Clinics in diagnostic imaging (102).

A 19-year-old man presented with cough and haemoptysis of ten days duration. He also had mild right hypochondrial pain. Chest radiograph and computed tomography (CT) showed a rounded soft tissue density opacity with an air crescent sign. CT showed multiple cystic lesions in the liver with a daughter cyst in its lateral wall. Diagnosis of hydatid disease of lung and liver was made. The contents of the liver cyst were aspirated, hypertonic saline instilled, re-aspirated, and absolute alcohol injected. Hydatid disease is endemic in certain parts of the world. Although the lungs and liver are most frequently affected, the disease can arise in any part of the body and should be kept in differential diagnosis whenever a cystic lesion is encountered. Hydatid cysts typically demonstrate characteristic imaging findings, however, the appearances may become complicated due to cyst rupture or secondary infection. Ultrasonography is the imaging modality of choice particularly in hepatic disease. CT best demonstrates cyst wall calcification and cyst infection.

Magnetic resonance imaging findings in tuberculous meningoencephalitis.

OBJECTIVE: To evaluate the efficacy of magnetic resonance imaging (MRI) for distinguishing tuberculosis from other types of meningoencephalitis. PATIENTS AND METHODS: MRIs of 100 patients with tuberculous (50), pyogenic (33), viral (14), or fungal (3) meningoencephalitis were analyzed independently by 2 radiologists. Number, size, location, signal characteristics, surrounding edema, and contrast enhancement pattern of nodular lesions; location and pattern of meningeal enhancement; extent of infarct or encephalitis and hydrocephalus were evaluated. RESULTS: Contrast-enhancing nodular lesions were detected in patients with tuberculous (43 of 50 patients), pyogenic (9 of 33), and fungal (3 of 3) infections. No nodules were detected in patients with viral meningoencephalitis. Using the criteria of 1 or more solid rim or homogeneously enhancing nodules smaller than 2 cm, the sensitivity, specificity and accuracy for diagnosing tuberculous meningitis were 86.0%, 90.0% and 88.0%, respectively. CONCLUSION: Magnetic resonance imaging is useful in distinguishing tuberculous from pyogenic, viral and fungal meningoencephalitis.