The effect of skin expansion on acellular dermis in an experimental model

Objective: Although acellular dermis is widely used in prosthesis-based breast reconstruction, there is no study evaluating its expandability and histological, ultra-structural related changes. The purpose of this study is to determine whether acellular dermis could be expanded and whether the histological changes occurring in the skin with tissue expansion is different from normal when acellular dermis is used.

Methods: Twenty-two male Wistar rats were used in this study. In group 1 (n?=?6), a rectangular-shaped tissue expander with final volume of 35?ml was placed subcutaneously. In group 2 (n?=?6) tissue expander was placed submuscularly. In group 3 (n?=?6), a 4?×?5?cm, acellular dermis was inserted and sutured in place, tissue expander was placed underneath acellular dermis. Group 4 (n?=?4) was control, no procedure was done after creation of a pocket. After day 30, tissue expanders were inflated with 2?ml every 2 days with saline solution. On day 66, midvertical, midhorizontal surface expansion measurements were recorded. Samples were examined macroscopically. Biopsies were taken from mid-point of the expanded full-thickness flap. Histological evaluation, total skin thickness, epidermal thickness, and the amount of vascularisation were measured.

Results: There was no expansion noted on the acellular dermis; however, acellular dermis increased vascularity and decreased the thinning of the overlying skin and thickening of the epidermis when compared to other groups.

Conclusion: Acellular dermis use can be beneficial in implant-based breast reconstruction in terms of morbidity and its tissue support.     

Evaluation of treatment response of chemoembolization in hepatocellular carcinoma with diffusion-weighted imaging on 3.0-T MR imaging

PurposeTo assess the treatment response of hepatocellular carcinoma (HCC) after transarterial chemoembolization with diffusion-weighted imaging and dynamic contrast-enhanced magnetic resonance (MR) imaging with a 3-T system.Materials and MethodsBetween February 2010 and November 2010, 74 patients were treated with chemoembolization in our interventional radiology unit. Twenty-two patients (29%) who had liver MR imaging including diffusion and dynamic contrast-enhanced MR imaging on a 3-T system before and after transarterial chemoembolization were evaluated retrospectively. Tumor size, arterial enhancement, venous washout, and apparent diffusion coefficient (ADC) values of lesions, peritumoral parenchyma, normal liver parenchyma, and spleen were recorded before and after treatment. The significance of differences between ADC values of responding and nonresponding lesions was calculated.ResultsThe study included 77 HCC lesions (mean diameter, 31.4 mm) in 20 patients. There was no significant reduction in mean tumor diameter after treatment. Reduction in tumor enhancement in the arterial phase was statistically significant (P = .01). Tumor ADC value increased from 1.10 × 10^?3 mm²/s to 1.27 × 10^?3 mm²/s after treatment (P < .01), whereas the ADC values for liver and spleen remained unchanged. ADC values from cellular parts of the tumor and necrotic areas also increased after treatment. However, pretreatment ADC values were not reliable to identify responding lesions according to the results of receiver operating characteristic analysis.ConclusionsAfter transarterial chemoembolization, responding HCC lesions exhibited decreases in arterial enhancement and increases in ADC values in cellular and necrotic areas. Pretreatment ADC values were not predictive of response to chemoembolization.     

Dosimetric comparison of organs at risk in 5 different radiotherapy plans in patients with preoperatively irradiated rectal cancer

Background:Intensity-modulated radiotherapy (IMRT) is a widely used irradiation technique in rectal cancer patients. We aimed to compare 4 different IMRT plans with 3-dimensional conformal radiotherapy (3D-CRT) considering organs at risk (OARs) in patients with rectal carcinoma.Methods:This retrospective study included 27 rectal cancer patients who were irradiated preoperatively between January 2016 and December 2018. Five different plans (4-field 3D-CRT in 2 phases, 7-field IMRT in 2 phases, 9-field IMRT in 2 phases, 7-field simultaneous integrated boost [SIB] IMRT, and 9-field SIB IMRT) were generated for each patient. Comparison of 5 different plans according to bladder and bilateral femoral head mean doses, bladder V40, bilateral femoral head V40, and small bowel V35 values were evaluated.Results:Most of the OAR parameters significantly favored IMRT plans compared to the 3D-CRT plan. The largest difference was observed in bladder V40 values (reduction of V40 value up to 51.2% reduction) in favor of IMRT. In addition, SIB plans showed significantly better reduction in OARs than phase plans except for small bowel V35 values.Conclusions:IMRT plans reduced almost all the OARs doses compared with the 3D-CRT plan in rectal cancer patients. Furthermore, SIB plans demonstrated lower OAR doses than the phase plans. IMRT techniques, especially SIB plans, reduce OAR doses and provide safer doses for the treatment of rectal carcinoma.     

