[Application of intraoperative ultrasound combined with neuronavigation for resection of intracranial cavernous malformations in minimally invasive neurosurgery].

OBJECTIVES: To analyze the reliability and clinical value of intraoperative ultrasound combined with neuronavigation for resection of intracranial cavernous malformations. METHODS: From January 2007 to December 2009, 40 cases of intracranial cavernous malformations were operated under the application of intraoperative ultrasound combined with neuronavigation. There were 18 male and 22 female, aged 18 to 58 years, with a mean age of 34.5 years. Neuronavigation was used for all patients before operation to display the three-dimensional model of nervous system and lesions, so to design the operative approach and determine the scope of the incision. Lesions were allocated by real-time neuronavigation in order to continuously verify the accuracy of operative approach during the operation, supplemented by real-time monitoring of intraoperative ultrasound to guide the process of surgery and determine the extent of resection of lesions. RESULTS: The registration error of neuronavigation was 1.3 - 3.2 mm, with an average of 2.0 mm. All the patients' three-dimensional model of nervous system and lesions were satisfactorily displayed, and the area of lesions were all accurately located. Structural brain-shifts occurred in 4 cases in the remove process of the lesion, with shift degree 5.0 - 10.0 mm, and were corrected by intraoperative ultrasound. All lesions were well displayed by intraoperative ultrasound. Gross total resection was achieved in all patients, with no patient infected or dead. Neurological deterioration was seen in 2 patients, the morbidity was 5.0%. CONCLUSIONS: The combination of neuronavigation and intraoperative ultrasound for resection of intracranial cavernous malformations can provide valuable intraoperative informations of the location and resection level of the lesion, thereby maximize the accuracy of lesion localization and the extent of resection, with less complications and enhanced efficacy of the surgery.

[Microsurgical treatment of adult craniopharyngiomas in 156 cases].

OBJECTIVE: To explore the clinical features, surgical approaches and outcomes of craniopharyngioma in adults. METHODS: A total of 156 cases of adult craniopharyngioma underwent microsurgery at our hospital were retrospectively reviewed and classified into four types according to the location of tumor relative to sellar diaphragm and the third ventricle. They were divided into four groups: intrasellar type (n = 6), suprasellar & extraventricular type (n = 59), intraventricular type (n = 63) and mixed type (n = 28). Unilateral subfrontal approach was chosen in 9 cases, anterior interhemispheric approach in 14 cases, pterional approach in 102 cases, transcallosal approach in 28 cases and transsphenoidal approach in 3 cases. RESULTS: Tumors were totally removed in 124 cases (79.5%), subtotally removed in 25 cases (16%) and partially removed in 7 cases (4.5%). Two patients died after surgery. Pituitary stalk was identified and protected intraoperatively in 69 cases, and postoperative diabetes insipidus occurred in 109 cases. The follow-up period ranged from 3 months to 5 years. 75.3% of the cases were capable of normal work and life and tumor recurred in 26 cases. CONCLUSION: Selection of appropriate approach is the key to successful microsurgery for craniopharyngioma according to the site and growth pattern of tumor.

[Value of intra-operative ultrasound in detecting the boundaries of intra cranial gliomas].

OBJECTIVE: To evaluate the application of intra-operative ultrasound (IOUS) in detecting the boundaries of intracranial gliomas. METHODS: One hundred and five consecutive patients with supra-tentorial glioma were included, male: 42 cases, female: 46 cases, age ranged from 15 - 67 years (mean 41 yrs), intra-operative ultrasound B was used to detect tumour boundaries before and after resection in 88 cases, tissues with suspicious echo was taken for verification by histological examination. And repeated MRI scan was received within 3 day after operation to judge the resection extent. The result was judged by Ultrasound doctor, neurosurgeon and pathologist, respectively. RESULTS: Eighty-eight patients were operated assisted by IOUS B. Tumour was nearly total removed in 83 cases and subtotal removed in 5 cases. Histological examination showed WHO Grade II 30 cases, Grade III 31 cases and Grade IV 27 cases. One hundred and twenty samples were taken and 101 were verified as tumours. And residual tumours were found in 17 cases and brain contusion and laceration was found in 1 case. The sensitivity of IOUS was 80.1% and the specificity was 69.8%. CONCLUSIONS: IOUS could produce a marked effect in judging boundaries of glioma, especially in low grade gliomas. IOUS could be a routine technique in intracranial glioma operation.

[Application of individually designed trans-fissure approach in brain surgery: analysis of 90 cases].

