Effect of anesthetic strategies on distal stroke thrombectomy in the anterior and posterior cerebral artery

BACKGROUND

Numerous questions regarding procedural details of distal stroke thrombectomy remain unanswered. This study assesses the effect of anesthetic strategies on procedural, clinical and safety outcomes following thrombectomy for distal medium vessel occlusions (DMVOs).

METHODS

Patients with isolated DMVO stroke from the TOPMOST registry were analyzed with regard to anesthetic strategies (ie, conscious sedation (CS), local (LA) or general anesthesia (GA)). Occlusions were in the P2/P3 or A2-A4 segments of the posterior and anterior cerebral arteries (PCA and ACA), respectively. The primary endpoint was the rate of complete reperfusion (modified Thrombolysis in Cerebral Infarction score 3) and the secondary endpoint was the rate of modified Rankin Scale score 0-1. Safety endpoints were the occurrence of symptomatic intracranial hemorrhage and mortality.

RESULTS

Overall, 233 patients were included. The median age was 75 years (range 64-82), 50.6% (n=118) were female, and the baseline National Institutes of Health Stroke Scale score was 8 (IQR 4-12). DMVOs were in the PCA in 59.7% (n=139) and in the ACA in 40.3% (n=94). Thrombectomy was performed under LA±CS (51.1%, n=119) and GA (48.9%, n=114). Complete reperfusion was reached in 73.9% (n=88) and 71.9% (n=82) in the LA±CS and GA groups, respectively (P=0.729). In subgroup analysis, thrombectomy for ACA DMVO favored GA over LA±CS (aOR 3.07, 95% CI 1.24 to 7.57, P=0.015). Rates of secondary and safety outcomes were similar in the LA±CS and GA groups.

CONCLUSION

LA±CS compared with GA resulted in similar reperfusion rates after thrombectomy for DMVO stroke of the ACA and PCA. GA may facilitate achieving complete reperfusion in DMVO stroke of the ACA. Safety and functional long-term outcomes were comparable in both groups.

Multicenter study of the safety and effectiveness of intracranial aneurysm treatment with the p64MW-HPC flow modulation device

BACKGROUND AND PURPOSE

The new p64 flow diverter with hydrophilic polymer coating (HPC) was designed to reduce thrombogenicity. To date, it is unclear how antithrombogenic surface modifications affect neoendothelialization and thrombus formation in patients with unruptured intracranial aneurysms. The purpose of this study was to evaluate the safety and effectiveness of the p64MW-HPC in the treatment of unruptured aneurysms of small to giant size and of both the anterior and posterior circulation.

MATERIALS AND METHODS

Between March 2020 and October 2022 all patients with unruptured intracranial aneurysms treated with the p64MW-HPC were included at five neurovascular centers. Demographic data, aneurysm characteristics, antiplatelet therapy, procedural complications, and clinical and angiographic outcomes were recorded.

RESULTS

A total of 100 patients with 100 unruptured intracranial aneurysms met the inclusion criteria. Eighty-three aneurysms were classified as saccular, 12 aneurysms were fusiform, 4 aneurysms dissecting, and 1 aneurysm was blister-like. Dual antiplatelet therapy with Clopidogrel and Aspirin was given in 68 cases, and with Ticagrelor and Aspirin in 24 cases. Technical issues with deployment were encountered in 14 cases (torsion (n = 3), foreshortening (n = 8), and incomplete opening (n = 3)). Ischemic stroke occurred in a total of seven cases. In one patient a wire perforation and subsequent severe ICH occurred. Complete aneurysm occlusion at angiographic follow-up (mean time = 7 months) was seen in 73% and adequate occlusion in 93%.

CONCLUSION

This study is the largest multicenter study to date documenting the safety and effectiveness of the new antithrombogenic p64MW-HPC in the treatment of unruptured intracranial aneurysms of the anterior and posterior circulation.

Incidence and outcome of perforations during medium vessel occlusion compared with large vessel occlusion thrombectomy

BACKGROUND

Vessel perforation during thrombectomy is a severe complication and is hypothesized to be more frequent during medium vessel occlusion (MeVO) thrombectomy. The aim of this study was to compare the incidence and outcome of patients with perforation during MeVO and large vessel occlusion (LVO) thrombectomy and to report on the procedural steps that led to perforation.

METHODS

In this multicenter retrospective cohort study, data of consecutive patients with vessel perforation during thrombectomy between January 1, 2015 and September 30, 2022 were collected. The primary outcomes were independent functional outcome (ie, modified Rankin Scale 0-2) and all-cause mortality at 90 days. Binomial test, chi-squared test and t-test for unpaired samples were used for statistical analysis.

RESULTS

During 25 769 thrombectomies (5124 MeVO, 20 645 LVO) in 25 stroke centers, perforation occurred in 335 patients (1.3%; mean age 72 years, 62% female). Perforation occurred more often in MeVO thrombectomy (2.4%) than in LVO thrombectomy (1.0%, p<0.001). More MeVO than LVO patients with perforation achieved functional independence at 3 months (25.7% vs 10.9%, p=0.001). All-cause mortality did not differ between groups (overall 51.6%). Navigation beyond the occlusion and retraction of stent retriever/aspiration catheter were the two most common procedural steps that led to perforation.

