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8 October 2020, 3:14 pm
Piantino, J., Boespflug, E. L., Schwartz, D. L., Luther, M., Morales, A. M., Lin, A., Fossen, R. V., Silbert, L., Nagel, B. J.
BACKGROUND AND PURPOSE:

Perivascular spaces play a role in cerebral waste removal and neuroinflammation. Our aim was to provide data regarding the burden of MR imaging–visible perivascular spaces in white matter in healthy adolescents using an automated segmentation method and to establish relationships between common demographic characteristics and perivascular space burden.

MATERIALS AND METHODS:

One hundred eighteen 12- to 21-year-old subjects underwent T1- and T2-weighted 3T MR imaging as part of the National Consortium on Alcohol and Neurodevelopment in Adolescence. Perivascular spaces were identified in WM on T2-weighted imaging using a local heterogeneity approach coupled with morphologic constraints, and their spatial distribution and geometric characteristics were assessed.

RESULTS:

MR imaging–visible perivascular spaces were identified in all subjects (range, 16–287). Males had a significantly higher number of perivascular spaces than females: males, mean, 98.4 ± 50.5, versus females, 70.7 ± 36.1, (P < .01). Perivascular space burden was bilaterally symmetric (r > 0.4, P < .01), and perivascular spaces were more common in the frontal and parietal lobes than in the temporal and occipital lobes (P < .01). Age and pubertal status were not significantly associated with perivascular space burden.

CONCLUSIONS:

Despite a wide range of burden, perivascular spaces are present in all healthy adolescents. Perivascular space burden is higher in adolescent males than in females, regardless of age and pubertal status. In this population, perivascular spaces are highly symmetric. Although widely reported as a feature of the aging brain, awareness of the presence of perivascular spaces in a cohort of healthy adolescents provides the foundation for further research regarding the role of these structural variants in health and disease.


8 October 2020, 2:19 pm
Nael, K., Dagher, J. C., Downs, M. E., Fine, M. S., Brokaw, E., Millward, D.
BACKGROUND AND PURPOSE:

Developed using a rigorous mathematic framework, Maximum AmbiGuity distance for Phase Imaging (MAGPI) is a promising phase-imaging technique that provides optimal phase SNR and reduced susceptibility artifacts. We aimed to test the potential of MAGPI over routinely used SWI in the detection of traumatic cerebral microbleeds in athletes diagnosed with mild traumatic brain injury.

MATERIALS AND METHODS:

In this prospective study, 10 athletes (18–22 years of age, 3 women/7 men) diagnosed with mild traumatic brain injury were enrolled. Brain MRIs were performed using 3T MR imaging at 2 days, 2 weeks, and 2 months after head trauma. The imaging protocol included whole-brain T1 MPRAGE, T2 FLAIR, conventional SWI, and the MAGPI multiecho sequence. Phase images from MAGPI were put through a previously described SWI process to generate MAGPI-SWI. Conventional and MAGPI-SWI were assessed independently by a board-certified neuroradiologist for the presence of contusions and cerebral microbleeds. All participants had routine neuropsychological assessment and Visuo-Motor Tests.

RESULTS:

At initial assessment, 4 of the participants had visuo-motor performance indicative of mild traumatic brain injury, and 4 participants had a Post-Concussion Symptom Scale score of >21, a threshold that has been used to define moderate impairment. Cerebral microbleeds were identified in 6 participants on MAGPI-SWI, 4 of whom had evidence of concurrent contusions on FLAIR imaging. None of these cerebral microbleeds were identified confidently on conventional SWI due to substantial distortion and susceptibility artifacts.

CONCLUSIONS:

Optimal phase unwrapping with reduced susceptibility in MAGPI-SWI can clarify small microbleeds that can go undetected with routinely used conventional SWI.


1 October 2020, 2:23 pm
Hiramatsu, M., Sugiu, K., Hishikawa, T., Haruma, J., Takahashi, Y., Murai, S., Nishi, K., Yamaoka, Y., Shimazu, Y., Fujii, K., Kameda, M., Kurozumi, K., Date, I.
BACKGROUND AND PURPOSE:

Detailed arterial anatomy of the sphenoid ridge and olfactory groove meningiomas is complicated due to the fine angioarchitecture and anastomoses between each feeder. Herein, we present details of the arterial anatomy and the relationships of feeders in these lesions.

MATERIALS AND METHODS:

This study included 20 patients admitted to our department between April 2015 and March 2020. Conditions of subjects consisted of 16 sphenoid ridge meningiomas and 4 olfactory groove meningiomas. We mainly analyzed arterial anatomy using 3D rotational angiography and slab MIP images of these lesions. We also analyzed the anastomoses of each feeder.

