Mikiko Miyasaka

Utility of spinal MRI in children with anorectal malformation

BackgroundThe association between spinal cord anomalies and imperforate anus is well recognized. Until now, the incidence of tethered cord has been assumed to be higher in patients with high-type imperforate anus. However, recent reports suggest that tethered cord is as common in patients with a low lesion as in those with a high lesion.ObjectiveTo review the incidence of spinal cord anomalies in those with a low lesion and those with a high (including intermediate) anorectal malformation (ARM), and to determine the best diagnostic imaging strategy.Materials and methodsA group of 50 consecutive patients with postoperative ARM and in whom spinal MRI had been performed were identified retrospectively. We reviewed and compared the following factors between those with a high lesion and those with a low lesion: (1) clinical symptoms, (2) spinal cord anomalies, and (3) vertebral anomalies.ResultsThe incidence of spinal cord anomalies was no different between those with a high lesion and those with a low lesion, and spinal cord anomalies were present regardless of the presence of vertebral anomalies or symptoms.ConclusionOwing to the high incidence of spinal cord anomalies in patients with imperforate anus, MRI is the best imaging tool for detecting such anomalies regardless of the level of the lesion.

The degree of spleen stiffness measured on acoustic radiation force impulse elastography predicts the severity of portal hypertension in patients with biliary atresia after portoenterostomy

BACKGROUND/PURPOSE Acoustic radiation focus impulse (ARFI) elastography is a new method for assessing the degree of tissue stiffness. We herein evaluated the degree of spleen stiffness (SS) using ARFI elastography in patients with biliary atresia (BA) after Kasai portoenterostomy (KPE). METHODS We retrospectively collected the liver stiffness (LS) and SS values on ARFI elastography from 43 patients undergoing KPE between September 2010 and November 2013. We analyzed the correlations between these values and variables related to the severity of liver dysfunction and portal hypertension (PHT). The data were expressed as the standard deviation score (z-score) relative to the previously reported normal values for the patients age. RESULTS The SS value was significantly associated with the spleen diameter and development of collateral vessels, in comparison to the LS value. Interestingly, there was a significant correlation between SS value and the portal vein (PV) diameter. Thirty patients (69.8%) consequently underwent LT; these patients showed higher SS values and smaller PV diameters than the patients monitored without LT. CONCLUSIONS The degree of SS measured on ARFI elastography can be used to predict the severity of PHT in BA patients after KPE.

Living donor liver transplantation for multiple intrahepatic portosystemic shunts after involution of infantile hepatic hemangiomas.

We describe a 6-year-old girl presenting with multiple intrahepatic portosystemic shunts after the involution of infantile hepatic hemangiomas (IHHs), who successfully underwent living donor liver transplantation. The chronological changes of radiologic findings indicated that remnant portovenous shunts at the time of IHHs involution developed gradually on the background of atrophic intrahepatic portal veins. This suggests that patients should be carefully followed up for the late onset of intrahepatic portosystemic shunts after the involution of IHHs.

Estimation of adaptive computed tomography dose index based on body weight in pediatric patients

PurposeThe aim of this study was to create an adaptive computed tomography dose index (by volume) (CTDIvol) for pediatric patients that would be fitted to a patient’s particular body weight and to compare the adaptive CTDIvol with the CTDIvol displayed on the screen of the CT console.Materials and methodsCT images of 60 children whose body weights were known were available for calculating the total amount of modified CT numbers as an attenuation area. The attenuation area values of four differentsized acryl phantoms were also calculated. The dose measurements of all four phantoms were carried out. We combined the results of the abdominal CT and phantom experiments. The weight-based complementary ratio for adaptive CTDIvol was calculated, and the result was applied to an example of pediatric abdominal CT protocol.ResultsThe adaptive CTDIvol was always larger than the displayed CTDIvol with both small and large fields of view (FOV). The adaptive CTDIvol was 2.2 times larger than the displayed CTDIvol in the maximum value with the large FOV and 1.2 times larger with the small FOV.ConclusionWe radiologists must be the child’s advocate and protect children from the deleterious effects of any of our technologies, including a lower indication of CTDIvol on the screen of a CT console.

