often implemented to treat postoperative symptomatic complications. We present the case of 61-year-old Caucasian man who presented to us with a recent diagnosis of rectal cancer that had invaded the levators as well as anteriorly into the prostate, and who underwent low anterior resection with a diverting loop ileostomy. The patient was found to have a persistent presacral abscess due to an ECF tract. This case highlights the off-label use of ethylene-vinyl alcohol copolymer dissolved in dimethyl sulfoxide (Onyx 34) to seal an ECF.

Pott disease in the thoracolumbar spine with marked kyphosis and progressive paraplegia necessitating posterior vertebral column resection and anterior reconstruction with a cage.

PubMed

Pappou, Ioannis P; Papadopoulos, Elias C; Swanson, Andrew N; Mermer, Matthew J; Fantini, Gary A; Urban, Michael K; Russell, Linda; Cammisa, Frank P; Girardi, Federico P

2006-02-15

Case report. To report on a patient with Pott disease, progressive neurologic deficit, and severe kyphotic deformity, who had medical treatment fail and required posterior/anterior decompression with instrumented fusion. Treatment options will be discussed. Tuberculous spondylitis is an increasingly common disease worldwide, with an estimated prevalence of 800,000 cases. Surgical treatment consisting of extensive posterior decompression/instrumented fusion and 3-level posterior vertebral column resection, followed by anterior debridement/fusion with cage reconstruction. Neurologic improvement at 6-month follow-up (Frankel B to Frankel D), with evidence of radiographic fusion. A 70-year-old patient with progressive Pott paraplegia and severe kyphotic deformity, for whom medical treatment failed is presented. A posterior vertebral column resection, multiple level posterior decompression, and instrumented fusion, followed by an anterior interbody fusion with cage was used to decompress the spinal cord, restore sagittal alignment, and debride the infection. At 6-month follow-up, the patient obtained excellent pain relief, correction of deformity, elimination of the tuberculous foci, and significant recovery of neurologic function.

Anterior Spinal Reconstruction to the Clivus Using an Expandable Cage After C2 Chordoma Resection Via a Labiomandibular Glossotomy Approach: A Technical Report.

PubMed

Ozpinar, Alp; Liu, Jesse J; Whitney, Nathaniel L; Tempel, Zachary J; Choi, Philip A; Andersen, Peter E; Coppa, Nicholas D; Hamilton, D Kojo

2016-06-01

En bloc resection of high-cervical chordomas is a technically challenging procedure associated with significant morbidity. Two key components of this procedure include the approach and the method of spinal reconstruction. A limited number of reported cases of en bloc resection of high-cervical chordomas have been reported in the literature. We report a novel case using an expandable cage to reconstruct the anterior spinal column above C2 with fixation to the clivus. We also report a novel anterior approach to the high-cervical spine via a midline labiomandibular glossotomy. We detail the management of complications related to 2 instances of wound dehiscence and hardware exposure requiring two additional operations. The final surgical procedure involved explantation of the anterior cervical plate and use of a vascularized radial graft to close the posterior pharyngeal defect and protect the hardware. At 26-month follow-up, the patient remained disease free without any neurologic deficit. We report the novel use of the midline labiomandibular glossotomy for surgical approach and reconstruction of the anterior column to the clivus with an expandable cage. The unique features of this operative strategy allowed the surgical team to tailor the construct intraoperatively, resulting in solid arthrodesis without significant neurologic sequelae. Labiomandibular glossotomy for approach to high anterior cervical chordomas followed by craniospinal reconstruction to the clivus with an expandable cage represents a novel technique for managing high cervical chordomas. Copyright © 2016 Elsevier Inc. All rights reserved.

Impact of selective pituitary gland incision or resection on hormonal function after adenoma or cyst resection.

PubMed

Barkhoudarian, Garni; Cutler, Aaron R; Yost, Sam; Lobo, Bjorn; Eisenberg, Amalia; Kelly, Daniel F

2015-12-01

With the resection of pituitary lesions, the anterior pituitary gland often obstructs transsphenoidal access to the lesion. In such cases, a gland incision and/or partial gland resection may be required to obtain adequate exposure. We investigate this technique and determine the associated risk of post-operative hypopituitarism. All patients who underwent surgical resection of a pituitary adenoma or Rathke cleft cyst (RCC) between July 2007 and January 2013 were analyzed for pre- and post-operative hormone function. The cohort of patients with gland incision/resection were compared to a case-matched control cohort of pituitary surgery patients. Total hypophysectomy patients were excluded from outcome analysis. Of 372 operations over this period, an anterior pituitary gland incision or partial gland resection was performed in 79 cases (21.2 %). These include 53 gland incisions, 12 partial hemi-hypophysectomies and 14 resections of thinned/attenuated anterior gland. Diagnoses included 64 adenomas and 15 RCCs. New permanent hypopituitarism occurred in three patients (3.8 %), including permanent DI (3) and growth hormone deficiency (1). There was no significant difference in the rate of worsening gland dysfunction nor gain of function. Compared to a control cohort, there was a significantly lower incidence of transient DI (1.25 vs. 11.1 %, p = 0.009) but no significant difference in permanent DI (3.8 vs. 4.0 %) in the gland incision group. Selective gland incisions and gland resections were performed in over 20 % of our cases. This technique appears to minimize traction on compressed normal pituitary gland during removal of large lesions and facilitates better visualization and removal of cysts, microadenomas and macroadenomas.

Serotonin (5-HT3) receptor antagonists for the reduction of symptoms of low anterior resection syndrome

PubMed Central

Itagaki, Ryohei; Koda, Keiji; Yamazaki, Masato; Shuto, Kiyohiko; Kosugi, Chihiro; Hirano, Atsushi; Arimitsu, Hidehito; Shiragami, Risa; Yoshimura, Yukino; Suzuki, Masato

2014-01-01

Purpose Serotonin (5-hydroxytryptamine [5-HT])3 receptor antagonists are effective for the treatment of diarrhea-predominant irritable bowel syndrome (IBS-D), in which exaggerated intestinal/colonic hypermotility is often observed. Recent studies have suggested that the motility disorder, especially spastic hypermotility, seen in the neorectum following sphincter-preserving operations for rectal cancer may be the basis of the postoperative defecatory malfunction seen in these patients. We investigated the efficacy of 5-HT3 receptor antagonists in patients suffering from severe low anterior resection syndrome. Patients and methods A total of 25 male patients with complaints of uncontrollable urgency or fecal incontinence following sphincter-preserving operations were enrolled in this study. Defecatory status, assessed on the basis of incontinence score (0–20), urgency grade (0–3), and number of toilet visits per day, was evaluated using a questionnaire before and 1 month after the administration of the 5-HT3 antagonist ramosetron. Results All the parameters assessed improved significantly after taking ramosetron for 1 month. The effect was more prominent in cases whose anastomotic line was lower, ie, inside the anal canal. Defecatory function was better in patients who commenced ramosetron therapy within 6 months postoperatively, as compared to those who were not prescribed ramosetron for more than 7 months postoperatively. Conclusion These results suggest that 5-HT3 antagonists are effective for the treatment of low anterior resection syndrome, as in diarrhea-predominant irritable bowel syndrome. The improvement in symptoms is not merely time dependent, but it is related to treatment with 5-HT3 antagonists. PMID:24648748

Arousal Enhanced Memory Retention Is Eliminated Following Temporal Lobe Resection

ERIC Educational Resources Information Center

Ahs, Fredrik; Kumlien, Eva; Fredrikson, Mats

2010-01-01

The amygdala, situated in the anterior medial temporal lobe (MTL), is involved in the emotional enhancement of memory. The present study evaluated whether anterior MTL-resections attenuated arousal induced memory enhancement for pictures. Also, the effect of MTL-resections on response latencies at retrieval was assessed. Thirty-one patients with…

The effect of isolated labrum resection on shoulder stability.

PubMed

Pouliart, Nicole; Gagey, Olivier

2006-03-01

The present study was initiated to determine whether glenohumeral instability and dislocation can result from isolated lesions of the glenoid labrum in an arthroscopic cadaver model. Adjacent combinations of four zones of the labrum (superior, anterosuperior, anteroinferior and inferior) were sequentially removed with a motorised shaver, taking great care to leave the capsule intact in 24 cadaver shoulders. Stability was tested before and after inserting the scope and after each resection step. Inferior stability was examined by performing an inferior drawer test. Anterior stability was evaluated with an anteroposterior drawer test in 0 degrees of abduction and with a load-and-shift test in external rotation and 90 degrees abduction. Labral resection of all four zones maximally resulted in a grade 1 inferior instability (<10 mm inferior translation). When two adjacent labral zones were resected, a grade 2 anterior drawer (>10 mm anterior but no medial translation) was seen in 17% of the specimens. This was seen in one more specimen after the addition of a third zone. There were no differences in the stability of the load-and-shift test after any amount of labral resection. Total labral debridement increased inferior and anterior translation, but did not allow the humeral head to dislocate. The degree of stability in the cocked-arm position, which is the most prone to dislocation, is not altered. In patients, isolated labral tears, that is, without evidence of capsuloligamentous damage, can probably be safely debrided without risking glenohumeral instability to the point of dislocation. Nevertheless, anterior translation may significantly increase when two or more zones are resected.

[Application of three-stitch preventive transverse colostomy in anterior resection of low rectal cancer].

PubMed

Zhao, Yuzhou; Han, Guangsen; Huo, Mingke; Wei, Li; Zou, Qiyun; Zhang, Yuji; Li, Jian; Gu, Yanhui; Cao, Yanghui; Zhang, Shijia

2017-04-25

To explore the application of three-stitch preventive transverse colostomy in anterior resection of low rectal cancer. From May 2015 to March 2016, 70 consecutive low rectal cancer patients undergoing anterior resection and preventive transverse colostomy in our department were recruited in this prospective study. According to the random number table method, 70 patients were divided into three-stitch transverse colostomy group(observation group, n=35) and traditional transverse colostomy group(control group, n=35). Procedure of three-stitch preventive transverse colostomy was as follows: firstly, at the upper 1/3 incision 0.5-1.0 cm distance from the skin, 7# silk was used to suture from outside to inside, then the needle belt line went through the transverse edge of the mesangial avascular zone. At the lower 1/3 incision 0.5-1.0 cm distance from the skin, 7# silk was used to suture from inside to outside, then silk went through the transverse edge of the mesangial avascular zone again and was ligatured. Finally, in the upper and lower ends of the stoma, 7# silk was used to suture and fix transverse seromuscular layer and the skin. The operation time and morbidity of postoperative complications associated with colostomy were compared between two groups. There were no significant differences in baseline data between the two groups(all P>0.05). The operative time of observation group was shorter than that of control group [(3.2±1.3) min vs. (15.5±3.4) min, P<0.05]. Incidences of colostomy skin-mucous separation, dermatitis, stoma rebound were significantly lower in observation group [5.7%(2/35) vs. 34.3%(12/35), P=0.007; 8.6%(3/35) vs. 31.4%(11/35), P=0.036; 0 vs. 17.1%(6/35), P=0.025, respectively], while incidences of parastomal hernia and stoma prolapse in two groups were similar (both P>0.05). Compared with traditional transverse colostomy method, the three-stitch preventive transverse colostomy has more operating advantages and can reduce postoperative

TAMIS Assisted Laparoscopic Low Anterior Resection with Total Mesorectal Excision in a Cadaveric Series

PubMed Central

McLemore, Elisabeth C.; Coker, Alisa; Devaraj, Bikash; Chakedis, Jeffrey; Maawy, Ali; Inui, Tazo; Talamini, Mark A.; Horgan, Santiago; Peterson, Mike; Sylla, Patricia; Ramamoorthy, Sonia

2014-01-01

Background The purpose of this study is to demonstrate the feasibility of an innovative technique for the surgical management of rectal cancer: trans anal minimally invasive surgery assisted low anterior resection with total mesorectal excision (TAMIS assisted LAR TME) in a cadaver model. Trans anal endoscopic low anterior resection via natural orifice translumenal endoscopic surgery (NOTES) has been reported in cadaveric series using rigid trans anal endoscopic platforms. This procedure has not been described using a combination of a single incision laparoscopy and TAMIS soft trans anal endoscopic platform. Herein, we describe the first cadaveric series of TAMIS assisted single incision laparoscopic LAR with TME. Methods TAMIS assisted laparoscopic single incision LAR with TME was successfully performed in 5 fresh male human cadavers. The procedure was performed using the mini-Gelpoint single incision platform and the Gelpoint Path TAMIS platform (Applied Medical, Rancho Santa Margarita, CA). The variables recorded were age, body mass index (BMI in kg/m2), operative time, complications, and specimen length. The grade of the TME was determined by evaluation of the specimen by photo documentation by a gastrointestinal pathologist. Results All cadavers were male with a mean age of 71 +/− 8 years and mean BMI of 28 +/− 3 kg/m2. The mean operative time was 200 +/− 55 minutes (range 128 – 249 min). The quality of the TME was Grade I (complete) with intact mesorectum in all five cases. The mean specimen length was 36.8 +/− 3.4 cm. Intra-operative complications included one bowel injury and one splenic capsular tear. Conclusions TAMIS assisted laparoscopic LAR with TME is feasible in this pre-clinical cadaveric series. We have also demonstrated that a high quality TME can be achieved with this technique. Trans anal endoscopic techniques employed to perform total mesorectal dissection may revolutionize the surgical management of rectal cancer. However, phase II

Single-stage anterior high sacrectomy for locally recurrent rectal cancer.

PubMed

Fawaz, Khaled; Khaled, Fawaz; Smith, Myles J; Moises, Cukier; Smith, Andrew J; Yee, Albert J M

2014-03-01

A review of prospectively collected data on a consecutive series of patients undergoing single-stage anterior high sacrectomy for locally recurrent rectal carcinoma (LRRC). To determine the clinical outcome of patients who underwent anterior high sacrectomy for LRRC. High sacrectomy for oncological resection remains technically challenging. Surgery has the potential to achieve cure in carefully selected patients. Complete (R0) tumor excision in LRRC may require sacrectomy. High sacral resections (S3 and above) typically require a combined anterior/supine and posterior/prone procedure. We investigated our experience performing single-stage anterior high sacrectomy for LRRC. A consecutive series of patients with LRRC without systemic metastases who underwent resection with curative intent requiring high sacrectomy were identified. A review of a prospectively maintained colorectal and spine cancer database data was performed. An oblique dome high sacral osteotomy was performed during a single-stage anterior procedure. Outcome measures included surgical resection margin status, hospital length of stay, postoperative complications, physical functioning status, and overall survival. Nineteen consecutive patients were treated between 2002 and 2011. High sacrectomy was performed at sacral level S1-S2 in 4 patients, S2-S3 in 9 patients, and through S3 in 6 patients. An R0 resection margin was achieved histologically in all 19 cases. There was 1 early (<30 d) postoperative death (1/19, 5%). At median follow-up of 38 months, 13 patients had no evidence of residual disease, 1 was alive with disease, and 4 had died of disease. Morbidities occurred in 15 of the 19 patients (79%). Although high sacrectomy may require a combined anterior and posterior surgical approach, our series demonstrates the feasibility of performing single-stage anterior high sacrectomy in LRRC, with acceptable risks and outcomes compared with the literature. The procedure described by us for LRRC lessens

Bowel symptoms and self-care strategies of survivors in the process of restoration after low anterior resection of rectal cancer.

PubMed

Yin, Lishi; Fan, Ling; Tan, Renfu; Yang, Guangjing; Jiang, Fenglin; Zhang, Chao; Ma, Jun; Yan, Yang; Zou, Yanhong; Zhang, Yaowen; Wang, Yamei; Zhang, Guifang

2018-06-04

The purpose of this research is to identify the bowel symptoms and self-care strategies for rectal cancer survivors during the recovery process following low anterior resection surgery. A total of 100 participants were investigated under the structured interview guide based on the dimensions of "symptom management theory". 92% of participants reported changes in bowel habits, the most common being the frequent bowel movements and narrower stools, which we named it finger-shaped consistency stools. The 6 most frequently reported bowel symptoms were excessive flatus (93%), clustering (86%), urgency (77%), straining (62%), bowel frequency (57%) and anal pendant expansion (53%). Periodic bowel movements occurred in 19% participants. For a group of 79 participants at 6 to 24 months post-operation, 86.1% reported a significant improvement of bowel symptoms. Among 68 participants of this subgroup with significant improvements, 70.5% participants reported the length of time it took was at least 6 months. Self-care strategies adopted by participants included diet, bowel medications, practice management and exercise. It is necessary to educate patients on the symptoms experienced following low anterior resection surgery. Through the process of trial and error, participants have acquired self-care strategies. Healthcare professionals should learn knowledge of such strategies and help them build effective interventions.

Perineal pseudocontinent colostomy for ultra-low rectal adenocarcinoma: the muscular graft as a pseudosphincter.

PubMed

Souadka, Amine; Majbar, Mohammed Anass; Amrani, Laila; Souadka, Abdelilah

2016-10-01

The aim of this study was to analyze objectively the role of the muscular graft in the continence using manometric study in the patients who underwent pseudocontinent perineal colostomy after abdominoperineal resection for rectal adenocarcinoma. This was a retrospective study including all the patients from January 2002 to December 2009 who underwent an abdominoperineal resection followed by perineal pseudocontinent colostomy for ultra-low rectal adenocarcinoma and agreed to perform the manometric evaluation of the muscular graft. Fifteen patients were included, six males and nine females, with a mean age of 50 years. According to Kirwan's classification, 2 (13.3%) patients had normal continence (Stage A) had 10 (66.6%) no soiling (stage B) and 3 (20%) patients had minimal soiling (Stage C). The manometric evaluation was performed after a median period of 12 months post-surgery. The mean maximal resting and squeeze pressures were respectively 41 cmH2O and 59 cmH2O and the mean colonic sensory volume was 12 ml. This study showed that the musculae graft of Pseudocontinent Perineal colostomy acted as a hypotonic sphincter that pressure can increase during the voluntary squeeze. These data may help to clarify the functional outcomes of this technique after APR for ultra-low rectal adenocarcinoma.

Pure laparoscopic hepatectomy in semiprone position for right hepatic major resection.

PubMed

Ikeda, Tetsuo; Mano, Yohei; Morita, Kazutoyo; Hashimoto, Naotaka; Kayashima, Hirohito; Masuda, Atsuro; Ikegami, Toru; Yoshizumi, Tomoharu; Shirabe, Ken; Maehara, Yoshihiko

2013-02-01

Pure laparoscopic liver resection is technically difficult for tumors located in the dorsal anterior and posterior sectors. We have developed a maneuver to perform pure laparoscopic hepatectomy in the semiprone position which was developed for resecting tumors located in these areas. The medical records have been reviewed retrospectively in 30 patients who underwent laparoscopic liver resection in the semiprone position for carcinoma in the dorsal anterior or posterior sectors of the right liver between 2008 and 2011. Seventeen liver tumors were primary liver tumors and 13 were colorectal metastases. Of the 30 patients, 11 (36.6 %) underwent major hepatectomy [right hemihepatectomy in 7 (23.3 %) and posterior sectionectomy in 4 (13.3 %)]. Anatomical minor resection, such as S6 or S7 segmentectomy, was performed in five patients (16.6 %). Five patients with liver metastasis underwent a simultaneous laparoscopic resection. There was no mortality, reoperation, or conversion to open procedures. There were no hepatectomy-related complications such as postoperative bleeding, bile leakage, or liver failure. Pure laparoscopic hepatectomy in the semiprone position for tumors present in the dorsal anterior and posterior sectors is feasible and safe. This method expands the indications for laparoscopic liver resection for tumors.

The effect of anterior longitudinal ligament resection on lordosis correction during minimally invasive lateral lumbar interbody fusion: Biomechanical and radiographic feasibility of an integrated spacer/plate interbody reconstruction device.

PubMed

Kim, Choll; Harris, Jonathan A; Muzumdar, Aditya; Khalil, Saif; Sclafani, Joseph A; Raiszadeh, Kamshad; Bucklen, Brandon S

2017-03-01

Lateral lumbar interbody fusion is powerful for correcting degenerative conditions, yet sagittal correction remains limited by anterior longitudinal ligament tethering. Although lordosis has been restored via ligament release, biomechanical consequences remain unknown. Investigators examined radiographic and biomechanical of ligament release for restoration of lumbar lordosis. Six fresh-frozen human cadaveric spines (L3-S1) were tested: (Miller et al., 1988) intact; (Battie et al., 1995) 8mm spacer with intact anterior longitudinal ligament; (Cho et al., 2013) 8mm spacer without intact ligament following ligament resection; (Galbusera et al., 2013) 13mm lateral lumbar interbody fusion; (Goldstein et al., 2001) integrated 13mm spacer. Focal lordosis and range of motion were assessed by applying pure moments in flexion-extension, lateral bending, and axial rotation. Cadaveric radiographs showed significant improvement in lordosis correction following ligament resection (P<0.05). The 8mm spacer with ligament construct provided greatest stability relative to intact (P>0.05) but did little to restore lordosis. Ligament release significantly destabilized the spine relative to intact in all modes and 8mm with ligament in lateral bending and axial rotation (P<0.05). Integrated lateral lumbar interbody fusion following ligament resection did not significantly differ from intact or from 8mm with ligament in all testing modes (P>0.05). Lordosis corrected by lateral lumbar interbody fusion can be improved by anterior longitudinal ligament resection, but significant construct instability and potential implant migration/dislodgment may result. This study shows that an added integrated lateral fixation system can significantly improve construct stability. Long-term multicenter studies are needed. Copyright © 2017 Elsevier Ltd. All rights reserved.

Changes in the rotational axes of the tibiofemoral joint caused by resection of the anterior cruciate ligament.

PubMed

Bonny, Daniel P; Howell, Stephen M; Hull, Maury L

2017-04-01

Kinematic alignment is a method of aligning implants in total knee arthroplasty (TKA) that strives to restore the native flexion-extension (F-E) and longitudinal rotation (LR) axes of the tibiofemoral joint. The anterior cruciate ligament (ACL) is typically resected at the time of TKA, which might change the position, and orientation of these axes from that of the native knee. Our objective was to determine whether resecting the ACL causes changes in the F-E and LR axes. A custom designed and validated instrumented spatial linkage (ISL) measured the F-E and LR axes in nine cadaveric knees before and after ACL resection. Changes in these axes were computed for knee flexion from 0° to 120°. For the F-E axis, the two statistically significant yet relatively small changes were internal rotation of 0.5° (p = 0.02) and posterior translation of 0.3 mm (p = 0.04). For the LR axis, the statistically significant and relatively large change was medial translation of 2.1 mm (p = 0.01). Changes to the LR axis in both medial-lateral position and varus-valgus orientation varied widely; 77% of a population of knees would have a medial-lateral position change greater than 1 mm, and 53% of a population of knees would have a varus-valgus orientation change greater than 1°. Knowledge of changes of the F-E and LR axes caused by resecting the ACL provides an important baseline for determining the changes in these axes caused by kinematic alignment and mechanical alignment of bi-cruciate retaining, posterior cruciate retaining, and posterior cruciate substituting implants. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 35:886-893, 2017. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

The novel appearance of low rectal anastomosis on contrast enema following laparoscopic anterior resection: discriminating anastomotic leaks from "dog-ears" on water-soluble contrast enema and flexible sigmoidoscopy.

PubMed

Katory, Mark; McLean, Ross; Osman, Khalid; Ahmad, Mukhtar; Hughes, Tracey; Newby, Mike; Dennison, Christopher; O'Loughlin, Paul

2017-02-01

Interpretation of water-soluble contrast enema following laparoscopic low anterior resection can be very challenging for both radiologists and colorectal surgeons. Discriminating the radiological appearances secondary to anastomotic configuration from those caused by actual anastomotic dehiscence is a common problem and may be made worse with the advent of laparoscopic surgery. The aim of this study is to identify potential novel appearances of the water-soluble contrast enema (WSCE) images of rectal anastomosis following laparoscopic low anterior resection to radiologists and surgeons. We enrolled 45 patients who underwent laparoscopic low anterior resection with proximal de-functioning loop ileostomy within a specialized colorectal unit. The water-soluble contrast enema reports were reviewed. Two blinded colorectal radiologists independently reviewed the images of patients suspected of anastomotic leak. All of these patients also underwent a flexible sigmoidoscopy to confirm or exclude anastomotic leak before reversal of loop ileostomy. Inter-observer concordance was calculated. Seven out of eighteen patients (38.9%) were found to have true anastomotic leaks on flexible sigmoidoscopy (15% overall leak rate). In the remaining eleven patients the image appearances were attributed to the appearance of the anastomotic 'dog-ear effect', created by the anastomotic configuration due to multiple firing of the intra-corporeal laparoscopic stapling device. Radiologist inter-observer concordance was 83%. Sensitivity was 100%, specificity 71%, positive-predictive value (38.9%) and negative-predictive value (100%). The novel appearances of laparoscopic-stapled rectal anastomoses in WSCE can be mistaken for anastomotic leak. To avoid delay in reversal of ileostomy, a flexible sigmoidoscopy can be used to confirm or exclude a leak.

Impaired familiarity with preserved recollection after anterior temporal-lobe resection that spares the hippocampus.

PubMed

Bowles, Ben; Crupi, Carina; Mirsattari, Seyed M; Pigott, Susan E; Parrent, Andrew G; Pruessner, Jens C; Yonelinas, Andrew P; Köhler, Stefan

2007-10-09

It is well established that the medial-temporal lobe (MTL) is critical for recognition memory. The MTL is known to be composed of distinct structures that are organized in a hierarchical manner. At present, it remains controversial whether lower structures in this hierarchy, such as perirhinal cortex, support memory functions that are distinct from those of higher structures, in particular the hippocampus. Perirhinal cortex has been proposed to play a specific role in the assessment of familiarity during recognition, which can be distinguished from the selective contributions of the hippocampus to the recollection of episodic detail. Some researchers have argued, however, that the distinction between familiarity and recollection cannot capture functional specialization within the MTL and have proposed single-process accounts. Evidence supporting the dual-process view comes from demonstrations that selective hippocampal damage can produce isolated recollection impairments. It is unclear, however, whether temporal-lobe lesions that spare the hippocampus can produce selective familiarity impairments. Without this demonstration, single-process accounts cannot be ruled out. We examined recognition memory in NB, an individual who underwent surgical resection of left anterior temporal-lobe structures for treatment of intractable epilepsy. Her resection included a large portion of perirhinal cortex but spared the hippocampus. The results of four experiments based on three different experimental procedures (remember-know paradigm, receiver operating characteristics, and response-deadline procedure) indicate that NB exhibits impaired familiarity with preserved recollection. The present findings thus provide a crucial missing piece of support for functional specialization in the MTL.

Is early detection of anastomotic leakage possible by intraperitoneal microdialysis and intraperitoneal cytokines after anterior resection of the rectum for cancer?

PubMed

Matthiessen, Peter; Strand, Ida; Jansson, Kjell; Törnquist, Cathrine; Andersson, Magnus; Rutegård, Jörgen; Norgren, Lars

2007-11-01

This prospective study assessed methods of detecting intraperitoneal ischemia and inflammatory response in patients with and without postoperative complications after anterior resection of the rectum. In 23 patients operated on with anterior resection of the rectum for rectal carcinoma, intraperitoneal lactate, pyruvate, and glucose levels were monitored postoperatively for six days by using microdialysis with catheters applied in two locations: intraperitoneally near the anastomosis, and in the central abdominal cavity. A reference catheter was placed subcutaneously in the pectoral region. Cytokines, interleukin (IL)-6, IL-10, and tumor necrosis factor (TNF)-alpha, were measured in intraperitoneal fluid by means of a pelvic drain for two postoperative days. The intraperitoneal lactate/pyruvate ratio near the anastomosis was higher on postoperative Day 5 (P = 0.029) and Day 6 (P = 0.009) in patients with clinical anastomotic leakage (n = 7) compared with patients without leakage (n = 16). The intraperitoneal levels of IL-6 (P = 0.002; P = 0.012, respectively) and IL-10 (P = 0.002; P = 0.041, respectively) were higher on postoperative Days 1 and 2 in the leakage group, and TNF-alpha was higher in the leakage group on Day 1 (P = 0.011). In-hospital clinical anastomotic leakage was diagnosed on median Day 6, and leakage after hospital discharge on median Day 20. The intraperitoneal lactate/pyruvate ratio and cytokines, IL-6, IL-10, and TNF-alpha, were increased in patients who developed symptomatic anastomotic leakage before clinical symptoms were evident.

Dutch validation of the low anterior resection syndrome score.

PubMed

Hupkens, B J P; Breukink, S O; Olde Reuver Of Briel, C; Tanis, P J; de Noo, M E; van Duijvendijk, P; van Westreenen, H L; Dekker, J W T; Chen, T Y T; Juul, T

2018-04-21

The aim of this study was to validate the Dutch translation of the low anterior resection syndrome (LARS) score in a population of Dutch rectal cancer patients. Patients who underwent surgery for rectal cancer received the LARS score questionnaire, a single quality of life (QoL) category question and the European Organization for Research and Treatment of Cancer (EORTC) QLQ-C30 questionnaire. A subgroup of patients received the LARS score twice to assess the test-retest reliability. A total of 165 patients were included in the analysis, identified in six Dutch centres. The response rate was 62.0%. The percentage of patients who reported 'major LARS' was 59.4%. There was a high proportion of patients with a perfect or moderate fit between the QoL category question and the LARS score, showing a good convergent validity. The LARS score was able to discriminate between patients with or without neoadjuvant radiotherapy (P = 0.003), between total and partial mesorectal excision (P = 0.008) and between age groups (P = 0.039). There was a statistically significant association between a higher LARS score and an impaired function on the global QoL subscale and the physical, role, emotional and social functioning subscales of the EORTC QLQ-C30 questionnaire. The test-retest reliability of the LARS score was good, with an interclass correlation coefficient of 0.79. The good psychometric properties of the Dutch version of the LARS score are comparable overall to the earlier validations in other countries. Therefore, the Dutch translation can be considered to be a valid tool for assessing LARS in Dutch rectal cancer patients. Colorectal Disease © 2018 The Association of Coloproctology of Great Britain and Ireland.

Early detection of anastomotic leakage after elective low anterior resection.

PubMed

Fouda, Elyamani; El Nakeeb, Ayman; Magdy, Alaa; Hammad, Enas A; Othman, Gamal; Farid, Mohamed

2011-01-01

Colorectal anastomotic leakage is a serious complication leading to major postoperative morbidity and mortality. In the present study, we investigated the early detection of anastomotic leakage before its clinical presentation. Fifty-six patients with rectal cancer were included prospectively in this study. All patients underwent elective low anterior resection. Peritoneal samples were collected from the abdominal drains at the first, third, and fifth days postoperatively for bacteriological study (quantitative cultures for both aerobes and anaerobes) and cytokines (IL-6, IL-10, TNF) measurement. Patients were divided into two groups: those without symptomatic or clinical evidence of anastomotic leakage (AL; group 1) and those with clinical evidence of AL (group 2). Study variables included hospital stay, wound infection, operative time, blood loss, height of anastomosis, intraperitoneal cytokines, and microbiological study of peritoneal fluid. Clinically evident AL occurred in eight patients (14.3%) and diagnosed postoperatively on median day 6. Intraperitoneal bacterial colonization and cytokine levels were significantly higher in patients with clinical evidence of AL. Wound infection was significantly higher in anastomotic leakage group. The hospital stay for the patients with anastomotic leakage was significantly longer than those without AL (14 ± 1.41 vs. 5.43 ± 0.89 days). A significant difference among two groups was observed regarding operative time, blood loss, blood transfusion, and height of the anastomosis. The peritoneal cytokines levels and intraperitoneal bacterial colonization might be an additional diagnostic tool that can support the decision making of surgeons for early detection of anastomotic leak in colorectal surgery.

Endoscopic craniofacial resection. Indications and technical aspects.

PubMed

Llorente, José Luis; López, Fernando; Suárez, Vanessa; Costales, María; Moreno, Carla; Suárez, Carlos

2012-01-01

Anterior craniofacial resection (CFR) is a standardised procedure for the treatment of tumours involving the anterior skull base. We present our experience in the endoscopic treatment of these tumours. A retrospective analysis was performed of patients treated by endoscopic anterior CFR in our Department from 2004 until 2011. Thirty-two patients were analysed. Mean follow-up was 28 months (range: 6-84 months). The most frequent pathological entity was adenocarcinoma (60%), followed by undifferentiated carcinoma (13%). According to TNM classification, malignant epithelial tumour staging was T3 in 9%, T4a in 53% and T4b in 19% of the malignant epithelial tumours. The complication rate was 6% and the resection was complete in 91% of cases. During follow-up, 9% of patients developed recurrence. The 5-year overall survival rate was 70% and the 5-year disease-free survival rate was 85% These results seem to indicate that properly planned endoscopic CFR may be a valid alternative to traditional open approaches for the management of malignancies of the anterior skull base. Copyright © 2012 Elsevier España, S.L. All rights reserved.

Management of Chest Drains After Thoracic Resections.

PubMed

Filosso, Pier Luigi; Sandri, Alberto; Guerrera, Francesco; Roffinella, Matteo; Bora, Giulia; Solidoro, Paolo

2017-02-01

Immediately after lung resection, air tends to collect in the retrosternal part of the chest wall (in supine position), and fluids in its lower part (costodiaphragmatic sinus). Several general thoracic surgery textbooks currently recommend the placement of 2 chest tubes after major pulmonary resections, one anteriorly, to remove air, and another into the posterior and basilar region, to drain fluids. Recently, several authors advocated the placement of a single chest tube. In terms of air and fluid drainage, this technique demonstrated to be as effective as the conventional one after wedge resection or uncomplicated lobectomy. Copyright © 2016 Elsevier Inc. All rights reserved.

Perihilar Glissonian Approach for Anatomical Parenchymal Sparing Liver Resections: Technical Aspects: The Taping Game.

PubMed

Figueroa, Rodrigo; Laurenzi, Andrea; Laurent, Alexis; Cherqui, Daniel

2018-03-01

To present technical details for central hepatectomy and right anterior and posterior sectionectomies using perihilar Glissonian approach for anatomical delineation and selective inflow occlusion. Central tumors and those deeply located in the right liver may require extensive resections because of their proximity to major vascular structures. In such cases, anatomical more limited resections such as central hepatectomy or sectionectomies may provide an alternative to extensive surgery by assuring both parenchymal sparing and suitable oncologic resection. We present the global concept for performing a perihilar Glissonian approach and its application to each individual anatomical procedure. This includes detailed descriptions, illustrations, and videos demonstrating the technique. This technique was applied since 1991 for anatomical parenchymal resections including central hepatectomy (resection of segments 4, 5, and 8), right anterior sectionectomy (resection of segments 5 and 8), and right posterior sectionectomy (resection of segments 6 and 7). The feasibility rate of the Glissonian approach was 88%. Perihilar Glissonian approach is a safe and reproducible technique that enables anatomical parenchymal preserving liver resections for selected central and right-sided deeply located tumors.

[Trans-suture mechanical colorectal anastomosis using a double stapler in the anterior resection of the rectum. Technical note].

PubMed

Saviano, M S; Ricchi, E

1990-04-30

The spread of mechanical staplers now makes it possible to perform anastomoses in anterior resections of the rectum that are easier and safer than manual ones. Certain related problems are well known, particularly in patients with narrow pelvis and, in low anastomoses, the fashioning of the tobacco pouch on the distal rectal stump. The technique of transutural mechanical colorectal anastomosis with circular stapler after closure of the rectal stump with linear stapler is described in detail. Advantages of the technique are: anastomoses that are technically easier and safer because making of the tobacco pouch on the distal rectal stump is avoided; pollution of the operating field is reduced to the minimum; there are no problems related to differences in lumen of the colorectal stumps.

A case of laparoscopic high anterior resection of rectosigmoid colon cancer associated with a horseshoe kidney using preoperative 3D-CT angiography.

PubMed

Kubo, Naoki; Furusawa, Norihiko; Imai, Shinichiro; Terada, Masaru

2018-06-27

Horseshoe kidney is a congenital malformation in which the bilateral kidneys are fused. It is frequently complicated by other congenital malformations and is often accompanied by anomalies of the ureteropelvic and vascular systems, which must be evaluated to avoid iatrogenic injury. We report a case of laparoscopic high anterior resection of rectosigmoid colon cancer associated with a horseshoe kidney using preoperative 3D-CT angiography. A 52-year-old Japanese man with lower abdominal pain underwent lower endoscopy, revealing a type 2 lesion in the rectosigmoid colon. He was diagnosed with rectosigmoid colon cancer with multiple lung metastases and a horseshoe kidney on computed tomography (CT) scan. Three-dimensional (3D)-CT angiography showed an aberrant renal artery at the isthmus from 3 cm under the inferior mesenteric artery (IMA) branch of the aorta. Laparoscopic anterior rectal resection was performed. During the operation, the inferior mesenteric artery, left ureter, left gonadal vessels, and hypogastric nerve plexus could be seen passing over the horseshoe kidney isthmus and were preserved. The left branch of aberrant renal artery that was close to IMA was also detected and preserved. To prevent intraoperative misidentification, 3D-CT angiography should be performed preoperatively to ascertain the precise positional relationships between the extra renal arteries and the kidney. We always must consider anomalous locations of renal vessels, ureter, gonadal vessels, and lumbar splanchnic nerve to avoid laparoscopic iatrogenic injury in patients with a horseshoe kidney.

A new improved technique for placement of a pursestring suture on the edge of the distal part of the rectal stump using a skin stapler for low anterior resection.

PubMed

Kumashiro, R; Sano, C; Ugaeri, H; Madokoro, S; Maekawa, T; Kumamoto, M; Hideshima, T; Inutsuka, S

1994-04-01

Instead of a linear stapler or manual pursestring suture onto the lower part of the rectum, we placed a No. 2-0 Prolene suture on the edge of the rectal stump, using 12 to 16 clips and a disposable skin stapler. This technique is satisfactory for very low anterior resection.

Laparoscopic Double Discoid Resection With a Circular Stapler for Bowel Endometriosis.

PubMed

Kondo, William; Ribeiro, Reitan; Zomer, Monica Tessmann; Hayashi, Renata

2015-01-01

To demonstrate the technique of laparoscopic double discoid resection with a circular stapler for bowel endometriosis. Case report (Canadian Task Force classification III). Private hospital in Curitiba, Paraná, Brazil. A 33-year-old woman was referred to our service complaining about cyclic dysmenorrhea, dyspareunia, chronic pelvic pain, and cyclic dyschezia. Transvaginal ultrasound with bowel preparation showed a 6-cm endometriotic nodule at the retrocervical area, uterosacral ligaments, posterior vaginal fornix, and anterior rectal wall, infiltrating up to the submucosa, 5 cm far from the anal verge. Under general anesthesia, the patient was placed in the dorsal decubitus position with her arms alongside her body and her lower limbs in abduction. Pneumoperitoneum was achieved using a Veres needle placed at the umbilicus. Four trocars were placed: a 10-mm trocar at the umbilicus for the zero-degree laparoscope; a 5-mm trocar at the right anterosuperior iliac spine; a 5-mm trocar in the midline between the umbilicus and the pubic symphysis, approximately 8 to 10 cm inferior to the umbilical trocar; and a 5-mm trocar at the left anterosuperior iliac spine. The entire pelvis was inspected for endometriotic lesions, and all implants in the anterior compartment of the pelvis were resected. The lesions located at the ovarian fossae were completely removed. The ureters were identified bilaterally, and both para-rectal fossae were dissected. The right hypogastric nerve was released from the disease laterally. The lesion was separated from the retrocervical area, and the posterior vaginal fornix was resected (reverse technique), leaving the disease attached to the anterior surface of the rectum. The lesion was shaved off the anterior rectal wall using a harmonic scalpel. A x-shaped stitch was placed at the anterior rectal wall using 2-0 mononylon suture. A 33-mm circular stapler was placed transanally under laparoscopic control, and once it reached the area to be resected

Multicenter study of outcome in relation to the type of resection in rectal cancer.

PubMed

Ortiz, Hector; Wibe, Arne; Ciga, Miguel Angel; Kreisler, Esther; Garcia-Granero, Eduardo; Roig, Jose Vicente; Biondo, Sebastiano

2014-07-01

A surgical teaching and auditing program has been implemented to improve the results of treatment for patients with rectal cancer. The aim of this study was to assess the treatment and outcome in patients resected for rectal cancer, focusing on differences relating to the type of resection. This was an observational study. The study took place throughout the network of hospitals that compose the National Health Service in Spain. This study included a consecutive cohort of 3355 patients from the Spanish Rectal Cancer Project. The data of patients who were operated on electively, with curative intent, by anterior resection (n = 2333 [69.5%]), abdominoperineal excision (n = 774 [23.1%]), and Hartmann procedure (n = 248 [7.4%]) between March 2006 and May 2010 were analyzed. Clinical, pathologic, and outcome results were analyzed in relation to the type of surgery performed. After a median follow-up time of 37 months (interquartile range, 30-48 months), bowel perforations were found to be more common in the Hartmann procedure (12.6%) and abdominoperineal groups (10.1%) than in the anterior resection group (2.3%; p < 0.001). Involvement of the circumferential resection margin was also more common in the Hartmann (16.6%) and abdominoperineal groups (14.3%) than in the anterior resection group (6.6%; p < 0.001). Multivariate analysis showed a negative influence on local recurrence, metastasis, survival for advanced stage, intraoperative perforation, invaded circumferential margin, and Hartmann procedure. However, abdominoperineal excision did not significantly influence local recurrence (HR, 0.945; 95% CI, 0.571-1.563; p = 0.825). The main weakness of this study was the voluntary nature of registration in the Spanish Rectal Cancer Project. Although bowel perforation and involvement of the circumferential resection margin were more common after abdominoperineal excision than after anterior resection, this study did not identify abdominoperineal excision as a determinant of

Risk factors of stoma re-creation after closure of diverting ileostomy in patients with rectal cancer who underwent low anterior resection or intersphincteric resection with loop ileostomy.

PubMed

Song, Ook; Kim, Kyung Hwan; Lee, Soo Young; Kim, Chang Hyun; Kim, Young Jin; Kim, Hyeong Rok

2018-04-01

The aim of this study was to identify the risk factors of stoma re-creation after closure of diverting ileostomy in patients with rectal cancer who underwent low anterior resection (LAR) or intersphincteric resection (ISR) with loop ileostomy. We retrospectively reviewed 520 consecutive patients with rectal cancer who underwent LAR or ISR with loop ileostomy from January 2005 to December 2014 at Chonnam National University Hwasun Hospital. Risk factors for stoma re-creation after ileostomy closure were evaluated. Among 520 patients with rectal cancer who underwent LAR or ISR with loop ileostomy, 458 patients underwent stoma closure. Among these patients, 45 (9.8%) underwent stoma re-creation. The median period between primary surgery and stoma closure was 5.5 months (range, 0.5-78.3 months), and the median period between closure and re-creation was 6.8 months (range, 0-71.5 months). Stoma re-creation was performed because of anastomosis-related complications (26, 57.8%), local recurrence (15, 33.3%), and anal sphincter dysfunction (3, 6.7%). Multivariate analysis showed that independent risk factors for stoma re-creation were anastomotic leakage (odds ratio [OR], 4.258; 95% confidence interval [CI], 1.814-9.993), postoperative radiotherapy (OR, 3.947; 95% CI, 1.624-9.594), and ISR (OR, 3.293; 95% CI, 1.462-7.417). Anastomotic leakage, postoperative radiotherapy, and ISR were independent risk factors for stoma re-creation after closure of ileostomy in patients with rectal cancer.

A worldwide comparison of the management of T1 and T2 anterior floor of the mouth and tongue squamous cell carcinoma - Extent of surgical resection and reconstructive measures.

PubMed

Kansy, Katinka; Mueller, Andreas Albert; Mücke, Thomas; Koersgen, Friederike; Wolff, Klaus Dietrich; Zeilhofer, Hans-Florian; Hölzle, Frank; Pradel, Winnie; Schneider, Matthias; Kolk, Andreas; Smeets, Ralf; Acero, Julio; Haers, Piet; Ghali, G E; Hoffmann, Jürgen

2017-12-01

Microvascular surgery following tumor resection has become an important field of oral maxillofacial surgery (OMFS). Following the results on general aspects of current reconstructive practice in German-speaking countries, Europe and worldwide, this paper presents specific concepts for the management of resection and reconstruction of T1/T2 squamous cell carcinoma (SCC) of the anterior floor of the mouth and tongue. The DOESAK questionnaire was distributed in three different phases to a growing number of maxillofacial units worldwide. Within this survey, clinical patient settings were presented to participants and center-specific treatment strategies were evaluated. A total of 188 OMFS units from 36 different countries documented their treatment strategies for T1/T2 anterior floor of the mouth squamous cell carcinoma and tongue carcinoma. For floor of mouth carcinoma close to the mandible, a wide variety of concepts are presented: subperiosteal removal of the tumor versus continuity resection of the mandible and reconstruction ranging from locoregional closure to microvascular bony reconstruction. For T2 tongue carcinoma, concepts are more uniform. These results demonstrate the lack of evidence and the controversy of different guidelines for the extent of safety margins and underline the crucial need of global prospective randomized trials on this topic to finally obtain evidence for a common guideline based on a strong community of OMFS units. Copyright © 2017 European Association for Cranio-Maxillo-Facial Surgery. All rights reserved.

Ultralow Noise Monolithic Quantum Dot Photonic Oscillators

DTIC Science & Technology

2013-10-28

HBCU/MI) ULTRALOW NOISE MONOLITHIC QUANTUM DOT PHOTONIC OSCILLATORS LUKE LESTER UNIVERSITY OF NEW MEXICO 10/28/2013 Final Report DISTRIBUTION A...TELEPHONE NUMBER (Include area code) 24-10-2013 Final 01-06-2010 to 31-05-2013 Ultralow Noise Monolithic Quantum Dot Photonic Oscillators FA9550-10-1-0276...277-7647 Reset Grant Title: ULTRALOW NOISE MONOLITHIC QUANTUM DOT PHOTONIC OSCILLATORS Grant/Contract Number: FA9550-10-1-0276 Final Performance

Awake craniotomy for tumor resection.

PubMed

Attari, Mohammadali; Salimi, Sohrab

2013-01-01

Surgical treatment of brain tumors, especially those located in the eloquent areas such as anterior temporal, frontal lobes, language, memory areas, and near the motor cortex causes high risk of eloquent impairment. Awake craniotomy displays major rule for maximum resection of the tumor with minimum functional impairment of the Central Nervous System. These case reports discuss the use of awake craniotomy during the brain surgery in Alzahra Hospital, Isfahan, Iran. A 56-year-old woman with left-sided body hypoesthesia since last 3 months and a 25-year-old with severe headache of 1 month duration were operated under craniotomy for brain tumors resection. An awake craniotomy was planned to allow maximum tumor intraoperative testing for resection and neurologic morbidity avoidance. The method of anesthesia should offer sufficient analgesia, hemodynamic stability, sedation, respiratory function, and also awake and cooperative patient for different neurological test. Airway management is the most important part of anesthesia during awake craniotomy. Tumor surgery with awake craniotomy is a safe technique that allows maximal resection of lesions in close relationship to eloquent cortex and has a low risk of neurological deficit.

Awake craniotomy for tumor resection

PubMed Central

Attari, Mohammadali; Salimi, Sohrab

2013-01-01

Surgical treatment of brain tumors, especially those located in the eloquent areas such as anterior temporal, frontal lobes, language, memory areas, and near the motor cortex causes high risk of eloquent impairment. Awake craniotomy displays major rule for maximum resection of the tumor with minimum functional impairment of the Central Nervous System. These case reports discuss the use of awake craniotomy during the brain surgery in Alzahra Hospital, Isfahan, Iran. A 56-year-old woman with left-sided body hypoesthesia since last 3 months and a 25-year-old with severe headache of 1 month duration were operated under craniotomy for brain tumors resection. An awake craniotomy was planned to allow maximum tumor intraoperative testing for resection and neurologic morbidity avoidance. The method of anesthesia should offer sufficient analgesia, hemodynamic stability, sedation, respiratory function, and also awake and cooperative patient for different neurological test. Airway management is the most important part of anesthesia during awake craniotomy. Tumor surgery with awake craniotomy is a safe technique that allows maximal resection of lesions in close relationship to eloquent cortex and has a low risk of neurological deficit. PMID:24223378

Revealing the Dynamic Modulations That Underpin a Resilient Neural Network for Semantic Cognition: An fMRI Investigation in Patients With Anterior Temporal Lobe Resection.

PubMed

Rice, Grace E; Caswell, Helen; Moore, Perry; Lambon Ralph, Matthew A; Hoffman, Paul

2018-06-06

One critical feature of any well-engineered system is its resilience to perturbation and minor damage. The purpose of the current study was to investigate how resilience is achieved in higher cognitive systems, which we explored through the domain of semantic cognition. Convergent evidence implicates the bilateral anterior temporal lobes (ATLs) as a conceptual knowledge hub. While bilateral damage to this region produces profound semantic impairment, unilateral atrophy/resection or transient perturbation has a limited effect. Two neural mechanisms might underpin this resilience to unilateral ATL damage: 1) the undamaged ATL upregulates its activation in order to compensate; and/or 2) prefrontal regions involved in control of semantic retrieval upregulate to compensate for the impoverished semantic representations that follow from ATL damage. To test these possibilities, 34 postsurgical temporal lobe epilepsy patients and 20 age-matched controls were scanned whilst completing semantic tasks. Pictorial tasks, which produced bilateral frontal and temporal activation, showed few activation differences between patients and control participants. Written word tasks, however, produced a left-lateralized activation pattern and greater differences between the groups. Patients with right ATL resection increased activation in left inferior frontal gyrus (IFG). Patients with left ATL resection upregulated both the right ATL and right IFG. Consistent with recent computational models, these results indicate that 1) written word semantic processing in patients with ATL resection is supported by upregulation of semantic knowledge and control regions, principally in the undamaged hemisphere, and 2) pictorial semantic processing is less affected, presumably because it draws on a more bilateral network.

[Two Cases of Curative Resection of Locally Advanced Rectal Cancer after Preoperative Chemotherapy].

PubMed

Mitsuhashi, Noboru; Shimizu, Yoshiaki; Kuboki, Satoshi; Yoshitomi, Hideyuki; Kato, Atsushi; Ohtsuka, Masayuki; Shimizu, Hiroaki; Miyazaki, Masaru

2015-11-01

Reports of conversion in cases of locally advanced colorectal cancer have been increasing. Here, we present 2 cases in which curative resection of locally advanced rectal cancer accompanied by intestinal obstruction was achieved after establishing a stoma and administering chemotherapy. The first case was of a 46-year-old male patient diagnosed with upper rectal cancer and intestinal obstruction. Because of a high level of retroperitoneal invasion, after establishing a sigmoid colostomy, 13 courses of mFOLFOX6 plus Pmab were administered. Around 6 months after the initial surgery, low anterior resection for rectal cancer and surgery to close the stoma were performed. Fourteen days after curative resection, the patient was discharged from the hospital. The second case was of a 66-year-old male patient with a circumferential tumor extending from Rs to R, accompanied by right ureter infiltration and sub-intestinal obstruction. After establishing a sigmoid colostomy, 11 courses of mFOLFOX6 plus Pmab were administered. Five months after the initial surgery, anterior resection of the rectum and surgery to close the stoma were performed. Twenty days after curative resection, the patient was released from the hospital. No recurrences have been detected in either case.

Mechanisms of anterior-posterior stability of the knee joint under load-bearing.

PubMed

Reynolds, Ryan J; Walker, Peter S; Buza, John

2017-05-24

The anterior-posterior (AP) stability of the knee is an important aspect of functional performance. Studies have shown that the stability increases when compressive loads are applied, as indicated by reduced laxity, but the mechanism has not been fully explained. A test rig was designed which applied combinations of AP shear and compressive forces, and measured the AP displacements relative to the neutral position. Five knees were evaluated at compressive loads of 0, 250, 500, and 750N, with the knee at 15° flexion. At each load, three cycles of shear force at ±100N were applied. For the intact knee under load, the posterior tibial displacement was close to zero, due to the upward slope of the anterior medial tibial surface. The soft tissues were then resected in sequence to determine their role in AP laxity. After anterior cruciate ligament (ACL) resection, the anterior tibial displacement increased significantly even under load, highlighting its importance in stability. Meniscal resection further increased displacement but also the vertical displacement increased, implying the meniscus was providing a buffering effect. The PCL had no effect on any of the displacements under load. Plowing cartilage deformation and surface friction were negligible. This work highlighted the particular importance of the upward slope of the anterior medial tibial surface and the ACL to AP knee stability under load. The results are relevant to the design of total knees which reproduce anatomic knee stability behavior. Copyright © 2017. Published by Elsevier Ltd.

Anterior urethral valves: an uncommon cause of obstructive uropathy in children.

PubMed

Kibar, Yusuf; Coban, Hidayet; Irkilata, H Cem; Erdemir, Fikret; Seckin, Bedrettin; Dayanc, Murat

2007-10-01

Anterior urethral valves (AUV) are rare entities generally described in case reports. They are an uncommon cause of lower urinary tract obstruction in children and can be difficult to diagnose. In the present study, we present our experience in four children with AUV along with a literature review. We retrospectively identified four children with AUV presented between 1998 and 2005 at age 4-9 years. Hematuria, urinary tract infection and weak voiding stream were the most common symptoms. Voiding cystourethrography (VCUG) confirmed the diagnosis of AUV. On cystourethroscopy, cusp-like valves in the anterior urethra were seen in all children. Transurethral endoscopic resection of the valves was carried out in three children using a pediatric resectoscope. In one child with a massive anterior urethral diverticulum, open resection of the valve, diverticulectomy and urethroplasty were performed. All patients were cured, none had complications as a result of surgery, and all reported a normal urinary stream at follow-up. Children with poor stream and recurrent infections should be evaluated carefully and anterior urethral valves should be considered in differential diagnosis of obstructive lesions.

[The "window" surgical exposure strategy of the upper anterior cervical retropharyngeal approach for anterior decompression at upper cervical spine].

PubMed

Wu, Xiang-Yang; Zhang, Zhe; Wu, Jian; Lü, Jun; Gu, Xiao-Hui

2009-11-01

To investigate the "window" surgical exposure strategy of the upper anterior cervical retropharyngeal approach for the exposure and decompression and instrumentation of the upper cervical spine. From Jan. 2000 to July 2008, 5 patients with upper cervical spinal injuries were treated by surgical operation included 4 males and 1 female with and average age of 35 years old ranging from 16 to 68 years. There were 2 cases of Hangman's fractures (type II ), 2 of C2.3 intervertebral disc displacement and 1 of C2 vertebral body tuberculosis. All patients underwent the upper cervical anterior retropharyngeal approach through the "window" between the hypoglossal nerve and the superior laryngeal nerve and pharynx and carotid artery. Two patients of Hangman's fractures underwent the C2,3 intervertebral disc discectomy, bone graft fusion and internal fixation. Two patients of C2,3 intervertebral disc displacement underwent the C2,3 intervertebral disc discectomy, decompression bone graft fusion and internal fixation. One patient of C2 vertebral body tuberculosis was dissected and resected and the focus and the cavity was filled by bone autografting. C1 anterior arch to C3 anterior vertebral body were successful exposed. Lesion resection or decompression and fusion were successful in all patients. All patients were followed-up for from 5 to 26 months (means 13.5 months). There was no important vascular and nerve injury and no wound infection. Neutral symptoms was improved and all patient got successful fusion. The "window" surgical exposure surgical technique of the upper cervical anterior retropharyngeal approach is a favorable strategy. This approach strategy can be performed with full exposure for C1-C3 anterior anatomical structure, and can get minimally invasive surgery results and few and far between wound complication, that is safe if corresponding experience is achieved.

[Case-control study on transverse carpal ligament resection for the prevention of delayed carpal tunnel syndrome after distal radius fracture].

PubMed

Wang, Yan-jie; Wang, Shi-gang; Miao, Shu-juan; Su, Xia

2011-06-01

To investigate the effects of open reduction by palm side for the distal radius fracture and T shape plate internal fixation with simultaneous anterior transverse carpal ligament resection for the prevention of delayed carpal tunnel syndrome after operation. From March 2000 to March 2007, 32 patients (8 males and 24 females, ranging in age from 46 to 66 years) with distal radius fracture were treated with open reduction by palm side and T shape plate internal fixation with simultaneous anterior transverse carpal ligament resection; while 30 patients (7 males and 23 females,ranging in age from 45 to 65 years) only with open reduction by palm side and T shape plate internal fixation. The incidences of delayed carpal tunnel syndrome between the two groups were compared. Among 32 patients treated with open reduction by palm side and T shape plate internal fixation with anterior transverse carpal ligament resection, 3 patients had delayed carpal tunnel syndrome; while in 30 patients treated with open reduction by palm side and T shape plate internal fixation, 10 patients had delayed carpal tunnel syndrome. There was significant statistically difference (P < 0.05%). Simultaneous anterior transverse carpal ligament resection can effectively prevent the delayed carpal tunnel syndrome occurrence for the distal radius fracture with open reduction by palm side.

Outcomes of patients with abdominoperineal resection (APR) and low anterior resection (LAR) who had very low rectal cancer.

PubMed

Yeom, Seung-Seop; Park, In Ja; Jung, Sung Woo; Oh, Se Heon; Lee, Jong Lyul; Yoon, Yong Sik; Kim, Chan Wook; Lim, Seok-Byung; Kim, Nayoung; Yu, Chang Sik; Kim, Jin Cheon

2017-10-01

We compared the oncological outcomes of sphincter-saving resection (SSR) and abdominoperineal resection (APR) in 409 consecutive patients with very low rectal cancer (i.e., tumors within 3 cm from the anal verge); 335 (81.9%) patients underwent APR and 74 (18.1%) underwent SSR. The APR group comprised higher proportions of men (67.5% vs 55.4%, P = .049) and advanced-stage patients (P < .001). Preoperative chemoradiotherapy (PCRT) was more frequently administered in the SSR group (83.8% vs 52.8%, P < .001). Overall, the systemic and local recurrence rates were 29.1% and 6.1%, respectively. On stratification according to PCRT and pathologic stage, the mode of surgery did not affect the recurrence type. Moreover, recurrence-free survival (RFS) did not differ according to the mode of surgery in different cancer stages. RFS was associated with ypT and ypN stages in patients who received PCRT, while pN stage, lymphovascular invasion (LVI), and circumferential resection margin (CRM) involvement were risk factors for RFS in those who did not receive PCRT. Notably, SSR was not found to be a risk factor for RFS in either subgroup. Patients who were stratified according to cancer stage and PCRT also showed no differences in RFS according to the mode of surgery. Our results demonstrate that, regardless of PCRT administration, SSR is an effective treatment for very low rectal cancer, while CRM is an important prognostic factor for patients who did not receive PCRT.

Anterior clinoidectomy using an extradural and intradural 2-step hybrid technique.

PubMed

Tayebi Meybodi, Ali; Lawton, Michael T; Yousef, Sonia; Guo, Xiaoming; González Sánchez, Jose Juan; Tabani, Halima; García, Sergio; Burkhardt, Jan-Karl; Benet, Arnau

2018-02-23

Anterior clinoidectomy is a difficult yet essential technique in skull base surgery. Two main techniques (extradural and intradural) with multiple modifications have been proposed to increase efficiency and avoid complications. In this study, the authors sought to develop a hybrid technique based on localization of the optic strut (OS) to combine the advantages and avoid the disadvantages of both techniques. Ten cadaveric specimens were prepared for surgical simulation. After a standard pterional craniotomy, the anterior clinoid process (ACP) was resected in 2 steps. The segment anterior to the OS was resected extradurally, while the segment posterior to the OS was resected intradurally. The proposed technique was performed in 6 clinical cases to evaluate its safety and efficiency. Anterior clinoidectomy was successfully performed in all cadaveric specimens and all 6 patients by using the proposed technique. The extradural phase enabled early decompression of the optic nerve while avoiding the adjacent internal carotid artery. The OS was drilled intradurally under direct visualization of the adjacent neurovascular structures. The described landmarks were easily identifiable and applicable in the surgically treated patients. No operative complication was encountered. A proposed 2-step hybrid technique combines the advantages of the extradural and intradural techniques while avoiding their disadvantages. This technique allows reduced intradural drilling and subarachnoid bone dust deposition. Moreover, the most critical part of the clinoidectomy-that is, drilling of the OS and removal of the body of the ACP-is left for the intradural phase, when critical neurovascular structures can be directly viewed.

The distal fascicle of the anterior inferior tibio-fibular ligament as a cause of anterolateral ankle impingement: results of arthroscopic resection.

PubMed

Akseki, D; Pinar, H; Bozkurt, M; Yaldiz, K; Araç, S

1999-10-01

We arthroscopically resected the impinged distal fascicle of the anterior inferior tibiofibular ligament (AIT-FL) in 21 patients (mean age 31 (11-68) years, 14 women) with chronic ankle pain after an ankle sprain. Clinical tests revealed moderate laxity in 2 and severe laxity in another 2, the remaining 17 ankles showing only mild laxity. During arthroscopy, an impinging distal fascicle of the AITFL was found in all cases. Following anterolateral synovectomy, the fascicle was excised. At the follow-up after mean 3 (2-4) years, good-to-excellent results were obtained in 17 patients. 19 patients were satisfied with the procedure and 17 patients returned to their previous level of activity. 2 patients who had mild laxity were graded as poor because of neuromas of the terminal branches of the superficial peroneal nerve. These patients became asymptomatic after an injection of steroids.

Ultra-low dose naltrexone enhances cannabinoid-induced antinociception.

PubMed

Paquette, Jay; Olmstead, Mary C; Olmstead, Mary

2005-12-01

Both opioids and cannabinoids have inhibitory effects at micromolar doses, which are mediated by activated receptors coupling to Gi/o-proteins. Surprisingly, the analgesic effects of opioids are enhanced by ultra-low doses (nanomolar to picomolar) of the opioid antagonist, naltrexone. As opioid and cannabinoid systems interact, this study investigated whether ultra-low dose naltrexone also influences cannabinoid-induced antinociception. Separate groups of Long-Evans rats were tested for antinociception following an injection of vehicle, a sub-maximal dose of the cannabinoid agonist WIN 55 212-2, naltrexone (an ultra-low or a high dose) or a combination of WIN 55 212-2 and naltrexone doses. Tail-flick latencies were recorded for 3 h, at 10-min intervals for the first hour, and at 15-min intervals thereafter. Ultra-low dose naltrexone elevated WIN 55 212-2-induced tail flick thresholds without extending its duration of action. This enhancement was replicated in animals receiving intraperitoneal or intravenous injections. A high dose of naltrexone had no effect on WIN 55 212-2-induced tail flick latencies, but a high dose of the cannabinoid 1 receptor antagonist SR 141716 blocked the elevated tail-flick thresholds produced by WIN 55 212-2+ultra-low dose naltrexone. These data suggest a mechanism of cannabinoid-opioid interaction whereby activated opioid receptors that couple to Gs-proteins may attenuate cannabinoid-induced antinociception and/or motor functioning.

Aneurysmal bone cyst of C2 treated with novel anterior reconstruction and stabilization.

PubMed

Rajasekaran, S; Aiyer, Siddharth N; Shetty, Ajoy Prasad; Kanna, Rishi; Maheswaran, Anupama

2016-03-23

Aneurysmal bone cysts (ABC) form 1 % of primary bone tumors. Reported incidence rates are no more than 1.4 to 1,00,000. ABC of spine frequently involves posterior elements and commonly affects the lumbar spine (45 %). We present a case of C2 ABC for the challenges it poses due to the rarity of the lesion, tedious to access location, dilemmas relating to the suitable approach for tumor resection and technically demanding stabilization and reconstruction strategy post resection. Clinical data analysis was performed to discuss a method of novel anterior column reconstruction following resection of a C2 aneurysmal bone cyst in a 8 year old child with anterior and posterior elements being involved. An 8-year-old girl with an aneurysmal bone cyst of the C2 vertebra underwent staged surgery following pre-operative embolisation. First a posterior approach tumor excision with posterior instrumented fusion was performed. Following which, using a modified anterior retropharyngeal approach anterior tumor excision and fibular graft reconstruction between the C1 lateral mass and C2 body was performed. Complete tumor clearance and stable reconstruction was successfully achieved in our patient. Patient showed excellent clinical outcome with radiological fusion. Preoperative embolisation in the treatment of ABC has supplemental advantage by reducing blood loss. Modified anterior retropharyngeal approach allows satisfactory clearance for C1-2 lesion and fibular strut graft between the C1 lateral mass and C2 body can provide a stable graft placement with good chance of fusion. Instability and spinal deformity, whether preexisting or post-excision, should be corrected with reconstruction and stabilization to offer best chance of cure in such cases.

Olfactory preservation during anterior interhemispheric approach for anterior skull base lesions: technical note.

PubMed

Matano, Fumihiro; Murai, Yasuo; Mizunari, Takayuki; Tateyama, Kojiro; Kobayashi, Shiro; Adachi, Koji; Kamiyama, Hiroyasu; Morita, Akio; Teramoto, Akira

2016-01-01

Anosmia is not a rare complication of surgeries that employ the anterior interhemispheric approach. Here, we present a fibrin-gelatin fixation method that provides reinforcement and moisture to help preserve the olfactory nerve when using the anterior interhemispheric approach and describe the results and outcomes of this technique. We analyze the outcomes with this technique in 45 patients who undergo surgery for aneurysms, brain tumors, or other pathologies via the anterior interhemispheric approach. Anosmia occurred in 4 patients (8.8%); it was transient in 2 (4.4%) and permanent in the remaining 2 (4.4%). Brain tumors clearly attached to the olfactory nerve were resected in the patients with permanent anosmia. We found a significant difference in the presence of anosmia between patients with or without lesions that were attaching the olfactory nerve (p = 0.011). Our results suggested that fibrin-gelatin fixation method can reduce the reported risk of anosmia. However, the possibility of olfactory nerve damage is relatively high when operating on brain tumors attaching olfactory nerve.

Ultralow Dose MSCT Imaging in Dental Implantology

PubMed Central

Widmann, Gerlig; Al-Ekrish, Asma'a A.

2018-01-01

Introduction: The Council Directive 2013/59 Euratom has a clear commitment for keeping medical radiation exposure as low as reasonably achievable and demands a regular review and use of diagnostic reference levels. Methods: In dental implantology, the range of effective doses for cone beam computed tomography (CBCT) shows a broad overlap with multislice computed tomography (MSCT). More recently, ultralow dose imaging with new generations of MSCT scanners may impart radiation doses equal to or lower than CBCT. Dose reductions in MSCT have been further facilitated by the introduction of iterative image reconstruction technology (IRT), which provides substantial noise reduction over the current standard of filtered backward projection (FBP). Aim: The aim of this article is to review the available literature on ultralow dose CT imaging and IRTs in dental implantology imaging and to summarize their influence on spatial and contrast resolution, image noise, tissue density measurements, and validity of linear measurements of the jaws. Conclusion: Application of ultralow dose MSCT with IRT technology in dental implantology offers the potential for very large dose reductions compared with standard dose imaging. Yet, evaluation of various diagnostic tasks related to dental implantology is still needed to confirm the results obtained with various IRTs and ultra-low doses so far. PMID:29492174

A meta-analysis of the use of a transanal drainage tube to prevent anastomotic leakage after anterior resection by double-stapling technique for rectal cancer.

PubMed

Shigeta, Kohei; Okabayashi, Koji; Baba, Hideo; Hasegawa, Hirotoshi; Tsuruta, Masashi; Yamafuji, Kazuo; Kubochi, Kiyoshi; Kitagawa, Yuko

2016-02-01

The safety and efficacy of transanal drainage tube (TDT) placement to decrease the risk of postoperative anastomotic leakage after rectal cancer surgery has not been validated. The objective of this meta-analysis was to evaluate the usefulness of a TDT for the prevention of anastomotic leakage after an anterior resection for rectal cancer. The PubMed and Cochrane Library databases were searched for studies comparing TDT and non-TDT. The endpoint utilized in this study was defined as the rates of anastomotic leakage and re-operation. The relative effects of these variables were synthesized using Review Manager 5.1 software. Four trials including 909 participants (401 TDT cases and 508 non-TDT cases) met our inclusion criteria. The weighted mean anastomotic leakage rate was 4% [95% confidence interval (CI) 1-6%], and a significantly lower risk of anastomotic leakage was identified in the TDT group compared with the non-TDT group [odds ratio (OR) 0.30; 95% CI 0.16-0.55; p = 0.0001]. Furthermore, there were significant differences between the TDT and non-TDT groups in terms of the re-operation rate (OR 0.18; 95% CI 0.07-0.44; p = 0.0002). No significant covariates related to anastomotic leakage or re-operation were identified in meta-regression analysis. Both the anastomotic leakage and re-operation rates for all studies lay inside the 95% confidence interval boundaries. No visible publication bias was found by visual assessment of the funnel plot (Egger's test; anastomotic leakage: p = 0.056, re-operation: p = 0.681). Placement of a TDT is an effective and safe procedure that can decrease the rate of anastomotic leakage and re-operation after an anterior resection.

Transcallosal, Transchoroidal Resection of a Recurrent Craniopharyngioma.

