Accuracy of magnetic resonance imaging for preoperative detection of portal vein thrombosis in liver transplant candidates.

The detection of main portal vein thrombosis (PVT) on preoperative imaging of liver transplant candidates has important technical implications for the transplantation procedure. Data are scarce regarding the accuracy of magnetic resonance imaging (MRI) at detecting PVT. The aim of our study was to compare preoperative findings of the portal vein on MRI to operative findings at liver transplantation. Abdominal MRI and clinical records of 172 consecutive patients who received liver transplants between January 1999 and September 2004 were reviewed. Two radiologists independently evaluated the last abdominal magnetic resonance examinations obtained before liver transplantation, blinded to the original reading, operative findings, and clinical data. Findings on MRI were compared with intraoperative findings at transplantation. Main PVT was detected in 12 patients, in whom 8 were found to have thrombus at surgery, with 6 requiring a jump graft or thrombectomy. Sensitivity and specificity of MRI for detecting main PVT were 100% and 98%, respectively. The cause of discordance between findings on MRI and at transplantation in 2 cases was a diminutive caliber of the main portal vein that was interpreted as recanalized chronic thrombosis on MRI. In conclusion, in our study group MRI detected PVT in all liver transplant recipients requiring jump grafts at transplantation. The major reason for a false-positive MRI was a diminutive but patent portal vein.     

Gastrogastric fistula: a possible complication of Roux-en-Y gastric bypass.

BACKGROUND: Gastrogastric fistula is a communication between the proximal gastric pouch and the distal gastric remnant, rarely described in the realm of bariatric procedures. The aim of this study was to review the existing literature about this topic and to demonstrate its laparoscopic treatment. METHODS: An extensive literature review found several articles reporting this complication. However, no citation was found describing the steps of the laparoscopic management of this situation. RESULTS: Gastrogastric fistula occurs in up to 6% of Roux-en-Y gastric bypasses. Two theories exist for fistula formation: (1) it is a technical complication derived from the incomplete division of the stomach during the creation of the pouch, and (2) it occurs after a staple-line failure, developing a leak with an abscess, which then drains into the distal stomach forming the fistula. Early symptoms include fever, tachycardia, and abdominal pain. Failure in weight loss is a late clinical sign observed in these patients. Diagnosis is based on radiologic study, upper endoscopy and computed tomography. When identified in the acute postoperative course, laparoscopic treatment is easy. Chronic fistulas are difficult to manage, and the laparoscopic approach is an alternative to open surgery. CONCLUSIONS: Gastrogastric fistula is a possible complication of Roux-en-Y gastric bypass and its laparoscopic treatment is feasible.     

Analysis of KIR2D receptors on peripheral blood lymphocytes from liver graft recipients

KIR2D receptors are killer cell immunoglobulin-like receptors (KIRs) specific for HLA-C epitopes, that are expressed on NK cells as well as on minor peripheral blood T-cell subsets, and are able to control NK and T cells activity. The present work explores NK, and particularly CD8(+) T cells expressing KIR2D2L1/S1 (CD158a) or KIR2D2L2/3/S2 (CD158b) receptors in liver graft alloresponse. Flow cytometry was used to analyse peripheral blood mononuclear cells stained with anti-CD158a and anti-CD158b antibodies from 110 liver recipients and 46 healthy controls, previous to and along the first month after transplantation. Pre-transplantation data shows that both CD158a and CD158b molecules can be detected on NK and T cells from all patients and controls, but both KIR2D(+)NK cells are significantly under-represented in patients respect to controls (P<0.001), and CD3(+)CD8(+)CD158a(+) cells decreased particularly in patients suffering from acute rejection (4.03+/-1.33 cells/microL) compared with controls (7.8+/-2.4 cells/microL). Following transplantation, KIR2D(+)CD8(+) T-cell repertoires increased through the first month, mainly in recipients with a good graft acceptance. In summary, monitoring of KIR2D(+)CD8(+) T cells, particularly KIR2DL1/S1(+)CD8(+) T cells at pre-transplant, and both KIR2DL1/S1(+) and KIR2DL2/3/S2(+) T-cell subsets at early post-transplant period, could offer useful information for clinical follow-up of liver grafts.     

Transmediastinal gunshot wounds in a mature trauma centre: Changing perspectives

Background

Transmediastinal gunshot wounds are associated with a high mortality and frequently require operative intervention. The purpose of this study was to identify the diagnostic and therapeutic challenges of these injuries in a mature trauma system with decreasing prehospital time intervals.

