V.E. Parfenov, G.E. Trufanov, D.V. Svistov, A.V. Savello, R.A. Lapshin, A.V. Tsibirov
Clinic of Neurosurgery, Medicomilitary Academy, Saint Petersburg, Russia
We carried out retrospective analysis of 80 operations with the purpose of comparing different methods of neuronavigation, determining their potentialities in surgical treatment of brain tumors, developing methods of preoperative marking and intraoperative navigation. Patients with intracranial tumors were operated in the Clinic of Neurosurgery of the Medicomilitary Academy in 2002-2004. There were 45 males and 35 females, aged 29-77. A mean age was 44 years.
All the patients were divided into 2 groups. The main group consisted of 57 cases, who were operated with use of different methods of intraoperative navigation. They were as follows: ultrasonic navigation with applying the Sonoline Elegra apparatus (Siemens) (57 cases) and sonographic navigation in combination with MRI- or CT-navigation and applying StealthStation TreonTM (Medtronic) (11 cases).
The control group was represented by 23 patients, treated during the same period without neuronavigation.
Primary operations were performed in 73 cases (91%). Interventions for a prolonged growth were made in 7 patients (9%). Osteoplastic and decompressive trephination was performed in 66 (82%) and 14 (18%) of cases respectively. Operations consisted in total, subtotal (more than 75%) and partial (50-75%) removal of a tumor.
Intervention effectiveness in the main group was as follows: total removal - 27 cases (27%), subtotal removal - 16 cases 29%) and partial removal - 14 cases (24%).
As for the control group total, subtotal and partial removals were performed in 10 (42%), 5 (25%) and 8 (33%) cases respectively.
Efficacy of surgical treatment was controlled by intraoperative ultrasonic scanning and postoperative CT- and MRI-examinations of the brain with I/V enhancing.
Our experience shows, that use of the StealthStation navigaton system and intraoperative sonography allowed to make planning of intervention much easier, to lessen a degree of surgical trauma of the brain, to reduce time of surgical intervention and to increase its efficacy. The StealthStation navigaton system permitted to optimize a surgical approach, dimensions and localization of a trephination hole and to minimize a risk of damaging intact zones and cerebral vessels by performing operations with a keyhole-like approach.
It was demonstrated, that complex use of different methods of neuronavigation was of particular importance during removal of intracerebral tumors with a marked cystic component, when emptying of a cyst content often resulted in loss of neuronavigation landmarks. Intraoperative neurosonography made it possible to correct data of a navigation pattern and to estimate operation efficacy.
Potentialities of neuronavigation allowed to widen indications for removal of small or multiple deep-lying mass lesions.
Thus, our experience shows, that a combination of neuonavigation with MRI- or CT- navigation is justified, as it improves results of surgical treatment of patients with intracranial tumors.