title: Comparison of 80 and 120 kVp contrast-enhanced CT for attenuation correction in PET/CT, using quantitative analysis and reporter assessment of PET image quality.
abstract: OBJECTIVE
  To determine the effect of low tube voltage on positron-emission tomography (PET) image quality, quantitative analysis, and radiation dose in a combined PET/computed tomography (CT) study in patients with normal body mass index (BMI).
  
  
  METHODS
  One hundred and twenty-nine examinations performed in 46 patients (mean age 57 years), who had at least two separate studies were retrospectively evaluated; at least one with 120 kVp and one with 80 kVp. Three independent readers reviewed all PET images and graded the image quality. PET signal and noise were recorded on the liver, spleen, fat, bone marrow, and aorta. CT dose index (CTDI) and the dose-length product (DLP) were used for CT radiation dose estimation. A mixed-effects model analysis was used for comparison of estimated radiation dose and PET data.
  
  
  RESULTS
  There was a significant decrease of 15% in the radiation dose estimates between 80 and 120 kVp (DLP 946.2 ± 189 versus 1157.0 ± 236, respectively; p < 0.001). There was an increase of 12% in PET signal in the normal liver with 80 kVp. The average score of PET image quality obtained between 80 and 120 kVp was 4.85 ± 0.42 versus 4.90 ± 0.27, respectively (p = 0.47).
  
  
  CONCLUSIONS
  PET/80 kVp CT has no statistically significant difference in the PET image quality and quantitative analysis compared to PET/120 kVp and may be used in selected patients to reduce the radiation dose.
authors.affiliation: Department of Nuclear Medicine, Rabin Medical Center, Petah Tikva, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel.
authors.forename: H
authors.initials: H
authors.lastname: Bernstine
authors.affiliation: Department of Nuclear Medicine, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: V
authors.initials: V
authors.lastname: Sopov
authors.affiliation: Department of Nuclear Medicine, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: N
authors.initials: N
authors.lastname: Yefremov
authors.affiliation: Department of Nuclear Medicine, Rabin Medical Center, Petah Tikva, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Nidam
authors.affiliation: Department of Radiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel.
authors.forename: M
authors.initials: M
authors.lastname: Gabbai
authors.affiliation: Department of Radiology, Hadassah Hebrew University Medical Center, Jerusalem, Israel; Department of Radiology, Beth Israel Deaconess Medical Center, Harvard Medical School, Boston, MA, USA.
authors.forename: J
authors.initials: J
authors.lastname: Sosna
authors.affiliation: Department of Nuclear Medicine, Rabin Medical Center, Petah Tikva, Israel; Sackler Faculty of Medicine, Tel Aviv University, Tel Aviv, Israel; Department of Nuclear Medicine, Assuta Medical Center, Tel Aviv, Israel. Electronic address: davidgr2@clalit.org.il.
authors.forename: D
authors.initials: D
authors.lastname: Groshar
mesh_terms: D015992:Body Mass Index; D003287:Contrast Media; D005260:Female; D006801:Humans; D007472:Iohexol / Q000031:analogs & derivatives; D008297:Male; D008875:Middle Aged; D064847:Multimodal Imaging; D049268:Positron-Emission Tomography / Q000379:methods*; D011829:Radiation Dosage; D012189:Retrospective Studies; D014057:Tomography, X-Ray Computed / Q000379:methods*
chemical_list: D003287:Contrast Media; D007472:Iohexol; C038192:iopromide