Moyamoya disease (MMD) is a chronic cerebrovascular occlusive disease of unknown etiology. In addition, the neurocognitive impairment of adults with MMD is infrequently reported and, to date, has not been well described. We attempted to determine both the neurocognitive profile of adult moyamoya disease and whether a superficial temporal artery-middle cerebral artery (STA-MCA) anastomosis can improve the neurocognitive impairment in exhibiting hemodynamic disturbance without stroke.
From September 2010 through November 2012, 12 patients with angiographically diagnosed MMD underwent STA-MCA anastomosis for hemodynamic impairment. Patients with hypoperfusion and impaired cerebrovascular reserve (CVR) capacity but without evidence of ischemic stroke underwent a cognitive function test, the Seoul Neuropsychological Screening Battery (SNSB). Five patients agreed to undergo a follow-up SNSB test. Data from preoperative and postoperative neurocognitive function tests were compared and analyzed.
Five of 12 patients were enrolled. The median age was 45 years (range, 24-55 years). A comparison of preoperative to postoperative status of SNSB, memory domain, especially delayed recall showed significant improvement. Although most of the domains showed improvement after surgery, the results were not statistically significant.
In our preliminary study, large proportions of adult patients with MMD demonstrate disruption of cognitive function. This suggests the possibility of chronic hypoperfusion as a primary cause of the neurocognitive impairment. When preoperative and postoperative status of cognitive function was compared, memory domain showed remarkable improvement. Although further study is needed, neurocognitive impairment may be an indication for earlier intervention with reperfusion procedures that can improve cognitive function.
Neurocognitive impairment; Moyamoya disease; STA-MCA anastomosis
MR perfusion and single photon emission computerized tomography (SPECT) are well known imaging studies to evaluate hemodynamic change between prior to and following superficial temporal artery (STA)-middle cerebral artery (MCA) anastomosis in moyamoya disease. But their side effects and invasiveness make discomfort to patients. We evaluated the ivy sign on MR fluid attenuated inversion recovery (FLAIR) images in adult patients with moyamoya disease and compared it with result of SPECT and MR perfusion images.
We enrolled twelve patients (thirteen cases) who were diagnosed with moyamoya disease and underwent STA-MCA anastomosis at our medical institution during a period ranging from September of 2010 to December of 2012. The presence of the ivy sign on MR FLAIR images was classified as Negative (0), Minimal (1), and Positive (2). Regions were classified into four territories: the anterior cerebral artery (ACA), the anterior MCA, the posterior MCA and the posterior cerebral artery.
Ivy signs on preoperative and postoperative MR FLAIR were improved (8 and 4 in the ACA regions, 13 and 4 in the anterior MCA regions and 19 and 9 in the posterior MCA regions). Like this result, the cerebrovascular reserve (CVR) on SPECT was significantly increased in the sum of CVR in same regions after STA-MCA anastomosis.
After STA-MCA anastomosis, ivy signs were decreased in the cerebral hemisphere. As compared with conventional diagnostic modalities such as SPECT and MR perfusion images, the ivy sign on MR FLAIR is considered as a useful indicator in detecting brain hemodynamic changes between preoperatively and postoperatively in adult moyamoya patients.
Adult moyamoya; Ivy sign; MR FLAIR; STA-MCA anastomosis
This study proposes more objective methods for deciding the appropriate direction of the sylvian fissure dissection during surgical clipping in middle cerebral artery (MCA) bifurcation aneurysms.
We reviewed data of 36 consecutive patients with MCA bifurcation aneurysms. We measured 2 indices preoperatively on 3-dimensional computed tomography angiography (3D-CTA). Analysis of the calculated data allowed us to select the appropriate direction of sylvian fissure dissection for ease of proximal control of M1. Statistically, Mann-Whitney test was used.
