RESUMEN
Intracranial artery dissection is rare in the clinic, but could account for a large proportion of young patients with intracranial vascular diseases. High-resolution magnetic resonance imaging is a direct method of vessel wall imaging and widely used in clinical practice due to advantages including high spatial resolution, high signal-to-noise ratio and strong reproducibility. The article briefly introduces the typical findings of intracranial artery dissection in high-resolution magnetic resonance imaging and the unique advantages of features such as intimal flap, double-lumen, lumen diameter change and intramural hematoma. It makes up for the deficiency of traditional lumen imaging in the diagnosis and differential diagnosis of intracranial artery dissection, providing a strong basis for the diagnosis and intervention of intracranial vascular dissection.
RESUMEN
Objective To investigate the values of conventional magnetic resonance imaging (MRI),magnetic resonance angiography (MRA),and high-resolution MRI for diagnosing intracranial arterial dissection (IAD)caused ischemic stroke. Methods From August 2008 to April 2015,59 consecu-tive patients (age 45 ±15years,41males)with IAD caused ischemic stroke admitted to the First Affiliated Hos-pital of Sun Yat-Sen University were enrolled prospectively. All patients underwent conventional cranial MRI/MRA examination,25 of them underwent whole brain DSA examination,and 10 underwent high-resolution MRI. The findings of conventional MRI/ MRA and high-resolution MRI of IAD were analyzed. For patients undergoing DSA,the proportions of detection and compliance of IAD were compared between DSA and conventional MRI / MRA. Results (1)Conventional MRI / MRA revealed typical sign of artery dissection in 42 patients (71. 2%),among them,the intramural hematoma (n = 22,52. 4%)was most common. Other common signs included intimal flap/ double lumen sign (n = 13,31. 0%)and long irregular or thread-like stenosis (n = 9,21. 4%);while dissecting aneurysm (n = 7,16. 7%)and rat tail-shaped occlusion (n = 3, 7. 1%)were relatively rare. In 17 patients (28. 8%)with IAD that conventional MRI/ MRA did not detect the typical dissection sign,the dissections were involved in the middle cerebral artery (11 / 17,64. 7%), they were more common than the 42 patients with IAD (10 / 42,23. 8%)detected the typical dissection sign by conventional MRI/ MRA. There was significant difference (P = 0. 006). (2)Among the 25 patients undergoing DSA,DSA revealed that 15 patients (60%)had the typical dissection sign,and conventional MRI/ MRA only revealed 8 of them (32%)with the typical dissection sign,but there was no significant difference (P = 0. 088). In 15 patients with IAD that DSA detected the typical dissection sign;conventional MRI / MRA detected the typical dissection sign in 8 of them. The diagnostic coincidence rate was 8 / 15. (3)Both conventional MRI/ MRA and DSA revealed non-specific limitation stenosis or cut-off occlusion in 10 patients (16. 9%)with IAD,while the high-resolution MRI revealed intimal flap in 5 of them,intramural hematoma in 4,and intimal flap and intramural hematoma in 1. Conclusion Conventional cranial MRI/MRA is an effective technique for revealing IAD,whereas high-resolution MRI has the unique advantages for diagnosing IAD without typical dissection in other vascular imaging.