Energy consumption in MRI: Determinants and management options

BACKGROUND

Energy consumption awareness is a known concern, and radiology departments have energy-intensive consuming machines. The means of energy consumption management in MRI scanners have yet to be evaluated.

PURPOSE

To measure the MRI energy consumption and to evaluate the means to reduce it.

MATERIALS AND METHODS

Data was retrieved for two MRI scanners through the hospital's automated energy consumption measurement software. After correlation with picture archiving and communication system (PACS) files, they were segmented by machine and mode (as follows: stand-by, idle and active) and analyzed. Active mode data for a specific brain MRI protocol have been isolated, and equivalent low energy consuming protocol was made. Both were performed on phantom and compared. Same protocol was performed on a phantom using 3.0T 16 and 32 head channels coils. Multiples sequences were acquired on phantom to evaluate power consumption.

RESULTS

Stand-by mode accounted for 60 % of machine time and 40 % of energy consumption, active mode accounted for 20 % machine time and 40 % energy consumption, idle mode for 20 % imachine time and 20 % consumption. DWI and TOF sequences were the most consuming in our brain-MRI protocol. The low energy consuming protocol allowed a saving of approximately 10 % of energy consumption, which amounted for 0.20€ for each examination. This difference was mainly due to an energy consumption reduction of the DWI sequence. There were no difference in consumption between a 3.0T 16 and 32 channels head coils. Sequence's active power and duration (especially considering slice thickness) have to be taken into account when trying to optimize energy consumption.

CONCLUSION

There are two key factors to consider when trying to reduce MRI scan energy consumption. Stand-by mode energy consumption has to be taken into account when choosing an MRI scan, as it can't be changed further on. Active mode energy consumption is dependent of the MRI protocols used, and can be reduced with sequences adaptation, which must take into account sequence's active power and duration, on top of image quality.

The Management of Persistent Distal Occlusions after Mechanical Thrombectomy and Thrombolysis: An Inter- and Intrarater Agreement Study

BACKGROUND AND PURPOSE

The best management of patients with persistent distal occlusion after mechanical thrombectomy with or without IV thrombolysis remains unknown. We sought to evaluate the variability and agreement in decision-making for persistent distal occlusions.

MATERIALS AND METHODS

A portfolio of 60 cases was sent to clinicians with varying backgrounds and experience. Responders were asked whether they considered conservative management or rescue therapy (stent retriever, aspiration, or intra-arterial thrombolytics) a treatment option as well as their willingness to enroll patients in a randomized trial. Agreement was assessed using κ statistics.

RESULTS

The electronic survey was answered by 31 physicians (8 vascular neurologists and 23 interventional neuroradiologists). Decisions for rescue therapies were more frequent (n = 1116/1860, 60%) than for conservative management (n = 744/1860, 40%; P < .001). Interrater agreement regarding the final management decision was "slight" (κ = 0.12; 95% CI, 0.09-0.14) and did not improve when subgroups of clinicians were studied according to background, experience, and specialty or when cases were grouped according to the level of occlusion. On delayed re-questioning, 23 of 29 respondents (79.3%) disagreed with themselves on at least 20% of cases. Respondents were willing to offer trial participation in 1295 of 1860 (69.6%) cases.

CONCLUSIONS

Individuals did not agree regarding the best management of patients with persistent distal occlusion after mechanical thrombectomy and IV thrombolysis. There is sufficient uncertainty to justify a dedicated randomized trial.

Rescue intracranial permanent stenting for refractory occlusion following thrombectomy: a propensity matched analysis

BACKGROUND

Rescue intracranial stenting (RIS) can be used in refractory large vessel occlusion (LVO) after mechanical thrombectomy (MT). We aimed to assess the safety and efficacy of RIS versus a propensity matched sample of patients with persistent LVO.

METHODS

We retrospectively analysed a multicenter retrospective pooled cohort of patients with anterior LVO (2015-2021) treated with MT, and identified patients with at least three passes and a modified Thrombolysis In Cerebral Infarction (mTICI) score of 0 to 2a. Propensity score matching was used to account for determinants of outcome in patients with or without RIS. The study outcomes included 3 months modified Rankin Scale (mRS) and symptomatic hemorrhagic transformation (HT).

RESULTS

420 patients with a refractory anterior occlusion were included, of which 101 were treated with RIS (mean age 69 years). Favorable outcome (mRS 0-2) was more frequent in patients with a patent stent at day 1 (53% vs 6%, P<0.001), which was independently associated with an early dual antiplatelet regimen (P<0.05). In the propensity matched sample, patients treated with RIS versus without RIS had similar rates of favorable outcomes (36.8% vs 30.3%, P=0.606). Patients with RIS showed a favorable shift in the overall mRS distributions (common adjusted OR 0.74, 95% CI 0.60 to 0.91, P=0.006). Symptomatic HT was marginally more frequent in the RIS group (9% vs 3%, P=0.07), and there was no difference in 3-month mortality.

CONCLUSION

In selected patients with a refractory intracranial occlusion despite at least three thrombectomy passes, RIS may be associated with an overall shift towards more favorable clinical outcome, and no significant increase in the odds of symptomatic HT or death.

Secondary Neurologic Deterioration After Moderate Traumatic Brain Injury: Development of a Multivariable Prediction Model and Proposition of a Simple Triage Score

BACKGROUND

Identifying patients at risk of secondary neurologic deterioration (SND) after moderate traumatic brain injury (moTBI) is a challenge, as such patients will need specific care. No simple scoring system has been evaluated to date. This study aimed to determine clinical and radiological factors associated with SND after moTBI and to propose a triage score.

METHODS

All adults admitted in our academic trauma center between January 2016 and January 2019 for moTBI (Glasgow Coma Scale [GCS] score, 9-13) were eligible. SND during the first week was defined either by a decrease in GCS score of >2 points from the admission GCS in the absence of pharmacologic sedation or by a deterioration in neurologic status associated with an intervention, such as mechanical ventilation, sedation, osmotherapy, transfer to the intensive care unit (ICU), or neurosurgical intervention (for intracranial mass lesions or depressed skull fracture). Clinical, biological, and radiological independent predictors of SND were identified by logistic regression (LR). An internal validation was performed using a bootstrap technique. A weighted score was defined based on beta (β) coefficients of the LR.

RESULTS

A total of 142 patients were included. Forty-six patients (32%) showed SND, and 14-day mortality rate was 18.4%. Independent variables associated with SND were age above 60 years (odds ratio [OR], 3.45 [95% confidence interval {CI}, 1.45-8.48]; P = .005), brain frontal contusion (OR, 3.22 [95% CI, 1.31-8.49]; P = .01), prehospital or admission arterial hypotension (OR, 4.86 [95% CI, 2.03-12.60]; P = .006), and a Marshall computed tomography (CT) score of 6 (OR, 3.25 [95% CI, 1.31-8.20]; P = .01). The SND score was defined with a range from 0 to 10. The score included the following variables: age >60 years (3 points), prehospital or admission arterial hypotension (3 points), frontal contusion (2 points), and Marshall CT score of 6 (2 points). The score was able to detect patients at risk of SND, with an area under the receiver operating characteristic curve (AUC) of 0.73 (95% CI, 0.65-0.82). A score of 3 had a sensitivity of 85%, a specificity of 50%, a VPN of 87%, and a VPP of 44 % to predict SND.

