Lamya Eissa1, Ahmed Abdel Khalek Abdel Razek2, Eman Helmy1. 1. Department of Radiodiagnosis, Alexandria Faculty of Medicine, Alexandria, Egypt; Department of Diagnostic Radiology, Mansoura Faculty of Medicine, Mansoura, Egypt. 2. Department of Radiodiagnosis, Alexandria Faculty of Medicine, Alexandria, Egypt; Department of Diagnostic Radiology, Mansoura Faculty of Medicine, Mansoura, Egypt. Electronic address: arazek@mans.edu.eg.
Abstract
PURPOSE: To assess arterial spin-labeling (ASL) and diffusion-weighted imaging (DWI) and in combination for differentiating between idiopathic orbital inflammatory pseudotumor (IOIP) and orbital lymphoma. MATERIAL AND METHODS: A retrospective study was done on 37 untreated patients with orbital masses, suspected to be IOIP or orbital lymphoma that underwent ASL and DWI of the orbit. Quantitative measurement of tumor blood flow (TBF) and apparent diffusion coefficient (ADC) of the orbital lesion was done. RESULTS: There was a significant difference (P = 0.001) in TBF between patients with IOIP (n = 21) (38.1 ± 6.2, 40.3 ± 7.1 ml/100 g/min) and orbital lymphoma (n = 16) (55.5 ± 7.1, 56.8 ± 7.9 ml/100 g/min) for both observers respectively. Thresholds of TBF used for differentiating IOIP from orbital lymphoma were 48, 46 ml/100 g/min revealed area under the curve (AUC) of (0.958 and 0.921), and accuracy of (86% and 83%) for both observers respectively. There was a significant difference (P = 0.001) in ADC between patients with IOIP (1.04 ± 0.19, 1.12 ± 0.23 × 10-3 mm2/s) and orbital lymphoma (0.69 ± 0.10, 0.72 ± 0.11 × 10-3 mm2/s) for both observers respectively. Thresholds of ADC used for differentiating IOIP from orbital lymphoma were 0.84 and 0.86 × 10-3 mm2/s with AUC of (0.933 and 0.920), and accuracy of 89% and 90% for both observers respectively. The combined TBF and ADC used for differentiating IOIP from orbital lymphoma had AUC of (0.973 and 0.970) and accuracy of (91% and 89%) for both observers respectively. CONCLUSION: TBF and ADC alone and in combination are useful for differentiating IOIP from orbital lymphoma.
PURPOSE: To assess arterial spin-labeling (ASL) and diffusion-weighted imaging (DWI) and in combination for differentiating between idiopathic orbital inflammatory pseudotumor (IOIP) and orbital lymphoma. MATERIAL AND METHODS: A retrospective study was done on 37 untreated patients with orbital masses, suspected to be IOIP or orbital lymphoma that underwent ASL and DWI of the orbit. Quantitative measurement of tumor blood flow (TBF) and apparent diffusion coefficient (ADC) of the orbital lesion was done. RESULTS: There was a significant difference (P = 0.001) in TBF between patients with IOIP (n = 21) (38.1 ± 6.2, 40.3 ± 7.1 ml/100 g/min) and orbital lymphoma (n = 16) (55.5 ± 7.1, 56.8 ± 7.9 ml/100 g/min) for both observers respectively. Thresholds of TBF used for differentiating IOIP from orbital lymphoma were 48, 46 ml/100 g/min revealed area under the curve (AUC) of (0.958 and 0.921), and accuracy of (86% and 83%) for both observers respectively. There was a significant difference (P = 0.001) in ADC between patients with IOIP (1.04 ± 0.19, 1.12 ± 0.23 × 10-3 mm2/s) and orbital lymphoma (0.69 ± 0.10, 0.72 ± 0.11 × 10-3 mm2/s) for both observers respectively. Thresholds of ADC used for differentiating IOIP from orbital lymphoma were 0.84 and 0.86 × 10-3 mm2/s with AUC of (0.933 and 0.920), and accuracy of 89% and 90% for both observers respectively. The combined TBF and ADC used for differentiating IOIP from orbital lymphoma had AUC of (0.973 and 0.970) and accuracy of (91% and 89%) for both observers respectively. CONCLUSION:TBF and ADC alone and in combination are useful for differentiating IOIP from orbital lymphoma.
Authors: Michaela Cellina; Maurizio Cè; Giovanni Irmici; Carlo Martinenghi; Sara Marziali; Natallia Khenkina; Anna Maria Ierardi; Giancarlo Oliva; Gianpaolo Carrafiello Journal: Emerg Radiol Date: 2022-04-14