Areas Of Coagulative Necrosis Research Articles

Bronchopulmonary Aspergillosis Associated with Acute Myocardial Infarction in Dog

Background: Fungi of the genus Aspergillus are ubiquitous microorganisms of opportunistic character, of which animals and humans are continually exposed. Are described three main forms of aspergillosis in dogs: nasal, disseminated and bronchopulmonary. This form which is restricted to the lung parenchyma is considered rare in dogs. The aim of this paper is to report a case of pulmonary aspergillosis associated to acute myocardial infarction in a dog, focusing on epidemiological, clinical, pathological and immunohistochemical characteristics. Case: A male dog, 4-year-old, Pinscher, clinically presented dyspnea, anorexia, vomiting, concentrated urine and dark and mollifed faeces. On physical examination, there were congested oral and conjunctival mucosas, dehydration and petechiae in the outer ear. The animal died fve days after the clinical attendance and was sent for necropsy. The macroscopic lesions were restricted to the lung, heart and liver. There were multifocal areas of consolidation in the lung parenchyma and yellowish content in the trachea and bronchi lumen. The heart was rounded and with pale areas in the myocardium. Liver was discreet accentuation of the lobular pattern. Histologically the lesion was characterized by pyogranulomatous and necrotizing bronchopneumonia, multifocal to coalescing, moderate, associated with myriads of intralesional hyphae consistente with Aspergillus spp., associated with acute myocardial infarction. The hyphae weakly stained basophilic by hematoxylin and eosin were strongly impregnated by Grocott’s methenamine silver nitrate and showed strong immunolabelling of the cytoplasm, which were evidenced in brown. There were areas of acute myocardial infarction and hepatocellular degeneration and congestion in the liver, although fungal hyphae were not observed in these tissues. Discussion: The diagnosis of pulmonary aspergillosis was established based on the morphological and tinctorial characteristics of the agent and confrmed by immunohistochemistry. In this case, is not included in the clinical history any conditions that could promote immunosuppression, neither were observed morphological changes in the pathological examination which suggested other intercurrent diseases. It is likely that the dog has been exposed to the inhalation of large amounts of conidia for a long period of time, condition that favors the occurrence of the disease, even in immunocompetent animals. Probably were not evidenced severe respiratory clinical signs, that characterize the pulmonary impairment, due to the shortcourse of the disease. The pyogranulomatous and necrotizing inflammatory reaction is typical of fungal infection and was restricted to the lung parenchyma. The areas of coagulation necrosis observed in the myocardium are probably secondary to vascular injury caused by the fungi, with subsequent thromboembolism, ischemia and infarction. In Brazil, there are few reports of aspergillosis in dogs, have been reported the nasal and systemic forms. In the world literature, there are few reports about this bronchopulmonary form of the disease. Although uncommon, pulmonary aspergillosis should be considered in the differential diagnosis of diseases that affect the lower respiratory tract of dogs, as well as it’s systemic complications resulting from angioinvasive characteristic of the fungus, which in this case was determinant to the death of the animal. Keywords: Aspergillus, fungal disease, respiratory tract

Feasibility of a Low-Power Radiofrequency Ablation Protocol to Delay Steam Popping

PurposeSteam popping frequently occurs during conventional high-power radiofrequency (RF) ablation, increasing the risk of tumor spread. The aim of this study was to evaluate the effect of a low-power RF ablation protocol on the intensity and timing of steam popping in ex vivo bovine liver. Materials and MethodsHigh-power (maximum 200 W; group 1) and low-power (maximum 70 W; group 2) RF ablation protocols were established. In the first phase, RF ablation was conducted for 12 min. Ablation volume, intensity, and timing of maximal popping sounds and total energy generated for RF ablation were compared between groups 1 and 2. In the second phase, RF ablation was conducted until maximal popping occurred, and ablation zones on histologic specimens were compared. ResultsRelative to group 1, maximal popping occurred at significantly delayed timing in group 2 (50 s ± 11 vs 397 s ± 117; P < .001), but without a difference in intensity (ratios vs reference sound of 0.70 ± 0.18 vs 0.83 ± 0.26; P = .138). The ablation volume after 12 min of RF ablation did not differ between groups 1 and 2 (18.46 cm3 ± 1.35 vs 15.78 cm3 ± 0.64; P = .086). However, in the histologic specimens obtained when maximal popping occurred, the area of complete coagulative necrosis was significantly larger in group 2 (P < .05). ConclusionsLow-power RF ablation delays steam popping while providing comparable therapeutic effects to high-power RF ablation. Delaying maximal popping may prevent tumor cell dispersion because maximal popping occurs after an adequate ablation zone has been achieved.

