Anatomical Consideration of the Anterior and Lateral Cutaneous Nerves in the Scalp

To better understand the anatomic location of scalp nerves involved in various neurosurgical procedures, including awake surgery and neuropathic pain control, a total of 30 anterolateral scalp cutaneous nerves were examined in Korean adult cadavers. The dissection was performed from the distal to the proximal aspects of the nerve. Considering the external bony landmarks, each reference point was defined for all measurements. The supraorbital nerve arose from the supraorbital notch or supraorbital foramen 29 mm lateral to the midline (range, 25-33 mm) and 5 mm below the supraorbital upper margin (range, 4-6 mm). The supratrochlear nerve exited from the orbital rim 16 mm lateral to the midline (range, 12-21 mm) and 7 mm below the supraorbital upper margin (range, 6-9 mm). The zygomaticotemporal nerve pierced the deep temporalis fascia 10 mm posterior to the frontozygomatic suture (range, 7-13 mm) and 22 mm above the upper margin of the zygomatic arch (range, 15-27 mm). In addition, three types of zygomaticotemporal nerve branches were found. Considering the superficial temporal artery, the auriculotemporal nerve was mostly located superficial or posterior to the artery (80%). There were no significant differences between the right and left sides or based on gender (P>0.05). These data can be applied to many neurosurgical diagnostic or therapeutic procedures related to anterolateral scalp cutaneous nerve.

Rapid Progression of Early Delayed Radiation Effect in Pleomorphic Xanthoastrocytoma

Early delayed radiation effects are known to occur within several months after completing radiotherapy for brain tumors. We present marked changes of magnetic resonance imaging (MRI) scan that occurred one month after radiotherapy in a patient with a pleomorphic xanthoastrocytoma, which was eventually diagnosed as an early delayed radiation effect. Such an early development of dramatic MRI change has not been reported in patients treated with radiotherapy for pleomorphic xanthoastrocytomas.

Clinical Analysis of Spontaneous Subarachnoid Hemorrhage with Negative Angiography / 대한뇌혈관외과학회지

OBJECTIVE: Most cases of spontaneous subarachnoid haemorrhage (SAH) are due to a ruptured cerebral aneurysm, yet sometimes the cause of bleeding can be obscure. We report here on the results of a retrospective single-center study to determine the role of the hemorrhage patterns for the patients with a negative angiogram on admission. METHODS : A total of 480 patients with spontaneous subarachnoid hemorrhage (SAH) were admitted from January 2004 to September 2008. Of these, 44 patients were included in this study because of their negative findings on their initial angiography. SAH was diagnosed by a computed tomographic scan or lumbar puncture. The clinical grade was assessed using the Hunt-Hess grading system, Fisher's grading system and the modified Rankin scale. RESULT : The overall incidence of an initially negative angiogram for patients with a spontaneous SAH was 10.2%. Based on the hemorrhage pattern on the admission CT, the most common pattern was the diffuse type (52.3%), followed by the perimesencephalic type (29.5%), the CT negative type (11.4%) and the localized non-perimesencephalic type (6.8%). The repeat angiogram revealed an aneurysm in 3 (7.7%) patients and exploration revealed a dissecting aneruysm of the vertebral artery in 1 patient. The patients with the diffuse type SAH significantly differed from the perimesencephalic group with regard to the Fisher grade (p = 0.002), the outcome at discharge (p = 0.004) and the need for EVD. CONCLUSION : Patients with SAH of an unknown cause, especially with perimesencephalic SAH, have an excellent prognosis and low mortality. We believe that digital subtraction angiogram is still the gold standard for making the diagnosis of aneurysm in patients with spontaneous SAH. A repeat angiogram is recommended for all the patients with initially angionegative SAH. For those patients with perimesencephalic SAH and a positive CSF study with a negative CT, we suggest to perform a CT angiogram as a less invasive follow-up study.