CONCLUSIONS

In this study, we demonstrate that moTBI patients have a significant risk of SND. A simple weighted score at hospital admission could be able to detect patients at risk of SND. The use of the score may enable optimization of care resources for these patients.

Assessment of using ultrasonography to teach abdominal and cervical anatomy in French medical curricula

PURPOSE

The objective of this work was to assess, in a quantitative and qualitative way, the teaching of cervical and abdominal anatomy via ultrasound for medical students.

METHODS

For several years, tutorials on the study of anatomy through use of ultrasound on the living organism have been given at the Medical School of Brest. These sessions have focused on cervical anatomy and abdominal anatomy. Students were invited to quantitatively assess these lessons by taking two tests containing questions on both cervical and abdominal anatomy and ultrasound technique: a pre-test administered at the beginning of the year and a post-test at the end of the year. In addition, a qualitative assessment was carried out at the end of the year. Ten statements were presented, and students were asked to indicate their agreement or disagreement to a four-point Likert scale.

RESULTS

One hundred and twelve students answered all the questions on the pre-test with an average of 13.4 correct answers out of 20. Forty-eight students answered all the questions on the post-test with an average of 14.6/20. Twenty-six students who benefited from the courses gave positive feedback about the workshops on the qualitative assessment at the end of the year (median scores >  = 3/4).

CONCLUSION

The results of this work suggest that the use of ultrasound makes a positive contribution to the teaching of anatomy. The students interviewed think this type of tutorial should be an integral part of the anatomy curriculum at our university. In addition, this type of instruction can serve to introduce the use of ultrasound itself in a practical learning setting.

Endovascular Management of Brain Arteriovenous Malformations

Due to the risk of cerebral hemorrhage, and its related morbidity-mortality, brain arteriovenous malformations (bAVMs) are a rare and potentially life-threatening disease. Despite this, there is only one randomized controlled trial on bAVM management, A Randomized trial of Unruptured Brain Arteriovenous malformations (ARUBA). The results of the ARUBA trial favor a noninterventional approach in the case of an unruptured bAVM; however, implementation of these findings is challenging in daily practice. Instead, management of bAVM relies on multidisciplinary discussions that lead to patient-specific strategies based on patient preferences, local expertise, and experience in referral centers. Considering the diverse patterns of presentation and numerous treatment modalities, implementing standardized guidelines in this context proves challenging, notwithstanding the recommendations or expert opinions offered. Endovascular treatment (EVT) of bAVM can be curative, or can serve as an adjunct treatment prior to surgery or radiosurgery ("pre-EVT"). EVT practice is in constant evolution (i.e., venous approach, combination with surgery during the same anesthesia, etc.). Liquid embolic agents such as ethylene vinyl alcohol (EVOH) copolymer and cyanoacrylates (CYA), and their method of injection to increase bAVM occlusion have also benefited from technical evolutions such as the use of adjunctive flow arrest techniques (mini balloons, pressure cooker technique, and multiple catheters). Further research is necessary to evaluate the advantages and disadvantages of EVT for bAVM.

Antithrombotic therapies for neurointerventional surgery: a 2021 French comprehensive national survey

BACKGROUND

Neurointerventionists lack guidelines for the use of antithrombotic therapies in their clinical practice; consequently, there is likely to be significant heterogeneity in antithrombotic use between centers. Through a nationwide survey, we aimed to obtain an exhaustive cross-sectional overview of antithrombotic use in neurointerventional procedures in France.

METHODS

In April 2021, French neurointerventional surgery centers were invited to participate in a nationwide 51-question survey disseminated through an active trainee-led research collaborative network (the JENI-RC).

RESULTS

All 40 centers answered the survey. Fifty-one percent of centers reported using ticagrelor and 43% used clopidogrel as premedication before intracranial stenting. For flow diversion treatment, dual antiplatelet therapy was maintained for 3 or 6 months in 39% and 53% of centers, respectively, and aspirin was prescribed for 12 months or more than 12 months in 63% and 26% of centers, respectively. For unruptured aneurysms, the most common heparin bolus dose was 50 IU/kg (59%), and only 35% of centers monitored heparin activity for dose adjustment. Tirofiban was used in 64% of centers to treat thromboembolic complications. Fifteen percent of these comprehensive stroke centers reported using tenecteplase to treat acute ischemic strokes. Cangrelor appeared as an emergent drug in specific indications.

CONCLUSION

This nationwide survey highlights the important heterogeneity in clinical practices across centers. There is a pressing need for trials and guidelines to further evaluate and harmonize antithrombotic regimens in the neurointerventional field.

Stent-Assisted Coiling in the Treatment of Unruptured Intracranial Aneurysms: A Randomized Clinical Trial

BACKGROUND AND PURPOSE

Stent-assisted coiling may improve angiographic results of endovascular treatment of unruptured intracranial aneurysms compared with coiling alone, but this has never been shown in a randomized trial.

MATERIALS AND METHODS

The Stenting in the Treatment of Aneurysm Trial was an investigator-led, parallel, randomized (1:1) trial conducted in 4 university hospitals. Patients with intracranial aneurysms at risk of recurrence, defined as large aneurysms (≥10 mm), postcoiling recurrent aneurysms, or small aneurysms with a wide neck (≥4 mm), were randomly allocated to stent-assisted coiling or coiling alone. The composite primary efficacy outcome was "treatment failure," defined as initial failure to treat the aneurysm; aneurysm rupture or retreatment during follow-up; death or dependency (mRS > 2); or an angiographic residual aneurysm adjudicated by an independent core laboratory at 12 months. The primary hypothesis (revised for slow accrual) was that stent-assisted coiling would decrease treatment failures from 33% to 15%, requiring 200 patients. Primary analyses were intent to treat.

RESULTS

Of 205 patients recruited between 2011 and 2021, ninety-four were allocated to stent-assisted coiling and 111 to coiling alone. The primary outcome, ascertainable in 203 patients, was reached in 28/93 patients allocated to stent-assisted coiling (30.1%; 95% CI, 21.2%-40.6%) compared with 30/110 (27.3%; 95% CI, 19.4%-36.7%) allocated to coiling alone (relative risk = 1.10; 95% CI, 0.7-1.7; P  = .66). Poor clinical outcomes (mRS >2) occurred in 8/94 patients allocated to stent-assisted coiling (8.5%; 95% CI, 4.0%-16.6%) compared with 6/111 (5.4%; 95% CI, 2.2%-11.9%) allocated to coiling alone (relative risk = 1.6; 95% CI, 0.6%-4.4%; P  = .38).

CONCLUSIONS

The STAT trial did not show stent-assisted coiling to be superior to coiling alone for wide-neck, large, or recurrent unruptured aneurysms.

Angioplasty, stenting, or both - rescue maneuvers and reperfusion after endovascular therapy for intracranial atherosclerosis-related occlusion

PURPOSE

Data concerning reperfusion strategies of intracranial atherosclerosis-related occlusion (ICARO) and clinico-angiographic outcomes remain scarce, particularly in Caucasians. We aim to compare the reperfusion rate and functional outcome between reperfusion strategies in the setting of the ICARO.