We classified subjects into 2 groups based on the technical level of M1 exposure during surgical clipping. When it was difficult to expose M1, subjects were assigned to Group I, and Group II were subjects in whom M1 exposure was easy. The mean difference between the distances extending from the limbus sphenoidale (LS) line to the internal carotid artery bifurcation and extending from the LS line to the MCA bifurcation was 1.00 ± 0.42 mm in group I and 4.39 ± 2.14 mm in group II. The mean M1 angle was 9.36 ± 3.73° in the group I and 34.05 ± 16.71° in the group II (M1 slope gap p < 0.05, M1 angle p < 0.05).
We have found an objective method for preoperatively verifying ease of exposure of M1 artery during surgical clipping. Therefore, we suggest use of the preoperative M1 slope gap and M1 angle as indicators in 3D-CTA selecting the direction of sylvian fissure dissection for easy proximal control of M1.
Middle cerebral artery; Intracranial aneurysm; Dissecting; Three-dimensional cerebral angiography
Removal of the anterior clinoid process (ACP) is an essential process in the surgery of giant or complex aneurysms located near the proximal internal carotid artery or the distal basilar artery. An extradural clinoidectomy must be performed within the limits of the meningeal layers surrounding the ACP to prevent morbid complications. To identify the safest method of extradural exposure of the ACP, anatomical studies were done on cadaver heads.
Anatomical dissections for extradural exposure of the ACP were performed on both sides of seven cadavers. Before dividing the frontotemporal dural fold (FTDF), we measured its length from the superomedial apex attached to the periorbita to the posterolateral apex which connects to the anterosuperior end of the cavernous sinus.
The average length of the FTDF on cadaver dissections was 7 mm on the right side and 7.14 mm on the left side. Cranial nerves were usually exposed when cutting FTDF more than 7 mm of the FTDF.
The most delicate area in an extradural anterior clinoidectomy is the junction of the FTDF and the anterior triangular apex of the cavernous sinus. The FTDF must be cut from the anterior side of the triangle at the periorbital side rather than from the dural side. The length of the FTDF incision must not exceed 7 mm to avoid cranial nerve injury.
Extradural clinoidectomy; Frontotemporal dural fold; Superior orbital fissure; Anatomical study
A dural arteriovenous fistula (DAVF) generally refers to a vascular malformation of the wall of a major venous sinus. These lesions have diverse symptoms according to the location and venous drainage, and require multidisciplinary treatment. We report on our experience and analyze the treatment outcome of intracranial DAVFs for a nine-year period.
Between January 2000 and December 2008, 95 patients with intracranial DAVFs were enrolled in this study. A retrospective review of clinical records and imaging studies of all patients was conducted. Endovascular embolization, surgical interruption, gamma knife stereotactic radiosurgery (GKS), or combinations of these treatments were performed based on clinical symptoms, lesion location, and venous drainage pattern.
Borden type I, II, and III were 34, 48, and 13 patients, respectively. Aggressive presentation was reported in 6% of Borden type I, 31% of Borden type II, and 77% of Borden type III DAVFs, respectively, and DAVFs involving transverse, sigmoid, and superior sagittal sinus. Overall, the rate of complete obliteration was 68%. The complete occlusion rates with a combination treatment of endovascular embolization and surgery, surgery alone, and endovascular embolization were 89%, 86%, and 80%, respectively. When GKS was used with embolization, the obliteration rate was 83%, although it was only 54% in GKS alone. Spontaneous obliteration of the DAVF occurred in three patients. There were a few complications, including hemiparesis (in microsurgery), intracranial hemorrhage (in endovascular embolization), and facial palsy (in GKS).
The hemorrhagic risk of DAVFs is dependent on the location and hemodynamics of the lesions. Strategies for treatment of intracranial DAVFs should be decided according to the characteristic of the DAVFs, based on the location and drainage pattern. GKS can be used as an optional treatment for intracranial DAVFs.
