title: Ultra-high-resolution MR imaging of esophageal carcinoma at ultra-high field strength (7.0T) ex vivo: correlation with histopathologic findings.
abstract: OBJECTIVE
  To determine the usefulness of ultra-high-resolution magnetic resonance (MR) imaging at an ultra-high field strength (7.0T), using a voxel volume of 9.5-14nL, as means of evaluating the depth of mural invasion by esophageal carcinomas.
  
  
  METHODS
  Twenty esophageal specimens containing 20 carcinomas were studied using a 7.0-T MR imaging system with a four-channel surface coil. Ultra-high-resolution MR images were obtained with a field of view of 50-60mm×25-30mm, a matrix of 512×256, and a section thickness of 1.0mm, resulting in a voxel volume of 0.0095-0.014mm(3) (9.5-14nL). Differences between tumor tissue and the esophageal wall layers and between tumor tissue and fibrosis were evaluated using visual signal intensity scoring measurements. MR images were then compared with histopathologic findings as the reference standard.
  
  
  RESULTS
  Ultra-high-resolution T2-weighted MR images at 7.0T clearly depicted the normal esophageal wall in all 20 specimens (100%) as consisting of eight layers, which clearly corresponded to the tissue layers of the esophageal wall. Ultra-high-resolution T2-weighted MR images made it possible to differentiate between the tumor tissue and fibrosis clearly (P<0.01). In all 20 esophageal carcinomas (100%), ultra-high-resolution T2-weighted MR images made it possible to determine the depth of tumor invasion in the esophageal wall as observed in the histopathologic sections. Regional lymph node involvement was also clearly depicted in four specimens.
  
  
  CONCLUSIONS
  Ultra-high-resolution 7.0-T MR imaging, using a voxel volume of 9.5-14nL, provides clear delineation of the esophageal wall layers, clear differentiation of tumor tissue from fibrosis, and excellent diagnostic accuracy for evaluating mural invasion by esophageal carcinomas.
authors: Department of Diagnostic Radiology and Oncology, Graduate School, Tokyo Medical and Dental University, Tokyo, Japan. Electronic address: yamada.crad@tmd.ac.jp.
authors: Ichiro
authors: I
authors: Yamada
authors: Department of Pediatrics, Perinatal and Maternal Medicine, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Naoyuki
authors: N
authors: Miyasaka
authors: Department of Physiology, Keio University School of Medicine, Tokyo, Japan; Central Institute for Experimental Animals, Kanagawa, Japan.
authors: Keigo
authors: K
authors: Hikishima
authors: Department of Esophagogastric Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Yutaka
authors: Y
authors: Tokairin
authors: Department of Esophagogastric Surgery, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Tatsuyuki
authors: T
authors: Kawano
authors: Department of Pathology, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Eisaku
authors: E
authors: Ito
authors: Department of Pathology, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Daisuke
authors: D
authors: Kobayashi
authors: Department of Pathology, Tokyo Medical and Dental University, Tokyo, Japan.
authors: Yoshinobu
authors: Y
authors: Eishi
authors: Department of Physiology, Keio University School of Medicine, Tokyo, Japan.
authors: Hideyuki
authors: H
authors: Okano
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D001706:Biopsy; D002277:Carcinoma / Q000473:pathology*; D004938:Esophageal Neoplasms / Q000473:pathology*; D005260:Female; D006801:Humans; D007089:Image Enhancement / Q000379:methods*; D007090:Image Interpretation, Computer-Assisted / Q000379:methods*; D008279:Magnetic Resonance Imaging / Q000379:methods*; D008297:Male; D008875:Middle Aged; D009361:Neoplasm Invasiveness; D011829:Radiation Dosage; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
keywords: Esophageal carcinoma; Esophagus; MR imaging; Ultra-high field strength; Ultra-high spatial resolution