METHODS

Retrospective analysis of prospectively maintained endovascular thrombectomy (EVT) registries at three high-volume stroke centers were retrospectively analyzed for consecutive ICARO patients from January 2015 to December 2019. We defined ICARO as any fixed high-degree (> 70%) focal narrowing or stenosis of any degree with a perpetual tendency for reocclusion. We categorized reperfusion strategies into four groups: EVT [group 1], balloon angioplasty [(BAp), group 2], placement of self-expandable stents [(SES), group 3], and BAp combined with implantation of SES; or direct placement of balloon mounted stents (BMS) [(BAp-SES/BMS), group 4]. We evaluated the association with the successful reperfusion [mTICI 2b - 3] and favorable outcome [mRS 0-2] with logistic regression analysis.

RESULTS

Out of 2550 EVT, 124 patients (median age, 70 (61-80) years; 76 men) with ICARO and 130 reperfusion attempts [36 EVT, 38 BAp, 17 SES, and 39 BAp + SES/BMS] were analyzed. SES implantation showed the highest frequency of post-procedural symptomatic intracranial hemorrhage [(18%, 3/17), p = .03]; however, we observed no significant differences in the mortality rate. Overall, we achieved successful reperfusion in 71% (92/130) and favorable outcomes in 42% (52/124) of the patients. BAp + SES/BMS was the only independent predictor of the final successful reperfusion [aOR, 4.488 (95% CI, 1.364-14.773); p = .01], which was significantly associated with the 90-day favorable outcome [aOR, 10.837 (95% CI, 3.609-32.541); p =  < .001] after adjustment for confounding variables between the reperfusion strategies.

CONCLUSION

Among patients with ICARO, the rescue angioplasty stenting effectively contributed to higher odds of successful reperfusion with no increased risk for intracranial hemorrhage.

Complete recanalization predicts favorable outcome in patients with distal M2-M3 middle cerebral artery occlusions following endovascular thrombectomy

BACKGROUND

- scanty articles illustrate the prognostic factors for favorable outcome after endovascular thrombectomy (EVT) in distal vessel occlusion (DMVO). Moreover, the current literature is diversified; conglomerating both primary, secondary, and anterior, posterior circulations embolic strokes in the same shell.

PURPOSE

to identify the association between complete reperfusion and favorable outcome following EVT for DMVO in the middle cerebral artery (MCA) territory.

METHODS

-we performed a retrospective analysis of prospectively maintained EVT registries at two comprehensive stroke centers between January 2015 and December 2019 for consecutive stroke patients with MCA-DMVO. DMVO was defined as an occlusion of distal M2 and M3 segments of the MCA. Only patients with primary isolated occlusions were included. A multivariate logistic regression was utilized to identify clinical and procedural-related factors associated with the 90-day favorable clinical outcome [defined as modified Rankin score (mRS) 0-2] after EVT.

RESULTS

-Out of 1823 within the registries; 66 patients (median age was 72 (60-78) and 59% were males) with primary isolated DMVO of the MCA were eligible for inclusion in the current study. Complete reperfusion was achieved in 56% (37/66) of the patients with no difference among the reperfusion strategies while the favorable outcome was observed in 68% (45/66). In the multivariate analysis, final complete reperfusion [modified Thrombolysis In Cerebral Infarction (mTICI) score 2c-3] was significantly associated with favorable outcome [aOR=7.69; (95% CI 1.73-34.17); p=.01], while higher baseline NIHSS score [aOR=0.82; (95% CI 0.69-0.98); p=.03] and increased imaging to puncture interval [aOR=0.99; (95% CI 0.98, 1.00); p=.01] decreased the probability of the favorable outcome.

CONCLUSION

according to our results, complete reperfusion was the most significant predictor of the favorable outcome, while higher baseline NIHSS and longer imaging to puncture interval decreased the probability of the favorable outcome.

Frontline thrombectomy strategy and outcome in acute basilar artery occlusion

BACKGROUND

Novel thrombectomy strategies emanate expeditiously day-by-day counting on access system, clot retriever device, proximity to and integration with the thrombus, and microcatheter disengagement. Nonetheless, the relationship between native thrombectomy strategies and revascularization success remains to be evaluated in basilar artery occlusion (BAO).

PURPOSE

To compare the safety and efficacy profile of key frontline thrombectomy strategies in BAO.

METHODS

Retrospective analyses of prospectively maintained stroke registries at two comprehensive stroke centers were performed between January 2015 and December 2019. Patients with BAO selected after MR imaging were categorized into three groups based on the frontline thrombectomy strategy (contact aspiration (CA), stent retriever (SR), or combined (SR+CA)). Patients who experienced failure of clot retrieval followed by an interchanging strategy were categorized as a fourth (switch) group. Clinicoradiological features and procedural variables were compared. The primary outcome measure was the rate of complete revascularization (modified Thrombolysis in Cerebral Infarction (mTICI) grade 2c-3). Favorable outcome was defined as a 90 day modified Rankin Scale score of 0-2.

RESULTS

Of 1823 patients, we included 128 (33 underwent CA, 35 SR, 35 SR +CA, and 25 switch techniques). Complete revascularization was achieved in 83/140 (59%) primarily analyzed patients. SR +CA was associated with higher odds of complete revascularization (adjusted OR 3.04, 95% CI 1.077 to 8.593, p=0.04) which was an independent predictor of favorable outcome (adjusted OR 2.73. 95% CI 1.152 to 6.458, p=0.02). No significant differences were observed for symptomatic intracranial hemorrhage, functional outcome, or mortality rate.

CONCLUSION

Among BAO patients, the combined technique effectively contributed to complete revascularization that showed a 90 day favorable outcome with an equivalent complication rate after thrombectomy.

Parent artery stenting as a rescue management for stretched coils during cerebral aneurysms embolization: Report of three cases and review of literature

BACKGROUND

Displacement of a stretched coil into the parent artery during intracranial aneurysm coiling is a challenging situation where the risk of acute intravascular thrombosis might be a life-threatening condition. The usual way of management is coil snaring, yet in some cases, it might not be feasible to retrieve the coil. Parent artery rescue stenting had already been described as a way of management in acutely thrombosed parent arteries during aneurysm coiling.

CASE REPORTS

We present three cases with an inadvertent displacement of the unraveled coils into the parent artery for which rescue stenting was carried out to crush the coil against the vessel wall aiming to eliminate its thrombogenic effect. Our preliminary experience is that rescue stenting of the parent artery for stretched coil could be a convenient effective option particularly in case of failed/risky snaring with no notable immediate or long-term complications.

REVIEW AND DISCUSSION

We review the reported cases of stretched coils with or without further unraveling and fracture and discuss the possible consequences, salvage methods, and clinical outcomes. Neurointerventionists should be aware of this complication and get acquainted with bailout strategies.

Endovascular treatment of brain arteriovenous malformations: clinical outcomes of patients included in the registry of a pragmatic randomized trial

OBJECTIVE

The role of endovascular treatment in the management of patients with brain arteriovenous malformations (AVMs) remains uncertain. AVM embolization can be offered as stand-alone curative therapy or prior to surgery or stereotactic radiosurgery (SRS) (pre-embolization). The Treatment of Brain AVMs Study (TOBAS) is an all-inclusive pragmatic study that comprises two randomized trials and multiple registries.

METHODS

Results from the TOBAS curative and pre-embolization registries are reported. The primary outcome for this report is death or dependency (modified Rankin Scale [mRS] score > 2) at last follow-up. Secondary outcomes include angiographic results, perioperative serious adverse events (SAEs), and permanent treatment-related complications leading to an mRS score > 2.

