Vertebrobasilar dolichoectasia to trigeminal neuralgia: case report.

Vertebrobasilar dolichoectasia (VBD) is a dilated arterial disease with a diameter ˃4.5 mm. Trigeminal neuralgia (TN) is chronic neuropathic pain. Through the diagnosis and treatment of this case we believe that there is a significant risk associated with the endovascular treatment of VBD. The development of post-operative complications caused some functional impairment to the patient, but the improvement in TN symptoms with this endovascular treatment was unexpected. This treatment procedure was considered to be possibly related to the alteration of the tortuous path of the vessels, changing their course, allowing the displacement of vascular compression in the trigeminal root entry zone, and possibly also altering the hemodynamics of the posterior circulation, improving the progression of ischemia and hypoxia-induced demyelination of the trigeminal nerve. Due to the low incidence of this disease, there are not enough large sample studies for systematic statistical analysis.

Deep medullary veins as an important imaging indicator of poor prognosis in acute ischemic stroke: a retrospective cohort survey.

Background: The deep medullary veins (DMVs), which constitute a component of the intracerebral venous circulation system and are part of intracerebral reperfusion mechanisms, have been suggested as a novel imaging marker for cerebral white matter hypersignal and cerebral small vessel disease based on their discontinuous and reduced visual representation. However, the correlation between the number and continuity of visible DMVs and the poor prognosis of acute ischemic stroke (AIS) remains undefined. Magnetic susceptibility-weighted imaging was applied in this study to assess the distribution and structural characteristics of DMVs in patients with AIS and to investigate its relationship with the poor prognosis of those with AIS. Methods: This retrospective study included 90 patients diagnosed with AIS in the middle cerebral artery region by the Neurology Department of Liaoning Provincial People's Hospital. Clinical, laboratory, and cranial magnetic resonance imaging data were collected. After the 3-month follow-up visit, patients were dichotomized into good (0-2 points) and poor (≥3 points) prognosis groups based on the modified Rankin Scale score, and the DMV imaging characteristics were evaluated using a 3-level visual rating scale. The association between DMV and AIS prognosis was determined through Mann-Whitney test and multivariate logistic regression analysis. Results: In univariate analysis, factors that were statistically significant between the different prognostic groups were DMV score (P=0.007), DMV symmetry (P=0.016), infarct size (P=0.029), and admission National Institutes of Health Stroke Scale (NIHSS) score (P<0.001). DMV score had a positive correlation with NIHSS score, (rs=0.209; P=0.048). Logistic regression analysis showed that the DMV score [odds ratio (OR), 1.356; 95% confidence interval (CI): 1.114-1.650; P=0.002], NIHSS score (OR, 1.280; 95% CI: 1.117-1.466; P<0.001), and fasting glucose (OR, 1.220; 95% CI: 1.023-1.456; P=0.027) were risk factors for poor prognosis in those with AIS. Conclusions: Discontinuity in DMV visualization was found to be associated with an unfavorable prognosis for patients AIS. The visual assessment of DMV through susceptibility-weighted imaging has the potential to predict AIS prognosis and furnish valuable insights for clinical treatment.

Association fiber tracts related to Broca's area: A comparative study based on diffusion spectrum imaging and fiber dissection.