AN OUTBREAK OF AVIAN PASTEURELLOSIS IN A TURKEY FARM

Avian Pasteurellosis is a contagious disease of domestic and wild birds caused by Pasteurellamutocida. A turkey farm with a flock size of 500 recorded an acute death of about 102 turkeys with the history of clinical symptoms such as respiratory distress, anorexia, mucoid discharge from mouth and the nostrils, diarrhea were presented to the Department of Veterinary Pathology, Veterinary College. On thorough postmortem examination, a salient finding of petechial haemorrhages with pinpoint necrotic spots though out the liver parenchyma was observed along with pneumonic changes in lungs and vascular changes in trachea, spleen and intestines. On histopathological examination, liver revealed multifocal areas of coagulative necrosis and haemorrhages. Heart showed separation, fragmentation and degeneration of fibers with extensive inter-muscular haemorrhages. Lungs were congested with haemorrhages and pneumonic changes. Based on history, gross &amp; histopathological lesions and impression smear examination after staining with geimsa and methylene blue, the case was diagnosed as Avian Pasteurellosis.

Necrotic Enteritis in Chickens Associated with Clostridium sordellii.

Three outbreaks of necrotic enteritis-like disease associated with Clostridium sordelii were diagnosed in commercial broiler chicken flocks with 18,000 to 31,000 birds between 18 and 26 days old. Clinical signs in the affected flocks included high mortality up to 2% a day, depression, and diarrhea. The main gross changes included segmental dilation of the small intestine with watery contents, gas, mucoid exudate, and roughened and uneven mucosa, occasionally covered with a pseudomembrane. Microscopic lesions in the small intestine were characterized by extensive areas of coagulative necrosis of the villi, fibrinous exudate in the lumen, and high numbers of large, Gram-positive rods, occasionally containing subterminal spores, seen in the necrotic tissue and lumen. These rods were identified as C. sordellii by immunohistochemistry. Clostridium sordellii was isolated in an almost pure culture from the intestine of affected birds. A retrospective study of commercial broiler chicken and turkey submissions to the California Animal Health and Food Safety Laboratory System revealed that C. sordellii had been isolated from intestinal lesions in outbreaks of necrotic enteritis-like disease in 8 of 39 cases, 5 times together with Clostridium perfringens and 3 times alone. The latter three cases are reported here.

Pancreatico-Gastric Anastomosis with and without Sutures – Experimental Swine Model

Abstract Objectives. The aim of our study is to identify a surgical technical that has the lowest rate of pancreatic fistulas in pancreatico-gastric anastomosis following duodenopancreatectomies. We studied pancreatico-gastric anastomosis performed with stitches compared to the ones performed without stitches. Methods. Our experimental model is based on ten piglets, which were divided into 2 groups. In the first group (n=5) the pancreatico-gastric anastomosis was done using double purse-string threads one passed through the gastric seromuscular layer and one through the gastric mucosa. In the second group (n=5) the pancreatico-gastric anastomosis was performed using sutures through the stomach and pancreas. Results. Postoperative amylasemia was higher in the second group. In the first group no pancreatico-gastric fistulas were observed, whereas pancreatic necrosis was observed only at a superficial level of the pancreatic stump. In the second group, two cases had developed fistulas, both bordered by large areas of coagulation necrosis accompanied by pancreatic duct hyperplasia. Duration of the anastomosis was shorter for the first group. Conclusions. In conclusion, the pancreatico-gastric anastomosis performed using two purse-string suture is a feasible, safe and fast process.

Intravoxel Incoherent Motion Diffusion Weighted MR Imaging for Monitoring the Instantly Therapeutic Efficacy of Radiofrequency Ablation in Rabbit VX2 Tumors without Evident Links between Conventional Perfusion Weighted Images.

