Diagnosis of Acute Pancreatitis Using Postmortem Computed Tomography and Postmortem Magnetic Resonance Imaging: A Case Report and a Review of Literature.

ABSTRACT: Acute pancreatitis (AP) is inflammation of the pancreas, which may be due to a wide variety of etiologies that share a final common pathway of premature activation of pancreatic enzymes and resultant autodigestion of pancreatic parenchyma. Acute pancreatitis is easy to diagnose clinically, with the presence of at least 2 of the 3 criteria (upper abdominal pain, serum amylase or lipase level greater than 3 times the upper limit of normal, or characteristic findings on imaging studies) of the revised Atlanta classification. However, postmortem imaging examinations of pancreatitis are extremely rare, and very few successful cases have been reported. Here, we present a case report of a single patient who underwent autopsy and postmortem imaging. Postmortem computed tomography (PMCT) and postmortem magnetic resonance imaging (PMMRI) showed peripancreatic inflammation and acute peripancreatic fluid collection in the left anterior pararenal space, which is consistent with the examination by autopsy. The advantages of PMMRI in AP have also been demonstrated. Our study also confirmed the advantage of PMCT angiography in the diagnosis of AP. To the best of our knowledge, this is the first report of PMCT and PMMRI combined with postmortem pathology in the diagnosis of AP.

Radiomics nomogram for the prediction of microvascular invasion of HCC and patients' benefit from postoperative adjuvant TACE: a multi-center study.

OBJECTIVES: To evaluate the performance of a radiomics nomogram developed based on gadolinium-ethoxybenzyl-diethylenetriamine penta-acetic acid (Gd-EOB-DTPA) MRI for preoperative prediction of microvascular invasion (MVI) of hepatocellular carcinoma (HCC), and to identify patients who may benefit from the postoperative adjuvant transarterial chemoembolization (PA-TACE). METHODS: A total of 260 eligible patients were retrospectively enrolled from three hospitals (140, 65, and 55 in training, standardized external, and non-standardized external validation cohort). Radiomics features and image characteristics were extracted from Gd-EOB-DTPA MRI image before hepatectomy for each lesion. In the training cohort, a radiomics nomogram which incorporated the radiomics signature and radiological predictors was developed. The performance of the radiomics nomogram was assessed with respect to discrimination calibration, and clinical usefulness with external validation. A score (m-score) was constructed to stratify the patients and explored whether it could accurately predict patient who benefit from PA-TACE. RESULTS: A radiomics nomogram integrated with the radiomics signature, max-D(iameter) > 5.1 cm, peritumoral low intensity (PTLI), incomplete capsule, and irregular morphology had favorable discrimination in the training cohort (AUC = 0.982), the standardized external validation cohort (AUC = 0.969), and the non-standardized external validation cohort (AUC = 0.981). Decision curve analysis confirmed the clinical usefulness of the novel radiomics nomogram. The log-rank test revealed that PA-TACE significantly decreased the early recurrence in the high-risk group (p = 0.006) with no significant effect in the low-risk group (p = 0.270). CONCLUSIONS: The novel radiomics nomogram combining the radiomics signature and clinical radiological features achieved preoperative non-invasive MVI risk prediction and patient benefit assessment after PA-TACE, which may help clinicians implement more appropriate interventions. CLINICAL RELEVANCE STATEMENT: Our radiomics nomogram could represent a novel biomarker to identify patients who may benefit from the postoperative adjuvant transarterial chemoembolization, which may help clinicians to implement more appropriate interventions and perform individualized precision therapies. KEY POINTS: • The novel radiomics nomogram developed based on Gd-EOB-DTPA MRI achieved preoperative non-invasive MVI risk prediction. • An m-score based on the radiomics nomogram could stratify HCC patients and further identify individuals who may benefit from the PA-TACE. • The radiomics nomogram could help clinicians to implement more appropriate interventions and perform individualized precision therapies.

Recurrent chondrosarcoma of the larynx: A case report and literature review.

BACKGROUND: Laryngeal chondrosarcoma (LCS) is a rare laryngeal tumor that most commonly originates from the cricoid cartilage. The current trend for treatment of low-grade LCS is function-sparing surgical option with negative margins. CASE SUMMARY: We reported here a case of a 63-year-old male patient with a 3-month history of progressive hoarseness and throat pain. The patient had undergone surgical resection of a laryngeal mass 2 years prior. A supracricoid partial laryngectomy was performed this time. Histological examination supported the diagnosis of low-grade chondrosarcoma. Three years later, the radiological and clinical findings showed no evidence of recurrence. CONCLUSION: Currently, total laryngectomy is preferred for patients with recurrent low-grade LCS. However, the literature review and our case suggest that a second function-preserving procedure may be a reasonable choice for recurrent LCS.

