Efficacy of gamma knife surgery for control of peritumoral oedema associated with metastatic brain tumours

OBJECTIVES

To evaluate the efficacy of gamma knife surgery (GKS) for the control of peritumoral oedema associated with metastatic brain tumours.

METHODS

A retrospective study of 280 consecutive metastatic brain tumours-100 from lung cancers, 100 from breast cancers and 80 from renal-cell carcinomas, associated with peritumoral oedema. The peritumoral oedema index was measured as A*B*C, where A (cm) was the maximum diameter of peritumoral oedema on the axial image, B (cm) was the maximum diameter perpendicular to A, and C (cm) was the maximum diameter on the coronal image.

RESULTS

The oedema index of the renal cancer metastases was significantly larger than those of lung and breast cancer metastases (p<0.01). The oedema index of the renal cancer metastases at final imaging was also larger than those of lung (p<0.05) and breast (p<0.01) cancer metastases. The delivered marginal dose (22 Gy or more) was significantly correlated with tumour growth control by multivariate analysis (p = 0.03). Primary site (renal or not renal: p<0.01) and delivered marginal dose (25Gy or more: p = 0.04) were significantly correlated with control of peritumoral oedema by multivariate analysis.

CONCLUSIONS

Brain oedema around metastatic brain tumours from renal-cell carcinomas was more extensive at the time of GKS and at final imaging compared with lung and breast cancer metastases. This paper suggests that the optimal doses for tumour growth control and brain oedema control may differ for metastatic brain tumours from renal-cell carcinomas.

Microsurgery for vestibular schwannoma after gamma knife radiosurgery

BACKGROUND

We evaluated the clinical characteristics of microsurgery for vestibular schwannoma (VS) after failed gamma knife radiosurgery (GKS).

METHOD

Twelve patients, 5 men and 7 women aged 19 to 70 years (mean 54.5 years), who underwent microsurgery after failed GKS for VS were studied retrospectively.

FINDINGS

The median interval between GKS and microsurgery was 28.8 months (range, 6.6-120 months) and 4 patients had undergone previous microsurgery. The mean volume of tumour at GKS was 6.9 cm(3) (range, 0.5-19.7 cm(3)) and the mean prescription dose to the tumour margin was 12.3 Gy. Microsurgery involved the lateral suboccipital approach in all patients. Tumour expansion involved solid enlargement in 7 patients, cystic enlargement in 3, and central necrosis in 2. Bleeding was slight in all patients except in one, probably because of the previous irradiation. Adhesion to the brain stem was severe in 7 patients. Identification of the facial nerve was easy in 5 operations and difficult in 7. Dissection of the tumour from the facial nerve was difficult in most interventions because of severe adhesions or colour change. Severe adhesions between the trigeminal nerve and the tumour was observed in 2 patients. The tumour was subtotally removed except around the internal auditory canal in most patients. Only one residual tumour increased in size and needed second GKS. The function of the facial nerve deteriorated in 3 patients, was unchanged in 7, and improved in 2. All patients had lost hearing on the affected side at the time of microsurgery.

CONCLUSIONS

Microsurgery for VS after failed GKS presents some technical difficulties. Dissection of the tumour from the facial nerve or brain stem is likely to be difficult. We recommend subtotal resection without dissection of the facial nerve and tumour, because growth of the residual tumour was rare in our series.

Gamma knife radiosurgery for intracranial haemangioblastomas

BACKGROUND

The results of gamma knife radiosurgery for haemangioblastomas were retrospectively studied to assess the efficacy for tumour growth control and clarify the clinical indications for gamma knife radiosurgery in these tumours.