RESULTS

From June 2014 to May 2021, 1010 patients were recruited in TOBAS. Embolization was chosen as the primary curative treatment for 116 patients and pre-embolization prior to surgery or SRS for 92 patients. Clinical and angiographic outcomes were available in 106 (91%) of 116 and 77 (84%) of 92 patients, respectively. In the curative embolization registry, 70% of AVMs were ruptured, and 62% were low-grade AVMs (Spetzler-Martin grade I or II), while the pre-embolization registry had 70% ruptured AVMs and 58% low-grade AVMs. The primary outcome of death or disability (mRS score > 2) occurred in 15 (14%, 95% CI 8%–22%) of the 106 patients in the curative embolization registry (4 [12%, 95% CI 5%–28%] of 32 unruptured AVMs and 11 [15%, 95% CI 8%–25%] of 74 ruptured AVMs) and 9 (12%, 95% CI 6%–21%) of the 77 patients in the pre-embolization registry (4 [17%, 95% CI 7%–37%] of 23 unruptured AVMs and 5 [9%, 95% CI 4%–20%] of 54 ruptured AVMs) at 2 years. Embolization alone was confirmed to occlude the AVM in 32 (30%, 95% CI 21%–40%) of the 106 curative attempts and in 9 (12%, 95% CI 6%–21%) of 77 patients in the pre-embolization registry. SAEs occurred in 28 of the 106 attempted curative patients (26%, 95% CI 18%–35%, including 21 new symptomatic hemorrhages [20%, 95% CI 13%–29%]). Five of the new hemorrhages were in previously unruptured AVMs (n = 32; 16%, 95% CI 5%–33%). Of the 77 pre-embolization patients, 18 had SAEs (23%, 95% CI 15%–34%), including 12 new symptomatic hemorrhages [16%, 95% CI 9%–26%]). Three of the hemorrhages were in previously unruptured AVMs (3/23; 13%, 95% CI 3%–34%).

CONCLUSIONS

Embolization as a curative treatment for brain AVMs was often incomplete. Hemorrhagic complications were frequent, even when the specified intent was pre-embolization before surgery or SRS. Because the role of endovascular treatment remains uncertain, it should preferably, when possible, be offered in the context of a randomized trial.

Surgical or Endovascular Treatment of MCA Aneurysms: An Agreement Study

BACKGROUND AND PURPOSE

MCA aneurysms are still commonly clipped surgically despite the recent development of a number of endovascular tools and techniques. We measured clinical uncertainty by studying the reliability of decisions made for patients with middle cerebral artery (MCA) aneurysms.

MATERIALS AND METHODS

A portfolio of 60 MCA aneurysms was presented to surgical and endovascular specialists who were asked whether they considered surgery or endovascular treatment to be an option, whether they would consider recruitment of the patient in a randomized trial, and whether they would provide their final management recommendation. Agreement was studied using κ statistics. Intrarater reliability was assessed with the same, permuted portfolio of cases of MCA aneurysm sent to the same specialists 1 month later.

RESULTS

Surgical management was the preferred option for neurosurgeons (n = 844/1320; [64%] responses/22 raters), while endovascular treatment was more commonly chosen by interventional neuroradiologists (1149/1500 [76.6%] responses/25 raters). Interrater agreement was only "slight" for all cases and all judges (κ = 0.094; 95% CI, 0.068-0.130). Agreement was no better within specialties or with more experience. On delayed requestioning, 11 of 35 raters (31%) disagreed with themselves on at least 20% of cases. Surgical management and endovascular treatment were always judged to be a treatment option, for all patients. Trial participation was offered to patients 65% of the time.

CONCLUSIONS

Individual clinicians did not agree regarding the best management of patients with MCA aneurysms. A randomized trial comparing endovascular with surgical management of patients with MCA aneurysms is in order.

Prospective assessment of aneurysmal rupture risk scores in patients with subarachnoid hemorrhage: a multicentric cohort

PURPOSE

The natural evolution of unruptured intracranial aneurysms (UIA) is indeed difficult to predict at the individual level.

OBJECTIVE

In a large prospective multicentric European cohort, we aimed to evaluate whether the PHASES, UCAS, and ELPASS scores in patients with aneurysmal subarachnoid hemorrhage would have predicted a high risk of aneurysmal rupture or growth.

METHODS

Academic centers treating patients with intracranial aneurysms were invited to prospectively collect de-identified data from all patients admitted at their institution for a subarachnoid hemorrhage-related to intracranial aneurysmal rupture between January 1 and March 31, 2021 through a trainee-led research collaborative network. Each responding center was provided with an electronic case record form (CRF) which collected all the elements of the PHASES, ELAPSS, and UCAS scores.

RESULTS

A total of 319 patients with aneurysmal subarachnoid hemorrhage were included at 17 centers during a 3-month period. One hundred eighty-three aneurysms (57%) were less than 7 mm. The majority of aneurysms were located on the anterior communicating artery (n = 131, 41%). One hundred eighty-four patients (57%), 103 patients (32%), and 58 (18%) were classified as having a low risk of rupture or growth, according to the PHASES, UCAS, and ELAPSS scores, respectively.

CONCLUSION

In a prospective study of European patients with aneurysmal subarachnoid hemorrhage, we showed that 3 common risk-assessment tools designed for patients with unruptured intracranial aneurysms would have not identified most patients to be at high or intermediate risk for rupture, questioning their use for decision-making in the setting of unruptured aneurysms.

Adenoid cystic carcinoma of jugular foramen

Adenoid cystic carcinoma is a slowly growing malignant tumor with high local recurrence, perineural and vascular invasion. This tumor might arise from the glands of upper respiratory tract and oral cavity (eg, salivary or serous or mucous). Here we report the case of a 65-year-old woman who was referred to our unit for left retro-auricular radiating pain with trigger points and frontal headache since 6 months. There was no involvement of cranial nerves. Imaging screening using MRI, Positron emission tomography with 2-[fluorine-18] fluoro-2-deoxy-D-glucose, Gallium-68 DOTA-Phe1-Tyr3-Octreotide (68Ga DOTATOC) Positron emission tomography-CT suggested a suspicion of schwannoma or paraganglioma of the jugular foramen. However, the CT-guided biopsy revealed presence of adenoid cystic carcinoma. These warrants performing mandatory histological analysis combined with imaging screening suspicion of schwannoma or paraganglioma.

Benefit of mechanical thrombectomy in acute ischemic stroke related to calcified cerebral embolus

PURPOSE

Mechanical thrombectomies (MT) in patients with large vessel occlusion (LVO) related to calcified cerebral embolus (CCE) have been reported, through small case series, being associated with low reperfusion rate and worse outcome, compared to regular MT. The purpose of the MASC (Mechanical Thrombectomy in Acute Ischemic Stroke Related to Calcified Cerebral Embolus) study was to evaluate the incidence of CCEs treated by MT and the effectiveness of MT in this indication.

METHODS

The MASC study is a retrospective multicentric (n = 37) national study gathering the cases of adult patients who underwent MT for acute ischemic stroke with LVO related to a CCE in France from January 2015 to November 2019. Reperfusion rate (mTICI ≥ 2B), complication rate and 90-day mRS were systematically collected. We then conducted a systematic review by searching for articles in PubMed, Cochrane Library, Embase and Google Scholar from January 2015 to March 2020. A meta-analysis was performed to estimate clinical outcome at 90 days, reperfusion rate and complications.