OBJECTIVE: To explore the feasibility and value of trans-fissure approaches in brain surgery through individually designed craniotomy. METHODS: Ninety patients with intracranial space-occupying lesions, 47 males and 58 females, aged (43 +/- 14) (1 - 68), were treated by individualized trans-fissure approach surgeries. Linear scalp incision or "horseshoe shape" scalp incision were designed to perform the operation, with a bone flap 3 - 4 cm in diameter. The shortest approach to reach the lesion was decided under the guidance of neuro-navigation and real-time B-mode ultrasonography. Then the lesions were removed through natural cortical fissures. Another 79 patients with intracranial space-occupying lesions, 53 males and 51 females, aged (42 +/- 11) (15 -73), undergoing classical surgeries in the same period were used as control group. The average operation time, size of bone flap, amount of blood loss, hospitalization time, and hospitalization cost were compared between these 2 groups. RESULTS: The operation time of the individually designed trans-fissure approach group was (3.1 +/- 1.6) hours (1.33 - 10.83 hours), significantly shorter than that of the control group [(4.8 +/- 1.9) hrs, P < 0.05]. The amount of blood loss of the individually designed trans-fissure approach group was (173 +/- 168) ml (20 m - 500 ml), significantly less than that of the control group [(410 +/- 61) ml, P < 0.01]. The size of bone flap of the individually designed trans-fissure approach group was (12 +/- 5) cm2 [(1 - 25) cm2], significantly smaller than that of the control group [(20. +/- 9) cm2, P < 0.01]. Four of the 90 patients of the individually designed trans-fissure approach group received retransfusion, compared to 15 in the control group, during operation. No infection or other significant complications occurred after operation in the individually designed trans-fissure approach group. The hospitalization time of the individually designed trans-fissure approach group was (20 +/- 6) days (9 - 39 days), significantly shorter than that of the control group [(24 +/- 7) days, P < 0.01]. The average hospitalization cost of the individually designed trans-fissure approach group was (23171 +/- 7280) yuan RMB; significantly lower than that of the control group [(28096 +/- 10822) yuan, P < 0.01]. CONCLUSIONS: One of the land markers of minimally invasive neurosurgery, individualized trans-fissure approach has been proved to be an effective minimally invasive approach that leads to better outcome and fewer complications after operation.

Intraoperative contrast-enhanced ultrasound for brain tumors.

OBJECTIVE: The purpose of this study was to investigate the feasibility and value of the intraoperative contrast-enhanced ultrasound (CEUS) in resection for brain tumors. MATERIALS AND METHODS: Intraoperative CEUS was performed in 29 patients with brain tumors pre-resection, in whom 9 (of 29) patients underwent second intraoperative CEUS for assessing remained tumor tissue after initial resection. Gray-scale and color-flow images of the brain tumors on both conventional and CEUS were analyzed and compared with the results of surgical pathology. RESULTS: The border of the tumor and remained tumor tissue was more distinguishable from healthy brain on CEUS than that on conventional ultrasound during the operation. Improving definition of the tumor tissue from normal brain with CEUS was demonstrated in all cases. CONCLUSION: Intraoperative CEUS has the potential to be a very useful imaging technique not only in defining the border between the tumor and healthy brain pre resection but also in detecting remained tumor tissues after the initial resection.

Treatment of alternated water-electrolyte balance and endocrine status after removal of craniopharyngioma in adults.

BACKGROUND: Water-electrolyte disturbance and endocrine alterations are common complications of adult patients with craniopharygioma in the postoperative period and may affect their recovery and prognosis. Some of these complications even lead to death. Appropriate remedy based upon the status of water-electrolyte balance and the endocrine system is essential to good therapeutic results of adult patients with craniopharyngioma. METHODS: The alterations in water-electrolyte balance (117 patients) and endocrine status (42) of adult patients with craniopharyngioma after surgery were analyzed retrospectively. RESULTS: Most patients with craniopharyngioma experienced postoperative water-electrolyte disturbances and hypotonic dehydration. Moreover, the incidences of hypothyroidism and hypoadrenocorticism were relatively high. CONCLUSION: It is critical to deal with dehydration and endocrine disorders for a sound outcome of craniopharyngioma surgery.

[Ultrasound-guided minimally invasive neurosurgery in treatment of cranial tumors: clinical study].

OBJECTIVE: To explore the applicability of ultrasound-guided minimally invasive neurosurgery in treatment of intracranial tumors. METHODS: Thirty five patients with intracranial tumors diagnosed with preoperative CT and MRI underwent craniotomy. Intraoperative real-time monitoring ultrasound was conducted to detect the location, size and depth of the cerebral masses so as to determine the appropriate approach. At the end of operation, ultrasonography was used to explore the range of residue tumors. RESULTS: All the 35 patients acquired exact location of the tumors with ultrasound manifesting different levels of echo. According to the pathological results, the lesions of 32 patients (91%) were totally removed and 3 patients (9%) underwent subtotal resection. No infection was found. CONCLUSION: Ultrasound-guided minimally invasive neurosurgery is an effective real-time tool to localize brain tumors. It will provide a significant guidance for minimally invasive neurosurgery.

[Application of diffusion tensor imaging fractography in minimally invasive surgery of brain tumors].

