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Technical Failure (technical + failure)
Selected AbstractsCyanoacrylate embolization of endoleaks after abdominal aortic aneurysm repairANZ JOURNAL OF SURGERY, Issue 11 2009Timothy Buckenham Abstract Introduction:, Type II endoleaks occur in up to a fifth of endoluminal repairs for abdominal aortic aneurysms and are commonly treated when aortic sac expansion can be demonstrated. Technical failure is common when catheter-guided particulates or coil embolic agents are used. Presented here is a feasibility study using catheter-directed N-butyl-2-cyanoacrylate (Histoacryl, Braun, Tuttlingen, Germany) embolotherapy. Method:, A retrospective review of the case notes of patients undergoing embolization procedures for type II endoleaks with expanding sacs was performed from this centre's cohort of endoluminal aortic repair patients under surveillance. Data on patients with type II endoleaks who were treated with either or both cyanoacrylate and coil embolization were extracted. The outcomes were then compared. Results:, In total, five cases were identified, and four of these cases had both coil and glue embolization. Technical success was defined as endoleak closure proven on follow-up computed tomographic imaging. Technical success was achieved in all four patients treated with intra-sac cyanoacrylate. One case treated initially with coil embolization was successful. All patients had a computed tomographic scan at 3 months. One minor complication occurred that resolved without treatment. Discussion:, Type II endoleaks after EVAR with expanding sacs require treatment. Percutaneous catheter-directed cyanoacrylate embolization offers an alternative to coil or particulate embolization and, in this series, was found to be more likely to result in endoleak closure. [source] Anatomical basis for a successful upper limb sympathectomy in the thoracoscopic eraCLINICAL ANATOMY, Issue 4 2004L. Ramsaroop Abstract In this clinico-anatomical study, factors potentially responsible for unsuccessful upper limb sympathectomy (ULS) by the thoracoscopic route were evaluated. This study comprised two subsets: 1) in the clinical subset, 25 patients (n = 50 sides) underwent bilateral second thoracic ganglionectomy for palmar hyperhidrosis, and factors predisposing to unsuccessful ULS were identified; and 2) in the anatomical subset, the neural connections of the first and second intercostal spaces were bilaterally dissected in 22 adult cadavers (22 right, 21 left; n = 43 sides). Alternate neural pathways (ANP) were noted in 9 of 50 sides in the 25 clinical cases (18%). In three asthenic patients (5 sides), fascia overlying the longus colli muscle mimicked the sympathetic chain. The right superior intercostal vein (SIV) was located anterior to the second thoracic ganglion in 6 of 50 sides (12%) and predisposed to troublesome bleeding in 2 of 50 cases; the SIV was posterior to the ganglion in 19 of 50 sides (38%), posing no technical problem. On the left, the SIV was noted outside the field of dissection in all but one case. A successful outcome to sympathectomy was noted in all 25 patients. A spectrum of sympathetic contributions to the first thoracic ventral ramus for the first intercostal space was noted in 37 of 43 anatomical cases (86%). These were categorized according to the arrangements of the intrathoracic ramus between the second intercostal nerve and the first thoracic ventral ramus. The cervicothoracic ganglion (37/43 cases; 86%) and an independent inferior cervical ganglion (6/43 cases; 14%) were always located above the second rib. The second thoracic ganglion was consistently located in the second intercostal space. This study demonstrates that ANPs have little clinical significance when a second thoracic ganglionectomy is undertaken. Technical failures may be avoided if the surgeon is mindful of anatomical variations at surgery. Clin. Anat. 17:294,299, 2004. © 2004 Wiley-Liss, Inc. [source] Self expanding wall stents in malignant colorectal cancer: is complete obstruction a contraindication to stent placement?COLORECTAL DISEASE, Issue 8 2009G. J. A. Stenhouse Abstract Objective, Technical failures have previously been associated with complete clinical obstruction and complete block to the retrograde flow of gastrograffin is considered by some to be a contraindication to the procedure. We report on the technical and clinical success rates of