Enhanced coagulation activation by in vitro lipopolysaccharide challenge in patients with ventricular fibrillation complicating acute myocardial infarction

BACKGROUND: Indicators of coagulation and inflammation are elevated in patients with coronary heart disease. A role of coagulation activation in ventricular fibrillation during acute myocardial infarction has not been described. METHODS AND RESULTS: Whole blood samples of 21 patients with a history of acute myocardial infarction complicated by ventricular fibrillation and whole blood samples of 18 patients without ventricular fibrillation were incubated with lipopolysaccharide (LPS). In both groups, the in vitro blood coagulation time was measured with the ReoRox, a viscometric whole blood coagulometer. CD62P expression on platelets, tissue-factor binding on monocytes, and platelet-monocyte aggregates were measured with flow cytometry. Without LPS, no difference in the coagulation times were observed in both patient groups. After incubation with LPS, patients with a history of ventricular fibrillation showed a significantly decreased coagulation time compared to patients without ventricular fibrillation. The decrease of coagulation time after incubation with LPS also differed significantly in both groups. Expression of CD62P on platelets was significantly higher in patients with a history of ventricular fibrillation after incubation with LPS. Although in each patient group incubation with LPS induced a significantly increased amount of tissue factor on monocytes and a significantly increased the number of platelet-monocyte aggregates, the two groups did not differ significantly concerning tissue factor binding on monocytes and the amount of platelet-monocyte aggregates. CONCLUSIONS: After in vitro LPS challenge, patients with a history of ventricular fibrillation during myocardial infarction show an enhanced coagulation activation, which may partly be due to an enhanced platelet activation.     

Pancreatic Castleman’s Tumour: an Unusual Case

We present an uncommon case of hyaline vascular type Castleman’s disease mimicking a pancreatic tumour. A 56-year-old woman with constitutional symptoms was investigated. Pre-operative interventions failed to produce a definitive diagnosis. Surgical excision was performed and the tumour was diagnosed to be the hyaline vascular type of Castleman’s disease histopathologically. Pancreatic Castleman’s disease should remain a consideration in the differential diagnosis of a pancreatic mass.     

Confirmation of Calcium Phosphate Cement Biodegradation after Jawbone Augmentation around Dental Implants Using Three-Dimensional Visualization and Segmentation Software

The use of autologous bone graft for oral rehabilitation of bone atrophy is considered the gold standard. However, the available grafts do not allow a fast loading of dental implants, as they require a long healing time before full functionality. Innovative bioactive materials provide an easy-to-use solution to this problem. The current study shows the feasibility of calcium phosphate cement paste (Paste-CPC) in the sinus. Long implants were placed simultaneously with the cement paste, and provisional prosthetics were also mounted in the same sessions. Final prosthetics and the full loading took place within the same week. Furthermore, the study shows for the first time the possibility to monitor not only healing progression using Cone Beam Computer tomography (CBCT) but also material retention, over two years, on a case study example. The segmented images showed a 30% reduction of the cement size and an increased mineralized tissue in the sinus. Mechanical testing was performed qualitatively using reverse torque after insertion and cement solidification to indicate clinical feasibility. Both functional and esthetic satisfaction remain unchanged after one year. This flowable paste encourages the augmentation procedure with less invasive measure through socket of removed implants. However, this limitation can be addressed in future studies.     

Cutaneous manifestations of COVID‐19: A review of the published literature

COVID‐19 is a highly contagious respiratory tract infection caused by severe acute respiratory syndrome coronavirus 2. COVID‐19 outbreak, which caused thousands of deaths, has been declared a pandemic by the World Health Organization in March 2020. The infection has been reported to demonstrate different types of cutaneous manifestations including urticarial, maculopapular, papulovesicular, purpuric, livedoid, and thrombotic‐ischemic lesions. Given the high mortality rate of the infection, timely and accurate identification of relevant cutaneous manifestations may play a key role in the early diagnosis and management. In this study, we provide a review with a focus on the reported cutaneous manifestations of COVID‐19.