Positive effects of lumbar puncture simulation training for medical students in clinical practice.

BACKGROUND: Lumbar puncture (LP) is an invasive medical procedure that can be done by any doctor. Several simulation-based trainings have been built however the evaluations of the theoretical knowledge and the impact of the simulation-based training have never been performed in real life. The objective was to evaluate the impact of a LP training on the theoretical knowledge improvement and the performance of a LP in clinical practice. METHODS: Before and after medical students' training, theoretical knowledge and confidence level were assessed. Over a 6 months period, the impact of simulation training was evaluated by the success rate of students' first LP carried out in hospitalized patients and compared to the results of a no-training control. RESULTS: Students' theoretical knowledge and confidence level showed significant improvement after simulation training on 115 students (p < 0.0001). The evaluation in real life based on 41 students showed that the success rate of the first LP in patients was higher in the LP simulation group compared to the control group (67% vs 14%, p = 0.0025). The technical assistance was also less frequently needed in the LP simulation group (19% vs 57%, respectively, p = 0.017). The rate of students who participated in this educational study was low. DISCUSSION: Simulation-based teaching was an effective way to improve students' theoretical and practical knowledge. Whether this approach translates to other procedural skills in real clinical settings merits further study. The low participation rate in the study is due to the fact that students are not used to be included in educational studies and to the complexity of evaluation in routine clinical practice.

Increased Multispectral CT Iodine Concentrations in Patients With Transient Neurological Deterioration Following Endovascular Neurointerventional Procedures: an Argument in Favor of the Elusive Contrast-Induced Encephalopathy?

BACKGROUND AND PURPOSE: So-called contrast-induced encephalopathy (CIE) is a rare but worrying condition occurring after cerebral angiography or neuroendovascular interventions using iodine contrast media. This study aimed to compare cerebral iodine concentrations in patients suspected of having CIE after endovascular procedures to those in matched controls. METHODS: This is a retrospective monocentric study of 25 suspected CIE patients in a tertiary care teaching hospital diagnosed from June 2017 to February 2024. Cerebral multispectral computed tomography (CT) iodine mean concentrations were measured and compared with 1:1 matched controls using the CT constructor's workstation in the whole brain and in specific regions of interest (ROIs) corresponding to a vascular territory downstream of the procedure. Concentration values were compared with paired samples t­test. RESULTS: During the study period, 1097 patients underwent aneurysm embolization and 137 arteriovenous malformation (AVM) embolization procedures. So-called CIE was suspected in 25 patients after aneurysm or AVM embolization (2%). Mean iodine concentrations in the procedure vascular territory ROIs were higher in suspected CIE cases (mean 543 ± 147 µg/cm3) compared to matched controls (mean 463 ± 141 µg/cm3; p = 0.01). Whole brain mean iodine concentrations were modestly higher in CIE patients compared to controls across all subgroups, without reaching statistical significance. CONCLUSIONS: CIE may be associated with modest increase in CT iodine concentration in the procedure vascular territory after neurointerventional procedures. The underlying pathophysiology of this condition remains uncertain and merits further investigation. KEY MESSAGES: Contrast-induced encephalopathy (CIE) is known as a rare neurologic condition following iodine contrast media use in neuroendovascular interventions, with unclear pathophysiology. WHAT THIS STUDY ADDS: This study provides evidence that suspected CIE is associated with higher cerebral iodine concentrations in affected vascular territories, a novel quantifiable change. Implications for research, practice, or policy: These findings suggest the potential for iodine concentration monitoring to refine CIE diagnosis and prevention strategies in clinical practice.

Angiographic Anatomy of the Middle Meningeal Artery in Relation to Chronic Subdural Hematoma Embolization.

