Comparison of Measurement Techniques and Response Criteria for MR Imaging Follow-up in Adult Primary Central Nervous System Lymphoma.

BACKGROUND AND PURPOSE: Current guidelines proposed for the measurement of primary central nervous system lymphoma in 2005 have indicated that unidimensional and bidimensional measurements may be used, using the same threshold for response categorization, because no clinical study has evaluated the agreement among the measurement techniques. Hence, our study assessed the agreement among different measurements. MATERIALS AND METHODS: In this retrospective study, primary central nervous system lymphoma lesions were measured with different techniques (longest 1D, axial 1D, 2D, 3D, and the Response Evaluation Criteria in Solid Tumor) on consecutive MR images. Intra- and interobserver correlations were calculated with intraclass correlation coefficients. Correlations between raw measurements and variations in size compared with baseline were evaluated with the Spearman rank correlation, and agreement among response categories was evaluated. RESULTS: A total of 304 examinations obtained in 40 patients was assessed. The intraobserver intraclass correlation coefficient for 3D, 2D, and longest 1D were ≥0.993. The interobserver intraclass correlation coefficient was ≥0.967. The correlations in raw measurements and size variation in comparison with 3D were respectively; 0.99 and 0.98 for 2D; 0.94 and 0.92 for longest 1D; 0.94 and 0.83 for axial 1D; and 0.90 and 0.79 for Response Evaluation Criteria in Solid Tumor. With 20%-30% and 25%-50% thresholds for unidimensional techniques, response categorizations were 95% and 95% for 2D, 92.5% and 90% for the longest 1D, 87.5% and 82.5% for axial 1D, and 90% and 85% for the Response Evaluation Criteria in Solid Tumor. CONCLUSIONS: Both longest 1D and 2D demonstrated excellent correlations with 3D measurements. The longest 1D could be used for the follow-up of primary central nervous system lymphoma. If unidimensional measurements were used, 20% and 30% cutoffs should be used for defining response categorization instead of the current guidelines.

Patient selection for stroke endovascular therapy--DWI-ASPECTS thresholds should vary among age groups: insights from the RECOST study.

BACKGROUND AND PURPOSE: The purpose of this study was to evaluate the benefits of endovascular intervention in large-vessel occlusion strokes, depending on age class. MATERIALS AND METHODS: A clinical management protocol including intravenous treatment and mechanical thrombectomy was instigated in our center in 2009 (Prognostic Factors Related to Clinical Outcome Following Thrombectomy in Ischemic Stroke [RECOST] study). All patients with acute ischemic stroke with an anterior circulation major-vessel occlusion who presented within 6 hours were evaluated with an initial MR imaging examination and were analyzed according to age subgroups (younger than 50 years, 50-59 years, 60-69 years, 70-79 years; 80 years or older). The mRS score at 3 months was the study end point. RESULTS: One hundred sixty-five patients were included in the analysis. The mean age was 67.4 years (range, 29-90 years). The mean baseline NIHSS score was 17.24 (range, 3-27). The mean DWI-derived ASPECTS was 6.4. Recanalization of TICI 2b/3 was achieved in 80%. At 3 months, 41.72% of patients had a good outcome, with a gradation of prognosis depending on the age subgroup and a clear cutoff at 70 years. Only 19% of patients older than 80 years had a good outcome at 3 months (mean ASPECTS = 7.4) with 28% for 70-79 years (mean ASPECTS = 6.8), but 58% for 60-69 years (mean ASPECTS = 6), 52% for 50-59 years (mean ASPECTS = 5.91), and 72% for younger than 50 years (mean ASPECTS = 6.31). In contrast, the mortality rate was 35% for 80 years and older, and 26% for 70-79 versus 5%-9% for younger than 70 years. CONCLUSIONS: The elderly may benefit from thrombectomy when their ischemic core volume is low in comparison with younger patients who still benefit from acute recanalization despite larger infarcts. Stroke volume thresholds should, therefore, be related and adjusted to the patient's age group.

Stent retrievers in acute ischemic stroke: complications and failures during the perioperative period.