RESULTS:

We found that 19 (95%), 15 (75%), and 15 (75%) lesions had feeders from the ophthalmic, internal carotid, and external carotid arteries, respectively. As feeders from the ophthalmic artery, recurrent meningeal arteries were involved in 18 lesions (90%). Fifteen lesions (75%) had anastomoses between each feeder.

CONCLUSIONS:

Most of the meningiomas in the sphenoid ridge and olfactory groove had feeders from the ophthalmic and internal carotid arteries. There were various anastomoses between each feeder. This is the first report to demonstrate the detailed arterial anatomy and frequency of recurrent branches from the ophthalmic artery and their anastomoses using detailed imaging techniques.


1 October 2020, 2:21 pm
Zamponi, J. O., Trivelato, F. P., Rezende, M. T. S., Freitas, R. K., de Castro-Afonso, L. H., Nakiri, G. S., Abud, T. G., Ulhoa, A. C., Abud, D. G.
BACKGROUND AND PURPOSE:

Treatment of dural arteriovenous fistulas can be performed by transarterial or transvenous accesses. For those fistulas located at a dural sinus wall, obliteration of the sinus might lead to a substantial risk of complications if the occluded sinus impairs normal venous drainage. For those fistulas with direct leptomeningeal venous drainage, navigation to reach the arteriovenous shunting point of a leptomeningeal vein is usually technically demanding. We report the outcomes of patients with dural AVFs treated by transarterial injection of liquid embolic agents assisted by transarterial double-lumen balloon catheters and/or transvenous balloon catheters.

MATERIALS AND METHODS:

This was a retrospective, 3-center study including patients with dural AVFs treated with a balloon-assisted technique in at least 1 treatment session. Angiographic follow-up was performed at 6 months. Clinical assessment was performed at admission and discharge and was reassessed at 30-day and 6-month follow-ups.

RESULTS:

Forty-one patients with 43 dural AVFs were treated. Thirty-four fistulas were located at a dural sinus wall. Treatment was performed using only a transarterial approach in 42 fistulas. Only 1 session was needed for complete obliteration of the fistula in 86% of the patients. Immediate complete angiographic occlusion was achieved in 39 fistulas. Of the 41 controlled fistulas, 40 (97.6%) were completely occluded at 6 months. Thirty-nine fistulas (95.1%) were cured without any report of major neurologic events or death during follow-up.

CONCLUSIONS:

Transarterial balloon-assisted treatment of dural AVFs with or without transvenous balloon protection was shown to be safe and effective.


1 October 2020, 2:16 pm
McDougall, C. C., Chan, L., Sachan, S., Guo, J., Sah, R. G., Menon, B. K., Demchuk, A. M., Hill, M. D., Forkert, N. D., dEsterre, C. D., Barber, P. A.
BACKGROUND AND PURPOSE:

Infarct core volume measurement using CTP (CT perfusion) is a mainstay paradigm for stroke treatment decision-making. Yet, there are several downfalls with cine CTP technology that can be overcome by adopting the simple perfusion reconstruction algorithm (SPIRAL) derived from multiphase CTA. We compare SPIRAL with CTP parameters for the prediction of 24-hour infarction.

MATERIALS AND METHODS:

Seventy-two patients had admission NCCT, multiphase CTA, CTP, and 24-hour DWI. All patients had successful/quality reperfusion. Patient-level and cohort-level receiver operator characteristic curves were generated to determine accuracy. A 10-fold cross-validation was performed on the cohort-level data. Infarct core volume was compared for SPIRAL, CTP–time-to-maximum, and final DWI by Bland-Altman analysis.

RESULTS:

When we compared the accuracy in patients with early and late reperfusion for cortical GM and WM, there was no significant difference at the patient level (0.83 versus 0.84, respectively), cohort level (0.82 versus 0.81, respectively), or the cross-validation (0.77 versus 0.74, respectively). In the patient-level receiver operating characteristic analysis, the SPIRAL map had a slightly higher, though nonsignificant (P < .05), average receiver operating characteristic area under the curve (cortical GM/WM, r = 0.82; basal ganglia = 0.79, respectively) than both the CTP–time-to-maximum (cortical GM/WM = 0.82; basal ganglia = 0.78, respectively) and CTP-CBF (cortical GM/WM = 0.74; basal ganglia = 0.78, respectively) parameter maps. The same relationship was observed at the cohort level. The Bland-Altman plot limits of agreement for SPIRAL and time-to-maximum infarct volume were similar compared with 24-hour DWI.

CONCLUSIONS:

We have shown that perfusion maps generated from a temporally sampled helical CTA are an accurate surrogate for infarct core.