Ideal trajectory for frontal ventriculostomy: Radiological study and anatomical study

• Published in: Clinical neurology and neurosurgery 2022-06, Vol.217, p.107264-107264, Article 107264
• Main Authors: Vigo, Vera, Tassinari, Anna, Scerrati, Alba, Cavallo, Michele Alessandro, Rodriguez-Rubio, Roberto, Fernandez-Miranda, Juan Carlos, De Bonis, Pasquale
• Format: Article
• Language: English
• Subjects: Anatomy; Cadavers; Catheters; Freehand technique; Frontal ventriculostomy; Hydrocephalus; Kocher’s point; Medical imaging; Neurology; Neurosurgery; Perpendicular trajectory; Skull; Statistical analysis; Variance analysis; Ventricle
• ISSN: 0303-8467; 1872-6968
• DOI: 10.1016/j.clineuro.2022.107264

Several techniques have been described to improve the accuracy of the freehand procedure for frontal ventriculostomy and reduce complications due to suboptimal placement or misplacement of the catheter tip. To date, none of the available studies have found a reliable, low cost and consistent technique. We aimed to provide a standardized protocol for freehand frontal ventriculostomy. In the first part of the radiological study, 125 CT scans were used to measure the length of the catheter using 2 right-sided entry points. In the second part, a grid of 24 entry points on the frontal bone was used in 50 CT scans to record the distance from the cranial surface to the Foramen of Monro (FM). Ventriculostomy was performed on six cadaveric heads using a grid of 9 entry points, comparing a 5 ml syringe with the freehand technique to reach the target. The first part of the radiological study showed a length from the cranial surface to the FM was overall 67,38 ± 1,03 mm. For the second part, the mean length of the 24 selected points was 68,54 ± 2,73 mm without statistical difference. In the anatomical study, the FM was reached 8 times (14.8%) with the syringe vs 31 times (57.4%) with the freehand technique, and the ventricles 43 (79.6%) vs 37 (68.5%). The mean lengths from the skull to the FM were 71.33 ± 4.21 mm. In this study, we showed the optimal length of a frontal ventricular catheter. We have also demonstrated that the portion of the frontal bone above the superior temporal lines matches a sphere in which the center is the FM. •Catheter misplacement during frontal ventriculostomy is still a common complication.•Provide a standardized protocol for freehand frontal ventriculostomy without adding time and costs at the procedure.•Ideal length of the ventricular catheter is 67.38 ± 1.03 mm.•The frontal bone above the superior temporal lines matches a sphere which the center is the foramen of Monro.•Following a perpendicular trajectory, the foramen of Monro will always be detected from any point on the frontal bone.