Surgical Management of Acute Cerebellar Infarction

OBJECTIVE: The aim of this study is to determine which patients with progressively deteriorating acute cerebellar infarction would benefit from surgical treatment and which surgical procedure would best benefit them. METHODS: Seventy six patients were treated at our hospital for cerebellar infarction over the past 3 years. Sixty nine patients received conservative management in the neurological department of our hospital. Among them, 7 patients (5 males and 2 females; average age, 49 yrs) were referred to neurosurgical department because of mental deterioration and underwent emergency surgery. Five patients underwent external ventricular drainage with suboccipital craniectomy and two patients underwent suboccipital craniectomy alone. RESULTS: Of the 7 surgically treated patients, 4 patients experienced good recovery and 2 patients experienced moderate disability (disabled but independent) and 1 patient experienced severe disability (conscious but disabled). There was no death. CONCLUSION: In patients conservatively treated for cerebellar infarction and showing mental deterioration and radiologically evident brainstem compression and ventricular enlargement, we strongly recommend suboccipital craniectomy (plus optional external ventricular drainage in case of showing hydrocephalus) as a first treatment option.

Hyperacute Radiation Effect on Cerebral Cortex after Local Gamma-irradiation in the Rat Brain

OBJECTIVE: We investigated the morphologic changes within 24 hours after a single gamma-irradiation in the rat brain. METHODS: Forty Sprague-Dawley rats were used. After a burr hole trephination on right parietal area, cerebral hemisphere was irradiated with 2Gy and 5Gy using iridium-192(192Ir), respectively. The effect was assessed at 4, 8, 12 and 24 hours after irradiation. The histological changes were scored following the detection of edema or disarray severity. TUNEL-positive cells exhibiting apoptotic morphology were counted in irradiated region. RESULTS: Cortical edema and disarray were initially showed at 4 or 8hour and almost all defined at 24hour after irradiation. And the injury was wedge shape. TUNEL-positive cells were minimal at 8hour after irradiation as the number of positive cells were 2.6+/-5.27(n=5) after 2Gy, and 0.8+/-0.84(n=5) after 5Gy. But, the number of apoptotic cells were increased markedly to 60+/-6.24 at 12hour after 2Gy and to 104+/-19.7 at 24hour after 5Gy. CONCLUSION: There were prominent morphologic changes immediately after gamma-irradiation. And, apoptosis was increased according to the time period. These findings implicate that brain irradiation induces rapid apoptotic change, which may play an important role in the pathogenesis of radiation-induced pathologic conditions.

Cranioplasty with the Porous Polyethylene Implant(Medpor) for Large Cranial Defect

OBJECTIVE: This paper describes our experience and implant technique for cranioplasty of a large cranial defects using a porous polyethylene implant(Medpor) and compares the results with polymethylmethacrylate(PMMA). METHODS: Sixteen cranioplasties were performed using Medpor(n=10) and PMMA(n=6) implants between June 2003 and January 2005. The criterion for patient enrollment was a defect larger than 10cm in diameter. This study compared the operation times and complications. RESULTS: The operation times ranged from 105 to 250minutes(Mean 180 degrees +/-44minutes) in Medpor and from 185 to 460minutes (mean 128minutes) in PMMA. The absolute operation times were shorter using the Medpor implant and the differences were statistically significant(P=0.030). Satisfactory cosmetic results were obtained in all cases using the Medpor implant and with no implant-related complications. Bone ingrowth to the medpor implant was presumed to be the result on an increase in Houndsfield units of the implant, particularly at the marginal areas in the serial follow-up brain computed tomography images. CONCLUSION: It is believed that the properties of a Medpor implant make this implant an good alternative to the existing methods of a cranial contour correction. However, a further follow-up study will be needed.

