Magnetic Resonance Appearance of asbestos-related Benign and Malignant Pleural Diseases

• Published in: Scandinavian Journal of Work, Environment ＆ Health Vol. 25; no. 1; pp. 18 - 23
• Main Authors: Boraschi, Piero, Neri, Silvano, Braccini, Giovanni, Gigoni, Roberto, Leoncini, Benito, Perri, Giuseppe
• Format: Journal Article
• Language: English
• Published: Helsinki Scandinavian Journal of Work, Environment ＆ Health 01.02.1999; National Institute for Working Life; Finnish Institute of Occupational Health; National Institute of Occupational Health (Denmark); National Institute of Occupational Health (Norway); Scandinavian journal of work, environment & health
• Subjects: Adult; Aged; Aged, 80 and over; Asbestos - adverse effects; Biological and medical sciences; Computerized axial tomography; Diagnosis, Differential; Female; Humans; Image contrast; Image enhancement; Imaging; Investigative techniques, diagnostic techniques (general aspects); Lesions; Magnetic resonance; Magnetic Resonance Imaging; Male; Medical sciences; Mesothelioma; Mesothelioma - etiology; Mesothelioma - pathology; Middle Aged; Occupational Exposure - adverse effects; Pleural diseases; Pleural Diseases - etiology; Pleural Diseases - pathology; Radiodiagnosis. Nmr imagery. Nmr spectrometry; Respiratory system; Tumors; pleura; pleura, mesothelioma; magnetic resonance, tissue characterization; pleura, plaques; preliminaly study; Human; Evaluation; Asbestos; Respiratory disease; Magnetic resonance; Malignant tumor; Occupational exposure; Industry; Malignant mesothelioma; Sensitivity; Specificity; Benign mesothelioma; Investigation method; Pleural disease; Medical imagery; Benign neoplasm; Diagnostic aid; Occupational medicine; Pleura
• ISSN: 0355-3140; 1795-990X
• DOI: 10.5271/sjweh.378

Objectives This study describes the magnetic resonance findings of benign and malignant pleural diseases in asbestos-exposed subjects. Methods Thirty patients with a history of asbestos exposure and pleural lesions in chest X-rays and computed tomography scans were examined with a 0.5-and a 1.5-T magnetic resonance unit. The examination protocol included cardiac-gated proton density and T2-weighted images, unenhanced and enhanced (Gd-DTPA; 0.1 mmol/kg) Tl-weighted images in the axial plane and sometimes in another orthogonal plane (sagittal or coronal or both). All the magnetic resonance images were reviewed by 3 experienced observers, who visually evaluated morphologic features, signal intensity, and contrast enhancement of pleural lesions. The diagnosis was established by means of percutaneous biopsy, thoracotomy, and combined clinical and radiological follow-up for at least 3 years. Results Eighteen patients affected with multiple pleural plaques showed low signal intensity on both unenhanced and enhanced Tl-weighted and proton density and T2-weighted images. In 2 of these patients an acute pleural effusion was observed. All the malignant lesions (11 mesotheliomas) and a solitary benign pleural plaque revealed high signal intensity on the proton density and T2-weighted images and inhomogeneous contrast enhancement in the postcontrast Tl-weighted images. The sensitivity, specificity, and diagnostic accuracy of the magnetic resonance imaging in classifying a lesion as suggestive of malignancy were 100%, 95% and 97%, respectively. Conclusions The results point out 2 magnetic resonance signal intensity patterns for asbestos-related pleural lesions: (i) low-signal intensity on unenhanced and enhanced Tl-weighted and proton density and T2-weighted images for benign plaques and (ii) nonhomogeneous hyperintensity in T2-weighted and enhanced T1-weighted images for malignant mesotheliomas.