Validation of RAH VQ SPECT/CT lobar quantification program using a modified version of GE Q lung

Chong Ghee Chew, Benjamin Crouch, Stirling Ha, Alice Burke, Jennie Louise

Research output: Contribution to journalArticlepeer-review


Objective: The value of ventilation-perfusion (VQ) single photon emission tomography/computed tomography (SPECT/CT) lobar quantication for pre-operative assessment of lobectomy and lung volume reduction is known. Our in-house developed software, RAH ventilation perfusion SPECT/CT quantication (RAHVQSQ) has been shown to be able to identify the target lobe for collapse in bronchoscopic lung volume reduction (BLVR) for advanced emphysema. We have proven inter and intra observer reproducibility but are yet to validate the accuracy of our program. This study aims to validate the accuracy of our quantitative program through comparison with a modied version of GE Q lung which is a commercial program certied for clinical use. Subjects and Methods: Ventilation-perfusion SPECT/CT data of 19 subjects from our previous study using RAHVQSQ for BLVR assessment were re-analysed using Q lung by 2 technologists independently and in a blinded fashion to determine lobar dierential ventilation, perfusion and volume percentages. The data were from GE Hawkeye 4 and external CT, thus a modied version of Q lung was used. To determine interobserver variation in the 3 parameters between the 3 assessors, intraclass correlation coecient (ICC) and Bland-Altman limits of agreement (LoA) were generated. Results: Paired comparisons between the 3 assessors had high ICC (range for ventilation: 0.69-0.97; perfusion: 0.69-0.97; volume: 0.63-0.97) and means of LoA dierences close to zero (range for ventilation: -0.04 - 0.10; perfusion: 0.00-0.02; volume: -0.12 - 0.09) were noted indicative of good concordance for all parameters. Conclusion: Using VQ SPECT/CT data of participants with advanced airway disease, our study has found a close concordance of estimated dierential lobar ventilation, perfusion and volume percentages using RAHVQSQ when compared with a duplicated blinded assessment using Q lung. The good concordance supports the validity of our quantitative methodology.

Original languageEnglish
Pages (from-to)9-19
Number of pages11
JournalHellenic journal of nuclear medicine
Issue number1
Publication statusPublished or Issued - Jan 2023
Externally publishedYes


  • Emphysema
  • Lobar Quantication

ASJC Scopus subject areas

  • Medicine(all)

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