Upregulation of VEGF and FGF2 in Normal Rat Brain after Experimental Intraoperative Radiation Therapy

The expression of vascular endothelial growth factor (VEGF) and fibroblast growth factor (FGF)2 in the irradiated brain was examined to test how a single high dose radiation, similar to that used for intraoperative radiation therapy given to the normal cerebrum, can affect the vascular endothelium. After a burr hole trephination in the rat skull, the cerebral hemisphere was exposed to a single 10 Gy dose of gamma rays, and the radiation effect was assessed at 1, 2, 4, 6, and 8 weeks after irradiation. His-tological changes, such as reactive gliosis, inflammation, vascular proliferation and necrosis, were correlated with the duration after irradiation. Significant VEGF and FGF2 expression in the 2- and 8-week were detected by enzyme-linked immunosorbent assay quantification in the radiation group. Immunohistochemical study for VEGF was done and the number of positive cells gradually increased over time, compared with the sham operation group. In conclusion, the radiation injuries consisted of radiation necrosis associated with the expression of VEGF and FGF2. These findings indicate that VEGF and FGF2 may play a role in the radiation injuries after intraoperative single high-dose irradiation.

Posterior Leukoencephalopathy Syndrome Following Intravenous Chemotherapy for Medulloblastoma in a Child

Posterior leukoencephalopathy syndrome(PLES) is a rare neurological complication which is associated with malignant hypertension, pre-eclampsia, and some drugs including immunosuppressive agents. A 9-year-old boy who had cerebellar medulloblastoma showed seizure on the seventeenth day after intravenous chemotherapy including ACNU and vincristine. Radiologic findings were consistent with those of PLES due to vasospasm. After hypertensive therapy, the symptoms were improved. We present a case of PLES with medulloblastoma which developed following chemotherapy with the regimen of medulloblastoma in a child.

Preliminary Clinical Experience of Anterior Cervical Interbody Fusion with the AMSLU(TM) Cage

OBJECTIVE: The authors investigate the effectiveness and the demerits of the AMSLU(TM) cervical cage used in cervical spinal fusion for correction of cervical degenerative disc disease. METHODS: A total of 19 patients with cervical degenerative disc disease underwent anterior microdiscectomy and the AMSLU(TM) cage fusion. We made a retrospective comparative analysis between cases using the AMSLU(TM) cage and the classical autogenous iliac crest graft(AICG) with plate fixation about operative time, blood loss and hospital stay. The patient's neurological and functional outcomes were assessed on the basis of the modified Odom's criteria. RESULTS: The use of the AMSLU(TM) cage was found to save operative time(mean, 153+/-52min: P=0.004) and blood loss(mean, 236+/-171cc: P=0.032) as compared with the use of AICG. There was no donor-site complications and all patients were tolerable to ambulation at 1 day postoperatively. The patient's clinical success rate was 89% on discharge and 84% at 6 months postoperatively. CONCLUSION: The use of the AMSLU(TM) cage provides several advantages: no donor-site complications, brief instrument procedures, short operative time, small amount of blood loss and satisfactory clinical success rate. But it also has many limitations: short follow up period, kyphotic change and subsidence. Further investigations and clinical applications are necessary to use AMSLU(TM) cage in cases of spondylolisthesis and traumatic cervical disease.

Multiple Infarcts after Intra-arterial Carboplatin Therapy

We report a case of multiple cerebral infarcts, which developed after intra-arterial(IA) carboplatin therapy in a patient with glioblastoma who had received surgery with conventional and intraoperative radiation therapy (IORT). A 31-year-old male patient presented with one-month history of worsening headaches and visual dimness. Seven years previously, he had been subjected to a subtotal resection of anaplastic astrocytoma in the right occipital lobe, followed by external radiation therapy with a total dose of 5580cGy. Carboplatin was given at an initial dose of 300mg/m2. Before and after the infusion of carboplatin, solumedrol(500mg/day) was given for seven days, with the dosage being gradually reduced over the next five days. In addition, 20% mannitol(100ml) was infused over a 15-minute period before chemotherapy, and the fluid volume of electrolyte was adjusted to maintain an optimal urine output. The patient underwent five cycles of IA carboplatin therapy. Careful attention should be given during IA carboplatin chemotherapy to patients who are also being treated with IORT.

