Manifestations include eyelid or periocular swelling, lacrimal gland enlargement, extraocular muscle involvement, intraorbital mass, proptosis, and cranial nerve V involvement. CT CT of the orbits with contrast is often the initial imaging modality in the emergent setting for suspected infection [2,7,42,43]. CT is superior to MRI for foreign body assessment, calcification detection, and osseous evaluation [43]. CT can be used in conjunction with the Chandler criteria to evaluate for the presence of bone erosion and subperiosteal abscess, which may require surgical intervention [38,44-46]. Imaging findings may show bone erosion on CT, opacification of a neighboring infected sinus, and/or intraorbital extension of inflammatory disease [47]. In patients who cannot receive contrast, a noncontrast orbit CT may still add useful information. Precontrast and postcontrast imaging is typically not necessary in evaluating these patients as the precontrast images do not add significant diagnostic information in this scenario. Currently there is no consensus on the optimal imaging modality to assess patients presenting with IOIS or IgG4- related orbital disease. Orbital CT and MRI are often complementary in their roles. Signs of inflammation may be detected with CT or MRI, which show intraconal or extraconal soft-tissue lesions that are diffuse or localized and commonly involve the orbital apex [43,48]. These findings may be initially seen on CT and subsequently further evaluated with MRI for improved soft-tissue characterization. MRI Orbital MRI is complementary to CT in evaluating intraorbital spread of infection. An MRI of the orbits without and with contrast should be considered if a more detailed assessment of intraorbital spread of infection is clinically warranted. In patients with suspected intracranial extension or complications, an MRI of the brain with high-resolution images to include the cavernous sinuses [2,42,43,46,47] provides greater soft-tissue resolution than CT.
Orbits Vision and Visual Loss. Manifestations include eyelid or periocular swelling, lacrimal gland enlargement, extraocular muscle involvement, intraorbital mass, proptosis, and cranial nerve V involvement. CT CT of the orbits with contrast is often the initial imaging modality in the emergent setting for suspected infection [2,7,42,43]. CT is superior to MRI for foreign body assessment, calcification detection, and osseous evaluation [43]. CT can be used in conjunction with the Chandler criteria to evaluate for the presence of bone erosion and subperiosteal abscess, which may require surgical intervention [38,44-46]. Imaging findings may show bone erosion on CT, opacification of a neighboring infected sinus, and/or intraorbital extension of inflammatory disease [47]. In patients who cannot receive contrast, a noncontrast orbit CT may still add useful information. Precontrast and postcontrast imaging is typically not necessary in evaluating these patients as the precontrast images do not add significant diagnostic information in this scenario. Currently there is no consensus on the optimal imaging modality to assess patients presenting with IOIS or IgG4- related orbital disease. Orbital CT and MRI are often complementary in their roles. Signs of inflammation may be detected with CT or MRI, which show intraconal or extraconal soft-tissue lesions that are diffuse or localized and commonly involve the orbital apex [43,48]. These findings may be initially seen on CT and subsequently further evaluated with MRI for improved soft-tissue characterization. MRI Orbital MRI is complementary to CT in evaluating intraorbital spread of infection. An MRI of the orbits without and with contrast should be considered if a more detailed assessment of intraorbital spread of infection is clinically warranted. In patients with suspected intracranial extension or complications, an MRI of the brain with high-resolution images to include the cavernous sinuses [2,42,43,46,47] provides greater soft-tissue resolution than CT.