title: Evaluation of image reconstruction methods for (123)I-MIBG-SPECT: a rank-order study.
abstract: BACKGROUND
  There is an opportunity to improve the image quality and lesion detectability in single photon emission computed tomography (SPECT) by choosing an appropriate reconstruction method and optimal parameters for the reconstruction.
  
  
  OBJECTIVE
  To optimize the use of the Flash 3D reconstruction algorithm in terms of equivalent iteration (EI) number (number of subsets times the number of iterations) and to compare with two recently developed reconstruction algorithms ReSPECT and orthogonal polynomial expansion on disc (OPED) for application on (123)I-metaiodobenzylguanidine (MIBG)-SPECT.
  
  
  METHODS
  Eleven adult patients underwent SPECT 4 h and 14 patients 24 h after injection of approximately 200 MBq (123)I-MIBG using a Siemens Symbia T6 SPECT/CT. Images were reconstructed from raw data using the Flash 3D algorithm at eight different EI numbers. The images were ranked by three experienced nuclear medicine physicians according to their overall impression of the image quality. The obtained optimal images were then compared in one further visual comparison with images reconstructed using the ReSPECT and OPED algorithms.
  
  
  RESULTS
  The optimal EI number for Flash 3D was determined to be 32 for acquisition 4 h and 24 h after injection. The average rank order (best first) for the different reconstructions for acquisition after 4 h was: Flash 3D(32) > ReSPECT > Flash 3D(64) > OPED, and after 24 h: Flash 3D(16) > ReSPECT > Flash 3D(32) > OPED. A fair level of inter-observer agreement concerning optimal EI number and reconstruction algorithm was obtained, which may be explained by the different individual preferences of what is appropriate image quality.
  
  
  CONCLUSIONS
  Using Siemens Symbia T6 SPECT/CT and specified acquisition parameters, Flash 3D(32) (4 h) and Flash 3D(16) (24 h), followed by ReSPECT, were assessed to be the preferable reconstruction algorithms in visual assessment of (123)I-MIBG images.
authors: Medical Radiation Physics, Department of Clinical Sciences Malmö, Lund University, Skåne University Hospital, SE-205 02 Malmö, Sweden. marcus.soderberg@med.lu.se
authors: Marcus
authors: M
authors: Söderberg
authors: Sören
authors: S
authors: Mattsson
authors: Jenny
authors: J
authors: Oddstig
authors: Helena
authors: H
authors: Uusijärvi-Lizana
authors: Sven
authors: S
authors: Valind
authors: Ola
authors: O
authors: Thorsson
authors: Sabine
authors: S
authors: Garpered
authors: Tilmann
authors: T
authors: Prautzsch
authors: Oleg
authors: O
authors: Tischenko
authors: Sigrid
authors: S
authors: Leide-Svegborn
mesh_terms: D019797:3-Iodobenzylguanidine / Q000008:administration & dosage; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000465:Algorithms; D005260:Female; D006801:Humans; D007091:Image Processing, Computer-Assisted / Q000379:methods; D021621:Imaging, Three-Dimensional / Q000379:methods*; D007275:Injections, Intravenous; D008297:Male; D008875:Middle Aged; D019275:Radiopharmaceuticals / Q000008:administration & dosage; D018709:Statistics, Nonparametric; D015899:Tomography, Emission-Computed, Single-Photon / Q000379:methods*
chemical_list: D019275:Radiopharmaceuticals; D019797:3-Iodobenzylguanidine