self-expanding metallic stents (SEMS) in both complete and incomplete obstruction in a prospective series of malignant colorectal obstructions. Method, A prospective study of all patients undergoing attempted palliative and bridge to surgery SEMS placement for malignant colorectal obstruction over a 7-year period (April 1999,October 2006) was undertaken. Results, Seventy-two patients (49 males) with a mean age of 71 years (range 49,98) were included. Technical success was achieved in 27 of 32 patients (84%) with complete obstruction and 33 of 36 patients (92%) with incomplete obstruction, P < 0.46, Fishers exact test. Clinical success was achieved in 17 of 26 patients (65%) with complete obstruction and 24 of 33 patients (73%) with incomplete obstruction, P < 0.58, Fishers exact test. Although placed correctly in 89% cases, relief of symptoms occurred in only 71%, P = 0.002, matched pairs test. There were two colonic perforations in the series with one procedure related death. Conclusion, Placement of SEMS for obstructing colorectal cancer is technically successful in a high proportion of cases. Complete radiological obstruction is not a contraindication to stent placement. The relief of obstructive symptoms following successful placement of a wall stent is less predictable. [source] Fluoroscopy-Guided Endovenous Foam Sclerotherapy Using a Microcatheter in Varicose Tributaries Followed by Endovenous Laser Treatment of Incompetent Saphenous Veins: Technical Feasibility and Early ResultsDERMATOLOGIC SURGERY, Issue 5 2009SANG WOO PARK MD OBJECTIVES To evaluate the technical feasibility and preliminary results of endovenous foam sclerotherapy using a microcatheter in varicose tributaries followed by endovenous laser treatment (EVLT) of incompetent saphenous veins. MATERIALS AND METHODS From July 2005 to August 2006, 312 patients (M:F=139:173, mean age 45.8) who presented with varicose veins with reflux in the saphenofemoral, saphenopopliteal junction or tributaries were enrolled. Under ultrasound or fluoroscopy guidance, selective microcatheterization and endovenous foam slcerotherapy were first performed in varicose tributaries, followed by EVLT (980 nm) of incompetent saphenous veins. Follow-up at 1-week and 1-, 3-, and 6-month intervals was done. RESULTS Technical success was seen in 410 of 411 limbs (99%). Continued closure of the saphenous veins and the complete sclerosis of varicose tributaries were noted in 332 of 373 limbs (89%) at the 1-month follow-up, all 307 limbs (100%) at the 3-month follow-up, and all 274 limbs (100%) at the 6-month follow-up. No serious complication was noted. CONCLUSION Endovenous foam sclerotherapy using a microcatheter in varicose tributaries followed by EVLT in incompetent saphenous veins is a safe, effective, and technically feasible treatment for varicose veins. It not only reduces additional sclerotherapy and technical failure, but also makes multiple therapeutic sessions unnecessary. [source] Sunscreens: expectation and realizationPHOTODERMATOLOGY, PHOTOIMMUNOLOGY & PHOTOMEDICINE, Issue 5 2009Brian Diffey Background: The technical performance of sunscreens has improved dramatically over the past 20 years, so have we now succeeded in delivering protection that meets consumers' expectations? Methods: From a public health perspective, the desire to prevent sunburn and protect against skin cancer are the two major drivers for using sunscreen. This review examines how well consumers can expect to realize these expectations. Results: Sunscreens are used regularly by a minority of people, even during recreational summer exposure. The failure of sunscreen to prevent sunburn is almost always due to the way that sunscreens are applied rather than technical failure of the product. The mismatch between the labelled protection (sun protection factor) and that delivered in practice is a contributory factor to this ,failure'. Sunscreens have been shown to be effective in reducing the incidence of squamous cell cancer and with promising benefits for basal cell cancer. However, the evidence that they are effective in melanoma remains lacking. Conclusion: The formulation and extinction of sunscreens have undoubtedly improved over recent years. Yet the notion that sunscreens provide unequivocal protection against the deleterious effects of sun exposure by everyone who uses them remains elusive. [source] From experience: Capturing hard-won NPD lessons in