ObjectiveTo investigate the intravoxel incoherent motion diffusion weighted imaging (IVIM-DWI) as a potential valuable marker to monitor the therapy responses of VX2 to radiofrequency ablation (RF Ablation).MethodsThe institutional animal care and use committee approved this study. In 10 VX2 tumor–bearing rabbits, IVIM-DWI examinations were performed with a 3.0T imaging unit by using 16 b values from 0 to 800 sec/mm2. The true diffusion coefficient (D), pseudodiffusion coefficient (D*) and perfusion fraction (f) of tumors were compared between before and instantly after RF Ablation treatment. The differences of D, D* and f and conventional perfusion parameters (from perfusion CT and dynamic enhanced magnetic resonance imaging, DCE-MRI) in the coagulation necrosis area, residual unablated area, untreated area, and normal control had been calculated by compared t- test. The correlation between f or D* with perfusion weighted CT including blood flow, BF (milliliter per 100 mL/min), blood volume, BV (milliliter per 100 mL/min), and capillary permeability–surface area, PMB (as a fraction) or from DCE-MRI: transfer constant (Ktrans), extra-vascular extra-cellular volume fraction (Ve) and reflux constant (Kep) values had been analyzed by region-of-interest (ROI) methods to calculate Pearson’s correlation coefficients.ResultsIn the ablated necrosis areas, f and D* significantly decreased and D significantly increased, compared with residual unblazed areas or untreated control groups and normal control groups (P < 0.001). The IVIM-DWI derived f parameters showed significant increases in the residual unablated tumor area. There was no significant correlations between f or D* and conventional perfusion parameters.ConclusionsThe IVIM-DW derived f, D and D* parameters have the potential to indicate therapy response immediately after RF Ablation treatment, while no significant correlations with classical tumor perfusion metrics were derived from DCE-MRI and perfusion-CT measurements.

Haematologic profile and histomorphologic assessment of the pancreas and liver of alloxan-induced diabetic rats treated with graded concentration of quail egg

This study was designed to investigate the effect of quail egg on the haematological parameters and the histopathology changes of the pancreas and liver of alloxan-induced diabetic Wistar albino male rats. Thirty albino rats with a mean weight of 160 ± 15 g were randomly selected into five groups, each with six rats. Groups 2, 3, 4 and 5 were induced with diabetes by intraperitoneal injection of alloxan at a dose of 160 mg/kg. Upon confirmation of diabetes (fasting blood sugar (FBS) >126 mg/dl), rats in groups 2, 3 and 4 were orally administered with 30, 15 and 7.5 mg/ml of quail egg. Group 1 and 5 rats were administered with distilled water to serve as positive and negative controls, respectively. The treatment lasted for 21 days, and blood samples for haematology [red blood cell (RBC), white blood cell (WBC), haemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV) and mean corpuscular haemoglobin concentration (MCHC)] analyses were collected on days 7, 14 and 21. On the 21st day, two rats per group were humanely sacrificed and the vital organs (pancreas and liver) were collected for histopathology. Haematologic results obtained showed marked reduction (p 0.05) in the WBC of the induced animals when compared with the positive control. However, on administration of the quail egg at 30 mg/ml, there was a significant increase (p 0.05). The histopathology of the pancreas of the untreated induced rats showed immense cytoplasmic vacuolation, while those treated with 30 mg/ml of quail egg showed mild cytoplasmic vacuolation. The liver histopathology of the untreated induced rats showed mononuclear leucocyte and multifocal areas of coagulative necrosis, while the rats treated with 30 mg/ml of quail egg showed no visible lesion. It can be concluded that quail egg possesses hepatoprotective property and also can improve haematologic profile of diabetic rats.

Radiofrequency Ablation: Inflammatory Changes in the Periablative Zone Can Induce Global Organ Effects, including Liver Regeneration.

