Adverse effects of intravenous acetazolamide administration for evaluation of cerebrovascular reactivity using brain perfusion single-photon emission computed tomography (SPECT) were prospectively investigated in 100 patients with major cerebral artery, atherosclerotic, and steno-occlusive diseases. All patients underwent two SPECT studies (with and without acetazolamide challenge) at an interval of 2 or 3 days, received a questionnaire immediately after each SPECT study, and returned the answered questionnaire within 7 days after the study. None of the 100 patients studied experienced any symptoms during the SPECT study without acetazolamide challenge. Sixty-three patients (63%) developed symptoms during the SPECT study with acetazolamide challenge, such as headache, nausea, dizziness, tinnitus, numbness of the extremities, motor weakness of the extremities, and general malaise 1-3 hours (mean 1.6 hours) after administration of acetazolamide, and these symptoms lasted for 0.5-72 hours (mean 7.9 hours). Multivariate statistical analysis revealed that younger age (95% confidence interval [CI] 0.896-0.980, p = 0.0047) and female sex (95% CI 1.178-16.129, p = 0.0274) were significantly associated with development of symptoms with acetazolamide challenge. The incidences of the development of symptoms with acetazolamide challenge were 91% (21/23) and 41% (12/29) in subgroups of women <70 years and men ≥70 years, respectively. Patients should be informed of such adverse effects of intravenous acetazolamide administration prior to the acetazolamide challenge test for evaluation of cerebrovascular reactivity.
The clinical features of radiculopathy caused by osteoporotic vertebral fractures (OVFs) in the lumbar spine were investigated in 66 patients treated for pain caused by OVFs from January 2006 to December 2009. Ten of the patients complained of persistent radiculopathy. The cause of radiculopathy was initially diagnosed as lumbar canal stenosis (LCS) in seven patients, lumbar foraminal stenosis (LFS) in two, and both in one. One patient with LFS had reduced pain with conservative treatment, and the other nine needed surgical treatments. LCS was treated with posterior decompression, and LFS complicated with LCS at the same spinal level was treated with posterior lumbar interbody fusion (PLIF). Vertebroplasty was performed for one patient with LFS to attain indirect nerve root decompression achieved as a result of vertebral reconstruction and stabilization. Four of the patients treated with posterior decompression for LCS suffered from residual radiculopathy postoperatively, which was caused by LFS at the same level or the level below the treated level. Two patients underwent second operative procedure (PLIF) for recurrent radiculopathy. The Japanese Orthopedic Association and Visual Analogue Scale scores of the pain improved after operations, but the scores of the patients treated without spinal fusion gradually worsened during the follow-up period, whereas the scores of the patients treated with PLIF remained stable at various levels. Seven of the ten patients developed LFS following OVF, suggesting that radiculopathy following OVF involves LFS with high frequency.
We have routinely used an intraoperative CT (i-CT) system in over 800 neurosurgical procedures since 1997. To investigate the utility of i-CT in low-grade glioma (LGG) surgery, we investigated whether i-CT improved the extent of tumor resection and prognosis in 46 patients with histologically confirmed LGG consisting of 27 patients with World Health Organization grade II astrocytoma, 12 with oligodendroglioma, and 7 with oligoastrocytoma. The patients were divided into two groups, 23 who underwent tumor resection without i-CT (non i-CT group) and 23 who underwent surgery using i-CT (i-CT group). We investigated the extent of tumor resection, pre- and postoperative Karnofsky performance status scores, and overall survival in each group. The extent of tumor resection was biopsy 26.1%, partial resection 60.9%, subtotal resection 13.0%, and gross total resection 0% in the non i-CT group, and 4.4%, 21.7%, 34.8%, and 39.1%, respectively, in the i-CT group. The i-CT group showed significantly longer overall survival than the non i-CT group among patients with astrocytoma (p < 0.05) and oligodendroglioma or oligoastrocytoma (p < 0.005). Prolonged survival was related to the extent of resection. There were no significant differences between pre- and postoperative Karnofsky performance status scores between the groups. Surgical resection using i-CT may improve the outcomes of patients with LGG. Additional resection or emergency treatment can be quickly performed as the surgical results are confirmed intraoperatively or immediately after the operation using i-CT.
Motor cortex stimulation (MCS) is a treatment option for various disorders such as medically refractory pain, poststroke hemiplegia, and movement disorders. However, the exact mechanisms underlying its effects remain unknown. In this study, the effects of long-term chronic MCS were investigated by observing changes in astrocytes. A quadripolar stimulation electrode was implanted on the dura over the sensorimotor cortex of adult rats, and the cortex was continuously stimulated for 3 hours, 1 week, 4 weeks, and 8 weeks. Immunohistochemical staining of microglia (ionized calcium-binding adaptor molecule 1 [Iba1] staining) and astrocytes (glial fibrillary acidic protein [GFAP] staining), and neuronal degeneration histochemistry (Fluoro-Jade B staining) were carried out to investigate the morphological changes following long-term chronic MCS. Iba1 staining and Fluoro-Jade B staining showed no evidence of Iba1-positive microglial changes or neurodegeneration. Following continuous MCS, GFAP-positive astrocytes were enlarged and their number increased in the cortex and the thalamus of the stimulated hemisphere. These findings indicate that chronic electrical stimulation can continuously activate astrocytes and result in morphological and quantitative changes. These changes may be involved in the mechanisms underlying the neuroplasticity effect induced by MCS.