checklistsTHE JOURNAL OF PRODUCT INNOVATION MANAGEMENT, Issue 5 2001Raymond F. Riek The application of a good New Product Development (NPD) process is frequently limited by the experience of the user. Avoiding relatively minor errors and omissions that can lead to seriously flawed project results is still an art. Checklists for each stage of a development project can capture this art and their disciplined use can avoid many potentially critical omissions and errors. Development of checklists frequently comes from the hard experiences many of us have had in bringing new products to market. Consequently, benchmarking "trials and tribulations" rather than success stories can be more appropriate to developing a thoughtful checklist. This article is a partial accumulation of one practitioner's experiences of over three decades of executing, managing, directing and observing these projects. Fifteen NPD case histories are examined to develop learnings from these experiences. These cases are organized around three basic product development issues: managing technical risks, managing commercial risks, and managing NPD personnel. In these examples, NPD project problems have a common theme of poor technical or commercial risk management, as opposed to technical failure. Improved planning and a more disciplined management interface would have avoided many of the problems discussed in these case histories. Analysis of each of the case histories and learnings is provided from which suggested checklist items are derived. These checklist additions are presented by development stage to allow use by other NPD teams, with the intention of avoiding the repetition of similar problems. [source] Vascular Stents in the Management of Portal Venous Complications in Living Donor Liver TransplantationAMERICAN JOURNAL OF TRANSPLANTATION, Issue 5 2010Y.-F. Cheng To evaluate the efficacy of stent placement in the treatment of portal vein (PV) stenosis or occlusion in living donor liver transplant (LDLT) recipients, 468 LDLT records were reviewed. Sixteen (10 PV occlusions and 6 stenoses) recipients (age range, 8 months,59 years) were referred for possible interventional angioplasty (dilatation and/or stent) procedures. Stent placement was attempted in all. The approaches used were percutaneous transhepatic (n = 10), percutaneous transsplenic (n = 4), and intraoperative (n = 2). Technical success was achieved in 11 of 16 patients (68.8%). The sizes of the stents used varied from 7 mm to 10 mm in diameter. In the five unsuccessful patients, long-term complete occlusion of the PV with cavernous transformation precluded catherterization. The mean follow-up was 12 months (range, 3,24). The PV stent patency rate was 90.9% (10/11). Rethrombosis and occlusion of the stent and PV occurred in a single recipient who had a cryoperserved vascular graft to reconstruct the PV during the LDLT operation. PV occlusion of >1 year with cavernous transformation seemed to be a factor causing technical failure. In conclusion, early treatment of PV stenosis and occlusion by stenting is an effective treatment in LDLT. Percutaneous transhepatic and transsplenic, and intraoperative techniques are effective approaches depending on the situation. [source] Postoperative pain relief using thoracic epidural analgesia: outstanding success and disappointing failuresANAESTHESIA, Issue 1 2001G. A. McLeod Six hundred and forty patients received epidural analgesia for postoperative pain relief following major surgery in the 6-year period 1993,1998. Although satisfactory pain relief was achieved in over two-thirds of patients for a median duration of 44 h after surgery, one-fifth of patients (133 individuals) still experienced poor pain relief. Almost one out of three patients (194 individuals) had a problem with their epidural. Eighty-three patients (13%) suffered a technical failure and 84 (13%) patients had their epidurals removed at night time when pain-free because of pressure on beds. Seven patients had their epidural replaced and subsequently experienced excellent pain relief for a median of 77 h. Lack of resources prevented a further 480 patients from receiving the potential benefits of epidural analgesia. These results would suggest that the practical problems of delivering an epidural service far outweigh any differences in drug regimens or modes of delivery of epidural solutions. [source] Real-world bare metal stenting: Identification