title: Multidetector CT with 3-dimensional volume rendering in the evaluation of the spine in patients with Neurofibromatosis type 1: a retrospective review in 73 patients.
abstract: BACKGROUND
  Neurofibromatosis type 1 (NF-1) may involve the spine as various abnormalities including bony dysplasia, scoliosis, and nerve sheath tumors. Surgery may be performed for stabilization of the spine. We have seen an increase in requests for multidetector CT (MDCT) imaging with the (three-dimensional) 3D-volume rendered (VR) images in patients evaluated at our institution. We, therefore, investigated how MDCT could be best utilized in this patient population.
  
  
  METHODS
  Seventy-three patients with NF-1 were identified in whom MDCT imaging was performed for diagnostic, pre-operative, or post-operative evaluation of spinal abnormalities. True axial source images and two dimensional (2D) orthogonal reconstructed MDCT images, as well as the VR images, were compared with plain radiographs and MRI. In addition, the MDCT study was compared to the VR images. These studies were reviewed to compare assessment of A) bony abnormalities such as remodeling from dural ectasia, dysplasia, and fusion, B) abnormal spinal curvature, C) nerve sheath tumors, and D) surgical instrumentation.
  
  
  RESULTS
  When compared to plain radiographs, the MDCT and VR images were rated as helpful for evaluating the abnormalities of the spine in 19 of 24 patients for a total of 30 findings. This included the following categories A) (n = 6), B) (n = 5), C) (n = 7), and D) (n = 12). Compared to MR, the MDCT and VR study was helpful in evaluating the findings of NF-1 in 24 of 36 patients for a total of 40 findings. This included the following categories A) (n = 12), B) (n = 10), C) (n = 3), and D) (n = 15). When the VR images were compared to the orthogonal MDCT, the VR images was rated as helpful in 41 of 73 patients for a total of 60 findings, including the following categories: A) (n = 11), B) (n = 24), C) (n = 0), and D) (n = 25).
  
  
  CONCLUSIONS
  MDCT has distinct advantages over plain radiographs and MR imaging, and the VR images over MDCT in the evaluation of the spine in patients with NF-1, especially for the assessment of bony abnormalities, abnormal spinal curvature, and spinal instrumentation.
authors: Department of Radiology, Section of Neuroradiology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Unit 370, Houston, TX 77030, USA.
authors: James Matthew
authors: JM
authors: Debnam
authors: Department of Radiology, National Cancer Institute, Cairo, Egypt.
authors: Yasser Mm
authors: YM
authors: Mahfouz
authors: Department of Radiology, Section of Neuroradiology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Unit 370, Houston, TX 77030, USA.
authors: Leena
authors: L
authors: Ketonen
authors: Department of Neuro-Oncology, The University of Texas M.D. Anderson Cancer Center, Houston TX 77030, USA.
authors: John M
authors: JM
authors: Slopis
authors: Department of Neurosurgery, The University of Texas M.D. Anderson Cancer Center, Houston, TX 77030, USA.
authors: Ian E
authors: IE
authors: McCutcheon
authors: Department of Radiology, Section of Neuroradiology, The University of Texas M.D. Anderson Cancer Center, 1515 Holcombe Blvd., Unit 370, Houston, TX 77030, USA.
authors: Nandita
authors: N
authors: Guha-Thakurta
keywords: Abnormalities; Computed tomography; Computer-assisted three dimensional imaging; Neurofibromatosis 1; Spine