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ABSTRACT: A 28-year-old male presented with a rare case of primary intramedullary spinal Langerhans cell histiocytosis (LCH) manifesting as the chief complaint of a 6-month history of gait disturbance and back pain, and difficulty with sphincter control. Serial T2-weighted magnetic resonance imaging of the thoracic spine revealed enlargement and intramedullary hyperintensity of the spinal cord at T2 to T4. Biopsy of the lesion was performed. Histological examination of the biopsy specimens verified vascular proliferation and remarkable infiltration of histiocytes that were positive for CD1a, suggesting a diagnosis compatible with LCH. The patient was treated successfully by steroid pulse therapy. LCH is a rare disease that occurs mainly in children and may cause a broad range of manifestations, from a single osseous lesion to multiple lesions involving more than one organ or system. The present case illustrates the unexpected occurrence and important differential diagnosis of primary intramedullary spinal LCH of the thoracic spine in adult patients presenting with progressive paraparesis and back pain.
Neurologia medico-chirurgica 01/2013; 53(4):245-8. · 0.61 Impact Factor
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ABSTRACT: Cervical intervertebral disc replacement using a rectangular titanium stand-alone cage has become a standard procedure for anterior cervical discectomy and fusion (ACDF). We examined outcomes resulting from the contemporary use of rectangular titanium stand-alone cages for ACDF, particularly focusing on cage subsidence and subsequent kyphotic malalignment. Patient data were collected prospectively, and a total of 47 consecutive patients who underwent periodic follow-up of at least 1year's duration after ACDF were studied retrospectively. Sixty-three rectangular titanium cages were implanted during 31 1-level and 16 2-level procedures. None of the patients developed surgery-related complications (including cage displacement or extrusion). Mean Neurosurgical Cervical Spine Scale scores were significantly improved at 1year after surgery. Twelve of the 63 inserted cages (19.0%) were found to have cage subsidence, occurring in 11 of 47 patients (23.4%). There was no significant difference in functional recovery between patients with and without cage subsidence. Logistic regression analysis indicated that fusion level, cage size and cage position were significantly related to cage subsidence. The distraction ratio among patients with cage subsidence was significantly higher than that among patients without cage subsidence. Cage subsidence resulted in early deterioration of local angle and total alignment of the cervical spine. Although a longer follow-up is warranted, a good surgical outcome with negligible complications appears to justify the use of rectangular titanium stand-alone cages in 1- and 2-level ACDF. Excessive distraction at the fusion level should be avoided, and cage position should be adjusted to the anterior vertical line.
Journal of Clinical Neuroscience 10/2012; · 1.25 Impact Factor
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ABSTRACT: Study Design: Cross-sectional studyObjective: To assess spinal cord condition in patients with cervical spondylosis (CS) using diffusion tensor (DT) imaging parameter.Summary of Background Data: Although myelopathy is a common symptom following CS, clinically objective assessment for determination of surgical intervention is not straightforward.Methods: Twenty-six patients with CS and 30 normal control subjects were enrolled. DT imaging was obtained using a single-shot fast spin-echo-based sequence at 3.0 T. Mean diffusivity (MD) and fractional anisotropy (FA) were measured in the axial plane at six spinal levels. To evaluate MD and FA in the patients with CS considering the normal variation at each spinal level and between spinal levels, MD and FA at the most compressed spinal level were transformed to normalized values with a z-score. Presence of myelopathy was predicted with the MD and FA z-scores. Diagnostic validity of MD and FA was compared with receiver operating characteristic (ROC) analysis. More effective parameter and the optimal cut-off value for prediction were determined.Results: In normal subjects, MD and FA were significantly different between spinal levels. In patients with myelopathy, an MD increase or an FA decrease was demonstrated in most cases. Although both an MD increase and an FA decrease had diagnostic validity for myelopathy, receiver operating characteristic (ROC) analysis demonstrated a higher sensitivity and specificity for prediction of an MD increase than an FA decrease (areas under the curve for MD and FA were 0.903 and 0.760, respectively). An MD z-score of 1.40 was considered to be the best diagnostic cut-off value with 100% sensitivity and 75% specificity.Conclusions: Myelopathy can be predicted with high accuracy with DT imaging parameter with the MD z-score at the most compressed spinal level.