of patients at low or very low risk of 9-month coronary revascularizationCATHETERIZATION AND CARDIOVASCULAR INTERVENTIONS, Issue 2 2004Stephen G. Ellis MD Abstract The high cost of drug-eluting stents (DESs) has made identification of patients who are at low risk for subsequent revascularization after treatment with bare metal stents (BMSs) highly desirable. Previous reports from randomized trials suffer from biases induced by restricted entry criteria and protocol-mandated angiographic follow-up. Between 1994 and 2001, 5,239 consecutive BMS patients, excluding those with coil stents, technical failure, brachytherapy, staged procedure, or stent thrombosis within 30 days, were prospectively identified from a large single-center tertiary-referral-center prospective registry for long-term follow-up. We sought to identify characteristics of patients with very low (, 4%) or low (4,10%) likelihood of coronary revascularization 9 months after BMS. Nine-month clinical follow-up was obtained in 98.2% of patients. Coronary revascularization was required in 13.4% and did not differ significantly by stent type. On the basis of multivariate analysis identifying 11 independent correlates and previous reports, 20 potential low-risk patient and lesion groups (228 ± 356 patients/groups) were identified (e.g, patients with all of the following: native vessel, de novo, reference diameter , 3.5 mm, lesion length < 5 mm, no diabetes, not ostial in location). Actual and model-based outcomes were analyzed. No group had both predicted and observed 9-month revascularization , 4% (very low risk). Conversely, 19 of 20 groups had a predicted and observed revascularization rate of 4,10% (low risk). In the real-world setting, the need for intermediate-term revascularization after BMS may be lower than expected, but it may be very difficult to identify patients at very low risk. Conversely, if the benefits of DESs are attenuated in routine practice, many groups of patients treated with BMSs may have nearly comparable results. Catheter Cardiovasc Interv 2004;63:135,140. © 2004 Wiley-Liss, Inc. [source] The pancreas allograft donor: current status, controversies, and challenges for the futureCLINICAL TRANSPLANTATION, Issue 4 2010Jonathan A. Fridell Fridell JA, Rogers J, Stratta RJ. The pancreas allograft donor: current status, controversies, and challenges for the future. Clin Transplant 2010: 24: 433,449. © 2010 John Wiley & Sons A/S. Abstract:, The pancreas allograft is a scarce resource that is currently underutilized. The selection of appropriate deceased donors for pancreas procurement is of paramount importance for minimizing technical failure and optimizing long-term outcomes in pancreas transplantation. Despite the increasing demand for pancreas transplantation, increases in overall organ donation rates and the evolution of criteria that constitute an "acceptable" pancreas donor, the number of deceased donor pancreas transplants being performed in the United States has actually declined in recent years. Although there are many factors that must be considered during evaluation of the potential pancreas allograft donor to minimize morbidity and graft loss, it is evident that there are transplantable organs that are not used. In this review, deceased donor pancreas identification, management, selection, allocation, assessment, preservation, and the problem of pancreas underutilization will be discussed. [source] A comparative evaluation of digital imaging, retinal photography and optometrist examination in screening for diabetic retinopathyDIABETIC MEDICINE, Issue 7 2003J. A. Olson Abstract Aims To compare the respective performances of digital retinal imaging, fundus photography and slit-lamp biomicroscopy performed by trained optometrists, in screening for diabetic retinopathy. To assess the potential contribution of automated digital image analysis to a screening programme. Methods A group of 586 patients recruited from a diabetic clinic underwent three or four mydriatic screening methods for retinal examination. The respective performances of digital imaging (n = 586; graded manually), colour slides (n = 586; graded manually), and slit-lamp examination by specially trained optometrists (n = 485), were evaluated against a reference standard of slit-lamp biomicroscopy by ophthalmologists with a special interest in medical retina. The performance of automated grading of the digital images by computer was