RESULTS

We gathered data from 35 patients. Reperfusion was obtained in 57% of the cases. Good clinical outcome was observed in 28% of the patients. The meta-analysis retrieved 136 patients. Reperfusion and good clinical outcome were obtained in 50% and 29% of the cases, respectively.

CONCLUSION

The MASC study found worse angiographic and clinical outcomes compared to regular thrombectomies. Individual patient-based meta-analysis including the MASC findings shows a 50% reperfusion rate and a 29% of good clinical outcome.

Model-Based Iterative Reconstruction (MBIR) for ASPECT Scoring in Acute Stroke Patients Selection: Comparison to rCBV and Follow-Up Imaging

Background: To compare a model-based iterative reconstruction (MBIR) versus a hybrid iterative reconstruction (HIR) for initial and final Alberta Stroke Program Early Ct Score (ASPECT) scoring in acute ischemic stroke (AIS). We hypothesized that MBIR designed for brain computed tomography (CT) could perform better than HIR for ASPECT scoring. Methods: Among patients who had undergone CT perfusion for AIS between April 2018 and October 2019 with a follow-up imaging within 7 days, we designed a cohort of representative ASPECTS. Two readers assessed regional-cerebral-blood-volume-ASPECT (rCBV-ASPECTS) on the initial exam and final-ASPECTS on the follow-up non-contrast-CT (NCCT) in consensus. Four readers performed independently MBIR and HIR ASPECT scoring on baseline NCCT. Results: In total, 294 hemispheres from 147 participants (average age of 69.59 ± 15.63 SD) were analyzed. Overall raters’ agreement between rCBV-map and MBIR and HIR ranged from moderate to moderate (κ = 0.54 to κ = 0.57) with HIR and moderate to substantial (κ = 0.52 to κ = 0.74) with MBIR. Overall raters’ agreement between follow-up imaging and HIR/MBIR ranged from moderate to moderate (κ = 0.55 to κ = 0.59) with HIR and moderate to almost perfect (κ = 0.48 to κ = 0.82) with MBIR. Conclusions: ASPECT scoring with MBIR more closely matched with initial and final infarct extent than classical HIR NCCT reconstruction.

Safety and Efficacy of Cangrelor Among Three Antiplatelet Regimens During Stent-Assisted Endovascular Treatment of Unruptured Intracranial Aneurysm: A Single-Center Retrospective Study

Introduction

Thromboembolic events represent the most frequent complications of endovascular treatment of unruptured intracranial aneurysm using stent-assisted coilling or flow diverter stents. Dual antiplatelet therapy has become the standard to prevent these but remains unstandardized. We present here a single center experience of 3 standardized antiplatelet regimens during brain aneurysm treatment, while emphasizing the use of the Cangrelor.

Method

We retrospectively reviewed data from patients treated using stent-assisted coilling or flow diverter stents from 2016 to 2021. We collected and compared safety and efficacy data within 6 months of three groups of patients corresponding to three antiplatelet standardized regimens: group T with Ticagrelor, with preprocedural preparation; group E with Eptifibatide, injected during procedure; group C with Cangrelor, injected during procedure.

Results

Data of 112 patients were analyzed and 76 belonged to group T, 21 to group E, and 15 to group C. Eleven events over the 14 recorded were adjudicated to be related to antiplatelets, their repartition did not differ between the 3 groups (p = 0.43). All symptomatic events (N = 8) were not distributed significantly differently between the 3 groups (p = 0.11) and asymptomatic events were also balanced (p = 1.00). Of these, 6 subjects had a change in the mRS score at 3–6 months. Thrombo-embolic events represented the most encountered events in the sample: 2 acute ischemic strokes were recorded in group E and 1 in group T; 1 transient ischemic stroke was noted in group E; 4 silent infarcts were found on control MRI (2 belonged to group T, 1 to group E and 1 to group C). Among 3 intracranial bleeding events, 1 was symptomatic in group C, 2 were asymptomatic in group T. On the control evaluation performed at 6 months, there was no significant difference on aneurysmal occlusion (p = 0.67).

Conclusion

This single-center retrospective study compared 3 antiplatelet regimens, finding no significant difference in the safety and efficacy in the context of endovascular treatments of unruptured aneurysm using stent or flow diverters. This study adds data for the Cangrelor use and suggests its usefulness in the field of neuro-endovascular intervention. Randomized controlled studies are warranted to confirm these results.

Carotid artery direct access for mechanical thrombectomy: the Carotid Artery Puncture Evaluation (CARE) study

BACKGROUND

In acute ischemic stroke due to anterior large vessel occlusion (AIS-LVO), accessing the target occluded vessel for mechanical thrombectomy (MT) is sometimes impossible through the femoral approach. We aimed to evaluate the safety and efficacy of direct carotid artery puncture (DCP) for MT in patients with failed alternative vascular access.

METHODS

We retrospectively analyzed data from 45 stroke centers in France, Switzerland and Germany through two research networks from January 2015 to July 2019. We collected physician-centered data on DCP practices and baseline characteristics, procedural variables and clinical outcome after DCP. Uni- and multivariable models were conducted to assess risk factors for complications.

RESULTS

From January 2015 to July 2019, 28 149 MT were performed, of which 108 (0.39%) resulted in DCP due to unsuccessful vascular access. After DCP, 77 patients (71.3%) had successful reperfusion (modified Thrombolysis In Cerebral Infarction (mTICI) score ≥2b) and 28 (25.9%) were independent (modified Rankin Scale (mRS) score 0-2) at 3 months. 20 complications (18.5%) attributed to DCP occurred, all of them during or within 1 hour of the procedure. Complications led to extension of the intubation time in the intensive care unit in 7 patients (6.4%) and resulted in death in 3 (2.8%). The absence of use of a hemostatic closure device was associated with a higher complication risk (OR 3.04, 95% CI 1.03 to 8.97; p=0043).

CONCLUSION

In this large multicentric study, DCP was scantly performed for vascular access to perform MT (0.39%) in patients with AIS-LVO and had a high rate of complications (18.5%). Our results provide arguments for not closing the cervical access by manual compression after MT.

The Combination of Stent and Antiplatelet Therapy May Be Responsible of Parenchymal Magnetic Susceptibility Artifacts after Endovascular Procedure

The aim was to assess the occurrence of magnetic susceptibility artifacts (MSA) following endovascular treatment of intracranial aneurysm by stent using susceptibility weighted imaging (SWI). Imaging and clinical data of 46 patients who underwent stent placement in the case of intracranial aneurysm endovascular treatment (S-Group) were retrospectively analyzed and compared to a control group (C-Group) in which 46 patients had coiling alone. The mean number of MSA was higher in the S-group than in the C-group on postprocedural SWI sequence (8.76, 95%CI [5.76; 11.76] vs. 0.78 [0.32; 1.25], respectively, p < 0.001) with a higher frequency of the appearance of MSA also in the S-group (78.26% vs. 21.74% in the C-group, p < 0.001). In the S-group, in the vascular territory of the treated artery, there was a higher number of MSA than in other vascular territories (mean of 5.18 [3.43; 6.92] vs. 3.08 [1.79; 4.36], p = 0.001). An odds ratio (OR) of 20.98 [5.24; 83.95] suggested a higher proportion of onset of MSA in the S-group than in the C-group (p < 0.001). The appearance of MSA after a treatment by stenting for intracranial aneurysm in patients under antiplatelet therapy was common, particularly in the treated artery territory.