PubMed

Jean, Walter C

2018-04-01

Objective  To demonstrate the transchoroidal approach for the resection of a recurrent craniopharyngioma. Design  Video case report. Setting  Microsurgical resection. Participant  The patient was a 27-year-old woman with a history of a craniopharyngioma, resected twice during the year prior to presentation to our unit. Both operations were done via the left anterolateral corridor, and afterward, she was blind in the left eye and was treated with Desmopressin (DDAVP) for diabetes insipidus (DI). Serial magnetic resonance imaging (MRI) showed progression of the tumor residual, and she was referred for further surgical intervention. Main Outcome Measures  Pre- and postoperative MRIs measured the degree of resection. Results  For this, her third surgery, a transcallosal, transchoroidal approach, was chosen to offer the widest possible exposure. Given her history, an aggressive total resection was the best strategy. The patient was placed supine with the head neutral. A right frontal craniotomy allowed access to the interhemispheric fissure. By opening the corpus callosum, the left lateral ventricle was entered. The transchoroidal approach started with dissection of the tenia fornicis to open the choroidal fissure. After this, sufficient exposure to the posterior parts of the tumor was gained. Resection proceeded to the bottom of the tumor, exposing the basilar apex and interpeduncular cistern, and continued back anteriorly. In the end, a microscopic total resection was achieved. With a long hospital stay to treat her brittle DI, the patient slowly returned to neurological baseline. Conclusion  The transchoroidal approach is an effective way to remove large tumors in the third ventricle. The link to the video can be found at: https://youtu.be/2-Aqjaay8dg .

Ultra-low dose (+)-naloxone restores the thermal threshold of morphine tolerant rats.

PubMed

Chou, Kuang-Yi; Tsai, Ru-Yin; Tsai, Wei-Yuan; Wu, Ching-Tang; Yeh, Chun-Chang; Cherng, Chen-Hwan; Wong, Chih-Shung

2013-12-01

As known, long-term morphine infusion leads to tolerance. We previously demonstrated that both co-infusion and post-administration of ultra-low dose (±)-naloxone restores the antinociceptive effect of morphine in morphine-tolerant rats. However, whether the mechanism of the action of ultra-low dose (±)-naloxone is through opioid receptors or not. Therefore, in the present study, we further investigated the effect of ultra-low dose (+)-naloxone, it does not bind to opioid receptors, on the antinociceptive effect of morphine. Male Wistar rats were implanted with one or two intrathecal (i.t.) catheters; one catheter was connected to a mini-osmotic pump, used for morphine (15 μg/h), ultra-low dose (+)-naloxone (15 pg/h), morphine plus ultra-low dose (+)-naloxone (15 pg/h) or saline (1 μl/h) infusion for 5 days. On day 5, either ultra-low dose (+)-naloxone (15 pg) or saline (5 μl) was injected via the other catheter immediately after discontinued morphine or saline infusion. Three hours later, morphine (15 μg in 5 μl saline) or saline were given intrathecally. All rats received nociceptive tail-flick test every 30 minutes for 120 minutes after morphine challenge at different temperature (45-52°C, respective). Our results showed that, both co-infusion and post-treatment of ultra-low dose (+)-naloxone with morphine preserves the antinociceptive effect of morphine. Moreover, in the post administration rats, ultra-low dose (+)-naloxone further enhances the antinociceptive effect of morphine. This study provides an evidence for ultra-low dose (+)-naloxone as a therapeutic adjuvant for patients who need long-term opioid administration for pain management. Copyright © 2013. Published by Elsevier B.V.

[Electrocoagulation on a fragment of anterior abdominal rectal muscle for the control of presacral bleeding during rectal resection].

PubMed

Casal Núñez, José Enrique; Martínez, María Teresa García; Poblador, Alejandro Ruano

2012-03-01

Presacral venous haemorrhage during rectal movement is low, but is often massive, and even fatal. Our objective is the "in vitro" determination of the results of electrocoagulation applied to a fragment of muscle on the sacral bone surface during rectal resection due to a malignant neoplasm of the rectum. Single-pole coagulation was applied "in vitro" with the selector at maximum power on a 2×2 cms muscle fragment, applied to the anterior side of the IV sacral vertebra until reaching boiling point. The method was used on 6 patients with bleeding of the presacral venous plexus. In the "in vitro" study, boiling point was reached in 90 seconds from applying the single-pole current on the muscle fragment. Electrocoagulation was applied to a 2×2 cm rectal muscle fragment in 6 patients with presacral venous haemorrhage, using pressure on the surface of the presacral bone, with the stopping of the bleeding being achieved in all cases. The use of indirect electrocoagulation on a fragment of the rectus abdominis muscle is a straightforward and highly effective technique for controlling presacral venous haemorrhage. Copyright © 2011 AEC. Published by Elsevier Espana. All rights reserved.

Prospective assessment of the quality of life in patients treated surgically for rectal cancer with lower anterior resection and abdominoperineal resection.

PubMed

Monastyrska, E; Hagner, W; Jankowski, M; Głowacka, I; Zegarska, B; Zegarski, W

2016-11-01

Rectal cancer is the most common malignant neoplasm of the gastrointestinal tract. The aim of the study was to assess the quality of life in patients undergoing surgical treatment for the rectal cancer, either lower anterior or abdominoperineal resection. 100 patients suffering from rectal cancer were selected for a prospective study (50-APR, 50-LAR). The quality of life was assessed two times: at the admission to the Department and 6 months following surgery. For assessment of the quality of life, two standard questionnaires were used, EORT QLQ-C30 and EORTC QLQ-C29. The studied groups were not different with respect to demographic factors. The patients who underwent LAR spent less time in hospital (p = 0.00001). The patients undergoing APR scored less with respect to physical ability (p = 0.0434), cognitive (p = 0.0363) and emotional state (p = 0.0463) and on symptom scale (nausea and vomiting - p: 0.0199, diarrhea - p: 0.0000, constipation (p = 0.0018)); however, the patients who were treated with LAR scored less on pain scale (p = 0.0189). The QLQ-C29 questionnaire revealed impaired functioning of patients 6 months following APR in terms of life chances (p = 0.0000) and problems with body weight (p = 0.0212). In both groups, the quality of life improved 6 months after surgery. LAR is a chance for better quality of life for many patients. Six months after surgery, the quality of life of patients improves regardless of the operating method (APR, LAR). Copyright © 2016 Elsevier Ltd, BASO ~ the Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

[Anterior urethral valves and anterior urethral diverticulum, are they same entity?

PubMed

Calleja Aguayo, E; Hernández Calvarro, A E; Bregante Ucedo, J; Marhuenda Irastorza, C

2015-04-15

We present our experience in the diagnosis and management of anterior urethral valves (AUV) and anterior urethral diverticula (AUD) as well as review of the bibliography. We retrospectively evaluated all the cases of the AUV and AUD treated in our hospital during the last 10 years. The clinical exploration, renal function study and renal and bladder ultrasound were evaluated in all the children. The diagnosis was completed with voiding cystography (VCUG) and cystoscopy as well as nuclear study in the relevant patients. Four patients have been treated in our center. AUV was suspected in those children with narrowing of the anterior urethra and thickened bladder with trabeculations at the VCUG. These findings were noticed in 50% of the patients, which also had a neonatal presentation. The diagnosis was confirmed by cystoscopy that allowed the endoscopic resection at the same procedure. The boys with AUD were managed by excision of the diverticulum with urethroplasty. On the follow up, one patient who had AUV, presented renal involvement in the nuclear scans with normal renal function. In our experience, the AUV and AUD behave as two different entities in terms of clinical presentation and treatment. The AUV have been effectively treated with endoscopic surgery and the AUD have pointed out open surgery, as described in the literature.

Arthroscopic Resection of a Large Bony Exostosis Arising from the Anterior Inferior Iliac Spine Causing Extra-articular Hip Impingement: A Case Series

PubMed Central

Carton, Patrick; Filan, David

2016-01-01

Introduction: Abnormal morphology of the anterior inferior iliac spine (AIIS) is a rarely recognized but important source of extra-articular hip impingement. Chronic progressive symptoms of stiffness and limitation of hip motion with persistent groin pain may place significant restriction on activity. Concomitant femoroacetabular impingement is often present but recognition and effective treatment of the uncommon extra-articular component is important for successful outcome. Case Report: Three cases of symptomatic extra-articular hip impingement secondary to AIIS deformity and in conjunction with mild underlying femoroacetabular impingement (FAI) are presented. They include two athletic Caucasian males aged 27 and 35-years old with a history of prior rectus tendon injury and secondary bony exostosis formation and a 53-year-old Caucasian male with a nontraumatic, developmental AIIS deformity. In all cases, an excellent clinical outcome with a full return to pain free activity was achieved postoperation. Their clinical presentation, diagnosis and post-operative outcome at 1.5-2 years (mean 1.7 years) following arthroscopic AIIS resection are discussed. Conclusion: Arthroscopic management of AIIS extra-articular hip impingement has been rarely reported and the longer-term outcome is unknown. We report the successful clinical outcome in a case series of three patients up to 2 years following arthroscopic AIIS resection. This case series demonstrates the sustainable benefits of arthroscopic correction of AIIS bony exostosis as a cause of extra-articular FAI. PMID:29537397

Aggressive resection of frequent peritoneal recurrences in colorectal cancer contributes to long-term survival.

PubMed

Komori, Koji; Kinoshita, Takashi; Taihei, Oshiro; Ito, Seiji; Abe, Tetsuya; Senda, Yoshiki; Misawa, Kazunari; Ito, Yuich; Uemura, Norihisa; Natsume, Seiji; Kawakami, Jiro; Ouchi, Akira; Tsutsuyama, Masayuki; Hosoi, Takahiro; Shigeyoshi, Itaru; Akazawa, Tomoyuki; Hayashi, Daisuke; Tanaka, Hideharu; Shimizu, Yasuhiro

2016-12-01

We report a long-term survivor of colorectal cancer who underwent aggressive, frequent resection for peritoneal recurrences. A 58-year-old woman was diagnosed with descending colon cancer. Resection of the descending colon along with lymph node dissection was performed in September 2006. The pathological findings revealed Stage IIA colorectal cancer. The following peritoneal recurrences were removed: two in July 2007, two in the omental fat and two in the pouch of Douglas in June 2008 resected by low anterior resection of the rectum, one in the uterus and right ovarian recurrence resected via bilateral adnexectomy and Hartmann's procedure in May 2011, and one in the ascending colon by partial resection of the colon wall in December 2011. Postoperative adjuvant chemotherapy (uracil and tegafur/leucovorin, fluorouracil/levofolinate/oxaliplatin/bevacizumab, 5-fluorouracil/leucovorin/bevacizumab, irinotecan/bevacizumab, and irinotecan/panitumumab) was administered. The patient did not desire postoperative adjuvant chemotherapy after the fourth operation. The long-term survival was 6 years and 7 months.

Application of CUSA Excel ultrasonic aspiration system in resection of skull base meningiomas.

PubMed

Tang, Hailiang; Zhang, Haishi; Xie, Qing; Gong, Ye; Zheng, Mingzhe; Wang, Daijun; Zhu, Hongda; Chen, Xiancheng; Zhou, Liangfu

2014-12-01

Here, we introduced our short experience on the application of a new CUSA Excel ultrasonic aspiration system, which was provided by Integra Lifesciences corporation, in skull base meningiomas resection. Ten patients with anterior, middle skull base and sphenoid ridge meningioma were operated using the CUSA Excel ultrasonic aspiration system at the Neurosurgery Department of Shanghai Huashan Hospital from August 2014 to October 2014. There were six male and four female patients, aged from 38 to 61 years old (the mean age was 48.5 years old). Five cases with tumor located at anterior skull base, three cases with tumor on middle skull base, and two cases with tumor on sphenoid ridge. All the patents received total resection of meningiomas with the help of this new tool, and the critical brain vessels and nerves were preserved during operations. All the patients recovered well after operation. This new CUSA Excel ultrasonic aspiration system has the advantage of preserving vital brain arteries and cranial nerves during skull base meningioma resection, which is very important for skull base tumor operations. This key step would ensure a well prognosis for patients. We hope the neurosurgeons would benefit from this kind of technique.

Effect of Laparoscopic-Assisted Resection vs Open Resection of Stage II or III Rectal Cancer on Pathologic Outcomes

PubMed Central

Fleshman, James; Branda, Megan; Sargent, Daniel J.; Boller, Anne Marie; George, Virgilio; Abbas, Maher; Peters, Walter R.; Maun, Dipen; Chang, George; Herline, Alan; Fichera, Alessandro; Mutch, Matthew; Wexner, Steven; Whiteford, Mark; Marks, John; Birnbaum, Elisa; Margolin, David; Larson, David; Marcello, Peter; Posner, Mitchell; Read, Thomas; Monson, John; Wren, Sherry M.; Pisters, Peter W. T.; Nelson, Heidi

2016-01-01

IMPORTANCE Evidence about the efficacy of laparoscopic resection of rectal cancer is incomplete, particularly for patients with more advanced-stage disease. OBJECTIVE To determine whether laparoscopic resection is noninferior to open resection, as determined by gross pathologic and histologic evaluation of the resected proctectomy specimen. DESIGN, SETTING, AND PARTICIPANTS A multicenter, balanced, noninferiority, randomized trial enrolled patients between October 2008 and September 2013. The trial was conducted by credentialed surgeons from 35 institutions in the United States and Canada. A total of 486 patients with clinical stage II or III rectal cancer within 12 cm of the anal verge were randomized after completion of neoadjuvant therapy to laparoscopic or open resection. INTERVENTIONS Standard laparoscopic and open approaches were performed by the credentialed surgeons. MAIN OUTCOMES AND MEASURES The primary outcome assessing efficacy was a composite of circumferential radial margin greater than 1 mm, distal margin without tumor, and completeness of total mesorectal excision. A 6%noninferiority margin was chosen according to clinical relevance estimation. RESULTS Two hundred forty patients with laparoscopic resection and 222 with open resection were evaluable for analysis of the 486 enrolled. Successful resection occurred in 81.7%of laparoscopic resection cases (95%CI, 76.8%–86.6%) and 86.9%of open resection cases (95%CI, 82.5%–91.4%) and did not support noninferiority (difference, −5.3%; 1-sided 95%CI, −10.8%to ∞; P for noninferiority = .41). Patients underwent low anterior resection (76.7%) or abdominoperineal resection (23.3%). Conversion to open resection occurred in 11.3%of patients. Operative time was significantly longer for laparoscopic resection (mean, 266.2 vs 220.6 minutes; mean difference, 45.5 minutes; 95%CI, 27.7–63.4; P < .001). Length of stay (7.3 vs 7.0 days; mean difference, 0.3 days; 95%CI, −0.6 to 1.1), readmission within 30

Microsurgical Resection of Suprasellar Craniopharyngioma-Technical Purview.

PubMed

Nanda, Anil; Narayan, Vinayak; Mohammed, Nasser; Savardekar, Amey R; Patra, Devi Prasad

2018-04-01

Objectives  Complete surgical resection is an important prognostic factor for recurrence and is the best management for craniopharyngioma. This operative video demonstrates the technical nuances in achieving complete resection of a suprasellar craniopharyngioma. Design and Setting  The surgery was performed in a middle-aged lady who presented with the history of progressive bitemporal hemianopia and excessive sleepiness over 8 months. On imaging, suprasellar craniopharyngioma was identified. The tumor was approached through opticocarotid cistern and lamina terminalis. Exposure of bilateral optic nerves, right internal carotid artery, anterior cerebral artery, and its perforator branches was then afforded and the tumor was gross totally resected. Results  The author demonstrates step-by-step technique of microsurgical resection of suprasellar craniopharyngioma. The narrow corridor to deeper structures, intricacies of multiple perforator vessels, and the technique of arachnoid and capsule dissection are the main challenging factors for the gross total resection of craniopharyngioma. The tumor portion which lies under the ipsilateral optic nerve is a blind spot region with a high chance of leaving residual tumor. Mobilization of optic nerve may endanger visual function too. The use of handheld mirror ['mirror-technique'] helps in better visualization of this blind spot and achieve complete excision. Conclusions  The technical pearls of craniopharyngioma surgery include the optimum utilization of translamina terminalis route, wide opening of the cisterns, meticulous separation of deep perforator vessels, capsular mobilization/traction avoidance, and the use of "mirror-technique" for blind-spot visualization. These surgical strategies help to achieve complete resection without causing neurological deficit. The link to the video can be found at: https://youtu.be/9wHJ4AUpG50 .

A 40-year-old woman with cauda equina syndrome caused by rectothecal fistula arising from an anterior sacral meningocele.

PubMed

Bergeron, Eric; Roux, Alain; Demers, Jacques; Vanier, Laurent E; Moore, Lynne

2010-11-01

We present a rare case of a rectothecal fistula arising from an anterior sacral meningocele in a patient with Currarino syndrome. The patient was a 40-year-old woman presenting with cauda equina syndrome and ascending meningitis. The meningocele was removed using an anterior abdominal approach. A sigmoid resection was performed with rectal on-table antegrade lavage followed by closure of the rectal fistula, closure of the rectal stump, and proximal colostomy. Closure of the sacral deficit was carried out by suturing a strip of well-vascularized omentum and fibrin glue. We discuss the characteristics, management, and evolution of this unusual case. Prompt surgical management using an anterior approach, resection of the sac, closure of the sacral deficit, and fecal diversion resulted in a satisfactory outcome.

Assessment of frontal lobe sagging after endoscopic endonasal transcribriform resection of anterior skull base tumors: is rigid structural reconstruction of the cranial base defect necessary?

PubMed

Eloy, Jean Anderson; Shukla, Pratik A; Choudhry, Osamah J; Singh, Rahul; Liu, James K

2012-12-01

The endoscopic endonasal transcribriform approach (EETA) is a viable alternative option for resection of selected anterior skull base (ASB) tumors. However, this technique results in the creation of large cribriform defects. Some have reported the use of a rigid substitute for ASB reconstruction to prevent postoperative frontal lobe sagging. We evaluate the degree of frontal lobe sagging using our triple-layer technique [fascia lata, acellular dermal allograft, and pedicled nasoseptal flap (PNSF)] without the use of rigid structural reconstruction for large cribriform defects. Retrospective analysis. Nine patients underwent an EETA for resection of large ASB tumors from August 2010 to November 2011. The degree of frontal lobe displacement after EETA, defined as the ASB position, was calculated based on the most inferior position of the frontal lobe relative to the nasion-sellar line defined on preoperative and postoperative imaging. A positive value signified upward displacement, and a negative value represented inferior displacement of the frontal lobe. The average cribriform defect size was 9.3 cm(2) (range, 5.0-13.8 cm(2) ). The average distance of postoperative frontal lobe displacement was 0.2 mm (range, -3.9 to 2.9 mm) without any cases of significant brain sagging. The mean follow-up period was 10.1 months (range, 4-19 months). There were no postoperative CSF leaks. Rigid structural repair may not be necessary for ASB defect repair after endoscopic endonasal resection of the cribriform plate. Our technique for multilayer cranial base reconstruction appears to be satisfactory in preventing delayed frontal lobe sagging. Copyright © 2012 The American Laryngological, Rhinological, and Otological Society, Inc.

Robotic Posterior Mitral Leaflet Repair: Neochordal versus Resectional Techniques

PubMed Central

Mihaljevic, Tomislav; Pattakos, Gregory; Gillinov, A. Marc; Bajwa, Gurjyot; Planinc, Mislav; Williams, Sarah J.; Blackstone, Eugene H.

2013-01-01

Background Resectional techniques are the established method of posterior mitral valve leaflet repair for degenerative disease; however, use of neochordae in a robotically assisted approach is gaining acceptance because of its versatility for difficult multi-segment disease. The purposes of this study were to compare the versatility, safety, and effectiveness of neochordal vs. resectional techniques for robotic posterior mitral leaflet repair. Methods From 12/2007 to 7/2010, 334 patients underwent robotic posterior mitral leaflet repair for degenerative disease by a resectional (n=248) or neochordal (n=86) technique. Outcomes were compared unadjusted and after propensity score matching. Results Neochordae were more likely to be used than resection in patients with two (28% vs. 13%, P=.002) or three (3.7% vs. 0.87%, P=.08) diseased posterior leaflet segments. Three resection patients (0.98%) but no neochordal patient required reoperation for hemodynamically significant systolic anterior motion (SAM). Residual mitral regurgitation (MR) at hospital discharge was similar for matched neochordal vs. resection patients (P=.14) (MR 0+, 82% vs. 89%; MR 1+, 14% vs. 8.2%; MR 2+, 2.3% vs. 2.6%; one neochordal patient had 4+ MR and was reoperated). Among matched patients, postoperative mortality and morbidity were similarly low. Conclusion Compared with a resectional technique, robotic posterior mitral leaflet repair with neochordae is associated with shorter operative times and no occurrence of SAM. The versatility, effectiveness, and safety of this repair make it a good choice for patients with advanced multi-segment disease. PMID:23103008

Internal Carotid Artery Sacrifice for Radical Resection of Skull Base Tumors

PubMed Central

Lawton, Michael T.; Spetzler, Robert F.

1996-01-01

When dealing with skull base tumors that encase the internal carotid artery (ICA), the surgeon must decide between ICA preservation and incomplete tumor resection, or radical resection with ICA sacrifice. In our experience with more than 300 anterior skull base tumors, the ICA was sacrificed in only 10 patients. These tumors were malignant, except for one meningioma that occluded the ICA and produced translent ischemic symptoms. All patients had the ICA resected with the tumor, and all patients underwent revascularization (cervical ICA-MCA saphenous bypass, n = 4; cervical-to-supraclinoid bypass, n = 1; petrous-to-supraclinoid bypass, n = 3; bonnet bypass, n = 2). This small patient series reflects our practice of preserving the ICA whenever possible. We recommend preserving the ICA with benign tumors because they do not invade the artery, or do so only to a limited extent. In addition, similar rates of tumor recurrence are seen after aggressive resection with or without ICA sacrifice. In contrast, we recommend radical tumor resection and sacrifice of the ICA with malignant tumors because they directly threaten the integrity of the ICA and the patient's survival. The ICA should not be considered a limitation to radical tumor resection because the ICA can be reconstructed safely with an appropriate bypass procedure. PMID:17170986

Suprachiasmatic translamina terminalis corridor used in endoscopic endonasal approach for resecting third ventricular craniopharyngioma.

PubMed

Gu, Ye; Zhang, Xiaobiao; Hu, Fan; Yu, Yong; Xie, Tao; Sun, Chongjing; Li, Wensheng

2015-05-01

The translamina terminalis corridor was used in the transcranial anterior route to treat third ventricular craniopharyngioma (TVC), which presents a challenge to neurosurgeons. The endoscopic endonasal approach (EEA) has recently been used to treat craniopharyngiomas. However, there are few reports of the EEA being used to treat TVC. The authors' novel surgical approach of treating selected TVC by the endoscopic endonasal route via the suprachiasmatic translamina terminalis (STLT) corridor is described. In this single-center study, the EEA via the STLT corridor was used to resect TVC with great upper and anterior extension causing bulged lamina terminalis, and TVC with a residual upper compartment, after routine infrachiasmatic transmetastalk corridor resection. The STLT corridor was used in 3 patients. Gross-total resection was achieved in all cases. One patient achieved visual improvement, and the other 2 patients showed partial visual improvement. Leakage of CSF occurred in 1 patient. Postoperative hormone replacement therapy was required in all patients. The STLT corridor is a complementary minimally invasive corridor used in the EEA for treating selected TVC. The STLT alone or combined with infrachiasmatic transmetastalk corridors should be selected depending on the size of suprachiasmatic and infrachiasmatic space.

Open Approaches to the Anterior Skull Base in Children: Review of the Literature.

PubMed

Wasserzug, Oshri; DeRowe, Ari; Ringel, Barak; Fishman, Gadi; Fliss, Dan M

2018-02-01

Introduction  Skull base lesions in children and adolescents are rare, and comprise only 5.6% of all skull base surgery. Anterior skull base lesions dominate, averaging slightly more than 50% of the cases. Until recently, surgery of the anterior skull base was dominated by open procedures and endoscopic skull base surgery was reserved for benign pathologies. Endoscopic skull base surgery is gradually gaining popularity. In spite of that, open skull base surgery is still considered the "gold standard" for the treatment of anterior skull base lesions, and it is the preferred approach in selected cases. Objective  This article reviews current concepts and open approaches to the anterior skull base in children in the era of endoscopic surgery. Materials and Methods  Comprehensive literature review. Results  Extensive intracranial-intradural invasion, extensive orbital invasion, encasement of the optic nerve or the internal carotid artery, lateral supraorbital dural involvement and involvement of the anterior table of the frontal sinus or lateral portion of the frontal sinus precludes endoscopic surgery, and mandates open skull base surgery. The open approaches which are used most frequently for surgical resection of anterior skull base tumors are the transfacial/transmaxillary, subcranial, and subfrontal approaches. Reconstruction of anterior skull base defects is discussed in a separate article in this supplement. Discussion  Although endoscopic skull base surgery in children is gaining popularity in developed countries, in many cases open surgery is still required. In addition, in developing countries, which accounts for more than 80% of the world's population, limited access to expensive equipment precludes the use of endoscopic surgery. Several open surgical approaches are still employed to resect anterior skull base lesions in the pediatric population. With this large armamentarium of surgical approaches, tailoring the most suitable approach to a

Application of CUSA Excel ultrasonic aspiration system in resection of skull base meningiomas

PubMed Central

Tang, Hailiang; Zhang, Haishi; Xie, Qing; Zheng, Mingzhe; Wang, Daijun; Zhu, Hongda; Chen, Xiancheng; Zhou, Liangfu

2014-01-01

Background Here, we introduced our short experience on the application of a new CUSA Excel ultrasonic aspiration system, which was provided by Integra Lifesciences corporation, in skull base meningiomas resection. Methods Ten patients with anterior, middle skull base and sphenoid ridge meningioma were operated using the CUSA Excel ultrasonic aspiration system at the Neurosurgery Department of Shanghai Huashan Hospital from August 2014 to October 2014. There were six male and four female patients, aged from 38 to 61 years old (the mean age was 48.5 years old). Five cases with tumor located at anterior skull base, three cases with tumor on middle skull base, and two cases with tumor on sphenoid ridge. Results All the patents received total resection of meningiomas with the help of this new tool, and the critical brain vessels and nerves were preserved during operations. All the patients recovered well after operation. Conclusions This new CUSA Excel ultrasonic aspiration system has the advantage of preserving vital brain arteries and cranial nerves during skull base meningioma resection, which is very important for skull base tumor operations. This key step would ensure a well prognosis for patients. We hope the neurosurgeons would benefit from this kind of technique. PMID:25561762

Harvey Cushing's Meningiomas text and the historical origin of resectability criteria for the anterior one third of the superior sagittal sinus.

PubMed

Shrivastava, Raj K; Segal, Salomao; Camins, Martin B; Sen, Chandranath; Post, Kalmon D

2003-10-01

The search for the origin of the commonly held principle in current neurosurgery regarding the resectability of the anterior one third of the superior sagittal sinus unravels the many fascinating developments that occurred in neurosurgery during the early 20th century. All these occurrences can be traced back to, and are uniquely contextualized in, Harvey Cushing's seminal text, Meningiomas, Their Classification, Regional Behaviour, Life History, and Surgical End Results. Written with Louise Eisenhardt and published in 1938, Meningiomas is a monograph of incredible description and detail. The meticulous categorization of meningiomas, their presentation, clinical outcome, and surgical therapies are even further supplemented by Cushing's personal commentary, questions, and recollections. Cushing's genius was evident in his ability not only to make insightful clinical observations, but also to synthesize these ideas within the neurosurgical context of his era. As he says in Meningiomas, "Thus the pathological curiosity of one day becomes in its proper time a commonplace... most of which are one and the same disorder--had, for their interpretation, to await the advent of the Neurosurgeon."

Gastritis cystica profunda recurrence after surgical resection: 2-year follow-up

PubMed Central

2014-01-01

Background Gastritis cystica profunda (GCP) is an uncommon disease characterized by multiple cystic gastric glands within the submucosa of the stomach. Case description Here, we present a case of a 63-year-old man with intermittent epigastric discomfort in whom gastroscopy revealed multiple irregular elevated nodular lesions with smooth surfaces at the anterior of the antrum. Surgical resection of the nodular lesions was performed, and the diagnosis of gastritis cystica profunda (GCP) was confirmed by histological examination. Another elevated nodular lesion approximately 10 mm in diameter with an ulcer was found on the gastric side of the remnant stomach near the resection side from 6 to 24 months after the surgical resection. Endoscopic ultrasonography (EUS) and repeated biopsies of the new elevated lesion were performed. Homogeneous, anechoic masses originating from the submucosa without gastric adenocarcinoma in histological examination showed GCP recurrence may occur. Conclusions We report a case of GCP recurrence within 6 months after surgical resection. GCP should be considered in the differential diagnosis of elevated lesions in the stomach. PMID:24885818

Mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogels

DOEpatents

Worsley, Marcus A; Baumann, Theodore F; Satcher, Jr., Joe H

2014-04-01

A method of making a mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogel, including the steps of dispersing nanotubes in an aqueous media or other media to form a suspension, adding reactants and catalyst to the suspension to create a reaction mixture, curing the reaction mixture to form a wet gel, drying the wet gel to produce a dry gel, and pyrolyzing the dry gel to produce the mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogel. The aerogel is mechanically robust, electrically conductive, and ultralow-density, and is made of a porous carbon material having 5 to 95% by weight carbon nanotubes and 5 to 95% carbon binder.

Mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogels

DOEpatents

Worsley, Marcus A.; Baumann, Theodore F.; Satcher, Jr, Joe H.

2016-07-05

A method of making a mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogel, including the steps of dispersing nanotubes in an aqueous media or other media to form a suspension, adding reactants and catalyst to the suspension to create a reaction mixture, curing the reaction mixture to form a wet gel, drying the wet gel to produce a dry gel, and pyrolyzing the dry gel to produce the mechanically robust, electrically conductive ultralow-density carbon nanotube-based aerogel. The aerogel is mechanically robust, electrically conductive, and ultralow-density, and is made of a porous carbon material having 5 to 95% by weight carbon nanotubes and 5 to 95% carbon binder.

Ultralow chirp photonic crystal fiber Mach-Zehnder interferometer.

PubMed

Carvalho, William O F; Spadoti, Danilo H; Silvestre, Enrique; Beltran-Mejia, Felipe

2018-05-20

A photonic crystal fiber Mach-Zehnder interferometer design was optimized to obtain high performance and ultralow chirp. Two long-period gratings were used to excite the cladding modes, and the rich structure of the cladding was tailored to obtain a slightly chirped free spectral range, as required by the Telecommunication Standardization Sector of the International Telecommunication Union (ITU-T) Norm G.694.1. Finally, a fabrication tolerance analysis was performed. The advantages of the proposed device are an ultralow chirp, high bandwidth, and fabrication robustness tolerance.

Memory loss and memory reorganization patterns in temporal lobe epilepsy patients undergoing anterior temporal lobe resection, as demonstrated by pre-versus post-operative functional MRI.

PubMed

Limotai, Chusak; McLachlan, Richard S; Hayman-Abello, Susan; Hayman-Abello, Brent; Brown, Suzan; Bihari, Frank; Mirsattari, Seyed M

2018-06-19

This study was aimed to longitudinally assess memory function and whole-brain memory circuit reorganization in patients with temporal lobe epilepsy (TLE) by comparing activation potentials before versus after anterior temporal lobe (ATL) resection. Nineteen patients with medically-intractable TLE (10 left TLE, 9 right TLE) and 15 healthy controls were enrolled. Group analyses were conducted pre- and post-ATL of a novelty complex scene-encoding paradigm comparing areas of blood oxygen-level-dependent (BOLD) signal activations on functional magnetic resonance imaging (fMRI). None of the pre-operative patient characteristics we studied predicted the extent of pre- to post-operative memory loss. On fMRI, extra-temporal activations were detected pre-operatively in both LTLE and RTLE, particularly in the frontal lobe. Greater activations also were noted in the contralateral hippocampus and parahippocampus in both groups. Performing within-subject comparisons, post-op relative to pre-op, pronounced ipsilateral activations were identified in the left parahippocampal gyrus in LTLE, versus the right middle temporal gyrus in RTLE patients. Memory function was impaired pre-operatively but declined after ATL resection in both RTLE and LTLE patients. Post-operative fMRI results indicate possible functional adaptations to ATL loss, primarily occurring within the left parahippocampal gyrus versus right middle temporal gyrus in LTLE versus RTLE patients, respectively. Copyright © 2018 Elsevier Ltd. All rights reserved.

J-pouch vs. side-to-end anastomosis after hand-assisted laparoscopic low anterior resection for rectal cancer: A prospective randomized trial on short and long term outcomes including life quality and functional results.

PubMed

Okkabaz, Nuri; Haksal, Mustafa; Atici, Ali Emre; Altuntas, Yunus Emre; Gundogan, Ersin; Gezen, Fazli Cem; Oncel, Mustafa

2017-11-01

To analyze the outcomes of j-pouch and side-to-end anastomosis in rectal cancer patients treated with laparoscopic hand-assisted low anterior resection. Prospective trial on cases randomized to have a colonic j-pouch or a side-to-end anastomosis after low anterior resection. Demographics, characteristics of disease and treatment, perioperative results, and functional outcomes and life quality were compared between the groups. Seventy four patients were randomized. Reservoir creation was withdrawn in 17 (23%) patients, mostly related to reach problem (n = 11, 64.7%). Anastomotic leakage rate was significantly higher in j-pouch group (8 [27.6%] vs. 0, p = 0.004). Stoma closure could not be achieved in 16 (28.1%) patients. Life quality and functional outcomes, measured 4, 8 and 12 months after the stoma reversal, were similar. Colonic j-pouch and side-to-end anastomosis are similar regarding perioperative measures including operation time, rates of postoperative complications, reoperation and 30-day mortality, and hospitalization period except anastomotic leak rate, which is higher in j-pouch group. Postoperative aspects are not different in patients receiving either technique including functional outcomes and life quality for the first year after stoma closure. In our opinion, both techniques may be preferred during the daily practice while performing laparoscopic surgery; but surgeons may be aware of a possibly higher anastomotic leak rate in case of a j-pouch. Copyright © 2017 IJS Publishing Group Ltd. Published by Elsevier Ltd. All rights reserved.

Avulsion of the direct head of rectus femoris following arthroscopic subspine impingement resection: a case report

PubMed Central

Devitt, Brian M.; Smith, Bjorn; Stapf, Robert; O’Donnell, John M.

2016-01-01

Arthroscopic resection of the anterior inferior iliac spine (AIIS) for subspine impingement has become a relatively common procedure. The AIIS is the origin of the direct head of rectus femoris (dhRF). Previous studies have reported that removal of the contributing portion of the AIIS causing impingement is unlikely to weaken the attachment of the dhRF. The purpose of this article is to report a case of avulsion of the dhRF, following revision hip arthroscopy for the treatment of subspine impingement. A 23-year-old professional footballer underwent revision left hip arthroscopy for the treatment of subspine impingement. 5-mm of bone was resected inferior to the AIIS. Two-weeks post-operatively, he presented with sudden onset, severe left anterior thigh pain following a fall and hyperextension of his left hip. The patient felt a pop over the anterior aspect of his hip. He noticed immediate swelling, severe pain and stiffness. Examination revealed diffuse swelling, 4/5-power on straight-leg-raise, focal tenderness over the AIIS but no palpable gap. MRI confirmed the clinical suspicion of a dhRF avulsion. Given the minimal loss of power and the lack of significant retraction, the patient was treated conservatively. He was instructed to avoid excessive hip extension. He returned to full participation at 3-months. This article highlights a case of avulsion of the dhRF due to a hyperextension injury of the hip following arthroscopic resection of subspinal impingement, a previously unreported complication. Resection of soft and bone from the AIIS may weaken the insertion of the dhRF. Care should be taken during post-operative rehabilitation to avoid trauma and excessive forces on the dhRF tendon, which may lead to rupture. Rehabilitation should be focused on range of motion of the hip. PMID:27026819

Avulsion of the direct head of rectus femoris following arthroscopic subspine impingement resection: a case report.

PubMed

Devitt, Brian M; Smith, Bjorn; Stapf, Robert; O'Donnell, John M

2016-04-01

Arthroscopic resection of the anterior inferior iliac spine (AIIS) for subspine impingement has become a relatively common procedure. The AIIS is the origin of the direct head of rectus femoris (dhRF). Previous studies have reported that removal of the contributing portion of the AIIS causing impingement is unlikely to weaken the attachment of the dhRF. The purpose of this article is to report a case of avulsion of the dhRF, following revision hip arthroscopy for the treatment of subspine impingement. A 23-year-old professional footballer underwent revision left hip arthroscopy for the treatment of subspine impingement. 5-mm of bone was resected inferior to the AIIS. Two-weeks post-operatively, he presented with sudden onset, severe left anterior thigh pain following a fall and hyperextension of his left hip. The patient felt a pop over the anterior aspect of his hip. He noticed immediate swelling, severe pain and stiffness. Examination revealed diffuse swelling, 4/5-power on straight-leg-raise, focal tenderness over the AIIS but no palpable gap. MRI confirmed the clinical suspicion of a dhRF avulsion. Given the minimal loss of power and the lack of significant retraction, the patient was treated conservatively. He was instructed to avoid excessive hip extension. He returned to full participation at 3-months. This article highlights a case of avulsion of the dhRF due to a hyperextension injury of the hip following arthroscopic resection of subspinal impingement, a previously unreported complication. Resection of soft and bone from the AIIS may weaken the insertion of the dhRF. Care should be taken during post-operative rehabilitation to avoid trauma and excessive forces on the dhRF tendon, which may lead to rupture. Rehabilitation should be focused on range of motion of the hip.

Ultralow-k nanoporous organosilicate dielectric films imprinted with dendritic spheres.

PubMed

Lee, Byeongdu; Park, Young-Hee; Hwang, Yong-Taek; Oh, Weontae; Yoon, Jinhwan; Ree, Moonhor

2005-02-01

Integrated circuits that have improved functionality and speed in a smaller package and that consume less power are desired by the microelectronics industry as well as by end users, to increase device performance and reduce costs. The fabrication of high-performance integrated circuits requires the availability of materials with low or ultralow dielectric constant (low-k: k ultralow-k: k ultralow-k nanoporous organosilicate dielectrics from blends of polymethylsilsesquioxane (PMSSQ) precursor with globular ethyl acrylate-terminated polypropylenimine dendrimers, which act as porogens. These dendrimers are found to mix well with the PMSSQ precursor and after their sacrificial thermal decompositions result in closed, spherical pores of <2.0 nm radius with a very narrow distribution even at high loading. This pore size and distribution are the smallest and the narrowest respectively ever achieved in porous spin-on dielectrics. The method therefore successfully delivers low- and ultralow-k PMSSQ dielectric films that should prove very useful in advanced integrated circuits.

Surgical Treatments on Patients with Anterior Cervical Hyperostosis-Derived Dysphagia

PubMed Central

Song, Ah Rom; Byun, Eunjin; Kim, Youngbae; Park, Kwan Ho; Kim, Kyung Lyul

2012-01-01

Anterior cervical hyperostosis may be a cause of dysphagia. For anterior cervical hyperostosis, medical or surgical treatments can be adhibited in view of the causative mechanisms and intensities of dysphagia. We report 3 cases of cervical hyperostosis-derived progressive dysphagia that underwent operation. Radiologic diagnosis and Video Fluoroscopic Swallowing Study were performed on the three patients for evaluation. One had history of recurrent aspiration pneumonia accompanied by weight loss, another complained of dysphagia only when swallowing pills, and the third experienced recurrence symptom with reossification. All patients reported gradual improvement of dysphagia immediately after their cervical osteophytes were resected through the anterior approach. In relation to postoperative improvement, however, they expressed different degrees of satisfaction according to severity of symptoms. Surgical treatment, performed for the anterior cervical hyperostosis-derived dysphagia, can immediately relieve symptoms of difficulty in swallowing. This might especially be considered as an appropriate treatment option for severe dysphagia. PMID:23185741

[A case of neoadjuvant chemotherapy for locally advanced rectal cancer, which had a invasion into the vagina followed by curative resection].

PubMed

Kimura, Kei; Kagawa, Yoshinori; Kato, Takeshi; Ishida, Tomo; Morimoto, Yoshihiro; Matusita, Katsunori; Kusama, Hiroki; Hashimoto, Tadayoshi; Katura, Yoshiteru; Nitta, Kanae; Takeno, Atushi; Nakahira, Shin; Okishiro, Masatsugu; Sakisaka, Hideki; Taniguchi, Hirokazu; Egawa, Chiyomi; Takeda, Yutaka; Tamura, Shigeyuki

2014-11-01

A-64-years-old woman with locally advanced rectal cancer, which had invaded the vagina, was referred to our hospital. She was administered neoadjuvant chemotherapy to reduce the tumor size. After 4 courses of chemotherapy consisting of folinic acid, fluorouracil, and oxaliplatin (mFOLFOX6), an enhanced computed tomography (CT) scan and magnetic resonance imaging (MRI) indicated marked tumor shrinkage. We performed a laparoscopically assisted low anterior resection, which included total mesorectal resection, resection of the vaginal posterior wall, and right lateral lymph node resection. The chemotherapy prevented us from having to create a permanent colostomy. The efficacy of the neoadjuvant chemotherapy was Grade 1b. We experienced a case of neoadjuvant chemotherapy followed by curative resection.

Ultra-Low Loss Waveguides with Application to Photonic Integrated Circuits

NASA Astrophysics Data System (ADS)

Bauters, Jared F.

The integration of photonic components using a planar platform promises advantages in cost, size, weight, and power consumption for optoelectronic systems. Yet, the typical propagation loss of 5-10 dB/m in a planar silica waveguide is nearly five orders-of-magnitude larger than that in low loss optical fibers. For some applications, the miniaturization of the photonic system and resulting smaller propagation lengths from integration are enough to overcome the increase in propagation loss. For other more demanding systems or applications, such as those requiring long optical time delays or high-quality-factor (Q factor) resonators, the high propagation loss can degrade system performance to a degree that trumps the potential advantages offered by integration. Thus, the reduction of planar waveguide propagation loss in a Si3-N4 based waveguide platform is a primary focus of this dissertation. The ultra-low loss stoichiometric Si3-N4 waveguide platform offers the additional advantages of fabrication process stability and repeatability. Yet, active devices such as lasers, amplifiers, and photodetectors have not been monolithically integrated with ultra-low loss waveguides due to the incompatibility of the active and ultra-low loss processing thermal budgets (ultra-low loss waveguides are annealed at temperatures exceeding 1000 °C in order to drive out impurities). So a platform that enables the integration of active devices with the ultra-low losses of the Si3- N4 waveguide platform is this dissertation's second focus. The work enables the future fabrication of sensor, gyroscope, true time delay, and low phase noise oscillator photonic integrated circuits.

Systolic Anterior Motion of the Mitral Valve after Mitral Valve Repair

PubMed Central

Sternik, Leonid; Zehr, Kenton J.

2005-01-01

Factors predisposing patients to systolic anterior motion of the mitral valve (SAM) with left ventricular outflow tract (LVOT) obstruction after mitral valve repair are the presence of a myxomatous mitral valve with redundant leaflets, a nondilated hyperdynamic left ventricle, and a short distance between the mitral valve coaptation point and the ventricular septum after repair. From December 1999 through March 2000, we used our surgical method in 6 patients with severely myxomatous regurgitant mitral valves who were at risk of developing SAM. Leaflets were markedly redundant in all 6. Left ventricular function was hyperdynamic in 4 patients and normal in 2. Triangular or quadrangular resection of the midportion of the posterior leaflet and posterior band annuloplasty were performed. To prevent SAM and LVOT obstruction, extra, posteriorly directed, mid-posterior-leaflet secondary chordae tendineae, which would otherwise have been resected, were transferred to the underside of the middle of the mid-anterior leaflet with a small piece of associated valve as an anchoring pledget. This kept the redundant anterior leaflet edge, which extended below the coaptation point, away from the LVOT. No post-repair SAM or LVOT obstruction was observed on intraoperative or discharge echocardiography. All patients had no or trivial residual mitral regurgitation. We conclude that extra chordae tendineae, when available, can be used in mitral valve repair to tether the redundant anterior leaflet and thus prevent it from flipping into the LVOT. This will theoretically prevent SAM and LVOT obstruction in patients with risk factors for SAM. PMID:15902821

[Dilemmas and controversies related to cancers of the anterior laryngeal commissure].

PubMed

Djukić, V; Stanković, P; Stevandić, N; Janosević, Lj; Pavlović, B

2004-01-01

From diagnostic and therapeutical aspect, the cancers of the anterior laryngeal commissure are the separate category in glottic cancers. But, they have not been individually classified in the majority of statistical reports, and, therefore, the incidence of the anterior commissural cancer should be taken with precaution. The issue of therapeutical strategy is controversial, considering the options and limitations of resections of the anterior commissural tumors, within the conception of oncological radicalism. Dilemmas are being especially faced with in radiotherapy, given the failures and unsatisfactory radiotherapeutical results. The prospective clinical study included the analysis of the incidence of primary and secondary cancers of the anterior commissure of the larynx. The follow-up of five-year survivals allowed for the establishment of efficiency of the applied therapeutical methods. The results of five-year survival in patients treated by primary surgery were highly more significant in relation to results obtained by radiotherapy of patients.

Squid detected NMR and MRI at ultralow fields

DOEpatents

Clarke, John [Berkeley, CA; McDermott, Robert [Louisville, CO; Pines, Alexander [Berkeley, CA; Trabesinger, Andreas Heinz [CH-8006 Zurich, CH

2007-05-15

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

Squid detected NMR and MRI at ultralow fields

DOEpatents

Clarke, John; McDermott, Robert; Pines, Alexander; Trabesinger, Andreas Heinz

2006-05-30

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

Squid detected NMR and MRI at ultralow fields

DOEpatents

Clarke, John [Berkeley, CA; Pines, Alexander [Berkeley, CA; McDermott, Robert F [Monona, WI; Trabesinger, Andreas H [London, GB

2008-12-16

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

SQUID detected NMR and MRI at ultralow fields

DOEpatents

Clarke, John; McDermott, Robert; Pines, Alexander; Trabesinger, Andreas Heinz

2006-10-03

Nuclear magnetic resonance (NMR) signals are detected in microtesla fields. Prepolarization in millitesla fields is followed by detection with an untuned dc superconducting quantum interference device (SQUID) magnetometer. Because the sensitivity of the SQUID is frequency independent, both signal-to-noise ratio (SNR) and spectral resolution are enhanced by detecting the NMR signal in extremely low magnetic fields, where the NMR lines become very narrow even for grossly inhomogeneous measurement fields. MRI in ultralow magnetic field is based on the NMR at ultralow fields. Gradient magnetic fields are applied, and images are constructed from the detected NMR signals.

Ultra-low dose naltrexone attenuates chronic morphine-induced gliosis in rats.

PubMed

Mattioli, Theresa-Alexandra M; Milne, Brian; Cahill, Catherine M

2010-04-16

The development of analgesic tolerance following chronic morphine administration can be a significant clinical problem. Preclinical studies demonstrate that chronic morphine administration induces spinal gliosis and that inhibition of gliosis prevents the development of analgesic tolerance to opioids. Many studies have also demonstrated that ultra-low doses of naltrexone inhibit the development of spinal morphine antinociceptive tolerance and clinical studies demonstrate that it has opioid sparing effects. In this study we demonstrate that ultra-low dose naltrexone attenuates glial activation, which may contribute to its effects on attenuating tolerance. Spinal cord sections from rats administered chronic morphine showed significantly increased immuno-labelling of astrocytes and microglia compared to saline controls, consistent with activation. 3-D images of astrocytes from animals administered chronic morphine had significantly larger volumes compared to saline controls. Co-injection of ultra-low dose naltrexone attenuated this increase in volume, but the mean volume differed from saline-treated and naltrexone-treated controls. Astrocyte and microglial immuno-labelling was attenuated in rats co-administered ultra-low dose naltrexone compared to morphine-treated rats and did not differ from controls. Glial activation, as characterized by immunohistochemical labelling and cell size, was positively correlated with the extent of tolerance developed. Morphine-induced glial activation was not due to cell proliferation as there was no difference observed in the total number of glial cells following chronic morphine treatment compared to controls. Furthermore, using 5-bromo-2-deoxyuridine, no increase in spinal cord cell proliferation was observed following chronic morphine administration. Taken together, we demonstrate a positive correlation between the prevention of analgesic tolerance and the inhibition of spinal gliosis by treatment with ultra-low dose naltrexone

Laparoscopic discoid anterior rectal excision with the circular stapler for rectosigmoid endometriosis, performed by the gynecologic surgeon.

PubMed

Zanatta, Alysson; Sousa, Jânio S; Machado, Ricardo L; Polcheira, Paulo A

2015-01-01

To demonstrate the technique of laparoscopic discoid anterior rectal wall resection using a circular stapler, feasible in the case of rectosigmoid endometriosis lesions measuring ≤ 3 cm. Case report (Canadian Task Force classification III). Private practice hospital in São Paulo, Brazil. Thirty-four-year-old woman with pelvic deep endometriosis including a 2-cm lesion in the rectosigmoid situated 11 cm proximally to the anal border. She had chronic pelvic pain, dysmenorrhea, dyspareunia, and constipation. She had undergone no previous surgical procedures. Standard 4-puncture laparoscopy was performed, and all visible endometriosis lesions were first removed before proceeding to rectal resection. The avascular rectovaginal space was identified, and the rectosigmoid was mobilized cranially, releasing the vagina and increasing the final distance of the bowel anastomosis to the anal border. The rectosigmoid nodule was isolated in its entire circumference and remained restricted to the anterior wall of the bowel. It was then transfixed using a 2-0 polyglycolic suture, with the healthy proximal and distal limits of the bowel included in the suture. A 33-cm endoscopic circular stapler was introduced via the anus up to the distal limit of the lesion and opened inside the bowel lumen. By pulling the edges of the suture, the rectosigmoid nodule was introduced inside of the circular stapler. It was fired to resect the anterior rectal wall, and the anastomosis was situated at the anterior and lateral walls of the bowel. Integrity of the bowel was checked via infusion of saline solution with methylene blue dye. Gynecologic surgeons performed all of the procedures. Bowel resection took 20 minutes, and the entire surgical procedure lasted 120 minutes. The patient was discharged after 48 hours. There were no intercurrent events, either early or late postoperatively. The patient was symptom-free at 2 years of follow-up. Laparoscopic discoid excision of an anterior rectal nodule

Ultra-low temperature curable nano-silver conductive adhesive for piezoelectric composite material

NASA Astrophysics Data System (ADS)

Yan, Chao; Liao, Qingwei; Zhou, Xingli; Wang, Likun; Zhong, Chao; Zhang, Di

2018-01-01

Limited by the low thermal resistance of composite material, ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conduction treatment of piezoelectric composite material. An ultra-low temperature curable nano-silver conductive adhesive with high adhesion strength for the applications of piezoelectric composite material was investigated. The crystal structure of cured adhesive, SEM/EDS analysis, thermal analysis, adhesive properties and conductive properties of different content of nano-silver filler or micron-silver doping samples were studied. The results show that with 60 wt.% nano-silver filler the ultra-low temperature curable conductive silver adhesive had the relatively good conductivity as volume resistivity of 2.37 × 10-4 Ω cm, and good adhesion strength of 5.13 MPa. Minor micron-doping (below 15 wt.%) could improve conductivity, but would decrease other properties. The ultra-low temperature curable nano-silver conductive adhesive could successfully applied to piezoelectric composite material.

Measurement of knee joint gaps without bone resection: "physiologic" extension and flexion gaps in total knee arthroplasty are asymmetric and unequal and anterior and posterior cruciate ligament resections produce different gap changes.

PubMed

Nowakowski, Andrej Maria; Majewski, Martin; Müller-Gerbl, Magdalena; Valderrabano, Victor

2012-04-01

General agreement is that flexion and extension gaps should be equal and symmetrical in total knee arthroplasty (TKA) procedures. However, comparisons using a standard TKA approach to normal knee joints that have not undergone bone resection are currently unavailable. Since bony preparation can influence capsule and ligament tension, our purpose was to perform measurements without this influence. Ten normal cadaveric knees were assessed using a standard medial parapatellar TKA approach with patellar subluxation. Gap measurements were carried out twice each alternating 100 and 200 N per compartment using a prototypical force-determining ligament balancer without the need for bony resection. Initial measurements were performed in extension, followed by 908 of flexion. The ACL was then resected, and finally the PCL was resected, and measurements were carried out in an analogous fashion. In general, the lateral compartment could be stretched further than the medial compartment, and the corresponding flexion gap values were significantly larger. ACL resection predominantly increased extension gaps, while PCL resection increased flexion gaps. Distraction force of 100 N per compartment appeared adequate; increasing to 200 N did not improve the results.

Ultralow thermal conductivity in all-inorganic halide perovskites

PubMed Central

Li, Huashan; Wong, Andrew B.; Zhang, Dandan; Lai, Minliang; Yu, Yi; Kong, Qiao; Lin, Elbert; Urban, Jeffrey J.; Grossman, Jeffrey C.; Yang, Peidong

2017-01-01

Controlling the flow of thermal energy is crucial to numerous applications ranging from microelectronic devices to energy storage and energy conversion devices. Here, we report ultralow lattice thermal conductivities of solution-synthesized, single-crystalline all-inorganic halide perovskite nanowires composed of CsPbI3 (0.45 ± 0.05 W·m−1·K−1), CsPbBr3 (0.42 ± 0.04 W·m−1·K−1), and CsSnI3 (0.38 ± 0.04 W·m−1·K−1). We attribute this ultralow thermal conductivity to the cluster rattling mechanism, wherein strong optical–acoustic phonon scatterings are driven by a mixture of 0D/1D/2D collective motions. Remarkably, CsSnI3 possesses a rare combination of ultralow thermal conductivity, high electrical conductivity (282 S·cm−1), and high hole mobility (394 cm2·V−1·s−1). The unique thermal transport properties in all-inorganic halide perovskites hold promise for diverse applications such as phononic and thermoelectric devices. Furthermore, the insights obtained from this work suggest an opportunity to discover low thermal conductivity materials among unexplored inorganic crystals beyond caged and layered structures. PMID:28760988

Ultralow thermal conductivity in all-inorganic halide perovskites.

PubMed

Lee, Woochul; Li, Huashan; Wong, Andrew B; Zhang, Dandan; Lai, Minliang; Yu, Yi; Kong, Qiao; Lin, Elbert; Urban, Jeffrey J; Grossman, Jeffrey C; Yang, Peidong

2017-08-15

Controlling the flow of thermal energy is crucial to numerous applications ranging from microelectronic devices to energy storage and energy conversion devices. Here, we report ultralow lattice thermal conductivities of solution-synthesized, single-crystalline all-inorganic halide perovskite nanowires composed of CsPbI 3 (0.45 ± 0.05 W·m -1 ·K -1 ), CsPbBr 3 (0.42 ± 0.04 W·m -1 ·K -1 ), and CsSnI 3 (0.38 ± 0.04 W·m -1 ·K -1 ). We attribute this ultralow thermal conductivity to the cluster rattling mechanism, wherein strong optical-acoustic phonon scatterings are driven by a mixture of 0D/1D/2D collective motions. Remarkably, CsSnI 3 possesses a rare combination of ultralow thermal conductivity, high electrical conductivity (282 S·cm -1 ), and high hole mobility (394 cm 2 ·V -1 ·s -1 ). The unique thermal transport properties in all-inorganic halide perovskites hold promise for diverse applications such as phononic and thermoelectric devices. Furthermore, the insights obtained from this work suggest an opportunity to discover low thermal conductivity materials among unexplored inorganic crystals beyond caged and layered structures.

Outcomes of asymptomatic anastomotic leaks found on routine postoperative water-soluble enema following anterior resection for cancer.

PubMed

Killeen, S; Souroullas, P; Ho Tin, H; Hunter, I A; O'Grady, H; Gunn, J; Hartley, J E

2013-11-01

The incidence and consequence of an anastomotic leak associated with low anterior resection for cancer mandates covering stoma in most cases. A water-soluble enema is often performed to assess anastomotic integrity prior to stoma reversal. The functional outcome following reversal in patients with occult radiologically detected leaks is poorly defined. The goal of the present study was to determine the functional outcome in patients with a radiologically detected anastomotic leak who subsequently underwent stoma reversal. This case control study used patients with and without radiologically detected occult anastomotic leak having undergone reversal of covering stomata. The study group was matched with controls for age, gender, procedure, tumor stage, and adjuvant/neoadjuvant therapy. Validated fecal incontinence quality of life (FIQL), Cleveland Clinic Fecal Incontinence Score (CCFIS), and the Memorial Sloan-Kettering Cancer Center (MSKCC) Bowel Function Index (BFI) were used. Patient satisfaction, medication use, and ancillary procedures prior to closure were also recorded. Thirteen patients with radiologically detected occult anastomotic leaks and 13 matched controls were identified from a prospectively maintained database. The FIQL, CCFIS, and MSKCC BFI scores were significantly reduced in those with occult leaks. The mean number of radiological and surgical interventions was significantly greater in the patients with occult leaks. Antidiarrheal and bulking agent use, as well as patient satisfaction, were the same for both groups. Only one patient in the occult leak group would not undergo stoma reversal again. Reversal of a defunctioning ileostomy in the presence of an occult radiological leak can be associated with poorer functional outcomes, but patient satisfaction is undiminished.

Huge mediastinal liposarcoma resected by clamshell thoracotomy: a case report.

PubMed

Toda, Michihito; Izumi, Nobuhiro; Tsukioka, Takuma; Komatsu, Hiroaki; Okada, Satoshi; Hara, Kantaro; Ito, Ryuichi; Shibata, Toshihiko; Nishiyama, Noritoshi

2017-12-01

Liposarcoma is the single most common soft tissue sarcoma. Because mediastinal liposarcomas often grow rapidly and frequently recur locally despite adjuvant chemotherapy and radiotherapy, they require complete excision. Therefore, the feasibility of achieving complete surgical excision must be carefully considered. We here report a case of a huge mediastinal liposarcoma resected via clamshell thoracotomy. A 64-year-old man presented with dyspnea on effort. Cardiomegaly had been diagnosed 6 years previously, but had been left untreated. A computed tomography scan showed a huge (36 cm diameter) anterior mediastinal tumor expanding into the pleural cavities bilaterally. The tumor comprised mostly fatty tissue but contained two solid areas. Echo-guided needle biopsies were performed and a diagnosis of an atypical lipomatous tumor was established by pathological examination of the biopsy samples. Surgical resection was performed via a clamshell incision, enabling en bloc resection of this huge tumor. Although there was no invasion of surrounding organs, the left brachiocephalic vein was resected because it was circumferentially surrounded by tumor and could not be preserved. The tumor weighed 3500 g. Pathologic examination of the resected tumor resulted in a diagnosis of a biphasic tumor comprising dedifferentiated liposarcoma and non-adipocytic sarcoma with necrotic areas. The patient remains free of recurrent tumor 20 months postoperatively. Clamshell incision provides an excellent surgical field and can be performed safely in patients with huge mediastinal liposarcomas.

Modified single stapler technique in anterior resection for rectal cancer.

PubMed

Akbaba, Soner; Ersoy, Pamir Eren; Gundogdu, Riza Haldun; Ulas, Murat; Menekse, Ebru

2015-01-01

Technical difficulties during colorectal surgery increase the complication rates. We introduce a modified single stapler technique for patients in whom technical problems are encountered while performing double stapler technique. Before pelvic dissection, descending colon is divided at minimum 10 cm proximal to the tumoral segment. Tumor specific mesorectal excision is performed and two purse string sutures are placed at the distal margin with an interval of 1 - 2 cm. After introducing a circular stapler via the anus, the distal purse string suture is tied around the central shaft of the stapler and the proximal purse string suture around the colonic lumen. After the resection is completed between the two sutures, the anvil shaft is connected to the central shaft and the stapler is closed and fired. None of the patients had an anastomotic leak. This technique may be a safe alternative particularly in patients with narrow pelvis and distal tumors.

Orbitopterional Craniotomy Resection of Pediatric Suprasellar Craniopharyngioma.

PubMed

LeFever, Devon; Storey, Chris; Guthikonda, Bharat

2018-04-01

The orbitopterional approach provides an excellent combination of basal access and suprasellar access. This approach also allows for less brain retraction when resecting larger suprasellar tumors that are more superiorly projecting due to a more frontal and inferior trajectory. In this operative video, the authors thoroughly detail an orbitopterional craniotomy utilizing a one-piece modified orbitozygomatic technique. This technique involves opening the craniotomy through a standard pterional incision. The craniotomy is performed using the standard three burr holes of a pterional approach; however, the osteotomy is extended anteriorly through the frontal process of the zygomatic bone as well as through the supraorbital rim. In this operative video atlas, the authors illustrate the operative anatomy, as well as surgical strategy and techniques to resect a large suprasellar craniopharyngioma in a 4-year-old male. Other reasonable approach options for a lesion of this size would include a standard pterional approach, a supraorbital approach, or expanded endoscopic transsphenoidal approach. The lesion was quite high and thus, the supraorbital approach may confine access to the superior portion of the tumor. While recognizing that some groups may have chosen the endoscopic expanded transsphenoidal approach for this lesion, the authors describe more confidence in achieving the goal of a safe and maximal resection with the orbitopterional approach. The link to the video can be found at: https://youtu.be/eznsK16BzR8 .

Repeated transsphenoidal surgery for resection of pituitary adenoma.

PubMed

Wang, Shousen; Xiao, Deyong; Wang, Rumi; Wei, Liangfeng; Hong, Jingfang

2015-03-01

To investigate the surgical strategy of repeated microscopic transsphenoidal surgery (TSS) for treatment of pituitary adenoma, surgical techniques and treatment outcomes for 29 patients with pituitary adenoma were reviewed and analyzed. There were 17 patients who underwent TSS 18 times and 12 patients who underwent TSS 13 times. The interval between each TSS ranged from 3 months to 18 years, with a median time of 4 years. The tumor height was 15 to 45 mm on the last surgery. Among the 29 patients, 16 patients underwent total tumor resection, 11 patients underwent subtotal resection, and 2 patients underwent partial resection. Cerebrospinal fluid leak occurred in 10 patients. Among 24 patients who were followed up effectively, 1 patient developed abducens paralysis after surgery, 1 patient had chronic diabetes insipidus, and 1 patient received steroid-dependent alternative treatment. The repeated TSS may present satisfied outcomes in experienced hands. The upper edge of the posterior choanae should be identified to ensure the right orientation. The openings of the anterior wall of the sphenoid sinus and the sellar floor should be appropriately expanded to improve tumor exposure. The artificial materials should be identified and removed carefully. Intraoperative cerebrospinal fluid leakage should be managed well.

Tribological performance of ultra-low viscosity composite base fluid with bio-derived fluid

USDA-ARS?s Scientific Manuscript database

One obvious approach to increase efficiencies in many lubricated systems such as ICE and gearbox is the reduction in viscosity of oil lubricant. Indeed, ultra-low viscosity engine oils are now commercially available. One approach to the development of ultra-low viscosity lubricants without compromis...

Ultralow thermal conductivity in all-inorganic halide perovskites

DOE PAGES

Lee, Woochul; Li, Huashan; Wong, Andrew B.; ...

2017-07-08

Controlling the flow of thermal energy is crucial to numerous applications ranging from microelectronic devices to energy storage and energy conversion devices. Here in this paper, we report ultralow lattice thermal conductivities of solution-synthesized, single-crystalline all-inorganic halide perovskite nanowires composed of CsPbI 3 (0.45 ± 0.05 W·m -1 ·K -1), CsPbBr 3 (0.42 ± 0.04 W·m -1·K -1), and CsSnI 3 (0.38 ± 0.04 W·m -1 ·K -1). We attribute this ultralow thermal conductivity to the cluster rattling mechanism, wherein strong optical–acoustic phonon scatterings are driven by a mixture of 0D/1D/2D collective motions. Remarkably, CsSnI 3 possesses a rare combinationmore » of ultralow thermal conductivity, high electrical conductivity (282 S·cm -1), and high hole mobility (394 cm 2 ·V -1 ·s -1). The unique thermal transport properties in all-inorganic halide perovskites hold promise for diverse applications such as phononic and thermoelectric devices. Furthermore, the insights obtained from this work suggest an opportunity to discover low thermal conductivity materials among unexplored inorganic crystals beyond caged and layered structures.« less

Ultralow thermal conductivity in all-inorganic halide perovskites

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lee, Woochul; Li, Huashan; Wong, Andrew B.

Controlling the flow of thermal energy is crucial to numerous applications ranging from microelectronic devices to energy storage and energy conversion devices. Here in this paper, we report ultralow lattice thermal conductivities of solution-synthesized, single-crystalline all-inorganic halide perovskite nanowires composed of CsPbI 3 (0.45 ± 0.05 W·m -1 ·K -1), CsPbBr 3 (0.42 ± 0.04 W·m -1·K -1), and CsSnI 3 (0.38 ± 0.04 W·m -1 ·K -1). We attribute this ultralow thermal conductivity to the cluster rattling mechanism, wherein strong optical–acoustic phonon scatterings are driven by a mixture of 0D/1D/2D collective motions. Remarkably, CsSnI 3 possesses a rare combinationmore » of ultralow thermal conductivity, high electrical conductivity (282 S·cm -1), and high hole mobility (394 cm 2 ·V -1 ·s -1). The unique thermal transport properties in all-inorganic halide perovskites hold promise for diverse applications such as phononic and thermoelectric devices. Furthermore, the insights obtained from this work suggest an opportunity to discover low thermal conductivity materials among unexplored inorganic crystals beyond caged and layered structures.« less

Anterior trans-frontal endoscopic resection of third-ventricle colloid cyst: how I do it.

PubMed

Nasi, Davide; Iaccarino, Corrado; Romano, Antonio

2017-06-01

The endoscopic technique has been recognised as a viable and safe alternative to microsurgery for the treatment of third-ventricle colloid cyst. However, the standard precoronal endoscopic approach does not always provide an adequate visualisation of the attachment of the cyst to the velum interpositum. Using a more anterior approach, it is easier to reach the roof of the cyst and its possible adherences with the tela choroidea. The authors describe step by step the anterior trans-frontal endoscopic approach for management of third ventricle colloid cyst. The described approach has shown to be safe, quick and effective for the treatment of third-ventricle colloid cyst.

Ultralow concentrations of bupivacaine exert anti-inflammatory effects on inflammation-reactive astrocytes

PubMed Central

Block, Linda; Jörneberg, Per; Björklund, Ulrika; Westerlund, Anna; Biber, Björn; Hansson, Elisabeth

2013-01-01

Bupivacaine is a widely used, local anesthetic agent that blocks voltage-gated Na+ channels when used for neuro-axial blockades. Much lower concentrations of bupivacaine than in normal clinical use, < 10−8 m, evoked Ca2+ transients in astrocytes from rat cerebral cortex, that were inositol trisphosphate receptor-dependent. We investigated whether bupivacaine exerts an influence on the Ca2+ signaling and interleukin-1β (IL-1β) secretion in inflammation-reactive astrocytes when used at ultralow concentrations, < 10−8 m. Furthermore, we wanted to determine if bupivacaine interacts with the opioid-, 5-hydroxytryptamine- (5-HT) and glutamate-receptor systems. With respect to the μ-opioid- and 5-HT-receptor systems, bupivacaine restored the inflammation-reactive astrocytes to their normal non-inflammatory levels. With respect to the glutamate-receptor system, bupivacaine, in combination with an ultralow concentration of the μ-opioid receptor antagonist naloxone and μ-opioid receptor agonists, restored the inflammation-reactive astrocytes to their normal non-inflammatory levels. Ultralow concentrations of bupivacaine attenuated the inflammation-induced upregulation of IL-1β secretion. The results indicate that bupivacaine interacts with the opioid-, 5-HT- and glutamate-receptor systems by affecting Ca2+ signaling and IL-1β release in inflammation-reactive astrocytes. These results suggest that bupivacaine may be used at ultralow concentrations as an anti-inflammatory drug, either alone or in combination with opioid agonists and ultralow concentrations of an opioid antagonist. PMID:24083665

A method for safely resecting anterior butterfly gliomas: the surgical anatomy of the default mode network and the relevance of its preservation.

PubMed

Burks, Joshua D; Bonney, Phillip A; Conner, Andrew K; Glenn, Chad A; Briggs, Robert G; Battiste, James D; McCoy, Tressie; O'Donoghue, Daniel L; Wu, Dee H; Sughrue, Michael E

2017-06-01

OBJECTIVE Gliomas invading the anterior corpus callosum are commonly deemed unresectable due to an unacceptable risk/benefit ratio, including the risk of abulia. In this study, the authors investigated the anatomy of the cingulum and its connectivity within the default mode network (DMN). A technique is described involving awake subcortical mapping with higher attention tasks to preserve the cingulum and reduce the incidence of postoperative abulia for patients with so-called butterfly gliomas. METHODS The authors reviewed clinical data on all patients undergoing glioma surgery performed by the senior author during a 4-year period at the University of Oklahoma Health Sciences Center. Forty patients were identified who underwent surgery for butterfly gliomas. Each patient was designated as having undergone surgery either with or without the use of awake subcortical mapping and preservation of the cingulum. Data recorded on these patients included the incidence of abulia/akinetic mutism. In the context of the study findings, the authors conducted a detailed anatomical study of the cingulum and its role within the DMN using postmortem fiber tract dissections of 10 cerebral hemispheres and in vivo diffusion tractography of 10 healthy subjects. RESULTS Forty patients with butterfly gliomas were treated, 25 (62%) with standard surgical methods and 15 (38%) with awake subcortical mapping and preservation of the cingulum. One patient (1/15, 7%) experienced postoperative abulia following surgery with the cingulum-sparing technique. Greater than 90% resection was achieved in 13/15 (87%) of these patients. CONCLUSIONS This study presents evidence that anterior butterfly gliomas can be safely removed using a novel, attention-task based, awake brain surgery technique that focuses on preserving the anatomical connectivity of the cingulum and relevant aspects of the cingulate gyrus.

Craniofacial resection and its role in the management of sinonasal malignancies.