A 62-year-old man presented with dissection of the right middle cerebral artery (MCA) manifesting as mild headache, right hemiparesis, and slurred speech. Magnetic resonance (MR) imaging and MR angiography revealed fresh infarction in the right basal ganglia, and severe stenosis and dilatation of the right MCA. Digital subtraction angiography approximately 24 hours after admission revealed a linear contrast defect indicating an intimal flap of the M1 segment. The diagnosis was dissection of the MCA. His neurological deficits improved gradually. Although he was neurologically stable, diffusion-weighted MR imaging revealed enlarging infarct size over the right MCA territory, and the right M1 segment had progressive stenosis. Superficial temporal artery (STA)-MCA anastomosis was performed on the 26th day. Follow-up angiography showed good patency of the STA-MCA anastomosis, repair of the dissection of the M1 segment, and improvement of the flow in the MCA. The patient was discharged from our hospital with no neurological deficits. Although the dissection in this case was spontaneously repaired, STA-MCA anastomosis was useful to get through a critical time. If the stenosis shows further progression or the infarction size enlarges, STA-MCA anastomosis may be effective.
A 60-year-old female presented with a carotid-cavernous fistula (CCF) manifesting as left abducens nerve palsy. Left internal carotid digital subtraction angiography showed a persistent primitive trigeminal artery (PPTA) near the CCF. Super-selective angiography showed direct shunt flow between the PPTA trunk aneurysm and the left cavernous sinus. The aneurysm was successfully occluded with detachable coils. The CCF disappeared and the PPTA was preserved. The abducens nerve paralysis had disappeared 6 months later. CCF caused by a PPTA trunk aneurysm is extremely rare. We speculate that the PPTA trunk aneurysm formed and then ruptured due to hemodynamic stress caused by hypoplasia of the basilar artery.
A 44-year-old female presented with left occipital arteriovenous malformation (AVM) manifesting as sudden onset of severe headache. Magnetic resonance (MR) imaging and conventional angiography showed the left occipital AVM with hemorrhage. Intraoperative MR imaging (iMR imaging) and intraoperative time-resolved imaging of contrast-kinetics (iTRICKS) at 1.5 T revealed complete removal of the nidus of the AVM without conventional catheter angiography. Conventional catheter angiography is commonly used in preoperative and intraoperative examination of AVMs, and for documentation of the surgical outcome, but less-invasive techniques are desirable for both preoperative screening and intraoperative examination. iMR imaging with iTRICKS is less invasive and safer than conventional angiography for both brain tumor surgery and AVM surgery.
A 78-year-old Japanese man with a history of colon cancer was referred to our department of neurosurgery for the management of asymptomatic left chronic subdural hematoma (CSDH). He was receiving bevacizumab therapy for colon cancer, and the size of the CSDH increased or decreased depending on bevacizumab administration. Simple drainage was performed because of the risk of a critical increase in the size of CSDH during bevacizumab therapy, but since the CSDH was organized and firm, the drainage was insufficient. Therefore, neuroendoscope-assisted craniotomy was performed, and the organized CSDH was almost completely removed. The present case indicates the possible involvement of bevacizumab in the occurrence of CSDH and the efficacy of the neuroendoscopic approach in the surgical treatment of organized CSDH.
A 28-year-old man presented with a case of spontaneous intracranial hypotension (SIH) manifesting as a bilateral chronic subdural hematoma (CSDH) without orthostatic headache. He developed life-threatening acute SDH as a complication of CSDH drainage. Neurosurgeons should be aware that SIH patients do not always present with orthostatic headache. Brain magnetic resonance imaging with gadolinium may be recommended for young adults with non-traumatic CSDH before drainage to exclude SIH, even if they do not present with orthostatic headache.
A 26-year-old man presented with a case of angiocentric glioma manifesting as medically refractory epilepsy. Magnetic resonance imaging revealed a hyperintense lesion in the right superior frontal gyrus on T2-weighted imaging, with cortical hyperintense rim on T1-weighted images and minimum contrast enhancement. Video-electroencephalography (EEG) monitoring characterized his seizures as originating from the right frontal lobe. Long-term EEG recording from implanted subdural electrodes disclosed epileptic activities extending beyond the margin of the radiological lesion. Extended cortical resection of the superior frontal gyrus including the tumor and the surrounding epileptic cortices was performed. Postoperatively, he became seizure-free with antiepileptic medication during a 12-month follow-up period. Histological examination of the surgical specimen showed the characteristic findings of angiocentric glioma. Associated cortical dyslamination consistent with cortical dysplasia was found in the surrounding cortex. Angiocentric glioma is a slow-growing or stable tumor frequently presenting with intractable epilepsy. Surgical treatment would be aimed primarily at control of epilepsy. Complete lesionectomy usually results in postoperative seizure freedom, but the present case shows evidence for associated cortical dysplasia with this tumor entity. Careful pre-surgical evaluation for epilepsy is necessary to achieve better seizure outcome.