CONCLUSIONS

In our cohort, perforation was approximately twice as frequent in MeVO than in LVO thrombectomy. Efforts to optimize the procedure may focus on navigation beyond the occlusion site and retraction of stent retriever/aspiration catheter. Further research is necessary in order to identify thrombectomy candidates at high risk of intraprocedural perforation and to provide data on the effectiveness of endovascular countermeasures.

Brainstem atrophy in dementia with Lewy bodies compared with progressive supranuclear palsy and Parkinson's disease on MRI

BACKGROUND

Although Dementia with Lewy bodies (DLB) is the second most common form of dementia in elderly patients, it remains underdiagnosed compared with Alzheimer's (AD) and Parkinson's diseases (PD). This may be explained by overlapping clinical symptoms, e.g. Parkinsonism. While current MRI research focuses primarily on atrophy patterns of the frontal and temporal lobes, we focus on brainstem characteristics of DLB. In particular, we focused on brainstem atrophy patterns distinguishing DLB from Progressive Supranuclear Palsy (PSP) and PD based as the most common differential diagnoses.

METHODS

We identified patients diagnosed with DLB, PD, PSP, and a control group (CTRL) in our psychiatric and neurological archives. All patients with competing diagnoses and without a high-quality T1 MPRAGE 3D dataset were excluded. We assessed atrophy patterns in all patients (1) manually and (2) using FastSurfer's segmentation algorithm in combination with FreeSurfer's brainstem volumetric calculations. We compared classical measurement methods and ratios with automated volumetric approaches.

RESULTS

One hundred two patients were enrolled and evaluated in this study. Patients with DLB (n = 37) showed on average less atrophy of the brainstem than patients with PSP (n = 21), but a significantly more pronounced atrophy than patients with PD (n = 36) and the control group (CTRL, n = 8). The mean measured sagittal diameters of the midbrain were 8.17 ± 1.06 mm (mean ± standard deviation) for PSP, 9.45 ± 0.95 mm for DLB, 10.37 ± 0.99 mm for PD and 10.74 ± 0.70 for CTRL. The mean measured areas of the midbrain were 81 ± 18 mm² for PSP, 105 ± 17 mm² for DLB, 130 ± 26 mm² for PD and 135 ± 23 mm² for CTRL. The mean segmented volumes of the midbrain were 5595 ± 680 mm³ for PSP, 6051 ± 566 mm³ for DLB, 6646 ± 802 mm³ for PD and 6882 ± 844 mm³ for CTRL. The calculated midbrain pons ratios did not show superiority over the absolute measurements of the midbrain for distinguishing PSP from DLB. Because of the relatively uniform atrophy throughout the brainstem, the ratios were not suitable for distinguishing DLB from PD.

CONCLUSIONS

DLB patients exhibit homogenous atrophy of the brainstem and can be distinguished from patients with PSP and PD by both manual measurement methods and automated volume segmentation using absolute values or ratios.

Thrombectomy versus Medical Management for Isolated Anterior Cerebral Artery Stroke: An International Multicenter Registry Study

Background Evidence supporting a potential benefit of thrombectomy for distal medium vessel occlusions (DMVOs) of the anterior cerebral artery (ACA) is, to the knowledge of the authors, unknown. Purpose To compare the clinical and safety outcomes between mechanical thrombectomy (MT) and best medical treatment (BMT) with or without intravenous thrombolysis for primary isolated ACA DMVOs. Materials and Methods Treatment for Primary Medium Vessel Occlusion Stroke, or TOPMOST, is an international, retrospective, multicenter, observational registry of patients treated for DMVO in daily practice. Patients treated with thrombectomy or BMT alone for primary ACA DMVO distal to the A1 segment between January 2013 and October 2021 were analyzed and compared by one-to-one propensity score matching (PSM). Early outcome was measured by the median improvement of National Institutes of Health Stroke Scale (NIHSS) scores at 24 hours. Favorable functional outcome was defined as modified Rankin scale scores of 0-2 at 90 days. Safety was assessed by the occurrence of symptomatic intracerebral hemorrhage and mortality. Results Of 154 patients (median age, 77 years; quartile 1 [Q1] to quartile 3 [Q3], 66-84 years; 80 men; 94 patients with MT; 60 patients with BMT) who met the inclusion criteria, 110 patients (median age, 76 years; Q1-Q3, 67-83 years; 50 men; 55 patients with MT; 55 patients with BMT) were matched. DMVOs were in A2 (82 patients; 53%), A3 (69 patients; 45%), and A3 (three patients; 2%). After PSM, the median 24-hour NIHSS point decrease was -2 (Q1-Q3, -4 to 0) in the thrombectomy and -1 (Q1-Q3, -4 to 1.25) in the BMT cohort (P = .52). Favorable functional outcome (MT vs BMT, 18 of 37 [49%] vs 19 of 39 [49%], respectively; P = .99) and mortality (MT vs BMT, eight of 37 [22%] vs 12 of 39 [31%], respectively; P = .36) were similar in both groups. Symptomatic intracranial hemorrhage occurred in three (2%) of 154 patients. Conclusion Thrombectomy appears to be a safe and technically feasible treatment option for primary isolated anterior cerebral artery occlusions in the A2 and A3 segment with clinical outcomes similar to best medical treatment with and without intravenous thrombolysis. © RSNA, 2023 Supplemental material is available for this article. See also the editorial by Zhu and Wang in this issue.