METHODS

The medical records of 22 patients with 67 tumours, 12 men and 10 women aged 20-73 years (mean 51.9 years), who underwent gamma knife radiosurgery for haemangioblastomas between January 1993 and January 2006, were retrospectively reviewed. Ten patients with 54 lesions had von Hippel-Lindau disease. The mean tumour volume was 1.69 cm(3) (range 0.0097-16.4 cm(3)). Nineteen patients had undergone 1-4 open surgery procedures (mean 1.5) before gamma knife radiosurgery. Tumours without a cystic component, (the solid type), were found in 54 lesions and tumours associated with cyst, (the mural nodule with cyst type), in 13 lesions. The marginal dose was 8-30 Gy (mean 14.0 Gy).

FINDINGS

Follow-up magnetic resonance (MR) imaging was performed at 9-146 months (mean 63 months). The control rate for tumour growth was 83.6%. The only factor affecting tumour growth control was the presence of a cystic component at the time of gamma knife radiosurgery in both univariate and multivariate analysis. No complication such as radiation-induced peritumoural oedema or radiation necrosis occurred.

CONCLUSION

The presence of cystic components at the time of gamma knife radiosurgery was the only factor significantly correlated with unfavourable tumour growth control by gamma knife radiosurgery for haemangioblastomas. Gamma knife radiosurgery is effective for solid type tumours, even if the marginal dose is relatively low. Surgical removal is recommended for mural nodule with cyst type tumours, when possible.

Repeated gamma knife radiosurgery for multiple metastatic brain tumours

BACKGROUND

The effectiveness of repeated gamma knife radiosurgery (GKS) for the treatment of multiple metastatic brain tumours was evaluated.

METHODS

This study included 16 patients with 242 tumours, 10 men and 6 women with a mean age of 60.3 years at initial GKS, who underwent GKS four times or more for newly developed metastatic tumours.

FINDINGS

Sixteen patients underwent a total of 83 GKS procedures (range 4 to 8, mean 5.2). The mean number of metastases at each GKS procedure was 2.9 and the number of tumours tended to increase at the 5th GKS procedure compared with the 1st, but not significantly. The mean interval between each procedure was 4.8 months and was not significantly different. Median survival was 22.4 months (range 9.4-78.9 months) and the primary site was not correlated with survival time. The total number of treated tumours tended to correlate to survival time, but not significantly. Use of adjuvant whole brain radiation also had no significant effect on survival time. The Karnofsky performance status was maintained at more than 70 in most patients, but decreased significantly between initial and final GKS. Death due to progression of brain lesions occurred in only about 30% of patients regardless of the multiple newly developed brain metastases.

CONCLUSIONS

Repeated radiosurgery for brain metastases is effective and relatively long survival can be expected in some patients associated with a low risk of radiation-induced injury.

Gamma knife radiosurgery for metastatic tumours in the brain stem

BACKGROUND

Stereotactic radiosurgery has become important in the treatment of metastatic brain tumours and is often the first choice modality for eloquent or deep locations such as the brain stem. This study evaluated the efficacy of gamma knife radiosurgery (GKS) for the treatment of brain stem metastases.

METHODS

The medical records of 25 patients with 31 tumours, 11 men and 14 women aged 42 to 78 years (mean 57.1 years), who underwent GKS for metastatic tumours in the brain stem were retrospectively reviewed. The results of GKS were evaluated according to the change in tumour size on neuro-imaging.

FINDINGS

The most common location of the primary malignancy was the lung followed by the breast. Adenocarcinoma was found in 19 patients (24 lesions). No case of squamous cell carcinoma was found. The mean calculated tumour volume was 2.1 cm(3) and the mean prescription dose to the tumour margin was 13.0 Gy. Mean duration of neuro-imaging follow up was 5.2 months and the overall tumour control rate was 77.4%. There was a significant correlation between the marginal dose delivered and the effect on neuro-imaging. New radiation-induced injury in the surrounding brain occurred in only 2 patients.

INTERPRETATION

GKS for brain stem metastases using a marginal dose of 15 Gy or less is effective and relatively safe. Accurate targeting of the tumour and safe dose planning are essential to obtain satisfactory results with GKS for brain stem metastases.