PubMed

Taghi, Ali; Ali, Ahmed; Clarke, Peter

2012-09-01

Sinonasal malignancy is rare, and its presentation is commonly late. There is a wide variety of pathologies with varying natural histories and survival rates. Anatomy of the skull base is extremely complex and tumors are closely related to orbits, frontal lobes and cavernous sinus. Anatomical detail and the late presentation render surgical management a challenging task. A thorough understanding of anatomy and pathology combined with modern neuroimaging and reliable reconstruction within a multidisciplinary team is imperative to carry out skull base surgery effectively. While endoscopic approaches are gaining credibility, clearly, it will be some time before meaningful comparisons with craniofacial resection can be made. Until then, craniofacial resection will remain the gold standard for managing the sinonasal malignancies of the anterior skull base, as it has proved to be safe and effective.

Ultralow field NMR spectrometer with an atomic magnetometer near room temperature

NASA Astrophysics Data System (ADS)

Liu, Guobin; Li, Xiaofeng; Sun, Xianping; Feng, Jiwen; Ye, Chaohui; Zhou, Xin

2013-12-01

We present a Cs atomic magnetometer with a sensitivity of 150 fT/Hz1/2 operating near room temperature. The nuclear magnetic resonance (NMR) signal of 125 μL tap water was detected at an ultralow magnetic field down to 47 nT, with the signal-to-noise ratio (SNR) of the NMR signal approaching 50 after eight averages. Relaxivity experiments with a Gd(DTPA) contrast agent in zero field were performed, in order to show the magnetometer's ability to measure spin-lattice relaxation time with high accuracy. This demonstrates the feasibility of an ultralow field NMR spectrometer based on a Cs atomic magnetometer, which has a low working temperature, short data acquisition time and high sensitivity. This kind of NMR spectrometer has great potential in applications such as chemical analysis and magnetic relaxometry detection in ultralow or zero fields.

Symptomatic Cerebral Vasospasm and Delayed Cerebral Ischemia Following Transsphenoidal Resection of a Craniopharyngioma.

PubMed

Ricarte, Irapuá Ferreira; Funchal, Bruno F; Miranda Alves, Maramélia A; Gomes, Daniela L; Valiente, Raul A; Carvalho, Flávio A; Silva, Gisele S

2015-09-01

Vasospasm has been rarely described as a complication associated with craniopharyngioma surgery. Herein we describe a patient who developed symptomatic vasospasm and delayed cerebral ischemia after transsphenoidal surgery for a craniopharyngioma. A 67-year-old woman became drowsy 2 weeks after a transsphenoidal resection of a craniopharyngioma. A head computed tomography (CT) was unremarkable except for postoperative findings. Electroencephalogram and laboratory studies were within the normal limits. A repeated CT scan 48 hours after the initial symptoms showed bilateral infarcts in the territory of the anterior cerebral arteries (ACA). Transcranial Doppler (TCD) showed increased blood flow velocities in both anterior cerebral arteries (169 cm/second in the left ACA and 145 cm/second in the right ACA) and right middle cerebral artery (164 cm/second) compatible with vasospasm. A CT angiography confirmed the findings. She was treated with induced hypertension and her level of consciousness improved. TCD velocities normalized after 2 weeks. Cerebral vasospasm should be considered in the differential diagnosis of patients with altered neurologic status in the postoperative period following a craniopharyngioma resection. Copyright © 2015 National Stroke Association. Published by Elsevier Inc. All rights reserved.

High-power all-fiber ultra-low noise laser

NASA Astrophysics Data System (ADS)

Zhao, Jian; Guiraud, Germain; Pierre, Christophe; Floissat, Florian; Casanova, Alexis; Hreibi, Ali; Chaibi, Walid; Traynor, Nicholas; Boullet, Johan; Santarelli, Giorgio

2018-06-01

High-power ultra-low noise single-mode single-frequency lasers are in great demand for interferometric metrology. Robust, compact all-fiber lasers represent one of the most promising technologies to replace the current laser sources in use based on injection-locked ring resonators or multi-stage solid-state amplifiers. Here, a linearly polarized high-power ultra-low noise all-fiber laser is demonstrated at a power level of 100 W. Special care has been taken in the study of relative intensity noise (RIN) and its reduction. Using an optimized servo actuator to directly control the driving current of the pump laser diode, we obtain a large feedback bandwidth of up to 1.3 MHz. The RIN reaches - 160 dBc/Hz between 3 and 20 kHz.

Background characterization of an ultra-low background liquid scintillation counter

DOE PAGES

Erchinger, J. L.; Orrell, John L.; Aalseth, C. E.; ...

2017-01-26

The Ultra-Low Background Liquid Scintillation Counter developed by Pacific Northwest National Laboratory will expand the application of liquid scintillation counting by enabling lower detection limits and smaller sample volumes. By reducing the overall count rate of the background environment approximately 2 orders of magnitude below that of commercially available systems, backgrounds on the order of tens of counts per day over an energy range of ~3–3600 keV can be realized. Finally, initial test results of the ULB LSC show promising results for ultra-low background detection with liquid scintillation counting.

Finite element analysis for edge-to-edge technique to treat post-mitral valve repair systolic anterior motion.

PubMed

Zhong, Qi; Zeng, Wenhua; Huang, Xiaoyang; Zhao, Xiaojia

2014-01-01

Systolic anterior motion of the mitral valve is an uncommon complication of mitral valve repair, which requires immediate supplementary surgical action. Edge-to-edge suture is considered as an effective technique to treat post-mitral valve repair systolic anterior motion by clinical researchers. However, the fundamentals and quantitative analysis are vacant to validate the effectiveness of the additional edge-to-edge surgery to repair systolic anterior motion. In the present work, finite element models were developed to simulate a specific clinical surgery for patients with posterior leaflet prolapse, so as to analyze the edge-to-edge technique quantificationally. The simulated surgery procedure concluded several actions such as quadrangular resection, mitral annuloplasty and edge-to-edge suture. And the simulated results were compared with echocardiography and measurement data of the patients under the mitral valve surgery, which shows good agreement. The leaflets model with additional edge-to-edge suture has a shorter mismatch length than that of the model merely under quadrangular resection and mitral annuloplasty actions at systole, which assures a better coaptation status. The stress on the leaflets after edge-to-edge suture is lessened as well.

[Anterior skull-base schwannoma].

PubMed

Esquivel-Miranda, Miguel; De la O Ríos, Elier; Vargas-Valenciano, Emmanuelle; Moreno-Medina, Eva

Schwannomas are nerve sheath tumours that originate in Schwann cells. They are usually solitary and sporadic and manifest on peripheral, spinal or cranial nerves. Intracranial schwannomas tend to manifest on the eighth cranial nerve, particularly in patients with neurofibromatosis type2. Anterior skull-base schwannomas represent less than 1% of all intracranial schwannomas. They are more frequent in young people and are typically benign. These tumours represent a diagnostic challenge due to their rarity and difficult differential diagnosis, and numerous theories have been postulated concerning their origin and development. In this article, we present the case of a 13-year-old male with a single anterior cranial-base tumour not associated with neurofibromatosis who presented with headache, papilloedema, eye pain and loss of visual acuity. Complete resection of the tumour was performed, which was histopathologically diagnosed as a schwannoma. The patient made a complete clinical recovery with abatement of all symptoms. We conducted a review of the literature and found 66 cases worldwide with this diagnosis. We describe the most relevant epidemiological and clinical characteristics of this kind of tumour and its relation with the recently discovered and similar olfactory schwannoma. Copyright © 2017 Sociedad Española de Neurocirugía. Publicado por Elsevier España, S.L.U. All rights reserved.

Permanent anosmia and ageusia after resection of a left temporoinsular low-grade glioma: anatomofunctional considerations.

PubMed

Ribas, Eduardo Santamaria Carvalhal; Duffau, Hugues

2012-05-01

Five percent of the general population has olfactory or gustatory disorders, although most do not complain about it. However, in some cases, these symptoms can be disabling and may affect quality of life. Anosmia was reported as a possible complication following head injury and neurosurgical procedures, particularly after the resection of tumors located in the anterior fossa and the treatment of aneurysms in the anterior circulation. Nonetheless, in all of these situations, olfactory dysfunction could be explained by damage to the peripheral olfactory system. Here, the authors report a case of complete anosmia associated with ageusia following awake resection of a low-grade glioma involving the left temporoinsular region, with no recovery during a follow-up of 3 years. The frontal lobe was not retracted, and the olfactory tract was not visualized during surgery; therefore, postoperative anosmia and ageusia are likely explained by damage to the cortex and central pathways responsible for these senses. The authors suggest that the patient might have had a subclinical right hemianosmia before surgery, which is a common condition. After resection of the central structures critical for smell and taste processing in the left hemisphere, the patient could have finally had bilateral and complete olfactory and gustatory loss. This is the first known report of permanent anosmia and ageusia following glioma surgery. Because these symptoms might have been underestimated, more attention should be devoted to olfaction and taste, especially with regard to possible subclinical preoperative deficit.

Resection of recurrent branchial cleft deformity using selective neck dissection technique.

PubMed

Cai, Qian; Pan, Yong; Xu, Yaodong; Liang, Faya; Huang, Xiaoming; Jiang, Xiaoyu; Han, Ping

2014-07-01

This study explores application of selective neck dissection technique in recurrent second, third, and fourth branchial cleft deformities. A total of 19 cases of recurrent second, third, and fourth branchial cleft deformities were treated using the selective neck dissection technique, during which the sternocleidomastoid muscle, cervical anterior muscle, and carotid sheath were contoured. The lesion above the prevertebral fascia was then resected en bloc. Finally, the opening of the internal fistula was ligated and sutured using the purse-string approach. Patients in this study had no injures to their internal carotid artery, jugular vein, vagus nerve, accessory nerve, hypoglossal nerve, or recurrent laryngeal nerve. There were also no complications such as poor wound healing. The patients were monitored for 7-73 months and showed no recurrences. Using selective neck dissection to treat second, third, and fourth branchial cleft deformities resulted in en bloc lesion resections and reduced the chance of recurrence. Contouring the sternocleidomastoid muscle, strap muscle, and carotid sheath is key to the surgical procedure, as it leads to en bloc lesion resection while retaining the recurrent laryngeal nerve and carotid sheath. Copyright © 2014 Elsevier Ireland Ltd. All rights reserved.

Memory network plasticity after temporal lobe resection: a longitudinal functional imaging study

PubMed Central

Sidhu, Meneka K.; Stretton, Jason; Winston, Gavin P.; McEvoy, Andrew W.; Symms, Mark; Thompson, Pamela J.; Koepp, Matthias J.

2016-01-01

Abstract Anterior temporal lobe resection can control seizures in up to 80% of patients with temporal lobe epilepsy. Memory decrements are the main neurocognitive complication. Preoperative functional reorganization has been described in memory networks, but less is known of postoperative reorganization. We investigated reorganization of memory-encoding networks preoperatively and 3 and 12 months after surgery. We studied 36 patients with unilateral medial temporal lobe epilepsy (19 right) before and 3 and 12 months after anterior temporal lobe resection. Fifteen healthy control subjects were studied at three equivalent time points. All subjects had neuropsychological testing at each of the three time points. A functional magnetic resonance imaging memory-encoding paradigm of words and faces was performed with subsequent out-of-scanner recognition assessments. Changes in activations across the time points in each patient group were compared to changes in the control group in a single flexible factorial analysis. Postoperative change in memory across the time points was correlated with postoperative activations to investigate the efficiency of reorganized networks. Left temporal lobe epilepsy patients showed increased right anterior hippocampal and frontal activation at both 3 and 12 months after surgery relative to preoperatively, for word and face encoding, with a concomitant reduction in left frontal activation 12 months postoperatively. Right anterior hippocampal activation 12 months postoperatively correlated significantly with improved verbal learning in patients with left temporal lobe epilepsy from preoperatively to 12 months postoperatively. Preoperatively, there was significant left posterior hippocampal activation that was sustained 3 months postoperatively at word encoding, and increased at face encoding. For both word and face encoding this was significantly reduced from 3 to 12 months postoperatively. Patients with right temporal lobe epilepsy showed

[Myxoid liposarcoma of the anterior mediastinum. A case report and bibliography review].

PubMed

Luna-Martínez, Javier; Molina-Ramírez, Daniel; Mata-Quintero, Carlos Javier; García-Arrona, Luis Roberto; Peña-Rosas, Diana Pérez; Mondragón-Pinzón, Erwin Eduardo

2014-01-01

Five cases per year. Of those cases 50% are located in the extremities and 40% are located in the trunk and retroperitoneum. Primary mediastinal liposarcomas represent less than 1% of mediastinal tumors. A 53 year old female, native and resident of Tabasco, with a history of anterior mediastinal tumor was treated with resection at the National Institute of Cancerology about 16 years ago with histopathological diagnosis of pleomorphic liposarcoma. She started her condition with chest pain, cough and hyaline expectoration, managed as pneumonia in her unit. Other symptoms occurred, moderate exertion dyspnea and edema of lower limbs, chest computed tomography prompted for documenting mediastinal tumor measured to be 9 × 9 cm and sent to our unit which is managed with resection.

[Repeat hepatic resections].

PubMed

Popescu, I; Ciurea, S; Braşoveanu, V; Pietrăreanu, D; Tulbure, D; Georgescu, S; Stănescu, D; Herlea, V

1998-01-01

Five cases of iterative liver resections are presented, out of a total of 150 hepatectomies performed between 1.01.1995-1.01.1998. The resections were carried out for recurrent adenoma (one case), cholangiocarcinoma (two cases), hepatocellular carcinoma (one case), colo-rectal cancer metastasis (one case). Only cases with at least one major hepatic resection were included. Re-resections were more difficult than the primary resection due, first of all, to the modified vascular anatomy. Intraoperative ultrasound permitted localization of intrahepatic recurrences. Iterative liver resection appears to be the best therapeutical choice for patients with recurrent liver tumors.

Use of Valtrac™-Secured Intracolonic Bypass in Laparoscopic Rectal Cancer Resection

PubMed Central

Ye, Feng; Chen, Dong; Wang, Danyang; Lin, Jianjiang; Zheng, Shusen

2014-01-01

Abstract The occurrence of anastomotic leakage (AL) remains a major concern in the early postoperative stage. Because of the relatively high morbidity and mortality of AL in patients with laparoscopic low rectal cancer who receive an anterior resection, a fecal diverting method is usually introduced. The Valtrac™-secured intracolonic bypass (VIB) was used in open rectal resection, and played a role of protecting the anastomotic site. This study was designed to assess the efficacy and safety of the VIB in protecting laparoscopic low rectal anastomosis and to compare the efficacy and complications of VIB with those of loop ileostomy (LI). Medical records of the 43 patients with rectal cancer who underwent elective laparoscopic low anterior resection and received VIB procedure or LI between May 2011 and May 2013 were retrospectively analyzed, including the patients’ demographics, clinical features, and operative data. Twenty-four patients received a VIB and 19 patients a LI procedure. Most of the demographics and clinical features of the groups, including Dukes stages, were similar. However, the median distance of the tumor edge from the anus verge in the VIB group was significantly longer (7.5 cm; inter-quartile range [IQR] 7.0–9.5 cm) than that of the L1 group (6.0 cm; IQR 6.0–7.0 cm). None of the patients developed clinical AL. The comparisons between the LI and the VIB groups were adjusted for the significant differences in the tumor level of the groups. After adjustment, the LI group experienced longer overall postoperative hospital stay (14.0 days, IQR: 12.0, 16.0 days; P < 0.001) and incurred higher costs ($6300 (IQR: $5900, $6600)) than the VIB group (7.0 days, $4800; P < 0.05). Stoma-related complications in the ileostomy group included dermatitis (n = 2), stoma bleeding (n = 1), and wound infection after closure (n = 2). No BAR-related complications occurred. The mean time to Valtrac™ ring loosening was 14.1 ± 3

Quality of life after surgery for rectal cancer: do we still need a permanent colostomy?

PubMed

Renner, K; Rosen, H R; Novi, G; Hölbling, N; Schiessel, R

1999-09-01

A permanent colostomy is a serious limitation of the quality of life. Besides cure of cancer, preservation of sphincter function is an important goal of surgery for rectal cancer. In a prospective study a concept offering every patient with rectal cancer either sphincter salvage or a "neosphincter" was investigated, and the impact of this strategy on oncologic results, sphincter function, and quality of life was analyzed. From 1992 to 1997, 276 patients were accepted for the study. Two hundred sixty-one patients had elective surgery, and 15 patients had emergency surgery for their rectal tumors. The postoperative mortality rate was 4 percent. A radical resection (R0) was possible in 197 patients (75 percent). Anterior resection was the most common procedure (n = 87), and intersphincteric resection with coloanal anastomosis was the preferred method for low tumors (n = 65). Abdominoperineal resection was necessary in 15 cases. Thirteen patients had an immediate restoration of sphincter function by means of a dynamic graciloplasty, and 2 patients needed emergency abdominoperineal resection for bleeding. The follow-up was relatively short (median, 36.4 months) at the time of data analysis and showed a local recurrence rate of 8 percent. Although postoperative continence according to the Williams score revealed satisfactory results, subjective quality of life and the scale for specific symptoms showed a significantly worse outcome in patients with ultralow (coloanal) anastomoses compared with those with anterior resection. We conclude that for elective curative surgery of rectal cancer, a permanent colostomy is not necessary provided all presently available techniques of sphincter salvage and restoration are applied. However, the patient has to be informed about possible side effects associated with surgical procedures such as coloanal anastomosis or neosphincter reconstruction, to avoid severe psychological difficulties.

Chylous ascites occurring after low anterior resection of the rectum successfully treated with an oral fat-free elemental diet (Elental(®)).

PubMed

Nakayama, Gakuryu; Morioka, Daisuke; Murakami, Takashi; Takakura, Hideki; Miura, Yasuhiko; Togo, Shinji

2012-06-01

Chylous ascites occurring after abdominal surgery is rare. Despite being potentially critical, there is no definite treatment guideline because of its rarity. Here we present a case of massive chylous ascites occurring after rectal surgery which was successfully treated with an oral fat-free elemental diet (ED). A 67-year-old man underwent low anterior resection with para-aortic lymphadenectomy for advanced rectal cancer. Early postoperative course was uneventful and the patient was discharged from hospital 10 days after surgery; however, after discharge, abdominal distension rapidly developed. Abdominal computed tomography (CT) performed 3 weeks after surgery revealed massive ascites and laboratory findings showed remarkable hypoproteinemia and lymphopenia. Urgent diagnostic paracentesis showed the ascites to be a white milky fluid containing high levels of triglycerides (564 mg/dl), leading to a diagnosis of chyloperitoneum. Daily nutrition of the patient was entirely with a fat-free ED (30 kcal/kg/day of Elental(®), Ajinomoto Pharmaceutical Co. Ltd, Tokyo, Japan). After the initiation of oral Elental(®), abdominal distension, hypoproteinemia, and lymphopenia gradually improved. Abdominal CT performed 7 weeks after surgery showed no ascitic fluid in the abdomen, and thereafter a normal diet was initiated. Since then, no relapse of chyloperitoneum has been proven. As a result, the chylous ascites was successfully treated in the outpatient clinic.

Ultra-low magnetic damping in metallic and half-metallic systems

NASA Astrophysics Data System (ADS)

Shaw, Justin

The phenomenology of magnetic damping is of critical importance to devices which seek to exploit the electronic spin degree of freedom since damping strongly affects the energy required and speed at which a device can operate. However, theory has struggled to quantitatively predict the damping, even in common ferromagnetic materials. This presents a challenge for a broad range of applications in magnonics, spintronics and spin-orbitronics that depend on the ability to precisely control the damping of a material. I will discuss our recent work to precisely measure the intrinsic damping in several metallic and half-metallic material systems and compare experiment with several theoretical models. This investigation uncovered a metallic material composed of Co and Fe that exhibit ultra-low values of damping that approach values found in thin film YIG. Such ultra-low damping is unexpected in a metal since magnon-electron scattering dominates the damping in conductors. However, this system possesses a distinctive feature in the bandstructure that minimizes the density of states at the Fermi energy n(EF). These findings provide the theoretical framework by which such ultra-low damping can be achieved in metallic ferromagnets and may enable a new class of experiments where ultra-low damping can be combined with a charge current. Half-metallic Heusler compounds by definition have a bandgap in one of the spin channels at the Fermi energy. This feature can also lead to exceptionally low values of the damping parameter. Our results show a strong correlation of the damping with the order parameter in Co2MnGe. Finally, I will provide an overview of the recent advances in achieving low damping in thin film Heusler compounds.

Ultralow-light-level all-optical transistor in rubidium vapor

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jing, Jietai, E-mail: jtjing@phy.ecnu.edu.cn; Zhou, Zhifan; Liu, Cunjin

2014-04-14

An all-optical transistor (AOT) is a device in which one light beam can efficiently manipulate another. It is the foundational component of an all-optical communication network. An AOT that can operate at ultralow light levels is especially attractive for its potential application in the quantum information field. Here, we demonstrate an AOT driven by a weak light beam with an energy density of 2.5 × 10{sup −5} photons/(λ{sup 2}/2π) (corresponding to 6  yJ/(λ{sup 2}/2π) and about 800 total photons) using the double-Λ four-wave mixing process in hot rubidium vapor. This makes it a promising candidate for ultralow-light-level optical communication and quantum information science.

Quantitative in vivo biocompatibility of new ultralow-nickel cobalt-chromium-molybdenum alloys.

PubMed

Sonofuchi, Kazuaki; Hagiwara, Yoshihiro; Koizumi, Yuichiro; Chiba, Akihiko; Kawano, Mitsuko; Nakayama, Masafumi; Ogasawara, Kouetsu; Yabe, Yutaka; Itoi, Eiji

2016-09-01

Nickel (Ni) eluted from metallic biomaterials is widely accepted as a major cause of allergies and inflammation. To improve the safety of cobalt-chromium-molybdenum (Co-Cr-Mo) alloy implants, new ultralow-Ni Co-Cr-Mo alloys with and without zirconium (Zr) have been developed, with Ni contents of less than 0.01%. In the present study, we investigated the biocompatibility of these new alloys in vivo by subcutaneously implanting pure Ni, conventional Co-Cr-Mo, ultralow-Ni Co-Cr-Mo, and ultralow-Ni Co-Cr-Mo with Zr wires into the dorsal sides of mice. After 3 and 7 days, tissues around the wire were excised, and inflammation; the expression of IL-1β, IL-6, and TNF-α; and Ni, Co, Cr, and Mo ion release were analyzed using histological analyses, qRT-PCR, and inductively coupled plasma mass spectrometry (ICP-MS), respectively. Significantly larger amounts of Ni eluted from pure Ni wires than from the other wires, and the degree of inflammation depended on the amount of eluted Ni. Although no significant differences in inflammatory reactions were identified among new alloys and conventional Co-Cr-Mo alloys in histological and qRT-PCR analyses, ICP-MS analysis revealed that Ni ion elution from ultralow-Ni Co-Cr-Mo alloys with and without Zr was significantly lower than from conventional Co-Cr-Mo alloys. Our study, suggests that the present ultralow-Ni Co-Cr-Mo alloys with and without Zr have greater safety and utility than conventional Co-Cr-Mo alloys. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc. J Orthop Res 34:1505-1513, 2016. © 2016 Orthopaedic Research Society. Published by Wiley Periodicals, Inc.

Economic burden of cancer among patients with surgical resections of the lung, rectum, liver and uterus: results from a US hospital database claims analysis.

PubMed

Kalsekar, Iftekhar; Hsiao, Chia-Wen; Cheng, Hang; Yadalam, Sashi; Chen, Brian Po-Han; Goldstein, Laura; Yoo, Andrew

2017-12-01

To determine hospital resource utilization, associated costs and the risk of complications during hospitalization for four types of surgical resections and to estimate the incremental burden among patients with cancer compared to those without cancer. Patients (≥18 years old) were identified from the Premier Research Database of US hospitals if they had any of the following types of elective surgical resections between 1/2008 and 12/2014: lung lobectomy, lower anterior resection of the rectum (LAR), liver wedge resection, or total hysterectomy. Cancer status was determined based on ICD-9-CM diagnosis codes. Operating room time (ORT), length of stay (LOS), and total hospital costs, as well as frequency of bleeding and infections during hospitalization were evaluated. The impact of cancer status on outcomes (from a hospital perspective) was evaluated using multivariable generalized estimating equation models; analyses were conducted separately for each resection type. Among the identified patients who underwent surgical resection, 23 858 (87.9% with cancer) underwent lung lobectomy, 13 522 (63.8% with cancer) underwent LAR, 2916 (30.0% with cancer) underwent liver wedge resection and 225 075 (11.3% with cancer) underwent total hysterectomy. After adjusting for patient, procedural, and hospital characteristics, mean ORT, LOS, and hospital cost were statistically higher by 3.2%, 8.2%, and 9.2%, respectively for patients with cancer vs. no cancer who underwent lung lobectomy; statistically higher by 6.9%, 9.4%, and 9.6%, respectively for patients with cancer vs. no cancer who underwent LAR; statistically higher by 4.9%, 14.8%, and 15.7%, respectively for patients with cancer vs. no cancer who underwent liver wedge resection; and statistically higher by 16.0%, 27.4%, and 31.3%, respectively for patients with cancer vs. no cancer who underwent total hysterectomy. Among patients who underwent each type of resection, risks for bleeding and infection were generally higher

The Usefulness of Intraoperative Colonic Irrigation and Primary Anastomosis in Patients Requiring a Left Colon Resection.

PubMed

Hong, Youngki; Nam, Soomin; Kang, Jung Gu

2017-06-01

The aim of this study is to assess the short-term outcome of intraoperative colonic irrigation and primary anastomosis and to suggest the usefulness of the procedure when a preoperative mechanical bowel preparation is inappropriate. This retrospective study included 38 consecutive patients (19 male patients) who underwent intraoperative colonic irrigation and primary anastomosis for left colon disease between January 2010 and December 2016. The medical records of the patients were reviewed to evaluate the patients' characteristics, operative data, and postoperative short-term outcomes. Twenty-nine patients had colorectal cancer, 7 patients had perforated diverticulitis, and the remaining 2 patients included 1 with sigmoid volvulus and 1 with a perforated colon due to focal colonic ischemia. A diverting loop ileostomy was created in 4 patients who underwent a low anterior resection. Complications occurred in 15 patients (39.5%), and the majority was superficial surgical site infections (18.4%). Anastomotic leakage occurred in one patient (2.6%) who underwent an anterior resection due sigmoid colon cancer with obstruction. No significant difference in overall postoperative complications and superficial surgical site infections between patients with obstruction and those with peritonitis were noted. No mortality occurred during the first 30 postoperative days. The median hospital stay after surgery was 15 days (range, 8-39 days). Intraoperative colonic irrigation and primary anastomosis seem safe and feasible in selected patients. This procedure may reduce the burden of colostomy in patients requiring a left colon resection with an inappropriate preoperative mechanical bowel preparation.

Mandibular angle resection and masticatory muscle hypertrophy - a technical note and morphological optimization.

PubMed

Andreishchev, A R; Nicot, R; Ferri, J

2014-11-01

Mandibular angle resection is rarely used, but is a highly effective means of correcting facial defects. We report a mandibular angle resection technique associated with the removal of a part of hypertrophic masseter muscles and resection of buccal fat pad. Anatomical reminders: the most important entities are the facial artery and vein, crossing the lower margin of the jaw just in front of the anterior boarder of the masseter muscle and the temporomaxillary vein, passing through the temporomaxillary fossa; preoperative aspects: the preoperative examination included a radiological assessment of the shape and size of the mandibular angle; surgical technique: an intra-oral approach was usually used. The most effective and convenient method for the osteotomy was using a reciprocating saw. This technique allowed achieving a smooth contour of masseter muscles during masticatory movements or at rest. Eleven mandibular angle resections were performed from 2001 to 2009. The surgery was supplemented by remodeling the lower margin of the jaw for 5 other patients. No permanent facial palsy was noted. One patient presented a unilateral long-term loss of sensitivity of the lower lip and chin. This surgical technique if simple even requires using good technical equipment, and observing a set of rules. Using these principles allows simplifying the surgical technique, and decreasing its morbidity. A part of the masseter muscles and the buccal fat pad can sometimes be resected to improve the morphological results. Copyright © 2014 Elsevier Masson SAS. All rights reserved.

Ultra-low field nuclear magnetic resonance and magnetic resonance imaging to discriminate and identify materials

DOEpatents

Kraus, Robert H.; Matlashov, Andrei N.; Espy, Michelle A.; Volegov, Petr L.

2010-03-30

An ultra-low magnetic field NMR system can non-invasively examine containers. Database matching techniques can then identify hazardous materials within the containers. Ultra-low field NMR systems are ideal for this purpose because they do not require large powerful magnets and because they can examine materials enclosed in conductive shells such as lead shells. The NMR examination technique can be combined with ultra-low field NMR imaging, where an NMR image is obtained and analyzed to identify target volumes. Spatial sensitivity encoding can also be used to identify target volumes. After the target volumes are identified the NMR measurement technique can be used to identify their contents.

The cannabinoid anticonvulsant effect on pentylenetetrazole-induced seizure is potentiated by ultra-low dose naltrexone in mice.

PubMed

Bahremand, Arash; Shafaroodi, Hamed; Ghasemi, Mehdi; Nasrabady, Sara Ebrahimi; Gholizadeh, Shervin; Dehpour, Ahmad Reza

2008-09-01

Cannabinoid compounds are anticonvulsant since they have inhibitory effects at micromolar doses, which are mediated by activated receptors coupling to G(i/o) proteins. Surprisingly, both the analgesic and anticonvulsant effects of opioids are enhanced by ultra-low doses (nanomolar to picomolar) of the opioid antagonist naltrexone and as opioid and cannabinoid systems interact, it has been shown that ultra-low dose naltrexone also enhances cannabinoid-induced antinociception. Thus, concerning the seizure modulating properties of both classes of receptors this study investigated whether the ultra-low dose opioid antagonist naltrexone influences cannabinoid anticonvulsant effects. The clonic seizure threshold was tested in separate groups of male NMRI mice following injection of vehicle, the cannabinoid selective agonist arachidonyl-2-chloroethylamide (ACEA) and ultra-low doses of the opioid receptor antagonist naltrexone and a combination of ACEA and naltrexone doses in a model of clonic seizure induced by pentylenetetrazole (PTZ). Systemic injection of ultra-low doses of naltrexone (1pg/kg to 1ng/kg, i.p.) significantly potentiated the anticonvulsant effect of ACEA (1mg/kg, i.p.). Moreover, the very low dose of naltrexone (500pg/kg) unmasked a strong anticonvulsant effect for very low doses of ACEA (10 and 100microg/kg). A similar potentiation by naltrexone (500pg/kg) of anticonvulsant effects of non-effective dose of ACEA (1mg/kg) was also observed in the generalized tonic-clonic model of seizure. The present data indicate that the interaction between opioid and cannabinoid systems extends to ultra-low dose levels and ultra-low doses of opioid receptor antagonist in conjunction with very low doses of cannabinoids may provide a potent strategy to modulate seizure susceptibility.

The Effects of ELDRS at Ultra-Low Dose Rates

NASA Technical Reports Server (NTRS)

Chen, Dakai; Forney, James; Carts, Martin; Phan, Anthony; Cox, Stephen; Kruckmeyer, Kirby; Burns, Sam; Albarian, Rafi; Holcombe, Bruce; Little, Bradley;

Video-Assisted Laser Resection of Lung Metastases-Feasibility of a New Surgical Technique.

PubMed

Meyer, Christian; Bartsch, Detlef; Mirow, Nikolas; Kirschbaum, Andreas

2017-08-01

Background  Our pilot study describes our initial experience to do a laser resection of lung metastases under video-assisted thoracoscopic control via a minithoracotomy. With this approach, if needed, mediastinal lymphadenectomy is also possible. Methods  In this study, 15 patients (11 men and 4 women, mean age: 60 years) with resectable lung metastases of different solid primary tumors (colorectal cancer in seven patients, melanoma in three patients, renal cell carcinoma in two patients, and one each with oropharyngeal cancer, breast cancer, and seminoma) were included. An anterior minithoracotomy incision (approximately 5-7 cm length) was created in the fifth intercostal space and a soft tissue retractor (Alexis Protector; Applied Medical) was positioned. Two additional working ports were inserted. The entire lung was palpated via the minithoracotomy. All detected lung metastases were removed under thoracoscopic control. Nonanatomic resections were performed using a diode-pumped neodymium-doped yttrium aluminium garnet laser (LIMAX120; KLS Martin GmbH & Co KG) with a laser power of 80 W in a noncontact modus. Deeper parenchymal lesions were sutured. Results  A total of 29 lung metastases up to 30 mm in size were resected and all metastases diagnosed on preoperative imaging were detected. All diagnosed lung metastases were completely resected (R0). The median operation time was 102 (range: 85-120) minutes. Median blood loss was 47.6 mL and no postoperative complications occurred. Neither local recurrences nor new lung metastases were observed within 6 months after the procedures. Conclusion  Video-assisted laser resection of lung metastases is safe, effective, and fulfills the requirements of modern lung metastases surgery. Georg Thieme Verlag KG Stuttgart · New York.

Preliminary experience in laparoscopic resection of hepatic hydatidectocyst with the Da Vinci Surgical System (DVSS): a case report.

PubMed

Zou, Haibo; Luo, Lanyun; Xue, Hua; Wang, Guan; Wang, Xiankui; Luo, Le; Yao, Yutong; Xiang, Guangming; Huang, Xiaolun

2017-09-11

At present, Da Vinci robotic assisted hepatectomy has been routinely carried out in conditional units. But there is no report concerning the use of Da Vinci robots for hepatic hydatid cystectomy and experience on this aspect is seldom mentioned before. This study was to summarize the preliminary experience in laparoscopic resection of hepatic hydatidectocyst with the Da Vinci Surgical System (DVSS). A 29-year-old female diagnosed as hepatic hydatid in the right anterior lobe of liver was treated with laparoscopic resection by the DVSS under general anesthesia. Appropriate disposal of tumor cell in vascular system and disinfection of surgical field with hypertonic saline were conducted. The hepatic hydatidectocyst was resected completely with an operation time of 130 min, an intraoperative blood loss of 200 ml and a length of hospital stay for five days. The vital signs of patient were stable and no cyst fluid allergy occurred after operation. Our result showed that laparoscopic resection of hepatic hydatidectocyst by using the DVSS is safe and feasible on the basis of hospitals have rich experience in treatment of cystic echinococcosisliver, resection with DVSS and laparoscopic excision.

Optimizing Parameters of Axial Pressure-Compounded Ultra-Low Power Impulse Turbines at Preliminary Design

NASA Astrophysics Data System (ADS)

Kalabukhov, D. S.; Radko, V. M.; Grigoriev, V. A.

2018-01-01

Ultra-low power turbine drives are used as energy sources in auxiliary power systems, energy units, terrestrial, marine, air and space transport within the confines of shaft power N td = 0.01…10 kW. In this paper we propose a new approach to the development of surrogate models for evaluating the integrated efficiency of multistage ultra-low power impulse turbine with pressure stages. This method is based on the use of existing mathematical models of ultra-low power turbine stage efficiency and mass. It has been used in a method for selecting the rational parameters of two-stage axial ultra-low power turbine. The article describes the basic features of an algorithm for two-stage turbine parameters optimization and for efficiency criteria evaluating. Pledged mathematical models are intended for use at the preliminary design of turbine drive. The optimization method was tested at preliminary design of an air starter turbine. Validation was carried out by comparing the results of optimization calculations and numerical gas-dynamic simulation in the Ansys CFX package. The results indicate a sufficient accuracy of used surrogate models for axial two-stage turbine parameters selection

Reduced tar, nicotine, and carbon monoxide exposure while smoking ultralow- but not low-yield cigarettes

DOE Office of Scientific and Technical Information (OSTI.GOV)

Benowitz, N.L.; Jacob, P. III; Yu, L.

An unresolved public health issue is whether some modern cigarettes are less hazardous than other and whether patients who cannot stop smoking should be advised to switch to lower-yield cigarettes. The authors studied tar (estimated by urine mutagenicity), nicotine, and carbon monoxide exposure in habitual smokers switched from their usual brand to high- (15 mg of tar), low- (5 mg of tar), or ultralow-yield (1 mg of tar) cigarettes. There were no differences in exposure comparing high- or low-yield cigarettes, but tar and nicotine exposures were reduced by 49% and 56%, respectively, and carbon monoxide exposure by 36% while smokingmore » ultralow-yield cigarettes. Similarly, in 248 subjects smoking their self-selected brand, nicotine intake, estimated by blood concentrations of its metabolite continine, was 40% lower in those who smoked ultralow but no different in those smoking higher yields of cigarettes. The data indicate that ultralow-yield cigarettes do deliver substantial doses of tar, nicotine, and carbon monoxide, but that exposure are considerably less than for other cigarettes.« less

Pulmonary Metastasis After Resection of Cholangiocarcinoma: Incidence, Resectability, and Survival.

PubMed

Yamada, Mihoko; Ebata, Tomoki; Yokoyama, Yukihiro; Igami, Tsuyoshi; Sugawara, Gen; Mizuno, Takashi; Yamaguchi, Junpei; Nagino, Masato

2017-06-01

There are few reports on pulmonary metastasis from cholangiocarcinoma; therefore, its incidence, resectability, and survival are unclear. Patients who underwent surgical resection for cholangiocarcinoma, including intrahepatic, perihilar, and distal cholangiocarcinoma were retrospectively reviewed, and this study focused on patients with pulmonary metastasis. Between January 2003 and December 2014, 681 patients underwent surgical resection for cholangiocarcinoma. Of these, 407 patients experienced disease recurrence, including 46 (11.3%) who developed pulmonary metastasis. Of these 46 patients, 9 underwent resection for pulmonary metastasis; no resection was performed in the remaining 37 patients. R0 resection was achieved in all patients, and no complications related to pulmonary metastasectomy were observed. The median time to recurrence was significantly longer in the 9 patients who underwent surgery than in the 37 patients without surgery (2.5 vs 1.0 years, p < 0.010). Survival after surgery for primary cancer and survival after recurrence were significantly better in the former group than in the latter group (after primary cancer: 66.7 vs 0% at 5 years, p < 0.001; after recurrence: 40.0 vs 8.7% at 3 years, p = 0.003). Multivariate analysis identified the time to recurrence and resection for pulmonary metastasis as independent prognostic factors for survival after recurrence. Resection for pulmonary metastasis originating from cholangiocarcinoma can be safely performed and confers survival benefits for select patients, especially those with a longer time to recurrence after initial surgery.

Meeting design challenges of ultralow-power system-on-chip technology.

PubMed

Morris, Steve

2004-11-01

New-generation battery-powered products are required to provide increasingly greater performance. This article examines technology solutions and design techniques that can be employed to achieve ultralow-power medical devices.

Digital Protocol for Chemical Analysis at Ultralow Concentrations by Surface-Enhanced Raman Scattering.

PubMed

de Albuquerque, Carlos Diego L; Sobral-Filho, Regivaldo G; Poppi, Ronei J; Brolo, Alexandre G

2018-01-16

Single molecule surface-enhanced Raman spectroscopy (SM-SERS) has the potential to revolutionize quantitative analysis at ultralow concentrations (less than 1 nM). However, there are no established protocols to generalize the application of this technique in analytical chemistry. Here, a protocol for quantification at ultralow concentrations using SM-SERS is proposed. The approach aims to take advantage of the stochastic nature of the single-molecule regime to achieved lower limits of quantification (LOQ). Two emerging contaminants commonly found in aquatic environments, enrofloxacin (ENRO) and ciprofloxacin (CIPRO), were chosen as nonresonant molecular probes. The methodology involves a multivariate resolution curve fitting known as non-negative matrix factorization with alternating least-squares algorithm (NMF-ALS) to solve spectral overlaps. The key element of the quantification is to realize that, under SM-SERS conditions, the Raman intensity generated by a molecule adsorbed on a "hotspot" can be digitalized. Therefore, the number of SERS event counts (rather than SERS intensities) was shown to be proportional to the solution concentration. This allowed the determination of both ENRO and CIPRO with high accuracy and precision even at ultralow concentrations regime. The LOQ for both ENRO and CIPRO were achieved at 2.8 pM. The digital SERS protocol, suggested here, is a roadmap for the implementation of SM-SERS as a routine tool for quantification at ultralow concentrations.

Ultra-Low Density Organic-Inorganic Composite Materials Possessing Thermally Insulating and Acoustic Damping Properties

DTIC Science & Technology

1992-05-07

Officer. Dr. Kenneth Wynne d. Brief Description of Project- We are investigating the design and synthesis of strong, ultra-low density xerogel and aerogel ...materials of this type would have applications in a broad range of areas including lightweight engine components, high temperature coatings, aircraft wings...we plan to investigate the formation of ultra-low density composites using supercritical universal drying (SCUD) techniques. SiO2 aerogel materials

[Hepatic resections].

PubMed

Mercado, M A; Paquet, K J

1990-07-01

Liver resection are now accepted as a part of the surgical therapeutic armamentarium. In this review the anatomical and technical aspects, as well as the main indications, are discussed. The new image technique have largely contributed to the early detection of lesions that can be resected. The main indication for these procedures are malignant lesions (primary or metastatic) as well as symptomatic benign lesions. The importance to study, diagnose and treat benign lesions are justified by the possibility to detect and resect a potentially curable malignant disease. Major liver resections are contraindicated in patients with liver cirrhosis, because of a high morbimortality. Operative mortality for major liver resection is about 10% in most centers and the survival of patients with malignant disease treated by this modality is better than that of the patients treated with conservative measures. All patients with space-occupying lesions of the liver deserve the benefit of the doubt to be considered for surgical treatment. The individual features of each patient, with a judicious balance between risk and benefit, indicate or contraindicate these procedures.

The Usefulness of Intraoperative Colonic Irrigation and Primary Anastomosis in Patients Requiring a Left Colon Resection

PubMed Central

Hong, Youngki; Nam, Soomin

2017-01-01

Purpose The aim of this study is to assess the short-term outcome of intraoperative colonic irrigation and primary anastomosis and to suggest the usefulness of the procedure when a preoperative mechanical bowel preparation is inappropriate. Methods This retrospective study included 38 consecutive patients (19 male patients) who underwent intraoperative colonic irrigation and primary anastomosis for left colon disease between January 2010 and December 2016. The medical records of the patients were reviewed to evaluate the patients' characteristics, operative data, and postoperative short-term outcomes. Results Twenty-nine patients had colorectal cancer, 7 patients had perforated diverticulitis, and the remaining 2 patients included 1 with sigmoid volvulus and 1 with a perforated colon due to focal colonic ischemia. A diverting loop ileostomy was created in 4 patients who underwent a low anterior resection. Complications occurred in 15 patients (39.5%), and the majority was superficial surgical site infections (18.4%). Anastomotic leakage occurred in one patient (2.6%) who underwent an anterior resection due sigmoid colon cancer with obstruction. No significant difference in overall postoperative complications and superficial surgical site infections between patients with obstruction and those with peritonitis were noted. No mortality occurred during the first 30 postoperative days. The median hospital stay after surgery was 15 days (range, 8–39 days). Conclusion Intraoperative colonic irrigation and primary anastomosis seem safe and feasible in selected patients. This procedure may reduce the burden of colostomy in patients requiring a left colon resection with an inappropriate preoperative mechanical bowel preparation. PMID:28761871

The posterior nasoseptal flap: A novel technique for closure after endoscopic transsphenoidal resection of pituitary adenomas

PubMed Central

Barger, James; Siow, Matthew; Kader, Michael; Phillips, Katherine; Fatterpekar, Girish; Kleinberg, David; Zagzag, David; Sen, Chandranath; Golfinos, John G.; Lebowitz, Richard; Placantonakis, Dimitris G.

2018-01-01

Background: While effective for the repair of large skull base defects, the Hadad-Bassagasteguy nasoseptal flap increases operative time and can result in a several-week period of postoperative crusting during re-mucosalization of the denuded nasal septum. Endoscopic transsphenoidal surgery for pituitary adenoma resection is generally not associated with large dural defects and high-flow cerebrospinal fluid (CSF) leaks requiring extensive reconstruction. Here, we present the posterior nasoseptal flap as a novel technique for closure of skull defects following endoscopic resection of pituitary adenomas. This flap is raised in all surgeries during the transnasal exposure using septal mucoperiosteum that would otherwise be discarded during the posterior septectomy performed in binostril approaches. Methods: We present a retrospective, consecutive case series of 43 patients undergoing endoscopic transsphenoidal resection of a pituitary adenoma followed by posterior nasoseptal flap placement and closure. Main outcome measures were extent of resection and postoperative CSF leak. Results: The mean extent of resection was 97.16 ± 1.03%. Radiographic measurement showed flap length to be adequate. While a defect in the diaphragma sellae and CSF leak were identified in 21 patients during surgery, postoperative CSF leak occurred in only one patient. Conclusions: The posterior nasoseptal flap provides adequate coverage of the surgical defect and is nearly always successful in preventing postoperative CSF leak following endoscopic transsphenoidal resection of pituitary adenomas. The flap is raised from mucoperiosteum lining the posterior nasal septum, which is otherwise resected during posterior septectomy. Because the anterior septal cartilage is not denuded, raising such flaps avoids the postoperative morbidity associated with the larger Hadad-Bassagasteguy nasoseptal flap. PMID:29527390

RuO2 Thermometer for Ultra-Low Temperatures

NASA Technical Reports Server (NTRS)

Hait, Thomas; Shirron, Peter J.; DiPirro, Michael

2009-01-01

A small, high-resolution, low-power thermometer has been developed for use in ultra-low temperatures that uses multiple RuO2 chip resistors. The use of commercially available thick-film RuO2 chip resistors for measuring cryogenic temperatures is well known due to their low cost, long-term stability, and large resistance change.

Morphometrical differences between resectable and non-resectable pancreatic cancer: a fractal analysis.

PubMed

Vasilescu, Catalin; Giza, Dana Elena; Petrisor, Petre; Dobrescu, Radu; Popescu, Irinel; Herlea, Vlad

2012-01-01

Pancreatic cancer is a highly aggressive cancer with a rising incidence and poor prognosis despite active surgical treatment. Candidates for surgical resection should be carefully selected. In order to avoid unnecessary laparotomy it is useful to identify reliable factors that may predict resectability. Nuclear morphometry and fractal dimension of pancreatic nuclear features could provide important preoperative information in assessing pancreas resectability. Sixty-one patients diagnosed with pancreatic cancer were enrolled in this retrospective study between 2003 and 2005. Patients were divided into two groups: one resectable cancer group and one with non-resectable pancreatic cancer. Morphometric parameters measured were: nuclear area, length of minor axis and length of major axis. Nuclear shape and chromatin distribution of the pancreatic tumor cells were both estimated using fractal dimension. Morphometric measurements have shown significant differences between the nuclear area of the resectable group and the non-resectable group (61.9 ± 19.8µm vs. 42.2 ± 15.6µm). Fractal dimension of the nuclear outlines and chromatin distribution was found to have a higher value in the non-resectable group (p<0.05). Objective measurements should be performed to improve risk assessment and therapeutic decisions in pancreatic cancer. Nuclear morphometry of the pancreatic nuclear features can provide important pre-operative information in resectability assessment. The fractal dimension of the nuclear shape and chromatin distribution may be considered a new promising adjunctive tool for conventional pathological analysis.

Surgical resection of sinonasal hemangiopericytoma involving anterior skull base: Case reports and literature review.

PubMed

Simmonds, Jonathan C; Rebeiz, Elie E

Hemangiopericytomas are soft tissue tumors composed of pericytic cells that are characterized by their "staghorn" vascular branching and their variable clinical presentation. Fifteen to 25% of all HPC occur in the head and neck, with only 5% found in the nose or paranasal sinuses. Sinonasal hemangiopericytoma (SNHPC) is considered distinct from its soft tissue counterpart - the former showing a more uniform cellular organization, has convincing pericytic differentiation and is associated with a far better prognosis. With less than 200 cases of SNHPC reported in the literature, only limited assumptions can be made about this rare tumor. The purpose of this article is to add to the growing body of literature on this disease. We report two new cases of SNHCP - both in female patients who presented with epistaxis and anosmia. Pulsatile vascular masses were visualized with nasal endoscopy - one in the left middle meatus and the second one near the cribriform plate. CT and MRI studies show enhancing masses in the left nasal cavities with thinning and erosion of the skull base. Diagnoses were confirmed by pathology which reported spindle cell neoplasm staining positively for VEGF, NSE, factor XIIIa, S-100 protein, and CD34, and negative for actin, desmin, CD31, and pankeratin, consistent with hemangiopericytoma. In one patient, embolization of the sphenopalatine and labial artery as well as pre-operative radiation therapy was performed before complete endoscopic resection was undertaken. The second patient had a tumor invading the skull base, so a craniofacial resection was performed. Both patients remained free of disease two years after surgery. Review of the literature and treatment options are discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

Anatomic liver resection of right paramedian sector: ventral and dorsal resection.

PubMed

Fujimoto, Jiro; Hai, Seikan; Hirano, Tadamichi; Iimuro, Yuji; Yamanaka, Junichi

2015-07-01

The purpose of anatomic resection of the liver is to systemically eliminate malignant tumors that spread via the portal vein. Moreover, it results in reducing bleeding and bile leakage from the cut surface of the liver because Glisson's pedicle resection leads to parenchyma transection. Anatomical resection includes hemi-hepatectomy, sectionectomy, and segmentectomy. Recently, it has been noticed that this concept is not always appropriate for the liver resection including the right paramedian sector. It can be divided vertically into the ventral and the dorsal area according to the ramification of the third order of the portal veins. In the present study, we focused on the right paramedian sector and described techniques of surgical procedures of hepatectomy including resection of the ventral or dorsal areas. © 2015 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Meta-analysis of elective surgical complications related to defunctioning loop ileostomy compared with loop colostomy after low anterior resection for rectal carcinoma.

PubMed

Geng, Hong Zhi; Nasier, Dilidan; Liu, Bing; Gao, Hua; Xu, Yi Ke

2015-10-01

Introduction Defunctioning loop ileostomy (LI) and loop colostomy (LC) are used widely to protect/treat anastomotic leakage after colorectal surgery. However, it is not known which surgical approach has a lower prevalence of surgical complications after low anterior resection for rectal carcinoma (LARRC). Methods We conducted a literature search of PubMed, MEDLINE, Ovid, Embase and Cochrane databases to identify studies published between 1966 and 2013 focusing on elective surgical complications related to defunctioning LI and LC undertaken to protect a distal rectal anastomosis after LARRC. Results Five studies (two randomized controlled trials, one prospective non-randomized trial, and two retrospective trials) satisfied the inclusion criteria. Outcomes of 1,025 patients (652 LI and 373 LC) were analyzed. After the construction of a LI or LC, there was a significantly lower prevalence of sepsis (p=0.04), prolapse (p=0.03), and parastomal hernia (p=0.02) in LI patients than in LC patients. Also, the prevalence of overall complications was significantly lower in those who received LIs compared with those who received LCs (p<0.0001). After closure of defunctioning loops, there were significantly fewer wound infections (p=0.006) and incisional hernias (p=0.007) in LI patients than in LC patients, but there was no significant difference between the two groups in terms of overall complications. Conclusions The results of this meta-analysis show that a defunctioning LI may be superior to LC with respect to a lower prevalence of surgical complications after LARRC.

Decomposition of carbon dioxide by recombining hydrogen plasma with ultralow electron temperature

NASA Astrophysics Data System (ADS)

Yamazaki, Masahiro; Nishiyama, Shusuke; Sasaki, Koichi

2018-06-01

We examined the rate coefficient for the decomposition of CO2 in low-pressure recombining hydrogen plasmas with electron temperatures between 0.15 and 0.45 eV, where the electron-impact dissociation was negligible. By using this ultralow-temperature plasma, we clearly observed decomposition processes via vibrational excited states. The rate coefficient of the overall reaction, CO2 + e → products, was 1.5 × 10‑17 m3/s in the ultralow-temperature plasma, which was 10 times larger than the decomposition rate coefficient of 2 × 10‑18 m3/s in an ionizing plasma with an electron temperature of 4 eV.

[Radical resective surgery for the management of rectosigmoidal endometriosis. Clinical case].

PubMed

Bannura, G; Valencia, C; Corredoira, Y

1998-11-01

We report a 35 years old female with a profound rectosigmoidal endometriosis, who had been subjected to multiple laparoscopic procedures and open surgery due to infertility in the last five years. Main presenting symptoms were cyclic hematochezia during the menstrual periods associated to pelvic pain. Colonoscopy was inconclusive, barium enema showed a marked stenosis of the zone, appearing as an extrinsic compression. CAT scan showed a homogeneous, solid parauterine mass. During surgery, an inflammatory mass with multiple endometriotic foci was found. A low anterior resection with mechanical anastomosis was done, preserving the uterus and left adnexa. Two months later, the patient became pregnant and an elective cesarean section was done at 38 weeks of gestation, giving birth to a healthy newborn. Radical resective surgery for rectosigmoidal endometriosis is indicated in patients with intense and recurrent symptoms in whom hormonal treatment has failed and when a tumor cannot be discarded. The fertility rate, when adnexa and uterus are preserved, is 40% and symptomatic improvement is achieved in 85% of patients.

Anteriorly placed tumors to the conus: removal by interradicular window.

PubMed

Ciappetta, P; Taurone, S; Spoletini, M; Artico, M

2017-01-01

Tumors anteriorly situated to the medullary conus are rarely encountered and represent a true surgical challenge. We examined the literature on this topic, concluding that there are no previous reports on alternative surgical techniques different to the traditional one. We report two cases of intradural extramedullary tumor operated on by a technique performed through a window opened between the spinal roots, which allows an easy, effective and useful resection. We describe a new operative technique which ensures a complete removal of these tumors and discuss clinical implications in the light of the available literature on this topic.

Emphysema quantification and lung volumetry in chest X-ray equivalent ultralow dose CT - Intra-individual comparison with standard dose CT.

PubMed

Messerli, Michael; Ottilinger, Thorsten; Warschkow, René; Leschka, Sebastian; Alkadhi, Hatem; Wildermuth, Simon; Bauer, Ralf W

2017-06-01

To determine whether ultralow dose chest CT with tin filtration can be used for emphysema quantification and lung volumetry and to assess differences in emphysema measurements and lung volume between standard dose and ultralow dose CT scans using advanced modeled iterative reconstruction (ADMIRE). 84 consecutive patients from a prospective, IRB-approved single-center study were included and underwent clinically indicated standard dose chest CT (1.7±0.6mSv) and additional single-energy ultralow dose CT (0.14±0.01mSv) at 100kV and fixed tube current at 70mAs with tin filtration in the same session. Forty of the 84 patients (48%) had no emphysema, 44 (52%) had emphysema. One radiologist performed fully automated software-based pulmonary emphysema quantification and lung volumetry of standard and ultralow dose CT with different levels of ADMIRE. Friedman test and Wilcoxon rank sum test were used for multiple comparison of emphysema and lung volume. Lung volumes were compared using the concordance correlation coefficient. The median low-attenuation areas (LAA) using filtered back projection (FBP) in standard dose was 4.4% and decreased to 2.6%, 2.1% and 1.8% using ADMIRE 3, 4, and 5, respectively. The median values of LAA in ultralow dose CT were 5.7%, 4.1% and 2.4% for ADMIRE 3, 4, and 5, respectively. There was no statistically significant difference between LAA in standard dose CT using FBP and ultralow dose using ADMIRE 4 (p=0.358) as well as in standard dose CT using ADMIRE 3 and ultralow dose using ADMIRE 5 (p=0.966). In comparison with standard dose FBP the concordance correlation coefficients of lung volumetry were 1.000, 0.999, and 0.999 for ADMIRE 3, 4, and 5 in standard dose, and 0.972 for ADMIRE 3, 4 and 5 in ultralow dose CT. Ultralow dose CT at chest X-ray equivalent dose levels allows for lung volumetry as well as detection and quantification of emphysema. However, longitudinal emphysema analyses should be performed with the same scan protocol and

Resection followed by stereotactic radiosurgery to resection cavity for intracranial metastases.

PubMed

Do, Ly; Pezner, Richard; Radany, Eric; Liu, An; Staud, Cecil; Badie, Benham

2009-02-01

In patients who undergo resection of central nervous system metastases, whole brain radiotherapy (WBRT) is added to reduce the rates of recurrence and neurologic death. However, the risk of late neurotoxicity has led many patients to decline WBRT. We offered adjuvant stereotactic radiosurgery (SRS) or stereotactic radiotherapy (SRT) as an alternative to select patients with resected brain metastases. We performed a retrospective review of patients who underwent brain metastasis resection followed by SRS/SRT. WBRT was administered only as salvage treatment. Patients had one to four brain metastases. The dose was 15-18 Gy for SRS and 22-27.5 Gy in four to six fractions for SRT. Target margins were typically expanded by 1 mm for rigid immobilization and 3 mm for mask immobilization. SRS/SRT involved the use of linear accelerator radiosurgery using the IMRT 21EX or Helical Tomotherapy unit. Between December 1999 and January 2007, 30 patients diagnosed with intracranial metastases were treated with resection followed by SRS or SRT to the resection cavity. Of the 30 patients, 4 (13.3%) developed recurrence in the resection cavity, and 19 (63%) developed recurrences in new intracranial sites. The actuarial 12-month survival rate was 82% for local recurrence-free survival, 31% for freedom from new brain metastases, 67% for neurologic deficit-free survival, and 51% for overall survival. Salvage WBRT was performed in 14 (47%) of the 30 patients. Our results suggest that for patients with newly diagnosed brain metastases treated with surgical resection, postoperative SRS/SRT to the resection cavity is a feasible option. WBRT can be reserved as salvage treatment with acceptable neurologic deficit-free survival.

[Endoscopic full-thickness resection].

PubMed

Meier, B; Schmidt, A; Caca, K

2016-08-01

Conventional endoscopic resection techniques such as endoscopic mucosal resection (EMR) or endoscopic submucosal dissection (ESD) are powerful tools for the treatment of gastrointestinal (GI) neoplasms. However, those techniques are limited to the superficial layers of the GI wall (mucosa and submucosa). Lesions without lifting sign (usually arising from deeper layers) or lesions in difficult anatomic positions (appendix, diverticulum) are difficult - if not impossible - to resect using conventional techniques, due to the increased risk of complications. For larger lesions (>2 cm), ESD appears to be superior to the conventional techniques because of the en bloc resection, but the procedure is technically challenging, time consuming, and associated with complications even in experienced hands. Since the development of the over-the-scope clips (OTSC), complications like bleeding or perforation can be endoscopically better managed. In recent years, different endoscopic full-thickness resection techniques came to the focus of interventional endoscopy. Since September 2014, the full-thickness resection device (FTRD) has the CE marking in Europe for full-thickness resection in the lower GI tract. Technically the device is based on the OTSC system and combines OTSC application and snare polypectomy in one step. This study shows all full-thickness resection techniques currently available, but clearly focuses on the experience with the FTRD in the lower GI tract.

Electroplating method for producing ultralow-mass fissionable deposits

DOEpatents

Ruddy, Francis H.

1989-01-01

A method for producing ultralow-mass fissionable deposits for nuclear reactor dosimetry is described, including the steps of holding a radioactive parent until the radioactive parent reaches secular equilibrium with a daughter isotope, chemically separating the daughter from the parent, electroplating the daughter on a suitable substrate, and holding the electroplated daughter until the daughter decays to the fissionable deposit.

Aminosilanization nanoadhesive layer for nanoelectric circuits with porous ultralow dielectric film.

PubMed

Zhao, Zhongkai; He, Yongyong; Yang, Haifang; Qu, Xinping; Lu, Xinchun; Luo, Jianbin

2013-07-10

An ultrathin layer is investigated for its potential application of replacing conventional diffusion barriers and promoting interface adhesion for nanoelectric circuits with porous ultralow dielectrics. The porous ultralow dielectric (k ≈ 2.5) substrate is silanized by 3-aminopropyltrimethoxysilane (APTMS) to form the nanoadhesive layer by performing oxygen plasma modification and tailoring the silanization conditions appropriately. The high primary amine content is obtained in favor of strong interaction between amino groups and copper. And the results of leakage current measurements of metal-oxide-semiconductor capacitor structure demonstrate that the aminosilanization nanoadhesive layer can block copper diffusion effectively and guarantee the performance of devices. Furthermore, the results of four-point bending tests indicate that the nanoadhesive layer with monolayer structure can provide the satisfactory interface toughness up to 6.7 ± 0.5 J/m(2) for Cu/ultralow-k interface. Additionally, an annealing-enhanced interface toughness effect occurs because of the formation of Cu-N bonding and siloxane bridges below 500 °C. However, the interface is weakened on account of the oxidization of amines and copper as well as the breaking of Cu-N bonding above 500 °C. It is also found that APTMS nanoadhesive layer with multilayer structure provides relatively low interface toughness compared with monolayer structure, which is mainly correlated to the breaking of interlayer hydrogen bonding.

[A Case Report on a Successful Resection after FOLFIRI plus Cetuximab Therapy for Unresectable Colorectal Cancer with Multiple Liver Metastases].

PubMed

Kanamori, Min; Kurumiya, Yasuhiro; Mizuno, Keisuke; Sekoguchi, Ei; Kobayashi, Satoshi; Fukami, Yasuyuki; Kiriyama, Muneyasu; Aoyama, Hiroki; Oiwa, Takashi; Miyamura, Kei; Jinno, Takanori; Nakashima, Yu; Mori, Makiko

2017-05-01

The patient was a 66-year-old woman with a history of right breast cancer 20 years prior. Her chief complaint was hematochezia, and she was diagnosed as having rectal cancer. She underwent laparoscopic high anterior resection. We made a diagnosis of moderately differentiated adenocarcinoma, type 2, 25×20 mm, pMP, pN0, Stage I, KRAS being wild-type. Multiple liver metastases were detected 6 months after the surgery. Tumor contacted with grison. The tumor was not completely resected as evidenced by the small liver remnant volume. Conversion therapy was administered, and the patient received 6 courses of FOLFIRI plus cetuximab therapy. Alopecia and grade 1 eruption were observed as adverse effects of the chemotherapy. The tumor size was reduced, and we resected the tumor by performing right lobectomy and partial hepatectomy. At 1 year 3 months after surgery, no recurrence was observed.

Complex posterior thoracic wall reconstruction using a crossover combined latissimus dorsi and serratus anterior free flap.

PubMed

Bodin, Frédéric; Dissaux, Caroline; Steib, Jean-Paul; Massard, Gilbert

2016-03-01

Radical resection of an extended malignant sarcoma of the chest wall requires full-thickness thoracic chest wall reconstruction. Reconstruction is tedious in the case of posteriorly located tumours, because the ipsilateral pedicled myocutaneous latissimus dorsi flap is involved and hence not usable for soft tissue coverage. We report an original case of a left giant dorsal chondrosarcoma originating from the 11th costovertebral joint. After extended resection and skeletal reconstruction, soft tissue coverage was achieved with an original contralateral free flap encompassing both latissimus dorsi and serratus anterior muscles. The flap pedicle was anastomosed to the ipsilateral thoracodorsal vessels. © The Author 2015. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

Ultra-low Temperature Curable Conductive Silver Adhesive with different Resin Matrix

NASA Astrophysics Data System (ADS)

Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Li, Xing; Qin, Lei

2018-03-01

The ultra-low temperature curable conductive silver adhesive with curing temperature less than 100 °C needed urgently for the surface conductive treatment of piezoelectric composite material due to the low thermal resistance of composite material and low adhesion strength of adhesive. An ultra-low temperature curable conductive adhesive with high adhesion strength was obtained for the applications of piezoelectric composite material. The microstructure, conductive properties and adhesive properties with different resin matrix were investigated. The conductive adhesive with AG-80 as the resin matrix has the shorter curing time (20min), lower curing temperature (90°C) and higher adhesion strength (7.6MPa). The resistivity of AG-80 sample has the lower value (2.13 × 10-4Ω·cm) than the 618 sample (4.44 × 10-4Ω·cm).

A "reverse direction" technique of single-port left upper pulmonary resection.

PubMed

Zhang, Min; Sihoe, Alan D L; Du, Ming

2016-08-01

Single-port video-assisted thoracoscopic surgery (VATS) left upper lobectomy is difficult amongst all the lobes. At the beginning of single-port lobectomies, the upper lobes were believed not to be amenable for single-port approach due to the difficult angulation for staplers. Gonzalez reported the first single-port VATS left upper lobectomy in 2011. We report a new technique of single-port VATS left upper lobectomy with the concept of "reverse direction". We divide the apical-anterior arterial trunk with upper vein in the last. The procedure sequence is described as follows: posterior artery, lingular artery, bronchus and finally upper vein & apical-anterior arterial trunk. This method could overcome the angular limitations frequently encountered in single-port VATS procedures; reduce the risk of injuries to pulmonary artery; broaden the indications of single-port the upper lobe of the left lung (LUL) to include hypoplastic lung fissures. Limitations of this new practice include the enlargement or severe calcifications of hilar and bronchial lymph nodes. A "reverse direction" technique of single-port left upper pulmonary resection is feasible and safe.

Orbitopterional Approach for the Resection of a Suprasellar Craniopharyngioma: Adapting the Strategy to the Microsurgical and Pathologic Anatomy.

PubMed

Nguyen, Vincent; Basma, Jaafar; Klimo, Paul; Sorenson, Jeffrey; Michael, L Madison

2018-04-01

Objectives  To describe the orbitopterional approach for the resection of a suprasellar craniopharyngioma with emphasis on the microsurgical and pathological anatomy of such lesions. Design  After completing the orbitopterional craniotomy in one piece including a supraorbital ridge osteotomy, the Sylvian fissure was split in a distal to proximal direction. The ipsilateral optic nerve and internal carotid artery were identified. Establishing a corridor to the tumor through both the opticocarotid and optic cisterns allowed for a wide angle of attack. Using both corridors, a microsurgical gross total resection was achieved. A radical resection required transection of the stalk at the level of the hypothalamus. Photographs of the region are borrowed from Dr Rhoton's laboratory to illustrate the microsurgical anatomy. Understanding the cisternal and topographic relationships of the optic nerve, optic chiasm, and internal carotid artery is critical to achieving gross total resection while preserving normal anatomy. Participants  The surgery was performed by the senior author assisted by Dr. Jaafar Basma. The video was edited by Dr. Vincent Nguyen. Outcome Measures  Outcome was assessed with extent of resection and postoperative visual function. Results  A gross total resection of the tumor was achieved. The patient had resolution of her bitemporal hemianopsia. She had diabetes insipidus with normal anterior pituitary function. Conclusions  Understanding the microsurgical anatomy of the suprasellar region and the pathological anatomy of craniopharyngiomas is necessary to achieve a good resection of these tumors. The orbitopterional approach provides the appropriate access for such endeavor. The link to the video can be found at: https://youtu.be/Be6dtYIGqfs .

Lowering the recurrence rate in pigmented villonodular synovitis: A series of 120 resections.

PubMed

Capellen, Carl Ferdinand; Tiling, Reinhold; Klein, Alexander; Baur-Melnyk, Andrea; Knösel, Thomas; Birkenmaier, Christof; Roeder, Falk; Jansson, Volkmar; Dürr, Hans Roland

2018-05-16

Tenosynovial giant-cell tumour or pigmented villonodular synovitis is an aggressive synovial proliferative disease, with the knee joint being the most commonly affected joint. The mainstay of therapy is surgical resection. The aim of this study was to evaluate the main patient characteristics, treatment and outcomes in a large single-centre retrospective study, focusing on meticulous aggressive open surgical procedures. From 1996 through 2014, 122 surgical interventions were performed in 105 patients. All patients underwent open synovectomy and when the knee joint was affected, combined anterior and posterior synovectomy. Radiotherapy was applied in 2 patients, radiosynoviorthesis in 27 patients. In histopathology, the diffuse type was seen in 66 (54%) lesions. Two patients were lost during follow-up. At a median follow-up time of 71 months (range: 13-238), 22 (18%) lesions recurred within a median of 18 months, >90% in the first 3 years. Out of those 22 recurrences, 9 (11%) were seen in primary disease and 13 (34%) were a second recurrence. After renewed resection, 6 (5%) out of the 120 resections had persistent tumour at the end of follow-up. Based on the number of patients with complete follow-up (n = 103), this represents 5.8%. In diffuse-type pigmented villonodular synovitis, total synovectomy might be difficult to achieve. As shown in our results and also in the literature, meticulous open resection, especially in difficult to approach areas such as the popliteal space, reduces local recurrence rates. External beam radiation is an option in prevention of otherwise non-operable local recurrences or in non-operable disease.

Meta-analysis of elective surgical complications related to defunctioning loop ileostomy compared with loop colostomy after low anterior resection for rectal carcinoma

PubMed Central

Geng, Hong Zhi; Nasier, Dilidan; Liu, Bing; Gao, Hua; Xu, Yi Ke

2015-01-01

Introduction Defunctioning loop ileostomy (LI) and loop colostomy (LC) are used widely to protect/treat anastomotic leakage after colorectal surgery. However, it is not known which surgical approach has a lower prevalence of surgical complications after low anterior resection for rectal carcinoma (LARRC). Methods We conducted a literature search of PubMed, MEDLINE, Ovid, Embase and Cochrane databases to identify studies published between 1966 and 2013 focusing on elective surgical complications related to defunctioning LI and LC undertaken to protect a distal rectal anastomosis after LARRC. Results Five studies (two randomized controlled trials, one prospective non-randomized trial, and two retrospective trials) satisfied the inclusion criteria. Outcomes of 1,025 patients (652 LI and 373 LC) were analyzed. After the construction of a LI or LC, there was a significantly lower prevalence of sepsis (p=0.04), prolapse (p=0.03), and parastomal hernia (p=0.02) in LI patients than in LC patients. Also, the prevalence of overall complications was significantly lower in those who received LIs compared with those who received LCs (p<0.0001). After closure of defunctioning loops, there were significantly fewer wound infections (p=0.006) and incisional hernias (p=0.007) in LI patients than in LC patients, but there was no significant difference between the two groups in terms of overall complications. Conclusions The results of this meta-analysis show that a defunctioning LI may be superior to LC with respect to a lower prevalence of surgical complications after LARRC. PMID:26274752

Structured pathology reporting improves the macroscopic assessment of rectal tumour resection specimens.