BACKGROUND AND PURPOSE: Stent retriever-assisted thrombectomy promotes high recanalization rates in acute ischemic stroke. Nevertheless, complications and failures occur in more than 10% of procedures; hence, there is a need for further investigation. MATERIALS AND METHODS: A total of 144 patients with ischemic stroke presenting with large-vessel occlusion were prospectively included. Patients were treated with stent retriever-assisted thrombectomy ± IV fibrinolysis. Baseline clinical and imaging characteristics were incorporated in univariate and multivariate analyses. Predictors of recanalization failure (TICI 0, 1, 2a), and of embolic and hemorrhagic complications were reported. The relationship between complication occurrence and periprocedural mortality rate was studied. RESULTS: Median age was 69.5 years, and median NIHSS score was 18 at presentation. Fifty patients (34.7%) received stand-alone thrombectomy, and 94 (65.3%) received combined therapy. The procedural failure rate was 13.9%. Embolic complications were recorded in 12.5% and symptomatic intracranial hemorrhage in 7.6%. The overall rate of failure, complications, and/or death was 39.6%. The perioperative mortality rate was 18.4% in the overall cohort but was higher in cases of failure (45%; P = .003), embolic complications (38.9%; P = .0176), symptomatic intracranial hemorrhages (45.5%; P = .0236), and intracranial stenosis (50%; P = .0176). Concomitant fibrinolytic therapy did not influence the rate of recanalization or embolic complication, or the intracranial hemorrhage rate. Age was the only significant predictive factor of intracranial hemorrhage (P = .043). CONCLUSIONS: The rate of perioperative mortality was significantly increased in cases of embolic and hemorrhagic complications, as well as in cases of failure and underlying intracranial stenoses. Adjunctive fibrinolytic therapy did not improve the recanalization rate or collateral embolic complication rate. The rate of symptomatic intracranial hemorrhage was not increased in cases of combined treatment.

Evaluation of an intravenous-endovascular strategy in patients with acute proximal middle cerebral artery occlusion.

BACKGROUND AND PURPOSE: IVT administered in acute ischemic stroke provides low recanalization rates in proximal intracranial occlusions, with consequently poor clinical outcome. The safety and efficacy of an IES by using mechanical thrombectomy after IVT failure were assessed in acute MCA occlusions. MATERIALS AND METHODS: Patients presenting with acute MCA occlusion within 4.5 hours with an NIHSS score between 8 and 25 and a DWI ASPECTS of >5 were eligible. From September 2009 to September 2010, mechanical thrombectomy by using the Solitaire FR device was systematically performed if no clinical improvement was observed 1 hour after the initiation of IVT (IES group). Results in terms of clinical outcome were compared with those from an IVT series from January 2007 to August 2009 (IVT group). RESULTS: Alteplase was administered in 123 patients with proximal intracranial occlusion. Fifty-six had a confirmed MCA occlusion: 32 were included in the IVT group; and 24, in the IES group. At 24 hours, the median NIHSS improvement was 8.5 points in the IES group (25%-75% CI, 1.5-13) and 3 points in the IVT group (25%-75% CI, 1-5) (P = .001). At 3 months, 17/22 (77%) patients from the IES group and 15/30 (50%) from the IVT group had an mRS score of ≤2. After adjustment for confounding variables, IES was strongly associated with favorable clinical outcome (77% versus 50%; adjusted odds ratio = 11.9; 95% CI, 1.6-89.1; P < .02). No symptomatic intracranial hemorrhage was observed. CONCLUSIONS: IES by using systematic mechanical thrombectomy after IVT failure safely improves the clinical outcome at 3 months and could represent an interesting alternative in the management of patients with acute MCA occlusion.

Prognostic factors related to clinical outcome following thrombectomy in ischemic stroke (RECOST study). 50 patients prospective study.