Prospective CERAD Neuropsychological Assessment in Patients With Multiple System Atrophy

The objective of the study was to characterize the pattern of cognitive dysfunction in patients with multiple system atrophy (MSA) applying a standardized neuropsychological assessment. A total of 20 patients with the diagnosis of probable or possible MSA were enrolled for neuropsychological assessment applying the CERAD plus battery. All patients were tested at baseline and 14/20 patients received additional follow-up assessments (median follow-up of 24 months). Additionally, relationship between cortical thickness values/subcortical gray matter volumes and CERAD subitems was evaluated at baseline in a subgroup of 13/20 patients. Trail Making Test (TMT) was the most sensitive CERAD item at baseline with abnormal performance (z-score < −1.28) in one or both pathological TMT items (TMT-A, TMT-B) in 60% of patients with MSA. Additionally, there was a significant inverse correlation between the volume of the left and the right accumbens area and the TMT A item after adjusting for age (left side: p = 0.0009; right side p = 0.003). Comparing both subtypes, patients with MSA-C had significant lower values in phonemic verbal fluency (p = 0.04) and a trend for lower values in semantic verbal fluency (p = 0.06) compared to MSA-P. Additionally, patients with MSA-C showed significantly worse performance in the TMT-B task (p = 0.04) and a trend for worse performance in the TMT-A task (p = 0.06). Concerning longitudinal follow-up, a significant worsening in the TMT-B (p = 0.03) can be reported in MSA. In conclusion, frontal-executive dysfunction presents the hallmark of cognitive impairment in MSA.

Flow Diversion for ICA Aneurysms with Compressive Neuro-Ophthalmologic Symptoms: Predictors of Morbidity, Mortality, and Incomplete Aneurysm Occlusion

BACKGROUND AND PURPOSE

Flow diversion is an effective treatment for aneurysms of the ICA with compression-related neuro-ophthalmologic symptoms, especially when treatment is initiated early after symptom onset and aneurysm occlusion is complete. However, non-negligible complication rates have been reported. Our aim was to identify risk factors for morbidity/mortality and incomplete aneurysm occlusion.

MATERIALS AND METHODS

We performed a secondary analysis of a previous publication, which included all patients treated with flow diversion for an unruptured aneurysm of the ICA with compression-related symptoms.

RESULTS

Fifty-four patients with 54 aneurysms (48 women, 88.9%; mean age, 59.2 [SD, 15.9] years; range, 21-86 years) treated with flow diversion were included. We observed morbidity and mortality rates of 7.4% and 3.7%. Increasing age (OR per decade, 3.2; 95% CI, 1.23-8.49; P = .02) and dual-antiplatelet therapy with ticagrelor (OR, 13.9; 95% CI, 1.16-165.97; P = .04) were significantly associated with morbidity/mortality. After a median follow-up of 13.3 [SD, 10.5] months, the rates of complete aneurysm occlusion, neck remnant, and aneurysm remnant were 74%, 14%, and 12%. Incomplete occlusion at follow-up was less frequently observed in aneurysms treated with additional coil embolization (OR, 0.1; 95% CI, 0.01-0.86; P = .04).

CONCLUSIONS

Although a promising treatment for compressive ICA aneurysms, flow diversion carries a relevant risk for complications and incomplete aneurysm occlusion. Our results may help identify patients in which flow diversion may not be the ideal treatment method. Additional coil embolization increased the likelihood of complete aneurysm occlusion at follow-up.

Aspiration Versus Stent Retriever Thrombectomy for Distal, Medium Vessel Occlusion Stroke in the Posterior Circulation: A Subanalysis of the TOPMOST Study

BACKGROUND

The optimal endovascular strategy for reperfusing distal medium-vessel occlusions (DMVO) remains unknown. This study evaluates angiographic and clinical outcomes of thrombectomy strategies in DMVO stroke of the posterior circulation.

METHODS

TOPMOST (Treatment for Primary Medium Vessel Occlusion Stroke) is an international, retrospective, multicenter, observational registry of patients treated for DMVO between January 2014 and June 2020. This study analyzed endovascularly treated isolated primary DMVO of the posterior cerebral artery in the P2 and P3 segment. Technical feasibility was evaluated with the first-pass effect defined as a modified Thrombolysis in Cerebral Infarction Scale score of 3. Rates of early neurological improvement and functional modified Rankin Scale scores at 90 days were compared. Safety was assessed by the occurrence of symptomatic intracranial hemorrhage and intervention-related serious adverse events.

RESULTS

A total of 141 patients met the inclusion criteria and were treated endovascularly for primary isolated DMVO in the P2 (84.4%, 119) or P3 segment (15.6%, 22) of the posterior cerebral artery. The median age was 75 (IQR, 62-81), and 45.4% (64) were female. The initial reperfusion strategy was aspiration only in 29% (41) and stent retriever in 71% (100), both achieving similar first-pass effect rates of 53.7% (22) and 44% (44; P=0.297), respectively. There were no significant differences in early neurological improvement (aspiration: 64.7% versus stent retriever: 52.2%; P=0.933) and modified Rankin Scale rates (modified Rankin Scale score 0-1, aspiration: 60.5% versus stent retriever 68.6%; P=0.4). In multivariable logistic regression analysis, the time from groin puncture to recanalization was associated with the first-pass effect (adjusted odds ratio, 0.97 [95% CI, 0.95-0.99]; P<0.001) that in turn was associated with early neurological improvement (aOR, 3.27 [95% CI, 1.16-9.21]; P<0.025). Symptomatic intracranial hemorrhage occurred in 2.8% (4) of all cases.