Methods

Patients admitted to a large urban Level 1 trauma centre between 1/2006 and 12/2010 sustaining a firearm injury to the torso were identified. Transmediastinal gunshot wounds were defined as missile tracts traversing the mediastinum identified on CT images, operative notes or autopsy reports.

Results

Overall, 133 patients met study criteria. A total of 116 patients (87.2%) were haemodynamically unstable or had no vital signs on arrival to the Emergency Department. Ninety-seven (83.6%) of these patients required a resuscitative thoracotomy resulting in 8 survivors (6.0%). There were 17 haemodynamically stable patients (12.8%) identified, 14 of whom underwent CT scan evaluation. Six patients subsequently required operative intervention. Only 11 patients (8.3%) in the study population were successfully managed nonoperatively. The overall mortality was 78.9%, and for those who reached the hospital with vital signs, the mortality was 24.3%.

Conclusions

Transmediastinal gunshot wounds encountered in a mature trauma centre are highly lethal injuries requiring resuscitative thoracotomy in most instances. Changing perspectives in these injuries may reflect the effects of an evolving prehospital care.     

Traumatic brain injury biomarkers in pediatric patients: a systematic review

Neurosurgical Review - Traumatic brain injury (TBI) is the main cause of pediatric trauma death and disability worldwide. Recent studies have sought to identify biomarkers of TBI for the purpose of...     

How to Manage Cartilage Injuries?

Although small cartilage injuries are commonly found in knee arthroscopy procedures, significant chondral and osteochondral injuries are relatively infrequent. Incidence of cartilage injury rises when considering traumatic origin, especially when approaching significant ligamentous or meniscal pathology. Options for restoration span the gamut from benign neglect to open procedures that restore both cartilage and subchondral bone. The best choice of procedure largely depends on lesion size, depth, and location. Smaller lesions isolated to cartilage <2 cm² can be treated with marrow stimulation techniques such as microfracture with or without biologic options (bone marrow aspirate concentrate or platelet-rich plasma with or without cartilage precursors or scaffolds). Microfracture alone in larger lesions has been reported to be less durable and it is therefore not recommended for larger lesions. Smaller lesions <2 cm² that include a subchondral injury can be treated with osteochondral autograft implantation, in which a core of cartilage and bone is transferred from a relative non-weightbearing surface to the lesion.Larger osteochondral lesions >2 cm² are better treated with osteochondral allograft transplantation, where osteochondral cores from a size-matched, fresh cadaver are matched to the patient's lesion. This option may require multiple cores to be placed in a “snowman” pattern; however, recent literature demonstrated that a single plug might produce better outcomes. Alternatively, for large chondral-only lesions, a resurfacing procedure may be chosen that may include biologic options. Autologous chondrocyte implantation (ACI), currently in its third iteration (matrix ACI [MACI]), is an excellent choice with good long-term durability. In addition, MACI may be used for chondral lesions in the patellofemoral joint where matching the native joint topology may be more difficult. If the patient has an underlying bone marrow lesion but an intact cartilage cap that appears healthy on arthroscopic examination, one may consider a core decompression and injection with biologics such as BMAC and bony scaffold with fibrin glue (also known as bioplasty).It is also critical that the surgeon address any concomitant knee pathology that would compromise cartilage restoration. This includes addressing malalignment with distal femoral, proximal tibial, or tibial tubercle osteotomy, significant meniscal deficiency with meniscal transplant, and any instability from lack of cruciate or collateral ligaments with ligament reconstruction.     

Outcomes of Superficial and Deep Irrigation and Debridement in Total Hip and Knee Arthroplasty