PubMed

King, Simon; Dimech, Margaret; Johnstone, Susan

2016-06-01

We examined whether introduction of a structured macroscopic reporting template for rectal tumour resection specimens improved the completeness and efficiency in collecting key macroscopic data elements. Fifty free text (narrative) macroscopic reports retrieved from 2012 to 2014 were compared with 50 structured macroscopic reports from 2013 to 2015, all of which were generated at John Hunter Hospital, Newcastle, NSW. The six standard macroscopic data elements examined in this study were reported in all 50 anatomical pathology reports using a structured macroscopic reporting dictation template. Free text reports demonstrated significantly impaired data collection when recording intactness of mesorectum (p<0.001), relationship to anterior peritoneal reflection (p=0.028) and distance of tumour to the non-peritonealised circumferential margin (p<0.001). The number of words used was also significantly (p<0.001) reduced using pre-formatted structured reports compared to free text reports. The introduction of a structured reporting dictation template improves data collection and may reduce the subsequent administrative burden when macroscopically evaluating rectal resections. Copyright © 2016 Royal College of Pathologists of Australasia. Published by Elsevier B.V. All rights reserved.

Ultra-Low Noise Germanium Neutrino Detection system (ULGeN).

DOE Office of Scientific and Technical Information (OSTI.GOV)

Cabrera-Palmer, Belkis; Barton, Paul

Monitoring nuclear power plant operation by measuring the antineutrino flux has become an active research field for safeguards and non-proliferation. We describe various efforts to demonstrate the feasibility of reactor monitoring based on the detection of the Coherent Neutrino Nucleus Scattering (CNNS) process with High Purity Germanium (HPGe) technology. CNNS detection for reactor antineutrino energies requires lowering the electronic noise in low-capacitance kg-scale HPGe detectors below 100 eV as well as stringent reduction in other particle backgrounds. Existing state- of-the-art detectors are limited to an electronic noise of 95 eV-FWHM. In this work, we employed an ultra-low capacitance point-contact detectormore » with a commercial integrated circuit preamplifier- on-a-chip in an ultra-low vibration mechanically cooled cryostat to achieve an electronic noise of 39 eV-FWHM at 43 K. We also present the results of a background measurement campaign at the Spallation Neutron Source to select the area with sufficient low background to allow a successful first-time measurement of the CNNS process.« less

An ultra-low power output capacitor-less low-dropout regulator with slew-rate-enhanced circuit

NASA Astrophysics Data System (ADS)

Cheng, Xin; Zhang, Yu; Xie, Guangjun; Yang, Yizhong; Zhang, Zhang

2018-03-01

An ultra-low power output-capacitorless low-dropout (LDO) regulator with a slew-rate-enhanced (SRE) circuit is introduced. The increased slew rate is achieved by sensing the transient output voltage of the LDO and then charging (or discharging) the gate capacitor quickly. In addition, a buffer with ultra-low output impedance is presented to improve line and load regulations. This design is fabricated by SMIC 0.18 μm CMOS technology. Experimental results show that, the proposed LDO regulator only consumes an ultra-low quiescent current of 1.2 μA. The output current range is from 10 μA to 200 mA and the corresponding variation of output voltage is less than 40 mV. Moreover, the measured line regulation and load regulation are 15.38 mV/V and 0.4 mV/mA respectively. Project supported by the National Natural Science Foundation of China (Nos. 61401137, 61404043, 61674049).

The evolution of analgesia in an 'accelerated' recovery programme for resectional laparoscopic colorectal surgery with anastomosis.

PubMed

Zafar, N; Davies, R; Greenslade, G L; Dixon, A R

2010-02-01

The study set out to analyse the outcomes of an evolving accelerated recovery programme after laparoscopic colorectal resection (LCR). The results of a prospective electronic database (March 2000 - April 2008) were analysed. There were 353 consecutive patients undergoing 'three port' high anterior resection (AR) (237 without covering stoma) and 166 a right hemicolectomy (RHC). One hundred thirty-eight had postoperative analgesia using paracetamol IV and oral analgesia (IVP); 27 (16.3%) received additional parenteral morphine and were excluded. Patient controlled morphine analgesia (PCA) was used in 138. Transversus abdominis plane (TAP) blocks, supplemented by IV paracetamol and oral analgesia were used in the last 50 patients. The time to the resumption of diet was significantly reduced with TAP analgesia (median 12 h) and IVP (median 12 h) compared with PCA median (36 h) (chi(2) = 143; 4df: P < 0.001). The postoperative hospital stay was significantly reduced with TAP analgesia (median 2 days) and IVP (median 3 days) compared with PCA (median 5 days); chi(2) = 73; 2df: P < 0.001. Seventeen (34%) TAP and nine (6.5%) IVP patients were discharged within 24 h of surgery compared with no patient in the PCA group. Ninety-three per cent of PCA, 35% IVP and 10% TAP patients were discharged in more than 3 days. The movement towards 'accelerated recovery' was not associated with any increased risk of urinary retention, return to theatre, readmission and/or 30 day mortality. Laparoscopic surgery utilizing IV paracetamol and TAP blocks for postoperative analgesia aids safe effective 'accelerated recovery' in an unselected patient population undergoing right hemicolectomy and high anterior resection. Routine epidural anaesthesia is unnecessary for LCR. Morphine PCA is associated with delayed recovery.

X-band ultralow-noise maser amplifier performance

NASA Technical Reports Server (NTRS)

Glass, G. W.; Ortiz, G. G.; Johnson, D. L.

1994-01-01

Noise temperature measurements of an 8440-MHz ultralow noise maser amplifier (ULNA) have been performed at subatmospheric, liquid-helium temperatures. The traveling-wave maser was operated while immersed in a liquid helium bath. The lowest input noise temperature measured was 1.43 +/- 0.16 K at a physical temperature of 1.60 K. At this physical temperature, the observed gain per centimeter of ruby was 4.9 dB/cm. The amplifier had a 3-dB bandwidth of 76 MHz.

Economic method for measuring ultra-low flow rates of fluids

NASA Technical Reports Server (NTRS)

Bogdanovic, J. A.; Keller, W. F.

1970-01-01

Capillary tube flowmeter measures ultra-low flows of very corrosive fluids /such as chlorine trifluoride and liquid fluorine/ and other liquids with reasonable accuracy. Flowmeter utilizes differential pressure transducer and operates on the principle that for laminar flow in the tube, pressure drop is proportional to flow rate.

Augmented reality in bone tumour resection

PubMed Central

Park, Y. K.; Gupta, S.; Yoon, C.; Han, I.; Kim, H-S.; Choi, H.; Hong, J.

2017-01-01

Objectives We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model. Methods We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice. Results The mean error of 164 resections in 82 femurs in the AR group was 1.71 mm (0 to 6). The mean error of 82 resections in 41 femurs in the conventional resection group was 2.64 mm (0 to 11) (p < 0.05, one-way analysis of variance). The probabilities of a surgeon obtaining a 10 mm surgical margin with a 3 mm tolerance were 90.2% in AR-assisted resections, and 70.7% in conventional resections. Conclusion We demonstrated that the accuracy of tumour resection was satisfactory with the help of the AR navigation system, with the tumour shown as a virtual template. In addition, this concept made the navigation system simple and available without additional cost or time. Cite this article: H. S. Cho, Y. K. Park, S. Gupta, C. Yoon, I. Han, H-S. Kim, H. Choi, J. Hong. Augmented reality in bone tumour resection: An experimental study. Bone Joint Res 2017;6:137–143. PMID:28258117

Combined robotic transanal total mesorectal excision (R-taTME) and single-site plus one-port (R-SSPO) technique for ultra-low rectal surgery-initial experience with a new operation approach.

PubMed

Kuo, Li-Jen; Ngu, James Chi-Yong; Tong, Yiu-Shun; Chen, Chia-Che

2017-02-01

Robot-assisted rectal surgery is gaining popularity, and robotic single-site surgery is also being explored clinically. We report our initial experience with robotic transanal total mesorectal excision (R-taTME) and radical proctectomy using the robotic single-site plus one-port (R-SSPO) technique for low rectal surgery. Between July 2015 and March 2016, 15 consecutive patients with ultra-low rectal lesions underwent R-taTME followed by radical proctectomy using the R-SSPO technique by a single surgeon. The clinical and pathological results were retrospectively analyzed. The median operative time was 473 (range, 335-569) min, and the estimated blood loss was 33 (range, 30-50) mL. The median number of lymph nodes harvested was 12 (range, 8-18). The median distal resection margin was 1.4 (range, 0.4-3.5) cm, and all patients had clear circumferential resection margins. We encountered a left ureteric transection intraoperatively in one patient, and another patient required reoperation for postoperative adhesive intestinal obstruction. There was no 30-day mortality. R-taTME followed by radical proctectomy using the R-SSPO technique for patients with low rectal lesions is technically feasible and safe without compromising oncologic outcomes. However, there were considerable limitations and a steep learning curve using current robotic technology.

Anatomy of Hepatic Resectional Surgery.

PubMed

Lowe, Michael C; D'Angelica, Michael I

2016-04-01

Liver anatomy can be variable, and understanding of anatomic variations is crucial to performing hepatic resections, particularly parenchymal-sparing resections. Anatomic knowledge is a critical prerequisite for effective hepatic resection with minimal blood loss, parenchymal preservation, and optimal oncologic outcome. Each anatomic resection has pitfalls, about which the operating surgeon should be aware and comfortable managing intraoperatively. Copyright © 2016 Elsevier Inc. All rights reserved.

Posterior-only approach for lumbar vertebral column resection and expandable cage reconstruction for spinal metastases.

PubMed

Jandial, Rahul; Kelly, Brandon; Chen, Mike Yue

2013-07-01

The increasing incidence of spinal metastasis, a result of improved systemic therapies for cancer, has spurred a search for an alternative method for the surgical treatment of lumbar metastases. The authors report a single-stage posterior-only approach for resecting any pathological lumbar vertebral segment and reconstructing with a medium to large expandable cage while preserving all neurological structures. The authors conducted a retrospective consecutive case review of 11 patients (5 women, 6 men) with spinal metastases treated at 1 institution with single-stage posterior-only vertebral column resection and reconstruction with an expandable cage and pedicle screw fixation. For all patients, the indications for operative intervention were spinal cord compression, cauda equina compression, and/or spinal instability. Neurological status was classified according to the American Spinal Injury Association impairment scale, and functional outcomes were analyzed by using a visual analog scale for pain. For all patients, a circumferential vertebral column resection was achieved, and full decompression was performed with a posterior-only approach. Each cage was augmented by posterior pedicle screw fixation extending 2 levels above and below the resected level. No patient required a separate anterior procedure. Average estimated blood loss and duration of each surgery were 1618 ml (range 900-4000 ml) and 6.6 hours (range 4.5-9 hours), respectively. The mean follow-up time was 14 months (range 10-24 months). The median survival time after surgery was 17.7 months. Delayed hardware failure occurred for 1 patient. Preoperatively, 2 patients had intractable pain with intact lower-extremity strength and 8 patients had severe intractable pain, lower-extremity paresis, and were unable to walk; 4 of whom regained the ability to walk after surgery. Two patients who were paraplegic before decompression recovered substantial function but remained wheelchair bound, and 2 patients

Number of Ribs Resected is Associated with Respiratory Complications Following Lobectomy with en bloc Chest Wall Resection.

PubMed

Geissen, Nicole M; Medairos, Robert; Davila, Edgar; Basu, Sanjib; Warren, William H; Chmielewski, Gary W; Liptay, Michael J; Arndt, Andrew T; Seder, Christopher W

2016-08-01

Pulmonary lobectomy with en bloc chest wall resection is a common strategy for treating lung cancers invading the chest wall. We hypothesized a direct relationship exists between number of ribs resected and postoperative respiratory complications. An institutional database was queried for patients with non-small cell lung cancer that underwent lobectomy with en bloc chest wall resection between 2003 and 2014. Propensity matching was used to identify a cohort of patients who underwent lobectomy via thoracotomy without chest wall resection. Patients were propensity matched on age, gender, smoking history, FEV1, and DLCO. The relationship between number of ribs resected and postoperative respiratory complications (bronchoscopy, re-intubation, pneumonia, or tracheostomy) was examined. Sixty-eight patients (34 chest wall resections; 34 without chest wall resection) were divided into 3 cohorts: cohort A = 0 ribs resected (n = 34), cohort B = 1-3 ribs resected (n = 24), and cohort C = 4-6 ribs resected (n = 10). Patient demographics were similar between cohorts. The 90-day mortality rate was 2.9 % (2/68) and did not vary between cohorts. On multivariate analysis, having 1-3 ribs resected (OR 19.29, 95 % CI (1.33, 280.72); p = 0.03), 4-6 ribs resected [OR 26.66, (1.48, 481.86); p = 0.03), and a lower DLCO (OR 0.91, (0.84, 0.99); p = 0.02) were associated with postoperative respiratory complications. In patients undergoing lobectomy with en bloc chest wall resection for non-small cell lung cancer, the number of ribs resected is directly associated with incidence of postoperative respiratory complications.

Effect of Diluent on Ultra-low Temperature Curable Conductive Silver Adhesive

NASA Astrophysics Data System (ADS)

Zhou, Xingli; Wang, Likun; Liao, Qingwei; Yan, Chao; Du, Haibo; Qin, Lei

2018-03-01

The ultra-low temperature curable conductive silver adhesive needed urgently for the surface conductive treatment of piezoelectric composite material. The effect of diluent acetone on ultra-low temperature curable conductive silver adhesive were investigated for surface conductive treatment of piezoelectric composite material. In order to improve the operability and extend the life of the conductive adhesive, the diluent was added to dissolve and disperse conductive adhesive. With the increase of the content of diluent, the volume resistivity of conductive adhesive decreased at first and then increased, and the shear strength increased at first and then decreased. When the acetone content is 10%, the silver flaky bonded together, arranged the neatest, the smallest gap, the most closely connected, the surface can form a complete conductive network, and the volume resistivity is 2.37 × 10-4Ω · cm, the shear strength is 5.13MPa.

Surgical approach to giant aneurysms of the anterior circulation.

PubMed

Giombini, S; Solero, C L; Ferraresi, S; Melcarne, A; Broggi, G; Pluchino, F

1988-01-01

The surgical approach to cerebral giant aneurysms is still a source of great concern. We describe our experience with giant aneurysms of the anterior circulation and discuss the different surgical techniques adopted. During the period January 1972-December 1985, a total of 33 patients were operated upon at the Istituto Neurologico "C. Besta" of Milan for a giant aneurysm of the anterior circulation. Nineteen cases had suffered subarachnoid haemorrhage before admission; in 14 cases the hospitalization was due to evidence of mass effect on the surrounding neurovascular structures. All aneurysms were directly approached: in 24 cases the neck was occluded by a suitable clip, in 4 cases intramural thrombosis was attempted, in 3 cases the aneurysms were definitively trapped and in one case aneurysmorrhaphy was performed after resection of the sac. Operative mortality was 12%. Long-term follow-up shows good results whenever exclusion of the aneurysm from cerebral circulation had been achieved, either after removal of the sac or not; on the contrary, only fair or poor results were evident when other surgical techniques were adopted, either electively or out of necessity. The importance of intraoperative protection and monitoring of brain function is stressed.

Resection margin and recurrence-free survival after liver resection of colorectal metastases.

PubMed

Muratore, Andrea; Ribero, Dario; Zimmitti, Giuseppe; Mellano, Alfredo; Langella, Serena; Capussotti, Lorenzo

2010-05-01

Optimal margin width is uncertain because of conflicting results from recent studies using overall survival as the end-point. After recurrence, re-resection and aggressive chemotherapy heavily affect survival time; the potential confounding effect of such factors has not been investigated. Use of recurrence-free survival (RFS) may overcome this limitation. The aim of this study is to evaluate the impact of width of resection margin on RFS and site of recurrence after hepatic resection for colorectal metastases (CRM). From a prospectively maintained institutional database (1/1999-12/2007) we identified 314 patients undergone hepatectomy for CRM (1/1999-12/2007) with detailed pathologic analysis of the surgical margin and complete follow-up imaging studies documenting disease status and site of recurrence, which was categorized as: resection margin (M(arg)), other intra-hepatic ((other)IH), lung (L) or other extra-hepatic ((other)EH). Recurrence-free estimation was the survival end-point. Median follow-up was 56.5 months. Two hundred and fifteen patients (68.8%) recurred at 288 sites after a mean of 15.5 months. A positive resection margin was associated with an increased risk of M(arg) recurrence (P < 0.001). The presence of >or=2 metastases was the only factor increasing the risk of positive margins (P < 0.05). The width of the negative resection margin (>or=1 cm versus >1 cm) was not a prognostic factor of worse RFS (30.2% versus 37.3%, P = 0.6). Node status of the primary tumour, and size and number of CRM were independent predictors of RFS. Tumour biology and not the width of the negative resection margin affect RFS.

Histopathological and Postoperative Behavioral Comparison of Rodent Oral Tongue Resection: Fiber-Enabled CO2 Laser versus Electrocautery

PubMed Central

Shires, Courtney Brooke; Saputra, Jennifer Marie; King, Lauren; Thompson, Jerome W.; Heck, Detlef H.; Sebelik, Merry Ellen; Boughter, John Dudley

2015-01-01

Objective To compare operative time and hemostasis of fiber-enabled CO2 laser (FECL) energy to that of the electrocautery (EC) technique for oral tongue resection, to compare return to oral intake and preoperative weight after FECL and EC resection, and to compare histologic changes in adjacent tissue after FECL and EC resection. Study Design Prospective animal study. Setting Research laboratory. Subjects and Methods The CO2 laser fiber and the Bovie cautery were each used to resect the anterior tongue in 15 adult rats. Fixative perfusion and killing were performed on postoperative day 0 (n = 10), 3 (n = 10), or 7 (n = 10). Body weight, food intake, and water intake were recorded daily for 3- and 7-day survival rats. After preparation for histologic analysis, the tongue tissue was graded with a mucosal wound-healing scale (MWHS). Results A higher incidence of intraoperative bleeding and shorter operative times were noted in the EC group. No statistically significant difference in postoperative food or water intake between the EC and FECL groups was noted. The FECL group returned to baseline weight by postoperative day 6. MWHS scores were lower in the EC group by postoperative day 3 and lower in the FECL group by postoperative day 7. Conclusions Both EC and FECL are effective for resection of the tongue in rats. EC has the advantage of shorter operative time and lower MWHS scores by postoperative day 3; FECL has the advantages of less intraoperative bleeding, faster return to baseline body weight, and lower MWHS score by postoperative day 7. PMID:22535916

Noise thermometry at ultra-low temperatures.

PubMed

Rothfuss, D; Reiser, A; Fleischmann, A; Enss, C

2016-03-28

The options for primary thermometry at ultra-low temperatures are rather limited. In practice, most laboratories are using (195)Pt NMR thermometers in the microkelvin range. In recent years, current sensing direct current superconducting quantum interference devices (DC-SQUIDs) have enabled the use of noise thermometry in this temperature range. Such devices have also demonstrated the potential for primary thermometry. One major advantage of noise thermometry is the fact that no driving current is needed to operate the device and thus the heat dissipation within the thermometer can be reduced to a minimum. Ultimately, the intrinsic power dissipation is given by the negligible back action of the readout SQUID. For thermometry in low-temperature experiments, current noise thermometers and magnetic flux fluctuation thermometers have proved to be most suitable. To make use of such thermometers at ultra-low temperatures, we have developed a cross-correlation technique that reduces the amplifier noise contribution to a negligible value. For this, the magnetic flux fluctuations caused by the Brownian motion of the electrons in our noise source are measured inductively by two DC-SQUID magnetometers simultaneously and the signals from these two channels are cross-correlated. Experimentally, we have characterized a thermometer made of a cold-worked high-purity copper cylinder with a diameter of 5 mm and a length of 20 mm for temperatures between 42 μK and 0.8 K. For a given temperature, a measuring time below 1 min is sufficient to reach a precision of better than 1%. The extremely low power dissipation in the thermometer allows continuous operation without heating effects. © 2016 The Author(s).

Preoperative Prediction of the Necessity for Anterior Clinoidectomy During Microsurgical Clipping of Ruptured Posterior Communicating Artery Aneurysms.

PubMed

Kamide, Tomoya; Burkhardt, Jan-Karl; Tabani, Halima; Safaee, Michael M; Lawton, Michael T

2018-01-01

Although most posterior communicating artery (PCoA) aneurysms can be clipped easily with excellent results, some require anterior clinoidectomy for safe and complete clipping. To review our microsurgical series of ruptured PCoA aneurysms and identify the preoperative predictors for anterior clinoidectomy during microsurgical clipping for PCoA aneurysms. Results from microsurgical clipping of 104 patients with ruptured PCoA aneurysms were reviewed retrospectively. Distances and angles were obtained from computed tomographic angiography and compared between the anterior and nonanterior clinoidectomy groups. Anterior clinoidectomy was required in 19 of the 104 cases (18%). None developed surgical complications due to anterior clinoid process (ACP) resection, including postoperative visual deficit. Univariate and multivariate analyses revealed that the distances from the ACP tip to the aneurysmal proximal neck and from the ACP line to the aneurysmal proximal neck were statistically significant predictive factors for the need of anterior clinoidectomy. Based on a receiver operating characteristic analysis, the distances from the ACP tip to the aneurysmal proximal neck <4.0 mm and from the ACP line to the aneurysmal proximal neck ≤2.0 mm were selected as optimal cutoff values for predicting the necessity of anterior clinoidectomy, and the area under the receiver operating characteristic curve values were 0.991 and 0.955, respectively. In case of ruptured PCoA aneurysm surgery, the distances from the ACP tip to the aneurysmal proximal neck and from the ACP line to the aneurysmal proximal neck were both found to be useful predictors of whether anterior clinoidectomy was required. Copyright © 2017 Elsevier Inc. All rights reserved.

Necrotizing odontogenic fasciitis of head and neck extending to anterior mediastinum in elderly patients: innovative treatment with a review of the literature.

PubMed

Cortese, Antonio; Pantaleo, Giuseppe; Borri, Antonio; Amato, Massimo; Claudio, Pier Paolo

2017-02-01

Necrotizing fasciitis (NF) of odontogenic origin affecting the head and neck region is a rare but serious clinical condition, which, if diagnosed late, can lead to a fatal outcome. The early diagnosis of necrotizing fasciitis can be difficult. Delay in diagnosis leads to increase in the area of necrosis with a resulting increase in cosmetic deformity and life-threatening complication. In this study, we present two cases of elderly patients with aggressive NF affecting the neck and anterior mediastinum, which were of odontogenic origin. In the two patients selected necrotic skin and soft tissue were removed and wide exposure was achieved with debridement of the neck at the level of the affected layer of superficial cervical fascia. Saline solution was used as irrigation to treat the patients with acute necrotizing fasciitis. Difficulties in managing this condition with NF extent to deep anterior mediastinum is related to clavicle osteotomy or thoracotomy need with high surgical risks. In our technique, by gentle suction in anterior mediastinum, necrotic tissue resection was possible without any osteotomy need. Suctioning resection technique associated with hyperbaric, metabolic rebalance, and amino acid support in association with three types antibiotic therapy are fundamental points for correct therapy strategy, leading to full recovery and healing of NF patients even if in very unfavorable conditions. Multidisciplinary approach is paramount for proper treatment of this disease.

Costs and resource use following defunctioning stoma in low anterior resection for cancer - A long-term analysis of a randomized multicenter trial.

PubMed

Floodeen, H; Hallböök, O; Hagberg, L A; Matthiessen, P

2017-02-01

Defunctioning stoma in low anterior resection (LAR) for rectal cancer can prevent major complications, but overall cost-effectiveness for the healthcare provider is unknown. This study compared inpatient healthcare resources and costs within 5 years of LAR between two randomized groups of patients undergoing LAR with and without defunctioning stoma. Five-year follow-up of a randomized, multicenter trial on LAR (NCT 00636948) with (stoma; n = 116) or without (no stoma; n = 118) defunctioning stoma comparing inpatient healthcare resources and costs. Unplanned stoma formation, days with stoma, length of hospital stay, reoperations, and total associated inpatient costs were analyzed. Average costs were € 21.663 per patient with defunctioning stoma and € 15.922 per patient without defunctioning stoma within 5 years of LAR, resulting in an average cost-saving of € 5.741. There was no difference between groups regarding the total number of days with any stoma (stoma = 33 398 vs. no stoma = 34 068). The total number of unplanned reoperations were 70 (no stoma) and 32 (stoma); p < 0.001. In the group randomized to no stoma at LAR, 30.5% (36/118) required an unplanned stoma later. Randomization to defunctioning stoma in LAR was more expensive than no stoma, despite the cost-savings associated with a reduced frequency of anastomotic leakage. Both groups required the same total number of days with a stoma within five years of LAR. Copyright © 2016 Elsevier Ltd, BASO ~ The Association for Cancer Surgery, and the European Society of Surgical Oncology. All rights reserved.

Extended resection of the trachea in a patient with cicatricial tracheal stenosis after tracheostomy complicated with esophageal-tracheal fistula and extensive defect of the frontal tracheal wall.

PubMed

Khudaybergenov, Shukhrat; Eshonkhodjaev, Otabek; Abdusalomov, Sodiqjon; Amanov, Bakhrom

2017-03-01

We present a case of one-stage radical surgical treatment of a 24-year-old female patient with cicatricial granulating tracheal stenosis after tracheostomy complicated by esophageal-tracheal fistula and an extensive defect of the anterior wall of the trachea after numerous unsuccessful attempts to correct the narrowing of the trachea and eliminate the fistula by endoscopic and open surgical techniques. The patient underwent extended tracheal resection with end-to-end anastomosis with liquidation of the esophageal-tracheal fistula and elimination of the defect of the anterior wall of the trachea by cervical access.

Surgical technique of en bloc pelvic resection for advanced ovarian cancer.

PubMed

Chang, Suk Joon; Bristow, Robert E

2015-04-01

The aim of this paper was to describe the operative details for en bloc removal of the adnexal tumor, uterus, pelvic peritoneum, and rectosigmoid colon with colorectal anastomosis in advanced epithelial ovarian cancer patients with widespread pelvic involvement. The patient presented with good performance status and huge pelvic tumor extensively infiltrating into adjacent pelvic organs and obliterating the cul-de-sac. The patient underwent en bloc pelvic resection as primary cytoreductive surgery. En bloc pelvic resection procedure is initiated by carrying a circumscribing peritoneal incision to include all pan-pelvic disease within this incision. After retroperitoneal pelvic dissection, the round ligaments and infundibulopelvic ligaments are divided. The ureters are dissected and mobilized from the peritoneum. After dissecting off the anterior pelvic peritoneum overlying the bladder with its tumor nodules, the bladder is mobilized caudally and the vesicovaginal space is developed. The uterine vessels are divided at the level of the ureters, and the paracervical tissues (or parametria) are divided. The proximal sigmoid colon is divided above the most proximal extent of gross tumor using a ligating and dividing stapling device. The sigmoid mesentery is ligated and divided including the superior rectal vessels. The pararectal and retrorectal spaces are further developed and dissected down to the level of the pelvic floor. The posterior dissection is progressed and moves to the right and then to the left of the rectum. The rectal pillars including the middle rectal vessels are ligated and divided. Hysterectomy is completed in a retrograde fashion. The distal rectum is divided using a linear stapler. The specimen is removed en bloc with the uterus, adnexa, pelvic peritoneum, rectosigmoid colon, and tumor masses leaving a macroscopically tumor-free pelvis. Colorectal anastomosis was completed using stapling device. En bloc pelvic resection was performed by total

Subthreshold Schottky-barrier thin-film transistors with ultralow power and high intrinsic gain

NASA Astrophysics Data System (ADS)

Lee, Sungsik; Nathan, Arokia

2016-10-01

The quest for low power becomes highly compelling in newly emerging application areas related to wearable devices in the Internet of Things. Here, we report on a Schottky-barrier indium-gallium-zinc-oxide thin-film transistor operating in the deep subthreshold regime (i.e., near the OFF state) at low supply voltages (<1 volt) and ultralow power (<1 nanowatt). By using a Schottky-barrier at the source and drain contacts, the current-voltage characteristics of the transistor were virtually channel-length independent with an infinite output resistance. It exhibited high intrinsic gain (>400) that was both bias and geometry independent. The transistor reported here is useful for sensor interface circuits in wearable devices where high current sensitivity and ultralow power are vital for battery-less operation.

Ultralow Damping in Nanometer-Thick Epitaxial Spinel Ferrite Thin Films.

PubMed

Emori, Satoru; Yi, Di; Crossley, Sam; Wisser, Jacob J; Balakrishnan, Purnima P; Khodadadi, Behrouz; Shafer, Padraic; Klewe, Christoph; N'Diaye, Alpha T; Urwin, Brittany T; Mahalingam, Krishnamurthy; Howe, Brandon M; Hwang, Harold Y; Arenholz, Elke; Suzuki, Yuri

2018-06-08

Pure spin currents, unaccompanied by dissipative charge flow, are essential for realizing energy-efficient nanomagnetic information and communications devices. Thin-film magnetic insulators have been identified as promising materials for spin-current technology because they are thought to exhibit lower damping compared with their metallic counterparts. However, insulating behavior is not a sufficient requirement for low damping, as evidenced by the very limited options for low-damping insulators. Here, we demonstrate a new class of nanometer-thick ultralow-damping insulating thin films based on design criteria that minimize orbital angular momentum and structural disorder. Specifically, we show ultralow damping in <20 nm thick spinel-structure magnesium aluminum ferrite (MAFO), in which magnetization arises from Fe 3+ ions with zero orbital angular momentum. These epitaxial MAFO thin films exhibit a Gilbert damping parameter of ∼0.0015 and negligible inhomogeneous linewidth broadening, resulting in narrow half width at half-maximum linewidths of ∼0.6 mT around 10 GHz. Our findings offer an attractive thin-film platform for enabling integrated insulating spintronics.

Analysis and Design of Rotors at Ultra-Low Reynolds Numbers

NASA Technical Reports Server (NTRS)

Kunz, Peter J.; Strawn, Roger C.

2003-01-01

Design tools have been developed for ultra-low Reynolds number rotors, combining enhanced actuator-ring / blade-element theory with airfoil section data based on two-dimensional Navier-Stokes calculations. This performance prediction method is coupled with an optimizer for both design and analysis applications. Performance predictions from these tools have been compared with three-dimensional Navier Stokes analyses and experimental data for a 2.5 cm diameter rotor with chord Reynolds numbers below 10,000. Comparisons among the analyses and experimental data show reasonable agreement both in the global thrust and power required, but the spanwise distributions of these quantities exhibit significant deviations. The study also reveals that three-dimensional and rotational effects significantly change local airfoil section performance. The magnitude of this issue, unique to this operating regime, may limit the applicability of blade-element type methods for detailed rotor design at ultra-low Reynolds numbers, but these methods are still useful for evaluating concept feasibility and rapidly generating initial designs for further analysis and optimization using more advanced tools.

Ultralow-threshold multiphoton-pumped lasing from colloidal nanoplatelets in solution

PubMed Central

Li, Mingjie; Zhi, Min; Zhu, Hai; Wu, Wen-Ya; Xu, Qing-Hua; Jhon, Mark Hyunpong; Chan, Yinthai

2015-01-01

Although multiphoton-pumped lasing from a solution of chromophores is important in the emerging fields of nonlinear optofluidics and bio-photonics, conventionally used organic dyes are often rendered unsuitable because of relatively small multiphoton absorption cross-sections and low photostability. Here, we demonstrate highly photostable, ultralow-threshold multiphoton-pumped biexcitonic lasing from a solution of colloidal CdSe/CdS nanoplatelets within a cuvette-based Fabry–Pérot optical resonator. We find that colloidal nanoplatelets surprisingly exhibit an optimal lateral size that minimizes lasing threshold. These nanoplatelets possess very large gain cross-sections of 7.3 × 10−14 cm2 and ultralow lasing thresholds of 1.2 and 4.3 mJ cm−2 under two-photon (λexc=800 nm) and three-photon (λexc=1.3 μm) excitation, respectively. The highly polarized emission from the nanoplatelet laser shows no significant photodegradation over 107 laser shots. These findings constitute a more comprehensive understanding of the utility of colloidal semiconductor nanoparticles as the gain medium in high-performance frequency-upconversion liquid lasers. PMID:26419950

Tolerance to the anticonvulsant effect of morphine in mice: blockage by ultra-low dose naltrexone.

PubMed

Roshanpour, Maryam; Ghasemi, Mehdi; Riazi, Kiarash; Rafiei-Tabatabaei, Neda; Ghahremani, Mohammad Hossein; Dehpour, Ahmad Reza

2009-02-01

The present study evaluated the development of tolerance to the anticonvulsant effect of morphine in a mouse model of clonic seizures induced by pentylenetetrazole, and whether ultra-low doses of the opioid receptor antagonist naltrexone which selectively block G(s) opioid receptors were capable of preventing the observed tolerance. The results showed that the morphine anticonvulsant effect could be subject to tolerance after repeated administration. Both the development and expression of tolerance were inhibited by ultra-low doses of naltrexone, suggesting the possible involvement of G(s)-coupled opioid receptors in the development of tolerance to the anticonvulsant effect of morphine.

Carbon transfer from magnesia-graphite ladle refractories to ultra-low carbon steel

NASA Astrophysics Data System (ADS)

Russo, Andrew Arthur

Ultra-low carbon steels are utilized in processes which require maximum ductility. Increases in interstitial carbon lower the ductility of steel; therefore, it is important to examine possible sources of carbon. The refractory ladle lining is one such source. Ladle refractories often contain graphite for its desirable thermal shock and slag corrosion resistance. This graphite is a possible source of carbon increase in ultra-low carbon steels. The goal of this research is to understand and evaluate the mechanisms by which carbon transfers to ultra-low carbon steel from magnesia-graphite ladle refractory. Laboratory dip tests were performed in a vacuum induction furnace under an argon atmosphere to investigate these mechanisms. Commercial ladle refractories with carbon contents between 4-12 wt% were used to investigate the effect of refractory carbon content. Slag-free dip tests and slag-containing dip tests with varying MgO concentrations were performed to investigate the influence of slag. Carbon transfer to the steel was controlled by steel penetrating into the refractory and dissolving carbon in dip tests where no slag was present. The rate limiting step for this mechanism is convective mass transport of carbon into the bulk steel. No detectable carbon transfer occurred in dip tests with 4 and 6 wt%C refractories without slag because no significant steel penetration occurred. Carbon transfer was controlled by the corrosion of refractory by slag in dip tests where slag was present.

Evidence for degraded low frequency verbal concepts in left resected temporal lobe epilepsy patients.

PubMed

Visser, M; Forn, C; Lambon Ralph, M A; Hoffman, P; Gómez Ibáñez, A; Sunajuán, Ana; Rosell Negre, P; Villanueva, V; Ávila, C

2018-06-01

According to a large neuropsychological and neuroimaging literature, the bilateral anterior temporal lobe (ATL) is a core region for semantic processing. It seems therefore surprising that semantic memory appears to be preserved in temporal lobe epilepsy (TLE) patients with unilateral ATL resection. However, recent work suggests that the bilateral semantic system is relatively robust against unilateral damage and semantic impairments under these circumstances only become apparent with low frequency specific concepts. In addition, neuroimaging studies have shown that the function of the left and right ATLs differ and therefore left or right ATL resection should lead to a different pattern of impairment. The current study investigated hemispheric differences in the bilateral semantic system by comparing left and right resected TLE patients during verbal semantic processing of low frequency concepts. Picture naming and semantic comprehension tasks with varying word frequencies were included to investigate the pattern of impairment. Left but not right TLE patients showed impaired semantic processing, which was particularly apparent on low frequency items. This indicates that, for verbal information, the bilateral semantic system is more sensitive to damage in the left compared to the right ATL, which is in line with theories that attribute a more prominent role to the left ATL due to connections with pre-semantic verbal regions. Copyright © 2018 Elsevier Ltd. All rights reserved.

Collisional quenching at ultralow energies: controlling efficiency with internal state selection.

PubMed

Bovino, S; Bodo, E; Gianturco, F A

2007-12-14

Calculations have been carried out for the vibrational quenching of excited H(2) molecules which collide with Li(+) ions at ultralow energies. The dynamics has been treated exactly using the well-known quantum coupled-channel expansions over different initial vibrational levels. The overall interaction potential has been obtained from the calculations carried out earlier by our group using highly correlated ab initio methods. The results indicate that specific features of the scattering observables, e.g., the appearance of Ramsauer-Townsend minima in elastic channel cross sections and the marked increase of the cooling rates from specific initial states, can be linked to potential properties at vanishing energies (sign and size of scattering lengths) and to the presence of either virtual states or bound states. The suggestion is made such that by selecting the initial state preparation of the molecular partners, the ionic interactions would be amenable to controlling quenching efficiency at ultralow energies.

First-Principles Determination of Ultralow Thermal Conductivity of monolayer WSe2

NASA Astrophysics Data System (ADS)

Zhou, Wu-Xing; Chen, Ke-Qiu

2015-10-01

By using first-principles calculations combined with the phonon Boltzmann transport equation, we systematically investigate the phonon transport of monolayer WSe2. Compared with other 2D materials, the monolayer WSe2 is found to have an ultralow thermal conductivity due to the ultralow Debye frequency and heavy atom mass. The room temperature thermal conductivity for a typical sample size of 1 μm is 3.935  W/m K, which is one order of magnitude lower than that of MoS2. And the room temperature thermal conductivity can be further decreased by about 95% in 10 nm sized samples. Moreover, we also find the ZA phonons have the dominant contribution to the thermal conductivity, and the relative contribution is almost 80% at room temperature, which is remarkably higher than that for monolayer MoS2. This is because the ZA phonons have longer lifetime than that of LA and TA phonons in monolayer WSe2.

Anterior spinal artery syndrome. Paraplegia following segmental ischaemic injury to the spinal cord after oesophagectomy.

PubMed

Djurberg, H; Haddad, M

1995-04-01

A case of unexpected paraplegia after oesophageal resection under general anaesthesia combined with epidural analgesia and intra-operative intercostal block is described. Patients with compromised cardiovascular and respiratory function undergoing thoracic or major abdominal surgery can benefit significantly intra-operatively from a combination of general anaesthesia and regional analgesia. The continued use of regional analgesia into the postoperative period offers even more advantages. General anaesthesia administered before regional analgesia may, however, mask complications related to the regional technique and delay the instigation of corrective measures. The blood supply to the anterior part of the spinal cord, through the artery of Adamkiewicz, may be impaired intra-operatively leading to neurological sequelae known as the anterior spinal artery syndrome, characterised by loss of motor function with intact or partially intact sensory function. Patients at risk of developing the syndrome can be identified pre-operatively.

Complete resection of a rectus abdominis muscle invaded by desmoid tumors and subsequent management with an abdominal binder: a case report.

PubMed

Ogawa, Tatsuhiko

2018-02-07

Desmoid-type fibromatosis is characterized by desmoid tumors, which are benign soft tissue tumors that can be locally aggressive but typically do not metastasize. Desmoid tumors can manifest anywhere in the body, and those in the abdominal cavity account for approximately 30 to 50% of all such tumors. Complete resection with free margins has been the standard treatment, but non-surgical therapies have been implemented recently. However, if tumors are strongly invasive and/or persistently recur, radical surgical resection with free margins remains the primary treatment. Unfortunately, radical resection may cause large abdominal defects and hinder reconstruction. Several reports and recommendations have addressed this issue; however, to the best of our knowledge, few reports have described complete resection and the subsequent reconstruction of the rectus abdominis muscle. A 35-year-old Asian woman presented at our hospital with a chief complaint of abdominal pain. She had abdominal desmoid tumors that required complete resection of her rectus abdominis muscle. Due to necrosis in her own reconstructed tissue, we failed to cover her anterior abdominal wall; thus, we used an abdominal binder as a substitute material to avoid exacerbating the incisional hernia and help her generate intra-abdominal pressure. This case report may be informative and helpful for the treatment of patients with desmoid tumors, as managing desmoid-type fibromatosis is difficult.

Liver resection for colorectal cancer metastases

PubMed Central

Gallinger, S.; Biagi, J.J.; Fletcher, G.G.; Nhan, C.; Ruo, L.; McLeod, R.S.

2013-01-01

Questions Should surgery be considered for colorectal cancer (crc) patients who have liver metastases plus (a) pulmonary metastases, (b) portal nodal disease, or (c) other extrahepatic metastases (ehms)? What is the role of chemotherapy in the surgical management of crc with liver metastases in (a) patients with resectable disease in the liver, or (b) patients with initially unresectable disease in the liver that is downsized with chemotherapy (“conversion”)? What is the role of liver resection when one or more crc liver metastases have radiographic complete response (rcr) after chemotherapy? Perspectives Advances in chemotherapy have improved survival in crc patients with liver metastases. The 5-year survival with chemotherapy alone is typically less than 1%, although two recent studies with folfox or folfoxiri (or both) reported rates of 5%–10%. However, liver resection is the treatment that is most effective in achieving long-term survival and offering the possibility of a cure in stage iv crc patients with liver metastases. This guideline deals with the role of chemotherapy with surgery, and the role of surgery when there are liver metastases plus ehms. Because only a proportion of patients with crc metastatic disease are considered for liver resection, and because management of this patient population is complex, multidisciplinary management is required. Methodology Recommendations in the present guideline were formulated based on a prepublication version of a recent systematic review on this topic. The draft methodology experts, and external review by clinical practitioners. Feedback was incorporated into the final version of the guideline. Practice Guideline These recommendations apply to patients with liver metastases from crc who have had or will have a complete (R0) resection of the primary cancer and who are being considered for resection of the liver, or liver plus specific and limited ehms, with curative intent. 1(a). Patients with liver and lung

A rare cause of dysphagia: compression of the esophagus by an anterior cervical osteophyte due to ankylosing spondylitis.

PubMed

Albayrak, Ilknur; Bağcacı, Sinan; Sallı, Ali; Kucuksen, Sami; Uğurlu, Hatice

2013-09-01

Ankylosing spondylitis (AS) is a chronic inflammatory rheumatological disease affecting the axial skeleton with various extra-articular complications. Dysphagia due to a giant anterior osteophyte of the cervical spine in AS is extremely rare. We present a 48-year-old male with AS suffering from progressive dysphagia to soft foods and liquids. Esophagography showed an anterior osteophyte at C5-C6 resulting in esophageal compression. The patient refused surgical resection of the osteophyte and received conservative therapy. However, after 6 months there was no improvement in dysphagia. This case illustrates that a large cervical osteophyte may be the cause of dysphagia in patients with AS and should be included in the diagnostic workup in early stages of the disease.

[Pelvic reconstructions after bone tumor resection].

PubMed

Anract, Philippe; Biau, David; Babinet, Antoine; Tomeno, Bernard

2014-02-01

The three more frequent primitive malignant bone tumour which concerned the iliac bone are chondrosarcoma, following Ewing sarcoma and osteosarcoma. Wide resection remains the most important part of the treatment associated with chemotherapy for osteosarcoma and the Ewing sarcoma. Iliac wing resections and obdurate ring don't required reconstruction. However, acetabular resections and iliac wing resection with disruption of the pelvic ring required reconstruction to provide acceptable functional result. Acetabular reconstruction remains high technical demanding challenge. After isolated acetabular resection or associated to obdurate ring, our usual method of reconstruction is homolateral proximal femoral autograft and total hip prosthesis but it is possible to also used : saddle prosthesis, Mac Minn prosthesis with auto or allograft, modular prosthesis or custom made prosthesis, massive allograft with or without prosthesis and femoro-ilac arthrodesis. After resection of the iliac wing plus acetabulum, reconstruction can be performed by femoro-obturatrice and femora-sacral arthrodesis, homolateral proximal femoral autograft and prosthesis, femoral medialisation, massive allograft and massive allograft. Carcinological results are lesser than resection for distal limb tumor, local recurrence rate range 17 to 45%. Functional results after Iliac wing and obdurate ring are good. However, acetabular reconstruction provide uncertain functional results. The lesser results arrive after hemipelvic or acetabular and iliac wing resection-reconstruction, especially when gluteus muscles were also resected. The most favourable results arrive after isolated acetabular or acetabular plus obturateur ring resection-reconstruction.

Study of ultra-low emittance design for SPEAR3

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, M. -H.; Huang, X.; Safranek, J.

2015-09-17

Since its 2003 construction, the SPEAR3 synchrotron light source at SLAC has continuously improved its performance by raising beam current, top-off injection, and smaller emittance. This makes SPEAR3 one of the most productive light sources in the world. Now, to further enhance the performance of SPEAR3, we are looking into the possibility of converting SPEAR3 to an ultra-low emittance storage ring within its site constraint.

Endoscopic resection of subepithelial tumors

PubMed Central

Schmidt, Arthur; Bauder, Markus; Riecken, Bettina; Caca, Karel

2014-01-01

Management of subepithelial tumors (SETs) remains challenging. Endoscopic ultrasound (EUS) has improved differential diagnosis of these tumors but a definitive diagnosis on EUS findings alone can be achieved in the minority of cases. Complete endoscopic resection may provide a reasonable approach for tissue acquisition and may also be therapeutic in case of malignant lesions. Small SET restricted to the submucosa can be removed with established basic resection techniques. However, resection of SET arising from deeper layers of the gastrointestinal wall requires advanced endoscopic methods and harbours the risk of perforation. Innovative techniques such as submucosal tunneling and full thickness resection have expanded the frontiers of endoscopic therapy in the past years. This review will give an overview about endoscopic resection techniques of SET with a focus on novel methods. PMID:25512768

Endoscopic resection of subepithelial tumors.

PubMed

Schmidt, Arthur; Bauder, Markus; Riecken, Bettina; Caca, Karel

2014-12-16

Management of subepithelial tumors (SETs) remains challenging. Endoscopic ultrasound (EUS) has improved differential diagnosis of these tumors but a definitive diagnosis on EUS findings alone can be achieved in the minority of cases. Complete endoscopic resection may provide a reasonable approach for tissue acquisition and may also be therapeutic in case of malignant lesions. Small SET restricted to the submucosa can be removed with established basic resection techniques. However, resection of SET arising from deeper layers of the gastrointestinal wall requires advanced endoscopic methods and harbours the risk of perforation. Innovative techniques such as submucosal tunneling and full thickness resection have expanded the frontiers of endoscopic therapy in the past years. This review will give an overview about endoscopic resection techniques of SET with a focus on novel methods.

Surgical management of anterior chamber epithelial cysts.

PubMed

Haller, Julia A; Stark, Walter J; Azab, Amr; Thomsen, Robert W; Gottsch, John D

2003-03-01

To review management strategies for treatment of anterior chamber epithelial cysts. Retrospective review of consecutive interventional case series. Charts of patients treated for epithelial ingrowth over a 10-year period by a single surgeon were reviewed. Cases of anterior chamber epithelial cysts were identified and recorded, including details of ocular history, preoperative and postoperative acuity, intraocular pressure (IOP), and ocular examination, type of surgical intervention, and details of further procedures performed. Seven eyes with epithelial cysts were identified. Patient age ranged from 1.5 to 53 years at presentation. Four patients were children. In four eyes, cysts were secondary to trauma, one case was presumably congenital, one case developed after corneal perforation in an eye with Terrien's marginal degeneration, and one case developed after penetrating keratoplasty (PK). Three eyes were treated with vitrectomy, en bloc resection of the cyst and associated tissue, fluid-air exchange and cryotherapy. The last four eyes were treated with a new conservative strategy of cyst aspiration (three cases) or local excision (one keratin "pearl" cyst), and endolaser photocoagulation of the collapsed cyst wall/base. All epithelial tissue was successfully eradicated by clinical criteria; one case required repeat excision (follow-up, 9 to 78 months, mean 45). Two eyes required later surgery for elevated IOP, two for cataract extraction and one for repeat PK. Final visual acuity ranged from 20/20 to hand motions, depending on associated ocular damage. Best-corrected visual results were obtained in the more conservatively managed eyes. Anterior chamber epithelial cysts can be managed conservatively in selected cases with good results. This strategy may be particularly useful in children's eyes, where preservation of the lens, iris, and other structures may facilitate amblyopia management. Copyright 2003 by Elsevier Science Inc.

A programmable ultra-low noise X-band exciter.

PubMed

MacMullen, A; Hoover, L R; Justice, R D; Callahan, B S

2001-07-01

A programmable ultra-low noise X-band exciter has been developed using commercial off-the-shelf components. Its phase noise is more than 10 dB below the best available microwave synthesizers. It covers a 7% frequency band with 0.1-Hz resolution. The X-band output at +23 dBm is a combination of signals from an X-band sapphire-loaded cavity oscillator (SLCO), a low noise UHF frequency synthesizer, and special-purpose frequency translation and up-conversion circuitry.

Introduction of laparoscopic low anterior resection for rectal cancer early during residency: a single institutional study on short-term outcomes.

PubMed

Ogiso, Satoshi; Yamaguchi, Takashi; Hata, Hiroaki; Kuroyanagi, Hiroya; Sakai, Yoshiharu

2010-11-01

Laparoscopic surgery for rectal cancer is unpopular because it is technically challenging. Suitable training systems have not been widely studied or established despite the steep learning curve for this procedure. We developed a systematic training program that enables resident surgeons to perform laparoscopic low anterior resection (LLAR) for rectal cancer and evaluated the safety and feasibility of this training program. We analyzed prospectively gathered data on all LLARs for rectal cancer performed at a single center over a 7-year period. Patients were assessed for demographic characteristics, tumor characteristics, operative procedure, operative time, blood loss, conversion to open surgery, complications, time to bowel recovery, distal margin, and number of lymph nodes harvested. We compared the early surgical, oncological, and functional outcomes of LLARs performed by expert surgeons with those of LLARs performed by resident surgeons for both intraperitoneal and extraperitoneal rectal cancer. All analyses were performed on an intention-to-treat basis. A total of 137 patients met the inclusion criteria for this study. Of the 75 LLARs for intraperitoneal rectal cancer, 40 were performed by expert surgeons (I-E group) and 35 by resident surgeons (I-R group). Of the 62 LLARs for extraperitoneal rectal cancer, 51 were performed by expert surgeons (E-E group) and 11 by resident surgeons (E-R group). The operative time was longer in the E-R group than in the E-E group. The time to resumption of diet was longer in the I-E group than in the I-R group. The other early outcomes, including blood loss, anastomotic leakage, conversion to open surgery, and number of lymph nodes harvested, were similar in the I-E and I-R groups and in the E-E and E-R groups. Our systematic training program on LLAR for rectal cancer enables resident surgeons to perform this procedure safely early during residency, with acceptable short-term outcomes.

Endoscopic Transsphenoidal Resection of Craniopharyngioma.

PubMed

Liew, Kong Yew; Narayanan, Prepageran; Waran, Vicknes

2018-02-01

Objectives  To demonstrate, step-by-step, the technique and efficacy of endoscopic transsphenoidal approach in resection of a suprasellar craniopharyngioma. Design  The video shows a step-by-step approach to the resection, covering the exposure, access, resection, and confirmation of resection and reconstruction. Setting  The surgery was performed in the University of Malaya Medical Centre, a tertiary referral center in the capital of Malaysia. Participants  Surgery was performed jointly by Professor Prepageran from the department of otorhinolaryngology and Professor Vicknes Waran from the division of neurosurgery. Both surgeons are from the University of Malaya. Video compilation, editing, and voice narration was done by Dr. Kong Yew Liew. Main Outcome Measures  Completeness of resection and avoidance of intra- and postoperative complications. Results  Based on intraoperative views and MRI findings, the tumor was completely resected with the patient suffering only transient diabetes insipidus. Conclusion  Central suprasellar tumors can be removed completely via an endoscopic transsphenoidal approach with minimal morbidity to the patient. The link to the video can be found at: https://youtu.be/ZNIHfk12cYg .

Measurement of untruncated nuclear spin interactions via zero- to ultralow-field nuclear magnetic resonance

NASA Astrophysics Data System (ADS)

Blanchard, J. W.; Sjolander, T. F.; King, J. P.; Ledbetter, M. P.; Levine, E. H.; Bajaj, V. S.; Budker, D.; Pines, A.

2015-12-01

Zero- to ultralow-field nuclear magnetic resonance (ZULF NMR) provides a new regime for the measurement of nuclear spin-spin interactions free from the effects of large magnetic fields, such as truncation of terms that do not commute with the Zeeman Hamiltonian. One such interaction, the magnetic dipole-dipole coupling, is a valuable source of spatial information in NMR, though many terms are unobservable in high-field NMR, and the coupling averages to zero under isotropic molecular tumbling. Under partial alignment, this information is retained in the form of so-called residual dipolar couplings. We report zero- to ultralow-field NMR measurements of residual dipolar couplings in acetonitrile-2-13C aligned in stretched polyvinyl acetate gels. This permits the investigation of dipolar couplings as a perturbation on the indirect spin-spin J coupling in the absence of an applied magnetic field. As a consequence of working at zero magnetic field, we observe terms of the dipole-dipole coupling Hamiltonian that are invisible in conventional high-field NMR. This technique expands the capabilities of zero- to ultralow-field NMR and has potential applications in precision measurement of subtle physical interactions, chemical analysis, and characterization of local mesoscale structure in materials.

Comparison of low- and ultralow-dose computed tomography protocols for quantitative lung and airway assessment.

PubMed

Hammond, Emily; Sloan, Chelsea; Newell, John D; Sieren, Jered P; Saylor, Melissa; Vidal, Craig; Hogue, Shayna; De Stefano, Frank; Sieren, Alexa; Hoffman, Eric A; Sieren, Jessica C

2017-09-01

Quantitative computed tomography (CT) measures are increasingly being developed and used to characterize lung disease. With recent advances in CT technologies, we sought to evaluate the quantitative accuracy of lung imaging at low- and ultralow-radiation doses with the use of iterative reconstruction (IR), tube current modulation (TCM), and spectral shaping. We investigated the effect of five independent CT protocols reconstructed with IR on quantitative airway measures and global lung measures using an in vivo large animal model as a human subject surrogate. A control protocol was chosen (NIH-SPIROMICS + TCM) and five independent protocols investigating TCM, low- and ultralow-radiation dose, and spectral shaping. For all scans, quantitative global parenchymal measurements (mean, median and standard deviation of the parenchymal HU, along with measures of emphysema) and global airway measurements (number of segmented airways and pi10) were generated. In addition, selected individual airway measurements (minor and major inner diameter, wall thickness, inner and outer area, inner and outer perimeter, wall area fraction, and inner equivalent circle diameter) were evaluated. Comparisons were made between control and target protocols using difference and repeatability measures. Estimated CT volume dose index (CTDIvol) across all protocols ranged from 7.32 mGy to 0.32 mGy. Low- and ultralow-dose protocols required more manual editing and resolved fewer airway branches; yet, comparable pi10 whole lung measures were observed across all protocols. Similar trends in acquired parenchymal and airway measurements were observed across all protocols, with increased measurement differences using the ultralow-dose protocols. However, for small airways (1.9 ± 0.2 mm) and medium airways (5.7 ± 0.4 mm), the measurement differences across all protocols were comparable to the control protocol repeatability across breath holds. Diameters, wall thickness, wall area fraction

Knife-assisted snare resection: a novel technique for resection of scarred polyps in the colon.

PubMed

Chedgy, Fergus J Q; Bhattacharyya, Rupam; Kandiah, Kesavan; Longcroft-Wheaton, Gaius; Bhandari, Pradeep

2016-03-01

There have been significant advances in the management of complex colorectal polyps. Previous failed resection or polyp recurrence is associated with significant fibrosis, making endoscopic resection extremely challenging; the traditional approach to these lesions is surgery. The aim of this study was to evaluate the efficacy of a novel, knife-assisted snare resection (KAR) technique in the resection of scarred colonic polyps. This was a prospective cohort study of patients, in whom the KAR technique was used to resect scarred colonic polyps > 2  cm in size. Patients had previously undergone endoscopic mucosal resection (EMR) and developed recurrence, or EMR had been attempted but was aborted as a result of technical difficulty. A total of 42 patients underwent KAR of large (median 40  mm) scarred polyps. Surgery for benign disease was avoided in 38 of 41 patients (93 %). No life-threatening complications occurred. Recurrence was seen in six patients (16 %), five of whom underwent further endoscopic resection. The overall cure rate for KAR in complex scarred colonic polyps was 90 %. KAR of scarred colonic polyps by an expert endoscopist was an effective and safe technique with low recurrence rates. © Georg Thieme Verlag KG Stuttgart · New York.

Pica in a Child with Anterior Cingulate Gyrus Oligodendroglioma: Case Report.

PubMed

Rangwala, Shivani D; Tobin, Matthew K; Birk, Daniel M; Butts, Jonathan T; Nikas, Dimitrios C; Hahn, Yoon S

2017-01-01

The anterior cingulate gyrus (ACG) is a continued focus of research as its exact role in brain function and vast connections with other anatomical locations is not fully understood. A review of the literature illustrates the role the ACG likely plays in cognitive and emotional processing, as well as a modulating role in motor function and goal-oriented behaviors. While lesions of the cingulate gyrus are rare, each new case broadens our understanding of its role in cognitive neuroscience and higher order processing. The authors present the case of an 8-year-old boy with a 1-month history of staring spells, agitated personality, and hyperphagia notable for the consumption of paper, who was found to have a 3-cm tumor in the left ACG. Following surgical resection of the tumor, his aggressive behavior and pica were ameliorated and the patient made an uneventful recovery, with no evidence of recurrence over the last 6 years since surgical resection. Here we discuss a unique behavioral presentation of pica, along with a review of the current literature, to illustrate functions of the ACG relevant to the location of the lesion. © 2017 S. Karger AG, Basel.

Ultralow dose dentomaxillofacial CT imaging and iterative reconstruction techniques: variability of Hounsfield units and contrast-to-noise ratio

PubMed Central

Bischel, Alexander; Stratis, Andreas; Kakar, Apoorv; Bosmans, Hilde; Jacobs, Reinhilde; Gassner, Eva-Maria; Puelacher, Wolfgang; Pauwels, Ruben

2016-01-01

Objective: The aim of this study was to evaluate whether application of ultralow dose protocols and iterative reconstruction technology (IRT) influence quantitative Hounsfield units (HUs) and contrast-to-noise ratio (CNR) in dentomaxillofacial CT imaging. Methods: A phantom with inserts of five types of materials was scanned using protocols for (a) a clinical reference for navigated surgery (CT dose index volume 36.58 mGy), (b) low-dose sinus imaging (18.28 mGy) and (c) four ultralow dose imaging (4.14, 2.63, 0.99 and 0.53 mGy). All images were reconstructed using: (i) filtered back projection (FBP); (ii) IRT: adaptive statistical iterative reconstruction-50 (ASIR-50), ASIR-100 and model-based iterative reconstruction (MBIR); and (iii) standard (std) and bone kernel. Mean HU, CNR and average HU error after recalibration were determined. Each combination of protocols was compared using Friedman analysis of variance, followed by Dunn's multiple comparison test. Results: Pearson's sample correlation coefficients were all >0.99. Ultralow dose protocols using FBP showed errors of up to 273 HU. Std kernels had less HU variability than bone kernels. MBIR reduced the error value for the lowest dose protocol to 138 HU and retained the highest relative CNR. ASIR could not demonstrate significant advantages over FBP. Conclusions: Considering a potential dose reduction as low as 1.5% of a std protocol, ultralow dose protocols and IRT should be further tested for clinical dentomaxillofacial CT imaging. Advances in knowledge: HU as a surrogate for bone density may vary significantly in CT ultralow dose imaging. However, use of std kernels and MBIR technology reduce HU error values and may retain the highest CNR. PMID:26859336

[Duodenum-preserving total pancreatic head resection and pancreatic head resection with segmental duodenostomy].

PubMed

Takada, Tadahiro; Yasuda, Hideki; Nagashima, Ikuo; Amano, Hodaka; Yoshiada, Masahiro; Toyota, Naoyuki

2003-06-01

A duodenum-preserving pancreatic head resection (DPPHR) was first reported by Beger et al. in 1980. However, its application has been limited to chronic pancreatitis because of it is a subtotal pancreatic head resection. In 1990, we reported duodenum-preserving total pancreatic head resection (DPTPHR) in 26 cases. This opened the way for total pancreatic head resection, expanding the application of this approach to tumorigenic morbidities such as intraductal papillary mucinous tumor (IMPT), other benign tumors, and small pancreatic cancers. On the other hand, Nakao et al. reported pancreatic head resection with segmental duodenectomy (PHRSD) as an alternative pylorus-preserving pancreatoduodenectomy technique in 24 cases. Hirata et al. also reported this technique as a new pylorus-preserving pancreatoduodenostomy with increased vessel preservation. When performing DPTPHR, the surgeon should ensure adequate duodenal blood supply. Avoidance of duodenal ischemia is very important in this operation, and thus it is necessary to maintain blood flow in the posterior pancreatoduodenal artery and to preserve the mesoduodenal vessels. Postoperative pancreatic functional tests reveal that DPTPHR is superior to PPPD, including PHSRD, because the entire duodenum and duodenal integrity is very important for postoperative pancreatic function.

Extended resection of the trachea in a patient with cicatricial tracheal stenosis after tracheostomy complicated with esophageal-tracheal fistula and extensive defect of the frontal tracheal wall

PubMed Central

Khudaybergenov, Shukhrat; Abdusalomov, Sodiqjon; Amanov, Bakhrom

2017-01-01

We present a case of one-stage radical surgical treatment of a 24-year-old female patient with cicatricial granulating tracheal stenosis after tracheostomy complicated by esophageal-tracheal fistula and an extensive defect of the anterior wall of the trachea after numerous unsuccessful attempts to correct the narrowing of the trachea and eliminate the fistula by endoscopic and open surgical techniques. The patient underwent extended tracheal resection with end-to-end anastomosis with liquidation of the esophageal-tracheal fistula and elimination of the defect of the anterior wall of the trachea by cervical access. PMID:28515752

Elective hepatic resection in the elderly.

PubMed

Mentha, G; Huber, O; Robert, J; Klopfenstein, C; Egeli, R; Rohner, A

1992-06-01

This retrospective review assessed the safety and validity of elective liver resection in patients older than 64 years of age. In all, 293 patients underwent elective liver resection over a 23-year period (1967-1990). Fifty-two patients (18 per cent) were older than 64 (maximum 84, mean 70.4) years and all but four of these did not have cirrhosis. In this older subgroup, indications for resection were liver metastases in 30 patients, primary malignancy in 16, benign tumours in five and multiple abscesses in one. There were 21 major resections, with two deaths from hepatic failure, and 31 minor resections, with one death from cardiac failure (total mortality rate 6 per cent). During the same period, there were seven deaths after elective resections performed in 222 patients without cirrhosis who were younger than 64 years (P = 0.39). Mortality rate and duration of postoperative hospital stay were not related to the extent of liver resection nor to patients' grading according to the American Society of Anesthesiologists' criteria. Intraoperative blood loss was the only parameter found to influence mortality rate (P = 0.008) and duration of hospital stay (P = 0.04). Elective liver resection can be safely undertaken in elderly patients without cirrhosis, provided that intraoperative blood loss is minimized.

Investigation of the Performance of an Ultralow-Dark-Count Superconducting Nanowire Single-Photon Detector

NASA Astrophysics Data System (ADS)

Subashchandran, Shanthi; Okamoto, Ryo; Zhang, Labao; Tanaka, Akira; Okano, Masayuki; Kang, Lin; Chen, Jian; Wu, Peiheng; Takeuchi, Shigeki

2013-10-01

The realization of an ultralow-dark-count rate (DCR) along with the conservation of high detection efficiency (DE) is critical for many applications using single photon detectors in quantum information technologies, material sciences, and biological sensing. For this purpose, a fiber-coupled superconducting nanowire single-photon detector (SNSPD) with a meander-type niobium nitride nanowire (width: 50 nm) is studied. Precise measurements of the bias current dependence of DE are carried out for a wide spectral range (from 500 to 1650 nm in steps of 50 nm) using a white light source and a laser line Bragg tunable band-pass filter. An ultralow DCR (0.0015 cps) and high DE (32%) are simultaneously achieved by the SNSPD at a wavelength of 500 nm.

Endoscopic resection of gastric submucosal tumors: A comparison of endoscopic nontunneling with tunneling resection and a systematic review.

PubMed

Zhang, Qiang; Wang, Fei; Wei, Gong; Cai, Jian-Qun; Zhi, Fa-Chao; Bai, Yang

2017-01-01

Endoscopic tunneling resection is a relatively novel endoscopic technology for removing gastric submucosal tumors. Our study aimed to compare the differences between tunneling and nontunneling resection for gastric submucosal tumors. Resections of gastric submucosal tumors (n = 97) performed from 2010 to 2015 at our endoscopy center were reviewed, and PubMed was searched for clinical studies on gastric submucosal tumor resection by endoscopic nontunneling and tunneling techniques. At our endoscopy center, nontunneling (Group 1) and tunneling resection (Group 2) were performed for 78 and 19 submucosal tumors, respectively; median tumor diameters were 15 and 20 mm (P = 0.086), median procedural times were 50 and 75 min (P = 0.017), successful resection rates were 94.9% (74/78) and 89.5% (17/19) (P = 0.334), and en bloc resection rates were 95.9% (71/74) and 94.1% (16/17) (P = 0.569) in the Groups 1 and 2, respectively. Postoperative fever, delayed hemorrhage and perforation, hospitalization time, and hospitalization expense were statistically similar between the 2 groups. A literature review on gastric submucosal tumor resection suggested that the en bloc resection rates of the two methods for tumors with a median diameter of 15-30 mm were also high, and there were no relapses during the follow-up period. Both endoscopic nontunneling and tunneling resection seem to be effective and safe methods for removing relatively small gastric submucosal tumors. Compared with endoscopic nontunneling, tunneling resection does not seem to have distinct advantages for gastric submucosal tumors, and has a longer mean operative time.

Anterior Impingement Syndrome of the Ankle Caused by Osteoid Osteoma in the Talar Neck Treated with Arthroscopy and 3D C-Arm-Based Imaging.

PubMed

Ikegami, Masachika; Matsumoto, Takumi; Chang, Song Ho; Kobayashi, Hiroshi; Shinoda, Yusuke; Tanaka, Sakae

2017-01-01

Osteoid osteoma in periarticular lesions tends to have an unusual presentation that likely leads to a delayed or missed diagnosis compared with a typical osteoid osteoma in the metaphysis or diaphysis of the long bone. In cases that are unresponsive to conservative treatment, surgical interventions including en bloc resection, computed tomography-guided percutaneous treatment, and arthroscopic resection have been performed; however, these methods frequently result in inadequate tumor resection and recurrence. Here we present a case of a 16-year-old girl with osteoid osteoma in the talar neck presenting as anterior impingement syndrome due to marked synovitis in the ankle joint which was successfully treated without complications by arthroscopic synovectomy and tumor resection followed by intraoperative 3D C-arm-based imaging confirming complete tumor lesion removal. Her pain was relieved immediately after the surgery, and there was no recurrence at 12 months of follow-up. This is the first case report of the surgical treatment of the osteoid osteoma in the talar neck with the combination methods of arthroscopy and 3D C-arm-based imaging.

Preoperative psychological adjustment and surgical outcome are determinants of psychosocial status after anterior temporal lobectomy.

PubMed Central

Hermann, B P; Wyler, A R; Somes, G

1992-01-01

This investigation evaluated the role of preoperative psychological adjustment, degree of postoperative seizure reduction, and other relevant variables (age, education, IQ, age at onset of epilepsy, laterality of resection) in determining emotional/psychosocial outcome following anterior temporal lobectomy. Ninety seven patients with complex partial seizures of temporal lobe origin were administered the Minnesota Multiphasic Personality Inventory (MMPI), Washington Psychosocial Seizure Inventory (WPSI), and the General Health Questionnaire (GHQ) both before and six to eight months after anterior temporal lobectomy. The data were subjected to a nonparametric rank sum technique (O'Brien's procedure) which combined the test scores to form a single outcome index (TOTAL PSYCHOSOCIAL OUTCOME) that was analysed by multiple regression procedures. Results indicated that the most powerful predictors of patients' overall postoperative psychosocial outcome were: 1) The adequacy of their preoperative psychosocial adjustment, and 2) A totally seizure-free outcome. Additional analyses were carried out separately on the MMPI, WPSI, and GHQ to determine whether findings varied as a function of the specific outcome measure. These results were related to the larger literature concerned with the psychological outcome of anterior temporal lobectomy. PMID:1619418

Comparison of survival outcomes after anatomical resection and non-anatomical resection in patients with hepatocellular carcinoma

PubMed Central

Kim, Seheon; Kim, Seokwhan; Song, Insang

2015-01-01

Backgrounds/Aims Liver resection is a curative procedure performed worldwide for hepatocellular carcinoma (HCC). Deciding on the appropriate resection range for postoperative hepatic function preservation is an important surgical consideration. This study compares survival outcomes of HCC patients who underwent anatomical or non-anatomical resection, to determine which offers the best clinical survival benefit. Methods One hundred and thirty-one patients underwent liver resection with HCC, between January 2007 and February 2015, and were divided into two groups: those who underwent anatomical liver resection (n=88) and those who underwent non-anatomical liver resection (n=43). Kaplan-Meier survival analysis and Cox regressions were used to compare the disease-free survival (DFS) and overall survival (OS) rates between the groups. Results The mean follow-up periods were 27 and 40 months in the anatomical and non-anatomical groups, respectively (p=0.229). The 3- and 5-year DFS rates were 70% and 60% in the anatomical group and 62% and 48% in the non-anatomical group, respectively. The 3 and 5-year OS rates were 94% and 78% in the anatomical group, and 86% and 80% in the non-anatomical group, respectively. The anatomical group tended to show better outcomes, but the findings were not significant. However, a relative risk of OS between the anatomical and non-anatomical group was 0.234 (95% CI, 0.061-0.896; p=0.034), which is statistically significant. Conclusions Although statistical significance was not detected in survival curves, anatomical resection showed better results. In this respect, anatomical resection is more likely to perform in HCC patients with preserve liver function than non-anatomical resection. PMID:26693235

Subthreshold Schottky-barrier thin-film transistors with ultralow power and high intrinsic gain.

