A Novel Concept for Smart Trepanation

Abstract

Trepanation of the skull is a common procedure in craniofacial and neurosurgical interventions, allowing access to the innermost cranial structures. Despite a careful advancement, injury of the dura mater represents a frequent complication during these cranial openings. The technology of computer-assisted surgery offers different support systems such as navigated tools and surgical robots. This article presents a novel technical approach toward an image- and sensor-based synergistic control of the cutting depth of a manually guided soft-tissue-preserving saw. Feasibility studies in a laboratory setup modeling relevant skull tissue parameters demonstrate that errors due to computed tomography or magnetic resonance image segmentation and registration, optical tracking, and mechanical tolerances of up to 2.5 mm, imminent to many computer-assisted surgery systems, can be compensated for by the cutting tool characteristics without damaging the dura. In conclusion, the feasibility of a computer-controlled trepanation system providing a safer and efficient trepanation has been demonstrated. Injuries of the dura mater can be avoided, and the bone cutting gap can be reduced to 0.5 mm with potential benefits for the reintegration of the bone flap.

Piezosurgical treatment of crestal bone: quantitative comparison of post‐extractive socket outcomes with those of traditional treatment

“…The micrometric cut of ultrasound vibrations permits a precise, controllable cutting action (Rashad et al 2013), as also confirmed in morphological evaluation by scanning electron microscope study (Bauer & Romanos 2014). Piezosurgery technology works selectively on hard and soft tissues (Bovi et al 2010) and for this reason is frequently used in several bone surgery specialities such as Orthopaedics (Hoign e et al 2011), ENT (Grauvogel et al 2011), Neurosurgery (Follmann et al 2012) and Cranio and Maxillofacial Surgery (Robiony et al 2004).…”

Smart Trepanation System: Preclinical Analysis of Safety, Efficiency, and User Satisfaction

“…Based on the principle of synergistic cooperation, we developed a new concept, the Smart Trepanation System (STS). [6][7][8] It was developed to protect the dura mater and reduce the bone gap without disturbing the existing surgical workflow. The STS instrument is used freehand by the surgeon while automatically adjusting the cutting depth based on a preoperatively acquired computed tomography (CT) data set and the current position relative to the operation site tracked by a standard optical tracking system (►Fig.…”

“…The system uses a circular oscillating saw, which has a certain soft tissue preserving capability (2.5 mm) as an additional safety feature to reduce the risk of dural tears to a minimum. 7 The optimized parameter setting of oscillation frequency (10,000 rpm/minute), saw blade thickness (0.5 mm), stroke amplitude (1.5 mm), and saw blade contour was tested at different depths on an artificial skull model using bovine pericardium as a dura equivalent. Up to an overcutting depth of 1.5 mm, no damage occurred, and at a depth of 2.5 mm, only slight perforations at the surface of the pericardium occurred.…”

Analyse der Regelungsstrategien eines Osteotomie-Instruments auf Basis multimodaler Informationen / Analysis of the Control Strategies of an Instrument for Osteotomy on the Basis of Multimodal Information

“…Die intrinsisch weichgewebeschonende Eigenschaft des verwendeten Sägeverfahrens kann aufgrund der zirkularen Oszillation jedoch nur für kleine Überstände des Sägeblattes garantiert werden (ca. 2,5 mm) [6]. Hinzu kommt, dass die relevanten Weichgewebe (Hirngewebe oder Blutgefäße) druckempfindlich sind.…”

“…sensorgesteuerten Schnitttiefenregelung, die die Schnitttiefe der Säge durch ein sensorgestütztes automatisches Führungssystem an die jeweiligen ana- tomischen Gegebenheiten anpasst, soll es ermöglicht werden, den Knochen ohne eine Schädigung des darunter liegenden Weichgewebes zu durchtrennen. Die hierfür notwendigen Daten zur Entfernung des Säge-blatts von der unteren Knochen/Weichgewebe-Grenze können durch verschiedenartige Verfahren erfasst werden, beispielsweise Computertomographie, Ultraschall und Licht [4][5][6]. Fokus der in diesem Rahmen vorgenommenen Untersuchungen war die Bestimmung des maximalen Schnitttiefenfehlers dieser drei unterschiedlichen Ansätze in präklinischen Setups [4; 5].…”