Broca's area, made up of Brodmann areas (BA) 44 and 45 in the ventrolateral frontal region, is associated with language production and articulation. A comprehensive network analysis of Broca's area is necessary for understanding language function, which is still lacking. In this study, we attempted to investigate the association fiber tracts related to Broca's area using both diffusion spectrum imaging (DSI) and postmortem fiber dissection. DSI was performed on 10 healthy subjects and an atlas comprising the average data of 842 healthy subjects from the Human Connectome Project. Fiber dissection was implemented in 10 cerebral hemispheres of cadaver donors. The following five association fiber tracts related to Broca's area were identified: first, the distinct fasciculus of the inferior fronto-occipital fasciculus (IFOF), from Broca's area (BA44, BA45) and pars orbitalis (BA47) to the parietal and occipital lobes; second, the ventral superior longitudinal fasciculus (SLF-III), from the supramarginal gyrus (BA40) to the ventral precentral gyrus (PreG, BA6) and posterior Broca's area (BA44); third, the arcuate fascicle (AF), from the superior, middle, and inferior temporal gyrus (BA20, BA21, BA22) to Broca's area (BA44, BA45) and ventral PreG; fourth, the frontal aslant tract (FAT), from Broca's area (BA44, BA45) to the lateral superior frontal gyrus (SFG), medial SFG, and supplementary motor area (BA6, BA8, BA9); and fifth, the frontal longitudinal fasciculus (FLF), a novel intralobar frontal association fiber tract, from the anterior part of the middle frontal gyrus (MFG, BA46) and Broca's area (BA45) to the caudal MFG (BA8), caudal SFG, and dorsal PreG (BA6). Moreover, compared with the left FAT, the right FAT covered almost the entire inferior frontal gyrus (BA44, BA45, BA47). The cross validation between DSI and fiber dissection revealed a good consistence in the association fiber tracts of Broca's area. Combining DSI and fiber dissection, this study first identified five association fiber tracts related to Broca's area and characterized their structure and anatomy comprehensively. The frameworks provided key elements for functional research in Broca's area.

Clinical and Angiographic Outcomes of Endovascular Treatment for Ruptured Posterior Circulation Cerebral Aneurysms.

AIM: To report the angiographic and clinical results achieved in endovascular treatment of ruptured posterior circulation cerebral aneurysms over a 3-year period. MATERIAL AND METHODS: A retrospective analysis of 45 patients was performed between June 2008 and June 2011. Clinical follow-up was achieved in all patients, with a mean duration of 17 months. Angiographic follow-up was obtained in 88.9% of cases, with a mean duration of 7.2 months. RESULTS: A clinical improvement, or stable outcome was achieved in all patients. There was one case of re-bleeding as a periprocedural complication 2 days after incomplete stent-assisted coiling of a vertebral artery aneurysm. There was no death in our patients. In 40 of the 45 patients (88.9%), angiographic follow-up was obtained at a mean of 7.2 months (range, 1 to 24 months). Recurrences in 5 patients (12.5%) at 2 days, 3, 6, 8, and 13 months required re-treatment. CONCLUSION: Endovascular embolization is an attractive option for ruptured posterior circulation aneurysms with stable long-term outcome. This study confirmed that endovascular treatment is associated with low mobidity and mortality. However, re-canalization may be observed up to 2 years after the initial obliteration. Long-term follow-up with angiography is needed.

Transarterial ONYX Embolization of Intracranial Dural Arteriovenous Fistulas in Adults.

AIM: To present our experience on transarterial treatment of dural arteriovenous fistulas (DAVFs) with ONYX in adult patients. MATERIAL AND METHODS: Between March 2008 and November 2012, 27 adult patients with DAVFs treated by transarterial ONYX embolization were included. Clinical data, including hospital records, operative reports, and angiograms, were reviewed and analyzed. RESULTS: Complete obliteration of the fistula was achieved in 16/27 (59.3%) patients after 32 intra-arterial embolizations. One complication (3.7%) was transient hemiparesis. Follow-up imaging, which was available for 16 fistulas with angiographic cures, showed no evidence of recurrence. At mean 14.5 months follow-up, 26 patients (96.3%) had GOS score of 5 and 1 patient (3.7%) had GOS score of 3. CONCLUSION: Transarterial ONYX embolization has become the main treatment for adult intracranial DAVFs and is associated with high safety and efficacy.

Indocyanine green videoangiography in clipping of paraclinoid aneurysms.