Comparing N-hexyl cyanoacrylate (Magic Glue) and N-butyl cyanoacrylate (NBCA) for neurovascular embolization using the pressure cooker technique: An experimental study in swine

BACKGROUND

The pressure cooker (PC) technique uses a second microcatheter to produce a proximal occlusion to prevent the reflux of liquid embolic agent (LEA) injected through a more distal microcatheter, and can be used to treat arteriovenous malformations and dural arteriovenous fistulae. The liquid embolic Magic Glue (MG) (N-hexyl cyanoacrylate (NHCA)) has been introduced as an alternative to N-butyl cyanoacrylate (NBCA). Our goals were to compare the extent of embolization of rete mirabile with or without the PC technique using NBCA or MG, and to compare the proximal occlusions obtained with MG or NBCA while using the PC technique in a renal arterial model.

METHODS

Rete mirabile were embolized with (n = 4) and without (n = 4) the PC technique, using MG (n = 4) or NBCA (n = 4). A renal arterial model was then used to study the characteristics of the MG plug (n = 10) used for the PC technique, and resistance to catheter withdrawal as compared to NBCA (n = 4). Specimens were analyzed macro- and microscopically and compared to angiographic results.

RESULTS

Extent of rete embolization with CYA agents was not significantly greater when using the PC technique. Results were similar with both types of cyanoacrylate (p = 0.657). The force necessary to withdraw the microcatheter was less with MG than with NBCA (p = 0.035).

CONCLUSION

MG was similar to NBCA in extent of rete embolization. Less traction force was necessary to withdraw trapped non-detachable microcatheters using MG compared to NBCA.

Mapping the medullar adiposity of lumbar spine in MRI: A feasibility study

PURPOSE

The bone medullar adiposity is a marker of bone quality to the point that there is a need to investigate the factors which influence or not the density and distribution of this fat in the spine, especially at the lumbar level. The purpose was to test the feasibility of a Dixon three-point technique and investigate the vertebral marrow fat distribution.

MATERIAL AND METHODS

A sagittal sequence Iterative Decomposition of Water and Fat with Echo Asymmetry and Least-squares Estimation (IDEAL) IQ was performed on the lumbar spine of 46 subjects who were not suffering from any bone disease (21 women and 25 men, aged 18-77 years). Medulla adiposity was determined directly from the measurement of the fat fraction in each vertebral body (T12 to S1) obtained on the fat cartography automatically generated by the IDEAL sequence.

RESULTS

Average vertebral fat fraction was 36.48% (SD 12.82), with a tendency to increase with age and to higher values among men. We observed a craniocaudal gradient of the fat fraction (β = 1.37; p < 0,001; SD 0.11) increasing with age in the lumbar spine from T12 to L5. Through multivariate analysis, this gradient was adjusted for sex, weight and height of the subjects.

CONCLUSION

This feasibility study shows the existence of a physiological craniocaudal gradient of vertebral medullar adiposity from T12 to L5. This gradient increases with age but it is independent of sex or BMI. The IDEAL sequence allows quick and reproducible measurement of the spine vertebral medullar adiposity.

Assessment of 4D MR Angiography at 3T Compared with DSA for the Follow-up of Embolized Brain Dural Arteriovenous Fistula: A Dual-Center Study

BACKGROUND AND PURPOSE

4D contrast-enhanced MRA in the follow-up of treated dural arteriovenous fistulas has rarely been evaluated. Our aim was to evaluate its diagnostic performance at 3T in the follow-up of embolized dural arteriovenous fistulas using DSA as the standard of reference.

MATERIALS AND METHODS

Patients treated for dural arteriovenous fistulas in 2 centers between 2008 and 2019 were included if they met the following criteria: 1) dural arteriovenous fistula embolization, and 2) follow-up imaging with <6 months between DSA and 4D contrast-enhanced MRA. Two readers reviewed the 4D contrast-enhanced MRA images, first independently, then in consensus to detect any residual/recurrent dural arteriovenous fistula and to grade cases according to the Cognard classification system. Interobserver and intermodality agreement for the detection of a residual dural arteriovenous fistula and stratification of bleeding risk (0-I-IIa; IIb-IIa+b-III-IV-V) was calculated using κ coefficients.

RESULTS

A total of 51 pairs of examinations for 44 patients (median age, 65 years; range, 25-81 years) were analyzed. Interobserver agreement for the detection and stratification of bleeding risk was, respectively, κ = 0.8 (95% CI, 0.6-1) and κ = 0.8 (95% CI, 0.5-1). After consensus review, the sensitivity and specificity of 4D contrast-enhanced MRA for the detection of residual/recurrent dural arteriovenous fistula was 63.6% (95% CI, 40.7%-82.8%) and 96.6% (95% CI, 82.2%-99.9%), respectively. The positive and negative predictive values of 4D contrast-enhanced MRA were 93.3% (95% CI, 68.1%-99.8%) and 77.8% (95% CI, 60.8%-89.9%). Intermodality agreement for the detection and stratification of bleeding risk was good, with κ = 0.60 (95% CI, 0.3-0.8).

CONCLUSIONS

4D contrast-enhanced MRA at 3T is of interest in the follow-up of treated dural arteriovenous fistulas but lacks the sensitivity to replace arteriography.

Surgical site infection following surgery for spinal deformity: About 102 patients

INTRODUCTION

Complex spinal surgery is known to be at risk of complications. Surgical site infection is a serious complication in spine surgery and its frequency is significantly increased in adult spinal deformity correction. The aim of this study is to identify patients' characteristics and risk factors of surgical site infection (SSI) following an osteotomy.

METHODS

This is a single-center retrospective study of patients who underwent an osteotomy between January 2015 and December 2017. Surgical site infection diagnosis was based upon patient's clinical evidence of infection, biologic parameters, microbiological criteria and/or image findings.

RESULTS

In total, 102 patients were eligible and 70 were women (68.6%). Mean age was 65 years old (27-83 years) and mean body mass index (BMI) was 26.14kg.m^-2 (18.4-44.1). Eleven patients were in the SSI group and 91 in the No-SSI group. The mean Schwab grade was 1.5 (1-4) in the SSI group vs. 1.4 (1-5) in the No-SSI group (P=0.435). The mean operative time was on 201.9 minutes (67-377). Mean length of stay was 20.6 days (10-73) in the SSI group vs. 15 days (5-44) in the No-SSI group (P=0.041). Favorable outcome was found in 10 patients (90.9%) in the SSI group.

CONCLUSION

Correction surgery for adult spinal deformity with osteotomies carries a high risk of complications specially SSI. Identification of risk factors, prevention and medical management of SSI should be well assessed.

Effect of emergent carotid stenting during endovascular therapy for acute anterior circulation stroke patients with tandem occlusion: A multicenter, randomized, clinical trial (TITAN) protocol

Background and hypothesis

There is no consensus on the optimal endovascular management of the extracranial internal carotid artery steno-occlusive lesion in patients with acute ischemic stroke due to tandem occlusion. We hypothesized that intracranial mechanical thrombectomy plus emergent internal carotid artery stenting (and at least one antiplatelet therapy) is superior to intracranial mechanical thrombectomy alone in patients with acute tandem occlusion.