Spine 08/2012; · 2.08 Impact Factor
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ABSTRACT: Study Design. This is technical case reports of direct surgery for spinal arteriovenous fistulas (AVFs) of the filum terminale.Objective. We present two cases of spinal AVFs of the filum terminale directly fed by the anterior spinal artery that were successfully obliterated with intraoperative image guidance such as digital subtraction angiography, intra-arterial (IA) dye injection technique or indocyanine green (ICG) video angiography.Summary of Background Data. The goal of direct surgery for spinal AVFs is the complete obliteration of shunt vessels while preserving the normal circulation of spinal cord. Safe isolation of feeding arteries, nidus and draining veins needs to be first obtained. Vascular flow or anatomical orientation of shunt vessels also needs to be ensured with intraoperative image guidance.Methods. Two cases are presented. The first patient (Case 1) had the lesion with a nidus formation at the L2 spinal level supplied directly by the anterior spinal artery via the left L1 segmental artery. The second patient (Case 2) had a lesion at the L4/5 spinal level also supplied directly by the anterior spinal artery via the left T11 intercostal artery. Standard exposure of the lesion followed intraoperative image guidance to achieve the appropriate vascular flow or anatomical orientation of the shunt vessels.Results. Complete obliteration of shunt vessels was successfully achieved without any complications in both cases.Conclusion. Although intraoperative image guidance is certainly not a prerequisite, the concept of safe and minimally invasive surgery makes it indispensable. It can facilitate identification of crucial or important landmarks where anatomic structures may be distorted.
Spine 08/2012; · 2.08 Impact Factor
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ABSTRACT: OBJECTIVE: To categorize clinoidal meningiomas according to their venous drainage patterns, and use each category as a guideline to establish an appropriate surgical strategy. METHODS: We performed a retrospective analysis of 22 consecutive surgically treated patients with clinoidal meningioma who underwent preoperative digital subtraction angiography to examine the characteristics of the venous drainage system. These patients were categorized into: 1) cortical type in which the sylvian vein did not drain medially but drained to cortical veins, 2) sphenobasal type in which the sylvian vein drained into the pterygoid plexus, or 3) cavernous type in which the sylvian vein drained into the cavernous sinus directly through the sphenoparietal sinus. We tailored the surgical strategy to preserve these draining veins. RESULTS: Preoperative angiographic evaluation demonstrated 14 patients (63.6%) with cortical type, 6 patients (27.3%) with sphenobasal type, and 2 patients (9.1%) with the cavernous type. In most cases, no restriction from the venous structure was observed because the sylvian vein belonged to the cortical type. However, in the case of the sphenobasal or sphenoparietal type, the surgical strategy seemed to be tailored to preserve the venous drainage system. CONCLUSIONS: The surgical risk from venous complication in the treatment of clinoidal meningiomas appears to be low; however, there are likely to be patients that require a tailored surgical approach to avoid venous complications. Detailed preoperative assessment of anatomic structure and consideration of the optimal surgical strategy are critical to improve treatment outcomes.
World Neurosurgery 11/2011; · 0.68 Impact Factor
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ABSTRACT: We present a rare case of medulloblastoma which presented with unilateral sudden sensorineural hearing loss as an initial symptom. A 19-year-old man was admitted to our hospital with a chief complaint of dizziness and facial numbness on the right side. His illness had begun two years previously with sudden hearing loss on the right side, for which he had been treated as an idiopathic sudden hearing loss. Magnetic resonance imaging demonstrated abnormal signals located mainly in the right middle cerebellar peduncle. We performed partial resection of the tumor by suboccipital craniotomy. The histopathological diagnosis was medulloblastoma. Intrinsic brain tumor is an extremely rare cause of sudden sensorineural hearing loss and is therefore easily overlooked as was in the present case. The present case highlights not only the need to evaluate patients with sudden sensorineural hearing loss by magnetic resonance imaging but also the importance of paying attention to intrinsic lesions involving the brainstem. Although this condition like the presented case might be rare, intrinsic brain tumor should be considered as a potential cause of sudden sensorineural hearing loss, as it may be easily missed leading to a delay in appropriate treatment.
Journal of Korean Neurosurgical Society 07/2011; 50(1):51-3. · 0.60 Impact Factor
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ABSTRACT: The purpose of this study was to characterize the imaging spectrum of benign notochordal cell tumors (BNCTs) and chondromas and to determine if this helped in differentiating BNCTs from chordomas.
Thirty-eight patients pathologically diagnosed with chordomas were reviewed and ultimately diagnosed to have five BNCTs and 33 chordomas. The following radiologic findings were reevaluated by two radiologists by consensus: extraosseous extension, osseous change on CT or conventional tomography, T2-weighted MR signal intensity, T2-weighted signal homogeneity, and contrast-enhanced T1-weighted MR signal intensity. Fisher's exact test was performed to determine statistical significance.