PubMed

Lee, Sungsik; Nathan, Arokia

2016-10-21

The quest for low power becomes highly compelling in newly emerging application areas related to wearable devices in the Internet of Things. Here, we report on a Schottky-barrier indium-gallium-zinc-oxide thin-film transistor operating in the deep subthreshold regime (i.e., near the OFF state) at low supply voltages (<1 volt) and ultralow power (<1 nanowatt). By using a Schottky-barrier at the source and drain contacts, the current-voltage characteristics of the transistor were virtually channel-length independent with an infinite output resistance. It exhibited high intrinsic gain (>400) that was both bias and geometry independent. The transistor reported here is useful for sensor interface circuits in wearable devices where high current sensitivity and ultralow power are vital for battery-less operation. Copyright © 2016, American Association for the Advancement of Science.

3D Navigation-guided Resection of Giant Ventral Cervical Intradural Schwannoma With 360-Degree Stabilization.

PubMed

Hussain, Ibrahim; Navarro-Ramirez, Rodrigo; Lang, Gernot; Härtl, Roger

2018-06-01

Giant schwannomas are defined as intradural extramedullary tumors that span >2 vertebral body lengths. Although uncommon, these lesions can cause significant mass effect on the spinal cord and subsequent neurologic compromise. Gross total resection is the goal of operative intervention, however, is extremely challenging in cases where the tumor occupies a ventral, midline position within the lower cervical thecal sac. Using a representative case presentation, we describe an adult male with insidious progression of upper extremity radicular pain and paresthesias, found to have a ventral, solid/cystic C5-C7 giant schwannoma. We demonstrate the step-by-step surgical technique for an anterior approach 2-level cervical corpectomy, microsurgical resection of an intradural giant schwannoma, watertight dural closure, and lastly 360-degrees instrumented stabilization of the cervicothoracic spine. In addition we incorporate the utilization of a portable intraoperative computed tomography for stereotactic localization and 3-dimensional navigation-guided screw implantation. Finally, we discuss various preoperative, perioperative, and postoperative considerations that can have profound impact on successful outcomes.

ULTRA-LOW POWER CO2 SENSOR FOR INTELLIGENT BUILDING CONTROL - PHASE I

EPA Science Inventory

The proposed EPA SBIR Phase I program will create a novel ultra-low power and low-cost microfabricated CO₂ sensor. The initial developments of sensor technology will serve the very large Demand Controlled Ventilation market that has been identified by KWJ and its...

Diffuse Surface Scattering in the Plasmonic Resonances of Ultralow Electron Density Nanospheres.

PubMed

Monreal, R Carmina; Antosiewicz, Tomasz J; Apell, S Peter

2015-05-21

Localized surface plasmon resonances (LSPRs) have recently been identified in extremely diluted electron systems obtained by doping semiconductor quantum dots. Here, we investigate the role that different surface effects, namely, electronic spill-out and diffuse surface scattering, play in the optical properties of these ultralow electron density nanosystems. Diffuse scattering originates from imperfections or roughness at a microscopic scale on the surface. Using an electromagnetic theory that describes this mechanism in conjunction with a dielectric function including the quantum size effect, we find that the LSPRs show an oscillatory behavior in both position and width for large particles and a strong blue shift in energy and an increased width for smaller radii, consistent with recent experimental results for photodoped ZnO nanocrystals. We thus show that the commonly ignored process of diffuse surface scattering is a more important mechanism affecting the plasmonic properties of ultralow electron density nanoparticles than the spill-out effect.

Endoscopic Resection of Gastric Submucosal Tumors: A Comparison of Endoscopic Nontunneling with Tunneling Resection and a Systematic Review

PubMed Central

Zhang, Qiang; Wang, Fei; Wei, Gong; Cai, Jian-Qun; Zhi, Fa-Chao; Bai, Yang

2017-01-01

Background/Aim: Endoscopic tunneling resection is a relatively novel endoscopic technology for removing gastric submucosal tumors. Our study aimed to compare the differences between tunneling and nontunneling resection for gastric submucosal tumors. Materials and Methods: Resections of gastric submucosal tumors (n = 97) performed from 2010 to 2015 at our endoscopy center were reviewed, and PubMed was searched for clinical studies on gastric submucosal tumor resection by endoscopic nontunneling and tunneling techniques. Results: At our endoscopy center, nontunneling (Group 1) and tunneling resection (Group 2) were performed for 78 and 19 submucosal tumors, respectively; median tumor diameters were 15 and 20 mm (P = 0.086), median procedural times were 50 and 75 min (P = 0.017), successful resection rates were 94.9% (74/78) and 89.5% (17/19) (P = 0.334), and en bloc resection rates were 95.9% (71/74) and 94.1% (16/17) (P = 0.569) in the Groups 1 and 2, respectively. Postoperative fever, delayed hemorrhage and perforation, hospitalization time, and hospitalization expense were statistically similar between the 2 groups. A literature review on gastric submucosal tumor resection suggested that the en bloc resection rates of the two methods for tumors with a median diameter of 15–30 mm were also high, and there were no relapses during the follow-up period. Conclusions: Both endoscopic nontunneling and tunneling resection seem to be effective and safe methods for removing relatively small gastric submucosal tumors. Compared with endoscopic nontunneling, tunneling resection does not seem to have distinct advantages for gastric submucosal tumors, and has a longer mean operative time. PMID:28139501

Note: Ultra-low birefringence dodecagonal vacuum glass cell.

PubMed

Brakhane, Stefan; Alt, Wolfgang; Meschede, Dieter; Robens, Carsten; Moon, Geol; Alberti, Andrea

2015-12-01

We report on an ultra-low birefringence dodecagonal glass cell for ultra-high vacuum applications. The epoxy-bonded trapezoidal windows of the cell are made of SF57 glass, which exhibits a very low stress-induced birefringence. We characterize the birefringence Δn of each window with the cell under vacuum conditions, obtaining values around 10(-8). After baking the cell at 150 °C, we reach a pressure below 10(-10) mbar. In addition, each window is antireflection coated on both sides, which is highly desirable for quantum optics experiments and precision measurements.

Encoding Random Hot Spots of a Volume Gold Nanorod Assembly for Ultralow Energy Memory.

PubMed

Dai, Qiaofeng; Ouyang, Min; Yuan, Weiguang; Li, Jinxiang; Guo, Banghong; Lan, Sheng; Liu, Songhao; Zhang, Qiming; Lu, Guang; Tie, Shaolong; Deng, Haidong; Xu, Yi; Gu, Min

2017-09-01

Data storage with ultrahigh density, ultralow energy, high security, and long lifetime is highly desirable in the 21st century and optical data storage is considered as the most promising way to meet the challenge of storing big data. Plasmonic coupling in regularly arranged metallic nanoparticles has demonstrated its superior properties in various applications due to the generation of hot spots. Here, the discovery of the polarization and spectrum sensitivity of random hot spots generated in a volume gold nanorod assembly is reported. It is demonstrated that the two-photon-induced absorption and two-photon-induced luminescence of the gold nanorods adjacent to such hot spots are enhanced significantly because of plasmonic coupling. The polarization, wavelength, and spatial multiplexing of the hot spots can be realized by using an ultralow energy of only a few picojoule per pulse, which is two orders of magnitude lower than the value in the state-of-the-art technology that utilizes isolated gold nanorods. The ultralow recording energy reduces the cross-talk between different recording channels and makes it possible to realize rewriting function, improving significantly both the quality and capacity of optical data storage. It is anticipated that the demonstrated technology can facilitate the development of multidimensional optical data storage for a greener future. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Impulse Excitation Internal Friction Study of Dislocation and Point Defect Interactions in Ultra-Low Carbon Bake-Hardenable Steel

NASA Astrophysics Data System (ADS)

Jung, Il-Chan; Kang, Deok-Gu; De Cooman, Bruno C.

2014-04-01

The simultaneous presence of interstitial solutes and dislocations in an ultra-low carbon bake-hardenable steel gives rise to two characteristic peaks in the internal friction (IF) spectrum: the dislocation-enhanced Snoek peak and the Snoek-Kê-Köster peak. These IF peaks were used to study the dislocation structure developed by the pre-straining and the static strain aging effect of C during the bake-hardening process. A Ti-stabilized interstitial-free steel was used to ascertain the absence of a γ-peak in the IF spectrum of the deformed ultra-low carbon steel. The analysis of the IF data shows clearly that the bake-hardening effect in ultra-low carbon steel is entirely due to atmosphere formation, with the dislocation segment length being the main parameter affecting the IF peak amplitude. Recovery annealing experiments showed that the rearrangement of the dislocation structure lead to the elimination of the C atmosphere.

Ultralow-fatigue shape memory alloy films

NASA Astrophysics Data System (ADS)

Chluba, Christoph; Ge, Wenwei; Lima de Miranda, Rodrigo; Strobel, Julian; Kienle, Lorenz; Quandt, Eckhard; Wuttig, Manfred

2015-05-01

Functional shape memory alloys need to operate reversibly and repeatedly. Quantitative measures of reversibility include the relative volume change of the participating phases and compatibility matrices for twinning. But no similar argument is known for repeatability. This is especially crucial for many future applications, such as artificial heart valves or elastocaloric cooling, in which more than 10 million transformation cycles will be required. We report on the discovery of an ultralow-fatigue shape memory alloy film system based on TiNiCu that allows at least 10 million transformation cycles. We found that these films contain Ti2Cu precipitates embedded in the base alloy that serve as sentinels to ensure complete and reproducible transformation in the course of each memory cycle.

Azygos vein aneurysm resection concomitant with heart valve repair via right thoracotomy.

PubMed

Suzuki, Yota; Kaji, Masahiro; Hirose, Shigemichi; Ohtsubo, Satoshi

2016-12-01

Azygos vein aneurysm is very rare and is usually found incidentally because of its clinical silence. We report a case of recurrent pleural effusion caused by an azygos vein aneurysm in a patient with moderate mitral valve regurgitation (MR) and tricuspid valve regurgitation (TR). Since valve disease is considered a significant precipitating factor for both dyspnoea and pleural effusion, we decided to study the aetiologies of these conditions concomitantly. Azygos vein aneurysm resection in combination with tricuspid and mitral valve repair using cardiopulmonary bypass was performed successfully through a right anterior thoracotomy. The postoperative course was uneventful, and the patient reported improved exercise capacity. © The Author 2016. Published by Oxford University Press on behalf of the European Association for Cardio-Thoracic Surgery. All rights reserved.

[Robotic rectal resection in rectal cancer: short term results in a monocentric prospective study].

PubMed

Bianchi, P; Petz, W; Spinoglio, G; Belotti, D; Bertani, E; Zampino, M G; Crosta, C; Lazzari, R; Andreoni, B

2011-12-01

The aim of this study was to evaluate technical feasibility, oncological safety and short-term clinical results of robotic rectal resection for cancer. From January 2008 to July 2010, 46 patients (27 males and 19 females, median age 69 years, median BMI 24.6 kg/m2) with histologically-proven adenocarcinoma of medium and distal rectum were enrolled in a prospective database. Preoperative assessment was performed with colonoscopy with biopsies, thoraco-abdominal CT scan, pelvic MRI and endorectal-ultrasound (ERUS). In the case of locally advanced non metastatic disease (T3/4 or N1/2), patients received preoperative radiotherapy (45 Grays in 5 weeks) and chemotherapy (oral Capecitabine). The robotic system was a four-arms Da Vinci® (Intuitive Surgical, Sunnyvale, CA, USA); arms position is not modified during the entire surgical procedure. Twenty-five patients received a preoperative radio-chemotherapy. Surgical procedure was an abdomino-perineal amputation in nine patients and an anterior resection in the remaining 37, with temporary ileostomy in 16 cases and a laparoscopic mobilization of splenic flexure in 25. Median operative time was 251 minutes, median time of first bowel movements 1.7 days and median hospital stay 6.7 days. Major complications requiring reoperation verified in 2 patients, while overall complication rate is 15.2%. Median number of harvested lymph nodes per patient was 18; median distance of the tumour from distal resection margin was 2 cm; distance of the tumour from circumferential margin was superior to 1 mm in all of the patients. At a median follow up of 11 months, all patients are alive and disease-free. Robotic rectal resection is a feasible technique which can provide good oncological and short-term clinical results.

Improved performance of Ta2O5-x resistive switching memory by Gd-doping: Ultralow power operation, good data retention, and multilevel storage

NASA Astrophysics Data System (ADS)

Shi, K. X.; Xu, H. Y.; Wang, Z. Q.; Zhao, X. N.; Liu, W. Z.; Ma, J. G.; Liu, Y. C.

2017-11-01

Resistive-switching memory with ultralow-power consumption is very promising technology for next-generation data storage and high-energy-efficiency neurosynaptic chips. Herein, Ta2O5-x-based multilevel memories with ultralow-power consumption and good data retention were achieved by simple Gd-doping. The introduction of a Gd ion, as an oxygen trapper, not only suppresses the generation of oxygen vacancy defects and greatly increases the Ta2O5-x resistance but also increases the oxygen-ion migration barrier. As a result, the memory cells can operate at an ultralow current of 1 μA with the extrapolated retention time of >10 years at 85 °C and the high switching speeds of 10 ns/40 ns for SET/RESET processes. The energy consumption of the device is as low as 60 fJ/bit, which is comparable to emerging ultralow-energy consumption (<100 fJ/bit) memory devices.

Clinical use of endovenous indocyanine green during rectosigmoid segmental resection for endometriosis.

PubMed

Seracchioli, Renato; Raimondo, Diego; Arena, Alessandro; Zanello, Margherita; Mabrouk, Mohamed

2018-06-01

To describe a new use of endovenous indocyanine green (ICG) to allow real-time visualization of bowel perfusion in women with recto-sigmoid endometriosis who may be candidates for segmental resection. Step-by-step explanation of this method using descriptive text and educational video. Tertiary level referral academic center. A nulliparous 36-year-old woman affected by a large rectal endometriotic nodule was referred for severe dysmenorrhea, dyspareunia, hematochezia, and dyschezia, despite progestinic therapy. An intravenous injection of 1.5 mL solution containing 3.75 mg dose of ICG for intraoperative fluorescence imaging. Evaluation of blood perfusion of bowel and rectal endometriosis nodule. Evaluation of neoanastomosis vascularization after bowel resection. The procedure of endometriosis removal was performed using the daVinciXi surgical platform (Intuitive Surgical, Sunnyvale, CA). After ovarian endometriosis removal and adhesiolysis, we identified the endometriosis nodule on the anterior surface of the rectum. Pararectal, rectovaginal, and retrorectal spaces were dissected with a nerve-sparing technique. Indocyanine green was administered through a peripheral line. A near-infrared camera head enabled vision of the colorant after latency of a few seconds. We observed the ischemic area around the rectal nodule and perfusion areas upstream and downstream from the lesion. We selected the transecting line for rectal resection, taking account of this objective evaluation, beyond the limits of macroscopic disease. After direct mechanical anastomosis, we checked the rectal vascularization with ICG. To the best of our knowledge, this is the first reported use of endovenous ICG during a bowel resection for deep endometriosis. Endovenous ICG is proposed during surgery for rectosigmoid endometriosis to assess the perfusion of the bowel and select the transecting line. With ICG fluorescence imaging, we can objectively evaluate whether blood supply to the anastomosis is

Lesional mesial temporal lobe epilepsy and limited resections: prognostic factors and outcome

PubMed Central

Clusmann, H; Kral, T; Fackeldey, E; Blumcke, I; Helmstaedter, C; von Oertzen, J; Urbach, H; Schramm, J

2004-01-01

Objectives: To evaluate the influence of clinical, investigational, surgical, and histopathological factors on postoperative seizure relief in patients with mesial temporal lobe epilepsy (MTLE) due to lesions other than ammonshornsclerosis (AHS). Methods: Of 738 patients operated for TLE, 78 patients underwent limited resections for lesional MTLE (1990–2000). Seventy four patients with a follow up of more than one year were included. The preoperative clinical, neuropsychological, electroencephalogram, and neuroimaging characteristics were prospectively collected in a database. The histopathological material was re-examined. Results: The mean follow up was 49 months. Fifty eight patients were classified as seizure free (78.4% Class I), and six as almost seizure free (8.1% Class II), grouped together as satisfactory seizure control (64 patients, 86.5%). Five patients (6.8%) were categorised in Classes III and IV, respectively. These were grouped as unsatisfactory seizure control (10 patients, 13.5%). Surgical procedures were: 32 amygdalohippocampectomies (AH), 17 partial anterior AH, 15 AH plus polar resection, seven AH plus basal resection, and three AH plus extended temporal lesionectomy. There was no mortality and 2.7% mild permanent morbidity. Seizure relief did neither differ significantly with these approaches, nor with different classes of pathological findings (43 developmental tumours, 12 glial tumours, 10 dysplasias, and nine others). Even operation of dysplasias resulted in 80% satisfactory seizure control. Seizure onset during childhood proved to be a negative predictor for seizure relief (p = 0.020). MRI revealed 73 suspected lesions (98.6%), one dysembryoplastic neuroepithelial tumour was missed, in four cases no structural abnormalities could be confirmed with histopathological exam. Additionally, multifactorial regression revealed the factors "seizure onset after 10 years of age", "presence of complex partial seizures", "absence of a neurological

Surgical Resection and Scarification for Chronic Seroma Post-Ventral Hernia Mesh Repair

PubMed Central

Vasilakis, Vasileios; Cook, Kristin; Wilson, Dorian

2014-01-01

Patient: Male, 52 Final Diagnosis: Seroma Symptoms: Abdominal discomfort • abdominal mass Medication: — Clinical Procedure: Excision and evacuation of the complex seroma Specialty: Surgery Objective: Unusual or unexpected effect of treatment Background: The aim of this report is to present a new surgical approach in the definitive management of challenging cases of abdominal wall seroma following herniorrhaphy with mesh. Case Report: We describe the case of a 56-year-old male with a 4-year history of a complex abdominal wall seroma. He had undergone fluid aspiration twice without success. On physical examination, the mass was supraumbilical and measured 15×10 cm. Computer tomography (CT) scan revealed a complex encapsulated formation overall measuring 10.1×17.3×17.3 cm in AP, transverse, and craniocaudal dimensions, respectively. In this case complete resection was not safe due to the anatomic relationship of the posterior aspect of the pseudocapsule and the mesh. Intraoperatively, the anterior and lateral aspects of the pseudocapsule were resected and an argon beam was used to scarify the residual posterior pseudocapsule and prevent recurrence. This technique was successful in preventing reaccumulation of the seroma. Conclusions: Capsulectomy and scarification of the remnant pseudocapsule is an acceptable and safe surgical option for complex chronic abdominal wall seromas. PMID:25430512

The value of liver resection for focal nodular hyperplasia: resection yes or no?

PubMed

Hau, Hans Michael; Atanasov, Georgi; Tautenhahn, Hans-Michael; Ascherl, Rudolf; Wiltberger, Georg; Schoenberg, Markus Bo; Morgül, Mehmet Haluk; Uhlmann, Dirk; Moche, Michael; Fuchs, Jochen; Schmelzle, Moritz; Bartels, Michael

2015-10-22

Focal nodular hyperplasia (FNH) are benign lesions in the liver. Although liver resection is generally not indicated in these patients, rare indications for surgical approaches indeed exist. We here report on our single-center experience with patients undergoing liver resection for FNH, focussing on preoperative diagnostic algorithms and quality of life (QoL) after surgery. Medical records of 100 consecutive patients undergoing liver resection for FNH between 1992 and 2012 were retrospectively analyzed with regard to diagnostic pathways and indications for surgery. Quality of life (QoL) before and after surgery was evaluated using validated assessment tools. Student's t test, one-way ANOVA, χ (2), and binary logistic regression analyses such as Wilcoxon-Mann-Whitney test were used, as indicated. A combination of at least two preoperative diagnostic imaging approaches was applied in 99 cases, of which 70 patients were subjected to further imaging or tumor biopsy. In most patients, there was more than one indication for liver resection, including tumor-associated symptoms with abdominal discomfort (n = 46, 40.7 %), balance of risk for malignancy/history of cancer (n = 54, 47.8 %/n = 18; 33.3 %), tumor enlargement/jaundice of vascular and biliary structures (n = 13, 11.5 %), such as incidental findings during elective operation (n = 1, 0.9 %). Postoperative morbidity was 19 %, with serious complications (>grade 2, Clavien-Dindo classification) being evident in 8 %. Perioperative mortality was 0 %. Liver resection was associated with a significant overall improvement in general health (very good-excellent: preoperatively 47.4 % vs. postoperatively 68.1 %; p = 0.015). Liver resection remains a valuable therapeutic option in the treatment of either symptomatic FNH or if malignancy cannot finally be ruled out. If clinically indicated, liver resection for FNH represents a safe approach and may lead to significant improvements of QoL especially in

Gut hormone release after intestinal resection.

PubMed Central

Besterman, H S; Adrian, T E; Mallinson, C N; Christofides, N D; Sarson, D L; Pera, A; Lombardo, L; Modigliani, R; Bloom, S R

1982-01-01

To investigate the possible role of gut and pancreatic hormones in the adaptive responses to gut resection, plasma concentrations of the circulating hormones were measured, in response to a test breakfast, in patients with either small or large intestinal resection and in healthy control subjects. In 18 patients with partial ileal resection a significant threefold rise was found in basal and postprandial levels of pancreatic polypeptide, a fourfold increase in motilin, and more than a twofold increase in gastrin and enteroglucagon levels compared with healthy controls. In contrast, nine patients with colonic resection had a threefold rise in levels of pancreatic polypeptide only. One or more of these peptides may have a role in stimulating the adaptive changes found after gut resection. PMID:7117905

Laparoscopic liver resection: Experience based guidelines

PubMed Central

Coelho, Fabricio Ferreira; Kruger, Jaime Arthur Pirola; Fonseca, Gilton Marques; Araújo, Raphael Leonardo Cunha; Jeismann, Vagner Birk; Perini, Marcos Vinícius; Lupinacci, Renato Micelli; Cecconello, Ivan; Herman, Paulo

2016-01-01

Laparoscopic liver resection (LLR) has been progressively developed along the past two decades. Despite initial skepticism, improved operative results made laparoscopic approach incorporated to surgical practice and operations increased in frequency and complexity. Evidence supporting LLR comes from case-series, comparative studies and meta-analysis. Despite lack of level 1 evidence, the body of literature is stronger and existing data confirms the safety, feasibility and benefits of laparoscopic approach when compared to open resection. Indications for LLR do not differ from those for open surgery. They include benign and malignant (both primary and metastatic) tumors and living donor liver harvesting. Currently, resection of lesions located on anterolateral segments and left lateral sectionectomy are performed systematically by laparoscopy in hepatobiliary specialized centers. Resection of lesions located on posterosuperior segments (1, 4a, 7, 8) and major liver resections were shown to be feasible but remain technically demanding procedures, which should be reserved to experienced surgeons. Hand-assisted and laparoscopy-assisted procedures appeared to increase the indications of minimally invasive liver surgery and are useful strategies applied to difficult and major resections. LLR proved to be safe for malignant lesions and offers some short-term advantages over open resection. Oncological results including resection margin status and long-term survival were not inferior to open resection. At present, surgical community expects high quality studies to base the already perceived better outcomes achieved by laparoscopy in major centers’ practice. Continuous surgical training, as well as new technologies should augment the application of laparoscopic liver surgery. Future applicability of new technologies such as robot assistance and image-guided surgery is still under investigation. PMID:26843910

Which patients with resectable pancreatic cancer truly benefit from oncological resection: is it destiny or biology?

PubMed

Zheng, Lei; Wolfgang, Christopher L

2015-01-01

Pancreatic cancer has a dismal prognosis. A technically perfect surgical operation may still not provide a survival advantage for patients with technically resectable pancreatic cancer. Appropriate selection of patients for surgical resections is an imminent issue. Recent studies have provided an important clue on what serum biomarkers may be used to select out the patients who would unlikely benefit from the surgical resection.

Middle infratemporal fossa less invasive approach for radical resection of parapharyngeal tumors: surgical microanatomy and clinical application.

PubMed

Nonaka, Yoichi; Fukushima, Takanori; Watanabe, Kentaro; Sakai, Jun; Friedman, Allan H; Zomorodi, Ali R

2016-01-01

Surgery of the infratemporal fossa (ITF) and parapharyngeal area presents a formidable challenge to the surgeon due to its anatomical complexity and limited access. Conventional surgical approaches to these regions were often too invasive and necessitate sacrifice of normal function and anatomy. To describe a less invasive transcranial extradural approach to ITF parapharyngeal lesions and to determine its advantages, 17 patients with ITF parapharyngeal neoplasms who underwent tumor resection via this approach were enrolled in the study. All lesions located in the ITF precarotid parapharyngeal space were resected through a small operative corridor between the trigeminal nerve third branch (V3) and the temporomandibular joint (TMJ). Surgical outcomes and postoperative complications were evaluated. Pathological diagnosis included schwannoma in eight cases, paraganglioma in two cases, gangliocytoma in two cases, carcinosarcoma in one case, giant cell tumor in one case, pleomorphic adenoma in one case, chondroblastoma in one case, and juvenile angiofibroma in one case. Gross total resection was achieved in 12 cases, near-total and subtotal resection were in 3 and 2 cases, respectively. The most common postoperative complication was dysphagia. Surgical exposure can be customized from minimal (drilling of retrotrigeminal area) to maximal (full skeletonization of V3, removal of all structures lying lateral to the petrous segment of internal carotid artery) according to tumor size and location. Since the space between the V3 and TMJ is the main corridor of this approach, the key maneuver is the anterior translocation of V3 to obtain an acceptable surgical field.

Duodenal endoscopic full-thickness resection (with video).

PubMed

Schmidt, Arthur; Meier, Benjamin; Cahyadi, Oscar; Caca, Karel

2015-10-01

Endoscopic resection of duodenal non-lifting adenomas and subepithelial tumors is challenging and harbors a significant risk of adverse events. We report on a novel technique for duodenal endoscopic full-thickness resection (EFTR) by using an over-the-scope device. Data of 4 consecutive patients who underwent duodenal EFTR were analyzed retrospectively. Main outcome measures were technical success, R0 resection, histologic confirmation of full-thickness resection, and adverse events. Resections were done with a novel, over-the-scope device (full-thickness resection device, FTRD). Four patients (median age 60 years) with non-lifting adenomas (2 patients) or subepithelial tumors (2 patients) underwent EFTR in the duodenum. All lesions could be resected successfully. Mean procedure time was 67.5 minutes (range 50-85 minutes). Minor bleeding was observed in 2 cases; blood transfusions were not required. There was no immediate or delayed perforation. Mean diameter of the resection specimen was 28.3 mm (range 22-40 mm). Histology confirmed complete (R0) full-thickness resection in 3 of 4 cases. To date, 2-month endoscopic follow-up has been obtained in 3 patients. In all cases, the over-the-scope clip was still in place and could be removed without adverse events; recurrences were not observed. EFTR in the duodenum with the FTRD is a promising technique that has the potential to spare surgical resections. Modifications of the device should be made to facilitate introduction by mouth. Prospective studies are needed to further evaluate efficacy and safety for duodenal resections. Copyright © 2015 American Society for Gastrointestinal Endoscopy. Published by Elsevier Inc. All rights reserved.

Thermally tunable silicon racetrack resonators with ultralow tuning power.

PubMed

Dong, Po; Qian, Wei; Liang, Hong; Shafiiha, Roshanak; Feng, Dazeng; Li, Guoliang; Cunningham, John E; Krishnamoorthy, Ashok V; Asghari, Mehdi

2010-09-13

We present thermally tunable silicon racetrack resonators with an ultralow tuning power of 2.4 mW per free spectral range. The use of free-standing silicon racetrack resonators with undercut structures significantly enhances the tuning efficiency, with one order of magnitude improvement of that for previously demonstrated thermo-optic devices without undercuts. The 10%-90% switching time is demonstrated to be ~170 µs. Such low-power tunable micro-resonators are particularly useful as multiplexing devices and wavelength-tunable silicon microcavity modulators.

Bowel resection for deep endometriosis: a systematic review.

PubMed

De Cicco, C; Corona, R; Schonman, R; Mailova, K; Ussia, A; Koninckx, Pr

2011-02-01

deep endometriosis involving the bowel often is treated by segmental bowel resection. In a recent review of over 10000 segmental bowel resections for indications other than endometriosis, low rectum resections, in particular, were associated with a high long-term complication rate for bladder, bowel and sexual function. to review systematically segmental bowel resections for endometriosis for indications, outcome and complications according to the level of resection and the volume of the nodule. all published articles on segmental bowel resection for endometriosis identified through MEDLINE, EMBASE and ISI Web of Knowledge databases during 1997-2009. the terms 'bowel', 'rectal', 'colorectal', 'rectovaginal', 'rectosigmoid', 'resection' and 'endometriosis' were used. Articles describing more than five bowel resections for endometriosis, and with details of at least three of the relevant endpoints. data did not permit a meaningful meta-analysis. thirty-four articles were found describing 1889 bowel resections. The level of bowel resection and the size of the lesions were poorly reported. The indications to perform a bowel resection were variable and were rarely described accurately. The duration of surgery varied widely and endometriosis was not always confirmed by pathology. Although not recorded prospectively, pain relief was systematically reported as excellent for the first year after surgery. Recurrence of pain was reported in 45 of 189 women; recurrence requiring reintervention occurred in 61 of 314 women. Recurrence of endometriosis was reported in 37 of 267 women. The complication rate was comparable with that of bowel resection for indications other than endometriosis. Data on sexual function were not found. after a systematic review, it was found that the indication to perform a segmental resection was poorly documented and the data did not permit an analysis of indication and outcome according to localisation or diameter of the endometriotic nodule

Kinematics of ACL and anterolateral ligament. Part II: anterolateral and anterior cruciate ligament reconstruction.

PubMed

Bonanzinga, T; Signorelli, C; Grassi, A; Lopomo, N; Jain, M; Mosca, M; Iacono, F; Marcacci, M; Zaffagnini, S

2017-04-01

To quantify the influence of Single-Bundle with Lateral Plasty and Double-Bundle reconstruction on static and dynamic laxity in combined ACL- and ALL-deficient knees. The study included 10 fresh-frozen human knees. The joints were analyzed in the following conditions: ACL + ALL resection, Single-Bundle with Lateral Plasty (SBLP) reconstruction, Double-Bundle (DB) reconstruction. Testing parameters were: anterior displacement at 30° and 90° of flexion (AP30, AP90) applying a manual maximum load; internal rotation at 30° and 90° of flexion (INT30, INT90) applying a 5 Nm torque and acceleration and internal rotation Pivot-Shift (PS) test. Kinematics was acquired by a navigation system. Paired Student's t test was conducted to assess statistical difference (P < 0.05). At both 30° and 90° of knee flexion, both SBLP and DB surgical techniques showed a significant reduction (P < 0.01) of anterior-posterior tibial displacement compared to the resection of ACL + ALL. At 30° on knee flexion it is the SBLP that allows the greatest reduction of internal rotational laxity when compared to DB reconstruction. Concerning the PS test, only SBPL procedure had a significant laxity decrease considering the acceleration reached by the joint when compared with the ACL + ALL state (P < 0.01). Clinical relevance of this study is that the internal rotation and PS test were more efficiently controlled by the SBLP technique than by the DB one at both 30° and 90° of flexion in case of ACL + ALL lesions.

Effects of ultralow oxygen and vacuum treatments on bed bug (Heteroptera: Cimicidae) survival

USDA-ARS?s Scientific Manuscript database

Control of bed bugs has always been problematic, balancing among efficacy, safety, and cost. In this study, ultralow oxygen (ULO) and vacuum treatments were tested on bed bugs to develop a safer, effective, and environmental friendly solution to bed bug infestations. ULO treatments were establishe...

Circumferential resection margin positivity after preoperative chemoradiotherapy based on magnetic resonance imaging for locally advanced rectal cancer: implication of boost radiotherapy to the involved mesorectal fascia.

PubMed

Kim, Kyung Hwan; Park, Min Jung; Lim, Joon Seok; Kim, Nam Kyu; Min, Byung Soh; Ahn, Joong Bae; Kim, Tae Il; Kim, Ho Geun; Koom, Woong Sub

2016-04-01

To identify patients who are at a higher risk of pathologic circumferential resection margin involvement using preoperative magnetic resonance imaging. Between October 2008 and November 2012, 165 patients with locally advanced rectal cancer (cT4 or cT3 with <2 mm distance from tumour to mesorectal fascia) who received preoperative chemoradiotherapy were analysed. The morphologic patterns on post-chemoradiotherapy magnetic resonance imaging were categorized into five patterns from Pattern A (most-likely negative pathologic circumferential resection margin) to Pattern E (most-likely positive pathologic circumferential resection margin). In addition, the location of mesorectal fascia involvement was classified as lateral, posterior and anterior. The diagnostic accuracy of the morphologic criteria was calculated using receiver operating characteristic curve analysis. Pathologic circumferential resection margin involvement was identified in 17 patients (10.3%). The diagnostic accuracy of predicting pathologic circumferential resection margin involvement was 0.73 using the five-scale magnetic resonance imaging pattern. The sensitivity, specificity, positive predictive value and negative predictive value for predicting pathologic circumferential resection margin involvement were 76.5, 65.5, 20.3 and 96.0%, respectively, when cut-off was set between Patterns C and D. On multivariate logistic regression, the magnetic resonance imaging patterns D and E (P= 0.005) and posterior or lateral mesorectal fascia involvement (P= 0.017) were independently associated with increased probability of pathologic circumferential resection margin involvement. The rate of pathologic circumferential resection margin involvement was 30.0% when the patient had Pattern D or E with posterior or lateral mesorectal fascia involvement. Patients who are at a higher risk of pathologic circumferential resection margin involvement can be identified using preoperative magnetic resonance imaging although

Hepatic resection for colorectal metastases - a national perspective.

PubMed Central

Heriot, A. G.; Reynolds, J.; Marks, C. G.; Karanjia, N.

2004-01-01

BACKGROUND: Many consultant surgeons are uncertain about peri-operative assessment and postoperative follow-up of patients for colorectal liver metastases, and indications for referral for hepatic resection. The aim of this study was to assess the views the consultant surgeons who manage these patients. METHODS: A postal questionnaire was sent to all consultant members of the Association of Coloproctology of Great Britain and Ireland and of the Association of Upper Gastrointestinal Surgeons of Great Britain and Ireland. The questionnaire assessed current practice for preoperative assessment and follow-up of patients with colorectal malignancy and timing of and criteria for hepatic resection of metastases. Number of referrals/resections were also assessed. RESULTS: The response rate was 47%. Half of the consultants held joint clinics with an oncologist and 89% assessed the liver for secondaries prior to colorectal resection. Ultrasound was used by 75%. Whilst 99% would consider referring a patient with a solitary liver metastasis for resection, only 62% would consider resection for more than 3 unilobar metastases. The majority (83%) thought resections should be performed within the 6 months following colorectal resection. During follow-up, 52% requested blood CEA levels and 72% liver ultrasound. Half would consider chemotherapy prior to liver resection and 76% performed at least one hepatic resection per year with a median number of 2 resections each year. CONCLUSIONS: A substantial proportion of patients are assessed for colorectal liver metastases preoperatively and during follow-up though there is spectrum of frequency of assessment and modality for imaging. Virtually all patients with solitary hepatic metastases are considered for liver resection. Patients with more than one metastasis are likely to be not considered for resection. Many surgeons are carrying out less than 3 resections each year. PMID:15527578

Four years’ experience in uniportal video-assisted thoracoscopic surgery for major lung resections: influence of silicosis in clinical outcomes

PubMed Central

Pérez Méndez, Itzell

2016-01-01

Background Crystalline silica (CS) is one of the most common minerals and a common particulate air pollutant in both working and living environments. Lung cancer is considered one of the serious consequences of silica exposure. This paper gives an overview of the role of silicosis in results of perioperative and postoperative of lung resection surgery performed by the most up to date video-assisted thoracoscopic surgery (VATS) approach: the uniportal VATS. Methods In January 2012 a program of video-assisted thoracoscopic anatomic pulmonary resections through a uniportal approach (no rib spreading) was started in our institution by a single surgeon experienced in postero-lateral open major resections and in other VATS procedures except lobectomies. We have retrospectively reviewed our first 4 years of experience in which 128 consecutive patients had undergone this approach, setting as a variable comparison of the results the presence of silicosis. Results Between January 2012 to December 2015, 128 anatomical resections where attempted. Of these attempted major resections, 115 (90%) were successfully completed. Out of 128 patients 21 (16%) had a diagnosis of complex silicosis. The most frequent resection was left upper lobectomy. The mean surgical time was 178±65 min. The median postoperative chest drain time was 3 days and the median postoperative hospital stay time was 3 days. There were 25 (19%) minor complications 17 (68%) of them in the first year of experience, and 3 (2.3%) had major complications. Preoperative forced expiratory volume in one second (FEV1) less than 60%, diagnosis of chronic obstructive pulmonary disease (COPD) and silicosis have been predictive of postoperative minor complications. Conclusions The uniportal VATS for major anatomic lung resections is reproducible and safe with good results when performed by surgeons experienced in both open major resections (anterior or postero-lateral thoracotomy), and multiport VATS minor procedures, even in

Improvement of spin-exchange optical pumping of xenon-129 using in situ NMR measurement in ultra-low magnetic field

NASA Astrophysics Data System (ADS)

Takeda, Shun; Kumagai, Hiroshi

2018-02-01

Hyperpolarized (HP) noble gas has attracted attention in NMR / MRI. In an ultra-low magnetic field, the effectiveness of signal enhancement by HP noble gas should be required because reduction of the signal intensity is serious. One method of generating HP noble gas is spin exchange optical pumping which uses selective excitation of electrons of alkali metal vapor and spin transfer to nuclear spin by collision to noble gas. Although SEOP does not require extreme cooling or strong magnetic field, generally it required large-scale equipment including high power light source to generate HP noble gas with high efficiency. In this study, we construct a simply generation system of HP xenon-129 by SEOP with an ultralow magnetic field (up to 1 mT) and small-scale light source (about 1W). In addition, we measure in situ NMR signal at the same time, and then examine efficient conditions for SEOP in ultra-low magnetic fields.

Comparative analysis of gas and coal-fired power generation in ultra-low emission condition using life cycle assessment (LCA)

NASA Astrophysics Data System (ADS)

Yin, Libao; Liao, Yanfen; Liu, Guicai; Liu, Zhichao; Yu, Zhaosheng; Guo, Shaode; Ma, Xiaoqian

2017-05-01

Energy consumption and pollutant emission of natural gas combined cycle power-generation (NGCC), liquefied natural gas combined cycle power-generation (LNGCC), natural gas combined heat and power generation (CHP) and ultra-supercritical power generation with ultra-low gas emission (USC) were analyzed using life cycle assessment method, pointing out the development opportunity and superiority of gas power generation in the period of coal-fired unit ultra-low emission transformation. The results show that CO2 emission followed the order: USC>LNGCC>NGCC>CHP the resource depletion coefficient of coal-fired power generation was lower than that of gas power generation, and the coal-fired power generation should be the main part of power generation in China; based on sensitivity analysis, improving the generating efficiency or shortening the transportation distance could effectively improve energy saving and emission reduction, especially for the coal-fired units, and improving the generating efficiency had a great significance for achieving the ultra-low gas emission.

Postoperative stereotactic radiosurgery for resected brain metastases: A comparison of outcomes for large resection cavities.

PubMed

Zhong, Jim; Ferris, Matthew J; Switchenko, Jeffrey; Press, Robert H; Buchwald, Zachary; Olson, Jeffrey J; Eaton, Bree R; Curran, Walter J; Shu, Hui-Kuo G; Crocker, Ian R; Patel, Kirtesh R

Although historical trials have established the role of surgical resection followed by whole brain irradiation (WBRT) for brain metastases, WBRT has recently been shown to cause significant neurocognitive decline. Many practitioners have employed postoperative stereotactic radiosurgery (SRS) to tumor resection cavities to increase local control without causing significant neurocognitive sequelae. However, studies analyzing outcomes of large brain metastases treated with resection and postoperative SRS are lacking. Here we compare outcomes in patients with large brain metastases >4 cm to those with smaller metastases ≤4 cm treated with surgical resection followed by SRS to the resection cavity. Consecutive patients with brain metastases treated at our institution with surgical resection and postoperative SRS were retrospectively reviewed. Patients were stratified into ≤4 cm and >4 cm cohorts based on preoperative maximal tumor dimension. Cumulative incidence of local failure, radiation necrosis, and death were analyzed for the 2 cohorts using a competing-risk model, defined as the time from SRS treatment date to the measured event, death, or last follow-up. A total of 117 consecutive cases were identified. Of these patients, 90 (77%) had preoperative tumors ≤4 cm, and 27 (23%) >4 cm in greatest dimension. The only significant baseline difference between the 2 groups was a higher proportion of patients who underwent gross total resection in the ≤4 cm compared with the >4 cm cohort, 76% versus 48%, respectively (P <.01). The 1-year rates of local failure, radiation necrosis, and overall survival for the ≤4 cm and >4 cm cohorts were 12.3% and 16.0%, 26.9% and 28.4%, and 80.6% and 67.6%, respectively (all P >.05). The rates of local failure and radiation necrosis were not statistically different on multivariable analysis based on tumor size. Brain metastases >4 cm in largest dimension managed by resection and radiosurgery to the tumor cavity have promising

Note: Ultra-low birefringence dodecagonal vacuum glass cell

DOE Office of Scientific and Technical Information (OSTI.GOV)

Brakhane, Stefan, E-mail: brakhane@iap.uni-bonn.de; Alt, Wolfgang; Meschede, Dieter

We report on an ultra-low birefringence dodecagonal glass cell for ultra-high vacuum applications. The epoxy-bonded trapezoidal windows of the cell are made of SF57 glass, which exhibits a very low stress-induced birefringence. We characterize the birefringence Δn of each window with the cell under vacuum conditions, obtaining values around 10{sup −8}. After baking the cell at 150 °C, we reach a pressure below 10{sup −10} mbar. In addition, each window is antireflection coated on both sides, which is highly desirable for quantum optics experiments and precision measurements.

GaN on Diamond with Ultra-Low Thermal Barrier Resistance

DTIC Science & Technology

2016-03-31

GaN-on-Diamond with Ultra-Low Thermal Barrier Resistance Xing Gu1, Cathy Lee1, Jinqiao Xie1, Edward Beam1, Michael Becker2, Timothy A. Grotjohn2...Bristol BS8 1TL, UK Abstract: We investigated the effective thermal boundary resistance (TBReff) of GaN-on-Diamond interfaces for diamond growth... thermal boundary resistance; TBReff , interfacial layers; high density dielectric Introduction While GaN-based RF transistors, typically on SiC

Frequency up-converted piezoelectric energy harvester for ultralow-frequency and ultrawide-frequency-range operation

NASA Astrophysics Data System (ADS)

Zhang, Xiyang; Gao, Shiqiao; Li, Dongguang; Jin, Lei; Wu, Qinghe; Liu, Feng

2018-04-01

At present, frequency up-converted piezoelectric energy harvesters are disadvantaged by their narrow range of operating frequencies and low efficiency at ultralow-frequency excitation. To address these shortcomings, we propose herein an impact-driven frequency up-converted piezoelectric energy harvester composed of two driving beams and a generating beam. We find experimentally that the proposed device offers efficient energy output over an ultrawide-frequency-range and performs very well in the ultralow-frequency excitation. A maximum peak power of 29.3 mW is achieved under 0.5g acceleration at the excitation frequency of 12.7 Hz. The performance of the energy harvester can be adjusted and optimized by adjusting the spacing between the driving and generating beams. The results show that the proposed harvester has the potential to power miniaturized portable devices and wireless sensor nodes.

Anterior fibrous bundle: a cause of residual pain and restrictive plantar flexion following ankle sprain.

PubMed

Miyamoto, Wataru; Takao, Masato; Matsushita, Takashi

2013-06-01

To describe anterior fibrous bundle as an intra-articular residual disorder following ankle sprain. Between January 1998 and January 2009, we performed arthroscopy on 10 patients (7 males, 3 females; median age, 25 years; age range, 17-43 years) who had the uncommon problem of anterior ankle pain accompanied by restriction of plantar flexion following an ankle sprain. Pre-operative magnetic resonance imaging revealed osteochondral lesions (OCLs) of the talar dome in 3 patients, but no other findings that could explain restricted plantar flexion. All patients underwent arthroscopy for investigation and treatment of the cause of symptoms, and the 3 patients with OCL underwent additional arthroscopic drilling. Outcome was measured using the American Orthopedic Foot and Ankle Society Ankle-Hindfoot Scale (AOFAS) score, Visual Analogue Scale (VAS) for pain and active plantar flexion angle. In all patients, an anterior fibrous bundle was confirmed under arthroscopic investigation as the cause of symptoms and was resected arthroscopically. Median AOFAS and VAS scores improved significantly from 65 (range 61-82) and 70 (range 50-85) pre-operatively to 95 (range 84-100) and 4 (range 0-15) at final follow-up, respectively (p < 0.001). In addition, median active plantar flexion angle improved significantly from 40° (range 35-40) pre-operatively to 55° (range 45-55), (p < 0.01). An anterior fibrous bundle is one of the intra-articular residual disorders after ankle sprain that can cause restriction of plantar flexion.

Borderline resectable pancreatic cancer: Definitions and management

PubMed Central

Lopez, Nicole E; Prendergast, Cristina; Lowy, Andrew M

2014-01-01

Pancreatic cancer is the fourth leading cause of cancer death in the United States. While surgical resection remains the only curative option, more than 80% of patients present with unresectable disease. Unfortunately, even among those who undergo resection, the reported median survival is 15-23 mo, with a 5-year survival of approximately 20%. Disappointingly, over the past several decades, despite improvements in diagnostic imaging, surgical technique and chemotherapeutic options, only modest improvements in survival have been realized. Nevertheless, it remains clear that surgical resection is a prerequisite for achieving long-term survival and cure. There is now emerging consensus that a subgroup of patients, previously considered poor candidates for resection because of the relationship of their primary tumor to surrounding vasculature, may benefit from resection, particularly when preceded by neoadjuvant therapy. This stage of disease, termed borderline resectable pancreatic cancer, has become of increasing interest and is now the focus of a multi-institutional clinical trial. Here we outline the history, progress, current treatment recommendations, and future directions for research in borderline resectable pancreatic cancer. PMID:25152577

Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study.

PubMed

Vogel, Michael W; Giorni, Andrea; Vegh, Viktor; Pellicer-Guridi, Ruben; Reutens, David C

2016-01-01

We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20-50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably.

[Application of hepatic segment resection combined with rigid choledochoscope in the treatment of complex hepatolithiasis guided by three-dimensional visualization technology].

PubMed

Xiang, Nan; Fang, Chihua

2015-05-01

To study the value of hepatic segment resection combined with rigid choledochoscope by the three-dimensional (3D) visualization technology in the diagnosis and treatment of complex hepatolithiasis. Enhance computed tomography (CT) data of 46 patients with complex hepatolithiasis who were admitted to the Zhujiang Hospital of the Southern Medical University from July 2010 to June 2014 were collected.All of the CT data were imported into the medical image three-dimensional visualization system (MI-3DVS) for 3D reconstruction and individual 3D types. The optimal scope of liver resection and the remnant liver volume were determined according to the individualized liver segments which were made via the distribution and variation of hepatic vein and portal vein, the distribution of bile duct stones and stricture of the bile duct, which provided guidance for intraoperative hepatic lobectomy and rigid choledochoscope for the remnant calculus lithotripsy. Outcomes of individual 3D types: 10 cases of type I, 11 cases of IIa, 23 cases of IIb, 2 cases of IIc, 19 cases coexisted with history of biliary surgery. The variation of hepatic artery was appeared 6 cases. The variation of portal vein was appeared 8 cases. The remaining liver volume for virtual hepatic lobectomy controlled more than 50%. Eighteen cases underwent left lateral hepatectomy, 8 cases underwent left liver resection, 8 cases underwent right posterior lobe of liver resection, 4 cases underwent the right hepatic resection, 4 cases underwent IV segment liver resection, 2 cases underwent right anterior lobe of liver resection, 2 cases underwent left lateral hepatectomy combined with right posterior lobe of liver resection, 26 cases underwent targeting treatment of rapid choledochoscope and preumatic lithotripsy. The actual surgical procedure was consistent with the preoperative surgical planning. There was no postoperative residual liver ischemia,congestion, liver failure occurred in this study. The intraoperative

Predictors of seizure freedom after incomplete resection in children.

PubMed

Perry, M S; Dunoyer, C; Dean, P; Bhatia, S; Bavariya, A; Ragheb, J; Miller, I; Resnick, T; Jayakar, P; Duchowny, M

2010-10-19

Incomplete resection of the epileptogenic zone (EZ) is the most important predictor of poor outcome after resective surgery for intractable epilepsy. We analyzed the contribution of preoperative and perioperative variables including MRI and EEG data as predictors of seizure-free (SF) outcome after incomplete resection. We retrospectively reviewed patients <18 years of age with incomplete resection for epilepsy with 2 years of follow-up. Fourteen preoperative and perioperative variables were compared in SF and non-SF (NSF) patients. We compared lesional patients, categorized by reason for incompleteness, to lesional patients with complete resection. We analyzed for effect of complete EEG resection on SF outcome in patients with incompletely resected MRI lesions and vice versa. Eighty-three patients with incomplete resection were included with 41% becoming SF. Forty-eight lesional patients with complete resection were included. Thirty-eight percent (57/151) of patients with incomplete resection and 34% (47/138) with complete resection were excluded secondary to lack of follow-up or incomplete records. Contiguous MRI lesions were predictive of seizure freedom after incomplete resection. Fifty-seven percent of patients incomplete by MRI alone, 52% incomplete by EEG alone, and 24% incomplete by both became SF compared to 77% of patients with complete resection (p = 0.0005). Complete resection of the MRI- and EEG-defined EZ is the best predictor of seizure freedom, though patients incomplete by EEG or MRI alone have better outcome compared to patients incomplete by both. More than one-third of patients with incomplete resection become SF, with contiguous MRI lesions a predictor of SF outcome.

What is the significance of a microscopically positive resection margin in the curative-intent treatment of rectal adenocarcinoma? A retrospective study.

PubMed

Fekete, Z; Muntean, A; Irimie, A; Hica, S; Resiga, L; Todor, N; Nagy, V

2013-01-01

The aim of this study was to analyze the characteristics of patients with rectal cancer operated with a microscopic positive margin (R1) and thus avoid these situations or adapt treatment in these particular cases. We reviewed all the pathology data of resected specimens from patients with rectal or recto-sigmoid cancer operated with curative intent at the Institute of Oncology "Prof. Dr. Ion Chiricuta" between 2000-2011 (763 patients in 12 years) and the pathology files of patients from other institutions referred for adjuvant treatment to our hospital (318 patients). We included patients with anterior resection, Hartmann's procedure and abdomino-perineal resection, but we excluded patients with local excision and patients with R2/R1 at first, but R0 after re-resection (56 patients). We have identified 31 patients with R1, but had to exclude one case from analysis because this patient was lost to follow-up. With surgery alone the local relapse (LR) was unavoidable. In the neoadjuvant chemoradiation (CRT) group 85.7% of the patients did not develop LR despite of R1. In the adjuvant CRT cohort 50% of the patients were LR-free at 2 years after conventional radiotherapy (p<0.01). Based on these results it is concluded that a clear resection margin is extremely important for the local control of rectal cancer, because it cannot be always compensated by adjuvant CRT. In R1 cases neoadjuvant CRT seems to offer better prognosis than adjuvant CRT. To avoid R1 and its consequences a good quality control of total mesorectal excision (TME) is needed and CRT should be done before and not after surgery. R1 after primary surgery needs to be compensated by re-resection if possible, otherwise probably high dose radiotherapy with chemotherapy is needed.

Could anterior papillary muscle partial necrosis explain early mitral valve repair failure?

PubMed

Pozzi, Matteo; Generali, Tommaso; Henaine, Roland; Mitchell, Julia; Lemaire, Anais; Chiari, Pascal; Fran, Jean; Obadia, Jean François

2014-09-01

Standardized techniques of mitral valve repair (MVR) have recently witnessed the introduction of a 'respect rather than resect' concept, the strategy of which involves the use of artificial chordae. MVR displays several advantages over mitral valve replacement in degenerative mitral regurgitation (MR), but the risk of reoperation for MVR failure must be taken into account. Different mechanisms could be advocated as the leading cause of MVR failure; procedure-related mechanisms are usually involved in early MVR failure, while valve-related mechanisms are common in late failure. Here, the case is reported of an early failure of MVR using artificial chordae that could be explained by an unusual procedure-related mechanism, namely anterior papillary muscle necrosis. MVR failure is a well-known complication after surgical repair of degenerative MR, but anterior papillary muscle partial necrosis might also be considered a possible mechanism of procedure-related MVR failure, especially when considering the increasing use of artificial chordae. Owing to the encouraging results obtained, mitral valve re-repair might be considered a viable solution, but must be selected after only a meticulous evaluation of the underlying mechanism of MVR failure.

Traceable low and ultra-low temperatures in The Netherlands

NASA Astrophysics Data System (ADS)

Peruzzi, A.; Bosch, W. A.

2009-02-01

The basis for worldwide uniformity of low and ultra-low temperature measurements is provided by two international temperature scales, the International Temperature Scale of 1990 (ITS-90) for temperatures above 0.65 K and the Provisional Low Temperature Scale of 2000 (PLTS-2000) for temperatures in the range 0.9 mK to 1 K. Over the past 10 years, the thermometry research in the Netherlands provided substantial contributions to the definition, realization and dissemination of these scales. We first give an overview of the Dutch contributions to the ITS-90 realization: a) 3He and 4He vapour pressure thermometer range of the ITS-90, 0.65 K to 4 K (1997), b) 4He interpolating constant volume gas thermometry for the ITS-90 range 3 K to 24.5 K (2007) and c) cryogenic fixed points for the ITS-90 range 13.8 K to 273.16 K (2005). Then we highlight our work on 3He melting pressure thermometry from 10 mK to 1 K (2003) to support the dissemination of the PLTS-2000. Finally we present the current status of the Dutch calibration facilities and dissemination devices providing for traceable low and ultra-low temperatures for use in science and industry: a) the NMi-VSL cryogenic calibration facility for the range 0.65 K to 273.16 K and b) the SRD1000 superconductive reference devices for the range 10 mK to 1 K.

Three-layer reconstruction for large defects of the anterior skull base.

PubMed

Sinha, Uttam K; Johnson, Terence E; Crockett, Dennis; Vadapalli, Satish; Gruen, Peter

2002-03-01

To evaluate and discuss a three-layer rigid reconstruction technique for large anterior skull base defects. Prospective, nonrandomized, non-blinded. Tertiary teaching medical center. Twenty consecutive patients underwent craniofacial resection for a variety of pathology. All patients had large anterior cranial base defects involving the cribriform plate, fovea ethmoidalis, and medial portion of the roof of the orbit at least on one side. A few patients had more extensive defects involving both roof of the orbits, planum sphenoidale, and bones of the upper third of the face. The defects were reconstructed with a three-layer technique. A watertight seal was obtained with a pericranial flap separating the neurocranium from the viscerocranium. Rigid support was provided by bone grafts fixed to a titanium mesh, anchored laterally to the orbital roofs. All patients had a computed tomography scan of the skull on the first or second postoperative day. Patients were observed for immediate and long-term postoperative complications after such reconstruction. Postoperative computed tomography scans showed small pneumocephalus in all patients. It resolved spontaneously and did not produce neurologic deficits in any patient. There was no cerebrospinal fluid leak, hematoma, or infection. On long-term follow-up, exposures of bone graft or mesh, brain herniation, or transmission of brain pulsation to the eyes were not observed in any patient. Three-layer reconstruction using bone grafts, titanium mesh, and pericranial flap provides an alternative technique for repair of large anterior cranial base defects. It is safe and effective, and provides rigid protection to the brain.

Robotic liver surgery: results for 70 resections.

PubMed

Giulianotti, Pier Cristoforo; Coratti, Andrea; Sbrana, Fabio; Addeo, Pietro; Bianco, Francesco Maria; Buchs, Nicolas Christian; Annechiarico, Mario; Benedetti, Enrico

2011-01-01

Robotic surgery is gaining popularity for digestive surgery; however, its use for liver surgery is reported scarcely. This article reviews a surgeon's experience with the use of robotic surgery for liver resections. From March 2002 to March 2009, 70 robotic liver resections were performed at 2 different centers by a single surgeon. The surgical procedure and postoperative outcome data were reviewed retrospectively. Malignant tumors were indications for resections in 42 (60%) patients, whereas benign tumors were indications in 28 (40%) patients. The median age was 60 years (range, 21-84) and 57% of patients were female. Major liver resections (≥ 3 liver segments) were performed in 27 (38.5%) patients. There were 4 conversions to open surgery (5.7%). The median operative time for a major resection was 313 min (range, 220-480) and 198 min (range, 90-459) for minor resection. The median blood loss was 150 mL (range, 20-1,800) for minor resection and 300 mL (range, 100-2,000) for major resection. The mortality rate was 0%, and the overall rate of complications was 21%. Major morbidity occurred in 4 patients in the major hepatectomies group (14.8%) and in 4 patients in the minor hepatectomies group (9.3%). All complications were managed conservatively and none required reoperation. This preliminary experience shows that robotic surgery can be used safely for liver resections with a limited conversion rate, blood loss, and postoperative morbidity. Robotics offers a new technical option for minimally invasive liver surgery. Copyright © 2011 Mosby, Inc. All rights reserved.

Effect of repeated passive anterior loading on human knee anterior laxity.

PubMed

Vauhnik, Renata; Perme, Maja Pohar; Barcellona, Massimo G; Morrissey, Matthew C; Sevšek, France; Rugelj, Darja

2015-10-01

Increased knee anterior laxity results when the anterior cruciate ligament is injured. This increased laxity can cause knee dysfunction. Until recently this laxity was believed to be only diminished through surgery. But recent findings indicate that knee anterior laxity may be decreased with repeated loading of the knee. The purpose of this study was to test the hypothesis that regular passive anterior loading of the uninjured human knee would enhance its stiffness. Randomized controlled trial. Knee anterior laxity was tested using an arthrometer in 22 young, uninjured females before, during and after a 3 month period during which passive anterior loading was applied by a trained physiotherapist over 5 sessions per week to a randomly assigned knee. Knee anterior laxity was not affected by the passive anterior loading of the knee. Given that in this study repeated passive loading of the knee did not change knee anterior laxity, it would be easy to conclude that this training is ineffective and no further research is required. We caution against this given the relatively short duration and possibly insufficient intensity of the training and the population studied; individuals with normal joint laxity. We recommend that future research be performed that consists of individuals with lax joints who receive training for prolonged periods. Copyright © 2015 Elsevier Ltd. All rights reserved.

Ultra-low magnetic field apparatus for a cryogenic gyroscope

NASA Technical Reports Server (NTRS)

Cabrera, B.; Van Kann, F. J.

1978-01-01

An ultralow magnetic field apparatus for earth-based testing of a cryogenic gyroscope system designed for a satellite test of general relativity is described. The magnetic field apparatus makes use of a superconducting lead shield while also maintaining sufficient mechanical stability to obtain a gyroscope readout sensitivity of one arcsec over a limited range. A gyroscope environment of 2.3 times 10 to the minus seventh power gauss has been attained with the magnetic field shielding technique. The magnetic field apparatus is to be used with a three-axis London moment readout system.

Robotic vascular resections during Whipple procedure.

PubMed

Allan, Bassan J; Novak, Stephanie M; Hogg, Melissa E; Zeh, Herbert J

2018-01-01

Indications for resection of pancreatic cancers have evolved to include selected patients with involvement of peri-pancreatic vascular structures. Open Whipple procedures have been the standard approach for patients requiring reconstruction of the portal vein (PV) or superior mesenteric vein (SMV). Recently, high-volume centers are performing minimally invasive Whipple procedures with portovenous resections. Our institution has performed seventy robotic Whipple procedures with concomitant vascular resections. This report outlines our technique.

Possible Mechanism of Action of the Electromagnetic Fields of Ultralow Frequency on G-protein

NASA Astrophysics Data System (ADS)

Nava, J. J. Godina; Segura, M. A. Rodríguez; García, M. N. Jiménez; Cadena, M. S. Reyes

2008-08-01

Based in several clinical achievements and mathematical simulation of the immune sytem, previously studied, permit us to establish that a possible Mechanism of Action of ultralow frequency Electromagnetic Fields (ELF) is on G-protein as it has been proposed in specialized literature.

Ultralow-Loss CMOS Copper Plasmonic Waveguides.

PubMed

Fedyanin, Dmitry Yu; Yakubovsky, Dmitry I; Kirtaev, Roman V; Volkov, Valentyn S

2016-01-13

Surface plasmon polaritons can give a unique opportunity to manipulate light at a scale well below the diffraction limit reducing the size of optical components down to that of nanoelectronic circuits. At the same time, plasmonics is mostly based on noble metals, which are not compatible with microelectronics manufacturing technologies. This prevents plasmonic components from integration with both silicon photonics and silicon microelectronics. Here, we demonstrate ultralow-loss copper plasmonic waveguides fabricated in a simple complementary metal-oxide semiconductor (CMOS) compatible process, which can outperform gold plasmonic waveguides simultaneously providing long (>40 μm) propagation length and deep subwavelength (∼λ(2)/50, where λ is the free-space wavelength) mode confinement in the telecommunication spectral range. These results create the backbone for the development of a CMOS plasmonic platform and its integration in future electronic chips.

Pancreatoduodenectomy with portal vein resection for distal cholangiocarcinoma.

PubMed

Maeta, T; Ebata, T; Hayashi, E; Kawahara, T; Mizuno, S; Matsumoto, N; Ohta, S; Nagino, M

2017-10-01

Little is known about the value of portal vein (PV) resection in distal cholangiocarcinoma. The aim of this study was to evaluate the clinical significance of PV resection in distal cholangiocarcinoma. Patients who underwent pancreatoduodenectomy (PD) for distal cholangiocarcinoma between 2001 and 2010 at one of 31 hospitals in Japan were reviewed retrospectively with special attention to PV resection. Short- and long-term outcomes were evaluated. In the study interval, 453 consecutive patients with distal cholangiocarcinoma underwent PD, of whom 31 (6·8 per cent) had combined PV resection. The duration of surgery (510 versus 427 min; P = 0·005) and incidence of blood transfusion (48 versus 30·7 per cent; P = 0·042) were greater in patients who had PV resection than in those who did not. Postoperative morbidity and mortality were no different in the two groups. Several indices of tumour progression, including high T classification, lymphatic invasion, perineural invasion, pancreatic invasion and lymph node metastasis, were more common in patients who had PV resection. Consequently, the incidence of R1/2 resection was higher in this group (32 versus 11·8 per cent; P = 0·004). Survival among the 31 patients with PV resection was worse than that for the 422 patients without PV resection (15 versus 42·4 per cent at 5 years; P < 0·001). Multivariable analyses revealed that age, blood loss, histological grade, perineural invasion, pancreatic invasion, lymph node metastasis and surgical margin were independent risk factors for overall survival. PV resection was not an independent risk factor. PV invasion in distal cholangiocarcinoma is associated with locally advanced disease and several negative prognostic factors. Survival for patients who have PV resection is poor even after curative resection. © 2017 BJS Society Ltd Published by John Wiley & Sons Ltd.

Spatial and contrast resolution of ultralow dose dentomaxillofacial CT imaging using iterative reconstruction technology

PubMed Central

Bischel, Alexander; Stratis, Andreas; Bosmans, Hilde; Jacobs, Reinhilde; Gassner, Eva-Maria; Puelacher, Wolfgang; Pauwels, Ruben

2017-01-01

Objectives: The objective of this study was to determine how iterative reconstruction technology (IRT) influences contrast and spatial resolution in ultralow-dose dentomaxillofacial CT imaging. Methods: A polymethyl methacrylate phantom with various inserts was scanned using a reference protocol (RP) at CT dose index volume 36.56 mGy, a sinus protocol at 18.28 mGy and ultralow-dose protocols (LD) at 4.17 mGy, 2.36 mGy, 0.99 mGy and 0.53 mGy. All data sets were reconstructed using filtered back projection (FBP) and the following IRTs: adaptive statistical iterative reconstructions (ASIRs) (ASIR-50, ASIR-100) and model-based iterative reconstruction (MBIR). Inserts containing line-pair patterns and contrast detail patterns for three different materials were scored by three observers. Observer agreement was analyzed using Cohen's kappa and difference in performance between the protocols and reconstruction was analyzed with Dunn's test at α = 0.05. Results: Interobserver agreement was acceptable with a mean kappa value of 0.59. Compared with the RP using FBP, similar scores were achieved at 2.36 mGy using MBIR. MIBR reconstructions showed the highest noise suppression as well as good contrast even at the lowest doses. Overall, ASIR reconstructions did not outperform FBP. Conclusions: LD and MBIR at a dose reduction of >90% may show no significant differences in spatial and contrast resolution compared with an RP and FBP. Ultralow-dose CT and IRT should be further explored in clinical studies. PMID:28059562

Augmented reality in bone tumour resection: An experimental study.

PubMed

Cho, H S; Park, Y K; Gupta, S; Yoon, C; Han, I; Kim, H-S; Choi, H; Hong, J

2017-03-01

We evaluated the accuracy of augmented reality (AR)-based navigation assistance through simulation of bone tumours in a pig femur model. We developed an AR-based navigation system for bone tumour resection, which could be used on a tablet PC. To simulate a bone tumour in the pig femur, a cortical window was made in the diaphysis and bone cement was inserted. A total of 133 pig femurs were used and tumour resection was simulated with AR-assisted resection (164 resection in 82 femurs, half by an orthropaedic oncology expert and half by an orthopaedic resident) and resection with the conventional method (82 resection in 41 femurs). In the conventional group, resection was performed after measuring the distance from the edge of the condyle to the expected resection margin with a ruler as per routine clinical practice. The mean error of 164 resections in 82 femurs in the AR group was 1.71 mm (0 to 6). The mean error of 82 resections in 41 femurs in the conventional resection group was 2.64 mm (0 to 11) (p < 0.05, one-way analysis of variance). The probabilities of a surgeon obtaining a 10 mm surgical margin with a 3 mm tolerance were 90.2% in AR-assisted resections, and 70.7% in conventional resections. We demonstrated that the accuracy of tumour resection was satisfactory with the help of the AR navigation system, with the tumour shown as a virtual template. In addition, this concept made the navigation system simple and available without additional cost or time. Cite this article: H. S. Cho, Y. K. Park, S. Gupta, C. Yoon, I. Han, H-S. Kim, H. Choi, J. Hong. Augmented reality in bone tumour resection: An experimental study. Bone Joint Res 2017;6:137-143. © 2017 Cho et al.

Local resection of the stomach for gastric cancer.

PubMed

Kinami, Shinichi; Funaki, Hiroshi; Fujita, Hideto; Nakano, Yasuharu; Ueda, Nobuhiko; Kosaka, Takeo

2017-06-01

The local resection of the stomach is an ideal method for preventing postoperative symptoms. There are various procedures for performing local resection, such as the laparoscopic lesion lifting method, non-touch lesion lifting method, endoscopic full-thickness resection, and laparoscopic endoscopic cooperative surgery. After the invention and widespread use of endoscopic submucosal dissection, local resection has become outdated as a curative surgical technique for gastric cancer. Nevertheless, local resection of the stomach in the treatment of gastric cancer in now expected to make a comeback with the clinical use of sentinel node navigation surgery. However, there are many issues associated with local resection for gastric cancer, other than the normal indications. These include gastric deformation, functional impairment, ensuring a safe surgical margin, the possibility of inducing peritoneal dissemination, and the associated increase in the risk of metachronous gastric cancer. In view of these issues, there is a tendency to regard local resection as an investigative treatment, to be applied only in carefully selected cases. The ideal model for local resection of the stomach for gastric cancer would be a combination of endoscopic full-thickness resection of the stomach using an ESD device and hand sutured closure using a laparoscope or a surgical robot, for achieving both oncological safety and preserved functions.

Ultralow frequency MHD waves in Jupiter's middle magnetosphere

NASA Technical Reports Server (NTRS)

Khurana, Krishan K.; Kivelson, Margaret G.

1989-01-01

Ultralow frequency (ULF) magnetohydrodynamic pulsations (periods between 10 and 20 min) were observed on July 8-11, 1979 as Voyager 2 traveled through the middle magnetosphere of Jupiter between radial distances of 10 R(J) and 35 R(J). The particle and magnetic pressure perturbations associated with the waves were anticorrelated. The electron and ion perturbations on the dayside were in phase. The pressure perturbations occurred both within and outside of the plasma sheet. Perturbations in the transverse components of the magnetic field were associated with the compressional perturbations but the transverse power peaked within the plasma sheet of Jupiter and diminished rapidly outside of it.

Microfluidic ultralow interfacial tensiometry with magnetic particles.

