Summary of Section 7: Diagnosis of FIP; Section 7.4: Diagnostic imaging in FIP:  No specific ultrasonographic or radiographic findings exist for FIP.  Ultrasonography (in particular) and radiography can show the presence of effusions. Pneumonia due to FIP that is occasionally reported can be associated with radiographic changes. Ultrasonography can reveal abdominal lymphadenomegaly or lymphadenopathy and/or abnormalities of the liver, spleen, intestines and/or kidneys (which can include a medullary rim sign), depending on which organs are affected. Imaging can also be of use to the direct sampling of abnormal tissues, e.g., fine-needle aspirate for cytology examination to reveal non-septic pyogranulomatous inflammation, or ultrasound-guided needle core (e.g., tru-cut) biopsies can be collected and submitted for histopathology.  When a cat is showing neurological signs, the imaging of the brain by magnetic resonance imaging, if available, with contrast, can be useful to demonstrate neurological abnormalities (such as obstructive hydrocephalus, syringomyelia, foramen magnum herniation and marked contrast enhancement of the meninges, third ventricle, mesencephalic aqueduct, and brainstem). A description of computerised tomography findings in cats with neurological FIP has not been published, but MRI is likely to be more sensitive in the detection of subtle intraparenchymal lesions. Advanced imaging of the central nervous system is indicated before performing cerebrospinal fluid sampling to assess the potential risk of herniation.