CONCLUSIONS

Both first-pass aspiration and stent retriever thrombectomy for primary isolated posterior circulation DMVO seem to be safe and technically feasible leading to similar favorable rates of angiographic and clinical outcome.

Flow diversion for internal carotid artery aneurysms with compressive neuro-ophthalmologic symptoms: clinical and anatomical results in an international multicenter study

BACKGROUND

Scientific data on the safety and efficacy of flow diverter stents (FDS) for the treatment of unruptured internal carotid artery (ICA) aneurysms with compressive neuro-ophthalmological symptoms are scarce. We studied this subject in a retrospective international multicenter series, pooling data of 9 tertiary care neurointerventional departments.

OBJECTIVE

To investigate, in a retrospective, multicentric cohort of patients presenting with visual or oculomotor symptoms attributed to a compressive carotid artery in an unruptured intracranial aneurysm, the safety and efficacy profiles of FDS, by analyzing neuro-opthalmologic symptom evolution following FDS placement, complications, and aneurysm obliteration rates.

METHODS

All patients treated since 2015 with a FDS for an unruptured aneurysm of the ICA with signs of compressive cranial nerve symptoms (CN II, III, IV, VI) were included.

RESULTS

We treated 55 patients with 55 aneurysms; 21 (38.2%) patients had oculomotor and 15 (27.3%) visual symptoms only; 19 (34.5%) presented with a combination of both. Treatment-related morbidity/mortality occurred in 7.2% and 3.6%, respectively. At last imaging follow-up (13.1±10.5 months) rates of complete aneurysm occlusion, neck remnant, and aneurysm remnant were 72%, 14%, and 14%, respectively. At last clinical follow-up after 13±10.5 months, 19/51 (37.3%) patients had recovered completely and 18/51 (35.3%) had recovered at least partially from their neuro-ophthalmological symptoms. In multivariable models, a longer delay between symptom onset and treatment was associated with higher odds for incomplete recovery and lower odds for any improvement (aOR 1.03 (95% CI 1.01 to 1.07), p=0.047 and 0.04 (0-0.81), p=0.020). Incomplete recovery was independently associated with older age and fusiform aneurysms.

CONCLUSION

FDS are effective to treat patients with compressive aneurysms of the ICA causing neuro-ophthalmological symptoms, especially when treatment is initiated early after symptom onset, and aneurysm occlusion is adequate. However, serious complications are not rare.

Thrombectomy for secondary distal, medium vessel occlusions of the posterior circulation: seeking complete reperfusion

BACKGROUND

Whether to approach distal occlusions endovascularly or not in medium-sized vessels secondary to proximal large vessel occlusion stroke remains unanswered.

OBJECTIVE

To investigates the technical feasibility and safety of thrombectomy for secondary posterior circulation distal, medium vessel occlusions (DMVO).

METHODS

TOPMOST (Treatment fOr Primary Medium vessel Occlusion STroke) is an international, retrospective, multicenter, observational registry of patients treated for distal cerebral artery occlusions. This study subanalysis endovascularly treated occlusions of the posterior cerebral artery in the P2 and P3 segment secondary preprocedural or periprocedural thrombus migration between January 2014 and June 2020. Technical feasibility was evaluated with the modified Thrombolysis in Cerebral Infarction (mTICI) scale. Procedural safety was assessed by the occurrence of symptomatic intracranial hemorrhage (sICH) and intervention-related serious adverse events.

RESULTS

Among 71 patients with secondary posterior circulation DMVO who met the inclusion criteria, occlusions were present in 80.3% (57/71) located in the P2 segment and in 19.7% (14/71) in the P3 segment. Periprocedural migration occurred in 54.9% (39/71) and preprocedural migration in 45.1% (32/71) of cases. The first reperfusion attempt led in 38% (27/71) of all cases to mTICI 3. On multivariable logistic regression analysis, increased numbers of reperfusion attempts (adjusted odds ratio (aOR)=0.39, 95% CI 0.29 to 0.88, p=0.009) and preprocedural migration (aOR=4.70, 95% CI,1.35 to 16.35, p=0.015) were significantly associated with mTICI 3. sICH occurred in 2.8% (2/71).

CONCLUSION

Thrombectomy for secondary posterior circulation DMVO seems to be safe and technically feasible. Even though thrombi that have migrated preprocedurally may be easier to retract, successful reperfusion can be achieved in the majority of patients with secondary DMVO of the P2 and P3 segment.

Inhouse Bridging Thrombolysis Is Associated With Improved Functional Outcome in Patients With Large Vessel Occlusion Stroke: Findings From the German Stroke Registry

Background: Endovascular treatment (EVT) for large vessel occlusion stroke (LVOS) is highly effective. To date, it remains controversial if intravenous thrombolysis (IVT) prior to EVT is superior compared with EVT alone. The aim of our study was to specifically address the question, whether bridging IVT directly prior to EVT has additional positive effects on reperfusion times, successful reperfusion, and functional outcomes compared with EVT alone.

Methods: Patients with LVOS in the anterior circulation eligible for EVT with and without prior IVT and direct admission to endovascular centers (mothership) were included in this multicentric, retrospective study. Patient data was derived from the German Stroke Registry (an open, multicenter, and prospective observational study). Outcome parameters included groin-to-reperfusion time, successful reperfusion [defined as a Thrombolysis in Cerebral Infarction (TICI) scale 2b-3], change in National Institute of Health Stroke Scale (NIHSS), modified Rankin Scale (mRS), and mortality at 90 days.