BackgroundFollowing total knee arthroplasty and total hip arthroplasty, wound-related problems and deep periprosthetic joint infection may present in a similar fashion. Irrigation and debridement (I&D) has a great role in management of patients with early infection. The question that often arises is how to tell the difference between superficial and deep infection. This study evaluated the role and outcomes of both superficial and deep I&D in patients with wound-related issues and/or suspected periprosthetic joint infection.MethodsA retrospective study was conducted evaluating patients who underwent I&D within 28 days of total joint arthroplasty. A total of 176 cases with a minimum of 1-year follow-up were identified, and clinical records were reviewed in detail. Reoperations included superficial (fascia not opened) or deep (fascia opened) I&D. Failure was defined as the need for further surgical intervention within 1 year of initial I&D.ResultsThe overall success for superficial I&D was 84.28% vs 68.86% for deep I&D. The success of both deep and superficial I&D was higher if the I&D was performed closer to the index surgery. Superficial I&D in patients with a positive joint aspiration or evidence of intraoperative purulence or those in whom had no subcutaneous fluid had higher failure rates.ConclusionSuperficial I&D is a viable option in patients with wound-related issues as long as joint aspiration is performed to rule out infection involving the prosthesis. If there are findings of no fluid or purulence, fascia may need to be opened and the deeper tissues explored.     

Emerging Aspects of the Body Composition,Bone Marrow Adipose Tissue and Skeletal Phenotypes in Type 1 Diabetes Mellitus

Anthropomorphic measures among type 1 diabetic patients are changing as the obesity epidemic continues. Excess fat mass may impact bone density and ultimately fracture risk. We studied the interaction between bone and adipose tissue in type 1 diabetes subjects submitted to two different clinical managements: (I) conventional insulin therapy or (II) autologous nonmyeloablative hematopoietic stem-cell transplantation (AHST). The study comprised 3 groups matched by age, gender, height and weight: control (C = 24), type 1 diabetes (T1D = 23) and type 1 diabetes treated with AHST (T1D-AHST = 9). Bone mineral density (BMD) and trabecular bone score (TBS) were assessed by dual X-ray absorptiometry (DXA). ¹H Magnetic resonance spectroscopy was used to assess bone marrow adipose tissue (BMAT) in the L3 vertebra, and abdominal magnetic resonance imaging was used to assess intrahepatic lipids (IHL), visceral (VAT) and subcutaneous adipose tissue (SAT). Individuals conventionally treated for T1D were more likely to be overweight (C = 23.8 ± 3.7; T1D = 25.3 ± 3.4; T1D-AHST = 22.5 ± 2.2 Kg/m²; p > 0.05), but there was no excessive lipid accumulation in VAT or liver. Areal BMD of the three groups were similar at all sites; lumbar spine TBS (L3) was lower in type 1 diabetes (p < 0.05). Neither SAT nor VAT had any association with bone parameters. Bone marrow adipose tissue (BMAT) lipid profiles were similar among groups. BMAT saturated lipids were associated with cholesterol, whereas unsaturated lipids had an association with IGF1. Overweight and normal weight subjects with type 1 diabetes have normal areal bone density, but lower trabecular bone scores. Adipose distribution is normal and BMAT volume is similar to controls, irrespective of clinical treatment.     

Infrared photobiomodulation (PBM) therapy improves glucose metabolism and intracellular insulin pathway in adipose tissue of high-fat fed mice

Obesity represents a continuously growing global epidemic and is associated with the development of type 2 diabetes mellitus. The etiology of type 2 diabetes is related to the resistance of insulin-sensitive tissues to its action leading to impaired blood glucose regulation. Photobiomodulation (PBM) therapy might be a non-pharmacological, non-invasive strategy to improve insulin resistance. It has been reported that PBM therapy in combination with physical exercise reduces insulin resistance. Therefore, the aim of this study was to investigate the effects of PBM therapy on insulin resistance in obese mice. Male Swiss albino mice received low-fat control diet (n?=?16, LFC) or high-fat diet (n?=?18, HFD) for 12 weeks. From 9th to 12th week, the mice received PBM therapy (LASER) or Sham (light off) treatment and were allocated into four groups: LFC Sham (n?=?8), LFC PBM (n?=?8), HFD Sham (n?=?9), and HFD PBM (n?=?9). The PBM therapy was applied in five locations: to the left and right quadriceps muscle, upper limbs and center of the abdomen, during 40 s at each point, once a day, 5 days a week, for 4 weeks (780 nm, 250 mW/cm², 10 J/cm², 0.4 J per site; 2 J total dose per day). Insulin signaling pathway was evaluated in the epididymal adipose tissue. PBM therapy improved glucose tolerance and phosphorylation of Akt (Ser473) and reversed the HFD-induced reduction of GLUT4 content and phosphorylation of AS160 (Ser588). Also, PBM therapy reversed the increased area of epididymal and mesenteric adipocytes. The results showed that chronic PBM therapy improved parameters related to obesity and insulin resistance in HFD-induced obesity in mice.