To determine the kinetics of innate immune and hepatic response to the coagulation necrosis area that remains in situ after radiofrequency (RF) ablation, the cytokine profile of this response, and its local and global effect on the whole organ in a small-animal model. A standardized RF ablation dose (70°C for 5 minutes) was used to ablate more than 7% of the liver in 91 C57BL6 mice (wild type) according to a protocol approved by the animal care committee. The dynamic cellular response in the border zone surrounding ablation-induced coagulation and in the ablated lobe and an untreated lobe were characterized with immunohistochemistry 24 hours, 72 hours, 7 days, and 14 days after ablation (the time points at which cells migrate to necrotic tissues). After characterization of the cellular populations that reacted to the RF treatment, cytokines secreted by these cells were blocked, either by using interleukin-6 knockout mice (n = 24) or c-met inhibitor PHA 665752 (n = 15), to elucidate the key factors facilitating the wound healing response to RF ablation. Statistical significance was assessed with nonparametric analysis of variance. RF ablation induces a strong time-dependent immunologic response at the perimeter of the necrotic zone. This includes massive accumulation of neutrophils, activated myofibroblasts, and macrophages peaking at 24 hours, 7 days, and 14 days after ablation, respectively. In correlation with myofibroblast accumulation, RF ablation induced hepatocyte proliferation in both the ablated lobe and an untreated lobe (mean, 165.15 and 230.4 cyclin-dependent kinase 47-positive cells per ×20 field, respectively, at day 7; P < .02). Blockade of either IL-6 or c-met significantly reduced global hepatocyte proliferation (P < .05 for both), with the former reducing the accumulation of both macrophages and myofibroblasts surrounding the coagulation necrosis area (42.9 and 113.6 vs 7.3 and 46.6 macrophages and activated myofibroblasts per ×20 field, respectively; P < .036 for both). Hepatic RF ablation induces not only a local periablational inflammatory zone but also more global proliferative effects on the liver. These IL-6- and/or c-met-mediated changes could potentially account for some of the local and distant tumor recurrence observed after treatment.

Value of quantitative iodine-based material decomposition images with gemstone spectral CT imaging in the follow-up of patients with hepatocellular carcinoma after TACE treatment

To investigate the value of quantitative iodine-based material decomposition images with gemstone spectral CT imaging in the follow-up of patients with hepatocellular carcinoma (HCC) after transcatheter arterial chemoebolization (TACE). Consecutive 32 HCC patients with previous TACE treatment were included in this study. For the follow-up, arterial phase (AP) and venous phase (VP) dual-phase CT scans were performed with a single-source dual-energy CT scanner (Discovery CT 750HD, GE Healthcare). Iodine concentrations were derived from iodine-based material-decomposition images in the liver parenchyma, tumors and coagulation necrosis (CN) areas. The iodine concentration difference (ICD) between the arterial-phase (AP) and venal-phase (VP) were quantitatively evaluated in different tissues.The lesion-to-normal parenchyma iodine concentration ratio (LNR) was calculated. ROC analysis was performed for the qualitative evaluation, and the area under ROC (Az) was calculated to represent the diagnostic ability of ICD and LNR. In all the 32 HCC patients, the region of interesting (ROI) for iodine concentrations included liver parenchyma (n=42), tumors (n=28) and coagulation necrosis (n=24). During the AP the iodine concentration of CNs (median value 0.088 µg/mm(3)) appeared significantly higher than that of the tumors (0.064 µg/mm(3), P=0.022) and liver parenchyma (0.048 µg/mm(3), P=0.005). But it showed no significant difference between liver parenchyma and tumors (P=0.454). During the VP the iodine concentration in hepatic parenchyma (median value 0.181 µg/mm(3)) was significantly higher than that in CNs (0.140 µg/mm(3), P=0.042). There was no significant difference between liver parenchyma and tumors, CNs and tumors (both P>0.05). The median value of ICD in CNs was 0.006 µg/mm(3), significantly lower than that of the HCC (0.201 µg/mm(3), P<0.001) and hepatic parenchyma (0.117 µg/mm(3), P<0.001). The ICDs in tumors and hepatic parenchyma showed no significant difference (P=0.829). During the AP, the LNR had no significant difference between CNs and tumors (a median value 1.805 vs. 1.310, P=0.389), and during the VP, the difference was also non-significant (the median value 0.647 vs. 0.713, P=0.660). The mean Az value of ICDs for evaluation of surviving tumor tissues was 0.804, whiles LNR measured a disappointing result in both AV images and VP images. Quantitative iodine-based material decomposition images with gemstone spectral CT imaging can improve the diagnostic efficacy of CT imaging for HCC patients after TACE treatment.

I-FABP as biomarker for the early diagnosis of acute mesenteric ischemia and resultant lung injury.

