Percutaneous High-Energy Microwave Ablation for the Treatment of Pulmonary Tumors: A Retrospective Single-Center Experience.

PURPOSE: To evaluate the safety and efficacy of percutaneous high-energy microwave ablation (MWA) for the treatment for pulmonary tumors. MATERIALS AND METHODS: A retrospective review was undertaken of 44 patients (21 men, 23 women; median age, 66 y; range, 17-89 y) who underwent 62 sessions of high-energy MWA for 87 pulmonary tumors at a single tertiary referral center between June 2012 and June 2014. Primary tumor origin was sarcoma (n = 23), colorectal (n = 16), lung (n = 2), esophageal (n = 1), breast (n = 1), and bladder (n = 1). Median tumor size was 12 mm (range, 6-45 mm). Technical success was recorded contemporaneously, complication rate at 30 days was recorded prospectively, and technique effectiveness was assessed by longitudinal follow-up CT scan. RESULTS: Primary technical success was achieved in 94% of ablation sessions. The median follow-up interval was 15 months (range, 6.2-29.5 mo) during which time local tumor progression was observed in two of 87 tumors (technique effectiveness 98%). Pneumothorax requiring chest tube insertion occurred in 19%; delayed pneumothorax occurred in four patients. No hemoptysis, infection, or other complications were recorded. CONCLUSIONS: High-energy MWA is safe and effective for the destruction of lung tumors.

Arterial spin-labeling MR imaging of cerebral hemorrhages.

INTRODUCTION: The purpose of this study is to identify the characteristics of brain perfusion measured by arterial spin-labeling magnetic resonance imaging (ASL-MRI) in cerebral hemorrhages. METHODS: Brain blood flow values (CBF-ASL values) for cerebral and cerebellar hemispheres and segmented cerebral regions were measured by ASL-MRI in 19 putaminal hemorrhage patients and 20 thalamic hemorrhage patients in acute or subacute stages. We assessed the lateralities of CBF-ASL values and the relationships between CBF-ASL values and other imaging findings and clinical manifestations. RESULTS: Both the 19 putaminal hemorrhage patients and the 20 thalamic hemorrhage patients had significantly low CBF-ASL values of the contralateral cerebellum in subacute stage, suggesting that ASL-MRI might delineate crossed cerebellar diaschisis (CCD). Ipsilateral low CBF-ASL values were observed in frontal lobes and thalami with a putaminal hemorrhage and lentiform nuclei, temporal lobes, and parietal lobes with a thalamic hemorrhage, suggesting that ASL-MRI showed the ipsilateral cerebral diaschisis (ICD). In the putaminal hemorrhage patients, the hematoma volume negatively affected both the bilateral cerebellar and cerebral hemispheric CBF-ASL values. In the thalamic hemorrhage patients, a concomitant intraventricular hemorrhage caused low cerebral hemispheric CBF-ASL values. CONCLUSION: The use of ASL-MRI is sensitive to the perfusion abnormalities and could thus be helpful to estimate functional abnormalities in cerebral hemorrhage patients.

Conservative management of spontaneous spinal epidural hematoma: A case report with favorable prognosis.

Sudden spinal epidural hematoma (SSEH) is relatively rare. Sudden pain from the neck to the back and subsequent extremity paralysis necessitate immediate head and cervical magnetic resonance imaging or computed tomography, keeping SSEH in mind. Although surgery is recommended for progressive paralysis, conservative treatment is indicated for mildly symptomatic cases.

Spinal subdural hematoma with sudden onset of paraplegia in a patient on oral anticoagulant therapy.

Spinal subdural hematoma is uncommon but may become more prevalent with increasing anticoagulant use. Early diagnosis from symptoms like lower back pain and leg paralysis is crucial for timely intervention.

A case of bleeding shock induced by injury of the intercostal artery following percutaneous nephrolithotripsy.

Introduction: The risk of postoperative bleeding complications should be concerned to perform percutaneous nephrolithotripsy. Most of the vascular injuries occurred at the peripheral renal artery in the previous reports. We experienced a case of bleeding shock induced by the injury of the intercostal artery in the abdominal wall following percutaneous nephrolithotripsy. Case presentation: A 56-year-old woman had been in the bleeding shock status on the 2nd day after percutaneous nephrolithotoripsy. Emergently, contrast-enhanced computed tomography was performed and extravasation of contrast agents was seen in the abdominal wall. Injuries of the intercostal artery were identified in the angiography and controlled by transcatheter arterial embolization. Conclusion: The intercostal arteries could be injured in the anterolateral zone of the abdominal wall over the end of the ribs. Contrast-enhanced computed tomography was useful to detect the bleeding point. Transcatheter arterial embolization was an effective and safe method to control bleedings from them.