Diffusion-weighted magnetic resonance imaging without bowel preparation for detection of ulcerative colitis.

AIM: To evaluate the accuracy of diffusion-weighted imaging (DWI) without bowel preparation, the optimal b value and the changes in apparent diffusion coefficient (ADC) in detecting ulcerative colitis (UC). METHODS: A total of 20 patients who underwent 3T magnetic resonance imaging (MRI) without bowel preparation and colonoscopy within 24 h were recruited. Biochemical indexes, including C-reactive protein (CRP), erythrocyte sedimentation rate, hemoglobin, leucocytes, platelets, serum iron and albumin, were determined. Biochemical examinations were then performed within 24 h before or after MR colonography was conducted. DWI was performed at various b values (b = 0, 400, 600, 800, and 1000 s/mm(2)). Two radiologists independently and blindly reviewed conventional- and contrast-enhanced MR images, DWI and ADC maps; these radiologists also determined ADC in each intestinal segment (rectum, sigmoid, left colon, transverse colon, and right colon). Receiver operating characteristic (ROC) analysis was performed to assess the diagnostic performance of DWI hyperintensity from various b factors, ADC values and different radiological signs to detect endoscopic inflammation in the corresponding bowel segment. Optimal ADC threshold was estimated by maximizing the combination of sensitivity and specificity. MR findings were correlated with endoscopic results and clinical markers; these findings were then estimated by ROC analysis. RESULTS: A total of 100 segments (71 with endoscopic colonic inflammation; 29 normal) were included. The proposed total magnetic resonance score (MR-score-T) was correlated with the total modified Baron score (Baron-T; r = 0.875, P < 0.0001); the segmental MR score (MR-score-S) was correlated with the segmental modified Baron score (Baron-S; r = 0.761, P < 0.0001). MR-score-T was correlated with clinical and biological markers of disease activity (r = 0.445 to 0.831, P < 0.05). MR-score-S > 1 corresponded to endoscopic colonic inflammation with a sensitivity of 85.9%, a specificity of 82.8% and an area under the curve (AUC) of 0.929 (P < 0.0001). The accuracy of DWI hyperintensity was significantly greater at b = 800 than at b = 400, 600, or 1000 s/mm(2) (P < 0.05) when endoscopic colonic inflammation was detected. DWI hyperintensity at b = 800 s/mm(2) indicated endoscopic colonic inflammation with a sensitivity of 93.0%, a specificity of 79.3% and an AUC of 0.867 (P < 0.0001). Quantitative analysis results revealed that ADC values at b = 800 s/mm(2) differed significantly between endoscopic inflamed segment and normal intestinal segment (1.56 ± 0.58 mm(2)/s vs 2.63 ± 0.46 mm(2)/s, P < 0.001). The AUC of ADC values was 0.932 (95% confidence interval: 0.881-0.983) when endoscopic inflammation was detected. The threshold ADC value of 2.18 × 10(-3) mm(2)/s indicated that endoscopic inflammation differed from normal intestinal segment with a sensitivity of 89.7% and a specificity of 80.3%. CONCLUSION: DWI combined with conventional MRI without bowel preparation provides a quantitative strategy to differentiate actively inflamed intestinal segments from the normal mucosa to detect UC.

3.0T ¹H magnetic resonance spectroscopy for assessment of steatosis in patients with chronic hepatitis C.