Study design

TITAN is an investigator-initiated, multicenter, prospective, randomized, open-label, blinded-endpoint (PROBE) study. Eligibility requires a diagnosis of acute ischemic stroke, pre-stroke modified Rankin Scale (mRS)≤2 (no upper age limit), National Institutes of Health Stroke Scale (NIHSS)≥6, Alberta Stroke Program Early Computed Tomography Score (ASPECTS)≥6, and tandem occlusion on the initial catheter angiogram. Tandem occlusion is defined as large vessel occlusion (intracranial internal carotid artery , M1 and/or M2 segment) and extracranial severe internal carotid artery stenosis ≥90% (NASCET) or complete occlusion. Patients are randomized in two balanced parallel groups (1:1) to receive either intracranial mechanical thrombectomy plus internal carotid artery stenting (and at least one antiplatelet therapy) or intracranial mechanical thrombectomy alone within 8 h of stroke onset. Up to 432 patients are randomized after tandem occlusion confirmation on angiogram.

Study outcomes

The primary outcome measure is complete reperfusion rate at the end of endovascular procedure, assessed as a modified Thrombolysis in Cerebral Infarction (mTICI) 3, and ≥4 point decrease in NIHSS at 24 h. Secondary outcomes include infarct growth, recurrent clinical ischemic event in the ipsilateral carotid territory, type and dose of antiplatelet therapy used, mRS at 90 (±15) days and 12 (±1) months. Safety outcomes are procedural complications, stent patency, intracerebral hemorrhage, and death. Economics analysis includes health-related quality of life, and costs utility comparison, especially with the need or not of endarterectomy.

Discussion

TITAN is the first randomized trial directly comparing two types of treatment in patients with acute ischemic stroke due to anterior circulation tandem occlusion, and especially assessing the safety and efficacy of emergent internal carotid artery stenting associated with at least one antiplatelet therapy in the acute phase of stroke reperfusion.

Trial registration

ClinicalTrials.gov NCT03978988

Mechanical Thrombectomy for Acute Ischemic Stroke Amid the COVID-19 Outbreak: Decreased Activity, and Increased Care Delays

BACKGROUND AND PURPOSE

The efficiency of prehospital care chain response and the adequacy of hospital resources are challenged amid the coronavirus disease 2019 (COVID-19) outbreak, with suspected consequences for patients with ischemic stroke eligible for mechanical thrombectomy (MT).

METHODS

We conducted a prospective national-level data collection of patients treated with MT, ranging 45 days across epidemic containment measures instatement, and of patients treated during the same calendar period in 2019. The primary end point was the variation of patients receiving MT during the epidemic period. Secondary end points included care delays between onset, imaging, and groin puncture. To analyze the primary end point, we used a Poisson regression model. We then analyzed the correlation between the number of MTs and the number of COVID-19 cases hospitalizations, using the Pearson correlation coefficient (compared with the null value).

RESULTS

A total of 1513 patients were included at 32 centers, in all French administrative regions. There was a 21% significant decrease (0.79; [95%CI, 0.76-0.82]; P<0.001) in MT case volumes during the epidemic period, and a significant increase in delays between imaging and groin puncture, overall (mean 144.9±SD 86.8 minutes versus 126.2±70.9; P<0.001 in 2019) and in transferred patients (mean 182.6±SD 82.0 minutes versus 153.25±67; P<0.001). After the instatement of strict epidemic mitigation measures, there was a significant negative correlation between the number of hospitalizations for COVID and the number of MT cases (R² -0.51; P=0.04). Patients treated during the COVID outbreak were less likely to receive intravenous thrombolysis and to have unwitnessed strokes (both P<0.05).

CONCLUSIONS

Our study showed a significant decrease in patients treated with MTs during the first stages of the COVID epidemic in France and alarming indicators of lengthened care delays. These findings prompt immediate consideration of local and regional stroke networks preparedness in the varying contexts of COVID-19 pandemic evolution.

Automated contour detection in spine radiographs and computed tomography reconstructions for forensic comparative identification

This study was conducted to test an automated method to identify unknown individuals. It relies on a previous radiographic file and uses an edge-based comparison of lumbar CT/PMCT reconstructions and radiographs. The living group was composed of 15 clinical lumbar spine CT scans and 15 paired radiographs belonging to the same patients. The deceased group consisted of 5 lumbar spine PMCT scans and 5 paired antemortem radiographs of deceased individuals plus the 15 unpaired radiographs belonging to the living. An automated method using image filtering (anisotropic diffusion) and edge detection (Canny filter) provided image contours. Cross comparisons of all the exams in each group were performed using similarity measurements under the affine registration hypothesis. The Dice coefficient and Hausdorff distance values were significantly linked (p < 0.001 and p = 0.001 respectively) to the matched examinations in the living group (p < 0.001; pseudo-R2 = 0.70). 12 of the 15 examinations were correctly paired, 2 were wrongly paired and 3 were not paired when they must have been. In the deceased group, the Hausdorff distance was significantly linked (p = 0.018) to the matched examinations (p < 0.001; pseudo-R2 = 0.62; Dice coefficient p = 0.138). The paired examinations were all correctly found, but one was wrongly paired. The negative predictive value was above 98% for both groups. We highlighted the feasibility of comparative radiological identification using automated edge detection in cross-modality (CT/PMCT scan and radiographs) examinations. This method could be of significant help to a radiologist or coroner in identifying unknown cadavers.

"Adaptative endovascular strategy to the CloT MRI in large intracranial vessel occlusion" (VECTOR): Study protocol of a randomized control trial

A correlation between the susceptibility vessel sign (SVS) and red thrombi has been identified in MRI. We hypothesized that the Embotrap allow better retrieving of SVS+ thrombi. The AdaptatiVe Endovascular strategy to the CloT MRI in large intracranial vessel Occlusion (VECTOR) trial is a multicenter, prospective and randomized study designed to compare a first-line strategy combining Embotrap added to contact aspiration (CA) versus CA alone in patients with SVS+ occlusions.

Volume variation may be a relevant metric in the study of aneurysm pulsatility: a study using ECG-gated 4D-CTA (PULSAN)

​Background and purpose

Intracranial aneurysms are a frequently occurring disease, with an estimated prevalence of 2–5% in the general population. They usually remain silent until rupture occurs, with a mortality rate of 35–50% and a high rate of morbidity, including long-term disability. However, preventative treatments have their own risk of complications and morbi-mortality rates, including stroke and hemorrhage. ECG-gated four-dimensional CT angiography (4D-CTA) allows the acquisition of time-resolved three-dimensional reconstructions. The aim of our study was to evaluate different intracranial aneurysm metrics over the cardiac cycle using ECG-gated 4D-CTA.

​Materials and methods

ECG-gated 4D-CTA datasets were acquired in patients presenting with intracranial aneurysms. Seven aneurysm metrics, including aneurysm height, aneurysm length, ostium width, aspect ratio, ostium area, volume, and volume-to-ostium ratio, were analysed over different cardiac phases. Intra-reader agreement, inter-reader agreement, and inter-cycle agreement were calculated through the intraclass correlation coefficient.