Acute mesenteric ischemia (AMI) is a life-threatening condition that can result in multiple organ injury and death. A timely diagnosis and treatment would have a significant impact on the morbidity and mortality in high-risk patient population. The purpose of this study was to investigate if intestinal fatty acid binding protein (I-FABP) and α-defensins can be used as biomarkers for early AMI and resultant lung injury. C57BL/6 mice were subjected to intestinal ischemia by occlusion of the superior mesenteric artery. A time course of intestinal ischemia from 0.5 to 3 h was performed and followed by reperfusion for 2 h. Additional mice were treated with N-acetyl-cysteine (NAC) at 300 mg/kg given intraperitoneally prior to reperfusion. AMI resulted in severe intestinal injury characterized by neutrophil infiltrate, myeloperoxidase (MPO) levels, cytokine/chemokine levels, and tissue histopathology. Pathologic signs of ischemia were evident at 1 h, and by 3 h of ischemia, the full thickness of the intestine mucosa had areas of coagulative necrosis. It was noted that the levels of α-defensins in intestinal tissue peaked at 1 h and I-FABP in plasma peaked at 3 h after AMI. Intestinal ischemia also resulted in lung injury in a time-dependent manner. Pretreatment with NAC decreased the levels of intestinal α-defensins and plasma I-FABP, as well as lung MPO and cytokines. In summary, the concentrations of intestinal α-defensins and plasma I-FABP predicted intestinal ischemia prior to pathological evidence of ischemia and I-FABP directly correlated with resultant lung injury. The antioxidant NAC reduced intestinal and lung injury induced by AMI, suggesting a role for oxidants in the mechanism for distant organ injury. I-FABP and α-defensins are promising biomarkers, and may guide the treatment with antioxidant in early intestinal and distal organ injury.

Immunohistochemical and molecular study on the protective effect of curcumin against hepatic toxicity induced by paracetamol in Wistar rats.

BackgroundAn overdose of paracetamol is a frequent reason for liver and renal toxicity and possible death and curcumin has hepatoprotective properties against liver damage. The exact mechanism of such protection is not clear. Therefore, this study was conducted to examine the molecular levels of the protective effect of curcumin on paracetamol overdose induced hepatic toxicity in rats.MethodsMale Wistar rats were allocated into 4 groups. Control group, administered corn oil; curcumin group, administered curcumin (400 mg/kg BW daily intra-gastric) dissolved in corn oil; paracetamol group, administered corn oil with a single dose of paracetamol (500 mg/kg BW intra-gastric) and protective group, administered curcumin with a single dose of paracetamol. Curcumin was administered for 7 successive days, while paracetamol was administered at day six of treatment. Blood and liver tissues were collected for biochemical, histopathological, immunohistochemical and molecular examination.ResultsSerum analysis revealed an alteration in parameters of kidney and liver. A decrease in the antioxidant activity of liver was recorded in paracetamol group while curcumin administration restored it. Histopathological findings showed an extensive coagulative necrosis in hepatocytes together with massive neutrophilic and lymphocytic infiltration. Immunostaining of liver matrix metalloproteinase-8 (MMP-8) in paracetamol administered rats showed an increase in MMP-8 expression in the area of coagulative necrosis surrounding the central vein of hepatic lobules. Curcumin administration decreased MMP-8 expression in liver of paracetamol administered rats. Gene expression measurements revealed that paracetamol decreased the expression of antioxidant genes and increased the expression of interleukin-1β (IL-1β), IL-8, tumor necrosis factor-α (TNF-α) and acute phase proteins. Curcumin administration ameliorated paracetamol-induced alterations in genes expression of antioxidant and inflammatory cytokines.ConclusionThe results clarified the strong protective effect of curcumin on paracetamol induced hepatic toxicity in rats at the immunohistochemical and molecular levels.