Dural arteriovenous fistula; Signs and symptoms; Therapeutics
Complete removal of three-compartment trigeminal schwannomas is a challenge to neurosurgeons. To expand exposure of each compartment, the combination and modification of skull base approaches are necessary. The 61-year-old woman was admitted with chronic headache. Preoperative magnetic resonance imaging showed 47×50×40 mm-sized tumor originating primarily in the middle cranial fossa extended to the posterior and the infratemporal fossa. We performed operation in five stage; 1. Zygomatic osteotomy, 2. Inferior temporal fossa plate removal and foramen ovale opening, 3. Cavernous sinus opening, 4. Tailored anterior petrosectomy, 5. Meckel's cave opening. Combination of skull base surgery should be concerned according to the patient. In this study, extradural basal extension with zygomatic osteotomy, interdural posterior extension with tailored anterior petrosectomy, and intracavernous exploration are reasonable options for remodeling three-compartment lesion into a single compartment. Tailoring of bone resection and exploring through natural pathway between meningeal layers accomplish single-stage operation for complete removal of tumors.
Multiple compartment; Trigeminal Schwannoma; Technique
Paraclinoid segment internal carotid artery (ICA) aneurysms have historically been a technical challenge for neurovascular surgeons. The development of microsurgical approach, advances in surgical techniques, and endovascular procedures have improved the outcome for paraclinoid aneurysms. However, many authors have reported high complication rates from microsurgical treatments. Therefore, the present study reviews the microsurgical complications of the extradural anterior clinoidectomy for treating paraclinoid aneurysms and investigates the prevention and management of observed complications.
Between January 2004 and April 2008, 22 patients with 24 paraclinoid aneurysms underwent microsurgical direct clipping by a cerebrovascular team at a regional neurosurgical center. Microsurgery was performed via an ipsilateral pterional approach with extradural anterior clinoidectomy. We retrospectively reviewed patients' medical charts, office records, radiographic studies, and operative records.
In our series, the clinical outcomes after an ipsilateral pterional approach with extradural anterior clinoidectomy for paraclinoid aneurysms were excellent or good (Glasgows Outcome Scale : GOS 5 or 4) in 87.5% of cases. The microsurgical complications related directly to the extradural anterior clinoidectomy included transient cranial nerve palsy (6), cerebrospinal fluid leak (1), worsened change in vision (1), unplanned ICA occlusion (1), and epidural hematoma (1). Only one of the complications resulted in permanent morbidity (4.2%), and none resulted in death.
Although surgical complications are still reported to occur more frequently for the treatment of paraclinoid aneurysms, the permanent morbidity and mortality resulting from a extradural anterior clinoidectomy in our series were lower than previously reported. Precise anatomical knowledge combined with several microsurgical tactics can help to achieve good outcomes with minimal complications.
Extradural anterior clinoidectomy; Paraclinoid aneurysm; Clinical outcomes; Surgical complications
Although uncommon, hemorrhage can be a complication of low grade glioma with an unfavorable prognosis such as transformation to higher grade glioma. To our knowledge, hemorrhagic recurrence of World Health Organization Grade II, diffuse astrocytoma without malignant transformation has not been reported. Thus, we report a case of diffuse astrocytoma with hemorrhagic recurrence without malignant transformation. The patient had undergone craniotomy and tumor removal 7 years previously. Annual follow-up MRIs had shown evidence of slow tumor recurrence. With the sudden onset of seizure, the patient was diagnosed as hemorrhagic recurrence and underwent second tumor removal highly suspecting malignant change into higher grade glioma. Histopathology confirmed diffuse astrocytoma without malignant changes. As the patient's postoperative condition was excellent, we plan to withhold chemotherapy and radiation therapy for use as a later treatment option.