Results: Of the 881 included mothership patients with anterior circulation LVOS, 486 (55.2%) received bridging therapy with i.v.-rtPA prior to EVT, and 395 (44.8%) received EVT alone. Adjusted, multivariate linear mixed effect models revealed no difference in groin-to-reperfusion time between the groups (48 ± 36 vs. 49 ± 34 min; p = 0.299). Rates of successful reperfusion (TICI ≥ 2b) were higher in patients with bridging IVT (fixed effects estimate 0.410, 95% CI, 0.070; 0.750, p = 0.018). There was a trend toward a higher improvement in the NIHSS during hospitalization [ΔNIHSS: bridging-IVT group 8 (IQR, 9.8) vs. 4 (IQR 11) points in the EVT alone group; fixed effects estimate 1.370, 95% CI, −0.490; 3.240, p = 0.149]. mRS at 90 days follow-up was lower in the bridging IVT group [3 (IQR, 4) vs. 4 (IQR, 4); fixed effects estimate −0.350, 95% CI, −0.680; −0.010, p = 0.041]. There was a non-significantly lower 90 day mortality in the bridging IVT group compared with the EVT alone group (22.4% vs. 33.6%; fixed effects estimate 0.980, 95% CI −0.610; 2.580, p = 0.351). Rates of any intracerebral hemorrhage did not differ between both groups (4.1% vs. 3.8%, p = 0.864).

Conclusions: This study provides evidence that bridging IVT might improve rates of successful reperfusion and long-term functional outcome in mothership patients with anterior circulation LVOS eligible for EVT.

Outcomes in young adults with acute ischemic stroke undergoing endovascular thrombectomy: A real-world multicenter experience

Endovascular thrombectomy (EVT) is the standard of care for anterior circulation acute ischemic stroke (AIS) with large vessel occlusion (LVO). Young patients with AIS-LVO have distinctly different underlying stroke mechanisms and etiologies. Much is unknown about the safety and efficacy of EVT in this population of young AIS-LVO patients. All consecutive AIS-LVO patients aged 50 years and below were included in this multicenter cohort study. The primary outcome measured was functional recovery at 90 days, with modified Rankin Scale of 0-2 deemed as good functional outcome. A total of 275 AIS-LVO patients that underwent EVT from 10 tertiary centers in Germany, Sweden, Singapore, and Taiwan were included. Successful reperfusion was achieved in 85.1% (234/275). Good functional outcomes were achieved in 66.0% (182/275). Arterial dissection was the most prevalent stroke etiology (42/195, 21.5%). National Institutes of Health Stroke Scale (NIHSS) score at presentation was inversely related to good functional outcomes (aOR: 0.92, 95% CI: 0.88-0.96 per point increase, p < 0.001). Successful reperfusion (aOR: 3.22, 95% CI: 1.44-7.21, p = 0.005), higher ASPECTS (aOR: 1.21, 95% CI: 1.01-1.44, p = 0.036), and bridging intravenous thrombolysis (aOR: 2.37, 95% CI: 1.29-4.34, p = 0.005) independently predicted good functional outcomes. Successful reperfusion was inversely associated with in-hospital mortality (aOR: 0.14, 95% CI: 0.03-0.57, p = 0.006). History of hypertension strongly predicted in-hospital mortality (aOR: 4.59, 95% CI: 1.10-19.13, p = 0.036). While differences in functional outcomes exist across varying stroke aetiologies, high rates of successful reperfusion and good outcomes are generally achieved in young AIS-LVO patients undergoing EVT.

Thrombectomy for Primary Distal Posterior Cerebral Artery Occlusion Stroke: The TOPMOST Study

Importance

Clinical evidence of the potential treatment benefit of mechanical thrombectomy for posterior circulation distal, medium vessel occlusion (DMVO) is sparse.

Objective

To investigate the frequency as well as the clinical and safety outcomes of mechanical thrombectomy for isolated posterior circulation DMVO stroke and to compare them with the outcomes of standard medical treatment with or without intravenous thrombolysis (IVT) in daily clinical practice.

Design, Setting, and Participants

This multicenter case-control study analyzed patients who were treated for primary distal occlusion of the posterior cerebral artery (PCA) of the P2 or P3 segment. These patients received mechanical thrombectomy or standard medical treatment (with or without IVT) at 1 of 23 comprehensive stroke centers in Europe, the United States, and Asia between January 1, 2010, and June 30, 2020. All patients who met the inclusion criteria were matched using 1:1 propensity score matching.

Interventions

Mechanical thrombectomy or standard medical treatment with or without IVT.

Main Outcomes and Measures

Clinical end point was the improvement of National Institutes of Health Stroke Scale (NIHSS) scores at discharge from baseline. Safety end point was the occurrence of symptomatic intracranial hemorrhage and hemorrhagic complications were classified based on the Second European-Australasian Acute Stroke Study (ECASSII). Functional outcome was evaluated with the modified Rankin Scale (mRS) score at 90-day follow-up.