Severe granulomatous gastric lesions following migration of Spiroxys contortus larvae (Nematoda: Spirurida) in European pond turtles, Emys orbicularis

Abstract The European pond turtle gradually disappeared from most of its range due to various factors. Hence, conservation measures are of main concern in all European countries where it is still present. A decent methodology for assessing the effect of parasites on the health of wildlife is microscopic lesion description. In 2002–2007, eight Emys orbicularis were brought for necropsy. The presence of gastric nematodes, identified as adults and larval Spiroxys contortus was noticed in all the turtles. A discrete cellular infiltrate with mononuclear cells and eosinophils was noticed in the gastric mucosa. The most prominent lesions were severe granulomas with or without degenerated larval structures. Some of the granulomas presented a central area of coagulation necrosis surrounded by giant cells, epithelioid cells and macrophages. In mature granulomas, the cluster of macrophage cell line and necrosis were surrounded by a fibrous capsule. Vascular cuffs, hyperemia, edema and venous ectasia were also present.

Identificação e distribuição de lesões cardíacas em bovinos intoxicados por Amorimia exotropica

Amorimia exotropica é um arbusto escandente que pertence à família Malpighiacea, cujo princípio tóxico é o monofluoracetato de sódio e possui ação cardiotóxica em bovinos. Ela é a única representante, na região Sul do país, do grupo de plantas que causam morte súbita associada ao exercício. Este trabalho identificou e mapeou as lesões cardíacas observadas em bovinos intoxicados naturalmente por A. exotropica. Selecionaram-se nove corações bovinos, provenientes de um surto de intoxicação natural pela planta em uma propriedade de gado de corte do Rio Grande do Sul e procedeu-se o mapeamento de oito regiões topográficas distintas (ápice, ventrículos direito e esquerdo, septo interventricular, músculos papilares direito e esquerdo e átrios direito e esquerdo). À avaliação macroscópica quatro bovinos apresentaram lesão focal e bem delimitada no músculo papilar esquerdo. Estas áreas na histologia correspondiam à necrose de coagulação em diferentes estágios de evolução, similares a infartos. Todos os bovinos apresentavam necrose de cardiomiócitos, caracterizadas por retração e hipereosinofilia citoplasmática e fragmentação celular em todas as áreas amostradas. A severidade da injúria celular foi avaliada pela imuno-histoquímica anti-troponina C, a qual demonstrou acentuada perda e/ou diminuição de marcação citoplasmática em células necróticas. O músculo papilar esquerdo foi a região mais acometida nos casos de intoxicação por Amorimia exotropica.

Association between Kikuchi-Fujimoto disease and Streptococcus pneumoniae infection

Abstract Kikuchi-Fujimoto disease is a rare histiocytic necrotizing lymphadenitis that affects typically young women causing fever and painful laterocervical lymphadenopathy. The etiology is unknown, but several viral infections and autoimmune diseases have been related with the disease. Bacterial infections are less frequent. Diagnosis needs for excisional lymph node biopsy that shows paracortical areas of coagulative necrosis with abundant debris, distortion of the nodal architecture, and a large amount of histiocytes at the margins of the necrotic areas. There is no specific treatment for the disease. We present the case of a young woman with Kikuchi-Fujimoto disease associated with lower respiratory tract infection by Streptococcus pneumoniae and review the literature.

In vivo experimental study on the effects of fluid in increasing the efficiency of radiofrequency ablation.

Radiofrequency ablation (RFA) is the most widely used and studied method internationally for the local treatment of liver tumors. However, the extension of coagulation necrosis in one RFA procedure is limited and incomplete coverage of the damaged area can lead to a high local recurrence rate. In this study, we compared the effects of different solutions in enhancing hepatic radiofrequency by establishing a rabbit VX2 liver cancer model. We also determined the optimal solution to maximise effects on the extent of RFA-induced coagulation necrosis. Thirty VX2 tumor rabbits were randomly assigned to five groups: group A, RFA alone; group B, RFA with anhydrous ethanol injection; group C, RFA with 5% hypertonic saline injection; group D, RFA with lidocaine injection; and group E, RFA with a mixed solution. Routine ultrasound examinations and contrast-enhanced ultrasound (CEUS) of the ablation areas were performed after RFA. Then, we measured the major axis and transverse diameter and compared the areas of coagulation necrosis induced by RFA. The mean ablation area range increased in groups B, C and especially E, and the scopes were greater compared with group A. Preoperative application of anhydrous ethanol, hypertonic saline, lidocaine and the mixed solution (groups B, C, D and E, respectively) resulted in larger coagulation necrosis areas than in group A (p<0.05). Among the groups, the coagulation necrosis areas in group E was largest, and the difference was statistically significant compared with other groups (p<0.05). Pathological findings were consistent with imaging results. A mixture of dehydrated alcohol, hypertonic saline and lidocaine injected with RFA increases the extent of coagulation necrosis in the liver with a single application, and the mixed solution is more effective than any other injection alone.

