OBJECTIVE: We wanted to evaluate the clinical value of intraoperative ultrasonography for real-time guidance when performing microneurosurgical resection of small subcortical lesions. MATERIALS AND METHODS: Fifty-two patients with small subcortical lesions were involved in this study. The pathological diagnoses were cavernous hemangioma in 25 cases, cerebral glioma in eight cases, abscess in eight cases, small inflammatory lesion in five cases, brain parasite infection in four cases and the presence of an intracranial foreign body in two cases. An ultrasonic probe was sterilized and lightly placed on the surface of the brain during the operation. The location, extent, characteristics and adjacent tissue of the lesion were observed by high frequency ultrasonography during the operation. RESULTS: All the lesions were located in the cortex and their mean size was 1.3 +/- 0.2 cm. Intraoperative ultrasonography accurately located all the small subcortical lesions, and so the neurosurgeon could provide appropriate treatment. Different lesion pathologies presented with different ultrasonic appearances. Cavernous hemangioma exhibited irregular shapes with distinct margins and it was mildly hyperechoic or hyperechoic. The majority of the cerebral gliomas displayed irregular shapes with indistinct margins, and they often showed cystic and solid mixed echoes. Postoperative imaging identified that the lesions had completely disappeared, and the original symptoms of all the patients were significantly alleviated. CONCLUSION: Intraoperative ultrasonography can help accurately locate small subcortical lesions and it is helpful for selecting the proper approach and guiding thorough resection of these lesions.
Adolescent ; Adult ; Aged ; Brain Diseases/*surgery/ultrasonography ; Brain Neoplasms/surgery/ultrasonography ; Female ; Glioma/surgery/ultrasonography ; Hemangioma, Cavernous, Central Nervous System/surgery/ultrasonography ; Humans ; Male ; *Microsurgery ; Middle Aged ; *Ultrasonography, Interventional ; Young Adult

BACKGROUNDThe goal of surgery in the treatment of intrinsic cerebral tumors is to resect the maximum tumor volume, and to spare the eloquent areas. However, it is difficult to discover the eloquent areas intraoperatively due to individual anatomo-functional variability both for sensori-motor and language functions. Consequently, the surgery of intrinsic cerebral tumors frequently results in poor extent of resection or permanent postoperative deficits, or both, and remains a difficult problem for neurosurgeons.

METHODSFrom January 2003 to January 2010, 112 patients with neuroepithelial tumors in/close to the eloquent areas were operated on under awake anesthesia with the intraoperative direct electrical stimulation for functional mapping of the eloquent areas. The extent of the tumors was verified by intraoperative ultrasonography. The maximal resection of the tumors and minimal damage of the eloquent areas were the surgical goal of all patients.

RESULTSTotally 356 cortical sites in 99 patients were detected for motor response by intraoperative direct electrical stimulation, 50 sites in 16 patients for sensory, 72 sites in 48 patients for language. Sixty-six patients (58.9%) achieved total resection, 34 (30.4%) subtotal and 12 (10.7%) partial. Fifty-eight patients (51.8%) had no postoperative deficit, while 37 patients (33.0%) had transitory postoperative paralysis, 26 patients (23.2%) with transitory postoperative language disturbance and 3 patients (2.7%) with permanent neurological deficits. No patient complained of pain recollection following operation.

CONCLUSIONSAwake anesthesia, intraoperative direct electrical stimulation and ultrasonography are three core techniques for the resection of intrinsic cerebral tumors near the eloquent areas. This new concept allows an improvement in the quality of surgery for neuroepithelial tumors in/adjacent to eloquent areas.

Adolescent ; Adult ; Aged ; Anesthesia ; methods ; Brain Mapping ; methods ; Brain Neoplasms ; diagnostic imaging ; surgery ; Deep Brain Stimulation ; methods ; Female ; Humans ; Male ; Middle Aged ; Neoplasms, Neuroepithelial ; diagnostic imaging ; surgery ; Ultrasonography