BACKGROUND AND AIMS: New thrombectomy devices allow successful and rapid recanalization in acute ischemic stroke. Nevertheless prognostics factors need to be systematically analyzed in the context of these new therapeutic strategies. The aim of this study was to analyze prognostic factors related to clinical outcome following Solitaire FR thrombectomy in ischemic stroke. METHODS: Fifty consecutive ischemic stroke patients with large vessel occlusion were included. Three treatment strategies were applied; rescue therapy, combined therapy, and standalone thrombectomy. DWI ASPECT score<5 was the main exclusion criterion after initial MRI (T2, T2, TOF, FLAIR, DWI). Sexes, age, time to recanalization were prospectively collected. Clinical outcome was assessed post treatment, day one and discharge by means of a NIHSS. Three months mRS evaluation was performed by an independent neurologist. The probability of good outcome at 3 months was assessed by forward stepwise logistic regression using baseline NIHSS score, Glasgow score at entrance, hyperglycemia, dyslipidemia, blood-brain barrier disruption on post-operative CT, embolic and hemorrhagic post procedural complication, ischemic brain lesion extension on 24h imaging, NIHSS at discharge, ASPECT score, and time to recanalization. All variables significantly associated with the outcome in the univariate analysis were entered in the model. The significance of adding or removing a variable from the logistic model was determined by the maximum likelihood ratio test. Odds-ratio (OR) and their 95% confidence intervals were calculated. RESULTS: At 3 months 54% of patients had a mRS 0-2, 70% in MCA, 44% in ICA, and 43% in BA with an overall mortality rate of 12%. Baseline NIHSS score (p=0.001), abnormal Glasgow score at entrance (p=0.053) hyperglycemia (p=0.023), dyslipidemia (p=0.031), blood-brain barrier disruption (p=0.022), embolic and hemorrhagic post procedural complication, ischemic brain lesion extension on 24h imaging (p=0.008), NIHSS at discharge (0.001) were all factors significantly associated with 3 month clinical outcome. ASPECT subgroup (5-7 and 8-10), and time to recanalization were not correlated to 3 months outcome. Baseline NIHSS score (OR, 1.228; 95% CI, 1.075-1.402; p=0.002), hyperglycemia (OR, 10.013; 95% CI, 1.068-93.915; p=0.04), emerged as independent predictors of outcome at 3 months. Overall embolic complication rate was 10%, and symptomatic intracranial hemorrhage was 2%. CONCLUSION: The MCA location was associated with the best clinical outcome. A DWI ASPECT cutoff score of 5 was reliable and safe. No correlation with time to recanalization was observed in this study. NIHSS and hyperglycemia at admission were the two factors independently associated with a bad outcome at 90 days.

Stent-assisted coiling of complex middle cerebral artery aneurysms: initial and midterm results.

BACKGROUND AND PURPOSE: Clinical outcome and initial and midterm angiographic results of EVT of complex MCA aneurysms by using the stent-assisted coiling technique were retrospectively evaluated in our center where EVT of intracranial aneurysms is the first treatment option. MATERIALS AND METHODS: From November 2003 to October 2009, 49 patients (27 men, 22 women; mean age, 52 ± 12 years) harboring 52 complex unruptured MCA aneurysms (11 ruptured previously and coiled but recanalized and 41 unruptured) were treated by EVT by using self-expandable intracranial stents. Procedural complications, clinical outcome, and initial and midterm angiographic results were evaluated. Initial treatment status and aneurysm sac size were tested as potential risk factors for recurrence. RESULTS: After successful stent deployment, coiling was performed in 50 aneurysms (96.2%) in 47 patients; however, 2 failures (3.8%) occurred in 2 patients. Ten intrastent clot formations (20%) observed on final control angiography induced 2 permanent moderate disabilities (GOS score = 2). Mortality and permanent neurologic morbidity were 0% and 4.3%, respectively. At a mean period of 14 ± 9 months, among 48 aneurysms in 45 patients eligible for follow-up, 34 complete (71%) and 14 partial treatments (29%) were observed, 7 recurrences (14.6%) occurred, and 5 patients (10.4%) needed retreatment. No aneurysm bleeding or symptomatic intrastent stenosis was observed. Aneurysm sac size ≥7 mm and incomplete initial treatment were associated with more recurrences without a statistically significant difference. CONCLUSIONS: For complex unruptured MCA aneurysms, EVT by using a self-expandable intracranial stent was feasible, safe, and durable and could be considered as the first-option treatment.