The peculiar ultrasonographic and elastographic features of thyroid nodules after treatment with laser or radiofrequency: similarities and differences

The aim of percutaneous thermal ablation with laser (LA) or radiofrequency (RFA) is to reduce the volume of benign thyroid nodules. Little is known about ultrasonographic and elastographic appearances of thyroid lesions after treatment. For the first time, we report in detail the main ultrasonographic and elastographic characteristics of thermally ablated nodules and their underlying similarities and differences. Both thermal treatments usually produce a marked hypoechoic area of coagulative necrosis. LA-treated lesions usually become highly heterogeneous due to the presence of cavitations and charring; they then evolve into hyperechoic scars. In RFA-treated nodules, instead, the necrotic area is more homogeneous but presents more irregular margins compared to those observed in LA-treated lesions. Regardless of the thermal method used, vascularity is typically reduced in all treated nodules and stiffness, evaluated with qualitative elastography, increases. In conclusion, ultrasonographic and elastographic appearances of the thermally ablated thyroid lesions differ slightly according to the adopted procedure. Furthermore, they are peculiar, changeable over time, and potentially misleading.

A synthetic tryptophan metabolite reduces hemorrhagic area and inflammation after pulmonary radiofrequency ablation in rabbit nonneoplastic lungs

The purpose of this study was to determine the effect of a synthetic tryptophan metabolite, tranilast [N-(3,4-dimethoxycinnamoyl)-anthranilic acid], on inflammatory and hemorrhagic areas after pulmonary radiofrequency ablation (RFA) in rabbits. Percutaneous RFA using a 17-gauge LeVeen electrode was performed in normal rabbit lungs. The rabbits were divided into tranilast-treated (300mg/kg/day, orally) and control groups (n=24/group). The effects of tranilast were evaluated using multidetector-row computed tomography (CT), histology, and immunohistochemistry immediately after RFA on days 1, 7, 14, and 28. Oral administration of tranilast significantly reduced the size of ablated lesions assessed using CT and histology on days 7 and 14. Furthermore, it reduced the hemorrhagic areas on day 7 and inflammatory areas on day 14, but did not affect the areas of coagulation necrosis on days 1, 7, 14, and 28. Immunohistochemical analysis showed an increase in the ratio of CD163-positive macrophage areas to rabbit macrophage (RAM11)-positive pan-macrophage areas and a decrease in the number of nuclear factor-κB-positive nuclei and CD31-positive microvessels in the tranilast group on days 7 and/or 14. The results suggest that tranilast modulates the repair process after pulmonary RFA through macrophage accumulation, suppression of inflammation, and angiogenesis.

Real time shear waves elastography monitoring of thermal ablation: in vivo evaluation in pig livers

BackgroundThermal ablation is a widely used minimally invasive treatment modality for different cancers. However, lack of a real-time imaging system for accurate evaluation of the procedure is one of the reasons of local recurrences. Shear waves elastography (SWE) is a new ultrasound (US) imaging modality to quantify tissue stiffness. The aim of the study was to assess the feasibility and accuracy of US elastography for quantitative monitoring of thermal ablation and to determine the elasticity threshold predictive of coagulation necrosis. MethodsA total of 29 in vivo thermal lesions were performed in pig livers with radiofrequency system. SWE and B-mode images were acquired simultaneously. Liver elasticity was quantified by using SWE data and expressed in kilopascal. After the procedure, pathologic analysis of treated tissues was compared with US images. The sensitivity and positive predictive value of the SWE maps of tissue elasticity were calculated and compared with the boundaries of the pale coagulation necrosis areas found at pathology. ResultsThe liver mean elasticity values before and after thermal therapy were 6.4 ± 0.3 and 38.1 ± 2.5 kPa, respectively (P < 0.0001). For a threshold of 20 kPa, sensitivity (i.e., the rate of pixels correctly detected as necrosed tissue) was 0.8, and the positive predictive value (i.e., the rate of pixels in the elastographic map >20 kPa that actually developed coagulation necrosis) was 0.83. ConclusionsTissue areas with coagulation necrosis are significantly stiffer than the surrounding tissue. SWE permits the real-time detection of coagulation necrosis produced by radiofrequency and could potentially be used to monitor US-guided thermal ablation.

