title: Comparative analysis of spherical and fusiform choledochal cyst based on three-dimensional magnetic resonance cholangiopancreatography, biliary amylase, and histopathological examination.
abstract: OBJECTIVE
  The aim was to compare biliary amylase, common channel, and gall bladder/liver histopathology between spherical and fusiform choledochal cysts.
  
  
  METHODS
  Children undergoing cyst excision with Roux-en-Y hepatico-jejunostomy over a 17 months period were prospectively studied. The common channel was assessed by three-dimensional (3D) magnetic resonance cholangiopancreatography (MRCP).
  
  
  RESULTS
  Among 22 patients (spherical = 10, fusiform = 12), there was a higher incidence of spherical cysts in infants (5/7-71.4%) and fusiform cysts in older children (10/15-66.7%) (P = 0.09). Common channel identified in 14 (64%) cases was long (>10 mm) in 5 (38.2%) (one spherical, four fusiform [P = 0.5]) with associated high biliary amylase levels (>500 IU/L) in four (one spherical, three fusiform) (P = 0.05). Exact point of junction of common bile duct with pancreatic duct was visible with coronal half-Fourier-acquisition single-shot turbo spin-echo and 3D sampling perfection with application with optimize contrast using different flip angle evolution sequence using a reformatted plane of axis, particularly coronal, and coronal oblique orientation. Biliary amylase was raised (>100 IU/L) in 4 (40%) in the spherical group, compared to 8 (67%) in the fusiform group. Mean biliary amylase was similar in gallbladder and cyst in spherical but higher in gallbladder in fusiform cysts. Mean biliary amylase was <500 IU/L in 85.7% infants. Five out of 7 infants had liver fibrosis or cirrhosis on histopathology (P = 0.05). There were no dysplastic changes in the gallbladder epithelium.
  
  
  CONCLUSIONS
  Three-dimensional MRCP delineated the common channel in two-third cases especially in coronal and coronal oblique orientation. The long common channel may have an etiological role in fusiform cysts. Spherical cysts, especially in infants, have a higher incidence of obstructive cholangiopathy.
authors.affiliation: Department of Pediatric Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Neel
authors.initials: N
authors.lastname: Aggerwal
authors.affiliation: Department of Pediatric Surgery, Advanced Pediatric Centre, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Prema
authors.initials: P
authors.lastname: Menon
authors.affiliation: Department of Pediatric Surgery, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Katragadda Lakshmi Narasimha
authors.initials: KL
authors.lastname: Rao
authors.affiliation: Department of Radiodiagnosis, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Kushaljit S
authors.initials: KS
authors.lastname: Sodhi
authors.affiliation: Department of Histopathology, Postgraduate Institute of Medical Education and Research, Chandigarh, India.
authors.forename: Nandita
authors.initials: N
authors.lastname: Kakkar
keywords: Biliary amylase; choledochal cyst; common channel; fusiform; spherical; three-dimensional magnetic resonance cholangiopancreatography