COMPUTER-ASSISTED DESIGN AND ANALYSIS OF PEDICLE SCREW PLACEMENT BASED ON MEDICAL IMAGES OF THE SPINE

KNEZ, DEJAN (author), Vrtovec, Tomaž (mentor)

Medical imaging has become indispensable for healthcare and is nowadays used on a daily basis in clinical practice. Image information obtained during medical acquisition o_ers insight into the human body, which is otherwise invisible to human eyes, and therefore enables an objective interpretation of normal as well as pathological conditions of the human body, o_ers support to clinicians towards correct diagnoses and courses of treatment, and facilitates monitoring the development of diseases and treatment results. Although medical images acquired with stateof- the-art techniques enable an accurate insight into the structure of the human body, organs and tissues, clinicians are often hampered by the interpretation of the available image information. Therefore, methods for computer-assisted quantitative analysis and evaluation of medical images can provide a considerable support towards their reliable and reproducible interpretation. Chronic low back pain and musculoskeletal disorders are one of the main causes for visiting a doctor and starting a treatment, however, despite continual development of technologies and treatment procedures the current ways of treatment still do not provide satisfactory results. Therefore, segmentation of the obtained image information is essential to guide clinicians towards a proper treatment approach and course of a treatment, and, in the case of a surgical approach, to help surgeons to preoperatively plan the intervention. Pedicle screw placement surgery is currently the most widely used method in spine surgery for improving and, in the ideal case, eliminating a variety of pathological conditions of the spine, such as adolescent idiopathic scoliosis, kyphosis, degenerative disc disease and other instabilities of the spine. Accuracy of pedicle screw placement is directly related to the surgical outcome and therefore is of significant importance because a pedicle screw misplacement can lead to serious injuries. Over the past decades, image-guided pedicle screw placement techniques increased the accuracy of pedicle screw placement, which consequently reduced postoperative complications and resulted in a better surgical outcome, in comparison to the conventional free-hand placement technique. However, to take full advantage of image-guided techniques, preoperative pedicle screw placement planning should be performed, which is usually done manually on a preoperative computed tomographic image of the treated patient. To overcome manual planning, several computer-assisted methods have been proposed over the past decade, but do not address all important parameters for pedicle screw placement and have not been yet evaluated against real clinical data. The main contributions of this thesis are united under the design, development and validation of a computer-assisted method for preoperative pedicle screw placement planning based od parametric modeling of vertebral structures in three dimensions. The presented computer-assisted method is shown to be a valuable tool to overcome the time-consuming preoperative pedicle screw placement planning procedure. Moreover, the presented computer-assisted method addresses all important aspects that lead a spine surgeon towards a safe and reliable pedicle screw placement and therefore brings computer-assisted planning closer to the requirements of clinical practice.

• Language: English
• Keywords: medical image analysis pedicle screw placement computer-assisted preoperative planning pedicle morphometry pedicle modeling in 3D computed tomography images variability analysis spine surgery
• Work type: Doctoral dissertation
• Organization: FE - Faculty of Electrical Engineering
• Year: 2018
• PID: 20.500.12556/RUL-101519
• COBISS.SI-ID: 12080212
• Publication date in RUL: 13.06.2018

Secondary language

• Language: Slovenian
• Title: RAČUNALNIŠKO PODPRTO NAČRTOVANJE IN ANALIZA VSTAVITVE PEDIKULARNIH VIJAKOV NA PODLAGI MEDICINSKIH SLIK HRBTENICE

Abstract

V današnjem času je medicinsko slikanje nepogrešljivo v klinični praksi, saj pridobljena slikovna informacija nudi vpogled v pacientov organizem, ki je s prostim očesom sicer neviden. Slikovna informacija, ki je pridobljena tekom medicinskega slikanja, omogoča objektivno interpretacijo normalnih in bolezenskih stanj človeškega organizma, kar nudi podporo pri postavljanju pravilne diagnoze in poteku zdravljena oz. olajša spremljanje razvoja bolezni in rezultatov zdravljenja. Pri invazivnih pristopih se uporablja predvsem za načrtovanje samih posegov, kot sta npr. operativni poseg in radioterapija, medtem ko se pri neinvazivnih pristopih uporablja predvsem za postavljanje diagnoze in spremljanje poteka zdravljenja. Razvoj medicinskega slikanja temelji na odkritju nemškega fizika Wilhelma Conrada Röntgena iz leta 1895, ko je med proučevanjem katodnih žarkov zajel na detektorju še tedaj neznane žarke in jih posledično poimenoval žarki X (ang. X - rays). Nekaj tednov po odkritju je svetovni javnosti predstavil prvo rentgensko sliko (ang. radiograph) dlani svoje žene, na kateri so razvidne posamezne kosti ter prstan. To odkritje je vodilo do razvoja novih tehnik zajema medicinskih slik, kot sta računalniško tomografska (ang. computed tomography - CT) in magnetno resonančna (ang. Magnetic resonance - MR) slikovna tehnika. Obe slikovni tehniki nudita vpogled v človeški organizem skozi prereze, zaradi kakovosti informacije pa sta postali standard v klinični praksi.

• Keywords: analiza medicinskih slik vstavitev pedikularnega vijaka računalniško podprto predoperativno načrtovanje morfometrija pedikla modeliranje pediklov v 3D računalniško tomografske slike analiza variabilnosti operacija hrbtenice