Use of pre-operative Tc99m-Sestamibi scintigraphy and intraoperative parathyroid hormone monitoring to eliminate neck exploration in mediastinal parathyroid adenocarcinoma

A 66-year-old white woman was found to have an elevated serum calcium and parathyroid hormone (PTH) on routine health evaluation. Physical examination was unremarkable as was ultrasonography of the neck. A sestamibi parathyroid scan revealed abnormal uptake in the anterior mediastinum. Computed tomography of the chest demonstrated an anterior mediastinal mass compatible with a parathyroid adenoma but no neck masses. The patient underwent mediastinoscopy that was converted to a median sternotomy to fully access the mass. The mass was completely resected with surrounding thymus gland. Frozen section confirmed that excised tissue was parathyroid gland in origin. An intraoperative PTH obtained 20 minutes after specimen removal showed a decrease of more than 50% from preoperative levels. The strategy for initial surgery for hyperparathyroidism when a sestamibi scan is "positive" in the mediastinum (only) is a point of some controversy. Traditional recommendations have been to "clear the neck" of abnormal parathyroid tissue before undertaking a more morbid sternotomy. Mediastinoscopy was attempted to remove the mediastinal lesion and to avoid a sternotomy. Preoperative Tc99m sestamibi scintigraphy, frozen section histology, and intraoperative PTH monitoring permitted the authors to conclude that neck exploration was unnecessary.     

Intramedullary strut substitution and impaction allografting cemented revision for the treatment of a periprosthetic fracture in a severely compromised femur

Revision for the treatment of a B3 periprosthetic femoral fracture often requires proximal femoral allograft arthroplasty in physiologically young or tumor prostheses in elderly patients. Extramedullary strut allograft augmentation can only be used when the host femur is structurally adequate for the insertion of the revision stem (periprosthetic femoral fractures type B2) and appears to be an attractive biological concept as early incorporation to the host bone results in a sound biomechanical construct. We report here the simultaneous use of whole femur intramedullary strut substitution along with an extramedullary strut graft placement, with impaction allografting revision to a long cemented femoral prosthesis, to augment the deficient metadiaphyseal bone stock (Paprosky type IV) for the treatment of a complex type B3 periprosthetic femoral fracture.     

Anatomy of the pectoralis minor tendon and its use in acromioclavicular joint reconstruction

Many procedures described for operative management of acromioclavicular joint separations entail transfer of the coracoacromial ligament. We sought to describe the anatomy and morphology of the pectoralis minor tendon better, to assess its anatomic potential as a substitute for sacrificing the coracoacromial ligament, and to compare the ultimate tensile strength of the pectoralis minor with that of the coracoacromial ligament and detached coracoclavicular ligament. The morphology of the pectoralis minor tendon was carefully delineated and compared with that of the coracoacromial ligament, and 10 paired fresh-frozen cadaveric shoulders were tested to failure by applying a single uniaxial tensile load. Anatomic study of the pectoralis minor tendon confirmed its adequacy as a source of local autograft tissue in acromioclavicular joint reconstruction. We hypothesize that, in cases of acromioclavicular joint separation necessitating operative intervention, the use of the pectoralis minor tendon as a potential source of autograft tissue is anatomically feasible and it is slightly stronger than the coracoacromial ligament.     

Frontiers in nephrology: early atherosclerosis--a view beyond the lumen

Endothelial dysfunction is an established clinical marker of early coronary artery disease and has been shown to be associated with increased cardiovascular morbidity and mortality. New concepts now extend the view of endothelial dysfunction beyond the traditional involvement of the coronary arterial endothelium alone. Recent research indicates that the coronary vessel wall, especially the vasa vasorum, as well as bone marrow-derived endothelial progenitor cells may be subject to proatherosclerotic changes, even before the development of angiographically evident endothelial dysfunction; therefore, "microvascular endothelial dysfunction," which is composed of dysfunction of the vasa vasorum's endothelium as well as "microcellular endothelial dysfunction," reflecting impaired mobilization and function of endothelial progenitor cells, may precede "macrovascular endothelial dysfunction." Vasa vasorum neovascularization, with endothelial leakage and dysfunction increasing influx of proinflammatory and proatherogenic cellular and noncellular substances into the vessel wall, is proposed as one feature of this new concept. In addition, the role of bone marrow-derived endothelial progenitor cells is discussed as are the potential impact of impaired progenitor cell mobilization, release from the marrow, and function in acute and stable coronary artery disease. Finally, potential future therapies are proposed, focusing on interventions that may prevent or diminish the development of the microvascular and microcellular endothelial dysfunction.     

