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Objective To explore the value of small surface coil combined with three-dimensional double-echo steady-state with water excitation (3D-DESS-WE) sequence in displaying mandibular nerves and their branches. Methods The maxillofacial regions of 52 volunteers were scanned unilaterally by a small surface coil combined with 3D-DESS-WE sequence. According to the Gray's anatomy atlas,MPR and CPR was done according to the anatomic position of mandibular nerve and the branches,the signal characteristics of the nerves and neighboring structures were analyzed. The displaying rate of the mandibular nerves and their branches were evaluated.The image quality and display of the nerve were subjectively scored. The signal intensity(SI) of the nerve and adjacent lateral pterygoid muscle were measured. The signal intensity ratio(SIR) of mandibular nerve/lateral pterygoid muscle (SIRN/M) was calculated. Results Compared with the muscles, the nerve showed iso-signal intensity. The subjective scores for all small coil 3D-DESS-WE images were 3.02 ± 0.82. The displaying rates of V3 trunk,anterior trunk,buccal nerve, posterior trunk,inferior alveolar nerve and lingual nerve were all 100%. V3 posterior trunk,inferior alveolar nerve and lingual nerve showed the best quality scores,which were all about 3 points,and the SIRN/M were about 1. The auricular temporal nerve and masseter muscle nerve were also basically satisfied. The displaying rate of mylohyoid muscle nerve,medial pterygoid nerve and lateral pterygoid nerve was low. Conclusion Small surface coil combine with 3D-DESS-WE sequence performed high-quality in mandibular nerves and their branches MR imaging using MPR,CPR post-processing technology,which are suitable for clinical application.
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Objective The present study was to investigate the feasibility of use of high resolution magnetic reso?nance vessel wall imaging(HR-VWI)in evaluation of intracranial aneurysms. Methods We prospectively collected data from patients who had intracranial aneurysms and received HR-VWI scan before surgical treatment or conservative treatment. Aneurysms were divided into ruptured group (n=12) and unruptured group (n=88). Aneurysm site, size, neck, aspect ratio(AR), daughter sac and aneurysmal wall enhancement scale were analyzed in both groups. Univariate and multivariate Logistic regression were performed to evaluate the risk factors of aneurysm rupture. Subgroup analysis was also performed to study symptomatic and asymptomatic unruptured aneurysms. Results Aneurysm size(t=2.187,P=0.031),AR(t=3.164,P=0.002),incidence of daughter sac(P=0.012) and aneurysmal wall enhancement scale(P<0.001)were higher in ruptured aneurysm group. Multivariate Logistic regression showed that aneurysmal wall enhance?ment scale was the only independent risk factor of ruptured aneurysms(P=0.002). Subgroup analysis showed aneurysm wall enhancement scale(P<0.001) and AR(t=3.939,P<0.001) were higher in symptomatic unruptured aneurysms. Conclusion Aneurysm wall enhancement on HR-VWI is more frequently seen in ruptured aneurysms and symptomatic unruptured aneurysms. Histological study is needed for better understanding of the mechanism of aneurysm wall enhance?ment.
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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.