Retrospective analysis of contrast-enhanced computed tomographic findings related to obstructive shock due to ascending aortic dissection.

OBJECTIVE: The objective of this study was to evaluate contrastenhanced computed tomography findings related to obstructive shock due to ascending aortic dissection (AAD). METHODS: The computed tomography findings in 9 AAD patients with shock, 11 AAD patients without shock, and 18 control subjects were evaluated for (1) pericardial effusion, (2) diameter of the inferior vena cava, (3) periportal hypodensity, (4) retrograde reflux of contrast material, (5) aortic and visceral enhancement, and (6) other factors (peripancreatic edema, bowel thickening/dilatation). RESULTS: Patients with shock showed the highest ratio of pericardial effusion, periportal hypodensity, and retrograde reflux of contrast material; largest inferior vena cava diameter; stronger aortic enhancement in both the arterial and portal phases; lowered splenic and pancreatic enhancement in the arterial phase; and stronger visceral (especially adrenal) enhancement, except for the renal medulla in the portal phase. CONCLUSIONS: Computed tomography findings related to obstructive shock due to AAD reflected impaired diastolic filling, decreased cardiac output, and flow redistribution in visceral organs.

High b-value diffusion-weighted MRI in differentiation between benign and malignant polypoid gallbladder lesions.

BACKGROUND: Several studies have reported the effectiveness of high b-value diffusion-weighted MR imaging (DWI) in the abdominal region, and have found that various malignant tumors may show high signal intensity on DWI, reflecting their high cellularity and/or their long relaxation time. The value of ADC measurement has also been documented for the diagnosis of several abdominal malignancies. PURPOSE: To retrospectively evaluate the usefulness of high b-value DWI in differentiating between benign and malignant polypoid gallbladder lesions. MATERIAL AND METHODS: The study population consisted of 10 benign (three hyperplastic polyps and seven adenomas) and 13 malignant (all adenocarcinomas) polypoid gallbladder lesions. DWI was evaluated by two observers. Qualitatively, the signal intensity of the lesions on DWI was visually evaluated and categorized as iso, high, or very high. Quantitatively, the ADC values of the lesions were measured from ADC maps. Statistical analysis was performed using a two-tailed Fisher's exact test and the Mann-Whitney test, respectively. RESULTS: Qualitative analysis revealed a statistical difference (P = 0.0041). Six of 10 benign lesions were categorized as iso, and the remaining four were categorized as high. In the 13 malignant lesions, one was categorized as iso, five as high, and seven as very high. The ADC values of the malignant lesions (1.34 ± 0.50 × 10(-3) mm(2)/sec) were significantly lower than those of the benign lesions (2.26 ± 0.44 × 10(-3) mm(2)/sec) (P = 0.00016). CONCLUSION: High b-value DWI may be useful for differentiating between benign and malignant polypoid gallbladder lesions by the visual assessment of DWI and ADC measurement.

Aneurismal type of colorectal cancer: imaging characteristics of gastrointestinal endoscopy, computed tomography and magnetic resonance imaging.

BACKGROUND/AIMS: Only a few studies have investigated aneurismal large-intestinal malignant diseases. The present study reported five cases of aneurismal colon cancer that were experienced over 20 years. The present study aims to define the pathological and diagnostic imaging characteristics of aneurismal colon cancer. METHODOLOGY: A case series from a retrospective review of large-intestinal malignant tumors at Saga Medical School, Japan. Barium enema was performed in 876 patients with large-intestinal advanced cancer, which included five with aneurismal-type cancer. RESULTS: The characteristics of the 5 cases were as follows: (i) pathological findings were poorly differentiated adenocarcinoma without desmoplastic change or mucinous adenocarcinoma; (ii) a typical aneurismal type revealed by barium enema had a low elevated tumor edge without stenosis upon endoscopic examination; (iii) computed tomography showed low attenuation without enhancement of contrast material; and (iv) magnetic resonance imaging indicated high intensity in the T2-weighted images of mucinous adenocarcinoma. CONCLUSION: We revealed 5 cases of aneurismal colon cancer, which had characteristic pathological findings and diagnostic imaging, and poor prognosis.

FIB-4 index-based surveillance for advanced liver fibrosis in diabetes patients.

