Kazuchika Hagiwara

Pancreas divisum as a predisposing factor for chronic and recurrent idiopathic pancreatitis: initial in vivo survey

Background It is a controversial issue whether pancreas divisum (PD) induces pancreatitis. All previous studies have investigated this issue based on endoscopic procedures, which inevitably involve a selection bias. Objectives To determine the unbiased prevalence rate of PD in a community population and to investigate the effect of PD on idiopathic pancreatitis using a non-invasive magnetic resonance (MR) technique. Design Cross-sectional study. Patients The study enrolled 504 subjects from the community who participated in the medical check-up programme and 46 patients with idiopathic pancreatitis (8 acute, 23 chronic, 15 recurrent) extracted from 70 122 consecutive MR studies performed at an academic tertiary care hospital. Interventions All subjects underwent magnetic resonance (MR) scanning and medical examination. Main outcome measures Statistical comparison between subjects from the community and patients with idiopathic pancreatitis was made for the rate of PD (and its subtypes: classical PD, PD with absent ventral duct, and incomplete PD), MR findings, and clinical features. Results Multiple logistic regression analysis revealed PD as a significant factor that induces pancreatitis (OR 23.4; p<0.0001). The PD rate was significantly higher for all/chronic/recurrent idiopathic pancreatitis patients (35%/43%/33%; p<0.001 for all) than for subjects in the community group (2.6%), but was not higher for acute pancreatitis (13%; p=0.357). All PD subtypes were indicated to induce idiopathic pancreatitis but showed different associations with each onset type of pancreatitis. Conclusions This is the first study to describe the prevalence of PD and PD subtypes in a community population and their association with idiopathic pancreatitis in vivo based on the findings of non-invasive MR and with minimal selection bias. It is concluded that PD should be considered a predisposing factor for chronic and recurrent pancreatitis.

Intravascular gas distribution in the upper abdomen of non-traumatic in-hospital death cases on postmortem computed tomography.

OBJECTIVES To investigate the occurrence of intravascular gas in the liver, kidneys, spleen, and pancreas by postmortem computed tomography (PMCT) in cases of non-traumatic in-hospital deaths and elucidate the relationship between the PMCT data and clinical information or autopsy results. METHODS The study included 45 cadavers of patients who died while receiving treatment in our academic tertiary-care hospital between April and December 2009. All subjects underwent PMCT and conventional autopsy. The appearance of postmortem gas in the liver, kidney, spleen, and pancreas was assessed using PMCT and scored using a subjective scale (liver, L0-L3; kidney, K0-K2; spleen, S0-S1; and pancreas, P0-P1), and the distribution of gases in the vessels of the liver (arteries, veins, and portal veins) was analyzed. The relationship between the gas score and time elapsed since death, cardiopulmonary resuscitation (CPR), administration of antibiotics, a history of bacteremia, or cause of death was assessed statistically. RESULTS Positive correlations were found between administration of CPR and liver and kidney gas scores (P=0.008 and 0.002, respectively), but not with spleen and pancreas gas (P=0.291 and 0.535, respectively). No significant relationship between distribution of gas in the vessels of the liver and CPR was found. No other significant correlations between gas and any of the other parameters described above were found. While significant correlations were detected in no-CPR cases between liver gas, kidney gas, spleen gas, and pancreas gas (P<0.001 for all six combinations), no correlation between these parameters was detected in the CPR cases. CONCLUSIONS The present study was the first statistical analysis of intravascular gas in the liver, kidneys, spleen, and pancreas by using PMCT in non-traumatic in-hospital death cases. The results showed that PMCT in the presence and absence of CPR reveals differences in intraorgan gas distribution. In addition, the detection of intraorgan gas on PMCT cannot be used to predict time elapsed since death, and it is not affected by the administration of antibiotics, a history of bacteremia, and cause of death. Awareness of these postmortem changes is important for the accurate interpretation of PMCT results.

Retroportal main pancreatic duct with circumportal pancreas: radiographic visualization.

