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Publications (4)6.71 Total impact

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    ABSTRACT: The triangular cord sign (TCS) is a specific ultrasonographic finding, reflecting a fibrotic mass at the porta hepatis in biliary atresia (BA). We evaluated whether BA can be diagnosed by ultrasonography alone using 3 findings: TCS, gallbladder length (GBL), and gallbladder contractility (GBC). Subjects comprised 85 infants (median age, 47 days; range, 4-144 days) with cholestatic jaundice who underwent ultrasonographic examination for diagnosis between May 1996 and June 2006. Medical records were reviewed with regard to TCS, GBL, and GBC. Positive findings for BA included TCS >or=3 mm, GBL <15 mm, and GBC <68% (for < 12 weeks) or <25% (for >or=12 weeks). Biliary atresia was diagnosed in 48 patients surgically, with other cholestatic diseases diagnosed in the remaining 37 patients. Triangular cord sign was positive in 41 of 48 infants with BA and negative in 35 of 37 infants without BA. The 7 patients with BA who displayed negative results for TCS displayed positive findings for GBL or GBC. Positive predictive value in the diagnosis of BA was 98% if positive TCS was combined with abnormal gallbladder findings, whereas negative predictive value in diagnosis of BA was 100% if negative TCS was combined with findings of a normal gallbladder. Biliary atresia can be accurately diagnosed by ultrasonography using the findings of TCS combined with GBL and GBC.
    Journal of Pediatric Surgery 12/2007; 42(12):2093-6. · 1.38 Impact Factor
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    ABSTRACT: The aim of this study was to determine the etiology and appropriate surgical treatment for acquired tracheal stenosis that developed in patients who had undergone prolonged endotracheal mechanical ventilation as premature neonates. During the period 2000-2004, four patients aged 1-16 years were referred for tracheal stenosis characterized by stridor, choking, and recurrent pulmonary infection. All patients had undergone endotracheal mechanical ventilation for 2-5 months for respiratory distress related to prematurity (gestational age 25-29 weeks, birth weight 648-1,222 g). During this period, methicillin-resistant Staphylococcus aureus was predominantly cultured from the trachea. All patients exhibited a stenotic lesion encompassing 30-37% of the entire tracheal length on spiral CT. On palpation and inspection of the trachea during surgery, however, the stenotic segment appeared to encompass over 50% of the entire trachea. The carina was intact. Three patients underwent slide tracheoplasty with a tracheal resection and the other underwent resection and end-to-end anastomosis. Of the three patients treated by slide tracheoplasty, two are currently free of respiratory symptoms. However, one patient in this group required secondary resection of the remaining stenotic lesion with end-to-end anastomosis. This patient is currently asymptomatic. The remaining patient who underwent a resection and end-to-end anastomosis is doing well. The resected specimen showed fibrosis and degeneration of tracheal cartilage. A combination of prematurity, prolonged endotracheal mechanical ventilation and tracheal infection seem to be responsible for tracheal inflammation and stenosis. When considering surgical procedures for acquired tracheal stenosis, resection and end-to-end anastomosis are desirable. However, slide tracheoplasty with a partial tracheal resection is indicated for the treatment of stenosis involving a long tracheal segment.
    Pediatric Surgery International 12/2006; 22(11):887-90. · 1.22 Impact Factor
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    ABSTRACT: A total of four patients with communicating bronchopulmonary foregut malformation were treated surgically at Kobe Children's Hospital between 1993 and 2004. Of these, three patients displayed congenital tracheobronchial stenosis and developed life-threatening respiratory distress soon after birth. In each case, anomalous bronchi arose from the lower portion of the esophagus and connected to the lower part of the ipsilateral lung. This anomaly involved the right lung in two patients, and the left lung in one patient. Tracheobronchial stenosis extended from the inlet of the thorax to the carina in one patient, and to the contralateral main stem bronchus in two patients. Surgical treatment included division of the esophageal bronchus and anastomosis of bronchus to the trachea in one patient. In the other patient, the ipsilateral lung was resected and the stenotic tracheobronchus was stented. The remaining patient underwent pneumonectomy of the ipsilateral lung. Details of this fatal anomaly and a discussion of appropriate surgical management are described herein.
    Pediatric Surgery International 12/2005; 21(11):932-5. · 1.22 Impact Factor
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    ABSTRACT: A retrospective review was performed to evaluate the importance of the "triangular cord" sign in comparison with gallbladder length and contraction for the diagnosis of biliary atresia in pediatric patients. Fifty-five fasting infants with cholestatic jaundice were examined on sonography. The examinations focused on the visualization of the triangular cord sign and assessment of gallbladder length and contraction. The diagnosis of neonatal hepatitis or of other causes of infantile cholestasis was made if symptom resolution occurred during follow-up. A triangular cord sign was found in 27 of 29 infants with biliary atresia and in one of 26 infants with neonatal hepatitis or other causes of infantile cholestasis. The diagnostic accuracy was 95%, sensitivity was 93%, and specificity was 96%. The gallbladder was thought to be abnormal if it was less than 1.5 cm long, was not detectable, or was detectable but had no lumen. The gallbladder was abnormal in 21 of 29 infants with biliary atresia, whereas it was abnormal in eight of 26 infants with neonatal hepatitis or other causes of infantile cholestasis. The diagnostic accuracy was 71%, sensitivity was 72%, and specificity was 69%. The gallbladder was detectable on sonography in 13 infants with biliary atresia and 26 infants with neonatal hepatitis or other causes of infantile cholestasis. Gallbladder contraction was not confirmed in 11 of 13 infants with biliary atresia and seven of 26 infants with neonatal hepatitis or other causes of infantile cholestasis. The diagnostic accuracy was 77%, sensitivity was 85%, and specificity was 73%. The triangular cord sign was a more useful sonographic finding for diagnosing biliary atresia than gallbladder length and contraction.
    American Journal of Roentgenology 12/2003; 181(5):1387-90. · 2.90 Impact Factor