PubMed

Tsai, Scott S H; Wexler, Jason S; Wan, Jiandi; Stone, Howard A

2013-01-07

We describe a technique that measures ultralow interfacial tensions using paramagnetic spheres in a co-flow microfluidic device designed with a magnetic section. Our method involves tuning the distance between the co-flowing interface and the magnet's center, and observing the behavior of the spheres as they approach the liquid-liquid interface-the particles either pass through or are trapped by the interface. Using threshold values of the magnet-to-interface distance, we make estimates of the two-fluid interfacial tension. We demonstrate the effectiveness of this technique for measuring very low interfacial tensions, O(10(-6)-10(-5)) N m(-1), by testing solutions of different surfactant concentrations, and we show that our results are comparable with measurements made using a spinning drop tensiometer.

Comparison of Laparoscopic Discoid Resection and Segmental Resection for Colorectal Endometriosis Using a Propensity Score Matching Analysis.

PubMed

Jayot, Aude; Nyangoh Timoh, Krystel; Bendifallah, Sofiane; Ballester, Marcos; Darai, Emile

Our primary endpoint was to compare the intra- and postoperative complications, whereas secondary endpoints were the occurrence of voiding dysfunction and evaluation of the quality or life of segmental and discoid resection in patients with colorectal endometriosis. Retrospective study (Canadian Task Force classification II-2). Tenon University Hospital in Paris. Thirty-one 31 patients who underwent a conservative surgery and 31 patients who underwent. The 2 groups were compared using propensity score matching (PSM) analysis, with a median follow-up of 247 days (8.2 months). Discoid colorectal resection was associated with a shorter operating time (155 vs 180 minutes, p = .03) and hospital stay (7 vs 8 days, p = .002) than segmental colorectal resection; however, a similar intra- and postoperative complication rate was found. A higher rate of postoperative voiding dysfunction was observed in the segmental resection group (19% vs 45%, p = .03) as well as duration of voiding dysfunction requiring bladder self-catheterization longer than 30 days (0 vs 22%, p = .005). Our PSM analysis suggests the advantages of discoid resection because it results in a similar surgical complication rate to segmental resection but with advantages in operating time, hospital stay, and voiding dysfunction. Copyright © 2017 American Association of Gynecologic Laparoscopists. Published by Elsevier Inc. All rights reserved.

[Laparoscopic resection of stomach in case of stomach ulcer].

PubMed

Sazhin, I V; Sazhin, V P; Nuzhdikhin, A V

2014-01-01

Laparoscopic resection of stomach was done in 84 patients with complicated peptic ulcer of stomach and duodenum. There were 1.2% post-operative complications in case of laparoscopic resection of stomach in comparison with open resection, which had 33.3% complications. There were not deaths in case of laparoscopic resection of stomach. This indication was about 4% in patients after open resection. It was determined that functionalefficiency afterlaparoscopic resection was in 1.6-1.8 times higher than afteropen resectionof stomach.

Circumferential resection margin (CRM) positivity after MRI assessment and adjuvant treatment in 189 patients undergoing rectal cancer resection.

PubMed

Simpson, G S; Eardley, N; McNicol, F; Healey, P; Hughes, M; Rooney, P S

2014-05-01

The management of rectal cancer relies on accurate MRI staging. Multi-modal treatments can downstage rectal cancer prior to surgery and may have an effect on MRI accuracy. We aim to correlate the findings of MRI staging of rectal cancer with histological analysis, the effect of neoadjuvant therapy on this and the implications of circumferential resection margin (CRM) positivity following neoadjuvant therapy. An analysis of histological data and radiological staging of all cases of rectal cancer in a single centre between 2006 and 2011 were conducted. Two hundred forty-one patients had histologically proved rectal cancer during the study period. One hundred eighty-two patients underwent resection. Median age was 66.6 years, and male to female ratio was 13:5. R1 resection rate was 11.1%. MRI assessments of the circumferential resection margin in patients without neoadjuvant radiotherapy were 93.6 and 88.1% in patients who underwent neoadjuvant radiotherapy. Eighteen patients had predicted positive margins following chemoradiotherapy, of which 38.9% had an involved CRM on histological analysis. MRI assessment of the circumferential resection margin in rectal cancer is associated with high accuracy. Neoadjuvant chemoradiotherapy has a detrimental effect on this accuracy, although accuracy remains high. In the presence of persistently predicted positive margins, complete resection remains achievable but may necessitate a more radical approach to resection.

Rotatable Small Permanent Magnet Array for Ultra-Low Field Nuclear Magnetic Resonance Instrumentation: A Concept Study

PubMed Central

Vegh, Viktor; Reutens, David C.

2016-01-01

Object We studied the feasibility of generating the variable magnetic fields required for ultra-low field nuclear magnetic resonance relaxometry with dynamically adjustable permanent magnets. Our motivation was to substitute traditional electromagnets by distributed permanent magnets, increasing system portability. Materials and Methods The finite element method (COMSOL®) was employed for the numerical study of a small permanent magnet array to calculate achievable magnetic field strength, homogeneity, switching time and magnetic forces. A manually operated prototype was simulated and constructed to validate the numerical approach and to verify the generated magnetic field. Results A concentric small permanent magnet array can be used to generate strong sample pre-polarisation and variable measurement fields for ultra-low field relaxometry via simple prescribed magnet rotations. Using the array, it is possible to achieve a pre-polarisation field strength above 100 mT and variable measurement fields ranging from 20–50 μT with 200 ppm absolute field homogeneity within a field-of-view of 5 x 5 x 5 cubic centimetres. Conclusions A dynamic small permanent magnet array can generate multiple highly homogeneous magnetic fields required in ultra-low field nuclear magnetic resonance (NMR) and magnetic resonance imaging (MRI) instruments. This design can significantly reduce the volume and energy requirements of traditional systems based on electromagnets, improving portability considerably. PMID:27271886

Multifunctional Hybrid Multilayer Gate Dielectrics with Tunable Surface Energy for Ultralow-Power Organic and Amorphous Oxide Thin-Film Transistors.

PubMed

Byun, Hye-Ran; You, Eun-Ah; Ha, Young-Geun

2017-03-01

For large-area, printable, and flexible electronic applications using advanced semiconductors, novel dielectric materials with excellent capacitance, insulating property, thermal stability, and mechanical flexibility need to be developed to achieve high-performance, ultralow-voltage operation of thin-film transistors (TFTs). In this work, we first report on the facile fabrication of multifunctional hybrid multilayer gate dielectrics with tunable surface energy via a low-temperature solution-process to produce ultralow-voltage organic and amorphous oxide TFTs. The hybrid multilayer dielectric materials are constructed by iteratively stacking bifunctional phosphonic acid-based self-assembled monolayers combined with ultrathin high-k oxide layers. The nanoscopic thickness-controllable hybrid dielectrics exhibit the superior capacitance (up to 970 nF/cm 2 ), insulating property (leakage current densities <10 -7 A/cm 2 ), and thermal stability (up to 300 °C) as well as smooth surfaces (root-mean-square roughness <0.35 nm). In addition, the surface energy of the hybrid multilayer dielectrics are easily changed by switching between mono- and bifunctional phosphonic acid-based self-assembled monolayers for compatible fabrication with both organic and amorphous oxide semiconductors. Consequently, the hybrid multilayer dielectrics integrated into TFTs reveal their excellent dielectric functions to achieve high-performance, ultralow-voltage operation (< ± 2 V) for both organic and amorphous oxide TFTs. Because of the easily tunable surface energy, the multifunctional hybrid multilayer dielectrics can also be adapted for various organic and inorganic semiconductors, and metal gates in other device configurations, thus allowing diverse advanced electronic applications including ultralow-power and large-area electronic devices.

Technical aspects of virtual liver resection planning.

PubMed

Glombitza, G; Lamadé, W; Demiris, A M; Göpfert, M R; Mayer, A; Bahner, M L; Meinzer, H P; Richter, G; Lehnert, T; Herfarth, C

1998-01-01

Operability of a liver tumor is depending on its three dimensional relation to the intrahepatic vascular trees which define autonomously functioning liver (sub-)segments. Precise operation planning is complicated by anatomic variability, distortion of the vascular trees by the tumor or preceding liver resections. Because of the missing possibility to track the deformation of the liver during the operation an integration of the resection planning system into an intra-operative navigation system is not feasible. So the main task of an operation planning system in this domain is a quantifiable patient selection by exact prediction of post-operative liver function and a quantifiable resection proposal. The system quantifies the organ structures and resection volumes by means of absolute and relative values. It defines resection planes depending on security margins and the vascular trees and presents the data in visualized form as a 3D movie. The new 3D operation planning system offers quantifiable liver resection proposals based on individualized liver anatomy. The results are visualized in digital movies as well as in quantitative reports.

Tricuspid leaflet resection in an open beating heart for the creation of a canine tricuspid regurgitation model.

PubMed

Xie, Xu-jing; Liao, Sheng-jie; Wu, Yue-heng; Lu, Cong; Zhu, Ping; Fei, Hong-wen; Xiao, Xue-jun; Huang, Huan-lei

2016-02-01

Outcomes of tricuspid valve replacement are poor, partly due to right heart remodelling. The research on its underlying mechanisms is hampered by a lack of animal models of tricuspid regurgitation (TR). Our objective was to create a reproducible and clinically compatible TR animal model to study right heart remodelling caused by TR. Fourteen juvenile male Beagle dogs were divided randomly into an intervention group (n = 11) and a sham-operated control group (n = 3). The intervention group underwent thoracotomy and right atrial incision following superior and inferior vena caval occlusion. The anterior leaflet, together with the chordae, of the tricuspid valve was resected in eight dogs ('one leaflet' group), whereas both anterior and posterior leaflets, together with the chordae, were resected in three dogs ('two leaflets' group). The right atrium and chest were then closed. The control group underwent the same procedure, except leaflet resection. One dog from the 'two leaflets' group and one control dog were sacrificed and autopsy was performed at 12 months post-surgery. All dogs survived over the 1-year observation period postoperatively. TR grade IV occurred immediately postoperatively in the 'one leaflet' group, and TR grade IV plus in the 'two leaflets' group. The overall procedure lasted 30-40 min, and the mean time of vena caval occlusion was 87 ± 10 s. Central venous pressure increased from 6 ± 1.2 at baseline to 13 ± 1.7 mmHg (P < 0.01). By 12 months after TR creation, both in the 'one leaflet' group and in the 'two leaflets' group, the right atrial area, tricuspid annular diameter and right ventricular index of myocardial performance increased significantly, right ventricular fractional area change and tricuspid annular plane systolic excursion decreased significantly. Autopsy of the intervention dog revealed oedema, ascites and cirrhosis. Our surgical technique to create a TR animal model was reproducible with high success and survival rates. This

A low-cost, ultra-fast and ultra-low noise preamplifier for silicon avalanche photodiodes

NASA Astrophysics Data System (ADS)

Gasmi, Khaled

2018-02-01

An ultra-fast and ultra-low noise preamplifier for amplifying the fast and weak electrical signals generated by silicon avalanche photodiodes has been designed and developed. It is characterized by its simplicity, compactness, reliability and low cost of construction. A very wide bandwidth of 300 MHz, a very good linearity from 1 kHz to 280 MHz, an ultra-low noise level at the input of only 1.7 nV Hz-1/2 and a very good stability are its key features. The compact size (70 mm  ×  90 mm) and light weight (45 g), as well as its excellent characteristics, make this preamplifier very competitive compared to any commercial preamplifier. The preamplifier, which is a main part of the detection system of a homemade laser remote sensing system, has been successfully tested. In addition, it is versatile and can be used in any optical detection system requiring high speed and very low noise electronics.

The Effect of Ultralow-Dose Transdermal Estradiol on Urinary Incontinence in Postmenopausal Women

PubMed Central

Waetjen, L. Elaine; Brown, Jeanette S.; Vittinghoff, Eric; Ensrud, Kristine E.; Pinkerton, JoAnn; Wallace, Robert; Macer, Judith L.; Grady, Deborah

2006-01-01

OBJECTIVE To estimate the effect of 2 years of treatment with ultralow-dose transdermal estradiol (E2) on incontinence in postmenopausal women. METHODS Ultra Low Dose Transdermal estRogen Assessment (ULTRA) was a multicenter, randomized, double-blinded, placebo-controlled trial of unopposed ultralow-dose (0.014 mg/d) transdermal E2 for prevention of osteoporosis in 417 postmenopausal women aged 60 to 80 years. Frequency of incontinence episodes was assessed at baseline and after 4 months and 2 years of treatment using a self-reported questionnaire. We used an intention-to-treat analysis to compare change in incontinence frequency, improved (decreased 2 or more episodes per week), unchanged (increased or decreased no more than 1 episode per week), or worsened (increased 2 or more episodes per week) between the E2 and placebo groups among women with and without at least weekly incontinence at baseline. RESULTS At baseline, the prevalence of at least weekly incontinence was similar between E2 and placebo groups (43%). After 2 years, there was no difference between groups in the proportions of women with incontinence at baseline whose incontinence improved, worsened, or was unchanged. The odds ratio for worsening incontinence in the E2 compared with placebo group was 1.35 (95% confidence interval 0.75–2.42. In women without incontinence at baseline, the odds of developing at least weekly incontinence after 2 years in the E2 compared with placebo group was not significant (odds ratio 1.2, 95% confidence interval 0.7–2.2). CONCLUSION Two years of treatment with unopposed ultralow-dose transdermal E2 did not substantially change the frequency of incontinence symptoms or alter the risk of developing at least weekly incontinence. PMID:16260511

Potentiation of buprenorphine antinociception with ultra-low dose naltrexone in healthy subjects.

PubMed

Hay, J L; La Vincente, S F; Somogyi, A A; Chapleo, C B; White, J M

2011-03-01

Previous reports have demonstrated greater antinociception following administration of a buprenorphine/naloxone combination compared to buprenorphine alone among healthy volunteers. The aim of the current investigation was to determine whether buprenorphine antinociception could be enhanced with the addition of ultra-low dose naltrexone, using a range of dose ratios. A repeated-measures, double-blind, cross-over trial was undertaken with 10 healthy participants. The effects of each buprenorphine:naltrexone ratio (100:1, 133:1, 166:1, and 200:1) on cold pressor tolerance time and respiration were compared to the effects of buprenorphine only. The 166:1 ratio was associated with significantly greater tolerance time to cold pressor pain than buprenorphine alone. Minimal respiratory depression and few adverse events were observed in all conditions. These findings suggest that, as previously described with naloxone, the addition of ultra-low dose naltrexone can enhance the antinociceptive effect of buprenorphine in humans. This potentiation is dose-ratio dependent and occurs without a concomitant increase in adverse effects. Copyright © 2010 European Federation of International Association for the Study of Pain Chapters. Published by Elsevier Ltd. All rights reserved.

Transurethral resection of the prostate - discharge

MedlinePlus

... men report a lower amount of semen during orgasm after having TURP. Urinary Catheters You may feel ... More Enlarged prostate Prostate resection - minimally invasive Retrograde ejaculation Simple prostatectomy Transurethral resection of the prostate Urinary ...

Evaluation of an Ultra-Low Power Reed Solomon Encoder for NASA's Space Technology 5 Mission

NASA Technical Reports Server (NTRS)

Li, K. E.; Xapsos, M. A.; Poivey, C.; LaBel, K. A.; Stone, R. F.; Yeh, P-S.; Gambles, J.; Hass, J.; Maki, G.; Marguia, J.

2003-01-01

This viewgraph presentation provides information on radiation tests on encoders intended for a constellation of microsatellites. The encoders use CMOS Ultra-Low Power Radiation Tolerant (CULPRiT) technology. The presentation addresses power consumption, radiation dosage, and Single Event Upset (SEU).

A Study of Submicron Grain Boundary Precipitates in Ultralow Carbon 316LN Steels

NASA Astrophysics Data System (ADS)

Downey, S.; Han, K.; Kalu, P. N.; Yang, K.; Du, Z. M.

2010-04-01

This article reports our efforts in characterization of an ultralow carbon 316LN-type stainless steel. The carbon content in the material is one-third that in a conventional 316LN, which further inhibits the formation of grain boundary carbides and therefore sensitizations. Our primary effort is focused on characterization of submicron size precipitates in the materials with the electron backscatter diffraction (EBSD) technique complemented by Auger electron spectroscopy (AES). Thermodynamic calculations suggested that several precipitates, such as M23C6, Chi, Sigma, and Cr2N, can form in a low carbon 316LN. In the steels heat treated at 973 K (700 °C) for 100 hours, a combination of EBSD and AES conclusively identified the grain boundary precipitates (≥100 nm) as Cr2N, which has a hexagonal closed-packed crystallographic structure. Increases of the nitrogen content promote formation of large size Cr2N precipitates. Therefore, prolonged heat treatment at relatively high temperatures of ultralow carbon 316LN steels may result in a sensitization.

[Robot-assisted liver resection].

PubMed

Aselmann, H; Möller, T; Kersebaum, J-N; Egberts, J H; Croner, R; Brunner, M; Grützmann, R; Becker, T

2017-06-01

Robotic liver resection can overcome some of the limitations of laparoscopic liver surgery; therefore, it is a promising tool to increase the proportion of minimally invasive liver resections. The present article gives an overview of the current literature. Furthermore, the results of a nationwide survey on robotic liver surgery among hospitals in Germany with a DaVinci system used in general visceral surgery and the perioperative results of two German robotic centers are presented.

Stimulation of the bilateral anterior nuclei of the thalamus in the treatment of refractory epilepsy: two cases of subcortical band heterotopia.

PubMed

Franco, Ana; Pimentel, José; Campos, Alexandre Rainha; Morgado, Carlos; Pinelo, Sara; Ferreira, António Gonçalves; Bentes, Carla

2016-12-01

Subcortical band heterotopia is a neuronal migration disorder that may cause refractory epilepsy. In these patients, resective surgery has yielded inadequate results. Deep brain stimulation of the anterior nuclei of the thalamus has been used for the treatment of refractory epilepsy with good results. We describe the first two patients with subcortical band heterotopia who were submitted to deep brain stimulation of the anterior nuclei of the thalamus, with evaluation of seizure outcome after 12 and 18 months of follow-up. At these times, both showed a >50% decrease in seizure frequency and an increase in seizure freedom. Both patients had a depressive syndrome after surgery that responded fully to anti-depressive medication in one patient and partly in the other. In both, deep brain stimulation of the anterior nuclei of the thalamus was associated with good seizure outcome. This procedure can therefore be considered in the treatment of patients with subcortical band heterotopia and refractory epilepsy. Depression may be a transient adverse event of the surgery or stimulation, however, its aetiology is probably multifactorial.

Klatskin tumour: meticulous preoperative work-up and resection rate.

PubMed

Otto, G; Hoppe-Lotichius, M; Bittinger, F; Schuchmann, M; Düber, C

2011-04-01

Surgery represents the only potentially curative treatment of hilar cholangiocarcinoma (hilCC). It may be suggested that meticulous preoperative work-up in Asian countries leads to higher resection rates. One hundred and eighty-two patients treated in our department between 1998 and 2008 were included in an analysis based on our prospectively recorded database. Among them, 75 % had a percutaneous transhepatic cholangiography as part of their diagnostic work-up. A total of 160 patients underwent explorative surgery and 123 patients were resected (77 % of patients undergoing exploration, 68 % of all patients). Ninety-one percent of the patients were diagnosed to have Bismuth III and IV tumours. En-bloc resection of the tumour and the adjacent liver including segment 1 was the standard procedure in 109 of these patients, while hilar resection was performed in 14 patients. Upon tumour resection, hospital mortality was 5.7 %. Five-year survival in patients without surgery or with mere exploration was 0 %, after resection it reached 26 %. Patients with R 1 resection experienced longer survival than patients without resection (p < 0.001). Right and left hemihepatectomies were performed with identical frequency resulting in identical survival. Lymph node involvement proved to be the only significant predictor of prognosis (p = 0.006). Resection should be performed whenever possible since even after palliative resection survival is substantially increased compared to patients without resection. Meticulous preoperative work-up may contribute to a high resection rate in patients with hilCC by providing additional information allowing the surgeon to perform more aggressive approaches. © Georg Thieme Verlag KG Stuttgart · New York.

Laparoscopic resection of hilar cholangiocarcinoma.

PubMed

Lee, Woohyung; Han, Ho-Seong; Yoon, Yoo-Seok; Cho, Jai Young; Choi, YoungRok; Shin, Hong Kyung; Jang, Jae Yool; Choi, Hanlim

2015-10-01

Laparoscopic resection of hilar cholangiocarcinoma is technically challenging because it involves complicated laparoscopic procedures that include laparoscopic hepatoduodenal lymphadenectomy, hemihepatectomy with caudate lobectomy, and hepaticojejunostomy. There are currently very few reports describing this type of surgery. Between August 2014 and December 2014, 5 patients underwent total laparoscopic or laparoscopic-assisted surgery for hilar cholangiocarcinoma. Two patients with type I or II hilar cholangiocarcinoma underwent radical hilar resection. Three patients with type IIIa or IIIb cholangiocarcinoma underwent extended hemihepatectomy together with caudate lobectomy. The median (range) age, operation time, blood loss, and length of hospital stay were 63 years (43-76 years), 610 minutes (410-665 minutes), 650 mL (450-1,300 mL), and 12 days (9-21 days), respectively. Four patients had a negative margin, but 1 patient was diagnosed with high-grade dysplasia on the proximal resection margin. The median tumor size was 3.0 cm. One patient experienced postoperative biliary leakage, which resolved spontaneously. Laparoscopic resection is a feasible surgical approach in selected patients with hilar cholangiocarcinoma.

Ultralow-intensity magneto-optical and mechanical effects in metal nanocolloids.

PubMed

Moocarme, M; Domínguez-Juárez, J L; Vuong, L T

2014-03-12

Magneto-plasmonics is a designation generally associated with ferromagnetic-plasmonic materials because such optical responses from nonmagnetic materials alone are considered weak. Here, we show that there exists a switching transition between linear and nonlinear magneto-optical behaviors in noble-metal nanocolloids that is observable at ultralow illumination intensities and direct current magnetic fields. The response is attributed to polarization-dependent nonzero-time-averaged plasmonic loops, vortex power flows, and nanoparticle magnetization. This work identifies significant mechanical effects that subsequently exist via magnetic-dipole interactions.

Endoscopic full-thickness resection: Current status

PubMed Central

Schmidt, Arthur; Meier, Benjamin; Caca, Karel

2015-01-01

Conventional endoscopic resection techniques such as endoscopic mucosal resection or endoscopic submucosal dissection are powerful tools for treatment of gastrointestinal neoplasms. However, those techniques are restricted to superficial layers of the gastrointestinal wall. Endoscopic full-thickness resection (EFTR) is an evolving technique, which is just about to enter clinical routine. It is not only a powerful tool for diagnostic tissue acquisition but also has the potential to spare surgical therapy in selected patients. This review will give an overview about current EFTR techniques and devices. PMID:26309354

Endoscopic full-thickness resection: Current status.

PubMed

Schmidt, Arthur; Meier, Benjamin; Caca, Karel

2015-08-21

Conventional endoscopic resection techniques such as endoscopic mucosal resection or endoscopic submucosal dissection are powerful tools for treatment of gastrointestinal neoplasms. However, those techniques are restricted to superficial layers of the gastrointestinal wall. Endoscopic full-thickness resection (EFTR) is an evolving technique, which is just about to enter clinical routine. It is not only a powerful tool for diagnostic tissue acquisition but also has the potential to spare surgical therapy in selected patients. This review will give an overview about current EFTR techniques and devices.

Specific gravity and API gravity of biodiesel and ultra-low sulfur diesel (ULSD) blends

USDA-ARS?s Scientific Manuscript database

Biodiesel is an alternative fuel made from vegetable oils and animal fats. In 2006, the U. S. Environmental Protection Agency mandated a maximum sulfur content of 15 ppm in on-road diesel fuels. Processing to produce the new ultra-low sulfur petrodiesel (ULSD) alters specific gravity (SG) and othe...

Laparoscopic resection for diverticular disease.

PubMed

Bruce, C J; Coller, J A; Murray, J J; Schoetz, D J; Roberts, P L; Rusin, L C

1996-10-01

The role of laparoscopic surgery in treatment of patients with diverticulitis is unclear. A retrospective comparison of laparoscopic with conventional surgery for patients with chronic diverticulitis was performed to assess morbidity, recovery from surgery, and cost. Records of patients undergoing elective resection for uncomplicated diverticulitis from 1992 to 1994 at a single institution were reviewed. Laparoscopic resection involved complete intracorporeal dissection, bowel division, and anastomosis with extracorporeal placement of an anvil. Sigmoid and left colon resections were performed laparoscopically in 25 patients and by open technique in 17 patients by two independent operating teams. No significant differences existed in age, gender, weight, comorbidities, or operations performed. In the laparoscopic group, three operations were converted to open laparotomy (12 percent) because of unclear anatomy. Major complications occurred in two patients who underwent laparoscopic resection, both requiring laparotomy, and in one patient in the conventional surgery group who underwent computed tomographic-guided drainage of an abscess. Patients who underwent laparoscopic resection tolerated a regular diet sooner than patients who underwent conventional surgery (3.2 +/- 0.9 vs. 5.7 +/- 1.1 days; P < 0.001) and were discharged from the hospital earlier (4.2 +/- 1.1 vs. 6.8 +/- 1.1 days; P < 0.001). Overall costs were higher in the laparoscopic group than the open surgery group ($10,230 +/- 49.1 vs. $7,068 +/- 37.1; P < 0.001) because of a significantly longer total operating room time (397 +/- 9.1 vs. 115 +/- 5.1 min; P < 0.001). Follow-up studies with a mean of one year revealed two port site infections in the laparoscopic group and one wound infection in the open group. Of patients undergoing conventional resection, one patient experienced a postoperative bowel obstruction that was managed nonoperatively, and, in one patient, an incarcerated incisional hernia

Ultra-low profile Ovation device: is it the definitive solution for EVAR?

PubMed

de Donato, G; Setacci, F; Sirignano, P; Galzerano, G; Borrelli, M P; di Marzo, L; Setacci, C

2014-02-01

When Juan Parodi implanted an endograft in a human body for the first time on September 7, 1990 in Buenos Aires, Argentina, the delivery system of the handmade device was primitive, extremely rigid, and had a bulky profile of 27 French (F). Since then, stent-graft technology has evolved rapidly, limitations of earlier-generation devices have been overtaken, and endovascular aneurysm repair (EVAR) eligibility has increased enormously. Nevertheless (still) challenging aortoiliac anatomy such as short and complex proximal aortic neck seal zones and narrow access vessels are responsible for EVAR ineligibility in up to 50% of cases. The Ovation Prime abdominal stent-graft system (TriVascular, Inc., Santa Rosa, CA, USA) is a trimodular device designed with the aortic body delivered via a flexible, hydrophilic-coated, ultra-low profile catheter (14-F outer diameter - OD). The aortic body is provided with a suprarenal nitinol stent with anchors that provide active fixation, while a network of rings and channels that are inflated with a low-viscosity radiopaque polymer during stent-graft deployment, provides effective sealing. The previous EVAR technology aimed to both anchor and seal using stents combined with fabric, with neither optimized for their roles and each forced to compete for the same space within their delivery catheters, which inevitably led to larger profile of the delivery system. The technical revolution of the Ovation endograft includes the idea to truly uncouple the stages of stent-graft fixation and seal during the procedure. In the Ovation endograft platform, stent and fabric are not competing the same space within the delivery system and an ultra-low profile delivery can be achieved without compromise. With such a low-profile delivery catheter, approximately 90% of men and 70% of women with abdominal aortic aneurysm have access vessel diameters considered fit for endovascular repair. The aim of this review paper was to analyze the main properties of

Is Survival for Patients with Resectable Lung Metastatic Colorectal Cancer Comparable to Those with Resectable Liver Disease? Results from the South Australian Metastatic Colorectal Registry.

PubMed

Patel, Dainik; Townsend, Amanda R; Karapetis, Christos; Beeke, Carol; Padbury, Rob; Roy, Amitesh; Maddern, Guy; Roder, David; Price, Timothy J

2016-10-01

Hepatic resection for colorectal (CRC) metastasis is considered a standard of care. Resection of metastasis isolated to lung also is considered potentially curable, although there is still some variation in recommendations. We explore outcomes for patients undergoing lung resection for mCRC, with the liver resection group as the comparator. South Australian (SA) metastatic CRC registry data were analysed to assess patient characteristics and survival outcomes for patients suitable for lung or liver resection. A total of 3241 patients are registered on the database to December 2014. One hundred two (3.1 %) patients were able to undergo a lung resection compared with 420 (12.9 %) who had a liver resection. Of the lung resection patients, 62 (61 %) presented with lung disease only, 21 % initially presented with liver disease only, 11 % had both lung and liver, and 7 % had brain or pelvic disease resection. Of these patients, 79 % went straight to surgery without any neoadjuvant treatment and 34 % had lung resection as the only intervention. Chemotherapy for metastatic disease was given more often to liver resection patients: 76.9 versus 53.9 %, p = 0.17. Median overall survival is 5.6 years for liver resection and has not been reached for lung resection (hazard ratio 0.82, 95 % confidence interval 0.54-1.24, p = 0.33). Lung resection was undertaken in 3.1 % of patients with mCRC in our registry. These data provide further support for long-term survival after lung resection in mCRC, survival that is at least comparable to those who undergo resection for liver metastasis in mCRC.

Endoscopic endonasal double flap technique for reconstruction of large anterior skull base defects: technical note.

PubMed

Dolci, Ricardo Landini Lutaif; Todeschini, Alexandre Bossi; Santos, Américo Rubens Leite Dos; Lazarini, Paulo Roberto

2018-04-19

One of the main concerns in endoscopic endonasal approaches to the skull base has been the high incidence and morbidity associated with cerebrospinal fluid leaks. The introduction and routine use of vascularized flaps allowed a marked decrease in this complication followed by a great expansion in the indications and techniques used in endoscopic endonasal approaches, extending to defects from huge tumours and previously inaccessible areas of the skull base. Describe the technique of performing endoscopic double flap multi-layered reconstruction of the anterior skull base without craniotomy. Step by step description of the endoscopic double flap technique (nasoseptal and pericranial vascularized flaps and fascia lata free graft) as used and illustrated in two patients with an olfactory groove meningioma who underwent an endoscopic approach. Both patients achieved a gross total resection: subsequent reconstruction of the anterior skull base was performed with the nasoseptal and pericranial flaps onlay and a fascia lata free graft inlay. Both patients showed an excellent recovery, no signs of cerebrospinal fluid leak, meningitis, flap necrosis, chronic meningeal or sinonasal inflammation or cerebral herniation having developed. This endoscopic double flap technique we have described is a viable, versatile and safe option for anterior skull base reconstructions, decreasing the incidence of complications in endoscopic endonasal approaches. Copyright © 2018 Associação Brasileira de Otorrinolaringologia e Cirurgia Cérvico-Facial. Published by Elsevier Editora Ltda. All rights reserved.

Engineering Ultra-Low Work Function of Graphene.

PubMed

Yuan, Hongyuan; Chang, Shuai; Bargatin, Igor; Wang, Ning C; Riley, Daniel C; Wang, Haotian; Schwede, Jared W; Provine, J; Pop, Eric; Shen, Zhi-Xun; Pianetta, Piero A; Melosh, Nicholas A; Howe, Roger T

2015-10-14

Low work function materials are critical for energy conversion and electron emission applications. Here, we demonstrate for the first time that an ultralow work function graphene is achieved by combining electrostatic gating with a Cs/O surface coating. A simple device is built from large-area monolayer graphene grown by chemical vapor deposition, transferred onto 20 nm HfO2 on Si, enabling high electric fields capacitive charge accumulation in the graphene. We first observed over 0.7 eV work function change due to electrostatic gating as measured by scanning Kelvin probe force microscopy and confirmed by conductivity measurements. The deposition of Cs/O further reduced the work function, as measured by photoemission in an ultrahigh vacuum environment, which reaches nearly 1 eV, the lowest reported to date for a conductive, nondiamond material.

Ultralow Thermal Conductivity in Full Heusler Semiconductors.

PubMed

He, Jiangang; Amsler, Maximilian; Xia, Yi; Naghavi, S Shahab; Hegde, Vinay I; Hao, Shiqiang; Goedecker, Stefan; Ozoliņš, Vidvuds; Wolverton, Chris

2016-07-22

Semiconducting half and, to a lesser extent, full Heusler compounds are promising thermoelectric materials due to their compelling electronic properties with large power factors. However, intrinsically high thermal conductivity resulting in a limited thermoelectric efficiency has so far impeded their widespread use in practical applications. Here, we report the computational discovery of a class of hitherto unknown stable semiconducting full Heusler compounds with ten valence electrons (X_{2}YZ, X=Ca, Sr, and Ba; Y=Au and Hg; Z=Sn, Pb, As, Sb, and Bi) through high-throughput ab initio screening. These new compounds exhibit ultralow lattice thermal conductivity κ_{L} close to the theoretical minimum due to strong anharmonic rattling of the heavy noble metals, while preserving high power factors, thus resulting in excellent phonon-glass electron-crystal materials.

Chromatic dispersion effects in ultra-low coherence interferometry

DOE Office of Scientific and Technical Information (OSTI.GOV)

Lychagov, V V; Ryabukho, V P

2015-06-30

We consider the properties of an interference signal shift from zero-path-difference position in the presence of an uncompensated dispersive layer in one of the interferometer arms. It is experimentally shown that in using an ultra-low coherence light source, the formation of the interference signal is also determined by the group velocity dispersion, which results in a nonlinear dependence of the position of the interference signal on the geometrical thickness of the dispersive layer. The discrepancy in the dispersive layer and compensator refractive indices in the third decimal place is experimentally shown to lead to an interference signal shift that ismore » an order of magnitude greater than the pulse width. (interferometry)« less

Thoracoscopic cartilage resection with partial perichondrium preservation in unilateral pectus carinatum: preliminary results.

PubMed

Varela, Patricio; Torre, Michele

2011-01-01

Although minimally invasive repair of pectus excavatum has gained worldwide acceptance, treatment of pectus carinatum is mostly performed with open procedures. Different minimally invasive alternatives have been proposed in the last few years, including subpectoral CO(2) dissection and intrathoracic compression (Abramson technique), or conservative procedures, as dynamic compression system. Recently, another surgical technique has been proposed for the treatment of unilateral pectus carinatum, consisting of a thoracoscopic approach and multiple cartilage incisions. The aim of this work is to present our modification to this approach. We have modified this technique by introducing complete cartilage resection of all anomalous costal cartilages, performed thoracoscopically. Three thoracoscopic ports were used. Cartilage is removed progressively using a rongeur and preserving the anterior perichondrium. We have performed this technique in 4 patients during the last year. Follow-up ranged from 6 to 14 months. No intraoperative or postoperative complications were observed. The results, assessed by the patients themselves, were good in 2 cases, quite good in one, and fair in the first patient of our series, who was reoperated using a classical open approach. Pain was well controlled without the need of an epidural catheter. Thoracoscopic cartilage resection with perichondrium preservation can be considered as feasible alternative for the treatment of unilateral pectus carinatum. Copyright © 2011 Elsevier Inc. All rights reserved.

How Many Ultra-Low Delta-v Near Earth Objects Remain Undiscovered? Implications for missions.

NASA Astrophysics Data System (ADS)

Elvis, Martin; Ranjan, Sukrit; Galache, Jose Luis; Murphy, Max

2015-08-01

The past decade has witnessed considerable growth of interest in missions to Near-Earth Objects (NEOs). NEOs are considered prime targets for manned and robotic missions, for both scientific objectives as well as in-situ resource utilization including harvesting of water for propellant and life support and mining of high-value elements for sale on Earth. Appropriate targets are crucial to such missions. Hence, ultra-low delta-v mission targets are strongly favored. Some mission architectures rely on the discovery of more ultra-low delta-v NEOs. In fact the approved and executed NEO missions have all targeted asteroids with ultra-low LEO to asteroid rendezvous delta-v <5.5 km/s.In this paper, we estimate the total NEO population as a function of delta-v, and how many remain to be discovered in various size ranges down to ~100m. We couple the NEOSSat-1 model (Greenstreet et al., 2012) to the NEO size distribution derived from the NEOWISE survey (Mainzer et al., 2011b) to compute an absolute NEO population model. We compare the Minor Planet Center (MPC) catalog of known NEOs to this NEO population model. We compute the delta-v from LEO to asteroid rendezvous orbits using a modified Shoemaker-Helin (S-H) formalism that empirically removes biases found comparing S-H with the results from NHATS. The median delta-v of the known NEOs is 7.3 km/s, the median delta-v predicted by our NEO model is 9.8 km/s, suggesting that undiscovered objects are biased to higher delta-v. The survey of delta-v <10.3 km/s NEOs is essentially complete for objects with diameter D >300 m. However, there are tens of thousands of objects with delta-v <10.3 km/s to be discovered in the D = 50 - 300 m size class (H = 20.4 - 24.3). Our work suggests that there are 100 yet-undiscovered NEOs with delta-v < 5:8 km/s, and 1000 undiscovered NEOs with v < 6.3 km/s. We conclude that, even with complete NEO surveys, the selection of good (i.e. ultra-low delta-v) mission targets is limited given current

Left Transsylvian Transcisternal and Transinferior Insular Sulcus Approach for Resection of Uncohippocampal Tumor: 3-Dimensional Operative Video.

PubMed

Fernandez-Miranda, Juan C

2018-06-07

The medial temporal lobe can be divided in anterior, middle, and posterior segments. The anterior segment is formed by the uncus and hippocampal head, and it has extra and intraventricular structures. There are 2 main approaches to the uncohippocampal region, the anteromedial temporal lobectomy (Spencer's technique) and the transsylvian selective amygdalohippocampectomy (Yasargil's technique).In this video, we present the case of a 29-yr-old man with new onset of generalized seizures and a contrast-enhancing lesion in the left anterior segment of the medial temporal lobe compatible with high-grade glioma. He had a medical history of cervical astrocytoma at age 8 requiring craniospinal radiation therapy and ventriculoperitoneal shunt placement.The tumor was approached using a combined transsylvian transcisternal and transinferior insular sulcus approach to the extra and intraventricular aspects of the uncohippocampal region. It was resected completely, and the patient was neurologically intact after resection with no further seizures at 6-mo follow-up. The diagnosis was glioblastoma IDH-wild type, for which he underwent adjuvant therapy.Surgical anatomy and technical nuances of this approach are illustrated using a 3-dimensional video and anatomic dissections. The selective approach, when compared to an anteromedial temporal lobectomy, has the advantage of preserving the anterolateral temporal cortex, which is particularly relevant in dominant-hemisphere lesions, and the related fiber tracts, including the inferior fronto-occipital and inferior longitudinal fascicles, and most of the optic radiation fibers. The transsylvian approach, however, is technically and anatomically more challenging and potentially carries a higher risk of vascular injury and vasospasm.Page 1 and figures from Fernández-Miranda JC et al, Microvascular Anatomy of the Medial Temporal Region: Part 1: Its Application to Arteriovenous Malformation Surgery, Operative Neurosurgery, 2010, Volume 67

GeneImp: Fast Imputation to Large Reference Panels Using Genotype Likelihoods from Ultralow Coverage Sequencing

PubMed Central

Spiliopoulou, Athina; Colombo, Marco; Orchard, Peter; Agakov, Felix; McKeigue, Paul

2017-01-01

We address the task of genotype imputation to a dense reference panel given genotype likelihoods computed from ultralow coverage sequencing as inputs. In this setting, the data have a high-level of missingness or uncertainty, and are thus more amenable to a probabilistic representation. Most existing imputation algorithms are not well suited for this situation, as they rely on prephasing for computational efficiency, and, without definite genotype calls, the prephasing task becomes computationally expensive. We describe GeneImp, a program for genotype imputation that does not require prephasing and is computationally tractable for whole-genome imputation. GeneImp does not explicitly model recombination, instead it capitalizes on the existence of large reference panels—comprising thousands of reference haplotypes—and assumes that the reference haplotypes can adequately represent the target haplotypes over short regions unaltered. We validate GeneImp based on data from ultralow coverage sequencing (0.5×), and compare its performance to the most recent version of BEAGLE that can perform this task. We show that GeneImp achieves imputation quality very close to that of BEAGLE, using one to two orders of magnitude less time, without an increase in memory complexity. Therefore, GeneImp is the first practical choice for whole-genome imputation to a dense reference panel when prephasing cannot be applied, for instance, in datasets produced via ultralow coverage sequencing. A related future application for GeneImp is whole-genome imputation based on the off-target reads from deep whole-exome sequencing. PMID:28348060

Augmented reality in a tumor resection model.

PubMed

Chauvet, Pauline; Collins, Toby; Debize, Clement; Novais-Gameiro, Lorraine; Pereira, Bruno; Bartoli, Adrien; Canis, Michel; Bourdel, Nicolas

2018-03-01

Augmented Reality (AR) guidance is a technology that allows a surgeon to see sub-surface structures, by overlaying pre-operative imaging data on a live laparoscopic video. Our objectives were to evaluate a state-of-the-art AR guidance system in a tumor surgical resection model, comparing the accuracy of the resection with and without the system. Our system has three phases. Phase 1: using the MRI images, the kidney's and pseudotumor's surfaces are segmented to construct a 3D model. Phase 2: the intra-operative 3D model of the kidney is computed. Phase 3: the pre-operative and intra-operative models are registered, and the laparoscopic view is augmented with the pre-operative data. We performed a prospective experimental study on ex vivo porcine kidneys. Alginate was injected into the parenchyma to create pseudotumors measuring 4-10 mm. The kidneys were then analyzed by MRI. Next, the kidneys were placed into pelvictrainers, and the pseudotumors were laparoscopically resected. The AR guidance system allows the surgeon to see tumors and margins using classical laparoscopic instruments, and a classical screen. The resection margins were measured microscopically to evaluate the accuracy of resection. Ninety tumors were segmented: 28 were used to optimize the AR software, and 62 were used to randomly compare surgical resection: 29 tumors were resected using AR and 33 without AR. The analysis of our pathological results showed 4 failures (tumor with positive margins) (13.8%) in the AR group, and 10 (30.3%) in the Non-AR group. There was no complete miss in the AR group, while there were 4 complete misses in the non-AR group. In total, 14 (42.4%) tumors were completely missed or had a positive margin in the non-AR group. Our AR system enhances the accuracy of surgical resection, particularly for small tumors. Crucial information such as resection margins and vascularization could also be displayed.

Non-Exposure, Device-Assisted Endoscopic Full-thickness Resection.

PubMed

Bauder, Markus; Schmidt, Arthur; Caca, Karel

2016-04-01

Recent developments have expanded the frontier of interventional endoscopy toward more extended resections following surgical principles. This article presents two new device-assisted techniques for endoscopic full-thickness resection in the upper and lower gastrointestinal tract. Both methods are nonexposure techniques avoiding exposure of gastrointestinal contents to the peritoneal cavity by a "close first-cut later" principle. The full-thickness resection device is a novel over-the-scope device designed for clip-assisted full-thickness resection of colorectal lesions. Endoscopic full-thickness resection of gastric subepithelial tumors can be performed after placing transmural sutures underneath the tumor with a suturing device originally designed for endoscopic antireflux therapy. Copyright © 2016 Elsevier Inc. All rights reserved.

a-SiNx:H-based ultra-low power resistive random access memory with tunable Si dangling bond conduction paths.

PubMed

Jiang, Xiaofan; Ma, Zhongyuan; Xu, Jun; Chen, Kunji; Xu, Ling; Li, Wei; Huang, Xinfan; Feng, Duan

2015-10-28

The realization of ultra-low power Si-based resistive switching memory technology will be a milestone in the development of next generation non-volatile memory. Here we show that a high performance and ultra-low power resistive random access memory (RRAM) based on an Al/a-SiNx:H/p(+)-Si structure can be achieved by tuning the Si dangling bond conduction paths. We reveal the intrinsic relationship between the Si dangling bonds and the N/Si ratio x for the a-SiNx:H films, which ensures that the programming current can be reduced to less than 1 μA by increasing the value of x. Theoretically calculated current-voltage (I-V) curves combined with the temperature dependence of the I-V characteristics confirm that, for the low-resistance state (LRS), the Si dangling bond conduction paths obey the trap-assisted tunneling model. In the high-resistance state (HRS), conduction is dominated by either hopping or Poole-Frenkel (P-F) processes. Our introduction of hydrogen in the a-SiNx:H layer provides a new way to control the Si dangling bond conduction paths, and thus opens up a research field for ultra-low power Si-based RRAM.

On the elimination of pulse wave velocity in stroke volume determination from the ultralow-frequency displacement ballistocardiogram.

DOT National Transportation Integrated Search

1964-03-01

A hydrodynamic model of the systemic circulatory system was mounted on an ultralow-frequency ballistocardiograph (ULF-BCG). The relationship between stroke volume and ballistocardiographic amplitude was investigated for different pulse wave velocitie...

Direct Observation of Ultralow Vertical Emittance using a Vertical Undulator

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wootton, Kent

2015-09-17

In recent work, the first quantitative measurements of electron beam vertical emittance using a vertical undulator were presented, with particular emphasis given to ultralow vertical emittances [K. P. Wootton, et al., Phys. Rev. ST Accel. Beams, 17, 112802 (2014)]. Using this apparatus, a geometric vertical emittance of 0.9 ± 0.3 pm rad has been observed. A critical analysis is given of measurement approaches that were attempted, with particular emphasis on systematic and statistical uncertainties. The method used is explained, compared to other techniques and the applicability of these results to other scenarios discussed.

Multiwavelength ultralow-threshold lasing in quantum dot photonic crystal microcavities.

PubMed

Chakravarty, S; Bhattacharya, P; Chakrabarti, S; Mi, Z

2007-05-15

We demonstrate multiwavelength lasing of resonant modes in linear (L3) microcavities in a triangular-lattice 2D photonic crystal (PC) slab. The broad spontaneous emission spectrum from coupled quantum dots, modified by the PC microcavity, is studied as a function of the intensity of incident optical excitation. We observe lasing with an ultralow-threshold power of approximately 600 nW and an output efficiency of approximately 3% at threshold. Two other resonant modes exhibit weaker turnon characteristics and thresholds of approximately 2.5 and 200 microW, respectively.

Simulation study on AlGaN/GaN diode with Γ-shaped anode for ultra-low turn-on voltage

NASA Astrophysics Data System (ADS)

Wang, Zeheng; Chen, Wanjun; Wang, Fangzhou; Cao, Jun; Sun, Ruize; Ren, Kailin; Luo, Yi; Guo, Songnan; Wang, Zirui; Jin, Xiaosheng; Yang, Lei; Zhang, Bo

2018-05-01

An ultra-low turn-on voltage (VT) Γ-shaped anode AlGaN/GaN Schottky barrier diode (GA-SBD) is proposed via modeling and simulation for the first time, in which a Γ-shaped anode consists of a metal-2DEG junction together with a metal-AlGaN junction beside a shallowly recessed MIS field plate (MFP). An analytic forward current-voltage model matching the simulation results well is presented where an ultra-low VT of 0.08 V is obtained. The turn-on and blocking mechanisms are investigated to reveal the GA-SBD's great potential for applications of highly efficient power ICs.

Resonance magnetoplasticity in ultralow magnetic fields

NASA Astrophysics Data System (ADS)

Alshits, V. I.; Darinskaya, E. V.; Koldaeva, M. V.; Petrzhik, E. A.

2016-09-01

Resonance relaxation displacements of dislocations in NaCl crystals placed in crossed static and alternating ultralow magnetic fields in the electron paramagnetic resonance scheme are discussed. The Earth's magnetic field B Earth ≈ 50μT and other fields in the range of 26-261 μT are used as the static field. New strongly anisotropic properties of the effect have been revealed. Frequency spectra including numerous peaks of paths at low pump frequencies beginning with 10 kHz, as well as the quartet of equidistant peaks at high frequencies ( 1.4 MHz at B= B Earth), have been measured. The effect is also observed in the pulsed pump field with a resonance duration of 0.5 μs. Resonance changes have been detected in the microhardness of ZnO, triglycine sulfate, and potassium hydrogen phthalate crystals after their exposure in the Earth's magnetic field in the same electron paramagnetic resonance scheme.

The long-term results of resection and multiple resections in Crohn's disease.

PubMed

Krupnick, A S; Morris, J B

2000-01-01

Crohn's disease is a panenteric, transmural inflammatory disease of unknown origin. Although primarily managed medically, 70% to 90% of patients will require surgical intervention. Surgery for small bowel Crohn's is usually necessary for unrelenting stenotic complications of the disease. Fistula, abscess, and perforation can also necessitate surgical intervention. Most patients benefit from resection or strictureplasty with an improved quality of life and remission of disease, but recurrence is common and 33% to 82% of patients will need a second operation, and 22% to 33% will require more than two resections. Short-bowel syndrome is unavoidable in a small percentage of Crohn's patients because of recurrent resection of affected small bowel and inflammatory destruction of the remaining mucosa. Although previously a lethal and unrelenting disease with death caused by malnutrition, patients with short-bowel syndrome today can lead productive lives with maintenance on total parenteral nutrition (TPN). This lifestyle, however, does not come without a price. Severe TPN-related complications, such as sepsis of indwelling central venous catheters and liver failure, do occur. Future developments will focus on more powerful and effective anti-inflammatory medication specifically targeting the immune mechanisms responsible for Crohn's disease. Successful medical management of the disease will alleviate the need for surgical resection and reduce the frequency of short-bowel syndrome. Improving the efficacy of immunosuppression and the understanding of tolerance induction should increase the safety and applicability of small-bowel transplant for those with short gut. Tissue engineering offers the potential to avoid immunosuppression altogether and supplement intestinal length using the patient's own tissues.

Randomized clinical trial of oral and intravenous versus intravenous antibiotic prophylaxis for laparoscopic colorectal resection.

PubMed

Ikeda, A; Konishi, T; Ueno, M; Fukunaga, Y; Nagayama, S; Fujimoto, Y; Akiyoshi, T; Yamaguchi, T

2016-11-01

The use of oral prophylactic antibiotics for the prevention of surgical-site infection (SSI) in patients undergoing laparoscopic surgery for colorectal cancer is controversial. The aim of this RCT was to evaluate whether intravenous perioperative antibiotics are inferior to combined preoperative oral and perioperative intravenous antibiotics in this setting. Patients undergoing elective laparoscopic colorectal resection in a single cancer centre were assigned randomly to combined preoperative oral antibiotics (metronidazole and kanamycin) and perioperative intravenous antibiotics (cefmetazole) (oral/IV group) or to perioperative intravenous antibiotics (cefmetazole) alone (IV-only group). Patients were stratified for the analyses based on type of operation (colonic surgery, anterior resection or abdominoperineal resection), preoperative use of mechanical bowel preparation, preoperative chemoradiotherapy and the presence of diabetes mellitus. The primary endpoint was the overall rate of SSI. Secondary endpoints were the rates of incisional site infection, organ/space infection, anastomotic leakage, intra-abdominal abscess, adverse events and postoperative complications. Of 540 patients offered participation in the trial in 2013-2014, 515 agreed to take part and were randomized. Some 256 patients in the IV-only group and 255 in the oral/IV group completed the treatment per protocol. The overall rate of SSI was 7·8 per cent (20 of 256) in the IV-only group and 7·8 per cent (20 of 255) in the oral/IV group, confirming that perioperative administration of intravenous antibiotics alone was not inferior to the combined regimen (P = 0·017). There were no differences in rates of incisional site infection (5·5 versus 5·9 per cent respectively), organ/space infection (2·3 versus 2·0 per cent) or other secondary endpoints between the two groups. Intravenous perioperative antimicrobial prophylaxis alone is not inferior to combined preoperative oral and intravenous

Chemical reactions studied at ultra-low temperature in liquid helium clusters

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huisken, Friedrich; Krasnokutski, Serge A.

Low-temperature reaction rates are important ingredients for astrophysical reaction networks modeling the formation of interstellar matter in molecular clouds. Unfortunately, such data is difficult to obtain by experimental means. In an attempt to study low-temperature reactions of astrophysical interest, we have investigated relevant reactions at ultralow temperature in liquid helium droplets. Being prepared by supersonic expansion of helium gas at high pressure through a nozzle into a vacuum, large helium clusters in the form of liquid droplets constitute nano-sized reaction vessels for the study of chemical reactions at ultra-low temperature. If the normal isotope {sup 4}He is used, the heliummore » droplets are superfluid and characterized by a constant temperature of 0.37 K. Here we present results obtained for Mg, Al, and Si reacting with O{sub 2}. Mass spectrometry was employed to characterize the reaction products. As it may be difficult to distinguish between reactions occurring in the helium droplets before they are ionized and ion-molecule reactions taking place after the ionization, additional techniques were applied to ensure that the reactions actually occurred in the helium droplets. This information was provided by measuring the chemiluminescence light emitted by the products, the evaporation of helium atoms by the release of the reaction heat, or by laser-spectroscopic identification of the reactants and products.« less

Anterior transarticular C1-C2 fixation with contralateral screw insertion: a report of two cases and technical note.

PubMed

Lvov, Ivan; Grin, Andrey; Kaykov, Aleksandr; Smirnov, Vladimir; Krylov, Vladimir

2017-08-08

Anterior transarticular fixation of the C1-C2 vertebrae is a well-known technique that involves screw insertion through the body of the C2 vertebra into the lateral masses of the atlas through an anterior transcervical approach. Meanwhile, contralateral screw insertion has been previously described only in anatomical studies. We describe two case reports of the clinical application of this new technique. In Case 1, the patient was diagnosed with an unstable C1 fracture. The clinical features of the case did not allow for any type of posterior atlantoaxial fusion, Halo immobilization, or routine anterior fixation using the Reindl and Koller techniques. The possible manner of screw insertion into the anterior third of the right lateral mass was via a contralateral trajectory, which was performed in this case. Case 2 involved a patient with neglected posteriorly dislocated dens fracture who could not lie in the prone position due to concomitant cardiac pathology. Reduction of atlantoaxial dislocation was insufficient, even after scar tissue resection at the fracture, while transdental fusion was not possible. Considering the success of the previous case, atlantoaxial fixation was performed through the small approach, using the Reindl technique and contralateral screw insertion. These two cases demonstrate the potential of anterior transarticular fixation of C1-C2 vertebrae in cases where posterior atlantoaxial fusion is not achievable. This type of fixation can be performed through a single approach if one screw is inserted using the Reindl technique and another is inserted via a contralateral trajectory.

Laparoscopic liver resection for malignancy: a review of the literature.

PubMed

Alkhalili, Eyas; Berber, Eren

2014-10-07

To review the published literature about laparoscopic liver resection for malignancy. A PubMed search was performed for original published studies until June 2013 and original series containing at least 30 patients were reviewed. All forms of hepatic resections have been described ranging from simple wedge resections to extended right or left hepatectomies. The usual approach is pure laparoscopic, but hand-assisted, as well as robotic approaches have been described. Most studies showed comparable results to open resection in terms of operative blood loss, postoperative morbidity and mortality. Many of them showed decreased postoperative pain, shorter hospital stays, and even lower costs. Oncological results including resection margin status and long-term survival were not inferior to open resection. In the hands of experienced surgeons, laparoscopic liver resection for malignant lesions is safe and offers some short-term advantages over open resection. Oncologically, similar survival rates have been observed in patients treated with the laparoscopic approach when compared to their open resection counterparts.

Abdominal CT with model-based iterative reconstruction (MBIR): initial results of a prospective trial comparing ultralow-dose with standard-dose imaging.

PubMed

Pickhardt, Perry J; Lubner, Meghan G; Kim, David H; Tang, Jie; Ruma, Julie A; del Rio, Alejandro Muñoz; Chen, Guang-Hong

2012-12-01

The purpose of this study was to report preliminary results of an ongoing prospective trial of ultralow-dose abdominal MDCT. Imaging with standard-dose contrast-enhanced (n = 21) and unenhanced (n = 24) clinical abdominal MDCT protocols was immediately followed by ultralow-dose imaging of a matched series of 45 consecutively registered adults (mean age, 57.9 years; mean body mass index, 28.5). The ultralow-dose images were reconstructed with filtered back projection (FBP), adaptive statistical iterative reconstruction (ASIR), and model-based iterative reconstruction (MBIR). Standard-dose series were reconstructed with FBP (reference standard). Image noise was measured at multiple predefined sites. Two blinded abdominal radiologists interpreted randomly presented ultralow-dose images for multilevel subjective image quality (5-point scale) and depiction of organ-based focal lesions. Mean dose reduction relative to the standard series was 74% (median, 78%; range, 57-88%; mean effective dose, 1.90 mSv). Mean multiorgan image noise for low-dose MBIR was 14.7 ± 2.6 HU, significantly lower than standard-dose FBP (28.9 ± 9.9 HU), low-dose FBP (59.2 ± 23.3 HU), and ASIR (45.6 ± 14.1 HU) (p < 0.001). The mean subjective image quality score for low-dose MBIR (3.0 ± 0.5) was significantly higher than for low-dose FBP (1.6 ± 0.7) and ASIR (1.8 ± 0.7) (p < 0.001). Readers identified 213 focal noncalcific lesions with standard-dose FBP. Pooled lesion detection was higher for low-dose MBIR (79.3% [169/213]) compared with low-dose FBP (66.2% [141/213]) and ASIR (62.0% [132/213]) (p < 0.05). MBIR shows great potential for substantially reducing radiation doses at routine abdominal CT. Both FBP and ASIR are limited in this regard owing to reduced image quality and diagnostic capability. Further investigation is needed to determine the optimal dose level for MBIR that maintains adequate diagnostic performance. In general, objective and subjective image quality measurements do

Prevention of internal hernias and pelvic adhesions following laparoscopic left-sided colorectal resection: the role of fibrin sealant.

PubMed

Angelini, Pierluigi; Sciuto, Antonio; Cuccurullo, Diego; Pirozzi, Felice; Reggio, Stefano; Corcione, Francesco

2017-07-01

Laparoscopy has increasingly become the standard of care for patients who undergo colorectal surgery for both benign and malignant diseases. This growing experience has also resulted in more reports of postoperative complications from the minimally invasive approach to primary colorectal resection. Small bowel obstruction from internal hernias and pre-sacral adhesions is an uncommon but not negligible complication. However, there is little literature specific to this topic with recommendations for different methods to prevent it. We report our original technique of closing the mesenteric defect and covering the pre-sacral fascia by using fibrin sealant to prevent this complication. From January 2005 to December 2014, a total of 1079 patients underwent elective laparoscopic left colorectal resection (left hemicolectomy or anterior rectal resection) in our department. In the first 298 procedures, the mesenteric defect was left open, while in the following 781 procedures, it was closed using fibrin sealant with the aim of preventing postoperative small bowel obstruction. Among the first 298 patients, three (1%) required reoperation for small bowel obstruction due to internal hernia (0.33%) or critical pre-sacral adhesions (0.66%). These complications did not occur in the subsequent series in which all 781 patients were treated with fibrin sealant prophylactic closure of the mesenteric defect. In our experience, fibrin sealant closure of the mesenteric defect has demonstrated to be safe and effective in preventing postoperative small bowel obstruction that remains a complication both in open and in laparoscopic colorectal surgeries.

Functional outcomes after shoulder resection: the patient's perspective.

PubMed

Stevens, Nicole M; Kim, H Mike; Armstrong, April D

2015-09-01

Resection arthroplasty is a salvage procedure used for the treatment of deep-seated infections after total shoulder arthroplasty, hemiarthroplasty, and reverse total shoulder arthroplasty. Previous studies have reported a 50% to 66% rate of pain relief after resection arthroplasty but with significant functional limitations. Our study aimed to qualify the perspective of the patients on their limitations and satisfaction with resection arthroplasty. A retrospective record review of resection arthroplasties performed between September 2003 and December 2012 yielded 14 patients, and 7 completed the survey. The patients completed surveys with the focus on the "patient perspective." Functional scores, including American Shoulder and Elbow Surgeons, Simple Shoulder Test, Disabilities of the Arm, Shoulder, and Hand (DASH), DASH work, and DASH sports, were determined. Pain reduction and functional outcomes were similar to past reports of resection arthroplasty. Five of the 7 patients (71%) reported satisfaction with their resection arthroplasty, and 6 of the 7 patients (86%) would undergo the procedure again if given the choice. Five of the 7 patients (71%) were able to most of activities of daily living. Patients in our study were generally satisfied with their resection arthroplasty. Resection arthroplasty is a reasonable option for treatment of deep-seated periprosthetic infections or for patients with multiple previous failed procedures for total shoulder arthroplasty, hemiarthroplasty. and reverse shoulder arthroplasty. Copyright © 2015 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

MDCT assessment of resectability in hilar cholangiocarcinoma.

PubMed

Ni, Qihong; Wang, Haolu; Zhang, Yunhe; Qian, Lijun; Chi, Jiachang; Liang, Xiaowen; Chen, Tao; Wang, Jian

2017-03-01

The purpose of this study is to investigate the value of multidetector computed tomography (MDCT) assessment of resectability in hilar cholangiocarcinoma, and to identify the factors associated with unresectability and accurate evaluation of resectability. From January 2007 to June 2015, a total of 77 consecutive patients were included. All patients had preoperative MDCT (with MPR and MinIP) and surgical treatment, and were pathologically proven with hilar cholangiocarcinoma. The MDCT images were reviewed retrospectively by two senior radiologists and one hepatobiliary surgeon. The surgical findings and pathologic results were considered to be the gold standard. The Chi square test was used to identify factors associated with unresectability and accurate evaluation of resectability. The sensitivity, specificity, and overall accuracy of MDCT assessment were 83.3 %, 75.9 %, and 80.5 %, respectively. The main causes of inaccuracy were incorrect evaluation of N2 lymph node metastasis (4/15) and distant metastasis (4/15). Bismuth type IV tumor, main or bilateral hepatic artery involvement, and main or bilateral portal vein involvement were highly associated with unresectability (P < 0.001). Patients without biliary drainage had higher accuracy of MDCT evaluation of resectability compared to those with biliary drainage (P < 0.001). MDCT is reliable for preoperative assessment of resectability in hilar cholangiocarcinoma. Bismuth type IV tumor and main or bilateral vascular involvement highly suggest the unresectability of hilar cholangiocarcinoma. Patients without biliary drainage have a more accurate MDCT evaluation of resectability. We suggest MDCT should be performed before biliary drainage to achieve an accurate evaluation of resectability in hilar cholangiocarcinoma.

Super non-linear RRAM with ultra-low power for 3D vertical nano-crossbar arrays.

PubMed

Luo, Qing; Xu, Xiaoxin; Liu, Hongtao; Lv, Hangbing; Gong, Tiancheng; Long, Shibing; Liu, Qi; Sun, Haitao; Banerjee, Writam; Li, Ling; Gao, Jianfeng; Lu, Nianduan; Liu, Ming

2016-08-25

Vertical crossbar arrays provide a cost-effective approach for high density three-dimensional (3D) integration of resistive random access memory. However, an individual selector device is not allowed to be integrated with the memory cell separately. The development of V-RRAM has impeded the lack of satisfactory self-selective cells. In this study, we have developed a high performance bilayer self-selective device using HfO2 as the memory switching layer and a mixed ionic and electron conductor as the selective layer. The device exhibits high non-linearity (>10(3)) and ultra-low half-select leakage (<0.1 pA). A four layer vertical crossbar array was successfully demonstrated based on the developed self-selective device. High uniformity, ultra-low leakage, sub-nA operation, self-compliance, and excellent read/write disturbance immunity were achieved. The robust array level performance shows attractive potential for low power and high density 3D data storage applications.

Single-mode large-mode-area laser fiber with ultralow numerical aperture and high beam quality.

PubMed

Peng, Kun; Zhan, Huan; Ni, Li; Wang, Xiaolong; Wang, Yuying; Gao, Cong; Li, Yuwei; Wang, Jianjun; Jing, Feng; Lin, Aoxiang

2016-12-10

By using the chelate precursor doping technique, we report on an ytterbium-doped aluminophosphosilicate (APS) large-mode-area fiber with ultralow numerical aperture of 0.036 and effective fundamental mode area of ∼550  μm². With a bend diameter of 600 mm, the bending loss of fundamental mode LP₀₁ was measured to be <10^-3  dB/m, in agreement with the corresponding simulation results, while that of higher order mode LP₁₁ is >100  dB/m at 1080 nm. Measured in an all-fiber oscillator laser cavity, 592 W single-mode laser output was obtained at 1079.64 nm with high-beam quality M² of 1.12. The results indicate that the chelate precursor doping technique is a competitive method for ultralow numerical aperture fiber fabrication, which is very suitable for developing single-mode seed lasers for high power laser systems.

[Electric traction magnetic fields of ultra-low frequency as an occupational risk factor of ischemic heart disease].

PubMed

Ptitsyna, N G; Kudrin, V A; Villorezi, D; Kopytenko, Iu A; Tiasto, M I; Kopytenko, E A; Bochko, V A; Iuchchi, N

1996-01-01

The study was inspired by earlier results that displayed influence of variable natural geomagnetic field (0.005-10 Hz range-ultra-low frequencies) on circulatory system, indicated possible correlation between industrial ultra-low frequency fields and prevalence of myocardial infarction. The authors conducted unique measurements of ultra-low frequency fields produced by electric engines. The results were compared with data on morbidity among railway transport workers. The findings are that level of magnetic variations in electric locomotive cabin can exceed 280 micro Tesla, whereas that in car sections reaches 50 micro Tesla. Occurrence of coronary heart disease among the locomotive operators appeared to be 2.0 + 0.2 times higher than that among the car section operators. Higher risk of coronary heart disease in the locomotive operators is associated with their increased occupational magnetic load.

Coblation-assisted endonasal endoscopic resection of juvenile nasopharyngeal angiofibroma.

PubMed

Ye, L; Zhou, X; Li, J; Jin, J

2011-09-01

Juvenile nasopharyngeal angiofibroma may be successfully resected using endoscopic techniques. However, the use of coblation technology for such resection has not been described. This study aimed to document cases of Fisch class I juvenile nasopharyngeal angiofibroma with limited nasopharyngeal and nasal cavity extension, which were completely resected using an endoscopic coblation technique. We retrospectively studied 23 patients with juvenile nasopharyngeal angiofibroma who underwent resection with either traditional endoscopic instruments (n = 12) or coblation (n = 11). Intra-operative blood loss and overall operative time were recorded. The mean tumour resection time for coblation and traditional endoscopic instruments was 87 and 136 minutes, respectively (t = 9.962, p < 0.001). Mean intra-operative blood loss was 121 and 420 ml, respectively (t = 28.944, p < 0.001), a significant difference. Both techniques achieved complete tumour resection with minimal damage to adjacent tissues, and no recurrence in any patient. Coblation successfully achieves transnasal endoscopic resection of juvenile nasopharyngeal angiofibroma (Fisch class I), with good surgical margins and minimal blood loss.

Performance study of personal inhalable aerosol samplers at ultra-low wind speeds.

PubMed

Sleeth, Darrah K; Vincent, James H

2012-03-01

The assessment of personal inhalable aerosol samplers in a controlled laboratory setting has not previously been carried out at the ultra-low wind speed conditions that represent most modern workplaces. There is currently some concern about whether the existing inhalable aerosol convention is appropriate at these low wind speeds and an alternative has been suggested. It was therefore important to assess the performance of the most common personal samplers used to collect the inhalable aerosol fraction, especially those that were designed to match the original curve. The experimental set-up involved use of a hybrid ultra-low speed wind tunnel/calm air chamber and a rotating, heating breathing mannequin to measure the inhalable fraction of aerosol exposure. The samplers that were tested included the Institute of Occupational Medicine (IOM), Button, and GSP inhalable samplers as well as the closed-face cassette sampler that has been (and still is) widely used by occupational hygienists in many countries. The results showed that, down to ∼0.2 m s(-1), the samplers matched the current inhalability criterion relatively well but were significantly greater than this at the lowest wind speed tested. Overall, there was a significant effect of wind speed on sampling efficiency, with lower wind speeds clearly associated with an increase in sampling efficiency.

New Technique for Liver Resection Using Heat Coagulative Necrosis

PubMed Central

Weber, Jean-Christophe; Navarra, Giuseppe; Jiao, Long R.; Nicholls, Joanna P.; Jensen, Steen Lindkaer; Habib, Nagy A.

2002-01-01

Objective To assess a new bloodless technique using radiofrequency energy for segmental liver resection of hepatic tumors. Summary Background Data Liver resection remains a formidable surgical procedure; safe performance requires a high level of training and skill. Intraoperative blood loss during liver resection remains a major concern because it is associated with a higher rate of postoperative complications and shorter long-term survival. Methods From January 2000 to June 2001, 15 patients with various hepatic tumors were operated on using radiofrequency energy to remove the tumor in its entirety. Radiofrequency energy was applied along the margins of the tumor to create “zones of necrosis” before resection with a scalpel. Results No blood transfusions were required. The mean blood loss during resection was 30 ± 10 mL. No mortality or morbidity was observed. The median postoperative stay was 8 days (range 5–9). No liver recurrence was detected in patients undergoing resection with this technique during follow-up periods ranging from 2 to 20 months. Conclusions Segmental and wedge liver resection assisted by radiofrequency is safe. This novel technique offers a new method for transfusion-free resection. PMID:12409660

Molybdenum disulfide for ultra-low detection of free radicals: electrochemical response and molecular modeling

NASA Astrophysics Data System (ADS)

Gupta, Ankur; Rawal, Takat B.; Neal, Craig J.; Das, Soumen; Rahman, Talat S.; Seal, Sudipta

2017-06-01

Two-dimensional (2D) molybdenum disulfide (MoS2) offers attractive properties due to its band gap modulation and has led to significant research-oriented applications (i.e. DNA and protein detection, cell imaging (fluorescent label) etc.). In biology, detection of free radicals (i.e. reactive oxygen species and reactive nitrogen (NO*) species are very important for early discovery and treatment of diseases. Herein, for the first time, we demonstrate the ultra-low (pico-molar) detection of pharmaceutically relevant free radicals using MoS2 for electrochemical sensing. We present pico- to nano- molar level sensitivity in smaller MoS2 with S-deficiency as revealed by x-ray photoelectron spectroscopy. Furthermore, the detection mechanism and size-dependent sensitivity have been investigated by density functional theory (DFT) showing the change in electronic density of states of Mo atoms at edges which lead to the preferred adsorption of H2O2 on Mo edges. The DFT analysis signifies the role of size and S-deficiency in the higher catalytic activity of smaller MoS2 particles and, thus, ultra-low detection.