Astrocytoma; Glioma; Recurrence
Treatment of complex aneurysms usually entails not only direct clipping but also alternative treatment modality. We recently experienced a case of vertebral artery dissecting aneurysm and obtained good treatment outcomes. Our case suggests that the endovascular segmental occlusion with posterior inferior cerebellar artery (PICA) to PICA side anastomosis might be a good treatment option in patients with complex vertebral artery dissecting aneurysms. A 45-year-old woman has a left vertebral dissecting aneurysm with dizziness. Based on the aneurysmal morphology and the involvement of PICA, the patient underwent side to side anastomosis of the PICA. This was followed by the endovascular segmental coil occlusion. The aneurysmal sac was completely obliterated. At a 2-year follow-up, the patient achieved a good patency of both PICA. In conclusion our case suggests that the endovascular segmental occlusion of the parent artery followed by PICA to PICA bypass surgery through a midline suboccipital approach is a reasonable multimodal treatment option in patients with complex vertebral artery dissecting aneurysms.
PICA dissecting aneurysm; Segmental occlusion; Multimodal treatment; Complex aneurysm
The best treatment for clival chordoma is obtained with total surgical excision, sometimes combined with adjuvant radiotherapy. A cerebrospinal fluid (CSF) fistula is a fatal complication that may occur following extended transsphenoidal surgery (TSS) and adjuvant radiotherapy. We report a case of fulminant meningitis without a CSF fistula in a 57-year-old woman who underwent TSS and multiple radiotherapies for a clival chordoma. She presented to our emergency room with copious epistaxis and odor inside her nasal cavity and had an unexpected fatal outcome. She was diagnosed with meningitis based on CSF culture and blood culture. While treating clival chordomas with adjuvant radiotherapy, clinicians should be aware of the possibility of fulminant meningitis.
Chordoma; Radiotherapy; Meningitis
The purpose of this study is to analyze clinical characteristics and surgical outcomes of the far lateral and the paramedian disc herniations.
The 88 patients who underwent an operation for lumbar disc herniations were reviewed. Visual analogue scale of leg and back pain, occurrence of sensory dysesthesia and motor deficit before and after operations were used to compare the far lateral with the paramedian disc herniations.
Statistically, the far lateral herniations had more severe radicular leg pain and showed more frequent occurrence of sensory dysesthesia than paramedian herniations before operation (p<0.05). In the far lateral herniation group, preoperatively, 15 patients (75%) had sensory dysesthesia and among them, 4 patients (27%) showed improvement. In the paramedian herniation group, preoperatively, 25 patients (37%) had sensory dysesthesia and among them, 21 patients (84%) showed improvement. The degree of improvement in sensory dysesthesia was statistically higher in paramedian herniation group (p<0.05). In the far lateral herniation group, preoperatively, 11 patients (55%) had motor deficit and among them, 10 patients (91%) showed improvement. In the paramedian herniations, preoperatively, 29 patients (43%) had motor deficit and among them, 25 patients (86%) showed improvement. The degree of improvement in motor deficit was not statistically significant between groups (p>0.05).
Preoperatively, the far lateral herniations had more severe radicular leg pain and frequent occurrence of sensory dysesthesia. Postoperatively, the sensory dysesthesia was less improved and back pain was more severe in the far lateral herniations.
Far lateral disc herniation; Paramedian disc herniation; Clinical characteristics; Surgical outcomes
Ankylosing spondylitis (AS) is a chronic systemic and inflammatory rheumatic disease with a variable course of the axial skeleton. Spinal involvement may accompany ossification of the ligaments, intervertebral disc, end-plates and apophyseal structures, and seems to be "bamboo spine". Because of these natures of the spine in AS, a spinal fracture can be occurred with minor trauma or spontaneously. The fracture of the AS can cause neurological complications extremely high, so special attention to prevent neurological deterioration. Operative management of the injured spine with AS is difficult, and associated with a high complication rate. Extreme care must be taken for surgery to prevent secondary neurological deterioration.
