S. Reinert

IMAGE-GUIDED NAVIGATION FOR MINIMAL INVASIVE APPROACHES IN CRANIOMAXILLOFACIAL SURGERY

The use of minimally invasive procedures in maxillofacial surgery will require new technologies involving surgical navigation and techniques. The aim of our studies is to improve the efficacy of image-guided navigation in combination with endoscopically assisted techniques for minimally invasive craniomaxillofacial procedures. Prospective evaluation was made of all patients who underwent surgical procedures using image-guided navigation. The most common type of operations performed were endoscopically assisted interventions within the paranasal sinuses, fracture treatment, the resection of bone lesions and further miscellaneous interventions. Our experience to date suggest that image-data based techniques are eminently applicable, providing a feasible alternative to conventional surgical treatment.

Significance of biodegradable implants in case of midfacial fractures.

The purpose of this prospective clinical study was to evaluate new resorbable implants for bone fixation. The plates and screws are made of poly (D, L)lactide (PDLLA). Bioresorbable osteosynthesis and fixation (ResorbX) has been applied in 22 patients. Indications for operations were craniofacial trauma (malar, orbital-floor or frontal bone fractures) or orthognathic procedures (Le Fort-I-osteotomies) as well as the surgical correction in case of craniofacial syndromes. In the initial follow up, the first patients showed clinically and radiologically uneventful fixation and healing of the bone. There were no implant material related complications. Overall, the advantages of PDLLA-implants appear to be their ease of use, radiolucency and resorption, although further experience is needed to determine the longterm benefits of biodegradable implants.

Intraoperative computertomographische Kontrolle im Rahmen der maxillofazialen Traumatologie unter Verwendung eines fahrbaren Scanners. Intraoperative CT Scans in Patients with Maxillofacial Trauma Using a Mobile Unit

Advances in intra-operative imaging and the development of new minimally invasive techniques are having an ever greater impact on modern surgery. Mobile CT scanners in the operating room is a new technique that permits image-guided surgery, and helps minimize postoperative complications. We report on our initial experience with intraoperative CT scanning during surgery on patients suffering lateral midface trauma. A mobile CT unit, the Tomoscan M (Philips, Utrecht, Netherlands) set up in the operating room, was evaluated in 6 patients with zygomatic bone fractures. The patients were placed on the CT scanner table, which is detachable from the gantry. The unit is powered by batteries charged from an ordinary ring mains supply via a conventional plug. The CT images obtained were of good quality in all cases. No technical problems were observed during surgery. Usng repeat CT scans, the procedure also permits accurate intraoperative monitoring of the anatomical repositioning of the bone fragments, and accurate implantation. No intraoperative or early postoperative complications were observed. This new technical aid ensures highly accurate reduction of the bone fragments, and minimizes the need for reoperation. High-quality intraoperative imaging with surgical navigation increase surgical outcome, and expand the spectrum of minimally invasive surgery.

Bilddatengestützte Navigation zur Steuerung der interstitiellen Lasertherapie von vaskulären Malformationen im Kopf- und Halsbereich / Image-guided Interstitial Laser Treatment of Vascular Malformations in the Head and Neck

Abstract Die interstitielle Neodym:YAG-Lasertherapie ist ein bewährtes Verfahren zur Behandlung von Hämangiomen, vaskulären Malformationen und verschiedenen Tumoren. Durch intraläsionale Applikation thermischer Laserenergie ist die regionale Destruktion von Geweben möglich. Die Einführung der Laserfaser erfolgt durch perkutane Nadelpunktion, eine visuelle Kontrolle der Plazierung und der Punktionsroute der Punktionsnadel ist nicht gegeben. Bei Patienten mit ausgedehnten vaskulären Malformationen im Kiefer- und Gesichtsbereich (fünf Prozeduren) wurden navigationsgestützte Punktionen zur interstitiellen Lasertherapie geplant und durchgeführt. Basierend auf fusionierten hochauflösenden Computer- und Kernspintomografie-Daten, wurde die Lasersonde mit einem speziellen Punktions- und Applikationsset sowie einem passiven optischen Navigationssystem in den jeweils geplanten Zielbereichen positioniert, und das Gewebe wurde lokal koaguliert. Durch die Anwendung der bilddatengestützten Navigation konnte die Lasersonde unter Schonung kritischer Strukturen sicher plaziert werden. Durch die Fusion der Bilddaten aus Computer- und Kernspintomografie konnte die Ausdehnung in Relation zur individuellen Anatomie intraoperativ für einen minimal-invasiven Zugang genutzt werden. Laser-induced interstitial thermal therapy (LITT) is a proven minimally invasive surgical technique for the treatment of haemangiomas and vascular malformations, and various tumours. The intra-lesion application of thermal energy destroys regional tissue. The percutaneous placement of the laser fibre for photocoagulation is done without the benefit of direct visual control. Image-data-based LITT was performed in patients (five procedures) with extensive venous malformations in the maxillofacial area. The system comprised a specially developed Nd:YAG laser fibre introducer set used in conjunction with fused high-resolution computed tomography, and magnetic resonance image-data--based surgical navigation. In all cases, follow-up examination clearly showed a diminishment in tumour volume, and all patients reported significant subjective improvement. The results suggest that navigation-guided LITT can be performed safely, preserving vital structures from collateral thermal damage.