Results

Of 243 patients from all participating centers who met the inclusion criteria, 184 patients were matched. Among these patients, the median (interquartile range [IQR]) age was 74 (62-81) years and 95 (51.6%) were female individuals. Posterior circulation DMVOs were located in the P2 segment of the PCA in 149 patients (81.0%) and in the P3 segment in 35 patients (19.0%). At discharge, the mean NIHSS score decrease was -2.4 points (95% CI, -3.2 to -1.6) in the standard medical treatment cohort and -3.9 points (95% CI, -5.4 to -2.5) in the mechanical thrombectomy cohort, with a mean difference of -1.5 points (95% CI, 3.2 to -0.8; P = .06). Significant treatment effects of mechanical thrombectomy were observed in the subgroup of patients who had higher NIHSS scores on admission of 10 points or higher (mean difference, -5.6; 95% CI, -10.9 to -0.2; P = .04) and in the subgroup of patients without IVT (mean difference, -3.0; 95% CI, -5.0 to -0.9; P = .005). Symptomatic intracranial hemorrhage occurred in 4 of 92 patients (4.3%) in each treatment cohort.

Conclusions and Relevance

This study suggested that, although rarely performed at comprehensive stroke centers, mechanical thrombectomy for posterior circulation DMVO is a safe, and technically feasible treatment option for occlusions of the P2 or P3 segment of the PCA compared with standard medical treatment with or without IVT.

Abstract P493: Outcomes in Young Adults With Acute Ischemic Stroke Undergoing Endovascular Thrombectomy: A Multi-Centre Experience

Introduction: Endovascular thrombectomy(EVT) is considered standard of care for anterior circulation acute ischemic stroke(AIS) with large vessel occlusion(LVO). Young AIS-LVO patients have distinctly different underlying stroke mechanisms and etiologies.

Methods: In this multicenter cohort study conducted from August 2014 to January 2020, we investigated the safety and effectiveness of EVT in young AIS-LVO patients aged≤50 years and evaluated associations between demographics, stroke etiology, neuroimaging factors and clinical outcomes, including functional outcomes, in-hospital mortality and symptomatic intracranial haemorrhage(sICH) in univariable and multivariable regression models.

Results: 275 AIS-LVO patients from 10 tertiary centers in Germany, Sweden, Singapore and Taiwan were included. The more common TOAST subtypes included cardioembolism (82/275, 29.8%) and stroke of undetermined etiology (85/275, 30.9%). Arterial dissection was the most prevalent stroke etiology (42/195, 21.5%) and had the highest rate of good functional outcomes (29/42, 69.0%). Successful reperfusion was achieved in 85.1% (234/275). Excellent and good functional outcomes were achieved in 48.0% (132/275) and 66.0% (182/275) respectively. sICH occurred in 6.5% (18/275). National Institute of Health Stroke Scale (NIHSS) at presentation was inversely related with good functional outcomes (aOR0.92, 95% CI 0.88- 0.96 per point increase, p<0.001). Successful reperfusion (aOR3.22, 95% CI 1.44-7.21, p=0.005), higher ASPECTS (aOR1.21, 95% CI 1.01-1.44, p=0.036) and bridging intravenous thrombolysis (aOR2.37, 95% CI 1.29-4.34, p=0.005) independently predicted good functional outcomes. Higher initial NIHSS (aOR1.08, 95% 1.02-1.14, p=0.007) and lower ASPECTS (aOR0.73, 95% 0.58-0.93, p=0.012) were associated with sICH. Successful reperfusion was inversely associated with in-hospital mortality (aOR0.14, 95% CI 0.03-0.57, p=0.006). Hypertension strongly predicted in-hospital mortality (aOR4.59, 95% CI 1.10-19.13, p=0.036).

Conclusion: While differences in functional outcomes exist across varying stroke aetiologies, high rates of successful reperfusion and good outcomes are generally achieved in young AIS-LVO patients undergoing EVT.

Use of antibiotics and the prevalence of antibiotic-associated diarrhoea in patients with spinal cord injuries: an international, multi-centre study

BACKGROUND

Little is known about the use of antibiotics and the extent of antibiotic-associated diarrhoea (AAD) in patients with spinal cord injuries (SCIs).

AIMS

To record the use of antibiotics, establish the prevalence of AAD and Clostridium difficile infection (CDI), and assess if there was any seasonal variation in antibiotic use and incidence of AAD in patients with SCIs.

METHODS

A retrospective study was conducted in six European SCI centres between October 2014 and June 2015. AAD was defined as two or more watery stools (Bristol Stool Scale type 5, 6 or 7) over 24 h.

FINDINGS

In total, 1267 adults (median age 54 years, 30.7% female) with SCIs (52.7% tetraplegia, 59% complete SCI) were included in this study. Among the 215 (17%) patients on antibiotics, the top three indications for antibiotics were urinary tract infections (UTIs), infected pressure ulcers and other skin infections. Thirty-two of these 215 (14.9%) patients developed AAD and two patients out of the total study population (2/1267; 0.16%) developed CDI. AAD was more common in summer than in spring, autumn or winter (30.3% vs 3.8%, 7.4% and 16.9%, respectively; P<0.01). AAD was associated with age ≥65 years, tetraplegia, higher body mass index, hypoalbuminaemia, polypharmacy, multiple antibiotic use and high-risk antibiotic use. Summer and winter seasons and male sex were identified as independent predictors for the development of AAD.

CONCLUSION

This survey found that AAD is common in patients with SCIs, and UTI is the most common cause of infection. Summer and winter seasons and male sex are unique predictors for AAD. Both AAD and UTIs are potentially preventable; therefore, further work should focus on preventing the over-use of antibiotics, and developing strategies to improve hospital infection control measures.