Idiopathic Granulomatous Hypophysitis

Idiopathic granulomatous hypophysitis is a chronic inflammation of the pituitary gland. It has a rare occurrence and is diagnosed only on pathologic examination. We report a case of a 60-year-old patient presenting with headache, vomiting and isolated hyponatremia. MRI study showed a space occupying lesion of the pituitary gland with a marked enhancement after gadolinium injection. Pituitary biopsy was consistent with the diagnosis of idiopathic granulomatous hypophysitis. The aim of this case report is to discuss the variable clinical and radiological aspect of the disease.

Evaluation of Cerebrospinal Fluid Vascular Endothelial Growth Factor for the Brain Tumor

OBJECTIVE: Vascular endothelial growth factor(VEGF), which is also known as vascular permeability factor, induces angiogenesis and may play a key role in tumor-related neovascularization and peritumoral edema. There are many pathological conditions associated with VEGF expression, such as brain tumor, infection and trauma. Malignant brain tumor is characterized by its prominent neovascularization and severe peritumoral edema and it is known to express high VEGF activity. The aim of this study is to investigate any differences in cerebrospinal fluid(CSF) VEGF level among gliomas, and between tumors and non-tumorous conditions. METHODS: Cerebrospinal fluid samples were collected from 28 patients whose diagnosis had been surgically proven and they were centrifuged and stored at -73 degrees C. The concentration of VEGF was analyzed using commercially available ELISA kit. RESULTS: Glioblastoma patients showed much higher level of CSF VEGF than those of other gliomas and non-tumorous conditions. And higher CSF VEGF level was found in invasive pituitary adenoma, recurrent oligoden-droglioma, central neurocytoma and diffuse axonal injury. CONCLUSION: Absolute CSF VEGF level can be useful biological marker for primary malignant glioma, especially glioblastoma, and serial check-ups may contribute to early diagnosis of malignant transformation of low grade astrocytoma.

Cavernous Malformation after Radiation Therapy for Pilocytic Astrocytoma: Case Report

We report a case of de novo development of cavernous malformation after cranial irradiation. The patient was a 19-year-old male who had been operated on 10 years ago for cerebellar pilocytic astrocytoma. After subtotal tumor removal, he had received cranial irradiation for the residual tumor. He was readmitted for extraocular muscle palsy, dysarthria and facial weakness about 10 years after operation and irradiation. Magnetic resonance imaging of the brain showed an abnormal mixed signal lesion in the lower pons and pontomedullary junction. The patient underwent surgical removal of the hematoma in the pons and the cavernous malformation was identified.

Giant Cystic Craniopharyngioma Extended into the Posterior Fossa down to the Medulla Oblongata: Case Report

Cystic retrochiasmatic craniopharyngioma may reach enormous size by expanding into the posterior fossa along the retroclival area, which is very unusual finding. An 11-year-old girl presented with walking disturbance and irritability. On the neurological examination, she had positive Babinski sign, hyperactive deep tendon reflex, and left lateral gaze nystagmus. She also had right hearing disturbance. Initial magnetic resonance(MR) images revealed a huge, thin capsuled cystic mass which extended into the cerebellopontine angle down to the medulla oblongata. Secondary adjuvant chemotherapy, radiotherapy, and reoperation were necessary after first tumor removal by a suboccipital approach, due to the progression of disease. Finally, neurological condition was much improved without remnant tumor although some sequelae were remained. We report this interesting case because of its rarity, complex clinical presentation, and challenge in its management.

Primary Malignant Melanoma in the Fourth Ventricle: Case Report

We describe a case of primary malignant melanoma in the fourth ventricle treated with surgery and fractionated high dose radiotherapy. A 27-year-old man was referred to our institution due to drowsy mentality, dysconjugated gaze, and pupil dilatation following vertigo and posterior neck pain. Preoperative magnetic resonance images revealed a fourth ventricular tumor extending to C2 level. The mass was high-signal intensity on T1-weighted image, low- on T2-weighted and homogeneous strong enhancement. Extraneural focus of primary site was not found. After grossly total removal in two staged operations, fractionated high dose radiotherapy was given(6300 cGy, 180cGy X 35 fraction). No tumor recurrence was seen for 12 months after operation. Aggressive treatment involving operative total tumor removal and combined radiotherapy is considered to increase the life span of the patient even with this type of tumor.

