Redukce radiační zátěže užitím fluoroskopické navigace při transpedikulární instrumentaci

HART, Radek, Martin KOMZÁK, R. BÁRTA, František OKÁL and E. SRUTKOVA. Redukce radiační zátěže užitím fluoroskopické navigace při transpedikulární instrumentaci (Reduction of Radiation Exposure by the Use of Fluoroscopic Guidance in Transpedicular Instrumentation). Acta Chirurgiae Orthopaedicae et Traumatologiae Čechoslovaca. 2011, vol. 78, No 5, p. 447-450. ISSN 0001-5415.

Basic information

• Original name: Redukce radiační zátěže užitím fluoroskopické navigace při transpedikulární instrumentaci
• Name (in English): Reduction of Radiation Exposure by the Use of Fluoroscopic Guidance in Transpedicular Instrumentation
• Authors: HART, Radek (203 Czech Republic, guarantor, belonging to the institution), Martin KOMZÁK (203 Czech Republic), R. BÁRTA (203 Czech Republic), František OKÁL (703 Slovakia) and E. SRUTKOVA (203 Czech Republic).
• Edition: Acta Chirurgiae Orthopaedicae et Traumatologiae Čechoslovaca, 2011, 0001-5415.

Other information

• Original language: Czech
• Type of outcome: Article in a journal
• Field of Study: 30211 Orthopaedics
• Country of publisher: Czech Republic
• Confidentiality degree: is not subject to a state or trade secret
• Impact factor: Impact factor: 1.628 in 2009
• RIV identification code: RIV/00216224:14110/11:00053752
• Organization unit: Faculty of Medicine
• UT WoS: 000297430200010
• Keywords in English: computer-assisted pedicle screw placement; spinal navigation; radiation exposure
• Tags: International impact

Abstract

Stabilizace thorakolumbálních pátečních segmentů pomocí fixace transpedikulárními šrouby doznala v posledních desetiletích značného rozšíření. Zavedení šroubů do pediklů může ovšem být relativně náročné. Peroperační radiologická kontrola v zadopřední a boční projekci je proto považována za "zlatý standard". Radiační dávky tak mohou značně narůstat. Uvedená práce předkládá výsledky užití fluoroskopické navigace při zavádění transpedikulárních šroubů s ohledem na dávky ionizujícího záření. Cílem bylo potvrdit nebo vyvrátit hypotézu, že fluoroskopická navigace umožňuje významnou redukci radiační zátěže při zachování stejného operačního postupu.

Abstract (in English)

The variability in width, height, and orientation of spinal pedicles makes pedicle screw insertion a delicate operation. Fluoroscopic guidance often exposes the patient and especially surgeons to relatively high doses of ionising radiation. The use of pulsed fluoroscopy is safer, as compared to continuous fluoroscopy, because of reduced radiation exposure. There are increasing numbers of literature reports regarding the high doses of radiation to which orthopaedic and spine surgeons are exposed during surgical procedures. Spine surgery can be associated with significant radiation exposure to the surgical staff. The purpose of this prospective study was to compare a computer-assisted navigation with a conventional procedure in order to assess if it is possible to reduce radiation exposure while preserving the accuracy of screw placement. MATERIAL AND METHODS The first conventional" group consisted of 30 patients, with an average of 1.9 segments of the lumbar spine stabilised. Screws were inserted transpedicularly under image intensifier guidance. In the second navigated" group of 30 patients, stabilisation of 1,8 segments was performed on average. A CT-free fluoroscopic 2D spinal navigation system (VectorVision, Brain LAB, Germany) was used intra-operatively. It combines image-guided surgery with C-arm fluoroscopy. For each surgery (navigated or not), the duration of irradiation was recorded. The irradiation duration was collected from the X-ray image intensifier. In both groups the screw positioning accuracy was controlled intra-operatively according to Learch's, Acikbas's, and Whitecloud s methods from AP and lateral images and by meticulous pedicle palpation. RESULTS The irradiation duration calculated to one vertebra (two screws) was significantly shorter in the second (navigated) group (3.4 s) than in the first (conventional) group (14.4 s). The mean duration of data registration was 6.0 minutes (range, 3 to 11 minutes). The mean ratio according to Acikbas s calculation method was 43.2 %) (range, 32 % to 74 %) in the first (conventional) group and 44.1 % (range, 35 % to 76 %) in the second (navigated) group. DISCUSSION During a conventional surgical procedure many X-ray images are made to control the accuracy of screw insertion. If the trajectory is not satisfying, it must be corrected or the pedicle is drilled again, always with a new fluoroscopic control. The process is repeated until satisfactory orientation is achieved. This is the explanation for a much longer duration of irradiation in conventional procedures. Navigation facilitates the surgical act, enabling us to acquire the right position of all screws, with only an AP image and a lateral image at the beginning of instrumentation for data registration; prolongation of the operative time is irrelevant. CONCLUSIONS Navigation allows us to keep the same accuracy of pedicle screw placement while reducing radiation exposure of the surgeons and operating room staff by about one quarter. In multiple-level vertebral instrumentations this reduction is more pronounced. In centres where many procedures involving spine instrumentation are done every day, the saved" exposure time can amount to hours.