[A case of a lumbar spinal synovial cyst located on the midline]

We report a case of lumbar spinal synovial cyst located on the midline. A 72-year-old man was admitted to our hospital with the chief complaint of low back pain radiating to the left buttock and posterior thigh. An MR image revealed an extradural cystic lesion adjacent to the dorsal side of the dural sac at the L4-5 level. The cyst was remote from the facet joints and existed on the midline just in front of the L4 lamina. A CT scan showed a concave deformity of the ventral aspect of the L4 lamina because of compression by the cyst. The patient underwent L4 laminectomy and total removal of the cyst. The cyst was in contact with the anterior surface of the ligamentum flavum and it had no connection with the facet joint. In the histological examination, the cyst was multilobular and lined with synovial epithelium. Therefore the cyst was diagnosed as a synovial cyst. After the operation, the pain radiating to the buttock and thigh completely disappeared. Intraspinal synovial cysts are usually located in the lower lumbar spine and most of them are adjacent to the facet joint. The cysts that are located on the midline are very rare. We review previous reports and discuss clinical and pathological features of spinal synovial cysts.

[A case of cervical liquorrhea with headache in and around the area of the great occipital nerve]

We report a 44-year-old man who had sudden-onset severe pain with ardor at the left occipital and nuchal region without trauma in July, 1992. Severe pain disappeared soon after, but dull pain continued intermittently. Four months later, he was referred to our hospital. Neurological examination showed no abnormalities. Cervical CT scan and myelography disclosed liquorrhea. Digital subtraction myelography confirmed cerebrospinal fluid leakage from the level of C1/2 disc. He underwent laminectomy of C1 and C2, and dural plasty on April 6, 1993 with subsequent disappearance of headache. We suppose that this headache was due to rupture of the root sleeve and compression to the root and dorsal root ganglia by outflowed liquor.

[Glioblastoma multiforme with liver metastasis--case report]

Extracranial metastasis of glioblastoma is rare. This is an autopsy case report of a patient with glioblastoma multiforme found to have metastasized to the liver. A 42-year-old woman was admitted with a chief complaint of headache. Physical and neurological examinations on admission showed no abnormalities. CT and MRI demonstrated a tumor in the left parietooccipital region with invasion into the subependymal area of the left lateral ventricular trig-one. A cerebral angiogram showed tumor staining in the same area. Subtotal tumor resection was performed uneventfully. The microscopic diagnosis was glioblastoma multiforme. Postoperatively, the patient underwent whole brain and local irradiation, and intra-arterial ACNU infusion therapy. One month later, she developed low back pain, probably due to spinal dissemination. Postmortem examination showed local recurrence of the tumor and subarachnoidal dissemination not only in the base of the skull but in the lower spinal cord. Tumor was also observed in the liver, but no lung or lymph node metastasis was detected. Metastasis to the liver in this patient is believed to have occurred via the anastomosis between the vertebral and portal venous system.

Thrombotic occlusion of the middle cerebral artery

BACKGROUND AND PURPOSE

Epidemiological study of middle cerebral artery occlusion is important because the indication for extracranial-intracranial arterial bypass remains in dispute. To help clarify this issue, we investigated the prognosis of thrombotic middle cerebral artery occlusion in Japanese patients.

METHODS

We studied 40 patients with thrombotic middle cerebral artery occlusion who were selected on the basis of clinical features, computed tomographic findings, and angiographic findings. Patients with causes of embolism (i.e., cardiomyopathy, valvular heart disease, cardiac arrhythmia, and carotid ulceration) were excluded. The 40 patients were classified into three groups according to the site of middle cerebral artery occlusion: there were 13 patients with occlusion of the proximal portion of the M1 segment, 13 with distal M1 segment occlusion, and 14 with occlusion of the M2 segment.

RESULTS

Good collateral circulation was associated with improved outcomes both clinically and by computed tomography in patients with occlusion of the proximal and distal portions of the M1 segment but not in those with M2 occlusion.