Our study yielded five results. First, four of five BNCTs (80%) were intraosseous, whereas 31 of 33 chordomas (94%) were both intra- and extraosseous (p < 0.0001). Second, all BNCTs showed mild osteosclerosis without bone destruction; all chordomas showed variable osteolysis (p = 0.0092). Third, all BNCTs and 28 of 33 chordomas (85%) showed hyperintensity on T2-weighted images (p > 0.05). Fourth, four of five BNCTs (80%) and 27 of 33 chordomas (82%) were heterogeneous on T2-weighted images (p > 0.05). Fifth, no BNCTs enhanced, whereas all chordomas variably enhanced (p < 0.0001).
Radiologic studies may allow distinction of BNCTs from chordomas.
American Journal of Roentgenology 03/2011; 196(3):644-50. · 2.78 Impact Factor
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ABSTRACT: Clival lesions remain one of the most challenging intracranial tumors to treat surgically. Many skull base approaches have been described to improve resection and to decrease patient morbidity.
To describe a middle skull base approach with posterolateral mobilization of the geniculate ganglion of the facial nerve to access the clival regions.
Three patients with petroclival chordoma and 1 patient with petroclival meningioma underwent surgical resection of lesions with our new procedure. Surgical techniques consisted of temporal craniotomy and exposure of the facial nerve from the tympanic segment to the labyrinthine segment, keeping the fundus of the internal auditory canal intact. The geniculate ganglion was mobilized posterolaterally, followed by drilling of the cochlea and exposure of the Dorello canal.
Four lesions were successfully removed with complete preservation of facial nerve function.
This approach is a modification of the Goel procedure in which the facial nerve from the tympanic segment to the cisternal segment was totally mobilized. Our procedure carries less risk to the facial nerve function than the Goel procedure and provides sufficiently wide exposure of clival lesions.
Neurosurgery 02/2011; 69(1 Suppl Operative):ons88-94; discussion ons94. · 2.79 Impact Factor
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ABSTRACT: The aim of this study was to determine the uptake of L-[methyl-(11)C]-methionine ((11)C-MET) in the normal brain of patients younger than 20 y, to facilitate more accurate diagnoses in young patients.
Eighty-two patients were categorized into 4 groups according to their age. They underwent (11)C-MET PET, and a standardized uptake value (SUV) was determined for different brain regions including the frontal lobe, parietal lobe, cerebellum, and brain stem.
Compared with all other parts of the brain, the cerebellum had the highest SUV. A tendency for a positive relationship between SUV and age was found in all regions, and a significant relationship with SUV was found in the frontal lobe and cerebellum.
The character of SUV in the normal brains of children is different from that of adults, and these normal SUV data will play an important role as a critical reference value.
Journal of Nuclear Medicine 02/2011; 52(2):201-5. · 6.38 Impact Factor
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ABSTRACT: A 50-year-old male presented with a rare case of hemangioblastoma of cauda equina origin, without clinical signs of von Hippel-Lindau syndrome, manifesting as pain radiating from the back to the left thigh. Magnetic resonance imaging before surgery revealed an intradural spinal tumor at the L3-L4 levels with serpentine flow voids of tortuous and convoluted vessels, which appeared to be continuous with the left L5 nerve root. Surgical removal of the tumor was successfully accomplished via the posterior unilateral approach, and the histological diagnosis was hemangioblastoma. Clinical symptoms resolved dramatically after surgery, although the patient developed mild dysesthesia of the left L5 area early after surgery which was gradually improved late after surgery.
Neurologia medico-chirurgica 01/2011; 51(10):732-5. · 0.61 Impact Factor
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ABSTRACT: Although adhesive arachnoiditis of the spinal cord can cause progressive symptoms associated with syringomyelia or myelomalacia, its surgical resolution based on the imaging diagnosis is not well characterized. This study aims to describe the use of imaging for the diagnosis of focal adhesive arachnoiditis of the spinal cord and its surgical resolution using microsurgical arachnoidolysis.
Four consecutive patients with symptomatic syringomyelia or myelomalacia caused by focal adhesive arachnoiditis underwent microsurgical arachnoidolysis. Comprehensive imaging evaluation using constructive interference in steady-state (CISS) magnetic resonance imaging (MRI) or myelographic MR imaging using true fast imaging with steady-state precession (TrueFISP) sequences was included before surgery to determine the surgical indication.
In all four patients a focal adhesion was identified at the cervical or thoracic level of the spinal cord, a consequence of infection or trauma. Three patients showed modest or minor improvement in neurological function, and one patient was unchanged after surgery. The syringomyelia or myelomalacia resolved after surgery and no recurrence was noted within the follow-up period, which ranged from 5 months to 30 months.