AIM: To investigate the utility of (1)H magnetic resonance spectroscopy ((1)H MRS) as a noninvasive test for steatosis in patients infected with hepatitis C virus. METHODS: Ninety patients with chronic hepatitis C and pathology data underwent 3.0T (1)H MRS, and the results of MRS and pathological analysis were compared. RESULTS: This group of patients included 26 people with mild fatty liver (28.89%), 16 people with moderate fatty liver (17.78%), 18 people with severe fatty liver (20.0%), and 30 people without fatty liver (33.33%). The water peak was near 4.7 parts per million (ppm), and the lipid peak was near 1.3 ppm. Analysis of variance revealed that differences in the lipid peak, the area under the lipid peak, ratio of the lipid peak to the water peak, and ratio of the area under the lipid peak to the area under the water peak were statistically significant among the groups. Specifically, as the severity of fatty liver increased, the value of each index increased correspondingly. In the pairwise comparisons, the mean lipid peak, area under the lipid peak, ratio of the lipid peak to the water peak, and ratio of the area under the lipid peak to the area under the water peak were significantly different between the no fatty liver and moderate fatty liver groups, whereas no differences were noted between the severe fatty liver group and the mild or moderate fatty liver group. Area under the ROC curve (AUC) of area ratio in lipid and water and ratio in lipid and water in the no fatty liver group to mild fatty liver group, mild fatty liver group to moderate fatty liver group, and moderate fatty liver disease group to severe fatty liver group, were 0.705, 0.900, and 0.975, respectively. CONCLUSION: (1)H MRS is a noninvasive technique that can be used to provide information on the effect of liver steatosis on hepatic metabolic processes. This study indicates that the (1)H MRS can be used as an indicator of steatosis in patients with chronic hepatitis C.

3.0T 31P MR spectroscopy in assessment of response to antiviral therapy for chronic hepatitis C.

AIM: To investigate the utility of phosphorus-31 (31P) magnetic resonance spectroscopy (MRS) as a noninvasive test for assessment of response to interferon and ribavirin treatment in patients with different severities of hepatitis C virus infection. METHODS: Sixty chronic hepatitis C patients undergoing antiviral therapy with interferon and ribavirin underwent 31P MRS at 3.0T before treatment, 6 mo after the start of treatment, and 1 year after the start of treatment. RESULTS: The phosphomonoester (PME)/phosphodiester (PDE) ratio at 6 mo after the start of antiviral therapy in the Child-Pugh B and C groups were significantly higher than those before therapy, but this was not seen in the Child-Pugh A group. In the antiviral therapy group, the PME/PDE ratios had decreased on follow-up MR spectroscopy. However, in the virological nonresponder group, the PME/PDE ratios on follow-up imaging were similar to the baseline values. CONCLUSION: 31P MRS can be used to provide biochemical information on hepatic metabolic processes. This study indicates that the PME/PDE ratio can be used as an indicator of response to antiviral treatment in chronic hepatitis C patients.

[Predictive value of tumor vessel density from enhanced spiral CT scan for lymph node and distant metastasis of colorectal cancer].

OBJECTIVE: To test whether the tumor vessel density (TVD) from the enhanced spiral CT can preoperatively predict nodal status and distant metastasis of colorectal cancer. METHODS: Forty cases of colorectal cancer patients who received surgical treatment were included in this study. The three dimensional tumor vessels were reconstructed by an enhanced CT 64-slice spiral CT and its AW4.4 image processing platform. The TVD was measured by the 1000 high-resolution color graphics pathological analysis system. The TVD level was compared between different tumor size, classification, and TNM stage. The postoperative pathological staging was taken as golden standard. RESULTS: The sensitivity, specificity and accuracy for direct prediction of lymph node metastasis by the enhanced CT 64-slice spiral CT was 74.1%(20/27), 53.8%(7/13) and 67.5%(27/40) respectively. The TVD from the reconstructed three dimensional tumor vessels in the group with lymph node metastasis was significantly higher than that without metastasis(0.070±0.046 vs. 0.037±0.013, P<0.05). The TVD in the distant metastasis group was significantly higher than that without distant metastasis (0.130±0.032 vs. 0.049±0.030, P<0.01). No difference of TVD was found between different tumor size, invasion depth, and differentiation type. CONCLUSION: TVD level from the reconstructed three dimensional tumor vessels can indicate lymph node and distant metastasis of colorectal cancer.

Critical influenza (H1N1) pneumonia: imaging manifestations and histopathological findings.

