Imaging-based algorithmic approach to gallbladder wall thickening

Table 5 Rare causes of gallbladder wall thickening and their imaging findings

Cause	CT findings
Tuberculosis	(1) micronodular type: Micronodular or polypoidal lesions in GB wall; (2) thickened wall type: Most common. Diffuse or focal, nonspecific, homogeneous, or heterogeneous enhancement. Halo of edema may be present; and (3) mass-forming type: Large mass with multicentric necrosis and foci of calcification
Primary lymphoma	(1) high grade: Solid and bulky mass in the GB fossa or marked GB wall thickening; (2) low grade: Mild GB wall thickening with intact mucosa
Neuroendocrine tumor	Most common as mass replacing GB with well-defined margins and intact mucosa as compared to GBC. Arterial hyperenhancement. More extensive and bulky lymph node and hepatic metastasis compared to GBC

CT: Computed tomography; GB: Gallbladder; GBC: Gallbladder carcinoma.