CONCLUSIONS

It is reasonable to assume that not only collateral circulation but also the site of occlusion plays an important role in the outcome of middle cerebral artery occlusion. Our finding that good collateral circulation improves the outcome for thrombotic occlusion of the proximal and distal M1 segments supports the possible benefits of such surgery.

[Traumatic carotid-cavernous fistula presenting subarachnoid hemorrhage 5 years after head injury; case report]

A case of traumatic carotid-cavernous fistula (CCF) which presented subarachnoid hemorrhage long after the injury is reported. A 24-year-old male was admitted to the National Yokohama Hospital with complaints of severe headache and nausea. CT scan and cerebral angiography showed subarachnoid hemorrhage due to ruptured CCF. His right visual acuity has disappeared after a traffic accident 5 years before, and he had hit his forehead again 3 years previously. He experienced severe headache twice for 2 weeks after his admission. He was transferred to Kanagawa Rehabilitation Center to be treated with intravascular surgery. Plain CT showed high density areas in the basal cisterns. CT after contrast infusion disclosed a small enlarged high density area in the right cavernous sinus, and showed an enhanced mass lesion in contact with the right ventrolateral side of the midpons. The right internal carotid angiogram showed high flow CCF, fed only by the internal carotid artery. It drained mainly into the basilar plexus, partially into the basal vein of Rosenthal and the inferior petrosal sinus. The CCF was found at the C4 portion of the right internal carotid artery. CT and the angiogram revealed a part of the CCF developing into a varix in the ventral side of the prepontine cistern. It ruptured and the patient developed subarachnoid hemorrhage 5 years after the head injury. The CCF was intravascularly embolized by a detachable balloon. Early treatment for CCF is necessary to prevent the occurrence of subarachnoid hemorrhage if a part of the CCF develops into a varix.

A new intracranial Silastic encircling clip for hemostasis. Technical note

A new encircling clip made of a silicone tube has been designed for treating accidentally injured cerebral vessels. No special holders are necessary. This clip can be tailored depending on the shape of the injured vessel. The clip is a simple and effective tool for achieving complete hemostasis.

[Percutaneous transluminal angioplasty for multiple brachiocephalic artery stenosis: case report]

We encountered a patient with multiple stenotic lesions. He was treated by percutaneous transluminal angioplasty (PTA). The patient, a 59 year-old male, complained of right motor weakness. CT scan showed a multiple low density area (LDA) in the distribution of the right middle cerebral artery (MCA), but did not reveal LDA in the distribution of the left MCA on the affected side. After hospitalization, right motor weakness gradually worsened and aphasia became apparent. A repeat CT scan, 8 days after the stroke, disclosed a new LDA in the left watershed zone and the basal ganglia. Angiographical findings revealed a right ICA occlusion, left ICA stenosis, right VA anaplasia and left subclavian artery stenosis, which proved inadequate for anatomical collateral supply. We treated both the left ICA stenosis and the left subclavian artery stenosis by Dotter balloon dilatation catheter, and successfully obtained sufficient dilatation of the vessels concerned. No complication occurred. PTA is a useful method to use in patients with multiple stenotic lesions which might result in ischemic injury if surgical procedures were used. It would also be of value in cases where surgery using general anesthesia might be highly risky.

Cavernous angioma of the cauda equina producing subarachnoid hemorrhage. Case report

A case of a cavernous angioma of the cauda equina is presented. The patient was a 28-year-old man who experienced sudden low-back pain and headache without neurological symptoms. Lumbar puncture revealed subarachnoid hemorrhage. He had suffered a similar episode 3 years previously. Selective spinal angiography did not demonstrate any abnormal vascularity. Metrizamide myelography and magnetic resonance imaging were useful in demonstrating the presence of a tumor. Laminectomy at L1-3 and total removal of the tumor were performed without neurological deficit.