Validation of the spinal nutrition screening tool (SNST) in patients with spinal cord injuries (SCI): result from a multicentre study

BACKGROUND/OBJECTIVES

A disease-specific nutrition screening tool (NST): the spinal nutrition screening tool (SNST) has been developed for use in patients with spinal cord injury (SCI) but its reliability and agreement with other published tools requires investigation. The aims of this study were to assess the prevalence of malnutrition risk in SCI patients and to confirm the diagnostic accuracy of the SNST.

SUBJECTS/METHODS

Patients' baseline clinical data, anthropometric measurements and NST scores were assessed. The validity of the SNST was assessed by (i) comparing with a full dietetic assessment (criterion validity); (ii) comparison with a generic NST: malnutrition universal screening tool (MUST) (concurrent validity); and (iii) completion of an additional SNST to assess inter- and intra-rater reliability. Agreement was assessed using Cohen's κ-statistics.

RESULTS

Using the SNST, the prevalence of malnutrition risk ranged from 22 to 64% on admission to four SCI centres. The SNST had substantial agreement with MUST (κ: 0.723, 95% confidence interval (CI): 0.607-0.839) and dietitian assessment (κ: 0.567, 95% CI: 0.434-0.699). The SNST had a moderate to substantial reliability (inter-rater reliability: κ: 0.5, 95% CI: 0.2-0.8; intra-rater reliability: κ: 0.64, 95% CI: 0.486-0.802). When compared with dietetic assessment, the SNST had a numerically lower specificity (76.1% vs 80.4%) and similar agreement to MUST (κ: 0.57 vs 0.58) but SNST showed a numerically higher sensitivity (85.7% vs 80.4%) and a numerically higher negative predictive value (92% vs 89.2%) than MUST.

CONCLUSIONS

This study shows that malnutrition is common in SCI patients. The SNST is an acceptable (valid and reliable) NST and may be a useful alternative to MUST in identifying SCI patients at risk of malnutrition.

A low-dose radioisotope procedure for assessment of subcutaneous drug delivery systems used for slow intrathecal infusion of antispasmodic agents

STUDY DESIGN

Retrospective single centre study.

OBJECTIVES

To evaluate a low-dose radioisotope imaging procedure for assessment of implanted intrathecal drug delivery and to compare the radiation dose and diagnostic value of these studies with other reported studies using higher administered radiation dose.

SETTING

National Spinal Injuries Centre, Stoke Mandeville Hospital, UK.

METHOD

A total of 11 spinally injured patients with subcutaneous drug delivery systems and uncontrolled spasm were investigated for catheter failure using a low-dose radioisotope procedure with an administered dose of radioactivity of 40 MBq Technetium-99m.

RESULTS

Loss of catheter patency was demonstrated in six patients, enabling identification of the site of blockage. Catheter patency and subsequent perfusion of CSF (ie normal result) was demonstrated in five patients. Radiation effective dose was estimated at 1.3 mSv per patient study, with a low associated risk of deleterious effect of one in 13,000.

CONCLUSION

Radioisotope investigation using a reduced administered dose of 40 MBq Technetium-99m DTPA, formulated according to a strict radiopharmaceutical protocol, provides a safe test for assessment of intrathecal drug delivery systems.

Towards improved clinical and physiological assessments of recovery in spinal cord injury: a clinical initiative

Clinical practice and scientific research may soon lead to treatments designed to repair spinal cord injury. Repair is likely to be partial in the first trials, extending only one or two segments below the original injury. Furthermore, treatments that are becoming available are likely to be applied to the thoracic spinal cord to minimise loss of function resulting from damage to surviving connections. These provisos have prompted research into the improvement of clinical and physiological tests designed (1) to determine the level and density of a spinal cord injury, (2) to provide reliable monitoring of recovery over one or two spinal cord segments, and (3) to provide indices of function provided by thoracic spinal root innervation, presently largely ignored in assessment of spinal cord injury. This article reviews progress of the Clinical Initiative, sponsored by the International Spinal Research Trust, to advance the clinical and physiological tests of sensory, motor and autonomic function needed to achieve these aims.

The inter rater reliability of the original and of the modified Ashworth scale for the assessment of spasticity in patients with spinal cord injury

Thirty patients with spinal cord injury (SCI) were randomly selected to participate in this study which evaluated the inter rater reliability of the original and of the modified Ashworth scale for the assessment of spasticity in the lower limbs. A doctor and a physiotherapist rated the muscle tone of hip adductors, hip extensors, hip flexors and ankle plantarflexors according to the original and to the modified Ashworth scale. The results were analyzed using a Cohen's Kappa statistical test and showed varying levels of reliability for different muscle groups and limbs. Kappa values ranged between 0.21 and 0.61 (mean 0.37). The original scale was slightly more reliable than was the modified scale. However, this difference was not significant (P > 0.05), and was not consistent between the two limbs and between different muscle groups. It was concluded that the Ashworth scale is of limited use in the assessment of spasticity in the lower limb of patients with SCI. Further work is required to establish a standardised speed of muscle stretching during the test, or to find more appropriate grades and descriptions of spasticity for this patient group. The effects of training of the raters in the use of the scales also warrants further investigation.