AIM: To evaluate the use of indocyanine green (ICG) videoangiography in surgical clipping of paraclinoid aneurysms. MATERIAL AND METHODS: Intraoperative ICG videoangiography was used as a surgical adjunct in 60 patients with 65 paraclinoid aneurysms. The findings on ICG videoangiography were compared with postoperative imaging. RESULTS: All 65 paraclinoid aneurysms were clearly identified by intraoperative ICG videoangiography and obliteration was documented in each case. Findings on ICG videoangiography matched with postoperative angiography. CONCLUSION: ICG videoangiography is a useful adjunct to the surgical management of paraclinoid aneurysms.

Intraprocedural cerebral aneurysm rupture during endovascular coiling.

BACKGROUND: Intraprocedural aneurysm rupture is considered to be one of the most formidable complications of the endovascular treatment of cerebral aneurysms and is associated with high mortality. OBJECTIVE: To report the clinical outcomes of cerebral aneurysms that ruptured during endovascular coiling. PATIENTS AND METHODS: Over a period of six years, 559 endovascular embolizations were performed in 467 patients, with 507 cerebral aneurysms. Intraprocedural aneurysm rupture occurred in 14 cases (mean aneurysm size, 3.8 mm). Follow-up angiograms, at a minimum of three months post embolization, were available in 11 living patients. Acute and follow-up results were reviewed. RESULTS: The difference in the rates of aneurysm perforation during endovascular coiling between ruptured and unruptured aneurysms was significant (P < 0.05). There were three (21.4%) deaths related to this complication and three (21.4%) patients developed new deficits (modified Rankin Scale scores 1 to 2). Acute results of embolization were: complete occlusion in eight (57.1%), neck remnant in two (14.3%), and incomplete occlusion in four (28.6%) patients. Long-term follow-up results in 11 living patients were: major recanalization in one (9.1%), minor recanalization in one (9.1%), and stable occlusion in nine (81.8%). CONCLUSION: Intraprocedural aneurysm rupture frequently occurs in small aneurysms and appears to be associated with relatively high rates of mortality.

Endovascular embolization of very small cerebral aneurysms.

BACKGROUND: Very small cerebral aneurysms are considered to be one of the challenges for endovascular treatment, with difficulty for catheterization and high risk for intraoperative rupture. We report the treatment of very small (< 3-mm) cerebral aneurysms by coil embolization. MATERIALS AND METHODS: We performed a retrospective analysis of 11 consecutive patients with very small aneurysms treated by coil embolization in our institute between February 2007 and February 2009. RESULTS: Three-dimensional rotational angiography (3DRA) was most accurate in the detection of these aneurysms; 3DRA revealed the aneurysms in two patients in whom conventional angiography failed to demonstrate the aneurysms. The Hunt-Hess (HH) grade was grade 0 (unruptured aneurysm) in one patient and grade I in ten patients. Coil embolization was successfully performed in 11 patients. Complete (n = 8) or near complete (n = 3) immediate occlusion was obtained. One or three soft coils were used in all the patients with the shortest available length. Balloon assistance was used in one patient and stent assistance was used in seven patients. Although coil migration into the MCA was seen in one patient and intraoperative aneurismal rupture occurred in one patient, no untoward clinical complication was seen. Follow-up DSA in 11 patients demonstrated persistent occlusion (n = 9) or progressive thrombosis (n = 2) of the aneurysms. All the patients with available follow-up had a modified Rankin Score (mRS) of 0. CONCLUSION: HH grade 0 and I very small cerebral aneurysms can be treated by endovascular coil embolization. Use of short, soft coils and balloon/stent assistance is useful.

ERK phosphorylation in intact, adult brain by alpha(2)-adrenergic transactivation of EGF receptors.

