Prospective, multicenter study of antimicrobial-coated, noncrosslinked, acellular porcine dermal matrix (XenMatrix™ AB Surgical Graft) for hernia repair in all centers for disease control and prevention wound classes: 24-month follow-up cohort.

Prospective, multicenter, single-arm study of antimicrobial-coated, noncrosslinked, acellular porcine dermal matrix (AC-PDM) in a cohort involving all centers for disease control and prevention wound classes in ventral/incisional midline hernia repair (VIHR). Materials and methods: Seventy-five patients (mean age 58.6±12.7 years; BMI 31.3±4.9 kg/m2) underwent ventral/incisional midline hernia repair with AC-PDM. Surgical site occurrence (SSO) was assessed in the first 45 days post-implantation. Length of stay, return to work, hernia recurrence, reoperation, quality of life, and SSO were assessed at 1, 3, 6, 12, 18, and 24 months. Results: 14.7% of patients experienced SSO requiring intervention within 45 days post-implantation, and 20.0% thereafter (>45 d post-implantation). Recurrence (5.8%), definitely device-related adverse events (4.0%), and reoperation (10.7%) were low at 24 months; all quality-of-life indicators were significantly improved compared to baseline. Conclusion: AC-PDM exhibited favourable results, including infrequent hernia recurrence and definitely device-related adverse events, with reoperation and SSO comparable to other studies, and significantly improved quality of life.

Dehydrated Human Amnion/Chorion Grafts May Accelerate the Healing of Ulcers on Free Flaps in Patients With Venous Insufficiency and/or Lymphedema.

OBJECTIVE: Ulceration of free flaps in patients with venous insufficiency and/or lymphedema is an uncommon but challenging problem. We hypothesized that dehydrated human amnion/chorion membrane (Epifix) grafts would accelerate healing of these challenging ulcers. METHODS: Retrospective analysis of prospectively acquired data identified 8 lower extremity free flaps with ulcerations in the context of venous insufficiency and/or lymphedema. The first 4 were flaps that had been treated with conservative wound care to healing. The second group was treated conservatively initially but then converted to treatment with dehydrated human amnion/chorion membrane grafts. The primary endpoint was time to healing. RESULTS: Comparison of Kaplan-Meier survival curves revealed a significant difference between the conservatively and dehydrated human amnion/chorion membrane-treated flap ulcers, favoring graft treatment (P = .0361). In those ulcers that healed, the average time to healing was 87 days for the conservative treatment group and 33 days for the dehydrated human amnion/chorion membrane treatment group (with an average of 1.7 grafts per ulcer). CONCLUSIONS: Dehydrated human amnion/chorion membrane may accelerate healing of ulcers on lower extremity free flaps in patient with lymphedema and/or venous disease in the treated leg.

Cranial and Cervical Muscular Weakness in Mitochondrial Myopathy Is Associated With Resolution of Migraine Headaches: Further Evidence That Muscular Compression of Cranial and Peripheral Nerves Is a Cause of Headache in a Subset of Patients With Migraine.

OBJECTIVE: A significant subset of patients with migraine headaches has pain relief after neuroplasty/muscular decompression of select cranial and cervical nerves. In the majority of cases, compression occurs secondary to compression of the nerves by adjacent muscles. Previous studies have shown that both surgical decompression and chemical denervation (eg, botulinum toxin) provide relief of migraine headaches; however, controversy remains. If some migraine headaches are caused by muscular compression, then paresis of the compressing muscles by underlying myopathic/metabolic disease should result in migraine relief in some patients. METHODS: We report a case of mitochondrial myopathy causing weakness primarily of the muscles of facial expression and the neck in the context of chronic migraine headaches (>20-year history). Muscle biopsy was obtained to confirm the myopathic diagnosis. RESULTS: There was complete resolution of the patient's migraine headaches that occurred simultaneously with the onset of symptomatic paresis of the muscles of facial expression and the neck. The relief has persisted for more than 10 months. Neurologic evaluation and muscle biopsy confirmed a diagnosis of mitochondrial myopathy. CONCLUSIONS: Pathologic paresis/paralysis of facial and/or cervical muscles can result in persistent resolution of migraine headache pain, giving further evidence to the concept that peripheral and/or cranial nerve compression causes migraine headache pain in a subset of patients with a diagnosis of migraine.

Reoperative selective sentinel lymphadenectomy combined with lymphoscintigraphy is technically feasible for cutaneous tumors of the upper extremity after radical dissection of regional lymph node basins for breast cancer.