Management of Nonunited Talar Fractures With Avascular Necrosis by Resection of Necrotic Bone, Bone Grafting, and Fusion With an Intramedullary Nail.

PubMed

Abd-Ella, Mohamed Mokhtar; Galhoum, Ahmed; Abdelrahman, Amr Farouk; Walther, Markus

2017-08-01

The presence of nonunion of a talar fracture with displacement, together with complete avascular necrosis, is a challenging entity to treat. Twelve patients, 8 men (66.7%) and 4 women (33.3%), with nonunited talar fractures and extensive avascular necrosis of the talus were included. The average age was 27.7 years (range, 19-38 years). After exclusion of infection, the patients underwent resection of necrotic bone, bulk autograft, and fusion using an intramedullary nail. The posterior approach was used in 11 patients and the anterior approach in 1 patient. The primary outcome was solid osseous union at the ankle and subtalar level and between the talar head anteriorly and the posterior construct, as evidenced by computed tomographic examination. Functional assessment was performed with the American Orthopaedic Foot & Ankle Society score and subjective patient satisfaction Results: After a mean follow-up duration of 23 months (range, 12-60 months), solid osseous union was achieved in 8 patients (66.7%). Stable fibrous union was seen in 1 patient (8.3%). Three patients (25%) required reoperation, and osseous fusion was finally achieved. American Orthopaedic Foot & Ankle Society score improved from a mean of 39.3 (range, 12-56) preoperatively to 76.6 (range, 62-86) at last follow-up. Subjective patient satisfaction was graded good or excellent in all cases. Resection of necrotic talar body and bulk autograft with tibiotalocalcaneal fusion by an intramedullary nail through a posterior approach was a reasonable option for the management of type IV posttraumatic talar deformity. Level IV, case series.

Laparoscopic liver resection for malignancy: A review of the literature

PubMed Central

Alkhalili, Eyas; Berber, Eren

2014-01-01

AIM: To review the published literature about laparoscopic liver resection for malignancy. METHODS: A PubMed search was performed for original published studies until June 2013 and original series containing at least 30 patients were reviewed. RESULTS: All forms of hepatic resections have been described ranging from simple wedge resections to extended right or left hepatectomies. The usual approach is pure laparoscopic, but hand-assisted, as well as robotic approaches have been described. Most studies showed comparable results to open resection in terms of operative blood loss, postoperative morbidity and mortality. Many of them showed decreased postoperative pain, shorter hospital stays, and even lower costs. Oncological results including resection margin status and long-term survival were not inferior to open resection. CONCLUSION: In the hands of experienced surgeons, laparoscopic liver resection for malignant lesions is safe and offers some short-term advantages over open resection. Oncologically, similar survival rates have been observed in patients treated with the laparoscopic approach when compared to their open resection counterparts. PMID:25309091

Standardizing terminology for minimally invasive pancreatic resection.

PubMed

Montagnini, Andre L; Røsok, Bård I; Asbun, Horacio J; Barkun, Jeffrey; Besselink, Marc G; Boggi, Ugo; Conlon, Kevin C P; Fingerhut, Abe; Han, Ho-Seong; Hansen, Paul D; Hogg, Melissa E; Kendrick, Michael L; Palanivelu, Chinnusamy; Shrikhande, Shailesh V; Wakabayashi, Go; Zeh, Herbert; Vollmer, Charles M; Kooby, David A

2017-03-01

There is a growing body of literature pertaining to minimally invasive pancreatic resection (MIPR). Heterogeneity in MIPR terminology, leads to confusion and inconsistency. The Organizing Committee of the State of the Art Conference on MIPR collaborated to standardize MIPR terminology. After formal literature review for "minimally invasive pancreatic surgery" term, key terminology elements were identified. A questionnaire was created assessing the type of resection, the approach, completion, and conversion. Delphi process was used to identify the level of agreement among the experts. A systematic terminology template was developed based on combining the approach and resection taking into account the completion. For a solitary approach the term should combine "approach + resection" (e.g. "laparoscopic pancreatoduodenectomy); for combined approaches the term must combine "first approach + resection" with "second approach + reconstruction" (e.g. "laparoscopic central pancreatectomy" with "open pancreaticojejunostomy") and where conversion has resulted the recommended term is "first approach" + "converted to" + "second approach" + "resection" (e.g. "robot-assisted" "converted to open" "pancreatoduodenectomy") CONCLUSIONS: The guidelines presented are geared towards standardizing terminology for MIPR, establishing a basis for comparative analyses and registries and allow incorporating future surgical and technological advances in MIPR. Copyright © 2017 International Hepato-Pancreato-Biliary Association Inc. Published by Elsevier Ltd. All rights reserved.

Endoscopic resection of acetabular screw tip to decompress sciatic nerve following total hip arthroplasty.

PubMed

Yoon, Sun-Jung; Park, Myung-Sik; Matsuda, Dean K; Choi, Yun Ho

2018-06-04

Sciatic nerve injuries following total hip arthroplasty are disabling complications. Although degrees of injury are variable from neuropraxia to neurotmesis, mechanical irritation of sciatic nerve might be occurred by protruding hardware. This case shows endoscopic decompression for protruded acetabular screw irritating sciatic nerve, the techniques described herein may permit broader arthroscopic/endoscopic applications for management of complications after reconstructive hip surgery. An 80-year-old man complained of severe pain and paresthesias following acetabular component revision surgery. Physical findings included right buttock pain with radiating pain to lower extremity. Radiographs and computed tomography imaging showed that the sharp end of protruded screw invaded greater sciatic foramen anterior to posterior and distal to proximal direction at sciatic notch level. A protruding tip of the acetabular screw at the sciatic notch was decompressed by use of techniques gained from experience performing endoscopic sciatic nerve decompression. The pre-operative pain and paresthesias resolved post-operatively after recovering from anesthesia. This case report describes the first documented endoscopic resection of the tip of the acetabular screw irritating sciatic nerve after total hip arthroplasty. If endoscopic resection of an offending acetabular screw can be performed in a safe and minimally invasive manner, one can envision a future expansion of the role of hip arthroscopic surgery in several complications management after total hip arthroplasty.

Role of hilar resection in the treatment of hilar cholangiocarcinoma.

PubMed

Otani, Kazuhiro; Chijiiwa, Kazuo; Kai, Masahiro; Ohuchida, Jiro; Nagano, Motoaki; Kondo, Kazuhiro

2012-05-01

The aim of this study was to clarify the role of bile duct resection without hepatectomy (hilar resection) in hilar cholangiocarcinoma. We retrospectively compared surgical results for hilar cholangiocarcinoma between 8 patients treated with hilar resection and 21 patients treated with hepatectomy. All hilar resections were performed for Bismuth type I or II tumors with T2 or less lesions, whereas hepatectomy was done for type III or IV tumors excluding one type II tumor. R0 resection was equally achieved in both groups (62.5% in hilar resection group and 76.2% in hepatectomy group, p=0.469) and overall 5-year survival rates were comparable (21.9% vs. 23.6%, p=0.874). With respect to gross tumor appearance, R0 resection was achieved in all patients with papillary tumor in both groups with the excellent 5-year survivals (100% vs. 100%). In patients with nodular and flat tumors, R0 resection was achieved less frequently in the hilar resection vs. hepatectomy group (50% vs. 77.8%) mainly due to failure to clear the proximal ductal margin, resulting in poorer 5-year survival (0% vs. 18.7%). Hilar resection may be indicated for papillary T1 or 2 tumors in Bismuth type I or II cholangiocarcinoma.

Hippocampography Guides Consistent Mesial Resections in Neocortical Temporal Lobe Epilepsy

PubMed Central

Kilbride, Ronan; Simon, Mirela; Eskandar, Emad

2016-01-01

Background. The optimal surgery in lesional neocortical temporal lobe epilepsy is unknown. Hippocampal electrocorticography maximizes seizure freedom by identifying normal-appearing epileptogenic tissue for resection and minimizes neuropsychological deficit by limiting resection to demonstrably epileptogenic tissue. We examined whether standardized hippocampal electrocorticography (hippocampography) guides resection for more consistent hippocampectomy than unguided resection in conventional electrocorticography focused on the lesion. Methods. Retrospective chart reviews any kind of electrocorticography (including hippocampography) as part of combined lesionectomy, anterolateral temporal lobectomy, and hippocampectomy over 8 years . Patients were divided into mesial (i.e., hippocampography) and lateral electrocorticography groups. Primary outcome was deviation from mean hippocampectomy length. Results. Of 26 patients, fourteen underwent hippocampography-guided mesial temporal resection. Hippocampography was associated with 2.6 times more consistent resection. The range of hippocampal resection was 0.7 cm in the mesial group and 1.8 cm in the lateral group (p = 0.01). 86% of mesial group versus 42% of lateral group patients achieved seizure freedom (p = 0.02). Conclusions. By rationally tailoring excision to demonstrably epileptogenic tissue, hippocampography significantly reduces resection variability for more consistent hippocampectomy than unguided resection in conventional electrocorticography. More consistent hippocampal resection may avoid overresection, which poses greater neuropsychological risk, and underresection, which jeopardizes postoperative seizure freedom. PMID:27703809

Ultralow-power all-optical processing of high-speed data signals in deposited silicon waveguides.

PubMed

Wang, Ke-Yao; Petrillo, Keith G; Foster, Mark A; Foster, Amy C

2012-10-22

Utilizing a 6-mm-long hydrogenated amorphous silicon nanowaveguide, we demonstrate error-free (BER < 10(-9)) 160-to-10 Gb/s OTDM demultiplexing using ultralow switching peak powers of 50 mW. This material is deposited at low temperatures enabling a path toward multilayer integration and therefore massive scaling of the number of devices in a single photonic chip.

Using the trans-lamina terminalis route via a pterional approach to resect a retrochiasmatic craniopharyngioma involving the third ventricle.

PubMed

Weil, Alexander G; Robert, Thomas; Alsaiari, Sultan; Obaid, Sami; Bojanowski, Michel W

2016-01-01

Retrochiasmatic craniopharyngiomas involving the anterior third ventricle are challenging to access. Although the pterional approach is a common route for suprasellar lesions, when the craniopharyngioma extends behind the chiasma into the third ventricle, access is even more difficult, and the lamina terminalis may offer a good working window. The translamina terminalis approach provides direct access to the retrochiasmatic portion of the tumor with minimal brain retraction and no manipulation of the visual nerves. In this video, we emphasize the utility of using the lamina terminalis corridor to resect the retrochiasmatic intraventricular portion of a craniopharyngioma. The video can be found here: https://youtu.be/hrLNC0hDKe4 .

Alterations of decision making and underlying neural correlates after resection of a mediofrontal cortical dysplasia: A single case study.

PubMed

Labudda, Kirsten; Brand, Matthias; Mertens, Markus; Ebner, Alois; Markowitsch, Hans J; Woermann, Friedrich G

2010-02-01

We investigated the impact of a congenital prefrontal lesion and its resection on decision making under risk and under ambiguity in a patient with right mediofrontal cortical dysplasia. Both kinds of decision making are normally associated with the medial prefrontal cortex. We additionally studied pre- and postsurgical fMRI activations when processing information relevant for risky decision making. Results indicate selective impairments of ambiguous decision making pre- and postsurgically. Decision making under risk was intact. In contrast to healthy subjects the patient exhibited no activation within the dysplastic anterior cingulate cortex but left-sided orbitofrontal activation on the fMRI task suggesting early reorganization processes.

Prospective analysis of neuropsychological deficits following resection of benign skull base meningiomas.

PubMed

Zweckberger, Klaus; Hallek, Eveline; Vogt, Lidia; Giese, Henrik; Schick, Uta; Unterberg, Andreas W

2017-12-01

OBJECTIVE Resection of skull base tumors is challenging. The introduction of alternative treatment options, such as radiotherapy, has sparked discussion regarding outcome in terms of quality of life and neuropsychological deficits. So far, however, no prospective data are available on this topic. METHODS A total of 58 patients with skull base meningiomas who underwent surgery for the first time were enrolled in this prospective single-center trial. The average age of the patients was 56.4 ± 12.5 years. Seventy-nine percent of the tumors were located within the anterior skull base. Neurological examinations and neuropsychological testing were performed at 3 time points: 1 day prior to surgery (T1), 3-5 months after surgery (T2), and 9-12 months after surgery (T3). The average follow-up duration was 13.8 months. Neuropsychological assessment consisted of quality of life, depression and anxiety, verbal learning and memory, cognitive speed, attention and concentration, figural memory, and visual-motor speed. RESULTS Following surgery, 23% of patients showed transient neurological deficits and 12% showed permanent new neurological deficits with varying grades of manifestation. Postoperative quality of life, however, remained stable and was slightly improved at follow-up examinations at T3 (60.6 ± 21.5 vs 63.6 ± 24.1 points), and there was no observed effect on anxiety and depression. Long-term verbal memory, working memory, and executive functioning were slightly affected within the first months following surgery and appeared to be the most vulnerable to impairment by the tumor or the resection but were stable or improved in the majority of patients at long-term follow-up examinations after 1 year. CONCLUSIONS This report describes the first prospective study of neuropsychological outcomes following resection of skull base meningiomas and, as such, contributes to a better understanding of postoperative impairment in these patients. Despite deterioration in a minority

Prophylactic transanal decompression tube versus non-prophylactic transanal decompression tube for anastomotic leakage prevention in low anterior resection for rectal cancer: a meta-analysis.

PubMed

Yang, Yun; Shu, Ye; Su, Fangyu; Xia, Lin; Duan, Baofeng; Wu, Xiaoting

2017-04-01

Transanal decompression tube (TDT), an alternative intervention believed to have potential equivalent efficacy in reducing anastomotic leakage after rectal cancer surgery and lower complication rates compared to protective stoma, was sporadically applied in some medical centers during recent decade. The objective of this meta-analysis was to evaluate the effect of the TDT in preventing the anastomotic leakage after low anterior resection for rectal cancer. The studies comparing TDT and non-TDT in rectal cancer were researched up to March 22, 2016 without language preference, in databases of PubMed, Web of Science, Cochrane library, International Clinical Trials Registry Platform, and National Clinical Trials Registry. The rates of anastomotic leakage, bleeding, and re-operation were separately calculated and compared between TDT and non-TDT groups using RevMan 5.3. Funnel plots, and Egger's tests were used to evaluate the publication biases of the studies. Two prospective randomized controlled trial studies and five observational cohort studies with 833 participants in TDT group and 939 participants in non-TDT group were finally included in this meta-analysis. The results indicated that the TDT group had lower anastomotic leakage rate than non-TDT group with significant RR (RR 0.44; 95 % CI 0.29-0.66; P < 0.0001) and heterogeneity (I 2  = 33 %; P = 0.18). So did the re-operation rate, with RR (RR 0.16; 95 % CI 0.07-0.37; P < 0.0001) and heterogeneity among the studies (I 2  = 0 %; P = 0.80). There was no significant difference in anastomotic bleeding rates (RR 1.48; 95 % CI 0.79-2.77; P = 0.22) (I 2  = 58 %; P = 0.09). No publication bias was found by Egger's test (anastomotic leakage rate, Pr > |z| = 0.224; re-operation rate, Pr > |z| = 0.425). TDT might be an efficient and economic intervention in preventing anastomotic leakage after rectal cancer surgery.

Natural orifice transgastric endoscopic wedge hepatic resection in an experimental model using an intuitively controlled master and slave transluminal endoscopic robot (MASTER).

PubMed

Phee, S J; Ho, K Y; Lomanto, D; Low, S C; Huynh, V A; Kencana, A P; Yang, K; Sun, Z L; Chung, S C Sydney

2010-09-01

The lack of triangulation of standard endoscopic devices limits the degree of freedom for surgical maneuvers during natural orifice transluminal endoscopic surgery (NOTES). This study explored the feasibility of adapting an intuitively controlled master and slave transluminal endoscopic robot (MASTER) the authors developed to facilitate wedge hepatic resection in NOTES. The MASTER consists of a master controller, a telesurgical workstation, and a slave manipulator that holds two end-effectors: a grasper, and a monopolar electrocautery hook. The master controller is attached to the wrist and fingers of the operator and connected to the manipulator by electrical and wire cables. Movements of the operator are detected and converted into control signals driving the slave manipulator via a tendon-sheath power transmission mechanism allowing nine degrees of freedom. Using this system, wedge hepatic resection was performed through the transgastric route on two female pigs under general anesthesia. Entry into the peritoneal cavity was via a 10-mm incision made on the anterior wall of the stomach by the electrocautery hook. Wedge hepatic resection was performed using the robotic grasper and hook. Hemostasis was achieved with the electrocautery hook. After the procedure, the resected liver tissue was retrieved through the mouth using the grasper. Using the MASTER, transgastric wedge hepatic resection was successfully performed on two pigs with no laparoscopic assistance. The entire procedure took 9.4 min (range, 8.5-10.2 min), with 7.1 min (range, 6-8.2 min) spent on excision of the liver tissue. The robotics-controlled device was able to grasp, retract, and excise the liver specimen successfully in the desired plane. This study demonstrated for the first time that the MASTER could effectively mitigate the technical constraints normally encountered in NOTES procedures. With it, the triangulation of surgical tools and the manipulation of tissue became easy, and wedge hepatic

Biomechanical comparison of anterior cervical plating and combined anterior/lateral mass plating.

PubMed

Adams, M S; Crawford, N R; Chamberlain, R H; Bse; Sonntag, V K; Dickman, C A

2001-01-01

Previous studies showed anterior plates of older design to be inadequate for stabilizing the cervical spine in all loading directions. No studies have investigated enhancement in stability obtained by combining anterior and posterior plates. To determine which modes of loading are stabilized by anterior plating after a cervical burst fracture and to determine whether adding posterior plating further significantly stabilizes the construct. A repeated-measures in vitro biomechanical flexibility experiment was performed to investigate how surgical destabilization and subsequent addition of hardware components alter spinal stability. Six human cadaveric specimens were studied. Angular range of motion (ROM) and neutral zone (NZ) were quantified during flexion, extension, lateral bending, and axial rotation. Nonconstraining, nondestructive torques were applied while recording three-dimensional motion optoelectronically. Specimens were tested intact, destabilized by simulated burst fracture with posterior distraction, plated anteriorly with a unicortical locking system, and plated with a combined anterior/posterior construct. The anterior plate significantly (p<.05) reduced the ROM relative to normal in all modes of loading and significantly reduced the NZ in flexion and extension. Addition of the posterior plates further significantly reduced the ROM in all modes of loading and reduced the NZ in lateral bending. Anterior plating systems are capable of substantially stabilizing the cervical spine in all modes of loading after a burst fracture. The combined approach adds significant stability over anterior plating alone in treating this injury but may be unnecessary clinically. Further study is needed to assess the added clinical benefits of the combined approach and associated risks.

Arthroscopy and the Dramatic Increase in Frequency of Anterior Acromioplasty from 1980 to 2005: An Epidemiologic Study

PubMed Central

Yu, Elizabeth; Cil, Akin; Harmsen, William Scott; Schleck, Cathy; Sperling, John W.; Cofield, Robert H.

2011-01-01

Purpose The purpose of this study is to better understand the utilization of anterior acromioplasty over time – in the absence of rotator cuff repair, to examine the relationship to patient characteristics (age, sex) and types of rotator cuff pathology (inflammation or fibrosis, partial thickness tearing, full thickness tearing undergoing debridement), and to assess the utilization of arthroscopy in this procedure. Methods Using the resources of the Rochester Epidemiology Project, cataloging medical records of residents in Olmsted County, Minnesota, we identified 246 patients who underwent anterior acromioplasty between 1980 and 2005. It has previously been shown that rarely does a resident of Olmsted County undergo an orthopedic procedure at a facility outside the county. Results The incidence of anterior acromioplasty increased over time (p<0.001) with the crude rate of 3.3 per 100,000 in 1980 to 1985 to 19.0 per 100,000 in 2000 to 2005. Sex, age, and types of rotator cuff pathology did not significantly change over the twenty-six year period. There was a dramatic shift from use of the open to the arthroscopic approach over this time period (p<0.001) and a decrease in the concomitant performance of distal clavicle resection (p<0.001). Conclusions The frequency of anterior acromioplasty has dramatically increased over time. Increasing knowledge about this syndrome, including better imaging, has facilitated patient treatment for a stable spectrum of rotator cuff pathology (inflammation or fibrosis, partial thickness tearing, full thickness tearing undergoing debridement), as has the application of endoscopic surgery. PMID:20691562

Should spikes on post-resection ECoG guide pediatric epilepsy surgery?

PubMed

Greiner, Hansel M; Horn, Paul S; Tenney, Jeffrey R; Arya, Ravindra; Jain, Sejal V; Holland, Katherine D; Leach, James L; Miles, Lili; Rose, Douglas F; Fujiwara, Hisako; Mangano, Francesco T

2016-05-01

There is wide variation in clinical practice regarding the role of electrocorticography immediately after resection (post-resection ECoG) for pediatric epilepsy surgery. Results can guide further resection of potentially epileptogenic tissue. We hypothesized that post-resection ECoG spiking represents a biomarker of the epileptogenic zone and predicts seizure outcome in children undergoing epilepsy surgery. We retrospectively identified 124 children with post-resection ECoG performed on the margins of resection. ECoG records were scored in a blinded fashion based on presence of frequent spiking. For patients identified as having additional resection based on clinical post-resection ECoG interpretation, these "second-look" ECoG results were re-reviewed for ongoing discharges or completeness of resection. Frequent spike populations were grouped using a standard scoring system into three ranges: 0.1-0.5Hz, 0.5-1Hz, >1Hz. Seizure outcomes were determined at minimum 12-month followup. Of 124 patients who met inclusion criteria, 60 (48%) had an identified spike population on post-resection ECoG. Thirty (50%) of these had further resection based on clinical interpretation. Overall, good outcome (ILAE 1) was seen in 56/124 (45%). Completeness of resection of spiking (absence of spiking on initial post-resection ECoG or resolution of spiking after further resection) showed a trend toward good outcome (OR 2.03, p=0.099). Patients with completeness of resection had good outcome in 41/80 (51%) of cases; patients with continued spikes had good outcome in 15/44 (35%) of cases. Post-resection ECoG identifies residual epileptogenic tissue in a significant number of children. Lower frequency or absence of discharges on initial recording showed a trend toward good outcome. Completeness of resection demonstrated on final ECoG recording did not show a significant difference in outcome. This suggests that post-resection discharges represent a prognostic marker rather than a remediable

[Three-dimensional finite element modeling and biomechanical simulation for evaluating and improving postoperative internal instrumentation of neck-thoracic vertebral tumor en bloc resection].

PubMed

Qinghua, Zhao; Jipeng, Li; Yongxing, Zhang; He, Liang; Xuepeng, Wang; Peng, Yan; Xiaofeng, Wu

2015-04-07

To employ three-dimensional finite element modeling and biomechanical simulation for evaluating the stability and stress conduction of two postoperative internal fixed modeling-multilevel posterior instrumentation ( MPI) and MPI with anterior instrumentation (MPAI) with neck-thoracic vertebral tumor en bloc resection. Mimics software and computed tomography (CT) images were used to establish the three-dimensional (3D) model of vertebrae C5-T2 and simulated the C7 en bloc vertebral resection for MPI and MPAI modeling. Then the statistics and images were transmitted into the ANSYS finite element system and 20N distribution load (simulating body weight) and applied 1 N · m torque on neutral point for simulating vertebral displacement and stress conduction and distribution of motion mode, i. e. flexion, extension, bending and rotating. With a better stability, the displacement of two adjacent vertebral bodies of MPI and MPAI modeling was less than that of complete vertebral modeling. No significant differences existed between each other. But as for stress shielding effect reduction, MPI was slightly better than MPAI. From biomechanical point of view, two internal instrumentations with neck-thoracic tumor en bloc resection may achieve an excellent stability with no significant differences. But with better stress conduction, MPI is more advantageous in postoperative reconstruction.

Polarization-insensitive ultralow-power second-harmonic generation frequency-resolved optical gating.

PubMed

Miao, Houxun; Weiner, Andrew M; Langrock, Carsten; Roussev, Rostislav V; Fejer, Martin M

2007-04-01

We demonstrate polarization-insensitive ultralow-power second-harmonic generation frequency-resolved optical gating (FROG) measurements with a fiber-pigtailed, aperiodically poled lithium niobate waveguide. By scrambling the polarization much faster than the measurement integration time, we eliminate the impairment that frequency-independent random polarization fluctuations induce in FROG measurements. As a result we are able to retrieve intensity and phase profiles of few hundred femtosecond optical pulses with 50 MHz repetition rates at 5.2 nW coupled average power without control of the input polarization.

a-SiNx:H-based ultra-low power resistive random access memory with tunable Si dangling bond conduction paths

PubMed Central

Jiang, Xiaofan; Ma, Zhongyuan; Xu, Jun; Chen, Kunji; Xu, Ling; Li, Wei; Huang, Xinfan; Feng, Duan

2015-01-01

The realization of ultra-low power Si-based resistive switching memory technology will be a milestone in the development of next generation non-volatile memory. Here we show that a high performance and ultra-low power resistive random access memory (RRAM) based on an Al/a-SiNx:H/p+-Si structure can be achieved by tuning the Si dangling bond conduction paths. We reveal the intrinsic relationship between the Si dangling bonds and the N/Si ratio x for the a-SiNx:H films, which ensures that the programming current can be reduced to less than 1 μA by increasing the value of x. Theoretically calculated current-voltage (I–V ) curves combined with the temperature dependence of the I–V characteristics confirm that, for the low-resistance state (LRS), the Si dangling bond conduction paths obey the trap-assisted tunneling model. In the high-resistance state (HRS), conduction is dominated by either hopping or Poole–Frenkel (P–F) processes. Our introduction of hydrogen in the a-SiNx:H layer provides a new way to control the Si dangling bond conduction paths, and thus opens up a research field for ultra-low power Si-based RRAM. PMID:26508086

Ultralow-power local laser control of the dimer density in alkali-metal vapors through photodesorption

DOE Office of Scientific and Technical Information (OSTI.GOV)

Jha, Pankaj K.; Scully, Marlan O.; Princeton University, Princeton, New Jersey 08544

2012-08-27

Ultralow-power diode-laser radiation is employed to induce photodesorption of cesium from a partially transparent thin-film cesium adsorbate on a solid surface. Using resonant Raman spectroscopy, we demonstrate that this photodesorption process enables an accurate local optical control of the density of dimer molecules in alkali-metal vapors.

Robotic Low Ligation of the Inferior Mesenteric Artery for Rectal Cancer Using the Firefly Technique.

PubMed

Bae, Sung Uk; Min, Byung Soh; Kim, Nam Kyu

2015-07-01

By integrating intraoperative near infrared fluorescence imaging into a robotic system, surgeons can identify the vascular anatomy in real-time with the technical advantages of robotics that is useful for meticulous lymphovascular dissection. Herein, we report our initial experience of robotic low ligation of the inferior mesenteric artery (IMA) with real-time identification of the vascular system for rectal cancer using the Firefly technique. The study group included 11 patients who underwent a robotic total mesorectal excision with preservation of the left colic artery for rectal cancer using the Firefly technique between July 2013 and December 2013. The procedures included five low anterior resections and six ultra-low anterior resections with loop ileostomy. The median total operation time was 327 min (226-490). The low ligation time was 10 min (6-20), and the time interval between indocyanine green injection and division of the sigmoid artery was 5 min (2-8). The estimated blood loss was 200 mL (100-500). The median time to soft diet was 4 days (4-5), and the median length of stay was 7 days (5-9). Three patients developed postoperative complications; one patients developed anal stricture, one developed ileus, and one developed non-complicated intraabdominal fluid collection. The median total number of lymph nodes harvested was 17 (9-29). Robotic low ligation of the IMA with real-time identification of the vascular system for rectal cancer using the Firefly technique is safe and feasible. This technique can allow for precise lymph node dissection along the IMA and facilitate the identification of the left colic branch of the IMA.

Sensitivity of new detection method for ultra-low frequency gravitational waves with pulsar spin-down rate statistics

NASA Astrophysics Data System (ADS)

Yonemaru, Naoyuki; Kumamoto, Hiroki; Takahashi, Keitaro; Kuroyanagi, Sachiko

2018-04-01

A new detection method for ultra-low frequency gravitational waves (GWs) with a frequency much lower than the observational range of pulsar timing arrays (PTAs) was suggested in Yonemaru et al. (2016). In the PTA analysis, ultra-low frequency GWs (≲ 10-10 Hz) which evolve just linearly during the observation time span are absorbed by the pulsar spin-down rates since both have the same effect on the pulse arrival time. Therefore, such GWs cannot be detected by the conventional method of PTAs. However, the bias on the observed spin-down rates depends on relative direction of a pulsar and GW source and shows a quadrupole pattern in the sky. Thus, if we divide the pulsars according to the position in the sky and see the difference in the statistics of the spin-down rates, ultra-low frequency GWs from a single source can be detected. In this paper, we evaluate the potential of this method by Monte-Carlo simulations and estimate the sensitivity, considering only the "Earth term" while the "pulsar term" acts like random noise for GW frequencies 10-13 - 10-10 Hz. We find that with 3,000 milli-second pulsars, which are expected to be discovered by a future survey with the Square Kilometre Array, GWs with the derivative of amplitude of about 3 × 10^{-19} {s}^{-1} can in principle be detected. Implications for possible supermassive binary black holes in Sgr* and M87 are also given.

Detection of changes in bone quality of osteoporotic model induced by sciatic nerve resection by using Raman spectroscopy

NASA Astrophysics Data System (ADS)

Ishimaru, Yasumitsu; Oshima, Yusuke; Imai, Yuuki; Iimura, Tadahiro; Takanezawa, Sota; Hino, Kazunori; Miura, Hiromasa

2018-02-01

To detect the bone quality loss in osteoporosis, we performed Raman spectroscopic analysis of sciatic nerve resection (NX) mice. Eight months after surgery, lower limbs were collected from the mice and fixed with 70% ethanol. Raman spectra of anterior cortical surface of the proximal tibia at 5 points in each bone were measured by RENISHAW inVia Raman Microscope. Excitation wave length was 785 nm. We also performed DXA and micro CT measurement to confirm the bone mineral density and bone microstructure in the osteoporotic model induced by sciatic nerve resection. In the result of Raman spectroscopy, we detected changes of Raman peak intensity ratio in carbonate/phosphate, mineral/combined proline and hydroxyproline and mineral/phenylalanine. In addition, in the result of micro CT, we found significant changes in VOX BV/TV, Trabecular number, thickness, cancellous bone mineral density, cortical thickness and cortical bone mineral density. The results suggest that not only the bone mineral density but also bone quality reduced in the NX mice. We conclude that Raman spectroscopy is a useful for bone quality assessment as a complementary technique for conventional diagnostics.

The Relationship of Amount of Resection and Time for Recovery of Bell’s Phenomenon after Levator Resection in Congenital Ptosis

PubMed Central

Goel, Ruchi; Kishore, Divya; Nagpal, Smriti; Jain, Sparshi; Agarwal, Tushar

2017-01-01

Background: Recovery of Bell`s phenomenon after levator resection is unpredicatable. Delayed recovery can result in vision threatening corneal complications. Aim: To study the variability of Bell’s phenomenon and time taken for its recovery following levator resection for blepharoptosis and to correlate it with the amount of resection. Methods: A prospective observational study was conducted on 32 eyes of 32 patients diagnosed as unilateral simple congenital blepharoptosis who underwent levator resection at a tertiary care center between July 2013 and May 2015. Patients were followed up for 5 months and correction of ptosis, type of Bell`s, duration of Bell`s recovery and complications were noted. Results: The study group ranged from 16-25 years with 15:17 male: female ratio. There were 9 mild, 16 moderate and 7 severe ptosis. Satisfactory correction was achieved in all cases. Good Bell`s recovery occurred in 13 eyes on first post-op day, in 2-14 days in 19 eyes and 28 days in 1 eye. Inverse Bell`s was noted along with lid oedema and ecchymosis in 2 patients. Large resections (23-26mm) were associated with poor Bell`s on the first postoperative day (p=0.027, Fisher`s exact test). However, the duration required for recovery of Bell`s phenomenon did not show any significant difference with the amount of resection. (p=0.248, Mann Whitney test). Larger resections resulted in greater lagophthalmos (correlation=0.830, p<0.0001). Patients with recovery of Bell`s delayed for more than 7 days were associated with greater number of complications (p=0.001 Fisher`s Exact Test). Conclusion: Close monitoring for Bell`s recovery is required following levator resection. PMID:28584563

Effect of Laparoscopic-Assisted Resection vs Open Resection on Pathological Outcomes in Rectal Cancer: The ALaCaRT Randomized Clinical Trial.

PubMed

Stevenson, Andrew R L; Solomon, Michael J; Lumley, John W; Hewett, Peter; Clouston, Andrew D; Gebski, Val J; Davies, Lucy; Wilson, Kate; Hague, Wendy; Simes, John

2015-10-06

Laparoscopic procedures are generally thought to have better outcomes than open procedures. Because of anatomical constraints, laparoscopic rectal resection may not be better because of limitations in performing an adequate cancer resection. To determine whether laparoscopic resection is noninferior to open rectal cancer resection for adequacy of cancer clearance. Randomized, noninferiority, phase 3 trial (Australasian Laparoscopic Cancer of the Rectum; ALaCaRT) conducted between March 2010 and November 2014. Twenty-six accredited surgeons from 24 sites in Australia and New Zealand randomized 475 patients with T1-T3 rectal adenocarcinoma less than 15 cm from the anal verge. Open laparotomy and rectal resection (n = 237) or laparoscopic rectal resection (n = 238). The primary end point was a composite of oncological factors indicating an adequate surgical resection, with a noninferiority boundary of Δ = -8%. Successful resection was defined as meeting all the following criteria: (1) complete total mesorectal excision, (2) a clear circumferential margin (≥1 mm), and (3) a clear distal resection margin (≥1 mm). Pathologists used standardized reporting and were blinded to the method of surgery. A successful resection was achieved in 194 patients (82%) in the laparoscopic surgery group and 208 patients (89%) in the open surgery group (risk difference of -7.0% [95% CI, -12.4% to ∞]; P = .38 for noninferiority). The circumferential resection margin was clear in 222 patients (93%) in the laparoscopic surgery group and in 228 patients (97%) in the open surgery group (risk difference of -3.7% [95% CI, -7.6% to 0.1%]; P = .06), the distal margin was clear in 236 patients (99%) in the laparoscopic surgery group and in 234 patients (99%) in the open surgery group (risk difference of -0.4% [95% CI, -1.8% to 1.0%]; P = .67), and total mesorectal excision was complete in 206 patients (87%) in the laparoscopic surgery group and 216 patients (92%) in

Labral Reattachment in Femoroacetabular Impingement Surgery Results in Increased 10-year Survivorship Compared With Resection.

PubMed

Anwander, Helen; Siebenrock, Klaus A; Tannast, Moritz; Steppacher, Simon D

2017-04-01

Since the importance of an intact labrum for normal hip function has been shown, labral reattachment has become the standard method for open or arthroscopic treatment of hips with femoroacetabular impingement (FAI). However, no long-term clinical results exist evaluating the effect of labral reattachment. A 2-year followup comparing open surgical treatment of FAI with labral resection versus reattachment was previously performed at our clinic. The goal of this study was to report a concise followup of these patients at a minimum of 10 years. We asked if patients undergoing surgical hip dislocation for the treatment of mixed-type FAI with labral reattachment compared with labral resection had (1) improved hip pain and function based on the Merle d'Aubigné-Postel score; and (2) improved survival at 10-year followup. Between June 1999 and July 2002, we performed surgical hip dislocation with femoral neck osteoplasty and acetabular rim trimming in 52 patients (60 hips) with mixed-type FAI. In the first 20 patients (25 hips) until June 2001, a torn labrum or a detached labrum in the area of acetabular rim resection was resected. In the next 32 patients (35 hips), reattachment of the labrum was performed. The same indications were used to perform both procedures during the periods in question. Of the 20 patients (25 hips) in the first group, 19 patients (95%) (24 hips [96%]) were available for clinical and/or radiographic followup at a minimum of 10 years (mean, 13 years; range, 12-14 years). Of the 32 patients (35 hips) in the second group, 29 patients (91%) (32 hips [91%]) were available for clinical and/or radiographic followup at a minimum of 10 years (mean, 12 years; range, 10-13 years). We used the anterior impingement test to assess pain. Function was assessed using the Merle d'Aubigné- Postel score and ROM. Survivorship calculation was performed using the method of Kaplan-Meier with failure defined as conversion to THA, progression of osteoarthritis (of one

Desmoid Fibromatosis of the Abdominal Wall: Surgical Resection and Reconstruction with Biological Matrix Egis®

PubMed Central

Tropea, Saveria; Mocellin, Simone; Stramare, Roberto; Bonavina, Maria Giuseppina; Rossi, Carlo Riccardo; Rastrelli, Marco

2017-01-01

Desmoid tumor is a rare monoclonal fibroblast proliferation that is regarded as benign. The clinical management of desmoid tumors is very complex and requires a multidisciplinary approach because of the unpredictable disease course. For those cases localized in the anterior abdominal wall, symptomatic and unresponsive to medical treatment, radical resection and reconstruction with a prosthetic device are indicated. We present here a case of desmoid fibromatosis of the left anterolateral abdominal wall with a marked increase of the mass that required a large excision followed by reconstruction with biological matrix. The fact that it can be incorporated in patient tissue without a fibrotic response and that it can resist future infections, together with a very competetive price, made the new collagen matrix Egis® our first choice. PMID:28413398

A compositional origin to ultralow-velocity zones

NASA Astrophysics Data System (ADS)

Brown, Samuel P.; Thorne, Michael S.; Miyagi, Lowell; Rost, Sebastian

2015-02-01

We analyzed vertical component short-period ScP waveforms for 26 earthquakes occurring in the Tonga-Fiji trench recorded at the Alice Springs Array in central Australia. These waveforms show strong precursory and postcursory seismic arrivals consistent with ultralow-velocity zone (ULVZ) layering beneath the Coral Sea. We used the Viterbi sparse spike detection method to measure differential travel times and amplitudes of the postcursor arrival ScSP and the precursor arrival SPcP relative to ScP. We compare our measurements to a database of 340,000 synthetic seismograms finding that these data are best fit by a ULVZ model with an S wave velocity reduction of 24%, a P wave velocity reduction of 23%, a thickness of 8.5 km, and a density increase of 6%. This 1:1 VS:VP velocity decrease is commensurate with a ULVZ compositional origin and is most consistent with highly iron enriched ferropericlase.

Sequential resection of lung metastasis following partial hepatectomy for colorectal cancer.

PubMed

Ike, H; Shimada, H; Togo, S; Yamaguchi, S; Ichikawa, Y; Tanaka, K

2002-09-01

Multiple organ metastases from colorectal carcinoma may be considered incurable, but long survival after both liver and lung resection for metastases has been reported. A retrospective analysis of 48 patients who underwent lung resection for metastatic colorectal cancer between 1992 and 1999 was undertaken. Twenty-seven patients had lung metastasis alone, 15 had previous partial hepatectomy, and six had previous resection of local or lymph node recurrence. The relationship of clinical variables to survival was assessed. Survival was calculated from the time of first pulmonary resection. Five-year survival rates after resection of lung metastasis were 73 per cent in patients without preceding recurrence, 50 per cent following previous partial hepatectomy and zero after resection of previous local recurrence. Independent prognostic variables that significantly affected survival after thoracotomy were primary tumour histology and type of preceding recurrence. There was no significant difference in survival after lung resection between patients who had sequential liver and lung resection versus those who had lung resection alone. Sequential lung resection after partial hepatectomy for metastatic colorectal cancer may lead to long-term survival.

Seizure outcomes in non-resective epilepsy surgery: An update

PubMed Central

Englot, Dario J.; Birk, Harjus; Chang, Edward F.

2016-01-01

In approximately 30% of patients with epilepsy, seizures are refractory to medical therapy, leading to significant morbidity and increased mortality. Substantial evidence has demonstrated the benefit of surgical resection in patients with drug-resistant focal epilepsy, and in the present journal, we recently reviewed seizure outcomes in resective epilepsy surgery. However, not all patients are candidates for or amenable to open surgical resection for epilepsy. Fortunately, several non-resective surgical options are now available at various epilepsy centers, including novel therapies which have been pioneered in recent years. Ablative procedures such as stereotactic laser ablation and stereotactic radiosurgery offer minimally invasive alternatives to open surgery with relatively favorable seizure outcomes, particularly in patients with mesial temporal lobe epilepsy. For certain individuals who are not candidates for ablation or resection, palliative neuromodulation procedures such as vagus nerve stimulation, deep brain stimulation, or responsive neurostimulation may result in a significant decrease in seizure frequency and improved quality of life. Finally, disconnection procedures such as multiple subpial transections and corpus callosotomy continue to play a role in select patients with an eloquent epileptogenic zone or intractable atonic seizures, respectively. Overall, open surgical resection remains the gold standard treatment for drug-resistant epilepsy, although it is significantly under-utilized. While non-resective epilepsy procedures have not replaced the need for resection, there is hope that these additional surgical options will increase the number of patients who receive treatment for this devastating disorder - particularly individuals who are not candidates for or who have failed resection. PMID:27206422

Hilar cholangiocarcinoma: controversies on the extent of surgical resection aiming at cure.

PubMed

Xiang, Shuai; Lau, Wan Yee; Chen, Xiao-ping

2015-02-01

Hilar cholangiocarcinoma is the most common malignant tumor affecting the extrahepatic bile duct. Surgical treatment offers the only possibility of cure, and it requires removal of all tumoral tissues with adequate resection margins. The aims of this review are to summarize the findings and to discuss the controversies on the extent of surgical resection aiming at cure for hilar cholangiocarcinoma. The English medical literatures on hilar cholangiocarcinoma were studied to review on the relevance of adequate resection margins, routine caudate lobe resection, extent of liver resection, and combined vascular resection on perioperative and long-term survival outcomes of patients with resectable hilar cholangiocarcinoma. Complete resection of tumor represents the most important prognostic factor of long-term survival for hilar cholangiocarcinoma. The primary aim of surgery is to achieve R0 resection. When R1 resection is shown intraoperatively, further resection is recommended. Combined hepatic resection is now generally accepted as a standard procedure even for Bismuth type I/II tumors. Routine caudate lobe resection is also advocated for cure. The extent of hepatic resection remains controversial. Most surgeons recommend major hepatic resection. However, minor hepatic resection has also been advocated in most patients. The decision to carry out right- or left-sided hepatectomy is made according to the predominant site of the lesion. Portal vein resection should be considered when its involvement by tumor is suspected. The curative treatment of hilar cholangiocarcinoma remains challenging. Advances in hepatobiliary techniques have improved the perioperative and long-term survival outcomes of this tumor.

Hepatic Resection for Colorectal Liver Metastases: A Cost-Effectiveness Analysis

PubMed Central

Beard, Stephen M.; Holmes, Michael; Price, Charles; Majeed, Ali W.

2000-01-01

Objective To analyze the cost-effectiveness of resection for liver metastases compared with standard nonsurgical cytotoxic treatment. Summary Background Data The efficacy of hepatic resection for metastases from colorectal cancer has been debated, despite reported 5-year survival rates of 20% to 40%. Resection is confined to specialized centers and is not widely available, perhaps because of lack of appropriate expertise, resources, or awareness of its efficacy. The cost-effectiveness of resection is important from the perspective of managed care in the United States and for the commissioning of health services in the United Kingdom. Methods A simple decision-based model was developed to evaluate the marginal costs and health benefits of hepatic resection. Estimates of resectability for liver metastases were taken from UK-reported case series data. The results of 100 hepatic resections conducted in Sheffield from 1997 to 1999 were used for the cost calculation of liver resection. Survival data from published series of resections were compiled to estimate the incremental cost per life-year gained (LYG) because of the short period of follow-up in the Sheffield series. Results Hepatic resection for colorectal liver metastases provides an estimated marginal benefit of 1.6 life-years (undiscounted) at a marginal cost of £6,742. If 17% of patients have only palliative resections, the overall cost per LYG is approximately £5,236 (£5,985 with discounted benefits). If potential benefits are extended to include 20-year survival rates, these figures fall to approximately £1,821 (£2,793 with discounted benefits). Further univariate sensitivity analysis of key model parameters showed the cost per LYG to be consistently less than £15,000. Conclusion In this model, hepatic resection appears highly cost-effective compared with nonsurgical treatments for colorectal-related liver metastases. PMID:11088071

Ultralow-threshold microcavity Raman laser on a microelectronic chip

NASA Astrophysics Data System (ADS)

Kippenberg, T. J.; Spillane, S. M.; Armani, D. K.; Vahala, K. J.

2004-06-01

Using ultrahigh-Q toroid microcavities on a chip, we demonstrate a monolithic microcavity Raman laser. Cavity photon lifetimes in excess of 100 ns combined with mode volumes typically of less than 1000 µm^3 significantly reduce the threshold for stimulated Raman scattering. In conjunction with the high ideality of a tapered optical fiber coupling junction, stimulated Raman lasing is observed at an ultralow threshold (as low as 74 µW of fiber-launched power at 1550 nm) with high efficiency (up to 45% at the critical coupling point) in good agreement with theoretical modeling. Equally important, the wafer-scale nature of these devices should permit integration with other photonic, mechanical, or electrical functionality on a chip.

Ultralow-threshold microcavity Raman laser on a microelectronic chip.

PubMed

Kippenberg, T J; Spillane, S M; Armani, D K; Vahala, K J

2004-06-01

Using ultrahigh-Q toroid microcavities on a chip, we demonstrate a monolithic microcavity Raman laser. Cavity photon lifetimes in excess of 100 ns combined with mode volumes typically of less than 1000 (microm)3 significantly reduce the threshold for stimulated Raman scattering. In conjunction with the high ideality of a tapered optical fiber coupling junction, stimulated Raman lasing is observed at an ultralow threshold (as low as 74 microW of fiber-launched power at 1550 nm) with high efficiency (up to 45% at the critical coupling point) in good agreement with theoretical modeling. Equally important, the wafer-scale nature of these devices should permit integration with other photonic, mechanical, or electrical functionality on a chip.

Study of ultra-low emittance design for Spear3 using longitudinal gradient dipole

DOE Office of Scientific and Technical Information (OSTI.GOV)

Wang, M. -H.; Huang, X.; Safranek, J.

2015-09-24

Since its 2003 construction, the SPEAR3 synchrotron light source at SLAC has continuously improved its performance by raising beam current, top-off injection, and smaller emittance. This makes SPEAR3 one of the most productive light sources in the world. Now to further enhance the performance of SPEAR3, we are looking into the possibility of converting SPEAR3 to an ultra-low emittance storage ring within its site constraint.

Treatment of Intravenous Leiomyomatosis with Cardiac Extension following Incomplete Resection.

PubMed

Doyle, Mathew P; Li, Annette; Villanueva, Claudia I; Peeceeyen, Sheen C S; Cooper, Michael G; Hanel, Kevin C; Fermanis, Gary G; Robertson, Greg

2015-01-01

Aim. Intravenous leiomyomatosis (IVL) with cardiac extension (CE) is a rare variant of benign uterine leiomyoma. Incomplete resection has a recurrence rate of over 30%. Different hormonal treatments have been described following incomplete resection; however no standard therapy currently exists. We review the literature for medical treatments options following incomplete resection of IVL with CE. Methods. Electronic databases were searched for all studies reporting IVL with CE. These studies were then searched for reports of patients with inoperable or incomplete resection and any further medical treatments. Our database was searched for patients with medical therapy following incomplete resection of IVL with CE and their results were included. Results. All studies were either case reports or case series. Five literature reviews confirm that surgery is the only treatment to achieve cure. The uses of progesterone, estrogen modulation, gonadotropin-releasing hormone antagonism, and aromatase inhibition have been described following incomplete resection. Currently no studies have reviewed the outcomes of these treatments. Conclusions. Complete surgical resection is the only means of cure for IVL with CE, while multiple hormonal therapies have been used with varying results following incomplete resection. Aromatase inhibitors are the only reported treatment to prevent tumor progression or recurrence in patients with incompletely resected IVL with CE.

Treatment of Intravenous Leiomyomatosis with Cardiac Extension following Incomplete Resection

PubMed Central

Doyle, Mathew P.; Li, Annette; Villanueva, Claudia I.; Peeceeyen, Sheen C. S.; Cooper, Michael G.; Hanel, Kevin C.; Fermanis, Gary G.; Robertson, Greg

2015-01-01

Aim. Intravenous leiomyomatosis (IVL) with cardiac extension (CE) is a rare variant of benign uterine leiomyoma. Incomplete resection has a recurrence rate of over 30%. Different hormonal treatments have been described following incomplete resection; however no standard therapy currently exists. We review the literature for medical treatments options following incomplete resection of IVL with CE. Methods. Electronic databases were searched for all studies reporting IVL with CE. These studies were then searched for reports of patients with inoperable or incomplete resection and any further medical treatments. Our database was searched for patients with medical therapy following incomplete resection of IVL with CE and their results were included. Results. All studies were either case reports or case series. Five literature reviews confirm that surgery is the only treatment to achieve cure. The uses of progesterone, estrogen modulation, gonadotropin-releasing hormone antagonism, and aromatase inhibition have been described following incomplete resection. Currently no studies have reviewed the outcomes of these treatments. Conclusions. Complete surgical resection is the only means of cure for IVL with CE, while multiple hormonal therapies have been used with varying results following incomplete resection. Aromatase inhibitors are the only reported treatment to prevent tumor progression or recurrence in patients with incompletely resected IVL with CE. PMID:26783463

Determinants of survival after liver resection for metastatic colorectal carcinoma.

PubMed

Parau, Angela; Todor, Nicolae; Vlad, Liviu

2015-01-01

Prognostic factors for survival after liver resection for metastatic colorectal cancer identified up to date are quite inconsistent with a great inter-study variability. In this study we aimed to identify predictors of outcome in our patient population. A series of 70 consecutive patients from the oncological hepatobiliary database, who had undergone curative hepatic surgical resection for hepatic metastases of colorectal origin, operated between 2006 and 2011, were identified. At 44.6 months (range 13.7-73), 30 of 70 patients (42.85%) were alive. Patient demographics, primary tumor and liver tumor factors, operative factors, pathologic findings, recurrence patterns, disease-free survival (DFS), overall survival (OS) and cancer-specific survival (CSS) were analyzed. Clinicopathologic variables were tested using univariate and multivariate analyses. The 3-year CSS after first hepatic resection was 54%. Median CSS survival after first hepatic resection was 40.2 months. Median CSS after second hepatic resection was 24.2 months. The 3-year DFS after first hepatic resection was 14%. Median disease free survival after first hepatic resection was 18 months. The 3-year DFS after second hepatic resection was 27% and median DFS after second hepatic resection 12 months. The 30-day mortality and morbidity rate after first hepatic resection was 5.71% and 12.78%, respectively. In univariate analysis CSS was significantly reduced for the following factors: age >53 years, advanced T stage of primary tumor, moderately- poorly differentiated tumor, positive and narrow resection margin, preoperative CEA level >30 ng/ml, DFS <18 months. Perioperative chemotherapy related to metastasectomy showed a trend in improving CSS (p=0.07). Perioperative chemotherapy improved DFS in a statistically significant way (p=0.03). Perioperative chemotherapy and achievement of resection margins beyond 1 mm were the major determinants of both CSS and DFS after first liver resection in multivariate

Bone graft options for spinal fusion following resection of spinal column tumors: systematic review and meta-analysis.

PubMed

Elder, Benjamin D; Ishida, Wataru; Goodwin, C Rory; Bydon, Ali; Gokaslan, Ziya L; Sciubba, Daniel M; Wolinsky, Jean-Paul; Witham, Timothy F

2017-01-01

OBJECTIVE With the advent of new adjunctive therapy, the overall survival of patients harboring spinal column tumors has improved. However, there is limited knowledge regarding the optimal bone graft options following resection of spinal column tumors, due to their relative rarity and because fusion outcomes in this cohort are affected by various factors, such as radiation therapy (RT) and chemotherapy. Furthermore, bone graft options are often limited following tumor resection because the use of local bone grafts and bone morphogenetic proteins (BMPs) are usually avoided in light of microscopic infiltration of tumors into local bone and potential carcinogenicity of BMP. The objective of this study was to review and meta-analyze the relevant clinical literature to provide further clinical insight regarding bone graft options. METHODS A web-based MEDLINE search was conducted in accordance with preferred reporting items for systematic review and meta-analysis (PRISMA) guidelines, which yielded 27 articles with 383 patients. Information on baseline characteristics, tumor histology, adjunctive treatments, reconstruction methods, bone graft options, fusion rates, and time to fusion were collected. Pooled fusion rates (PFRs) and I 2 values were calculated in meta-analysis. Meta-regression analyses were also performed if each variable appeared to affect fusion outcomes. Furthermore, data on 272 individual patients were available, which were additionally reviewed and statistically analyzed. RESULTS Overall, fusion rates varied widely from 36.0% to 100.0% due to both inter- and intrastudy heterogeneity, with a PFR of 85.7% (I 2 = 36.4). The studies in which cages were filled with morselized iliac crest autogenic bone graft (ICABG) and/or other bone graft options were used for anterior fusion showed a significantly higher PFR of 92.8, compared with the other studies (83.3%, p = 0.04). In per-patient analysis, anterior plus posterior fusion resulted in a higher fusion rate

Trans-lamina terminalis approach to third ventricle using supraorbital craniotomy: technique description and literature review for outcome comparison with anterior, lateral and trans-sphenoidal corridors.

PubMed

Krishna, V; Blaker, B; Kosnik, L; Patel, S; Vandergrift, W

2011-10-01

The trans-lamina terminalis approach has been described to remove third ventricular tumors. Various surgical corridors for this approach include anterior (via bifrontal craniotomy), anterolateral (via supra-orbital craniotomy), lateral (via pterional craniotomy) and trans-sphenoidal corridors. Supra-orbital craniotomy offers a minimally invasive access for resection of third ventricular tumors. The trans-lamina terminalis technique through a supra-orbital craniotomy is described. Also, a literature review of clinical outcome data was performed for the comparison of different surgical corridors (anterior, antero-lateral, lateral, and trans-sphenoidal). The operative steps and anatomic landmarks for supra-orbital craniotomy are discussed, along with 3 representative cases and respective outcomes. Gross total resection was achieved in 2 patients, and one patient required reoperation for recurrence. Based on the current literature, the clinical outcomes after supra-orbital craniotomy for trans-lamina terminalis approach are comparable to other surgical corridors. The supra-orbital craniotomy for trans-lamina terminalis approach is a valid surgical choice for third ventricular tumors. The major strengths of this approach include minimal brain retraction and direct end-on view; however, the long working distance is a major limitation. The clinical outcomes are comparable to other surgical corridors. Sound understanding of major strengths, limitations, and strategies for complication avoidance is necessary for its safe and effective application. © Georg Thieme Verlag KG Stuttgart · New York.

Highly-Ordered 3D Vertical Resistive Switching Memory Arrays with Ultralow Power Consumption and Ultrahigh Density.

PubMed

Al-Haddad, Ahmed; Wang, Chengliang; Qi, Haoyuan; Grote, Fabian; Wen, Liaoyong; Bernhard, Jörg; Vellacheri, Ranjith; Tarish, Samar; Nabi, Ghulam; Kaiser, Ute; Lei, Yong

2016-09-07

Resistive switching random access memories (RRAM) have attracted great scientific and industrial attention for next generation data storage because of their advantages of nonvolatile properties, high density, low power consumption, fast writing/erasing speed, good endurance, and simple and small operation system. Here, by using a template-assisted technique, we demonstrate a three-dimensional highly ordered vertical RRAM device array with density as high as that of the nanopores of the template (10(8)-10(9) cm(-2)), which can also be fabricated in large area. The high crystallinity of the materials, the large contact area and the intimate semiconductor/electrode interface (3 nm interfacial layer) make the ultralow voltage operation (millivolt magnitude) and ultralow power consumption (picowatt) possible. Our procedure for fabrication of the nanodevice arrays in large area can be used for producing many other different materials and such three-dimensional electronic device arrays with the capability to adjust the device densities can be extended to other applications of the next generation nanodevice technology.

Ultralow-threshold laser and blue shift cooperative luminescence in a Yb{sup 3+} doped silica microsphere

DOE Office of Scientific and Technical Information (OSTI.GOV)

Huang, Yantang, E-mail: g@fzu.edu.cn; Huang, Yu; Zhang, Peijin

2014-02-15

An experimental investigation on ultralow threshold laser and blue shift cooperative luminescence (CL) in a Yb{sup 3+} doped silica microsphere (YDSM) with continuous-wave 976 nm laser diode pumping is reported. The experimental results show that the YDSM emits laser oscillation with ultralow threshold of 2.62 μW, and the laser spectrum is modulated by the microsphere morphology characteristics. In addition, blue emission of YDSM is also observed with the increase of pump power, which is supposed to be generated by CL of excited Yb ion-pairs with the absorption of 976 nm photons and Si-O vibration phonons, and the process is explainedmore » with an energy level diagram. This property of the blue shift CL with phonons absorption in the Yb{sup 3+}doped microcavity makes it attractive for the application of laser cooling based on anti-Stokes fluorescence emission, if the Yb{sup 3+}doped microcavity made from with low phonon energy host materials.« less

3D-printing aided resection of intratracheal adenoid cystic carcinoma and mediastinal mature cystic teratoma in a 26-year-old female: a case report.

PubMed

Lu, Di; Feng, Siyang; Liu, Xiguang; Dong, Xiaoying; Li, Mei; Wu, Hua; Ren, Pengfei; Diao, Dingwei; Cai, Kaican

2018-02-01

Complete resection remains the ideal treatment for most patients with primary intratracheal tumors. Due to the limit in the resection length, the localization of the tumor during the surgery could be rather difficult if it hasn't invaded out of the trachea, which might be more difficult when there's another tumor in the anterior mediastinum. A 26-year-old woman with intratracheal adenoid cystic carcinoma (ACC) presented with dyspnea. CT scan revealed not only an ACC without extension out of trachea, but also a mediastinal teratoma (MT) near aorta, making the operation much more complicated than usual. To solve this problem, 3D-printing was applied for facilitating surgery plan making and intraoperative locating of ACC. And as we expected, the operation went successfully and the patient achieved full recovery without complications. To the best of our knowledge, the case of both intratracheal ACC and MT in one patient has not been previously reported.

Finite element analysis of lordosis restoration with anterior longitudinal ligament release and lateral hyperlordotic cage placement.

PubMed

Uribe, Juan S; Harris, Jeffrey E; Beckman, J M; Turner, Alexander W L; Mundis, Gregory M; Akbarnia, Behrooz A

2015-04-01

Restoring sagittal alignment is an important factor in the treatment of spinal deformities. Recent investigations have determined that releasing the anterior longitudinal ligament (ALL) and placing hyperlordotic cages can increase lordosis, while minimizing need for 3 column osteotomies. The influences of parameters such as cage height and angle have not been determined. Finite element analysis was employed to assess the extent of lordosis achievable after placement of different sized lordotic cages. A 3-dimensional model of a L3-4 segment was used. Disc distraction was simulated by inserting interbody cages mid-body in the disc space. Analyses were performed in the following conditions: (1) intact, (2) ALL release, (3) ALL release + facetectomy, and (4) ALL release + posterior column osteotomy. Changes in segmental lordosis, disc height, foraminal height, and foraminal area were measured. After ALL resection and insertion of hyperlordotic cages, lordosis was increased in all cases. The lordosis achieved by the shorter cages was less due to posterior disc height maintained by the facet joints. A facetectomy increased segmental lordosis, but led to contact between the spinous processes. For some configurations, a posterior column osteotomy was required if the end goal was to match cage angle to intradiscal angle. Increased segmental lumbar lordosis is achievable with hyperlordotic cages after ALL resection. Increased cage height tended to increase the amount of lordosis achieved, although in some cases additional posterior bone resection was required to maximize lordosis. Further studies are needed to evaluate the impact on regional lumbar lordosis.

Anterior tibial stress fractures treated with anterior tension band plating in high-performance athletes.

PubMed

Cruz, Alexandre Santa; de Hollanda, João Paris Buarque; Duarte, Aires; Hungria Neto, José Soares

2013-06-01

The non-surgical treatment of anterior tibial cortex stress fractures requires long periods of abstention from sports activities and often results in non-union. Many different surgical techniques have already been previously described to treat these fractures, but there is no consensus on the best treatment. We describe the outcome of treatment using anterior tibial tension band plating in three high-performance athletes (4 legs) with anterior tibial cortex stress fractures. Tibial osteosynthesis with a 3.5-mm locking compression plate in the anterolateral aspect of the tibia was performed in all patients diagnosed with anterior tibial stress fracture after September 2010 at Santa Casa Hospital. All of the fractures were consolidated within a period of 3 months after surgery, allowing for an early return to pre-injury levels of competitive sports activity. There were no infection, non-union, malunion or anterior knee pain complications. Anterior tibial tension band plating leads to prompt fracture consolidation and is a good alternative for the treatment of anterior tibial cortex stress fractures. Bone grafts were shown to be unnecessary.

Anterior ankle arthroscopy, distraction or dorsiflexion?

PubMed

de Leeuw, Peter A J; Golanó, Pau; Clavero, Joan A; van Dijk, C Niek

2010-05-01

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7-1.5) and 0.7 cm (range 0.5-0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy.

Anterior ankle arthroscopy, distraction or dorsiflexion?

PubMed Central

Golanó, Pau; Clavero, Joan A.; van Dijk, C. Niek

2010-01-01

Anterior ankle arthroscopy can basically be performed by two different methods; the dorsiflexion- or distraction method. The objective of this study was to determine the size of the anterior working area for both the dorsiflexion and distraction method. The anterior working area is anteriorly limited by the overlying anatomy which includes the neurovascular bundle. We hypothesize that in ankle dorsiflexion the anterior neurovascular bundle will move away anteriorly from the ankle joint, whereas in ankle distraction the anterior neurovascular bundle is pulled tight towards the joint, thereby decreasing the safe anterior working area. Six fresh frozen ankle specimens, amputated above the knee, were scanned with computed tomography. Prior to scanning the anterior tibial artery was injected with contrast fluid and subsequently each ankle was scanned both in ankle dorsiflexion and in distraction. A special device was developed to reproducibly obtain ankle dorsiflexion and distraction in the computed tomography scanner. The distance between the anterior border of the inferior tibial articular facet and the posterior border of the anterior tibial artery was measured. The median distance from the anterior border of the inferior tibial articular facet to the posterior border of the anterior tibial artery in ankle dorsiflexion and distraction was 0.9 cm (range 0.7–1.5) and 0.7 cm (range 0.5–0.8), respectively. The distance in ankle dorsiflexion significantly exceeded the distance in ankle distraction (P = 0.03). The current study shows a significantly increased distance between the anterior distal tibia and the overlying anterior neurovascular bundle with the ankle in a slightly dorsiflexed position as compared to the distracted ankle position. We thereby conclude that the distracted ankle position puts the neurovascular structures more at risk for iatrogenic damage when performing anterior ankle arthroscopy. PMID:20217392

Bronchovascular versus bronchial sleeve resection for central lung tumors.

PubMed

Lausberg, Henning F; Graeter, Thomas P; Tscholl, Dietmar; Wendler, Olaf; Schäfers, Hans-Joachim

2005-04-01

Pneumonectomy has traditionally been the treatment of choice for central lung tumors. Bronchial sleeve resections are increasingly considered as a reasonable alternative. For tumor involvement of both central airways and pulmonary artery, bronchovascular sleeve resections are possible, but considered to be technically demanding and associated with a higher perioperative risk. In addition, their role as adequate oncologic treatment for lung cancer is unclear. We have compared the early and long-term results of bronchovascular sleeve resection with those of bronchial sleeve resection and pneumonectomy. We retrospectively analyzed all patients who underwent bronchial sleeve resection (group I, n = 104), bronchovascular sleeve resection (group II, n = 67), and pneumonectomy (group III, n = 63) for central lung cancer in our institution. The groups were comparable regarding demographics and tumor, node, and metastasis (TNM) stage. Early mortality was 1.9% in group I, 1.5% in group II, and 6.3% in group III (p = 0.19). The rate of bronchial complications was 0.96% in group I, 0% in group II, and 7.9% in group III (p = 0.006). Five-year survival was 46.1% in group I, 42.9% in group II, and 30.4% in group III (p = 0.16). Freedom from local recurrence of disease (5 years) was 83.8% in group I, 84.2% in group II, and 88.7% in group III (p = 0.56). Bronchovascular sleeve resections are as safe as bronchial sleeve resections for the treatment of central lung cancer. Both procedures have comparable early and long-term results, which are similar to those of pneumonectomy. It appears reasonable to apply bronchovascular sleeve resections more liberally.

Ultralow refractive index optical films with enhanced mechanical performance obtained by hybrid glancing angle deposition.

PubMed

Trottier-Lapointe, W; Zabeida, O; Schmitt, T; Martinu, L

2016-11-01

Ultralow refractive index materials (n less than 1.38 at 550 nm) are of particular interest in the context of antireflective coatings, allowing one to enhance their overall optical performance. However, application of such materials is typically limited by their mechanical properties. In this study, we explore the characteristics of a new category of hybrid (organic/inorganic) SiOCH thin films prepared by glancing angle deposition (GLAD) using electron beam evaporation of SiO₂ in the presence of an organosilicon precursor. The resulting layers exhibited n as low as 1.2, showed high elastic rebound, and generally better mechanical properties than their inorganic counterparts. In addition, hybrid GLAD films were found to be highly hydrophobic. The performance of the films is discussed in terms of their hybridicity (organic/inorganic) ratio determined by infrared spectroscopic ellipsometry as well as the presence of anisotropy assessed by the nanostructure-based spectroscopic ellipsometry model. Finally, we demonstrate successful implementation of the ultralow-index material in a complete antireflective stack.

Development of Ultra-Low Noise, High Performance III-V Quantum Well Infrared Photodetectors (QWIPs) for Focal Plane Array Staring Image Sensor Systems

DTIC Science & Technology

1994-02-06

Ultra-Low Noise , High Performance lll-V Quantum Well Infrared Photodetectors ( QWIPs ) for Focal Plane Array Staring Image Sensor Systems i Submitted to i... QWIP , the noise is increased by the square root of the gain ,(g and the detectivity D" is reduced by this same factor. As shown in Fig. 3.18, the optimum...PI .4totekotP044l .t.,me. O IM A. AGENCY use ONLY (Leave blank) 1. y.p0AT J *fY E AND OATES CO r S - 0 1 DWveop cTteOf Ultra-Low Noise , High

250 Robotic Pancreatic Resections: Safety and Feasibility

PubMed Central

Zureikat, Amer H.; Moser, A. James; Boone, Brian A.; Bartlett, David L.; Zenati, Mazen; Zeh, Herbert J.

2015-01-01

Background and Objectives Computer Assisted Robotic Surgery allows complex resections and anastomotic reconstructions to be performed with nearly identical standards to open surgery. We applied this technology to a variety of pancreatic resections to assess the safety, feasibility, versatility and reliability of this technology. Methods A retrospective review of a prospective database of robotic pancreatic resections at a single institution between August 2008 and November 2012 was performed. Peri-operative outcomes were analyzed. Results 250 consecutive robotic pancreatic resections were analyzed; pancreaticoduodenectomy (PD =132), distal pancreatectomy (DP=83), central pancreatectomy (CP=13), pancreatic enucleation (10), total pancreatectomy (TP=5), Appleby resection (4), and Frey procedure (3). Thirty day and 90 day mortality was 0.8 % and 2.0%. Rate of Clavien 3 and 4 complications was 14 and 6 %. The ISGPF grade C fistula rate was 4%. Mean operative time for the two most common procedures was 529 ± 103 mins for PD, and 257 ± 93 mins for DP. Continuous improvement in operative times was observed over the course of the experience. Conversion to open procedure was required in 16 patients (6%);(11 PD, 2 DP, 2 CP, 1 TP) for failure to progress (14) and bleeding (2). Conclusions This represents to our knowledge the largest series of robotic pancreatic resections. Safety and feasibility metrics including the low incidence of conversion support the robustness of this platform and suggest no unanticipated risks inherent to this new technology. By defining these early outcome metrics this report begins to establish a framework for comparative effectiveness studies of this platform. PMID:24002300

Dna2 initiates resection at clean DNA double-strand breaks

PubMed Central

Paudyal, Sharad C.; Li, Shan; Yan, Hong; Hunter, Tony

2017-01-01

Abstract Nucleolytic resection of DNA double-strand breaks (DSBs) is essential for both checkpoint activation and homology-mediated repair; however, the precise mechanism of resection, especially the initiation step, remains incompletely understood. Resection of blocked ends with protein or chemical adducts is believed to be initiated by the MRN complex in conjunction with CtIP through internal cleavage of the 5′ strand DNA. However, it is not clear whether resection of clean DSBs with free ends is also initiated by the same mechanism. Using the Xenopus nuclear extract system, here we show that the Dna2 nuclease directly initiates the resection of clean DSBs by cleaving the 5′ strand DNA ∼10–20 nucleotides away from the ends. In the absence of Dna2, MRN together with CtIP mediate an alternative resection initiation pathway where the nuclease activity of MRN apparently directly cleaves the 5′ strand DNA at more distal sites. MRN also facilitates resection initiation by promoting the recruitment of Dna2 and CtIP to the DNA substrate. The ssDNA-binding protein RPA promotes both Dna2- and CtIP–MRN-dependent resection initiation, but a RPA mutant can distinguish between these pathways. Our results strongly suggest that resection of blocked and clean DSBs is initiated via distinct mechanisms. PMID:28981724

Association of narrow angles with anterior chamber area and volume measured with anterior-segment optical coherence tomography.