Clinical Analysis of Re-Operation after Thoracic and Lumbar Spinal Fusion Surgery

OBJECTIVE: The purpose of this study is to review retrospectively 28 patients with re-operation due to complications related to instrumentation from thoracic and lumbar spinal fusion surgery. METHODS: A total of 285 patients underwent spinal fusion surgery with instrumentation between 1996 and 2000. Of these, 11 men and 17 women(mean age 46 years, range 21 to 69 years) presented with complications related to instrumentation. Previous surgery was preformed for vertebral column instability secondary to fracture(4), spondylolisthesis(12), failed back surgery syndrome(7), osteomyelitis(1), herniated nuclus pulposus(4). All patients underwent repeated spinal surgery including removal of instrument, new instrument fixation, or I & D. The mean follow-up period after second operation was 19 months. RESULTS: The complications related instrumentation system include six interbody fusion system retropulsion, eight screw loosenings, five screw fractures, three screw malpositions, three osteomyelitis, and one donor site infection. After repeated surgery, eight became asymptomatic and did not require further treatment, but eleven showed persistent low back pain without neurological deficits and the remaining nine continued to have nerve root deficits. CONCLUSION: In conclusion, spinal fusion surgery with instrumentation offers an immediate postoperative stability of the thoracic and lumbar spine and enhances early fusion. However, it may be associated with few, but significant, complications which may permanantly. The proper selection of patients and meticulous surgical technique for surgery are probably the most important factors associated good outcomes and prevention of complications.

Outcome of Postoperative Intratumoral Bleomycin Injection for Cystic Craniopharyngioma

Total excision is a treatment of choice in preventing the relapse of craniopharyn-gioma, but for tumors involving an extensive area, it is often associated with an increased risk of complications. We have performed a partial or subtotal tumor removal followed by repeated injection of bleomycin into the remaining tumor through a subcutaneous reservoir as postoperative adjuvant therapy. A retro-spective review of clinical, radiological, and surgical data was performed for 10 patients (5 males and 5 females; age, 3-65 yr; follow-up duration, 12-79 months) with cystic craniopharyngiomas. The measurements of lactate dehydrogenase (LDH) level at each aspiration were performed. The shrinkage and/or stabiliza-tion of tumor was initially noted in all cases. The recurrence of tumor was seen in 4 cases (40%). The decreased or increased level of LDH was interpreted as tumor shrinkage or recurrence, respectively. The transient toxic reactions were observed in 3 patients (30%). Our study demonstrates that postoperative bleo-mycin injection for cystic craniopharyngioma, although does not appear to eradi-cate the tumor, decreases and stabilizes the tumor size, when used as an adju-vant therapy in young patients.