PURPOSE The aim of this study was to investigate the imaging findings of retroportal main pancreatic duct (RMPD), a rare anomaly of the pancreas, and circumportal pancreas (CP) on computed tomography (CT) and magnetic resonance (MR) imaging. We also reviewed the previous literature and discussed its best imaging method, etiology and clinical importance. METHODS This work is a retrospective study. Two cases of RMPD were enrolled. The imaging findings of RMPD and CP were reviewed among the various CT and MR images obtained. Differences in visualization among the scans were evaluated using a four-stage model. RESULTS RMPD was always accompanied by CP. RMPD was detectable on contrast-enhanced CT but not on noncontrasted CT. RMPD was shown most clearly on arterial, portal and late phases of contrast-enhanced CT, contrast-enhanced fat-suppressed T1-weighted images and fat-suppressed T2-weighted images. CP was much easier to detect than RMPD and could be identified even on noncontrasted images. CONCLUSIONS We described the fourth and the fifth reported cases of RMPD. This is the first study to describe its MR imaging findings. CP was always present in cases of RMPD and was easily detectable on tomographic images. When radiologists or surgeons notice CP, it is necessary to pay attention to the course of the main pancreatic duct, particularly preoperatively to avoid surgical complications. It should be noted that these anomalies are undetectable on projection images.

Hypostasis in the heart and great vessels of non-traumatic in-hospital death cases on postmortem computed tomography: Relationship to antemortem blood tests

OBJECTIVES The purpose of this study was to investigate hypostasis in the heart and great vessels (HHGV) by postmortem computed tomography (PMCT) in cases of non-traumatic in-hospital deaths and to analyze relationships between clarity of HHGV and antemortem blood markers. MATERIAL AND METHODS The study included 31 cadavers of patients who died while receiving treatment in our academic tertiary-care hospital between April and December 2009. Antemortem blood tests including both hematological and blood coagulation markers were performed within 48h before death, and PMCT and conventional autopsies were performed. The findings of HHGV were assessed in the following six locations: the superior vena cava, right atrium, right ventricle, thoracic aorta, left atrium, and left ventricle. The clarity of HHGV on PMCT was divided into two groups using attenuation of the left ventricular wall as a reference: no/obscure HHGV group and clear HHGV group. The relationships between clarity of HHGV and six blood markers [red blood cell (RBC) count, hemoglobin (Hb), hematocrit (Ht), prothrombin percentage activity (PT%), activated partial thromboplastin time (aPTT), and fibrinogen] were evaluated statistically. RESULTS We observed no/obscure HHGV in 14 patients (45%) and clear HHGV in 17 patients (55%). The level of fibrinogen in clear HHGV group was significantly higher than in no/obscure HHGV group (P=0.029). No relationships were found between clarity of HHGV and other five blood markers. CONCLUSION HHGV is a common PMCT finding. Clear HHGV on PMCT was related to higher level of fibrinogen in non-traumatic in-hospital death cases.

Postmortem changes of the thyroid on computed tomography

OBJECTIVE To evaluate the radiographic features of the thyroid on postmortem computed tomography (PMCT). METHODS We studied the bodies of 32 subjects who had been treated and subsequently died in our tertiary care hospital between April and December 2009. The thyroids were imaged by antemortem computed tomography (AMCT), PMCT, and examined by conventional autopsy. Differences between the radiographic features of the thyroid on AMCT and PMCT, and time since AMCT were evaluated statistically. RESULTS CT values of the thyroid decreased after death with an average of 114.2 Hounsfield Units (HUs) on AMCT vs. 107.7HU on PMCT (paired t-test, P=0.023). There was no correlation between the elapsed time from AMCT and differences of CT values of the thyroid on AMCT and PMCT (Spearmans rank correlation test, P>0.05). CONCLUSION We showed that CT values of the thyroid decreased after death.

Meandering Main Pancreatic Duct as a Relevant Factor to the Onset of Idiopathic Recurrent Acute Pancreatitis