Ultrasound in pediatric patients with suspected acute appendicitis: Value in establishing alternative diagnoses

The objective of this study was to investigate the value of ultrasound to establish alternative diagnoses in pediatric patients with clinical suspicion of acute appendicitis. A total of 206 consecutive patients with right lower abdominal pain were evaluated by ultrasound. For each case, the sonographic findings documented on the report at the time of examination were compared with the final diagnosis.Our results demonstrated that ultrasound was 94% accurate in the diagnosis of acute appendicitis. Among all 42 of the 108 truenegative cases of appendicitis, there was a variety of sonographic findings other than appendiceal abnormality, comprising intestinal and/or mesenteric, gallbladder, and ovarian abnormalities. Sonographic findings were well correlated with clinical and/or surgical diagnoses. Only 3 of these 42 cases were treated by surgical intervention.Ultrasound of pediatric right lower abdominal pain is a reliable diagnostic tool not only for appendicitis but for alternative diagnoses mimicking appendicitis.

Prenatally diagnosed, right-sided congenital diaphragmatic hernia complicated by hepatic pulmonary fusion and intrathoracic kidney

Right-sided, congenital diaphragmatic hernia is not common but accounts for about 20% of all congenital diaphragmatic hernia. It sometimes has serious complications, such as intrathoracic kidney and hepatic pulmonary fusion. Here we report a rare case of right-sided diaphragmatic hernia, complicated by intrathoracic kidney and hepatic pulmonary fusion. Repair of the diaphragm via the abdominal approach was difficult and the disease recurred. The second operation was through a right thoracotomy and was successful. The biopsied specimen of the diaphragm contained hepatocytes and bile duct cells which strongly suggested the close relationship between liver and the diaphragm in this case. Right-sided, congenital diaphragmatic hernia (R-CDH) is rare compared to left-sided CDH and accounts for about 20% of the disease. R-CDH is sometimes difficult to diagnose prenatally and Duess et al. reported that prenatal diagnosis and patch closure may be risk factors for increased mortality. Furthermore, R-CDH may be complicated by some specific pathophysiological states, such as intrathoracic kidney and hepatic pulmonary fusion, which is rare but causes complicated and difficult problems for the surgical repair of the diaphragm. In this report, we describe a rare case with the combination of intrathoracic kidney and hepatic pulmonary fusion in R-CDH and discuss the etiology of the disease and surgical treatment. Correspondence to: Yutaka Kanamori, Division of Surgery, Department of Surgical Specialties, National Center for Child Health and Development, Tokyo, Jap2-10-1 Okura, Setagaya, Tokyo 157-8535, Japan, Tel; +81-3-3416-0181, Fax; +81-3-3416-2222; E-mail: kanamori-y@ncchd.go.jp.

Donor double common bile duct in living donor liver transplantation.

Dear Sirs, We read with interest the recent article by Iwasaki et al. [1] focusing on the safety in living donor liver transplantation (LDLT). We confronted a living donor case of double common bile duct (DCBD), an extremely rare congenital anomaly which could involve surgical pitfalls that could lead to serious injuries of the bile duct and make biliary reconstruction more complicated in LDLT, especially in the recovering of the right liver lobe [2,3]. We thus had better reconsider the importance of obtaining precise information about the biliary anatomy during LDLT. The living donor was a 47-year-old female without any significant medical history. A standard living donor left lateral hepatectomy was performed. Three sessions of intraoperative cholangiography (IOC) with C-arm were performed routinely, including before the hilar dissection with a clip placed on the proposed site of the biliary transection, before the division of the bile duct and after the hepatectomy. Real-time IOC with C-arm in the first session revealed the DCBD draining the same portion of the duodenum (Fig. 1a). As this bile duct anomaly did not influence the recovering of the left lateral segment (LLS) graft, the division of left bile duct was performed after the confirming IOC in the second session. The final IOC was performed after obtaining the LLS, and no injury of remnant bile duct was confirmed (Fig. 1b). A careful review of the preoperative computed tomography revealed three ducts in line, including the cystic duct, and the right and left common bile ducts (Fig. 1c). Choi et al. [3] proposed a morphological classification system of DCBD. According to the report, our case was classified as a type Vb anomaly. Only two cases of this type have been reported [3,4]. In right lobe LDLT, there might be two ways of performing biliary resection after dividing the intrahepatic communicating channel: with or without resection of right common bile duct. In both methods, it is crucial to avoid making a graft with two or more ducts, as the presence of multiple ducts can be a significant risk factor for the development of biliary complications. To ensure the safety of the donor, preoperative evaluations and careful intraoperative techniques are needed, especially with regard to the biliary anatomy. Regarding the biliary anatomy, real-time IOC with C-arm is still a paramount imaging technique, as it provides precise information [5]. In our centre, the preoperative imaging of the biliary anatomy is not routinely performed for potential donor candidates because of the