PubMed

Wu, Ren-Yi; Nongpiur, Monisha E; He, Ming-Guang; Sakata, Lisandro M; Friedman, David S; Chan, Yiong-Huak; Lavanya, Raghavan; Wong, Tien-Yin; Aung, Tin

2011-05-01

To describe the measurement of anterior chamber area and anterior chamber volume by anterior-segment optical coherence tomography and to investigate the association of these parameters with the presence of narrow angles. This was a cross-sectional study of subjects aged at least 50 years without ophthalmic symptoms recruited from a community clinic. All participants underwent standardized ocular examination and anterior-segment optical coherence tomography. Customized software was used to measure anterior chamber area (cross-sectional area bounded by the corneal endothelium, anterior surface of iris, and lens within the pupil) and anterior chamber volume (calculated by rotating the anterior chamber area 360° around a vertical axis through the midpoint of the anterior chamber area). An eye was considered to have narrow angles if the posterior pigmented trabecular meshwork was not visible for at least 180° on gonioscopy with the eye in the primary position. A total of 1922 subjects were included in the final analyses, 317 (16.5%) of whom had narrow angles. Mean anterior chamber area (15.6 vs 21.1 mm(2); P < .001) and anterior chamber volume (97.6 vs 142.1 mm(3); P < .001) were smaller in eyes with narrow angles compared with those in eyes without narrow angles. After adjusting for age, sex, anterior chamber depth, axial length, and pupil size, smaller anterior chamber area (odds ratio, 53.2; 95% confidence interval, 27.1-104.5) and anterior chamber volume (odds ratio, 40.2; 95% confidence interval, 21.5-75.2) were significantly associated with the presence of narrow angles. Smaller anterior chamber area and anterior chamber volume were independently associated with narrow angles in Singaporeans, even after controlling for other known ocular risk factors.

Ductal drainage or resection for chronic pancreatitis.

PubMed

Taylor, R H; Bagley, F H; Braasch, J W; Warren, K W

1981-01-01

We report a 10 year review comparing the results of pain relief after three procedures for chronic pancreatitis: Whipple pancreatoduodenectomy, modified Puestow side-to-side longitudinal pancreaticojejunostomy and distal pancreatic resection. Results of follow-up review at 6 months, 2 years and 5 years were tabulated. Five year follow-up data were available on more than 80 percent of patients. The proportion of good results for pain relief decreased with the passage of time regardless of the procedure performed. Although equally good results are obtained after either pancreatoduodenectomy or pancreaticojejunosotomy, we conclude that in the presence of a dilated duct, the procedure of choice is pancreaticojejunostomy. If the duct is not dilated, we then favor pancreatoduodenectomy, after which the pain relief is significantly better (p = 0.05) than after distal resection. Our data show that, for all factors evaluated, the poorest pain relief was obtained after distal resection. Therefore that procedure has limited value when used specifically for relief of pain in chronic pancreatitis, except in the uncommon circumstance when the disease is confined to the distal part of the gland. Our study also shows that patients who have more radical distal resection have no better pain relief than those who have 50 percent distal resection.

Resection for secondary malignancy of the pancreas.

PubMed

Hung, Jui-Hsia; Wang, Shin-E; Shyr, Yi-Ming; Su, Cheng-Hsi; Chen, Tien-Hua; Wu, Chew-Wun

2012-01-01

This study tried to clarify the role of pancreatic resection in the treatment of secondary malignancy with metastasis or local invasion to the pancreas in terms of surgical risk and survival benefit. Data of secondary malignancy of the pancreas from our 19 patients and cases reported in the English literature were pooled together for analysis. There were 329 cases of resected secondary malignancy of the pancreas, including 241 cases of metastasis and 88 cases of local invasion. The most common primary tumor metastatic to the pancreas and amenable to resection was renal cell carcinoma (RCC) (73.9%). More than half (52.3%) of the primary cancers with local invasion to the pancreas were colon cancer, and nearly half (40.9%) were stomach cancer. The median metastatic interval was 84 months (7 years) for overall primary tumors and 108 months (9 years) for RCC. The 5-year survival for secondary malignancy of the pancreas after resection was 61.1% for metastasis and 58.9% for local invasion, with 72.8% for RCC metastasis, 69.0% for colon cancer, and 43.8% for stomach cancer with local invasion to the pancreas. Pancreatic resection should not be precluded for secondary malignancy of the pancreas because long-term survival could be achieved with acceptable surgical risk in selected patients.

A model for morbidity after lung resection in octogenarians.

PubMed

Berry, Mark F; Onaitis, Mark W; Tong, Betty C; Harpole, David H; D'Amico, Thomas A

2011-06-01

Age is an important risk factor for morbidity after lung resection. This study was performed to identify specific risk factors for complications after lung resection in octogenarians. A prospective database containing patients aged 80 years or older, who underwent lung resection at a single institution between January 2000 and June 2009, was reviewed. Preoperative, histopathologic, perioperative, and outcome variables were assessed. Morbidity was measured as a patient having any perioperative event as defined by the Society of Thoracic Surgeons General Thoracic Surgery Database. A multivariable risk model for morbidity was developed using a panel of established preoperative and operative variables. Survival was calculated using the Kaplan-Meier method. During the study period, 193 patients aged 80 years or older (median age 82 years) underwent lung resection: wedge resection in 77, segmentectomy in 13, lobectomy in 96, bilobectomy in four, and pneumonectomy in three. Resection was accomplished via thoracoscopy in 149 patients (77%). Operative mortality was 3.6% (seven patients) and morbidity was 46% (89 patients). A total of 181 (94%) patients were discharged directly home. Postoperative events included atrial arrhythmia in 38 patients (20%), prolonged air leak in 24 patients (12%), postoperative transfusion in 22 patients (11%), delirium in 16 patients (8%), need for bronchoscopy in 14 patients (7%), and pneumonia in 10 patients (5%). Significant predictors of morbidity by multivariable analysis included resection greater than wedge (odds ratio 2.98, p=0.006), thoracotomy as operative approach (odds ratio 2.6, p=0.03), and % predicted forced expiratory volume in 1s (odds ratio 1.28 for each 10% decrement, p=0.01). Octogenarians can undergo lung resection with low mortality. Extent of resection, use of a thoracotomy, and impaired lung function increase the risk of complications. Careful evaluation is necessary to select the most appropriate approach in

Progress of liver resection for hepatocellular carcinoma in Taiwan.

PubMed

Wu, Cheng-Chung

2017-05-01

Taiwan is a well-known endemic area of hepatitis B. Hepatocellular carcinoma (HCC) has consistently been the first or second highest cause of cancer death over the past 20 years. This review article describes the progress of liver resection for HCC in Taiwan in the past half century. The mortality rate for HCC resection was 15-30% in Taiwan in the 1970s. The rate decreased to 8-12% in the early 1990s, and it declined to <1-3% recently. The development of new operative instruments, and surgical techniques, increased knowledge of liver anatomy and pathophysiology after hepatectomy, and more precise patient selection have contributed to this improvement. The use of intermittent hepatic inflow blood occlusion, a restrictive blood transfusion policy and intraoperative ultrasonography, have also led to substantial improvements in resectability and safety for HCC resection in Taiwan. Advances in non-operative modalities for HCC treatment have also helped to improve long-term outcomes of HCC resection. Technical innovations have allowed the application of complex procedures such as mesohepatectomy, unroofing hepatectomy, major portal vein thrombectomy, hepatic vein reconstruction in resection of the cranial part with preservation of the caudal part of the liver, and inferior vena cava and right atrium tumor thrombectomy under cardiopulmonary bypass. In selected patients, including patients with end-stage renal failure, renal graft recipients, patients with portal hypertension, hypersplenic thrombocytopenia and/or associated gastroesophageal varices, octogenarian, ruptured HCC, recurrent HCC and metastatic HCC can also be resected with satisfactory survival benefits. We conclude that the results of liver resection for HCC in Taiwan are improving. The indications for HCC resection continue extending with lower the surgical risks and increasing the long-term survival rate. © The Author 2017. Published by Oxford University Press. All rights reserved. For Permissions, please e

Comprehension of Concrete and Abstract Words in Patients with Selective Anterior Temporal Lobe Resection and in Patients with Selective Amygdalo-Hippocampectomy

ERIC Educational Resources Information Center

Loiselle, Magalie; Rouleau, Isabelle; Nguyen, Dang Khoa; Dubeau, Francois; Macoir, Joel; Whatmough, Christine; Lepore, Franco; Joubert, Sven

2012-01-01

The role of the anterior temporal lobe (ATL) in semantic memory is now firmly established. There is still controversy, however, regarding the specific role of this region in processing various types of concepts. There have been reports of patients suffering from semantic dementia (SD), a neurodegenerative condition in which the ATL is damaged…

Convex Hemiepiphysiodesis: Posterior/anterior in-situ Versus Posterior-only With Pedicle Screw Instrumentation: An Experimental Simulation in Immature Pigs.

PubMed

Bekmez, Senol; Demirkiran, Halil G; Yilmaz, Guney; Akel, Ibrahim; Atilla, Pergin; Muftuoglu, Sevda Fatma; Yazici, Muharrem; Alanay, Ahmet

2016-12-01

Experimental study. Convex growth arrest (CGA) has been commonly used in the treatment of long-sweeping congenital deformities of the immature spine. As there are major drawbacks about the anterior procedure in the conventional CGA method, a new modification has been documented that using only posterior spinal approach with pedicle screw instrumentation. The aim of the study was to compare posterior-only CGA using pedicle screws with combined anterior/posterior in-situ CGA for the findings in histologic, radiologic, and manual palpation examinations in an immature pig model. Twelve 10-weeks old pigs were grouped into 2. In group 1, posterior-only, pedicle screw instrumented CGA was performed on the left side of L1-L4 vertebrae. In group 2, conventional combined posterior and anterior CGA was performed to the left side of L1-L4 vertebrae without instrumentation. All animals were killed twelve weeks after surgery. T11-L5 segments were en-bloc resected and radiologic, histologic, and manual palpation examinations were done. Marked scoliotic (12.2±2.5 and 9.2±1.3 in group 1 and 2, respectively) and kyphotic (11.2±1.0 degrees for the group 1 and 12±5.2 degrees for the group 2, respectively) deformities were noted in both groups, which were caused by hemiepiphysiodesis effect. Anterior and posterior parts of group 2 and posterior part of group 1 demonstrated fusion in histologic and radiologic analyzes. In anterior part of the group 1, marked narrowing on the disk spaces and thinning of growth plates were noted in radiologicg examination, chondrocyte degeneration, and newly-formed bone trabeculae in disk-space were noted in histological examination. In manual palpation, no motion was detected in group 1 and motion was detected in only one segment of one animal in group 2. Anterior growth of the vertebrae can be controlled by application of posterior transpedicular screws and rod. Such an effect can eliminate the need for anterior surgical intervention in convex

A photon recycling approach to the denoising of ultra-low dose X-ray sequences.

PubMed

Hariharan, Sai Gokul; Strobel, Norbert; Kaethner, Christian; Kowarschik, Markus; Demirci, Stefanie; Albarqouni, Shadi; Fahrig, Rebecca; Navab, Nassir

2018-06-01

Clinical procedures that make use of fluoroscopy may expose patients as well as the clinical staff (throughout their career) to non-negligible doses of radiation. The potential consequences of such exposures fall under two categories, namely stochastic (mostly cancer) and deterministic risks (skin injury). According to the "as low as reasonably achievable" principle, the radiation dose can be lowered only if the necessary image quality can be maintained. Our work improves upon the existing patch-based denoising algorithms by utilizing a more sophisticated noise model to exploit non-local self-similarity better and this in turn improves the performance of low-rank approximation. The novelty of the proposed approach lies in its properly designed and parameterized noise model and the elimination of initial estimates. This reduces the computational cost significantly. The algorithm has been evaluated on 500 clinical images (7 patients, 20 sequences, 3 clinical sites), taken at ultra-low dose levels, i.e. 50% of the standard low dose level, during electrophysiology procedures. An average improvement in the contrast-to-noise ratio (CNR) by a factor of around 3.5 has been found. This is associated with an image quality achieved at around 12 (square of 3.5) times the ultra-low dose level. Qualitative evaluation by X-ray image quality experts suggests that the method produces denoised images that comply with the required image quality criteria. The results are consistent with the number of patches used, and they demonstrate that it is possible to use motion estimation techniques and "recycle" photons from previous frames to improve the image quality of the current frame. Our results are comparable in terms of CNR to Video Block Matching 3D-a state-of-the-art denoising method. But qualitative analysis by experts confirms that the denoised ultra-low dose X-ray images obtained using our method are more realistic with respect to appearance.

Large bowel resection

MedlinePlus

... blockage in the intestine due to scar tissue Colon cancer Diverticular disease (disease of the large bowel) Other reasons for bowel resection are: Familial polyposis (polyps are growths on the lining of the colon or rectum) Injuries that damage the large bowel ...

Upfront chemotherapy and subsequent resection for molecularly defined gliomas.

PubMed

Sasaki, Hikaru; Hirose, Yuichi; Yazaki, Takahito; Kitamura, Yohei; Katayama, Makoto; Kimura, Tokuhiro; Fujiwara, Hirokazu; Toda, Masahiro; Ohira, Takayuki; Yoshida, Kazunari

2015-08-01

Functional preservation is critical in glioma surgery, and the extent of resection influences survival outcome. Neoadjuvant chemotherapy is a promising option because of its potential to facilitate tumor shrinkage and maximum tumor resection. The object of this study was to assess the utility of the neoadjuvant strategy in a prospective series of gliomas with favorable molecular status. Twenty-six consecutive cases of diffuse gliomas of WHO grade II or III with either 1p19q codeletion or MGMT methylation were treated with upfront chemotherapy following maximal safe removal. In cases of incomplete initial surgery, second-look resection was intended after tumor volume decrease by chemotherapy. Among 22 evaluable cases, chemotherapy led to a median change in the sum of the product of perpendicular diameters of -35 %, and 14 out of the 22 cases (64 %) showed objective response. Second-look resection after tumor volume decrease was performed in 12 out of 19 cases of incomplete initial surgery (GTR/STR 9, removal of residual methionine PET uptake 3). The median progression-free survival among the 22 patients with grade II tumors was 57 months, with some cases showing durable progression-free survival after second-look resection. MIB-1 indices of the second-look resected tumors were lower than those of the initial tumors, and the methylation status of the MGMT gene was unchanged. Neoadjuvant chemotherapy based on molecular guidance often produces significant volume decrease of incompletely resected gliomas. Radical second-look resection is an optional advantage of upfront chemotherapy for chemosensitive gliomas compared with initial radiotherapy.

[Current Status of Endoscopic Resection of Early Gastric Cancer in Korea].

PubMed

Jung, Hwoon Yong

2017-09-25

Endoscopic resection (Endoscopic mucosal resection [EMR] and endoscopic submucosal dissection [ESD]) is already established as a first-line treatment modality for selected early gastric cancer (EGC). In Korea, the number of endoscopic resection of EGC was explosively increased because of a National Cancer Screening Program and development of devices and techniques. There were many reports on the short-term and long-term outcomes after endoscopic resection in patients with EGC. Long-term outcome in terms of recurrence and death is excellent in both absolute and selected expanded criteria. Furthermore, endoscopic resection might be positioned as primary treatment modality replacing surgical gastrectomy. To obtain these results, selection of patients, perfect en bloc procedure, thorough pathological examination of resected specimen, accurate interpretation of whole process of endoscopic resection, and rational strategy for follow-up is necessary.

Nanogap-Engineerable Electromechanical System for Ultralow Power Memory.

PubMed

Zhang, Jian; Deng, Ya; Hu, Xiao; Nshimiyimana, Jean Pierre; Liu, Siyu; Chi, Xiannian; Wu, Pei; Dong, Fengliang; Chen, Peipei; Chu, Weiguo; Zhou, Haiqing; Sun, Lianfeng

2018-02-01

Nanogap engineering of low-dimensional nanomaterials has received considerable interest in a variety of fields, ranging from molecular electronics to memories. Creating nanogaps at a certain position is of vital importance for the repeatable fabrication of the devices. Here, a rational design of nonvolatile memories based on sub-5 nm nanogaped single-walled carbon nanotubes (SWNTs) via the electromechanical motion is reported. The nanogaps are readily realized by electroburning in a partially suspended SWNT device with nanoscale region. The SWNT memory devices are applicable for both metallic and semiconducting SWNTs, resolving the challenge of separation of semiconducting SWNTs from metallic ones. Meanwhile, the memory devices exhibit excellent performance: ultralow writing energy (4.1 × 10 -19 J bit -1 ), ON/OFF ratio of 10 5 , stable switching ON operations, and over 30 h retention time in ambient conditions.

Nanogap‐Engineerable Electromechanical System for Ultralow Power Memory

PubMed Central

Zhang, Jian; Deng, Ya; Hu, Xiao; Nshimiyimana, Jean Pierre; Liu, Siyu; Chi, Xiannian; Wu, Pei; Dong, Fengliang; Chen, Peipei

2017-01-01

Abstract Nanogap engineering of low‐dimensional nanomaterials has received considerable interest in a variety of fields, ranging from molecular electronics to memories. Creating nanogaps at a certain position is of vital importance for the repeatable fabrication of the devices. Here, a rational design of nonvolatile memories based on sub‐5 nm nanogaped single‐walled carbon nanotubes (SWNTs) via the electromechanical motion is reported. The nanogaps are readily realized by electroburning in a partially suspended SWNT device with nanoscale region. The SWNT memory devices are applicable for both metallic and semiconducting SWNTs, resolving the challenge of separation of semiconducting SWNTs from metallic ones. Meanwhile, the memory devices exhibit excellent performance: ultralow writing energy (4.1 × 10−19 J bit−1), ON/OFF ratio of 105, stable switching ON operations, and over 30 h retention time in ambient conditions. PMID:29619307

Ultra-low density microcellular polymer foam and method

DOEpatents

Simandl, Ronald F.; Brown, John D.

1996-01-01

An ultra-low density, microcellular open-celled polymer foam and a method for making such foam. A polymer is dissolved in a heated solution consisting essentially of at least one solvent for the dissolution of the polymer in the heated solution and the phase inversion of the dissolved polymer to a liquid gel upon sufficient cooling of the heated solution. The heated solution is contained in a containment means provided with a nucleating promoting means having a relatively rough surface formed of fixed nucleating sites. The heated solution is cooled for a period of time sufficient to form a liquid gel of the polymer by phase inversion. From the gel, a porous foam having a density of less than about 12.0 mg/cm.sup.3 and open porosity provided by well interconnected strut morphology is formed.

Ultra-low density microcellular polymer foam and method

DOEpatents

Simandl, R.F.; Brown, J.D.

1996-03-19

An ultra-low density, microcellular open-celled polymer foam and a method for making such foam are disclosed. A polymer is dissolved in a heated solution consisting essentially of at least one solvent for the dissolution of the polymer in the heated solution and the phase inversion of the dissolved polymer to a liquid gel upon sufficient cooling of the heated solution. The heated solution is contained in a containment means provided with a nucleating promoting means having a relatively rough surface formed of fixed nucleating sites. The heated solution is cooled for a period of time sufficient to form a liquid gel of the polymer by phase inversion. From the gel, a porous foam having a density of less than about 12.0 mg/cm{sup 3} and open porosity provided by well interconnected strut morphology is formed.

Robotic versus laparoscopic resection of liver tumours

PubMed Central

Berber, Eren; Akyildiz, Hizir Yakup; Aucejo, Federico; Gunasekaran, Ganesh; Chalikonda, Sricharan; Fung, John

2010-01-01

Background There are scant data in the literature regarding the role of robotic liver surgery. The aim of the present study was to develop techniques for robotic liver tumour resection and to draw a comparison with laparoscopic resection. Methods Over a 1-year period, nine patients underwent robotic resection of peripherally located malignant lesions measuring <5 cm. These patients were compared prospectively with 23 patients who underwent laparoscopic resection of similar tumours at the same institution. Statistical analyses were performed using Student's t-test, χ2-test and Kaplan–Meier survival. All data are expressed as mean ± SEM. Results The groups were similar with regards to age, gender and tumour type (P = NS). Tumour size was similar in both groups (robotic −3.2 ± 1.3 cm vs. laparoscopic −2.9 ± 1.3 cm, P = 0.6). Skin-to-skin operative time was 259 ± 28 min in the robotic vs. 234 ± 17 min in the laparoscopic group (P = 0.4). There was no difference between the two groups regarding estimated blood loss (EBL) and resection margin status. Conversion to an open operation was only necessary in one patient in the robotic group. Complications were observed in one patient in the robotic and four patients in the laparoscopic groups. The patients were followed up for a mean of 14 months and disease-free survival (DFS) was equivalent in both groups (P = 0.6). Conclusion The results of this initial study suggest that, for selected liver lesions, a robotic approach provides similar peri-operative outcomes compared with laparoscopic liver resection (LLR). PMID:20887327

Robotic Liver Resection: A Case-Matched Comparison.

PubMed

Kingham, T Peter; Leung, Universe; Kuk, Deborah; Gönen, Mithat; D'Angelica, Michael I; Allen, Peter J; DeMatteo, Ronald P; Laudone, Vincent P; Jarnagin, William R; Fong, Yuman

2016-06-01

In recent years, increasingly sophisticated tools have allowed for more complex robotic surgery. Robotic hepatectomy, however, is still in its infancy. Our goals were to examine the adoption of robotic hepatectomy and to compare outcomes between open and robotic liver resections. The robotic hepatectomy experience of 64 patients was compared to a modern case-matched series of 64 open hepatectomy patients at the same center. Matching was according to benign/malignant diagnosis and number of segments resected. Patient data were obtained retrospectively. The main outcomes and measures were operative time, estimated blood loss, conversion rate (robotic to open), Pringle maneuver use, single non-anatomic wedge resection rate, resection margin size, complication rates (infectious, hepatic, pulmonary, cardiac), hospital stay length, ICU stay length, readmission rate, and 90-day mortality rate. Sixty-four robotic hepatectomies were performed in 2010-2014. Forty-one percent were segmental and 34 % were wedge resections. There was a 6 % conversion rate, a 3 % 90-day mortality rate, and an 11 % morbidity rate. Compared to 64 matched patients who underwent open hepatectomy (2004-2012), there was a shorter median OR time (p = 0.02), lower median estimated blood loss (p < 0.001), and shorter median hospital stay (p < 0.001). Eleven of the robotic cases were isolated resections of tumors in segments 2, 7, and 8. Robotic hepatectomy is safe and effective. Increasing experience in more centers will allow definition of which hepatectomies can be performed robotically, and will enable optimization of outcomes and prospective examination of the economic cost of each approach.

Ultralow-field and spin-locking relaxation dispersion in postmortem pig brain.

PubMed

Dong, Hui; Hwang, Seong-Min; Wendland, Michael; You, Lixing; Clarke, John; Inglis, Ben

2017-12-01

To investigate tissue-specific differences, a quantitative comparison was made between relaxation dispersion in postmortem pig brain measured at ultralow fields (ULF) and spin locking at 7 tesla (T). The goal was to determine whether ULF-MRI has potential advantages for in vivo human brain imaging. Separate specimens of gray matter and white matter were investigated using an ULF-MRI system with superconducting quantum interference device (SQUID) signal detection to measure T1ULF at fields from 58.7 to 235.0 μT and using a commercial MRI scanner to measure T1ρ7T at spin-locking fields from 5.0 to 235.0 μT. At matched field strengths, T1ρ7T is 50 to 100% longer than T1ULF. Furthermore, dispersion in T1ULF is close to linear between 58.7 and 235 µT, whereas dispersion in T1ρ7T is highly nonlinear over the same range. A subtle elbow in the T1ULF dispersion at approximately 140 µT is tentatively attributed to the local dipolar field of macromolecules. It is suggested that different relaxation mechanisms dominate each method and that ULF-MRI has a fundamentally different sensitivity to the macromolecular structure of neural tissue. Ultralow-field MRI may offer distinct, quantitative advantages for human brain imaging, while simultaneously avoiding the severe heating limitation imposed on high-field spin locking. Magn Reson Med 78:2342-2351, 2017. © 2016 International Society for Magnetic Resonance in Medicine. © 2017 International Society for Magnetic Resonance in Medicine.

Major vascular resections in retroperitoneal sarcoma.

PubMed

Tzanis, Dimitri; Bouhadiba, Toufik; Gaignard, Elodie; Bonvalot, Sylvie

2018-01-01

Retroperitoneal sarcomas (RPS) frequently involve major vessels, which either originate from them or secondarily encase or invade them. In this field, major vascular resections result in increased morbidity. However, survival does not seem to be affected by the need for vascular resection or by this higher morbidity. This paper aims to provide descriptions of the surgical strategy and outcomes for retroperitoneal sarcomas involving major vessels. © 2017 Wiley Periodicals, Inc.

Ultra-low power, Zeno effect based optical modulation in a degenerate V-system with a tapered nano fiber in atomic vapor.

PubMed

Salit, K; Salit, M; Krishnamurthy, Subramanian; Wang, Y; Kumar, P; Shahriar, M S

2011-11-07

We demonstrate an ultra-low light level optical modulator using a tapered nano fiber embedded in a hot rubidium vapor. The control and signal beams are co-propagating but orthogonally polarized, leading to a degenerate V-system involving coherent superpositions of Zeeman sublevels. The modulation is due primarily to the quantum Zeno effect for the signal beam induced by the control beam. For a control power of 40 nW and a signal power of 100 pW, we observe near 100% modulation. The ultra-low power level needed for the modulation is due to a combination of the Zeno effect and the extreme field localization in the evanescent field around the taper.

Outcomes after resection of occupational cholangiocarcinoma.

PubMed

Kubo, Shoji; Takemura, Shigekazu; Tanaka, Shogo; Shinkawa, Hiroji; Kinoshita, Masahiko; Hamano, Genya; Ito, Tokuji; Koda, Masaki; Aota, Takanori; Yamamoto, Takatsugu; Terajima, Hiroaki; Tachiyama, Gorou; Yamada, Terumasa; Nakamori, Shoji; Arimoto, Akira; Fujikawa, Masahiro; Tomimaru, Yoshito; Sugawara, Yasuhiko; Nakagawa, Kei; Unno, Michiaki; Mizuguchi, Toru; Takenaka, Kenji; Kimura, Koichi; Shirabe, Ken; Saiura, Akio; Uesaka, Katsuhiko; Taniguchi, Hiroki; Fukuda, Akira; Chong, Ja-Mun; Kuwae, Yuko; Ohsawa, Masahiko; Sato, Yasunori; Nakanuma, Yasuni

2016-09-01

Cholangiocarcinoma caused by exposure to 1,2-dichloropropane and/or dichloromethane is recognized as occupational cholangiocarcinoma. The aim of this study was to investigate the outcomes after resection of occupational cholangiocarcinoma to establish a treatment strategy for this disease. Clinicopathological findings and outcomes after surgical intervention in 20 patients with occupational cholangiocarcinoma were investigated. Of 20 the patients, curative resection was performed in 16 patients. Three patients underwent radiation at the stump of the bile ducts. Adjuvant chemotherapy was performed in 12 patients. Biliary intraepithelial neoplasia, intraductal papillary neoplasm of the bile duct, and/or chronic bile duct injury was detected in most subjects. Intraabdominal infection developed after surgery in nine patients. Cholangiocarcinoma recurred in 12 of the 20 patients. The recurrent tumors in five patients developed at a different part of the bile duct from the primary tumor and a second resection was performed in four of these five patients. The incidence of postoperative complications including intraabdominal infection was high in patients with occupational cholangiocarcinoma. Multicentric recurrence occurred not infrequently after surgery because the bile ducts had a high potential for the development of carcinoma. The aggressive treatment including second resection for the multicentric recurrence appeared to be effective. © 2016 Japanese Society of Hepato-Biliary-Pancreatic Surgery.

Role of hepatic resection for patients with carcinoid heart disease.

PubMed

Bernheim, Alain M; Connolly, Heidi M; Rubin, Joseph; Møller, Jacob E; Scott, Christopher G; Nagorney, David M; Pellikka, Patricia A

2008-02-01

To evaluate the effects of resection of hepatic carcinoid metastases on progression and prognosis of carcinoid heart disease. From our database of 265 consecutive patients diagnosed as having carcinoid heart disease from January 1, 1980, through December 31, 2005, we calculated survival from first diagnosis of cardiac involvement. Hepatic resection during follow-up was entered as a time-dependent covariable in a multivariable analysis. In patients with serial echocardiograms more than 1 year apart without intervening cardiac surgery, a previously validated cardiac severity score was calculated. A score increase that exceeded 25% was considered relevant progression. Hepatic resection was performed in 31 patients (12%) during follow-up. Five-year survival was significantly higher in these patients (86.5%; 95% confidence interval [CI], 73.5%-100.0%) than in patients without hepatic resection (29.0%; 95% CI, 23.3%-36.1%; univariable hazard ratio for hepatic resection, 0.25; 95% CI 0.12-0.53; P<.001). Hepatic resection remained strongly associated with improved prognosis in multivariable analysis (hazard ratio, 0.31; 95% CI, 0.14-0.66; P=.003). Among 77 patients (29%) with serial echocardiograms, 10 (13%) underwent hepatic resection during follow-up; resection was independently associated with decreased risk of cardiac progression (odds ratio, 0.29; 95% CI, 0.06-0.75; P=.03). Despite the limitations of this retrospective nonrandomized study, our data suggest that patients with carcinoid heart disease who undergo hepatic resection have decreased cardiac progression and improved prognosis. Eligible patients should be considered for hepatic surgery.

Acquisition, preprocessing, and reconstruction of ultralow dose volumetric CT scout for organ-based CT scan planning

DOE Office of Scientific and Technical Information (OSTI.GOV)

Yin, Zhye, E-mail: yin@ge.com; De Man, Bruno; Yao, Yangyang

Purpose: Traditionally, 2D radiographic preparatory scan images (scout scans) are used to plan diagnostic CT scans. However, a 3D CT volume with a full 3D organ segmentation map could provide superior information for customized scan planning and other purposes. A practical challenge is to design the volumetric scout acquisition and processing steps to provide good image quality (at least good enough to enable 3D organ segmentation) while delivering a radiation dose similar to that of the conventional 2D scout. Methods: The authors explored various acquisition methods, scan parameters, postprocessing methods, and reconstruction methods through simulation and cadaver data studies tomore » achieve an ultralow dose 3D scout while simultaneously reducing the noise and maintaining the edge strength around the target organ. Results: In a simulation study, the 3D scout with the proposed acquisition, preprocessing, and reconstruction strategy provided a similar level of organ segmentation capability as a traditional 240 mAs diagnostic scan, based on noise and normalized edge strength metrics. At the same time, the proposed approach delivers only 1.25% of the dose of a traditional scan. In a cadaver study, the authors’ pictorial-structures based organ localization algorithm successfully located the major abdominal-thoracic organs from the ultralow dose 3D scout obtained with the proposed strategy. Conclusions: The authors demonstrated that images with a similar degree of segmentation capability (interpretability) as conventional dose CT scans can be achieved with an ultralow dose 3D scout acquisition and suitable postprocessing. Furthermore, the authors applied these techniques to real cadaver CT scans with a CTDI dose level of less than 0.1 mGy and successfully generated a 3D organ localization map.« less

One-stage posterior-only lumbosacral hemivertebra resection with short segmental fusion: a more than 2-year follow-up.

PubMed

Zhuang, Qianyu; Zhang, Jianguo; Li, Shugang; Wang, Shengru; Guo, Jianwei; Qiu, Guixing

2016-05-01

Lumbosacral hemivertebra poses a unique problem because it can cause gross imbalance and progressive compensatory thoracolumbar deformity. Previous studies have reported lumbosacral hemivertebra resection through a combined anterior and posterior approach, but there have been no reports on the results and complications of hemivertebra resection via a posterior-only procedure and short fusion with large series of patients. This retrospective study of a prospective collected database comprises a consecutive series of 14 congenital scoliosis due to lumbosacral hemivertebra treated by 1-stage posterior hemivertebra resection with short segmental fusion, with at least a 2-year follow-up period (24-144 months). Surgical reports and patient charts were reviewed. Radiographic evaluation included measured changes in segmental scoliosis and lordosis, compensatory scoliosis, thoracic kyphosis, lumbar lordosis, and trunk shift. Quality of life data from Scoliosis Research Society (SRS)-22 questionnaires were also collected. Our results showed that the mean follow-up period was 38.4 months. The mean fusion level was 3.2 segments. Mean operation time was 207.8 min with the average blood loss of 235.7 ml. The mean segmental scoliosis was 30° preoperatively, 5° postoperatively (83 % correction rate), and 4° (87 %) at the latest follow-up. The compensatory coronal curve of 30° was spontaneously corrected to 13° at most recent follow-up. Trunk shift was significantly improved on both coronal (63 %) and sagittal plane (58 %) after the surgery, and kept stable during the follow-up. The total SRS-22 score, the self-image domain score and the satisfaction domain score demonstrated significant improvement compared with preoperative status. Only one intra-operative complication was observed, a pedicle fracture. In summary, our results showed that one-stage HV resection and short segment fusion by a posterior approach can offer excellent scoliosis correction and trunk shift

Scheimpflug imaging in anterior megalophthalmos.

PubMed

Nemeth, Gabor; Hassan, Ziad; Berta, Andras; Modis, Laszlo

2013-01-01

We report an anterior megalophthalmos case with decreased corneal thickness and show the findings using Scheimpflug imaging. A 25-year-old male was diagnosed with anterior megalophthalmos. In both eyes, enlarged corneal length was measured. Beside a comparatively good visual acuity, a thin but clear cornea, a fairly deep anterior chamber, and central lens opacity were found. Scheimpflug images were taken using Pentacam HR. Scheimpflug-based imaging can provide us new data at the examination of this syndrome affecting the whole anterior segment.

From scratch: developing a hepatic resection service for metastatic colorectal cancer.

PubMed

Wylie, Neil; Hider, Phillip; Armstrong, Delwyn; Rajkomar, Kheman; Srinivasa, Sanket; Rodgers, Michael; Brown, Anna; Koea, Jonathan

2018-05-01

Waitemata District Health Board has New Zealand's largest catchment and busiest colorectal unit. The upper gastrointestinal unit was established in 2005, in part to provide a hepatic resection service for patients with colorectal carcinoma metastatic to the liver. The aim of this investigation was to report on quality indicators for the hepatic resection of colorectal carcinoma in the development of a regional resection service. Prospectively collected data on patients undergoing hepatic resection for colorectal carcinoma between 2005 and 2014 was reviewed and correlated with costing data and national hepatic resection rates. A total of 123 patients underwent 138 hepatic resections for metastatic colorectal cancer with a median hospital stay of 8 days (range 4-37 days), a zero 30-day mortality and a median cost of NZ$21 374 for minor hepatectomy and NZ$43 133 for major hepatectomy. Actuarial 5-year disease-free survival was 44%, with 28 patients alive and disease free at 5 years post-resection. Median overall survival was not reached. Review of national hepatic resection rates indicate that Waitemata District Health Board performs one sixth of all hepatic resections in New Zealand and that this treatment modality may be underutilized in the management of patients with metastatic colorectal cancer. A regional hepatic resection centre for colorectal metastases can be established in areas of population need and can provide a high-quality, cost-effective service. © 2016 Royal Australasian College of Surgeons.

[Laparoscopic resection of the sigmoid colon for the diverticular disease].

PubMed

Vrbenský, L; Simša, J

2013-07-01

Laparoscopic resection of the sigmoid colon for diverticular disease is nowadays a fully accepted alternative to traditional open procedures. The aim of this work is to summarize the indications, advantages and risks of laparoscopic sigmoid resection for diverticular disease. Review of the literature and recent findings concerning the significance of laparoscopic resection for diverticulosis of the sigmoid colon. The article presents the indications, risks, techniques and perioperative care in patients after laparoscopic resection of the sigmoid colon for diverticular disease.

Extra-articular shoulder resections: outcomes of 54 patients.

PubMed

Angelini, Andrea; Mavrogenis, Andreas F; Trovarelli, Giulia; Pala, Elisa; Arbelaez, Pablo; Casanova, Josè; Berizzi, Antonio; Ruggieri, Pietro

2017-11-01

The survival of patients with tumors around the shoulder treated with extra-articular resection, the rates of reconstructions-related complications, and the function of the shoulder cannot be estimated because of limited available data from mainly small published related series and case reports. We studied 54 patients with tumors around the shoulder treated with extra-articular shoulder resections and proximal humeral megaprosthetic reconstructions from 1985 to 2012. Mean tumor volume was 549 cm 3 , and the mean length of the proximal humeral resection was 110 mm. Mean follow-up was 7.8 years (range, 3-21 years). We evaluated the outcomes (survival, metastases, recurrences, and function) and the survival and complications of the reconstruction. Survival of patients with malignant tumors was 47%, 38%, and 35%, at 5, 10, and 20 years, respectively. Rates for metastasis and local recurrence were 60% and 18.5%, respectively. Survival was significantly higher for patients without metastases at diagnosis, tumor volume <549 cm 3 , and type IV resections. Survival of reconstructions was 56% at 10 years and 48% 20 years. Overall, 19 patients (35.2%) experienced 30 complications (55.5%), the most common being soft tissue failures that required subsequent surgery without, however, implant removal. The mean Musculoskeletal Tumour Society score was 25 points, without any significant difference between the types of extra-articular resections. Tumor stage and volume as well as type of resection are important predictors of survival of patients with malignant tumors around the shoulder. Survival of the reconstructions is satisfactory; nevertheless, the complication rate is high. The Musculoskeletal Tumour Society score is similar with respect to the type of resection. Copyright © 2017 Journal of Shoulder and Elbow Surgery Board of Trustees. Published by Elsevier Inc. All rights reserved.

An ultralow power athermal silicon modulator.

PubMed

Timurdogan, Erman; Sorace-Agaskar, Cheryl M; Sun, Jie; Shah Hosseini, Ehsan; Biberman, Aleksandr; Watts, Michael R

2014-06-11

Silicon photonics has emerged as the leading candidate for implementing ultralow power wavelength-division-multiplexed communication networks in high-performance computers, yet current components (lasers, modulators, filters and detectors) consume too much power for the high-speed femtojoule-class links that ultimately will be required. Here we demonstrate and characterize the first modulator to achieve simultaneous high-speed (25 Gb s(-1)), low-voltage (0.5 VPP) and efficient 0.9 fJ per bit error-free operation. This low-energy high-speed operation is enabled by a record electro-optic response, obtained in a vertical p-n junction device that at 250 pm V(-1) (30 GHz V(-1)) is up to 10 times larger than prior demonstrations. In addition, this record electro-optic response is used to compensate for thermal drift over a 7.5 °C temperature range with little additional energy consumption (0.24 fJ per bit for a total energy consumption below 1.03 J per bit). The combined results of highly efficient modulation and electro-optic thermal compensation represent a new paradigm in modulator development and a major step towards single-digit femtojoule-class communications.

Adaptive Statistical Iterative Reconstruction-V: Impact on Image Quality in Ultralow-Dose Coronary Computed Tomography Angiography.

PubMed

Benz, Dominik C; Gräni, Christoph; Mikulicic, Fran; Vontobel, Jan; Fuchs, Tobias A; Possner, Mathias; Clerc, Olivier F; Stehli, Julia; Gaemperli, Oliver; Pazhenkottil, Aju P; Buechel, Ronny R; Kaufmann, Philipp A

The clinical utility of a latest generation iterative reconstruction algorithm (adaptive statistical iterative reconstruction [ASiR-V]) has yet to be elucidated for coronary computed tomography angiography (CCTA). This study evaluates the impact of ASiR-V on signal, noise and image quality in CCTA. Sixty-five patients underwent clinically indicated CCTA on a 256-slice CT scanner using an ultralow-dose protocol. Data sets from each patient were reconstructed at 6 different levels of ASiR-V. Signal intensity was measured by placing a region of interest in the aortic root, LMA, and RCA. Similarly, noise was measured in the aortic root. Image quality was visually assessed by 2 readers. Median radiation dose was 0.49 mSv. Image noise decreased with increasing levels of ASiR-V resulting in a significant increase in signal-to-noise ratio in the RCA and LMA (P < 0.001). Correspondingly, image quality significantly increased with higher levels of ASiR-V (P < 0.001). ASiR-V yields substantial noise reduction and improved image quality enabling introduction of ultralow-dose CCTA.

Soft Phonon Modes Leading to Ultralow Thermal Conductivity and High Thermoelectric Performance in AgCuTe.

PubMed

Roychowdhury, Subhajit; Jana, Manoj K; Pan, Jaysree; Guin, Satya N; Sanyal, Dirtha; Waghmare, Umesh V; Biswas, Kanishka

2018-04-03

Crystalline solids with intrinsically low lattice thermal conductivity (κ L ) are crucial to realizing high-performance thermoelectric (TE) materials. Herein, we show an ultralow κ L of 0.35 Wm -1  K -1 in AgCuTe, which has a remarkable TE figure-of-merit, zT of 1.6 at 670 K when alloyed with 10 mol % Se. First-principles DFT calculation reveals several soft phonon modes in its room-temperature hexagonal phase, which are also evident from low-temperature heat-capacity measurement. These phonon modes, dominated by Ag vibrations, soften further with temperature giving a dynamic cation disorder and driving the superionic transition. Intrinsic factors cause an ultralow κ L in the room-temperature hexagonal phase, while the dynamic disorder of Ag/Cu cations leads to reduced phonon frequencies and mean free paths in the high-temperature rocksalt phase. Despite the cation disorder at elevated temperatures, the crystalline conduits of the rigid anion sublattice give a high power factor. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Association of Anterior Cruciate Ligament Width With Anterior Knee Laxity.

PubMed

Wang, Hsin-Min; Shultz, Sandra J; Schmitz, Randy J

2016-06-02

Greater anterior knee laxity (AKL) has been identified as an anterior cruciate ligament (ACL) injury risk factor. The structural factors that contribute to greater AKL are not fully understood but may include the ACL and bone geometry. To determine the relationship of ACL width and femoral notch angle to AKL. Cross-sectional study. Controlled laboratory. Twenty recreationally active females (age = 21.2 ± 3.1 years, height = 1.66.1 ± 7.3 cm, mass = 66.5 ± 12.0 kg). Anterior cruciate ligament width and femoral notch angle were obtained with magnetic resonance imaging of the knee and AKL was assessed. Anterior cruciate ligament width was measured as the width of a line that transected the ACL and was drawn perpendicular to the Blumensaat line. Femoral notch angle was formed by the intersection of the line parallel to the posterior cortex of the femur and the Blumensaat line. Anterior knee laxity was the anterior displacement of the tibia relative to the femur (mm) at 130 N of an applied force. Ten participants' magnetic resonance imaging data were assessed on 2 occasions to establish intratester reliability and precision. Using stepwise backward linear regression, we examined the extent to which ACL width, femoral notch angle, and weight were associated with AKL. Strong measurement consistency and precision (intraclass correlation coefficient [2,1] ± SEM) were established for ACL width (0.98 ± 0.3 mm) and femoral notch angle (0.97° ± 1.1°). The regression demonstrated that ACL width (5.9 ± 1.4 mm) was negatively associated with AKL (7.2 ± 2.0 mm; R(2) = 0.22, P = .04). Femoral notch angle and weight were not retained in the final model. A narrower ACL was associated with greater AKL. This finding may inform the development of ACL injury-prevention programs that include components designed to increase ACL size or strength (or both). Future authors should establish which other factors contribute to greater AKL in order to best inform injury-prevention efforts.

Reconstruction of an anterior chest wall radionecrosis defect by a contralateral latissimus dorsi flap: A case report.

PubMed

Vairinho, A; Al Hindi, A; Revol, M; Legras, A; Rem, K; Guenane, Y; Cristofari, S; Sorin, T

2018-04-01

Soft tissue and bone radionecrosis are rare but serious complications may occur late after radiotherapy. We report the case of an 86-year-old woman with a history an infiltrating ductal carcinoma of the left breast, treated by total mastectomy, left axillary dissection and adjuvant radiotherapy. Eighteen years later, the first radionecrosis lesions appeared and grew progressively in a 6-month period. These lesions are deep, involving the anterior aspect of the 4th to the 6th ribs and infiltrating the chest wall to the left cardio-thoracic space communicating largely with the pericardium. During axillary dissection, the neurovascular pedicle of the left latissimus dorsi muscle had been severed. The first part of the operation consisted of performing a left side parietectomy of the thoracic wall with a large resection of pericardial tissue and a small myocardial patch. The second step consisted of repairing the thoracic wall defect with a contralateral musculocutaneous latissimus dorsi flap. Due to its significant axis of rotation, the latissimus dorsi muscle flap must be considered in the therapeutic algorithm for covering of contralateral anterior chest wall defects. Copyright © 2018 Elsevier Masson SAS. All rights reserved.

Examination of cryogenic filters for multistage RF filtering in ultralow temperature experiments

NASA Astrophysics Data System (ADS)

Zavyalov, V. V.; Chernyaev, S. A.; Shein, K. V.; Shukaleva, A. G.; Arutyunov, K. Yu

2018-03-01

Cryo-filters are essential while studying electronic properties of nanoscale structures at very low temperatures. In this report we present the simple measuring methodology and experimental impedance characteristics of customized lumped filters cooled down to 4.2K in the 10 Hz-500 MHz frequency range. In particular, we tested the home-made permalloy-core RL filters, the MurataTMChip Ferrite Bead filter, and the ToshibaTMAmobeadsTMcores. We use the high-frequency generalization of four-terminal sensing method to account for the wiring retardation effects, which are important when working with ultralow temperature systems.

Ultralow-Power Electronic Trapping of Nanoparticles with Sub-10 nm Gold Nanogap Electrodes.

PubMed

Barik, Avijit; Chen, Xiaoshu; Oh, Sang-Hyun

2016-10-12

We demonstrate nanogap electrodes for rapid, parallel, and ultralow-power trapping of nanoparticles. Our device pushes the limit of dielectrophoresis by shrinking the separation between gold electrodes to sub-10 nm, thereby creating strong trapping forces at biases as low as the 100 mV ranges. Using high-throughput atomic layer lithography, we manufacture sub-10 nm gaps between 0.8 mm long gold electrodes and pattern them into individually addressable parallel electronic traps. Unlike pointlike junctions made by electron-beam lithography or larger micron-gap electrodes that are used for conventional dielectrophoresis, our sub-10 nm gold nanogap electrodes provide strong trapping forces over a mm-scale trapping zone. Importantly, our technology solves the key challenges associated with traditional dielectrophoresis experiments, such as high voltages that cause heat generation, bubble formation, and unwanted electrochemical reactions. The strongly enhanced fields around the nanogap induce particle-transport speed exceeding 10 μm/s and enable the trapping of 30 nm polystyrene nanoparticles using an ultralow bias of 200 mV. We also demonstrate rapid electronic trapping of quantum dots and nanodiamond particles on arrays of parallel traps. Our sub-10 nm gold nanogap electrodes can be combined with plasmonic sensors or nanophotonic circuitry, and their low-power electronic operation can potentially enable high-density integration on a chip as well as portable biosensing.

Pure laparoscopic radical resection for type IIIa hilar cholangiocarcinoma.

PubMed

Zhang, Cheng-Wu; Liu, Jie; Hong, De-Fei; Wang, Zhi-Fei; Hu, Zhi-Ming; Huang, Dong-Shen; Shang, Min-Jie; Yao, Wei-Feng

2018-03-01

Pure laparoscopic radical resection of hilar cholangiocarcinoma is still a challenging procedure, in which laparoscopic lymphadenectomy, hemihepatectomy with caudate lobectomy, and hepaticojejunostomy were included [1-4]. Relative report is rare in the world up to now. Hilar cholangiocarcinoma has a poor prognosis, especially when it occurs with lymph node metastasis or vessel invasion [5, 6]. We recently had a patient who underwent a pure laparoscopic extended right hepatectomy and lymph node dissection and hepaticojejunostomy for a type IIIa hilar cholangiocarcinoma. The tumor was 20 × 15 × 12 mm in diameter and located in the right bile duct and common hepatic duct. Radiological examination showed that hepatic artery and portal vein was not invaded. After the division and mutilation of the right hepatic artery and the right portal vein, short hepatic veins were divided and cut off with clip and ultrasound knife from the anterior face of the vena cava. Mobilization was performed after the devascularization of the right liver, followed by the transection of liver parenchymal with CUSA and ultrasound knife. Finally, left hepatic bile duct jejunum Roux-en-Y reconstruction was performed. This patient underwent successfully with a totally laparoscopic procedure. An extended right hepatectomy (right hemihepatectomy combined with caudate lobectomy) and complete lymph node dissection and hepaticojejunostomy were performed in this operation. The operation time was nearly 590 min, and the intraoperative blood loss was about 300 ml. No obvious complication was observed and the postoperative hospital stay was 11 days. The final diagnosis of the hilar cholangiocarcinoma with no lymph node metastasis was pT2bN0M0 stage II (American Joint Committee on Cancer, AJCC). Pure laparoscopic resection for hilar cholangiocarcinoma was proved safe and feasible, which enabled the patient to recover early and have an opportunity to receive chemotherapy as soon as possible. We

Can a curved stapler made for open surgery be useful in laparoscopic lower rectal resections? Technique and experience of a single centre.

PubMed

Mari, Francesco Saverio; Gasparrini, Marcello; Nigri, Giuseppe; Berardi, Giammauro; Laracca, Giovanni Guglielmo; Flora, Barbara; Pancaldi, Alessandra; Brescia, Antonio

2013-01-01

The use of laparoscopy to perform lower anterior rectal resection is increasing worldwide because it allows better visualisation and rectal mobilisation and also reduces postoperative pain and recovery. The Contour Curved Stapler (CCS) is a very helpful device because of its curved profile that enables better access into the pelvic cavity and allows rectal closure and section to be performed in one shot. In this paper, we present an original technique to use this device, made for open surgery, in laparoscopy and the results of our experience. We retrospectively evaluated the data of all patients who underwent lower laparoscopic anterior rectal resection and in which the CCS was used to perform section of the rectum between September 2005 and September 2011. To perform section of the rectum a Lapdisc(®) was inserted through a 6-7 cm supra-pubic midline incision to allow placement of the CCS into the pelvic cavity. Patients' biographical and surgical data such as sex, age, indication for surgery, infection, anastomotic leakage or stenosis and staple-line bleeding were prospectively collected in a computerised database and evaluated. Between September 2005 and September 2011, we performed 45 laparoscopic lower rectal resection using CCS, 27 male and 18 female with a mean age of 61 years (range 40-82 years) and a mean body mass index (BMI) of 26.5 kg/m(2) (range 16.5-35 kg/m(2)). In 29 cases a temporary ileostomy was performed. Mean operative time was 131 min (range 97-210 min). In all cases it was possible to perform a lower section of the rectum with CCS. No intraoperative or postoperative staple line bleeding occurred. In two patients we observed anastomotic leaks and in one of these a temporary ileostomy was performed. None of the patients showed an anastomotic stenosis at 1-year follow-up colonoscopy. This study shows that CCS enables section of the lower rectum to be easily performed, especially in adverse anatomical condition, and the technique proposed by us

Renal calculi in pregnancy? The role of ultralow-dose CT

PubMed Central

Nash, Zachary; Mascarenhas, Lawrence

2013-01-01

Presented is a case of an acute, right flank, loin to groin pain in the third trimester of an otherwise uncomplicated pregnancy. Renal calculi was suspected clinically and supported by radiological evidence. Temporising treatment was undertaken successfully by retrograde ureteric stenting, which became blocked, secondarily resulting in a percutaneous nephrostomy. Good symptomatic control was achieved before the delivery at 38 weeks and 1 day gestation. Postpartum intravenous urogram and ureteroscopy did not reveal evidence of calculi. The patient does not recall passing a stone. With existing diagnostic modalities having poor sensitivity and specificity, the clinical role of ultralow-dose CT is explored, in light of recent new evidence. PMID:23729704

Scheimpflug imaging in anterior megalophthalmos

PubMed Central

Nemeth, Gabor; Hassan, Ziad; Berta, Andras; Modis, Laszlo

2013-01-01

We report an anterior megalophthalmos case with decreased corneal thickness and show the findings using Scheimpflug imaging. A 25-year-old male was diagnosed with anterior megalophthalmos. In both eyes, enlarged corneal length was measured. Beside a comparatively good visual acuity, a thin but clear cornea, a fairly deep anterior chamber, and central lens opacity were found. Scheimpflug images were taken using Pentacam HR. Scheimpflug-based imaging can provide us new data at the examination of this syndrome affecting the whole anterior segment. PMID:23275220

Note: Expanding the bandwidth of the ultra-low current amplifier using an artificial negative capacitor.

PubMed

Xie, Kai; Liu, Yan; Li, XiaoPing; Guo, Lixin; Zhang, Hanlu

2016-04-01

The bandwidth and low noise characteristics are often contradictory in ultra-low current amplifier, because an inevitable parasitic capacitance is paralleled with the high value feedback resistor. In order to expand the amplifier's bandwidth, a novel approach was proposed by introducing an artificial negative capacitor to cancel the parasitic capacitance. The theory of the negative capacitance and the performance of the improved amplifier circuit with the negative capacitor are presented in this manuscript. The test was conducted by modifying an ultra-low current amplifier with a trans-impedance gain of 50 GΩ. The results show that the maximum bandwidth was expanded from 18.7 Hz to 3.3 kHz with more than 150 times of increase when the parasitic capacitance (∼0.17 pF) was cancelled. Meanwhile, the rise time decreased from 18.7 ms to 0.26 ms with no overshot. Any desired bandwidth or rise time within these ranges can be obtained by adjusting the ratio of cancellation of the parasitic and negative capacitance. This approach is especially suitable for the demand of rapid response to weak current, such as transient ion-beam detector, mass spectrometry analysis, and fast scanning microscope.

Non-invasive paper-based microfluidic device for ultra-low detection of urea through enzyme catalysis

NASA Astrophysics Data System (ADS)

Suresh, Vignesh; Qunya, Ong; Kanta, Bera Lakshmi; Yuh, Lee Yeong; Chong, Karen S. L.

2018-03-01

This work describes the design, fabrication and characterization of a paper-based microfluidic device for ultra-low detection of urea through enzyme catalysis. The microfluidic system comprises an entry port, a fluidic channel, a reaction zone and two electrodes (contacts). Wax printing was used to create fluidic channels on the surface of a chromatography paper. Pre-conceptualized designs of the fluidic channel are wax-printed on the paper substrate while the electrodes are screen-printed. The paper printed with wax is heated to cause the wax reflow along the thickness of the paper that selectively creates hydrophilic and hydrophobic zones inside the paper. Urease immobilized in the reaction zone catalyses urea into releasing ions and, thereby, generating a current flow between the electrodes. A measure of current with respect to time at a fixed potential enables the detection of urea. The methodology enabled urea concentration down to 1 pM to be detected. The significance of this work lies in the use of simple and inexpensive paper-based substrates to achieve detection of ultra-low concentrations of analytes such as urea. The process is non-invasive and employs a less cumbersome two-electrode assembly.

Impact of frailty on approach to colonic resection: Laparoscopy vs open surgery.

PubMed

Mosquera, Catalina; Spaniolas, Konstantinos; Fitzgerald, Timothy L

2016-11-21

To understand the influence of frailty on postoperative outcomes for laparoscopic and open colectomy. Data were obtained from the National Surgical Quality Improvement Program (2005-2012) for patients undergoing colon resection [open colectomy (OC) and laparoscopic colectomy (LC)]. Patients were classified as non-frail (0 points), low frailty (1 point), moderate frailty (2 points), and severe frailty (≥ 3) using the Modified Frailty Index. 30-d mortality and complications were used as the primary end point and analyzed for the overall population. Complications were grouped into major and minor. Subset analysis was performed for patients undergoing colectomy (total colectomy, partial colectomy and sigmoid colectomy) and separately for patients undergoing rectal surgery (abdominoperineal resection, low anterior resection, and proctocolectomy). We analyzed the data using SAS Platform JMP Pro version 10.0.0 (SAS Institute Inc., Cary, NC, United States). A total of 94811 patients were identified; the majority underwent OC (58.7%), were white (76.9%), and non-frail (44.8%). The median age was 61.3 years. Prolonged length of stay (LOS) occurred in 4.7%, and 30-d mortality was 2.28%. Patients undergoing OC were older (61.89 ± 15.31 vs 60.55 ± 14.93) and had a higher ASA score (48.3% ASA3 vs 57.7% ASA2 in the LC group) ( P < 0.0001). Most patients were non-frail (42.5% OC vs 48% LC, P < 0.0001). Complications, prolonged LOS, and mortality were significantly more common in patients undergoing OC ( P < 0.0001). OC had a higher risk of death and complications compared to LC for all frailty scores (non-frail: OR = 4.7, and OR = 4.67; mildly frail: OR = 2.51, and OR = 2.47; moderately frail: OR = 2.94, and OR = 2.02, severely frail: OR = 2.37, and OR = 2.34, P < 0.05) and an increase in absolute mortality with increasing frailty (non-frail 0.68% OC, mildly frail 1.39%, moderately frail 3.44%, and severely frail 5.83%, P < 0.0001). LC is associated with improved outcomes

Anterior Urethral Advancement as a Single-Stage Technique for Repair of Anterior Hypospadias: Our Experience.

PubMed

Gite, Venkat A; Nikose, Jayant V; Bote, Sachin M; Patil, Saurabh R

2017-07-02

Many techniques have been described to correct anterior hypospadias with variable results. Anterior urethral advancement as one stage technique was first described by Ti Chang Shing in 1984. It was also used for the repair of strictures and urethrocutaneous fistulae involving distal urethra. We report our experience of using this technique with some modification for the repair of anterior hypospadias. In the period between 2013-2015, 20 cases with anterior hypospadias including 2 cases of glanular, 3 cases of coronal, 12 cases of subcoronal and 3 cases of distal penile hypospadias were treated with anterior urethral advancement technique. Patients' age groups ranged from 18 months to 10 years. Postoperatively, patients were passing urine from tip of neomeatus with satisfactory stream during follow up period of 6 months to 2 years. There were no major complications in any of our patients except in one patient who developed meatal stenosis which was treated by periodic dilatation. Three fold urethral mobilization was sufficient in all cases. Anterior urethral advancement technique is a single-stage procedure with good cosmetic results and least complications for anterior hypospadias repair in properly selected cases.

ERASE-Seq: Leveraging replicate measurements to enhance ultralow frequency variant detection in NGS data

PubMed Central

Kamps-Hughes, Nick; McUsic, Andrew; Kurihara, Laurie; Harkins, Timothy T.; Pal, Prithwish; Ray, Claire

2018-01-01

The accurate detection of ultralow allele frequency variants in DNA samples is of interest in both research and medical settings, particularly in liquid biopsies where cancer mutational status is monitored from circulating DNA. Next-generation sequencing (NGS) technologies employing molecular barcoding have shown promise but significant sensitivity and specificity improvements are still needed to detect mutations in a majority of patients before the metastatic stage. To address this we present analytical validation data for ERASE-Seq (Elimination of Recurrent Artifacts and Stochastic Errors), a method for accurate and sensitive detection of ultralow frequency DNA variants in NGS data. ERASE-Seq differs from previous methods by creating a robust statistical framework to utilize technical replicates in conjunction with background error modeling, providing a 10 to 100-fold reduction in false positive rates compared to published molecular barcoding methods. ERASE-Seq was tested using spiked human DNA mixtures with clinically realistic DNA input quantities to detect SNVs and indels between 0.05% and 1% allele frequency, the range commonly found in liquid biopsy samples. Variants were detected with greater than 90% sensitivity and a false positive rate below 0.1 calls per 10,000 possible variants. The approach represents a significant performance improvement compared to molecular barcoding methods and does not require changing molecular reagents. PMID:29630678

Ultralow crosstalk nanosecond-scale nested 2 × 2 Mach-Zehnder silicon photonic switch.

PubMed

Dupuis, Nicolas; Rylyakov, Alexander V; Schow, Clint L; Kuchta, Daniel M; Baks, Christian W; Orcutt, Jason S; Gill, Douglas M; Green, William M J; Lee, Benjamin G

2016-07-01

We present the design and characterization of a novel electro-optic silicon photonic 2×2 nested Mach-Zehnder switch monolithically integrated with a CMOS driver and interface logic. The photonic device uses a variable optical attenuator in order to balance the power inside the Mach-Zehnder interferometer leading to ultralow crosstalk performance. We measured a crosstalk as low as -34.5  dB, while achieving ∼2  dB insertion loss and 4 ns transient response.

A fast- and positively photoswitchable fluorescent protein for ultralow-laser-power RESOLFT nanoscopy.

PubMed

Tiwari, Dhermendra K; Arai, Yoshiyuki; Yamanaka, Masahito; Matsuda, Tomoki; Agetsuma, Masakazu; Nakano, Masahiro; Fujita, Katsumasa; Nagai, Takeharu

2015-06-01

Fluorescence nanoscopy has revolutionized our ability to visualize biological structures not resolvable by conventional microscopy. However, photodamage induced by intense light exposure has limited its use in live specimens. Here we describe Kohinoor, a fast-switching, positively photoswitchable fluorescent protein, and show that it has high photostability over many switching repeats. With Kohinoor, we achieved super-resolution imaging of live HeLa cells using biocompatible, ultralow laser intensity (0.004 J/cm(2)) in reversible saturable optical fluorescence transition (RESOLFT) nanoscopy.

Circuit design advances for ultra-low power sensing platforms

NASA Astrophysics Data System (ADS)

Wieckowski, Michael; Dreslinski, Ronald G.; Mudge, Trevor; Blaauw, David; Sylvester, Dennis

2010-04-01

This paper explores the recent advances in circuit structures and design methodologies that have enabled ultra-low power sensing platforms and opened up a host of new applications. Central to this theme is the development of Near Threshold Computing (NTC) as a viable design space for low power sensing platforms. In this paradigm, the system's supply voltage is approximately equal to the threshold voltage of its transistors. Operating in this "near-threshold" region provides much of the energy savings previously demonstrated for subthreshold operation while offering more favorable performance and variability characteristics. This makes NTC applicable to a broad range of power-constrained computing segments including energy constrained sensing platforms. This paper explores the barriers to the adoption of NTC and describes current work aimed at overcoming these obstacles in the circuit design space.

Ileocolic junction resection in dogs and cats: 18 cases.

PubMed

Fernandez, Yordan; Seth, Mayank; Murgia, Daniela; Puig, Jordi

2017-12-01

There is limited veterinary literature about dogs or cats with ileocolic junction resection and its long-term follow-up. To evaluate the long-term outcome in a cohort of dogs and cats that underwent resection of the ileocolic junction without extensive (≥50%) small or large bowel resection. Medical records of dogs and cats that had the ileocolic junction resected were reviewed. Follow-up information was obtained either by telephone interview or e-mail correspondence with the referring veterinary surgeons. Nine dogs and nine cats were included. The most common cause of ileocolic junction resection was intussusception in dogs (5/9) and neoplasia in cats (6/9). Two dogs with ileocolic junction lymphoma died postoperatively. Only 2 of 15 animals, for which long-term follow-up information was available, had soft stools. However, three dogs with suspected chronic enteropathy required long-term treatment with hypoallergenic diets alone or in combination with medical treatment to avoid the development of diarrhoea. Four of 6 cats with ileocolic junction neoplasia were euthanised as a consequence of progressive disease. Dogs and cats undergoing ileocolic junction resection and surviving the perioperative period may have a good long-term outcome with mild or absent clinical signs but long-term medical management may be required.

Small bowel resection - slideshow

MedlinePlus

... this page: //medlineplus.gov/ency/presentations/100039.htm Small bowel resection - series—Normal anatomy To use the ... to slide 5 out of 5 Overview The small intestine absorbs much of the liquid from foods. ...

Endoscopic full-thickness resection of gastric subepithelial tumors: a single-center series.

PubMed

Schmidt, Arthur; Bauder, Markus; Riecken, Bettina; von Renteln, Daniel; Muehleisen, Helmut; Caca, Karel

2015-02-01

Endoscopic full-thickness resection of gastric subepithelial tumors with a full-thickness suturing device has been described as feasible in two small case series. The aim of this study was to evaluate the efficacy, safety, and clinical outcome of this resection technique. After 31 patients underwent endoscopic full-thickness resection, the data were analyzed retrospectively. Before snare resection, 1 to 3 full-thickness sutures were placed underneath each tumor with a device originally designed for endoscopic anti-reflux therapy. All tumors were resected successfully. Bleeding occurred in 12 patients (38.7 %); endoscopic hemostasis could be achieved in all cases. Perforation occurred in 3 patients (9.6 %), and all perforations could be managed endoscopically. Complete resection was histologically confirmed in 28 of 31 patients (90.3 %). Mean follow-up was 213 days (range, 1 - 1737), and no tumor recurrences were observed. Endoscopic full-thickness resection of gastric subepithelial tumors with the suturing technique described above is feasible and effective. After the resection of gastrointestinal stromal tumors (GISTs), we did not observe any recurrences during follow-up, indicating that endoscopic full-thickness resection may be an alternative to surgical resection for selected patients. © Georg Thieme Verlag KG Stuttgart · New York.

Biopsy forceps is inadequate for the resection of diminutive polyps.

PubMed

Efthymiou, M; Taylor, A C; Desmond, P V; Allen, P B; Chen, R Y

2011-04-01

Cold biopsy forceps polypectomy (CBP) is often used for the removal of diminutive polyps. The efficacy of the technique has not been thoroughly assessed. The aim of this study was to prospectively assess the efficacy of CBP for removing diminutive polyps. This was a prospective study from St Vincent's Hospital, a tertiary referral hospital in Melbourne, Australia. A total of 143 patients were screened and 52 patients with ≥ 1 diminutive polyps were enrolled. CBP was used to resect diminutive polyps until no polyp tissue was visible. The polyp base was then resected using endoscopic mucosal resection (EMR) with a 1 - 2-mm margin. The CBP and EMR samples were compared to assess completeness of the resection. Overall 39 % (21 / 54) of diminutive polyps were completely resected using CBP. After binary logistic regression analysis, polyp histology was found to be predictive of resection, with complete resection of 62 % (13 / 21) for adenomas and 24 % (8 / 33) for hyperplastic polyps (odds ratio 5.1; P = 0.008). The size and number of bites taken with the forceps were not predictive of complete response. Within the limitations of a modest sample size, CBP appears to be inadequate treatment for the removal of diminutive polyps. © Georg Thieme Verlag KG Stuttgart · New York.

Pleomorphic rhabdomyosarcoma arising in the anterior mediastinum: A case report with cytological features of imprint and liquid-based cytology specimens.

PubMed

Nishijima, Yoshimi; Hirato, Junko; Fukuda, Toshio

2017-04-01

We herein report the cytological features of a very rare case of pleomorphic rhabdomyosarcoma arising in the anterior mediastinum on imprint and liquid-based cytology (LBC) specimens. A 58-year-old man had an approximately 10-cm tumor in the anterior mediastinum as shown on computed tomography. Thymectomy with complete resection of the left lung was performed. The fresh cut surface of the tumor was used to prepare imprint and LBC specimens. The imprint specimens showed four types of tumor cells dispersed on a background of hemorrhage, necrosis, and mucus. On the other hand, only two types of tumor cells (spindle-shaped and spiderweb cells) were scattered or present in clusters in the LBC specimens. Immunocytologically, both of these cell types were positive for desmin and myoglobin, negative for pan-keratin and epithelial membrane antigen. Cytological and immunocytological features are useful for the correct diagnosis of pleomorphic rhabdomyosarcoma, and LBC specimens show clearer results than do imprint specimens. Diagn. Cytopathol. 2017;45:333-338. © 2016 Wiley Periodicals, Inc. © 2016 Wiley Periodicals, Inc.

Use of the circular compression stapler and circular mechanical stapler in the end-to-side transanal colorectal anastomosis after left colon and rectal resections A single center experience.

PubMed

Pironi, Daniele; Vendettuoli, Maurizio; Pontone, Stefano; Panarese, Alessandra; Arcieri, Stefano; Filippini, Angelo; Grimaldi, Gianmarco

2016-01-01

The aim of our study was to compare the efficacy of the circular compression stapler and the circular mechanical stapler in transanal colorectal anastomosis after left colectomy or anterior rectal resection. We performed a retrospective analysis of 10 patients with disease of the, sigmoid colon or rectum (carcinoma or diverticular disease) who underwent left colectomy or anterior rectal resection with end-to-side transanal colorectal anastomosis. A follow-up was planned for all patients at 1, 3 and 6 months after surgery and the anastomosis was evaluated by colonoscopy at 1 year. In all patients an end-to-side transanal colorectal anastomosis was performed using a circular compression stapler (CCS group) or circular mechanical staplers with titanium staples (CMS group). The mean distance of the anastomosis from the anal margin was 6.4 ± 1.5 cm in the CCS group and 18.2 ± 11.2 cm in the CMS group. All patients in the CCS group expelled the ring after a mean time of 8.2 postoperative days. At 12 months colonoscopy revealed that all CCS patients had a satisfactory anastomosis with mean size of the colic lumen at the level of anastomotic line of 26.3 mm. In our experience the circular compression stapler a valuable alternative to the circular mechanical stapler for the creation of transanal colorectal anastomosis, in line with the relevant literature. Anastomotic leakage, Anastomotic stenosis, Circular compression stapler, Circular mechanical stapler, Transanal colorectal anastomosis.

Superior interhemispheric approach for midline meningioma from the anterior cranial base.

PubMed