PURPOSE: Middle meningeal artery (MMA) embolization is emerging as a potential treatment of chronic subdural hematomas (CSDHs). The purpose of this study is to describe MMA angiographic anatomy in relation to CSDH embolization. METHODS: This retrospective monocentric study was performed on imaging data of MMA embolization procedures for CSDH treatment performed between March 15, 2018 and April 30, 2020. Imaging data, including digital subtraction angiography (DSA) were reviewed independently by two physicians. Discrepancies were resolved by consensus. The MMA bifurcation pattern was analyzed according to an extended Adachi classification. Relations of the MMA with the ophthalmic artery (OA) were also analyzed. RESULTS: In this study, 140 MMAs were analyzed. Dominance of the anterior branch (type I) was observed in only 57/140 (41%) MMAs with a moderate interobserver agreement for classifying MMA into type I against all other (κ = 0.53, 95% confidence interval, CI 0.39-0.67). The posterior branch presented a proximal origin (type A), at the point of emergence of the MMA from the foramen spinosum or its immediate vicinity, in 48/135 (36%) MMAs with a very good interobserver agreement for classifying MMAs into type A against all other (κ = 0.82, 95% CI 0.72-0.92). An angiographic relationship with the OA was observed in 26 MMAs (19%). CONCLUSION: In the majority of CSDH patients both anterior and posterior branches of the MMA should be targeted to achieve extensive convexity devascularization. Frequent anatomical variations of the MMA with respect to emergence of the posterior branch and MMA orbital branches are expected to impact CSDH embolization strategy.

Direct puncture of the superficial temporal artery for ethylene vinyl alcohol embolization of a type 3 arteriovenous fistula with a dual lumen balloon.

Intracranial dural arteriovenous fistulas (dAVFs) may be difficult to treat by endovascular means, especially when the arterial feeders to the fistula are tortuous. 1 The usual main feeder to intracranial dAVFs is the middle meningeal artery, which may present very tight loops that are often difficult to cross with a microcatheter. 2 Direct puncture of a subcutaneous artery feeding the fistula indirectly via transosseous branches may be a valuable strategic option to overcome this limitation. 3 4 We report here the successful embolization of a Cognard type 3 parietal dAVF by direct puncture of the superficial temporal artery under roadmap guidance. The dAVF was subsequently embolized with ethylene vinyl alcohol via a dual lumen balloon, under balloon inflation. We highlight in this technical video 1 the potential difficulties and risks of direct puncture of the superficial temporal artery. We also stress the risk of delayed scalp necrosis using this technique. neurintsurg;13/5/493/V1F1V1Video 1.

Middle meningeal artery embolization reduces the post-operative recurrence rate of at-risk chronic subdural hematoma.

BACKGROUND: Embolization of the middle meningeal artery (MMA) has emerged as a potential treatment of chronic subdural hematomas (CSDHs). OBJECTIVE: To evaluate the impact on recurrence rate of postsurgical embolization of CSDH in patients with a higher than average risk of recurrence. METHODS: A monocentric retrospective study was performed on retrospectively collected data. From March 2018 to December 2019, embolization of the MMA was proposed as an adjunct postoperative treatment after burr-hole surgery in patients operated for a recurrent CSDH or a CSDH with an independent recurrence risk factor, including antiplatelet therapy, full anticoagulation therapy, coagulation disorder, hepatopathy, or chronic alcoholism. Patients who had undergone postoperative embolization were compared with a historic group of patients operated between March 2016 and March 2018, selected based on the same inclusion criteria. RESULTS: During the study period, 89 patients (with 74 unilateral and 15 bilateral CSDHs) were included and underwent an embolization procedure, leading to 91 out of a total of 104 MMA being embolized (88%). These were compared with 174 patients (138 unilateral and 36 bilateral CSDH) in the historic control group. One major procedure-related adverse event was registered. Four of the 89 patients (4%) required surgery for a CSDH recurrence in the embolization group, significantly less than the 24 of 174 patients (14%) in the control group (OR=0.28, 95% CI 0.07 to 0.86, p=0.02). CONCLUSIONS: Postsurgical embolization of the MMA may reduce the recurrence rate of CSDHs with a risk factor of recurrence.