OBJECTIVE: The rising incidence of melanoma and the high prevalence of breast cancer have generated a new scientific problem-how do the regional lymph node basins function after radical lymphadenectomy and are lymphatic drainage patterns altered after radical lymphadenectomy? Furthermore, after radical lymphadenectomy, selective sentinel lymphadenectomy is still a technically feasible and valid staging tool in the upper extremity? Thus, our study asks if selective sentinel lymph node dissection is technically feasible after radical lymph node dissection of the regional draining basin of the upper extremity (axilla). METHODS: Retrospective review of a prospectively maintained database of patients was reviewed to identify patients who had lymphoscintigraphy and sentinel lymph node biopsy of the upper extremity after a radical axillary node dissection procedure. Imaging and pathology results were analyzed. RESULTS: Seven patients fulfilling the inclusion criteria were identified. The patients all had either melanoma or invasive squamous cell carcinoma, and sentinel lymph nodes were identified in 6 out of 7 patients. One patient had metastases to 2 sentinel lymph nodes. Alternative drainage pathways were identified in 29% of patients, and 14% of patients had no identifiable drainage basin on lymphoscintigraphy. CONCLUSIONS: Sentinel lymph node dissection is technically feasible after previous axillary dissection. Lymphoscintigraphy is an important perioperative tool as lymphatic drainage may be altered or not observed as evidenced in 43% of the studied patients. However, when lymphatic drainage is detected by lymphoscintigraphy, pathologically significant sentinel lymph nodes are surgically identifiable.

Crystal structures of the Tie2 receptor ectodomain and the angiopoietin-2-Tie2 complex.

The Tie receptor tyrosine kinases and their angiopoietin (Ang) ligands play central roles in developmental and tumor-induced angiogenesis. Here we present the crystal structures of the Tie2 ligand-binding region alone and in complex with Ang2. In contrast to prediction, Tie2 contains not two but three immunoglobulin (Ig) domains, which fold together with the three epidermal growth factor domains into a compact, arrowhead-shaped structure. Ang2 binds at the tip of the arrowhead utilizing a lock-and-key mode of ligand recognition-unique for a receptor kinase-where two complementary surfaces interact with each other with no domain rearrangements and little conformational change in either molecule. Ang2-Tie2 recognition is similar to antibody-protein antigen recognition, including the location of the ligand-binding site within the Ig fold. Analysis of the structures and structure-based mutagenesis provide insight into the mechanism of receptor activation and support the hypothesis that all angiopoietins interact with Tie2 in a structurally similar manner.

Routine imaging of asymptomatic melanoma patients with metastasis to sentinel lymph nodes rarely identifies systemic disease.

HYPOTHESIS: The diagnostic yield of chest radiography; computed tomography (CT) of the chest, abdomen, and pelvis; and CT or magnetic resonance imaging of the brain in the initial evaluation of melanoma with metastasis to sentinel lymph nodes may not identify systemic disease. DESIGN: Retrospective analysis. SETTING: Tertiary care referral center. PATIENTS: Of 1183 patients identified from a database of individuals who underwent selective sentinel lymphadenectomy for primary melanoma (Breslow thickness, 0.2-30 mm), we studied 185 with at least 1 sentinel lymph node positive for metastatic melanoma (Breslow thickness, 0.8-14.5 mm). INTERVENTIONS: Chest radiography; CT of the chest, abdomen, and pelvis; and CT or magnetic resonance imaging of the brain after selective sentinel lymphadenectomy with positive sentinel lymph nodes. The medical records of the 185 patients were systematically reviewed by 4 physician reviewers, and data were extracted primarily from pathology and radiology reports. When medical records were unavailable, information was taken from formal clinic and inpatient progress notes. MAIN OUTCOME MEASURE: Diagnostic yield of imaging studies. RESULTS: The results of 0.5% of the imaging studies were positive for metastatic disease, 86% were negative, and 14% were indeterminate. Indeterminate results were confirmed to be negative by additional studies ranging from repeated imaging to invasive procedures, including thoracotomy and brain biopsy. The yields are as follows: chest radiography, 0%; chest CT, 0.7%; abdominal and pelvic CT, 0.7%; brain CT, 0%; and brain magnetic resonance imaging, 0%. Only 1 patient (0.5%) had detectable metastatic disease, and he had symptoms of systemic disease at the time of imaging. CONCLUSIONS: Computed tomography of the chest, abdomen and pelvis, and brain rarely reveals systemic metastasis at the time of selective sentinel lymphadenectomy. Routine imaging of asymptomatic patients at the time of selective sentinel lymphadenectomy is not indicated.