Liver fibrosis is associated with lifestyle-related diseases, including diabetes. The identification of diabetic patients with severe liver fibrosis is important, but a simple and reliable diagnostic procedure remains to be determined. We conducted an observational study to evaluate the performance of a FIB-4 index-based screening strategy for the diagnosis of advanced liver fibrosis in patients with diabetes or prediabetes. Two hundred and forty-two patients underwent abdominal imaging in our Study. According to the abdominal imaging findings, fatty liver, liver cirrhosis, and hepatocellular carcinoma were defined, and their association with FIB-4 index evaluated. The prevalences of liver cirrhosis and hepatocellular carcinoma in patients with a high (≥ 2.67; liver cirrhosis: 42.9%, hepatocellular carcinoma: 14.3%) FIB-4 index were significantly higher than in those with an intermediate (1.3 ≤ FIB-4 < 2.67; liver cirrhosis: 1.6%, hepatocellular carcinoma: 0.8%) or low FIB-4 index (< 1.3; liver cirrhosis: 1.2%, hepatocellular carcinoma: 0%). The diagnostic accuracy, specificity, and sensitivity of the FIB-4 index for the diagnosis of liver cirrhosis or hepatocellular carcinoma were 84.3%, 85.5%, and 89.3%, respectively, with an optimized cut-off value of 2.96 (sensitivity = 0.86, specificity = 0.98). Using an optimized cut-off value, FIB-4 index might be useful to identify liver cirrhosis or hepatocellular carcinoma in diabetes patients with high diagnostic accuracy.

A case of osimertinib-resistant lung adenocarcinoma responded effectively to alternating therapy.

We report a case of initial lung adenocarcinoma in which transformation to small cell lung carcinoma (SCLC) was observed after acquired resistance to the 3rd generation epidermal growth factor receptor tyrosine kinase inhibitor (EGFR-TKI) osimertinib and alternating treatment between chemotherapy and osimertinib was effective. A 61-year-old woman with EGFR mutation positive stage IV lung adenocarcinoma was administered 1st generation EGFR-TKI for 8 months as the first line therapy, then chemotherapy and 2nd generation EGFR-TKI after progressive disease (PD). Four years after initial diagnosis, EGFR T790M was detected in a metastatic lesion of the right thoracic wall and osimertinib was prescribed. Although partial response (PR) was achieved, a new metastatic lesion appeared in the right pleurum near the diaphragm, in which SCLC characteristics were observed with elevation of pro-gastrin-releasing peptide (pro-GRP) at the time of PD under osimertinib. Osimertinib was discontinued and carboplatin plus irinotecan chemotherapy was chosen as the next treatment, leading to PR after 2 cycles. Subsequently, the right thoracic wall tumor harboring T790M and the right pleural tumor near the diaphragm showing transformation to SCLC exhibited opposite responses to therapy alternating between osimertinib and chemotherapy. It is concluded that extended disease control can be achieved by combining appropriate treatments according to the mechanisms of resistance inferred from precise genetic and pathological examination in real time.

Current Status and Problems of T790M Detection, a Molecular Biomarker of Acquired Resistance to EGFR Tyrosine Kinase Inhibitors, with Liquid Biopsy and Re-biopsy.

BACKGROUND/AIM: The purpose of this study was to consider appropriate application of liquid and re-biopsy through analysis of current status in practice. PATIENTS AND METHODS: We performed a retrospective analysis of 22 patients with epidermal growth factor receptor (EGFR) mutation-positive non-small cell lung cancer who exhibited 1st/2nd generation EGFR-tyrosine kinase inhibitors resistance. The cobas® method was used to detect T790M with re-biopsy and the mutation-biased PCR and quenched probe method was used with liquid biopsy. RESULTS: T790M detection rate was 52% with re-biopsy and 58% with liquid biopsy. The concordance between tissue and plasma was 58%. One patient who was T790M-positive with liquid biopsy showed heterogeneity among metastatic lesions in terms of osimertinib efficacy, as revealed by T790M detection with re-biopsy. CONCLUSION: Liquid biopsy reflects the whole body, whereas re-biopsy is useful for spatial diagnosis. Considering these characteristics, a combination of liquid and re-biopsy contribute to enhanced treatment.

Noninvasive method for mapping CVR in moyamoya disease using ASL-MRI.

