A new method to statistically describe microcatheter tip position in patient-specific aneurysm models

Abstract

Background and purposeEvidence on how to select microcatheters to facilitate aneurysm catheterization during coil embolization is sparse. We developed a new method to define microcatheter tip location inside a patient-specific aneurysm model as a 3-dimensional probability map. We hypothesized that precision and accuracy of microcatheter tip positioning depend on catheter tip shape and aneurysmal geometry.Materials and methodsUnder fluoroscopic guidance two to three operators introduced differently shaped microcatheters (straight, 45°, 90°) into eight aneurysm models targeting the anatomic center of the aneurysm. Each microcatheter position was recorded with flat-panel CT, and 3-dimensional probability maps of the microcatheter tip positions were generated. Maps were assessed with histogram analyses and compared between tip shapes, aneurysm locations and operators.ResultsAmong a total of 530 microcatheter insertions, the precision (mean distance between catheter positions) and accuracy (mean distance to target position) were significantly higher for the 45° tip (1.10±0.64 mm, 3.81±1.41 mm, respectively) than for the 90° tip (1.27±0.57 mm, p=0.010; 4.21±1.60 mm p=0.014, respectively). Accuracy was significantly higher in posterior communicating artery aneurysms (3.38±1.20 mm) than in aneurysms of the internal carotid artery (4.56±1.54 mm, p<0.001).ConclusionOur method can be used tostatistically describe statistically microcatheter behavior in patient-specific anatomy, which may improve the available evidence guiding microcatheter shape selection. Experience increases the ability to reach the intended position with a microcatheter (accuracy) that is also dependent on the aneurysm location, whereas catheter tip choice determines the variability of catheter tip placements versus each other (precision). Clinical validation is required.

New concept in neurovascular navigation: technical description and preclinical experience with the Bendit 17 and Bendit 21 microcatheters in a rabbit aneurysm model

“…[1][2][3] Furthermore, the most suitable microcatheter shape remains controversial. [4][5][6][7] In contrast with conventional microcatheters, which have a fixed shape and cannot be altered inside of the patient, bendable and steerable microcatheters allow the user to change the angle and shape of the tip in real time. Although large steerable catheters have been used for years in cardiovascular angiography, 8 9 only a few studies have discussed the potential benefits of steerable microcatheters in other applications, mostly in the liver and kidney.…”

“…Navigation through unfavorable vascular anatomy and unstable device delivery are common challenges for the endovascular treatment of intracranial aneurysms 1–3. Furthermore, the most suitable microcatheter shape remains controversial 4–7. In contrast with conventional microcatheters, which have a fixed shape and cannot be altered inside of the patient, bendable and steerable microcatheters allow the user to change the angle and shape of the tip in real time.…”

Computer-assisted microcatheter shaping for intracranial aneurysm embolization: evaluation of safety and efficacy in a multicenter randomized controlled trial

“…Microcatheter shaping is a fundamental aspect of aneurysm coiling 10–12. Microcatheters with well-designed shapes can be safely and precisely guided into aneurysms, remaining stable during aneurysm embolization.…”

Clinical experience with the Bendit steerable microcatheter: a new paradigm for endovascular treatment

“…Many types of microcatheters are used for the endovascular treatment of intracranial aneurysms, with no consensus about the ideal shape of a microcatheter for different procedures. [1][2][3][4] Compared with conventional microcatheters with a fixed shape, steerable microcatheters can bend or articulate, allowing fuller control over the placement of endovascular devices. [5][6][7][8][9][10][11][12] The Bendit steerable and bendable microcatheter (Bendit Technologies, Ltd., Petach Tikva, Israel) received Food and Drug Administration (FDA) clearance in 2019.…”

“…Many types of microcatheters are used for the endovascular treatment of intracranial aneurysms, with no consensus about the ideal shape of a microcatheter for different procedures 1–4. Compared with conventional microcatheters with a fixed shape, steerable microcatheters can bend or articulate, allowing fuller control over the placement of endovascular devices 5–12.…”