Prager J M, Mikulis D J
Department of Radiology, University of Chicago, Illinois.
Med Clin North Am. 1991 May;75(3):525-44. doi: 10.1016/s0025-7125(16)30431-x.
The patient who presents with a severe and acute headache should be evaluated radiographically with CT. The key diagnosis to make in this situation is hemorrhage, either subarachnoid or intraparenchymal. Computed tomography is more sensitive to acute hemorrhage than is MRI. When the patient is stable, MRI frequently contributes information to narrow the diagnostic possibilities, because vascular malformations and certain parenchymal lesions have a characteristic appearance on MRI. Hydrocephalus may also present acutely and is easily seen on CT or MRI. In a patient may show WMF and atrophy. The patient with trigeminal neuropathy may demonstrate central or peripheral lesions. In temporomandibular joint dysfunction, conventional tomography and MRI are frequently used. Magnetic resonance imaging shows excellent detail of the disk and surrounding soft tissues, whereas tomography better demonstrates bony changes. When a history of trauma is present, MRI may show a subacute subdural hematoma. These collections are easily seen on MRI, even when isodense on CT. Evidence of old shear injury is also well seen on MRI. Finally, neoplastic, inflammatory, congenital, and idiopathic sources of headache may be demonstrated by either MRI or CT, depending on presentation. MRI will generally show superior characterization.
出现严重急性头痛的患者应进行CT影像学评估。这种情况下的关键诊断是出血，无论是蛛网膜下腔出血还是脑实质内出血。计算机断层扫描对急性出血比磁共振成像更敏感。当患者病情稳定时，磁共振成像常常有助于提供信息以缩小诊断范围，因为血管畸形和某些脑实质病变在磁共振成像上有特征性表现。脑积水也可能急性出现，在CT或磁共振成像上很容易看到。在患者中可能显示白质病变和萎缩。三叉神经病变患者可能显示中枢或周围病变。在颞下颌关节功能障碍中，常使用传统体层摄影术和磁共振成像。磁共振成像能很好地显示椎间盘及周围软组织的细节，而体层摄影术能更好地显示骨质变化。当有外伤史时，磁共振成像可能显示亚急性硬膜下血肿。即使这些血肿在CT上呈等密度，在磁共振成像上也很容易看到。陈旧性剪切伤的证据在磁共振成像上也能很好地显示。最后，根据表现，头痛的肿瘤性、炎症性、先天性和特发性病因可通过磁共振成像或CT显示。一般来说，磁共振成像能显示更优的特征。