PURPOSE: To project a noninvasive method for mapping cerebrovascular reserve (CVR) in moyamoya disease (MMD) using ASL-MRI. METHODS: 16 MMD patients underwent cerebral blood flow (CBF) examinations by standard ASL-MRI, pulse-wave-synchronized ASL-MRI (pulsy ASL-MRI) which tagged the arterial blood coincident with a peak of a pulse wave, and single photon emission computed tomography (SPECT) imagings with iodine-123-N-isopropyl-p-iodoamphetamine in the resting (rest-IMP) and after acetazolamide challenge (ACZ-IMP). Hemispheric 32-sided cerebral blood flow (CBF) values were measured with normalized CBF maps created from standard ASL-MRI (standard-ASL value), pulsy ASL-MRI (pulsy-ASL value), rest-IMP (rest-IMP value), and ACZ-IMP (ACZ-IMP value). CVR based on rest-IMP and ACZ-IMP values (IMP-CVR) was calculated. ASL-CVR was also calculated on the basis of corrected standard-ASL values and pulsy-ASL values, which were adjusted to the ACZ-IMP values and rest-IMP values, respectively, by the least-squares method. We assessed the relationships between rest-IMP values and pulsy-ASL values, ACZ-IMP values and standard-ASL values, and IMP-CVR and ASL-CVR. RESULTS: Significant relationships were observed between rest-IMP values and pulsy-ASL values (correlation coefficient (r=0.557, p<0.01)), ACZ-IMP values and standard-ASL values (r=0.825, p<0.01), and IMP-CVR and ASL-CVR (r=0.736, p<0.01). CONCLUSIONS: ASL-MRI is equivalent to SPECT and that it might serve as a noninvasive method for mapping CVR in MMD.

A technical perspective for understanding quantitative arterial spin-labeling MR imaging using Q2TIPS.

We illustrate the fundamental theoretical principles of arterial spin-labeling (ASL) magnetic resonance imaging (MRI) and show a system that employs the second version of quantitative imaging of perfusion using a single subtraction (Q2TIPS) to quantify cerebral blood flow (CBF). We also discuss the effects of the parameters used in Q2TIPS on CBF values as measured with ASL-MRI.

Operative strategy for descending and thoracoabdominal aneurysm repair with preoperative demonstration of the Adamkiewicz artery.

BACKGROUND: Our study aimed to demonstrate the efficacy of preoperative intraarterial computed tomographic angiography to identify the Adamkiewicz artery (AKA). We also aimed to investigate the impact of identification of the AKA on the strategy for preventing spinal cord injury. METHODS: Thirty-seven patients (24 cases of descending aortic aneurysms and 13 cases of thoracoabdominal aortic aneurysms), were studied. Average age was 63.8 years old. A pigtail catheter was inserted into the descending aorta and its tip was located immediately below the left subclavian artery. Subsequently, intraarterial computed tomographic angiography was performed and the segmental artery to the AKA was identified. Aneurysms were replaced electively with prosthetic graft in all cases. In cases where the aortic segment that supplied the AKA was cross-clamped, the identified segmental artery-AKA was selectively perfused. In these cases, the segmental artery-AKA was reconstructed with an interposition graft. RESULTS: Intraarterial computed tomographic angiography successfully identified the segmental artery-AKA in all patients. The average number of AKA observed per patient was 1.3± 0.6 AKAs. Selective perfusion of preoperatively identified segmental artery-AKAs was performed in 11 cases. The average number of reconstructed segmental arteries was 0.5 in descending aortic aneurysms and 1.7 in thoracoabdominal aortic aneurysms. Although paraparesis occurred in two patients (5%), the remaining 35 patients did not suffer spinal cord injury. CONCLUSIONS: Intraarterial computed tomographic angiography reliably identifies the segmental-AKA. Furthermore, selective perfusion of the segmental artery-AKA, based on accurate preoperative identification, might be one option for preventing intraoperative spinal cord ischemia.

A hepatocellular neoplasm accompanied with massive histiocyte infiltration.

This report presents the case of a unique hepatocellular nodule occurring in a 73-year-old Japanese male with diabetes mellitus and mild obesity. The nodule consisted of hepatocyte-like tumor cells and abundant foam cell type histiocytes that filled up a sinusoid-like space and formed central loose fibrosis. The superficial area did not contain as many histiocytes and showed hepatocellular adenoma character, but there was a focal hepatocellular carcinoma-like lesion, thus suggesting hepatocellular adenoma with malignant transformation. The background liver showed an almost normal histology except for mild steatosis with no specific infiltration of macrophages. These macrophages contained abundant fat droplets, whereas the tumor cells had no fat droplets. The expressions of monocyte chemoattractant protein-1 and macrophage colony-stimulating factor were significantly higher in the tumor than in the background liver. These findings suggested such macrophage infiltration induced by the tumor cells and these macrophages probably phagocytosed surplus fat at the intercellular space of this unique tumor.