MRI diagnosis of focal adhesive arachnoiditis is critical to determine the surgical indication. Microsurgical arachnoidolysis appears to be a straightforward method for stabilizing the progressive symptoms, though the procedure is technically demanding.
Journal of craniovertebral junction and spine 07/2010; 1(2):100-6.
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ABSTRACT: Safe and complete surgical resection of brainstem cavernoma is difficult without injury surrounding normal structures because the lesions are deep and intra-axial. In this article, the authors describe the "microroll retractor" technique for brainstem cavernoma surgery.
The microroll retractor is made of expanded polytetrafluoroethylene sheet. The sheet is cut in several sizes of square piece and transformed into a tubular shape. We insert this roll retractor via minimal brain incision and keep surgical corridor without usual spatulas during lesionectomy.
This technique was adopted for 7 patients with brainstem cavernomas. In all patients, we achieved total excision; improvement was recorded in 6 patients, and no change was recorded in 1 patient.
The microroll retractor is extremely simple but provides enough surgical corridors for safe total resection of brainstem cavernomas.
World Neurosurgery 05/2010; 73(5):520-2. · 0.68 Impact Factor
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ABSTRACT: Because resection followed by timely stereotactic radiosurgery (SRS) is becoming a standard strategy for skull base meningiomas, the role of initial surgical tumor reduction in this combined treatment should be clarified.
This study examined 161 patients with benign skull base meningiomas surgically treated at Osaka City University between January 1985 and December 2005. The mean follow-up period was 95.3 months. Patients were categorized into 3 groups based on the operative period and into 4 groups based on tumor location. Maximal resection was performed as first therapy throughout all periods. In the early period (1985-1994), in the absence of SRS, total excision of the tumor was intentionally performed for surgical cure of the disease. In the mid and late periods (1995-2000 and 2001-2005), small parts of the tumor invading critical neurovascular structures were left untouched to obtain good functional results. Residual tumors with high proliferation potential (Ki 67 index > 4%) or with progressive tendencies were treated with SRS. The extent of initial tumor resection, recurrence rate, Karnofsky Performance Scale score, and complication rate were investigated in each group.
The mean tumor equivalent diameter of residual tumors was 3.67 mm in the no-recurrence group and 11.7 mm in the recurrence group. The mean tumor resection rate (TRR) was 98.5% in the no-recurrence group and 90.1% in the recurrence group. A significant relationship was seen between postoperative tumor size, TRR, and recurrence rate (p < 0.001), but the recurrence rate showed no significant relationship with any other factors such as operative period (p = 0.48), tumor location (p = 0.76), or preoperative tumor size (p = 0.067). The mean TRR was maintained throughout all operative periods, but the complication rate was lowest and postoperative Karnofsky Performance Scale score was best in the late period (p < 0.001 each). Late-period results were as follows: mean TRR, 97.9%; mortality rate, 0%; and severe morbidity rate, 0%. Stereotactic radiosurgery procedures were added in 27 cases (16.8%) across all periods. Throughout all follow-up periods, 158 tumors were satisfactorily controlled by maximal possible excision alone or in combination with adequate SRS.
The combination of maximal possible resection and additional SRS improves functional outcomes in patients with skull base meningioma. A TRR greater than 97% in volume can be achieved with satisfactory functional preservation and will lead to excellent tumor control in combined treatment of skull base meningioma.
Journal of Neurosurgery 03/2010; 113(5):1072-8. · 2.96 Impact Factor
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ABSTRACT: The aim of this study was to determine the normal l-[methyl-(11)C]-methionine ((11)C-methionine) uptake and the extent of variation using standardized uptake value (SUV).
Five healthy volunteers and 58 adult patients with normal (11)C-methionine uptake were included in the interindividual analysis and 22 patients in the intraindividual analysis. SUVs in different brain regions, age-associated changes, correlation between 2 correction methods (for body weight [w-SUV] or body surface area [s-SUV]), and intraindividual reproducibility were examined.
w-SUVs were statistically different between the brain regions. The frontal or parietal cortex showed lower coefficients of variation than did the cerebellum or brain stem. There was no significant age-associated change. w-SUVs showed lower coefficients of variation in interindividual analysis and lower symmetric percentage change in intraindividual reproducibility than did s-SUVs.
SUVs in the normal brain show inter- and intraindividual variation, and our proposed normal w-SUVs represent an important reference value.