OBJECTIVE: To investigate the effects and prospect of application of diffusion tensor imaging (DTI) fractography in minimally invasive surgery of brain tumors. METHODS: DTI fractography was performed in 52 patients with malignant brain tumors. Based on the DTI fractography results, 34 of the 52 patients underwent operation under neuro-navigation, and 18 of the 52 patients underwent operation routine minimally invasive craniotomy and tumor resection without neuro-navigation. RESULTS: The rate of total tumor resection was 86.5% (45/52). The mortality was 1.9% (1/52). The disability rate was 11.5% (6/52). No case needed the second operation. CONCLUSION: DTI fractography has raised the minimally invasive neurosurgery to the level of protecting the nuclei and nerve tracts and guiding intra-operative management of infiltration of deep-seated tumors, especially when combined with neuro-navigation and interventional MRI.

Clinical and pathological characteristics of septum pellucidum tumor and choice of surgical approaches for its resection.

BACKGROUND: Tumor involving the septum pellucidum is uncommon. Surgery as the main therapeutic procedure for this lesion is a challenge to neurosurgeons. We analyzed the clinical characteristics and pathological features of septum pellucidum tumor in 41 patients and compared the curative effects of frontal transcortical, trans-sulcal and interhemispheric transcallosal approaches. METHODS: Clinical characteristics and the pathological features of septum pellucidum tumor were investigated retrospectively in 41 patients. The differences in postoperative residual rates, extents of tumors and resection of normal brain tissues after use of the three approaches in these patients were analyzed statistically. RESULTS: Septum pellucidum tumor is more likely to attack young or middle-aged persons. The tumor mainly presents itself as a central neurocytoma or cerebral low-grade glioma in pathology and manifests as intracranial hypertension clinically. No difference was found in the extent of tumor resection but significant difference in the extent of normal brain tissue resection and in postoperative disability rate among the three approaches. The transcortical approach brought about the most serious injury to brain tissue and the highest disability rate, Whereas the frontal transcallosal approach the lightest injury and the lowest disability rate. The injury to brain tissue and the disability rate brought about by the front trans-sulcus approach were between the above two approaches. CONCLUSIONS: Operation is still regarded the major treatment for septum pellucidum tumor. Transcallosal and trans-sulcus approaches are fit with the concept of minimally invasive surgery, and transcallosal approach is the first choice for septum pellucidum tumor.

[Photodynamic diagnosis and fluorescence-guided resection of malignant gliomas: a report of 15 cases].

OBJECTIVE: To study the usefulness of the intraoperative photodynamic diagnosis (PDD) and fluorescence-guided resection of malignant gliomas. METHODS: Fifteen consecutive patients with malignant gliomas received doses of hematoporphyrin derivative (HPD, 2 mg/kg body weight) 48 hours before induction of anesthesia. After the tumors recognized by bare eyes they were removed routinely. The fluorescence around 690 nm excited by laser beam (wavelength 632.5 nm) was detected by laser electronic spectrum analyzer and then fluorescing tissue was removed whenever it was considered safel. Tissue samples derived from the walls of tumor cavities after resection and PDD were sent for histological examination. Compared with the result of the histological examination, the sensitivity and specificity of PDD were calculated and recorded. Early postoperative MRI or CT were done to determine the extend of the resection of the tumors. Surgical mortality and morbidity were also recorded. RESULTS: Intraoperatively, in all of 15 cases tumor areas with HPD fluorescence could be recognized by laser electronic spectrum analyzer. On the basis of 106 tissue samples derived from 15 tumors, a sensitivity of 90.6%, a specificity of 96.8% and an accuracy of 94.3% of PDD were achieved. In 2 cases the resection of residual tumor were performed after finding left tumors by PDD. Complete resection of contrast-enhancing tumor was accomplished in 9 patients (60%). Residual intraoperative tissue fluorescence left unresected for safety reasons predicted residual enhancement on MR images in 5 of the 6 remaining patients. No perioperative deaths and one case of morbidity were encountered. CONCLUSIONS: Intraoperative photodynamic diagnosis following resection of malignant gliomas can detect residual tumor tissue with high accuracy. Photodynamic diagnosis and fluorescence-guided resection of malignant gliomas have a positive role in improving the radicality of malignant glioma resection.

The supraorbital keyhole approach with eyebrow incisions for treating lesions in the anterior fossa and sellar region.

BACKGROUND: Keyhole surgery has developed since the 1990s as a less invasive therapeutic strategy for intracranial lesions, initially for the treatment of intracranial aneurysms. The purpose of this study was to describe and evaluate the results of surgical treatment of lesions in the anterior fossa and sellar region via a supraorbital keyhole approach using eyebrow incisions. METHODS: Between April 1994 and July 2003, 54 patients with lesions in the anterior fossa and sellar region were operated on via the supraorbital keyhole approach. The surgical results were studied retrospectively and compared with that of patients with lesions at the same locations but treated via a conventional subfrontal approach. RESULTS: No significant difference in curative effect was found between the conventional subfrontal approach and the supraorbital keyhole approach. However, the supraorbital approach required a much smaller skin incision, causing less surgical trauma, while achieving excellent surgical exposure and good recovery. CONCLUSION: The supraorbital keyhole approach using an eyebrow incision is safe, effective, and both suitable and convenient for treating lesions in the anterior fossa and sellar region, with almost no adverse consequences on the facial features of patients.