Background Meandering main pancreatic duct (MMPD), which comprises loop type and reverse-Z type main pancreatic duct (MPD), has long been discussed its relation to pancreatitis. However, no previous study has investigated its clinical significance. We aimed to determine the non-biased prevalence and the effect of MMPD on idiopathic pancreatitis using non-invasive magnetic resonance (MR) technique. Methods and Findings A cross-sectional study performed in a tertiary referral center. The study enrolled 504 subjects from the community and 30 patients with idiopathic pancreatitis (7 acute, 13 chronic, and 10 recurrent acute). All subjects underwent MR scanning and medical examination. MMPD was diagnosed when the MPD in the head of pancreas formed two or more extrema in the horizontal direction on coronal images of MR cholangiopancreatography, making a loop or a reverse-Z shaped hairpin curves and not accompanied by other pancreatic ductal anomaly. Statistical comparison was made among groups on the rate of MMPD including loop and reverse-Z subtypes, MR findings, and clinical features. The rate of MMPD was significantly higher for all idiopathic pancreatitis/idiopathic recurrent acute pancreatitis (RAP) (20%/40%; P<0.001/0.0001; odds ratio (OR), 11.1/29.0) than in the community (2.2%) but was not higher for acute/chronic pancreatitis (14%/8%; P = 0.154/0.266). Multiple logistic regression analysis revealed MMPD to be a significant factor that induces pancreatitis/RAP (P<0.0001/0.0001; OR, 4.01/26.2). Loop/reverse-Z subtypes were found more frequently in idiopathic RAP subgroup (20%/20%; P = 0.009/0.007; OR, 20.2/24.2) than in the community (1.2%/1.0%). The other clinical and radiographic features were shown not associated with the onset of pancreatitis. Conclusions MMPD is a common anatomical variant and might be a relevant factor to the onset of idiopathic RAP.

Fluid in the airway of nontraumatic death on postmortem computed tomography: relationship with pleural effusion and postmortem elapsed time.

AbstractTo evaluate radiographic features of endotracheal/endobronchial fluid in the airway (FA) observed on postmortem computed tomography (PMCT). We studied 164 subjects who died at our hospital between April 2009 and September 2012. Fluid in the airway was considered positive when fluid was identified in the lumen of 1 of the 2 main bronchi in continuity with a segmental bronchus. Pleural effusion and atelectasis/consolidation of the lung lower lobes were also evaluated. Fluid in the airway was observed in 60 (71%) of 84 subjects with unilateral or bilateral pleural effusion, and in 44 (55%) of 80 subjects without pleural effusion (P = 0.029). Of the latter, 41 (93%) had atelectasis/consolidation of the lower lung lobes. Among subjects without pleural effusion, average times after death to PMCT of subjects with and without FA were 501 and 314 minutes, respectively (P = 0.01). Time-course analysis showed that cases with FA on PMCT largely correlated with time after death (R2 = 0.7966). Fluid in the airway is frequently observed on PMCT in subjects with pleural effusion or atelectasis/consolidation of the lung. No FA in subjects without pleural effusion correlated to shorter times after death. In addition, FA frequency on PMCT increased over time after death.

Visualization of Bile Movement Using MRI Spin-Labeling Technique: Preliminary Results

OBJECTIVE The purpose of this article is to noninvasively visualize intrabiliary bile movement using an MRI spin-labeling technique and administration of water, full-fat milk, and negative contrast agent as stimuli for bile excretion. SUBJECTS AND METHODS Six healthy volunteers underwent three studies with each of three oral liquid agents (water, full-fat milk, and manganese chloride solution) for a total of 18 MRI studies. Oblique-coronal T2-weighted images of the common bile duct were acquired at an inversion time of 1500 milliseconds after pulse labeling using a spin-labeling technique with an inversion pulse, repeated at intervals of 22 seconds. Bile flow rate was measured before and for 50 minutes after administration of the oral liquid agents, and its correlation with the change in gallbladder volume was assessed. RESULTS Both anterograde and retrograde intermittent bile movements were successfully visualized in the common bile duct. The summation of excreted bile volume calculated from spin-labeled images correlated significantly with a decrease in gallbladder volume (p = 0.011). Milk stimulated significantly prolonged bile flow; flow was momentary with manganese chloride and mild with water; however, gallbladder volume decreased only in milk studies (p = 0.003). Biliary flow early after oral intake correlated significantly with gallbladder contractility at 50 minutes after oral intake (p = 0.049). CONCLUSION A new method for visualizing intrabiliary bile movement in semi-real time (22-second time resolution) using an MRI spin-labeling technique was proposed. Bile was shown to be excreted in a to-and-fro type of movement. Administration of water and negative contrast agent may induce temporary bile excretion.