title: Why a Catheter Can Be Correctly Placed in the Anterior Horn of Lateral Ventricle by Inserting Perpendicular to the Frontal Bone on the Ventricular Drainage? Demonstration of the Accuracy of an Inserting Path by Computed Tomographic Image Study and Clinical Practices.
abstract: Why a catheter can be correctly placed in the ventricle by inserting perpendicular to the frontal bone on the ventricular drainage? We performed a study on the accuracy of a path perpendicular to the skull surface into the anterior horn using computed tomography (CT), and a clinical study. Twenty patients were studied on CT images. Using the curved multi-planar reconstruction method, the curved frontal skull and brain were reconstructed to flat structures, and perpendicular lines were drawn from the flat surface to the foramen of Monro on the reconstructed images. In clinical practice, we made a device which guided a catheter inserting perpendicular to the frontal skull surface, and used it in the ventricular drainage surgery for 148 hydrocephalic patients (158 surgeries). We discovered that the curved surface of the frontal bone around Kocher's point represents the surface of a globe (mean radius, 75.9 ± 4.3 mm) centering on the foramen of Monro. The distribution of points ranged from 13.5-43.5 mm (mean, 43.5 ± 6.1 mm) to the midline, with points appearing more laterally as ventricular size increased. A catheter was placed in the ventricle in 148 surgeries (99.4%), and the catheter reached the ventricle with correct orientation toward the foramen of Monro in 128 (81.0%). The reason why the ventricular insertion perpendicular to the frontal bone surface can provide a consistent path toward the foramen of Monro is that the curved surface of the frontal bone around Kocher's point represents the surface of a globe centered on the foramen of Monro.
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Kiyonobu
authors.initials: K
authors.lastname: Ikeda
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Takashi
authors.initials: T
authors.lastname: Asahi
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Takaaki
authors.initials: T
authors.lastname: Iida
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Jiro
authors.initials: J
authors.lastname: Yamamoto
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Tsuyoshi
authors.initials: T
authors.lastname: Tsukada
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Nobutaka
authors.initials: N
authors.lastname: Yamamoto
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Fumihiko
authors.initials: F
authors.lastname: Takeuchi
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Shigeru
authors.initials: S
authors.lastname: Munemoto
authors.affiliation: Department of Neurosurgery, Kanazawa Neurosurgical Hospital.
authors.forename: Shu-Ji
authors.initials: SJ
authors.lastname: Sato
authors.affiliation: Department of Neurosurgery, Kanazawa Medical Center.
authors.forename: Shuichi
authors.initials: S
authors.lastname: Akaike
authors.affiliation: Department of Neurosurgery, Kanazawa Medical Center.
authors.forename: Katsuo
authors.initials: K
authors.lastname: Shoin
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D002404:Catheterization; D002557:Cerebrospinal Fluid Shunts; D002648:Child; D005624:Frontal Bone / Q000000981:diagnostic imaging; D006801:Humans; D006849:Hydrocephalus / Q000000981:diagnostic imaging* / Q000601:surgery*; D020547:Lateral Ventricles / Q000000981:diagnostic imaging / Q000601:surgery*; D008875:Middle Aged; D010818:Practice Patterns, Physicians'; D015203:Reproducibility of Results; D014057:Tomography, X-Ray Computed; D055815:Young Adult
keywords: frontal bone; guide; ventricular tap