Journal of Nuclear Medicine 02/2010; 51(2):219-22. · 6.38 Impact Factor
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ABSTRACT: Spinal nerve sheath tumors (NSTs) originating from the C1 or C2 level are unique from both anatomical and clinical perspectives. Surgical technique to accomplish radical but safe resection of these tumors is described in 8 cases treated during the past 5 years. Surgical measures included positioning the patient in the lateral oblique position, unilateral posterior approach, exposure of the tumor along the surgical plane of the dural or perineural boundary, and proximal and distal amputation of the tumor with resection of dural penetration. Excessive bone resection and soft tissue manipulation were unnecessary. Microscopic complete removal of the tumor was accomplished in seven of eight cases. Subtotal resection was done in one case where the tumor extended beyond the vertebral artery. Functional assessment demonstrated satisfactory improvement after surgery in all cases. Surgery-related complications were not encountered in any case. Exposure of the tumor along the surgical plane of the dural or perineural boundary may be the key procedure required to accomplish radical but safe resection of spinal NSTs originating from the C1 or C2 level.
Neurologia medico-chirurgica 01/2010; 50(11):1044-9. · 0.61 Impact Factor
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ABSTRACT: A 25-year-old male patient presented with an extremely rare primary spinal peripheral primitive neuroectodermal tumor (pPNET) manifesting as acutely progressive paraparesis and back pain. Neuroimaging and intraoperative examination showed that the tumor was confined to the epidural space of the thoracic spine. The patient was treated successfully by gross total resection of the tumor followed by chemotherapy and local radiotherapy. The present case illustrates the unexpected occurrence and important differential diagnosis of primary epidural pPNET of the thoracic spine in young patients presenting with progressive paraparesis and back pain.
Neurologia medico-chirurgica 11/2009; 49(11):542-5. · 0.61 Impact Factor
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ABSTRACT: BACKGROUND: Safe and complete surgical resection of brainstem cavernoma is difficult without injury surrounding normal structures because the lesions are deep and intra-axial. In this article, the authors describe the "microroll retractor" technique for brainstem cavernoma surgery. METHODS: The microroll retractor is made of expanded polytetrafluoroethylene sheet. The sheet is cut in several sizes of square piece and transformed into a tubular shape. We insert this roll retractor via minimal brain incision and keep surgical corridor without usual spatulas during lesionectomy. RESULTS: This technique was adopted for 7 patients with brainstem cavernomas. In all patients, we achieved total excision; improvement was recorded in 6 patients, and no change was recorded in 1 patient. CONCLUSIONS: The microroll retractor is extremely simple but provides enough surgical corridors for safe total resection of brainstem cavernomas.
Surgical Neurology 09/2009; · 1.67 Impact Factor
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ABSTRACT: A 64-year-old man presented with spinal schwannoma of the cauda equina at the thoraco-lumbar junction manifesting as acute paraparesis and urinary incontinence after intratumoral hemorrhage. Surgical resection of the tumor resulted in significant neurological recovery. T(2)(*)-weighted gradient-echo magnetic resonance imaging is very useful to help establish the preoperative diagnosis, leading to early surgical intervention and better outcome after surgery.
Neurologia medico-chirurgica 07/2009; 49(6):255-7. · 0.61 Impact Factor
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ABSTRACT: Two patients presented with primary intramedullary spinal cord germinoma (PISCG). Neither diagnosis was correct at initial evaluation, and both underwent surgical verification of the tumor. Based on the histological diagnosis, both patients were treated successfully by combination of chemotherapy and radiotherapy. These cases illustrate the unexpected occurrence of PISCG and treatment strategy.
Neurologia medico-chirurgica 04/2009; 49(3):128-33. · 0.61 Impact Factor
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ABSTRACT: Occipitocervical fusion with the head in a functionally neutral position is critically important. Various methods have been proposed for measuring the angle of the craniovertebral junction based on lateral radiography. We describe a simple and reliable measurement of fixation angle during occipitocervical fusion using the line parallel to the bony palate and the posterior longitudinal line of the C2 vertebra. The normal range of the angle of the craniovertebral junction was measured in 30 normal healthy volunteers, 15 males and 15 females aged from 17 to 77 years (mean 45.1 years), without symptoms of neck pain or limitations of neck movement. The angle ranged from 85 to 118 degrees. The mean angle was 97.1 degrees in males and 102.6 degrees in females, with overall mean +/- standard deviation of 99.9 +/- 8.1 degrees. Careful adjustment of the angle of the craniovertebral junction can help to avoid postoperative complications such as dysphagia, dyspnea, and subaxial subluxation.
Neurologia medico-chirurgica 07/2008; 48(6):279-82; discussion 282. · 0.61 Impact Factor
