Photon-counting computed tomography in the assessment of rheumatoid arthritis-associated interstitial lung disease: an initial experience

Nikolett Marton; Janos Gyebnar; Kinga Fritsch; Judit Majnik; Gyorgy Nagy; Judit Simon; Veronika Müller; Adam Domonkos Tarnoki; David Laszlo Tarnoki; Pal Maurovich-Horvat

doi:10.4274/dir.2023.221959

Photon-counting computed tomography in the assessment of rheumatoid arthritis-associated interstitial lung disease: an initial experience

Diagn Interv Radiol. 2023 Mar 29;29(2):291-299. doi: 10.4274/dir.2023.221959. Epub 2023 Mar 8.

Authors

Nikolett Marton¹, Janos Gyebnar¹, Kinga Fritsch², Judit Majnik^{2

3}, Gyorgy Nagy^{2

3}, Judit Simon^{1

4}, Veronika Müller⁵, Adam Domonkos Tarnoki^{1

6}, David Laszlo Tarnoki^{1

6}, Pal Maurovich-Horvat¹

Affiliations

¹ Department of Radiology, Medical Imaging Centre, Semmelweis University, Budapest, Hungary
² Department of Rheumatology, Buda Hospital of the Hospitaller Order of Saint John of God, Budapest, Hungary
³ Department of Rheumatology and Clinical Immunology, Semmelweis University, Budapest, Hungary
⁴ MTA-SE Cardiovascular Imaging Research Group, Semmelweis University, Budapest, Hungary
⁵ Department of Pulmonology, Semmelweis University, Budapest, Hungary
⁶ Department of Oncologic Imaging and Invasive Diagnostic Radiology, National Institute of Oncology, Budapest, Hungary

Abstract

Purpose: Interstitial lung disease (ILD) accounts for a significant proportion of mortality and morbidity in patients with rheumatoid arthritis (RA). The aim of this cross-sectional study is to evaluate the performance of novel photon-counting detector computed tomography (PCD-CT) in the detection of pulmonary parenchymal involvement.

Methods: Sixty-one patients with RA without a previous definitive diagnosis of ILD underwent high-resolution (HR) (0.4 mm slice thickness) and ultra-high-resolution (UHR) (0.2 mm slice thickness) PCDCT examination. The extent of interstitial abnormalities [ground-glass opacity (GGO), reticulation, bronchiectasis, and honeycombing] were scored in each lobe using a Likert-type scale. Total ILD scores were calculated as the sum of scores from all lobes.

Results: Reticulation and bronchiectasis scores were higher in the UHR measurements taken compared with the HR protocol [median (quartile 1, quartile 3): 2 (0, 3.5) vs. 0 (0, 3), P < 0.001 and 2 (0, 2) vs. 0 (0, 2), P < 0.001, respectively]; however, GGO and honeycombing scores did not differ [2 (2, 4) vs. 2 (2, 4), P = 0.944 and 0 (0, 0) vs. 0 (0, 0), P = 0.641, respectively]. Total ILD scores from both HR and UHR scans showed a mild negative correlation in diffusion capacity for carbon monoxide (HR: r = -0.297, P = 0.034; UHR: r = -0.294, P = 0.036). The pattern of lung parenchymal involvement did not differ significantly between the two protocols. The HR protocol had significantly lower volume CT dose index [0.67 (0.69, 1.06) mGy], total dose length product [29 (24.48, 33.2) mGy*cm] compared with UHR scans [8.18 (6.80, 9.23) mGy, P < 0.001 and 250 (218, 305) mGy*cm, P < 0.001].

Conclusion: UHR PCD-CT provides more detailed information on ILD in patients with RA than low-dose HR PCDCT. HR PCD-CT image acquisition with a low effective radiation dose may serve as a valuable, low-radiation screening tool in the selection of patients for further, higher-dose UHR PCD-CT screening.

Keywords: CT; high-resolution; low-dose; lung; photon-counting; ultra-high-resolution.

MeSH terms

Arthritis, Rheumatoid* / complications
Arthritis, Rheumatoid* / diagnostic imaging
Bronchiectasis* / complications
Bronchiectasis* / diagnostic imaging
Cross-Sectional Studies
Cysts*
Humans
Lung Diseases, Interstitial* / diagnostic imaging
Lung Diseases, Interstitial* / etiology
Tomography, X-Ray Computed / methods