Linear and angular measurements of computer-generated models: are they accurate, valid, and reliable?

INTRODUCTION: Traditional advanced imaging modalities such as CT and MRI are limited in their ability to perform accurate linear distance and angular measurements regardless of anatomical orientation. The construction of 3D models has been used to perform anthropometric analyses as well as in the reconstruction of rapid prototypes. We hypothesized that such measurements would be precise to within 2 mm or 2 degrees of measurements performed with a coordinate measurement machine (CMM). We also hypothesized that there would be a high degree of interobserver reliability with these measurements. MATERIALS AND METHODS: Multiple aluminum screws were implanted in various positions in three foam pelvises which were subsequently scanned by CT and rendered as 3D models using a commercially available software package (Mimics). Linear and angular measurements were performed using a CMM machine, the software package, and a dial caliper or goniometer. The deviation of the measurements from the CMM data was compared using ANOVA. The interobserver reliability of both the manual and computer-generated measurements was calculated. RESULTS: The mean difference between the CMM distances and those measured manually and with the software was 2.12 +/- 1.20 mm and 1.57 +/- 1.05 mm, respectively. The mean difference between the CMM angular measurements and the angular measurements performed manually and with the software was 4.07 +/- 4.70 degrees and 1.62 +/- 1.32 degrees, respectively. In all cases, the manual measurements were significantly less accurate (p < 0.0001) and there was a high degree of interobserver reliability. CONCLUSIONS: Computer-generated measurements taken from three-dimensionally reconstructed models are more accurate than manual measurements and are within 2 mm and 2 degrees of measurements performed with a CMM. These measurements have high interobserver reliability.     

Improved outcomes using a systematic and evidence-based approach to the laparoscopic Roux-en-Y gastric bypass in a single academic institution

No standardized approach exists for laparoscopic Roux-en-Y gastric bypass (LRYGB). At a newly instituted bariatric surgery program, four experienced laparoscopic surgeons used the systematic and evidence-based approach consisting of multidisciplinary preoperative evaluation, screening, and education; standardized operative technique; inpatient clinical pathway; and close postoperative follow-up. The outcomes were subsequently analyzed to determine if this approach improved the morbidity and mortality. From January 2003 to June 2006, 835 consecutive LRYGBs were performed. The patient population was 85 per cent women with a mean body mass index (BMI) of 50.4 kg/m2 (range 33-96 kg/m2). The mean age was 44 (range 15-67). Sixty-two per cent of the patients had previous abdominal or pelvic operations. The conversion rate to open surgery was 0.2 per cent. The average length of hospital stay was 2.6 days (range 2-13 days). There were no anastomotic leaks or deaths. The 30-day readmission and re-operation rates were 3.2 per cent and 1.8 per cent, respectively. The incidence of anastomotic stricture, marginal ulcer, bleeding, pulmonary embolism, and internal hernia was 0.8 per cent, 3.5 per cent, 4.2 per cent, 0.1 per cent, and 0.4 per cent, respectively. A systematic and evidence-based approach to the LRYGB by experienced laparoscopic surgeons resulted in a lower incidence of complications when compared with the published results from other comparable institutions.     

Laparoscopic versus non-laparoscopic-assisted ventriculoperitoneal shunt placement in adults. A retrospective analysis