also assessed. Results Slit-lamp examination by optometrists for referable diabetic retinopathy achieved a sensitivity of 73% (52,88) and a specificity of 90% (87,93). Using two-field imaging, manual grading of red-free digital images achieved a sensitivity of 93% (82,98) and a specificity of 87% (84,90), and for colour slides, a sensitivity of 96% (87,100) and a specificity of 89% (86,91). Almost identical results were achieved for both methods with single macular field imaging. Digital imaging had a lower technical failure rate (4.4% of patients) than colour slide photography (11.9%). Applying an automated grading protocol to the digital images detected any retinopathy, with a sensitivity of 83% (77,89) and a specificity of 71% (66,75) and diabetic macular oedema with a sensitivity of 76% (53,92) and a specificity of 85% (82,88). Conclusions Both manual grading methods produced similar results whether using a one- or two-field protocol. Technical failures rates, and hence need for recall, were lower with digital imaging. One-field grading of fundus photographs appeared to be as effective as two-field. The optometrists achieved the lowest sensitivities but reported no technical failures. Automated grading of retinal images can improve efficiency of resource utilization in diabetic retinopathy screening. Diabet. Med. 20, 528,534 (2003) [source] Laser-assisted endoscopic third ventriculostomy for obstructive hydrocephalus: Technique and results in a series of 40 consecutive casesLASERS IN SURGERY AND MEDICINE, Issue 5 2004Bertrand C. Devaux MD Abstract Background and Objectives To report a case series of endoscopic third ventriculostomy (ETV) using laser in 40 consecutive patients with obstructive hydrocephalus. Study Design/Materials and Methods Under stereotactic and endoscopic guidance, multiple perforations in the ventricular floor using a 1.32 ,m neodymium,yttrium/aluminum/garnet (Nd,YAG) or a 0.805 ,m diode laser unit and removal of intervening coagulated tissue ensued with a 4,6 mm opening between third ventricle and basilar cisterns. Results The procedure could be completed in all cases. A transient complication occurred in five cases. In 39 patients (mean follow-up 28 months), 31 (79%) had a favorable outcome. Failure occurred in six patients, requiring permanent shunting leading to complete recovery, and two patients remained in a poor clinical status despite ETV. Conclusions Laser-assisted ETV is a safe and efficient procedure for the treatment of obstructive hydrocephalus. Laser is advantageous in cases of distorted anatomy and may reduce technical failures. Lasers Surg. Med. 34:368,378, 2004. © 2004 Wiley-Liss, Inc. [source] External quality assessment of rapid prenatal detection of numerical chromosomal aberrations using molecular genetic techniques: 3 years experiencePRENATAL DIAGNOSIS, Issue 5 2007S. C. Ramsden Abstract Objectives Prenatal diagnosis using rapid molecular genetic techniques is now a widely used method for detecting the most prevalent chromosomal aneuploidies. The object of this work was to develop a methodology for delivering external quality assessment (EQA) appropriate to the needs of routine diagnostic testing laboratories. Methods We have provided three rounds of EQA using 15 different samples over 3 years. The scheme has developed to assess both the genotyping accuracy of the results and the appropriateness of the clinical reports issued to the referring clinician. Results Participation in the EQA scheme has increased from 9 to 27 laboratories from across Europe over the three sample distributions. All laboratories have used quantitative fluorescence-PCR (QF-PCR) to analyse these samples except for a sole participant in 2006 who used multiplex ligation-dependent probe amplification (MLPA). In total 265 samples have been distributed, of which four (1.5%) were not reported due to technical failures and one (0.4%) was reported incorrectly and must be regarded as a genotyping error. Conclusions We have demonstrated a significant and increasing demand for EQA in the rapid detection of aneuploidies in UK and other European laboratories. Using the methodologies described, we have had a very low rate of technical failures and demonstrated a high level of genotyping accuracy. However, the quality of the clinical reports was variable and suggestions are made for improvement. Copyright © 2007 John Wiley & Sons, Ltd. [source] | ||||||||||||||||||||||