BACKGROUND: The global outbreak of influenza A (H1N1) has led to the Ministry of Health of China listing it as one of the A-class infectious diseases. Pneumonia is the most serious complication of influenza A, commonly causing death. Populations are ordinarily susceptible to influenza A. This study aimed to investigate the imaging manifestation features of critical influenza A (H1N1) pneumonia and to improve its diagnostic techniques. METHODS: A total of seven death cases from critical influenza A (H1N1) pneumonia were retrospectively analyzed on their imaging manifestations and autopsy data. Pulmonary CT scanning was performed for five cases, with one receiving additional chest X-ray and chest CT scanning, and chest postero-anterior position X-ray examination was performed for other two. Autopsy was performed for five cases and postmortem examinations were performed for other two cases. RESULTS: The seven cases of influenza A showed critical manifestations in 4 - 7 days after symptoms onset, with two having basic diseases of diabetes and one being pregnant. Extensive blurry high-density shadows of bilateral lungs were found in three cases, which were most obvious in middle and inferior parts of lungs. Pulmonary CT scanning revealed bilateral flaky parenchymal shadows in peripheral, dorsal and fundus segments of the middle-inferior parts of lungs, with one case of complicated pneumothorax, atelectasis and pleural effusion and another case of thin-walled cavity and dilated bronchi shadows in the superior parts of lungs. CONCLUSIONS: Diagnostic imaging is an important assessing tool for critical influenza A (H1N1) pneumonia. The imaging manifestations are characteristic instead of being specific. The definitive diagnosis can be made in combination with clinical examinations and laboratory tests.

The differences in imaging features of malignant and benign branch duct type of Intraductal Papillary Mucinous Tumor.

OBJECTIVE: To investigate the difference in the radiological features of malignant and benign branch duct type of IPMT (Intraductal Papillary Mucinous Tumor) of the pancreas. METHODS: Thirty-six patients who were referred for operation with branch duct type of IPMT of the pancreas were included in this study. All cases underwent both CT and MRI with contrast enhancement. The size of the cystic lesions, the presence and size of mural nodules, and the amount of dilatation of the MPD were assessed by two independent radiologists, and the results were compared with pathological findings. RESULTS: Histological examination revealed adenoma in 8 cases, AH (atypical hyperplasia) in 8 cases, CIS (carcinoma in situ) in 8 cases and invasive carcinoma in 12 cases. Patients of the malignant group were older than those in the benign group (mean age: 67 yrs vs 60 yrs, respectively), but no statistically significant (p=0.05). Males (16/4 vs 10/6) more often complained weight loss and jaundice. The malignant tumor was more frequently located in the head-body and body. Compared with the benign group, the mean sizes of the cyst, mural nodules, MPD of the malignant group were 44 mm, 13 mm, 7.5 mm and benign group were 31 mm, 5 mm, 3.5 mm respectively. All these difference are statistically significant (p<0.05). In 4 cases of the 20 in the malignant group, soft tissue suggesting spread of disease into the adjacent viscera and peritoneum was detected. CONCLUSION: Cyst size over 30 mm and mural nodule over 8 mm, irregular thick septa, dilatation of the MPD, and accompany with soft tissue mass may be helpful factors in determining malignancy.

Colonic polyps: application value of computer-aided detection in computed tomographic colonography.

BACKGROUND: Colonic polyps are frequently encountered in clinics. Computed tomographic colonography (CTC), as a painless and quick detection, has high values in clinics. In this study, we evaluated the application value of computer-aided detection (CAD) in CTC detection of colonic polyps in the Chinese population. METHODS: CTC was performed with a GE 64-row multidetector computed tomography (MDCT) scanner. Data of 50 CTC patients (39 patients positive for at least one polyp of ≥ 0.5 cm in size and the other 11 patients negative by endoscopic detection) were retrospectively reviewed first without computer-aided detection (CAD) and then with CAD by four radiologists (two were experienced and another two inexperienced) blinded to colonoscopy findings. The sensitivity, specificity, positive predictive value, negative predictive value, and accuracy of detected colonic polyps, as well as the areas under the ROC curves (Az value) with and without CAD were calculated. RESULTS: CAD increased the overall sensitivity, specificity, positive predictive value, negative predictive value and accuracy of the colonic polyps detected by experienced and inexperienced readers. The sensitivity in detecting small polyps (5 - 9 mm) with CAD in experienced and inexperienced readers increased from 82% and 44% to 93% and 82%, respectively (P > 0.05 and P < 0.001). With the use of CAD, the overall false positive rate and false negative rate for the detection of polyps by experienced and inexperienced readers decreased in different degrees. Among 13 sessile polyps not detected by CAD, two were ≥ 1.0 cm, eleven were 5 - 9 mm in diameter, and nine were flat-shaped lesions. CONCLUSIONS: The application of CAD in combination with CTC can increase the ability to detect colonic polyps, particularly for inexperienced readers. However, CAD is of limited value for the detection of flat polyps.