Ankylosing spondylitis; Lumbar fracture; Postoperative complication; Neurological deterioration
Epidermoid tumor of the cavernous sinus is rare. The aim of this case report is to discuss the role of neuroendoscopes in the removal of such lesions. A 21-year-old man presented with 6-year history of progressive headache, diplopia, and visual disturbance. Work-up revealed an epidermoid tumor located in the right cavernous sinus. An extradural transcavernous approach was utilized via a traditional frontotemporal craniotomy with endoscopic assistance. The postoperative course was uneventful with immediate improvement of the patient's headache. Postoperative magnetic resonance imaging demonstrated complete removal of the tumor. There were no signs of recurrence during a 2-year follow-up period. The endoscope is a useful tool for removing epidermoid tumors from the cavernous sinus and enhances visualization of areas that would otherwise be difficult to visualize with microscopes alone. Endoscopes also help minimize the retraction of neurovascular structures.
Epidermoid tumor; cavernous sinus; endoscope-assisted microsurgery
Recurrent lumbar disc herniation has been defined as disc herniation at the same level, regardless of ipsilateral or contralateral herniation, with a pain-free interval greater than 6 months. The aim of this study is to analyze outcomes and identify the potential risk factors for recurrent lumbar disc herniation.
The authors retrospectively reviewed the cases of 178 patients who underwent open discectomy for single-level lumbar disc herniation. Visual analogue scales and modified Macnab criteria were used to compare the clinical outcomes between the recurrent group and the non-recurrent group.
Sex, age, discectomy level, degree of disc degeneration, type of disc herniation, pain-free interval after first-operation, smoking status, and trauma were investigated as potential recurrence risk factors.
Of the 178 patients for whom the authors were able to definitely assess symptomatic recurrence status, 18 patients (10.1%) underwent revision surgery for recurrent disc herniation. The most common level involved was L4-L5 (61%) and the mean period of time to recurrence was 18.7 months (6-61 months). There were 17 cases of ipsilateral herniation and 1 case of contralateral herniation. The types of herniation for which revision surgery was done were protrusion (3 cases), and transligamentous extrusion (14 cases). There were five excellent, eight good, and two fair results.
Repeated discectomy for recurrent disc herniation produced unsatisfactory outcomes. Factors such as sex, type of disc herniation and traumatic events were found to be significant risk factors.
Lumbar vertebrae; Discectomy; Recurrence; Risk factors
Spontaneous cervical epidural hematoma (SCEH) is a rare clinical entity and has a varied etiology. Urgent surgical decompression should be done to prevent serious permanent neurologic deficits. We describe a 59-year-old female who presented with Brown-Sequard syndrome due to spontaneous cervical epidural hematoma. Initially, she was misdiagnosed as cerebrovascular accident. Cervical magnetic resonance imaging revealed epidural hematoma to the right of the spinal cord extending from C3 to C6. She later underwent surgical evacuation and had complete restoration of neurologic function. The outcome in SCEH is essentially determined by the time taken from onset of the symptom to operation. Therefore, early and precise diagnosis such as careful history taking and MRI evaluation is mandatory.
Spontaneous cervical epidural hematoma; Brown-Sequard syndrome; Surgical decompression
While many factors contribute to aging, changes in calcium homeostasis and calcium related neuronal processes are likely to be important. High intracellular calcium is toxic to cells and alterations in calcium homeostasis are associated with changes in calcium-binding proteins, which confine free Ca2+. We therefore assayed the expression of the calcium binding proteins calretinin and calbindin in the central auditory nervous system of rats.
Using antibodies to calretinin and calbindin, we assayed their expression in the cochlear nucleus, superior olivary nucleus, inferior colliculus, medial geniculate body and auditory cortex of young (4 months old) and aged (24 months old) rats.
Calretinin and calbindin staining intensity in neurons of the cochlear nucleus was significantly higher in aged than in young rats (p<0.05) The number and staining intensity of calretinin-positive neurons in the inferior colliculus, and of calbindin-positive neurons in the superior olivary nucleus were greater in aged than in young rats (p<0.05).
These results suggest that auditory processing is altered during aging, which may be due to increased intracellular Ca2+ concentration, consequently leading to increased immunoreactivity toward calcium-binding proteins.
Calcium-binding proteins; Aging; Auditory pathway