A 55-year-old woman presented with an extremely rare primary central nervous system mucosa-associated lymphoid tissue (MALT) lymphoma manifesting as seizure and was subsequently diagnosed with dural MALT lymphoma in the cranium. Magnetic resonance imaging revealed a left frontal dural mass with peritumoral edema. Histological examination of the dural mass confirmed MALT lymphoma and revealed infiltration of small cells with irregular nuclear borders and expression of a B cell marker (CD20) but absence of CD5, CD10, CD23, and cyclinD1. Reactive T-cell infiltration was also seen. Subsequently, local irradiation (40 Gy/20 fractions) was performed. Magnetic resonance imaging showed complete remission just after irradiation was completed. There was no evidence of systemic MALT lymphoma. There has been no recurrence for 3 years without additional therapy.
Two cases of endodermal cyst of the posterior fossa are reported. A 12-year-old girl presented with severe headache and vomiting caused by increased intracranial pressure. Computed tomography and magnetic resonance (MR) imaging showed a cystic mass occupying the ambient and quadrigeminal cisterns. A 65-year-old woman presented with dizziness, and MR imaging revealed a cystic mass in the posterior fossa. The two patients underwent surgery for decompression and resection of the cyst. Surgical specimens of the cyst walls consisted of a single layer of ciliated columnar epithelium. The diagnoses were endodermal cyst. The optimal surgical goal is total resection of the cyst wall, but the cyst wall sometimes tightly adheres to the adjacent nerves, vessels, and vital structures. The cyst must communicate adequately with the surrounding cerebrospinal fluid space, and a newly closed cyst space must be avoided, by the widest possible resection of the cyst wall.
A 34-year-old male presented with a rare case of Rathke's cleft cyst (RCC) with calcification manifesting as persistent high fever and impaired consciousness. Physical findings revealed panhypopituitarism and bitemporal hemianopsia. Computed tomography showed mass lesions with marked calcification within the sella turcica and the suprasellar region. Magnetic resonance imaging showed solid and cystic components compressing the optic nerve. The preoperative diagnosis was craniopharyngioma. Initial endonasal transsphenoidal surgery (TSS) was performed with a surgical microscope, but the mass was extremely hard, so only partial removal was possible. Second endonasal extended TSS was performed with a neuroendoscope. The solid components were totally removed, but calcifications adhering to the optic nerve could not be removed completely. The histological diagnosis was RCC with marked granulation reaction. RCC with calcification is rare and difficult to differentiate from craniopharyngioma on neuroimages. Extremely thick calcification of the sella turcica enclosing granulation tissue and the cyst similar to armor, here called “armor-like calcification,” is a characteristic imaging finding of RCC with calcification. The most important aspect is choosing a surgical approach to carefully and effectively relieve pressure upon the optic nerve. Endonasal extended TSS with an endoscope was effective in the present case.
A 69-year-old male presented with a rare spinal angiolipoma manifesting as history of back pain, and numbness in both lower limbs, which progressed over a period of 5 years. Total T10-T12 laminectomy was performed and the tumor was removed en bloc. The symptoms gradually improved postoperatively. Spinal angiolipoma is an uncommon benign extradural tumor of spine, which accounts for 0.14-1.2% of all spinal tumors and is a rare cause of spinal cord compression. Recognition of this entity is crucial as a benign and curable cause of paraplegia and back pain.
We designed a new endoscopic surgical procedure for putaminal hemorrhage (freehand technique) and evaluated its effectiveness and safety in patients with putaminal hemorrhage. Computed tomography (CT) data sets from 40 healthy patients were used. The CT data were transformed into three-dimensional images using AZE VirtualPlaceTM Plus. The nasion and external auditory foramen were the intraoperative reference points. The median point from medial of the globus pallidus to the insula was the target point. The location of the burr hole point was 80-125 mm above and 27.5 mm lateral to the nasion, and the direction was parallel to the midline and a line drawn from the burr hole to the ipsilateral external auditory foramen. This point was used for 15 patients with putaminal hemorrhage. In all cases, only one puncture was required, and there were no complications. The median surgical time was 91.7 minutes, and the median hematoma removal rate was 95.9%. No recurrent bleeding or operative complications occurred. The freehand technique is a simple and safe technique for patients with putaminal hemorrhage. We believe that this technique of endoscopic hematoma evacuation may provide a less-invasive method for treating patients with putaminal hemorrhage.