Ultrasound-guided Ablative Therapy for Hepatic Malignancies: a Comparison of the Therapeutic Effects of Microwave and Radiofrequency Ablation

Background: Radiofrequency ablation (RFA) is currently the most widely used thermal ablative technique for unresectable hepatic malignancies. However, microwave ablation (MWA) is also gaining popularity worldwide. With a cooled-tip electrode, MWA produces necrotic effects comparable to RFA without damaging soft tissues along the electrode track. In this study, the authors compared the efficacy of these two ablative modalities in the treatment of primary or secondary liver cancer.Materials and methods: Ultrasound-guided MWA was employed to treat 230 cases of liver cancer with a total of 349 nodules and a diameter of 0.8-11.4 cm [mean: 5.7 ± 2.1 cm]. Meanwhile, ultrasound-guided RFA was performed in 92 cases of liver cancer with 173 nodules in total and a diameter of 2.0-10.2 cm [mean: 5.4 ± 1.9 cm]. The clinical data were retrospectively analyzed to identify the differences between MWA and RFA in terms of their operative safety, local ablative effect, cost efficiency, and cumulative survival rate.Results: The patient parameters were comparable. The area of coagulative necrosis was similar in both groups. The tumor complete ablation rate was 83.7% (292/349) for the MWA group and 86.7% (150/173) for the RFA group, which showed no significant difference (P = 0.75). The one-year and two-year cumulative survival rate were all comparable between the two groups (P = 0.66, P = 0.41), which were 90.0% (198/220), 81.6% (120/147) for the MWA group, and 91.8% (78/85), 81.0% (34/42) for the RFA group, respectively. Moreover, both the tumor type and number had no influence on survival rate for the two methods. In addition, there was no significant difference in complication rates between the two groups. The cost for performing one MWA procedure was about 40% lower than that of RFA ($1200 vs $2000). Conclusions: Both MWA and RFA are safe and effective ablative treatments for liver cancer. Additionally, MWA has the advantage of cost efficiency.

Corpuscular thymoma, case report and review of literature

Aim Hassall corpuscles are concentric arrangement of keratinizing epithelial cells that are restricted to the medulla of the normal thymus. Hassall corpuscles in thymomas are unusual findings and are seen in thymomas WHO type B1-3 with medullary differentiation, but rare cases have been documented. Thymoma with abundant Hassall corpuscles (corpuscular thymoma) must be differentiated from thymic carcinoma, well differentiated keratinizing squamous cell carcinoma type. Case report We report a case of a 73-year-old male patient, presenting with cough for one year. Computed tomography (CT) scan showed a well defined anterior superior mediastinal mass. Surgical excision of the mass was performed. Gross examination revealed a large, oval shaped, well circumscribed, encapsulated, firm brown mass measuring 10 × 6 × 4 cm, and weighing 219 g, with heterogeneous pale white solid, small cystic spaces, and necrotic cut surfaces. Light microscopic examination revealed two alternating components, the first forming a delicate loose network of neoplastic epithelium equally admixed with non-neoplastic lymphocytes, and the second forming vague solid sheets with paucity of lymphocytes. Both components show abundant Hassall corpuscles, extensive areas of coagulative tumor necrosis, small cystic spaces, and cholesterol clefts. Immunohistochemical studies showed that the neoplastic epithelium is strongly and diffusely immunoreactive for HMWCK, panCK, and EMA, and focally positive for CAM5.2, and negative for CD5, and C-KIT immunohistochemical stains. Conclusion Corpuscular thymoma reported in the literature as WHO type B2 or B3. Our presented case is of type B3, Modified Masoaka stage 1. We believe that thymoma with corpuscular differentiation is a rare distinct variant of organotypical thymomas, although it is not mentioned in the 2004 WHO classification. Recognition of this rare variant of thymomas is very important to avoid confusion with thymic carcinoma and squamous cell carcinoma type. Careful microscopic examination and immunohistochemical stains are mandatory to differentiate between these entities.