Intrathecal baclofen--a multicentre clinical comparison of the Medtronics Programmable, Cordis Secor and Constant Infusion Infusaid drug delivery systems

A retrospective review was carried out of 34 consecutive traumatic spinal cord damaged patients who have had the Medtronics Programmable, Cordis Secor or Constant Infusion Infusaid intrathecal baclofen drug delivery systems inserted between July 1987 and 1992. The results indicate that whilst this treatment has many benefits there is a significant risk of complications, some potentially fatal. It should only be provided by a skilled and experienced team. The Medtronics Programmable pump is an excellent pump. It is of particular benefit where the therapeutic window is small or fine-tuning required. The Constant Infusion Infusaid is adequate if less precise control and continuous infusion is sufficient. It is of particular benefit in financially disadvantaged countries. The Cordis Secor device is helpful when unpredictable intermittent relief of spasticity is required but is otherwise limited by its complication rate.

A comparison of the chest radiograph and computerised tomography in assessing lung changes in acute spinal injuries--an assessment of their prevalence and the accuracy of the chest X-ray compared with CT in their assessment

Lung function in patients following an acute spinal injury is frequently much more compromised than may be expected from the level of injury and the chest radiograph appearance. Experimental evidence in anaesthetised patients and subsequently our own experience with patients with acute spinal injuries suggested that in paralysed patients lung changes were frequent and that in many spinal patients large pleural effusions and lung consolidation could be present without the usual associated chest radiograph changes being recognised. This study was performed to assess the prevalence of chest pathology and the sensitivity of the chest radiograph in portraying it. Sixty patients (50 males, 10 females, 31 cervical, 29 thoracic or thoracolumbar; 15 incomplete, 45 complete; ages 17-66, mode 22 years) with spinal injuries from a variety of causes were assessed with a supine chest radiograph and three computerised tomography axial cuts at standardised locations through the thorax. The chest radiograph agreed with the computerised tomography in only 12 patients (six normal, six abnormal). The chest radiograph suggested that there were 19 normals but computerised tomography only showed 12. In a total of 35 patients, the chest radiograph significantly underestimated the degree of change and in 13 the chest radiograph suggested greater pathology than was shown on computerised tomography. Thirteen of the 20 patients with cervical lesions but no chest trauma had lung changes.(ABSTRACT TRUNCATED AT 250 WORDS)

Psychological and emotional effects of the use of oral baclofen: a preliminary study

Spasticity is a common problem following spinal cord injury. The drug of choice to control spasms is baclofen. There would appear to be no reported studies which have evaluated the psychological and emotional effect of this drug. This preliminary study investigated a number of such effects, including depression, anxiety and general mood state. First, we examined 10 subjects before and during the administration of baclofen. They were then compared to a control group of 12 subjects. A second cohort of 12 subjects taking baclofen were compared to a control group of nine subjects at a specific time after injury. Results indicated that whilst some significant differences were found, suggesting an increase in fatigue with use of baclofen, no major adverse psychological effects were noted. The implications of these results were discussed and suggestions for further research were highlighted.

Ultrasound in the early diagnosis of heterotopic ossification in patients with spinal injuries

Heterotopic ossification (HO) is a potentially disabling complication of spinal injuries and other chronic disorders. It is of unknown aetiology and currently there is no easy or convenient diagnostic method that will allow very early confirmation of the inflammatory changes that precede osteoid and, later, true bone formation. Clinical experience, however, indicates that early treatment with radiotherapy, antiinflammatory agents or diphosphonates is needed to control the progression. This study was undertaken to assess the role of ultrasound (US) in the very early diagnosis of HO in patients with spinal injuries. US was found to be very sensitive in detecting focal soft tissue abnormalities around joints and in the muscles of these patients. If combined with a Doppler study to exclude deep venous thrombosis (DVT), and infection or tumour could be excluded clinically, US was extremely accurate in predicting the presence or absence of early HO changes within hours of the clinical manifestation. In 2 patients it successfully predicted HO in the opposite leg before clinical signs were evident. This study also provided supportive evidence of the theory of microtrauma in the aetiology of HO. As ultrasound is portable, safe, cheap, reproducible and accurate, it is the method of choice in the early diagnosis of HO. It allows early treatment to prevent the formation of osteoid and subsequent bone formation.

Complications of intrathecal baclofen delivery

The medical records of 46 consecutive patients who have had intrathecal Baclofen drug delivery systems implanted in the National Spinal Injuries Centre, the Paddocks Hospital Spinal Unit, Princes Risborough, Lodge Moor Hospital Spinal Unit, Sheffield, the Northern Regional Spinal Injuries Unit, Hexham and The Radcliffe Infirmary, Oxford, were reviewed. Patients were contacted to describe their views on the treatment. The complications of the treatment are described. Some, such as overdose and meningitis are particularly hazardous. Others, in particular pump tubing revisions, are more of an inconvenience and time consuming for the patient and physician. If the serious risks of this valuable treatment are to be minimized and the therapy applied most effectively than a well co-ordinated team is essential, involving in particular the physician responsible for the initial assessment and follow-up of the patient and an experienced surgeon. It is recommended that only a small number of centres in the UK undertake these implants.

Intrathecal baclofen for long-term treatment of spasticity: a multi-centre study

Twenty eight patients with severe, intractable spasticity have been treated by chronic intrathecal administration of baclofen. An implantable programmable drug-administration-device (DAD) was used with a permanent intrathecal catheter. Infusion of 50 to 800 micrograms/day of baclofen completely abolished spasticity. Follow-up was up to two years. Therapeutic effect was documented by clinical assessment of tone, spasms and reflexes and by electrophysiological recordings of mono- and polysynaptic reflex activity. Complications and untoward side-effects of the procedure were few. This procedure is recommended for spasticity of spinal origin refractory to physiotherapy and oral medication. It is a preferable alternative to ablative surgical intervention.