Endonasale Entfernung eines ausgedehnten Kraniopharyngeomrezidivs mit Hilfe der intraoperativen Navigation

Intra-operative image update: first experiences with new software in computer-assisted sinus surgery

BACKGROUND

So far, conventional navigation systems do not provide the opportunity for any modification of acquired image datasets. In particular, the surgical progress in the operating field cannot be visualized unless new imaging scans are performed.

METHODS

In a feasibility study, new software creating intra-operative image updates by virtual means was tested in conjunction with conventional navigation. With this new software, surgically removed tissue volumes can be traced and viewed directly within the diagnostic image data.

RESULTS AND CONCLUSIONS

The new software represents an interesting and helpful amendment to conventional computer-assisted surgery in selected cases. During surgical procedures around bony structures, the surgeon gets an accurate virtual image update of the surgical progress in the operating field and the amount of tissue removed. However, in cases where mobile structures are present or soft tissue shifts are expected, this feature seems to be suitable only to a limited extent.

Navigationsunterstützte tumorfokussierte Chirurgie bei Schädelbasismalignomen

BACKGROUND

Multimodal strategies are required due to the poor prognosis for locally advanced frontal skull base tumors staged as T4. Therefore, a further increase in the degree of invalidity caused by therapy should be avoided, if possible, to preserve the quality of life. As the incidence of these tumors is low, there are no evidence-based, generally accepted therapeutic strategies.

METHODS

We evaluated the clinical results of three patients with extended frontal skull base malignomas staged as T4 tumors. The clinical course as well as the surgical technique were analyzed.

RESULTS

High dose neoadjuvant therapy for tumor downsizing was performed in all three patients within a multimodal therapy concept. The additional space for surgical manipulation close to the tumor borders, non-traumatically produced by tumor remission, permitted a safely navigated, controlled resection of the tumor under endoscopic or microscopic viewing using an approach associated with reduced trauma as "targeted surgery".

CONCLUSIONS

Surgical radicality is limited by the direct vicinity of locally progressive T4 tumors to the frontal brain and other vital structures. A controlled tumor downsizing allows the resection of such tumors using a minimally invasive approach assisted by instrumental navigation leading to less traumatization.

Der Einfluss der Navigation auf die endoskopische NNH-Chirurgie

BACKGROUND

Over the last few years, navigation systems have been used in endoscopic sinus surgery (ESS). We were interested determining whether this has repercussions on surgical procedures.

MATERIAL AND METHODS

From December 2003 to April 2006, we prospectively evaluated all navigated ESS procedures (Vector vision, Brain lab) by means of a questionnaire. Numerous data were determined including diagnosis, navigation benefit, difficulty of the operation, radiological score and complications.

RESULTS

Navigated ESS was carried out on 106 patients (54 male symbol; 52 female symbol, average age 55 years) with the following diagnoses: 59 chronic sinusitis with nasal polyposis (13 primary surgery, 46 revision surgery), 14 mucocele, 8 benign tumour, 10 malignant sinonasal tumour, and 15 other diseases. There was only a slight correlation between the difficulty of the operation and the use of navigation (r=0.51, P=0.00) and no significant correlation between the radiological score with chronic sinusitis and the use of navigation (r=0.22, P=1.23). On the other hand, we found a significant difference between the benefit of navigation using primary and revision functional ESS in cases of chronic sinusitis with nasal polyps (P=0.005). The degree of benefit of navigation for the different diagnoses was in descending order: recurrent polyposis, mucocele, osteoma, malignant tumors, polyposis (primary surgery) and inverted papilloma. Without navigation, 15 operations (14%) would not have been possible as an endonasal procedure, and 12 operations (11%) would not have been carried out thoroughly enough. In spite of navigation in three operations (3%) the endonasal approach had to be changed to a transfacial approach. Twelve slight and three serious complications (1 dura defect + pneumoencephalos, dura defect, meningitis without CSF leak) occurred.

CONCLUSIONS

Navigation exerts a substantial influence on the execution of the ESS by clearly extending its possibilities.