BACKGROUND: Ventriculoperitoneal shunts and distal shunt revisions bear a high risk of distal malfunction, especially in patients with previous abdominal pathologies as well as in obese patients. We performed laparoscopy-guided distal shunt placement or revision for patients with and without a positive abdominal history. We review the indications, techniques, complications, and long-term outcomes of these cases and compare the results to those of patients operated without laparoscopic guidance. METHODS: A total of 211 distal shunt procedures were performed in our institute between January 2001 and December 2005, 59 of which were laparoscopically guided, and 152 were not. Of the 211 procedures, 177 were placement of new shunt systems, and 34 were distal revisions. A total of 33 procedures were performed in 25 patients with a history of abdominal surgery or inflammatory bowel disease; 15 procedures were operated with laparoscopic guidance. RESULTS: The short-term complication and outcome rates were similar between the laparoscopy group and the other patients. Among the patients with new shunts, the long-term distal malfunction rate was lower in the laparoscopy group compared with the nonlaparoscopy group (4% vs 10.3%, respectively; P = .17). No patients in the laparoscopy group and 6 patients operated by other techniques had distal malfunction. There was 1 laparoscopy-related mortality and no morbidity. CONCLUSIONS: Laparoscopy is not routinely indicated in distal shunt placement or revision. However, a laparoscopy-guided procedure may lower the rate of distal malfunction in patients with previous abdominal surgeries.     

Combination of anti-CD4 with anti-LFA-1 and anti-CD154 monoclonal antibodies promotes long-term survival and function of neonatal porcine islet xenografts in spontaneously diabetic NOD mice

Type 1 diabetes mellitus (T1DM) is caused by the autoimmune destruction of pancreatic islet beta-cells, which are required for the production of insulin. Islet transplantation has been shown to be an effective treatment option for TIDM; however, the current shortage of human islet donors limits the application of this treatment to patients with brittle T1DM. Xenotransplantation of pig islets is a potential solution to the shortage of human donor islets provided xenograft rejection is prevented. We demonstrated that a short-term administration of a combination of anti-LFA-1 and anti-CD154 monoclonal antibodies (mAbs) was highly effective in preventing rejection of neonatal porcine islet (NPI) xenografts in non-autoimmune-prone B6 mice. However, the efficacy of this therapy in preventing rejection of NPI xenografts in autoimmune-prone nonobese diabetic (NOD) mice is not known. Given that the current application of islet transplantation is for the treatment of T1DM, we set out to determine whether a combination of anti-LFA-1 and anti-CD154 mAbs could promote long-term survival of NPI xenografts in NOD mice. Short-term administration of a combination of anti-LFA-1 and anti-CD154 mAbs, which we found highly effective in preventing rejection of NPI xenografts in B6 mice, failed to promote long-term survival of NPI xenografts in NOD mice. However, addition of anti-CD4 mAb to short-term treatment of a combination of anti-LFA-1 and anti-CD154 mAbs resulted in xenograft function in 9/12 animals and long-term graft (>100 days) survival in 2/12 mice. Immunohistochemical analysis of islet grafts from these mice identified numerous insulin-producing beta-cells. Moreover, the anti-porcine antibody as well as autoreactive antibody responses in these mice was reduced similar to those observed in naive nontransplanted mice. These data demonstrate that simultaneous targeting of LFA-1, CD154, and CD4 molecules can be effective in inducing long-term islet xenograft survival and function in autoimmune-prone NOD mice.     

Colonoscopic Perforation Management by Laparoendoscopy: An Algorithm

Background and Objectives:

The role of laparoscopy in the management of iatrogenic colonoscopic injuries has increased with surgeons becoming facile with minimally invasive methods. However, with a limited number of reported cases of successful laparoscopic repair, the exact role of this modality is still being defined. Drawing from previous literature and our own experiences, we have formulated a simple algorithm that has helped us treat colonoscopic perforations.

Methods:

A retrospective review was undertaken of patients treated for colonoscopic perforations since the algorithm''s introduction. For each patient, initial clinical assessment, management, and postoperative recovery were carefully documented. A Medline search was performed, incorporating the following search words: colonoscopy, perforation, and laparoscopy. Twenty-three articles involving 106 patients were identified and reviewed.

Results:

Between May 2009 and August 2012, 7 consecutive patients with colonoscopic perforations were managed by 2 surgeons using the algorithm. There were no complications and no deaths, with a mean length of stay of 4.43 days (range, 2–7 days). Of the 7 patients, 6 required surgery. A single patient was managed conservatively and later underwent an elective colon resection.

Conclusions:

Traditionally, laparotomy was the preferred method for treating colonoscopic perforations. Our initial experience reinforces previous views that laparoendoscopic surgery is a safe and effective alternative to traditional surgery for managing this complication. We have formulated a simple algorithm that we have found helpful for surgeons considering a laparoscopic approach to managing this condition.