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Objective To explore the value of small surface coil combine with three-dimensional fast imaging with steady state precession and fat-suppression (3D-FISP-FS) sequence in displaying intra-parotid facial nerves segment and parotid ducts.Methods The parotid regions of 18 healthy volunteers who were excluded any parotid diseases were scanned by head&neck coil (36 sides) and 4 cm small surface coil (32 sides) combined with 3D-FISP-FS sequence prospectively. The obtained original images were treated through MIP, MPR and CPR, The MRI signal characteristics of parotid region structure, the subjective score of image quality, the signal intensity ratio (SIR) of facial nerve/parotid tissue (SIR N) and parotid duct/parotid tissue (SIRD) was calculated, and the displaying rates of the facial nerves and parotid ducts were observed. Wilcoxon matched-samples signed rank sum test was used to compare the scores of head&neck coil and small coil 3D-FISP-FS sequence images, paired t test was used to compare SIRN, SIRD of the two groups, Chi-square test was used to compare of the displaying rate of the facial nerves and parotid ducts in two groups. Results Eighteen volunteers were successfully performed MRI scan of parotid gland. On 3D-FISP-FS sequence images, the parotid gland was showed slightly low signal intensity, muscle tissue was showed medium signal intensity, the vessels were showed slightly high or high signal, parotid segment of facial nerve was showed tortuous line-like high signal intensity, and parotid duct was showed curve high signal intensity, lymph nodes were showed kidney shaped, oval or spindle shaped high signal intensity structures. The subjective scores for head and neck coil and coil images were (2.0 ± 0.9) and (1.5 ± 0.7) respectively, and the difference was statistically significant (Z=-2.714, P=0.007), image quality of small coil group was better than that of head and neck coil group. The SIRN of the two groups was 1.7±0.8 and 2.1± 1.2 respectively, and the SIRD was 1.8±0.7 and 2.5±1.7 respectively, which showed a statistically significant difference between the two groups (t value was 2.978, 2.427 respectively, P value was 0.006, 0.031 respectively).All facial nerve trunks could be displayed by head and neck coil and small coil. On head and neck coil images, 25 sides of temporofacial truck, 15 sides of cervicofacial truck, 17 sides of temporofacial branches, 11 sides of cervicofacial branches, 16 sides of the parotid duct could be displayed. On small coil images, 30 sides of temporofacial truck, 28 sides of cervicofacial truck, 26 sides of temporofacial branches, 23 sides of cervicofacial branches, 27 sides of the parotid duct could be displayed, which showed a statistically significant difference (P<0.05). Conclusion Small surface coil performed better in parotid MR imaging with 3D-FISP-FS sequence than that of head and neck coil, which can simultaneous clearly display the trunk and branches of the intra-parotid facial nerves and parotid ducts.
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Objective We evaluate if supplementary grading system can refine patient selection and accurately predict neurological outcome in BAVM. Methods We retrospectively study 221 BAVM patients who were treated micro?surgically by our hospital. The score of pre and post operation mRS and relative clinical, radiology data were collected. Two different logistic models (Spetzler-Martin, Supplementary Spetzler-Martin grading model) were constructed to com?pare the area under ROC. Results Some factors are significant different between worse outcome patients and good out?come patients:Non-hemorrhagic presentations prior surgery, AVM bigger than 3cm, diffuse shape of AVM and the elder patients. Predictive accuracy was higher for the supplementary model (ROC area, 0.91), than the Spetzler-Martin model (ROC area, 0.774). So the predictive accuracy of supplementary model was significantly better than that of the Spet?zler-Martin model (P=0.0362). Conclusions Supplementary Spetzler-Martin model can improve preoperative risk pre?diction and subgroup the patients more efficiently. When the score less than 5(including 5) in supplementary Spet?zler-Martin patients seem to have lower risk relative to surgery.
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ObjectiveTo study the effects of oral administration of mannitol and intramuscular injection of anisodamine in magnetic resonance enteroclysis.Methods After complete intestinal cleaning,29 patients undergoing magnetic resonance enteroclysis were orally administered with 5% oral isotonic mannitol solution 2000 mL and treated with intramuscular injection of anisodamine before the operation.The adverse reactions were observed,the image quality was inspected and the dilatation of small bowel was detected.Results All of the patients lived through the magnetic resonance enteroclysis.Two patients contracted Crohn’s disease with mild nausea consciousness.Conclusion For magnetic resonance imaging,preoperative oral administration of 2.5% oral isotonic mannitol solution and intramuscular injection of anisodamine after complete intestinal cleaning is beneficial for fully expanding the small intestine,achieving quality imaging and therefore improving the diagnosis of small intestinal lesions.