Prognostic Factors in the Treatment of Anterior Communicating Artery Aneurysms

OBJECTIVE: The anterior communicating artery(ACoA) is known to be the most frequent location of intracranial aneurysms, but the complex arterial anatomy of the ACoA region makes this aneurysm among the most difficult one to treat. In the treatment of ACoA aneurysms, the direction of aneurysmal fundus is known to be very important in the surgical tactics. All ACoA aneurysms in our series were classified according to its direction, and analyzed the clinical features in order to investigate the prognostic factors influencing upon the surgical outcome. METHODS: The authors reviewed 236 cases of ruptured ACoA aneurysms that were operated from 1990 to 1997, were classified according to Pia's classification. RESULTS: The incidence rate of the ACoA aneurysm was 35.1%(236/672). Ventral group was more common than dorsal group, especially in ventro-caudal projection subgroup(36.0%). Poor preoperative clinical grade(Hunt-Hess grade IV and V) patients were more common in dorsal group(13.1%) than ventral group(2.6%). Rebleeding and intracerebral hematoma were more commonly seen in ventral group. However, vasospasm, hydrocephalus, hyponatremia, and intraventricular hemorrhage were observed more frequently in dorsal group. Worse outcome was more common in dorsal group than ventral group, especially in dorso-caudal projection subgroup. Also, poor outcome was identified in patients with intracerebral hematoma, intraventricular hemorrhage, hyponatremia, and hypertension, although statistically insignificant. In cases with the A1 dominancy, there was no difference in surgical outcome between the right and left side approach. The higher the aneurysmal neck from the planum sphenoidale, the worse outcome via pterional approach. CONCLUSION: It seems that the preoperative clinical grade, aneurysmal direction, and the height of aneurysmal neck, especially in the pterional approach, would be the major prognostic factors, and that intracerebral hematoma, intraventricular hemorrhage, hyponatremia, hydrocephalus and the intraoperative aneurysmal rupture would be the minor prognostic factors.

Treatment Results of Intracranial Aneurysms by Wrapping and Coating

OBJECTIVE: Although surgical clipping of intracranial aneurysm is the definite method of treatment, there remains a small number of patients in whom surgical clipping is not technically possible. In such difficult cases, surgeon has to consider other therapeutic alternatives. In this report, we analyze our aneurysmal cases treated by wrapping and coating method and evaluate their surgical outcome and follow-up results. METHOD: Among the total of 877 patients operated from 1990 to 1999 for intracranial aneurysms at our hospital, 40 cases(4.6%) were treated by wrapping and coating method. They included 24 cases of single ruptured aneurysms and 16 with unruptured ones in multiple aneurysms. Wrapping with temporalis muscle and/or muslin gauze and coating with bioadhesive agent such as fibrin glue were performed. RESULT: Wrapping and coating method was performed mostly to the anterior communicating artery aneurysm (35%), and mostly because of the broad-based neck of an aneurysm(43%). At the time of discharge, 30 out of 40 patients(80%) showed favourable outcome and three cases died. The patients were monitored for average of 37 months(3-75 months). Among 24 cases with single ruptured aneurysm, 4 cases(17%) had early rebleeding within 6 months from the initial hemorrhage, and such rebleeding occurred within the first postoperative month in 3 cases. However, there was no rebleeding after the 6 months. Among 16 patients whose aneurysms were unruptured ones, none of them showed bleeding episode. CONCLUSION: It seems likely that the wrapping and coating method would be some help to prevent the rebleeding of an intracranial aneurysm. In order to obtain more accurate results regarding the efficacy of such method, it will be necessary to perform a multi-center study for longer follow-up periods and various wrapping and coating materials.

Primary Spinal Epidural Lymphoma Mimicking Epidural Abscess in a Diabetic

Primary spinal epidural lymphoma(SEL), i.e. occurring in the absence of any detectable extraspinal lymphoproli-ferative disorder, is an unusual cause of spinal cord compression. The authors report a 48-year-old, diabetic woman presented with back pain followed by acute paraparesis and voiding difficulty. She had been treated with acupunctures on her back before admission, and complete blood count showed leukocytosis with neutrophilia and increased erythrocyte sedimentation rate(ESR). Thoracic spine magnetic resonance imaging(MRI) revealed an epidural mass extending from T5 to T8 with compression of the spinal cord. Emergency decompressive laminectomy was performed with a tentative diagnosis of spinal epidural abscess, but a B-cell lymphoma was final pathologic diagnosis. Further staging showed no other sites of lymphoma, and the spinal lesion was treated by chemotherapy and radiotherapy. The authors stress that primary SEL can mimic spinal epidural abscess(SEA) in the diabetic patient and should be a diagnostic consideration in patients with a syndrome of acute spinal cord compression manifested by a prodrome of back pain and neuroimaging consistent with an epidural compressive lesion, especially in a diabetic.