​Results

Twenty-one aneurysms from 11 patients were considered for inclusion. Post-processing failed for three aneurysms, and 18 aneurysms were finally analysed. There was good intra-reader agreement for each metric (ICC >0.9). Agreements among three consecutive cardiac cycles were calculated for six aneurysms and were especially good for the volume metric (ICC >0.9). Volume variation appears to be the most relevant metric and seems especially perceptible for aneurysms larger than 5 mm.

​Conclusions

Quantification of aneurysm volume changes during the cardiac cycle seems quantitatively possible and reproducible, especially for aneurysms larger than 5 mm. Further studies need to be conducted to validate this parameter for intracranial aneurysm assessment.

Periprocedural safety and technical outcomes of the new Silk Vista Baby flow diverter for the treatment of intracranial aneurysms: results from a multicenter experience

PURPOSE

The aim of our study was to assess the technical success and the safety of this new low-profile flow diverter Silk Vista Baby (SVB) by evaluating the intraprocedural and periprocedural complication rate.

MATERIAL/METHODS

Clinical, procedural, and angiographic data were analyzed.

RESULTS

41 consecutive patients (28 women; age average 50.5 years) with 43 aneurysms were treated with SVB. Aneurysm sizes were classified by their maximum diameter, with an average size of 9.5 mm (range 2-30 mm). Thirty-four cases were unruptured. five aneurysms previously ruptured, had recurrence after the initial coiling. There were two ruptured cases. Aneurysms' locations were: M1 segment (five cases), M2 segment (three cases), M3 segment (one case), middle cerebral artery (MCA) bifurcation (six cases), carotid-T (two cases), anterior communicating artery/A1/A2 (11 cases), pericallosal artery (four cases), supraclinoid ICA (two cases), PCom (one case), V4 segment (three cases), PCA (three cases), SCA (one case), and PICA (one case). We had five intraprocedural complications which resolved without clinical consequences and three events postprocedural events. Initial occlusion rates were: eight aneurysms (18.6%) were completely occluded, five aneurysms (11.6%) showed near-complete occlusion, four cases (9.3%) showed incomplete filling, and 26 cases (60.4%) showed persisting filling. The mRS score at discharge from the hospital did not change from the admission mRS score.

CONCLUSION

Our study demonstrated that the use of the new low-profile flow diverter, SVB device, for the treatment of intracranial aneurysms is feasible and technically safe.

Edge detector-based automatic segmentation of the skin layers and application to moisturization in high-resolution 3 Tesla magnetic resonance imaging

INTRODUCTION

Previous studies have demonstrated the feasibility to explore moisturization with quantification imaging based on T2 mapping. The aim of this study was to describe and validate the first robust automated method to segment the first layers of the skin.

MATERIALS AND METHODS

Data were picked from a previous study that included 35 healthy subjects who underwent a 3T MRI (multi spin echo calculation T2-weighted sequence) with a microscopic coil on the left heel before and one hour after moisturization. The automatic algorithm was composed of the T2 map generation, a Canny filter, a selection of boundaries, and a local regression to delimitate stratum corneum, epidermis, and dermis. An automated affine registration was applied between the exams before and after moisturization.

RESULTS

The failure rate of the algorithm was below 5%. Mean computation time was 139.12s. There was a significant and strong correlation between the automatic measurements and the manual ones for the T2 values (ρ: 0.905, P < 0.001) and for the thickness measurements (ρ: 0.8663; P < 0.001). For registration, mean of the Dice index was 0.64 [0.47; 0.80] and of the Hausdorff distance was 0.29 mm 95% CI: [0.28; 0.30].

CONCLUSION

The proposed automatic method to study the first skin layers in 3T MRI using micro-coils was robust and described T2 values and thickness measurements with a strong correlation to manual measurements. The use of an automated affine registration could also permit the generation of a mapping for a visual assessment of moisturization.

Psoas proximal insertion as a simple and reliable landmark for numbering lumbar vertebrae on MRI of the lumbar spine

OBJECTIVE

To evaluate the value of psoas muscle proximal insertion for correct numbering of the lumbar vertebrae in MRI, in particular in case of lumbosacral transitional vertebra (LSTV).

METHODS

Two radiologists assessed 477 MRI scans of the lumbar spine with a sagittal localizer sequence on the whole spine for numbering vertebrae caudally from C2. Proximal insertion of the psoas was determined as the most proximal vertebra with psoas over half of its body on coronal T2 STIR sequence. The last lumbar vertebra was named considering both its number and the presence or absence of LSTV according to Castellvi classification. These same parameters were also assessed on 207 PET-CT scans of another cohort including the whole spine.

RESULTS

Proximal insertion of the psoas was L1 in 94.1% of cases: 98.5% in case of modal anatomy, 81.4% in case of LSTV, and 51.7% in case of missing or supernumerary lumbar vertebra without LSTV. There was no statistically significant difference between MRI and CT data. The inter-reader agreement for determination of psoas proximal insertion was excellent (kappa = 0.96).

CONCLUSION

Proximal insertion of the psoas muscle is a helpful marker for correct numbering of the lumbar vertebrae in MRI and to detect a complete lumbosacral segmentation anomaly.

KEY POINTS

• Proximal insertion of the psoas muscle can be easily identified on a coronal T2 STIR sequence. • Psoas proximal insertion on the spine almost always designates the first lumbar vertebra and is helpful to accurately number all lumbar vertebrae, especially in case of lumbosacral transitional vertebra. • Conversely, when psoas muscle does not insert five lumbar bodies above the apparent lumbosacral joint, the probability of variation in the number of lumbar vertebrae is high.

Post-mortem X-ray computed tomography (PMCT) identification using ante-mortem CT-scan of the sphenoid sinus

PURPOSE

To evaluate forensic identification of individuals through visual comparison of sphenoid sinus anatomical configuration using ante- and post-mortem CT-scans.

METHOD AND MATERIALS

Ante- and post-mortem head CT-scan of 33 individuals were retrospectively collected. Ten head CT-scans were randomly selected from various neurological contexts and added to the ante-mortem group. Ten other head CT-scans were randomly selected from our post-mortem PACS and added to the post-mortem group. These CT-scans were assigned into 2 groups for analysis: an ante-mortem group (33 + 10) and a post-mortem group (33 + 10). For ethics and to avoid identification bias, CT-scans were anonymized - not showing any head structure but only sphenoid sinuses. An anatomical based classification system using the sphenoid sinuses anatomical variations was created according to anatomical and surgical literature. This classification was used by readers to identify in two different steps a maximum of matched and then unmatched scans.

RESULTS

The first reader had a sensitivity of 100% [CI: 89.4%-100%] and a specificity of 100% [CI: 99.8%-100%]. Sensitivity and specificity were respectively 93.9% [CI: 79.8%-99.3%] and 99.9% [CI: 99.6%-100%] for the second reader. Positive and negative predictive values were respectively 100% [CI: 89.4%-100%] and 100% [CI: 99.8%-100%] for the first reader. Positive and negative values were respectively 96.9% [CI: 83.8%-99.9%] and 99.9% [CI: 99.7%-100%] for the second reader. Inter-reader variability was estimated by Cohen's kappa and an excellent agreement was found.

CONCLUSION

We reported an excellent validity and reliability of subjective visual comparison of ante- and post-mortem CT-data using an anatomical based classification of the sphenoid sinus.