MRA without and with contrast may be preferred over CTA if time-resolved information is needed in lesion characterization. DSA is not a first-line test in this scenario. Radiography Orbital or skull radiographs are insufficient to detect pathology in patients presenting with monocular vision loss. Variant 7: Nonischemic visual loss. Chiasm or post-chiasm symptoms. Initial imaging. If a patient presents with a junctional scotoma or bitemporal hemianopia, a parasellar lesion is suspected, with mass effect on the optic chiasm affecting the crossing temporal fibers. Lesions may arise from the pituitary gland, hypothalamus, or adjacent dura, and accompanying endocrine abnormalities may also be present. Slowly progressive binocular visual defect findings suggest an intracranial or skull-base abnormality, including primary neoplasms and metastatic lesions. Mass effect from other intracranial pathology, including abscess, multiple sclerosis, or vascular lesions such as arteriovenous malformations and cerebral aneurysms, may also present with a similar visual field deficit. Orbits, Vision and Visual Loss MRI Patients with a junctional scotoma or bitemporal visual defect are best assessed with an MRI of the brain without and with contrast, which includes the thin-slice profile needed to evaluate the pituitary gland and any suprasellar mass effect [43]. Detailed assessment of the optic chiasm and its relationship to an underlying mass are easily seen with an MRI of the brain without and with contrast. If contrast cannot be given, an MRI of the brain without contrast may be appropriate. Patients presenting with a homonymous hemianopia or quadrantanopia defect are best assessed with an MRI of the brain without and with contrast [2,7,59-61]. Because the defect is most likely in a post-chiasm location, additional smaller field-of-view images of the orbit are typically not necessary.
Orbits Vision and Visual Loss. MRA without and with contrast may be preferred over CTA if time-resolved information is needed in lesion characterization. DSA is not a first-line test in this scenario. Radiography Orbital or skull radiographs are insufficient to detect pathology in patients presenting with monocular vision loss. Variant 7: Nonischemic visual loss. Chiasm or post-chiasm symptoms. Initial imaging. If a patient presents with a junctional scotoma or bitemporal hemianopia, a parasellar lesion is suspected, with mass effect on the optic chiasm affecting the crossing temporal fibers. Lesions may arise from the pituitary gland, hypothalamus, or adjacent dura, and accompanying endocrine abnormalities may also be present. Slowly progressive binocular visual defect findings suggest an intracranial or skull-base abnormality, including primary neoplasms and metastatic lesions. Mass effect from other intracranial pathology, including abscess, multiple sclerosis, or vascular lesions such as arteriovenous malformations and cerebral aneurysms, may also present with a similar visual field deficit. Orbits, Vision and Visual Loss MRI Patients with a junctional scotoma or bitemporal visual defect are best assessed with an MRI of the brain without and with contrast, which includes the thin-slice profile needed to evaluate the pituitary gland and any suprasellar mass effect [43]. Detailed assessment of the optic chiasm and its relationship to an underlying mass are easily seen with an MRI of the brain without and with contrast. If contrast cannot be given, an MRI of the brain without contrast may be appropriate. Patients presenting with a homonymous hemianopia or quadrantanopia defect are best assessed with an MRI of the brain without and with contrast [2,7,59-61]. Because the defect is most likely in a post-chiasm location, additional smaller field-of-view images of the orbit are typically not necessary.