Our previous work demonstrated dexmedetomidine-activated phosphorylation of extracellular regulated kinases 1 and 2 (ERK(1/2)) in primary cultures of mouse astrocytes and showed that it is evoked by alpha(2)-adrenoceptor-mediated transactivation of epidermal growth factor (EGF) receptors, a known response to activation of G(i/o)- or G(q)-coupled receptors [Li, B., Du, T., Li, H., Gu, L., Zhang, H., Huang, J., Hertz, L., Peng, L., 2008a. Signaling pathways for transactivation by dexmedetomidine of epidermal growth factor receptors in astrocytes and its paracrine effect on neurons. Br. J. Pharmacol. 154, 191-203]. Like most studies of transactivation, that study used cultured cells, raising the question whether a similar effect can be demonstrated in intact brain tissue and the brain in vivo. In the present study we have shown that (i) dexmedetomidine-mediated ERK(1/2) phosphorylation occurs in mouse brain slices with a similar concentration dependence as in cultured astrocytes (near-maximum effect at 50nM); (ii) intraperitoneal injection of dexmedetomidine (3microg/kg) in adult mice causes rapid phosphorylation of the EGF receptor (at Y845 and Y992) and of ERK(1/2) in the brain; (iii) both EGF receptor and ERK(1/2) phosphorylation are inhibited by intraventricular administration of (a) AG 1478, a specific inhibitor of the receptor-tyrosine kinase of the EGF receptor; (b) GM 6001, an inhibitor of metalloproteinase(s) required for release of EGF receptor agonists from membrane-bound precursors; or (c) heparin, neutralizing heparin-binding EGF (HB-EGF). Thus, in intact brain HB-EGF, known to be expressed in brain, may be the major EGF agonist released in response to stimulation of alpha(2)-adrenoceptors, the released agonist(s) activate(s) EGF receptors, and ERK(1/2) is phosphorylated as a conventional response to EGF receptor activation. Our previous paper (see above) showed that dexmedetomidine evokes no ERK(1/2) phosphorylation in cultured neurons, but neurons respond to astrocyte-conditioned medium (and to EGF) with ERK(1/2) phosphorylation. The present findings therefore suggest that EGF receptor transactivation in astrocytes in the mature brain in vivo is an important process in response to alpha(2)-adrenoceptor stimulation and may lead to phosphorylation of ERK(1/2) both in astrocytes themselves and in adjacent neurons.

Usefulness of diffusion/perfusion-weighted MRI in rat gliomas: correlation with histopathology.

RATIONALE AND OBJECTIVES: Diffusion/perfusion-weighted MRI (DWI/PWI) can provide additional useful information in the diagnosis of patients with brain gliomas in a noninvasive fashion. However, the exact role of these new techniques is still undergoing evaluation. Our hypothesis was that DWI and PWI could be useful for assessment of growth and vascularity of implanted C6 rat gliomas. MATERIALS AND METHODS: Thirty-six rats were implanted with C6 glioma cells intracerebrally. Between 1 and 4 weeks after implantation, 8-10 rats were imaged on a clinical, 1.5-T whole-body magnetic resonance system with T(1)-weighted imaging (T(1)WI), T(2)-weighted imaging, DWI, PWI, and postcontrast T(1)WI at each weekly time point. All tumors were examined histologically; tumor cellularity and microvascular density were counted. RESULTS: On DWIs, statistical differences of apparent diffusion coefficient values for both the tumoral core and peritumoral region were present comparing tumors of 3-4 weeks' growth with tumors of 1-2 weeks' growth. Apparent diffusion coefficient value of tumoral core was negatively correlated with tumor cellularity (r = -0.682, P < .01). Statistical difference of maximal regional cerebral blood volume of tumoral core was present comparing 2-4 weeks with both 1 week after implantation and contralateral white matter (P < .01). Native vessel dilation in regions of normal brain at the periphery of the tumors at 1 week after implantation was observed. Correlation between maximal regional cerebral blood volume of tumor core and microvascular density was present (r = 0.716, P < .01). CONCLUSION: DWI and PWI has potential to characterize C6 gliomas in rats, which is a promising model similar to human gliomas.