Application and Advantages of the Trans-Unco-Discal (TUD) Approach for Cervical Spondylotic Myelopathy and Radiculopathy: Classification and Modification of Surgical Technique Based on the Location of Spinal Cord and/or Nerve Root Compression.

We assess the application and advantages of modifying the trans-unco-discal (TUD) approach which we underwent for cervical myelo-radiculopathy. We present the surgical techniques of the modified TUD approach. The material was 180 cases where anterior cervical decompression (ACD) was performed by the modified TUD approach.

Parent Artery Occlusion for a Dissecting Posterior Cerebral Artery Aneurysm in the P4 Segment Presenting with Ischemic Stroke and Rapid Growth: A Case Report.

A dissecting aneurysm in the P4 segment of the posterior cerebral artery (PCA) is extremely rare, and its treatment is sometimes challenging. Endovascular parent artery occlusion (PAO) was performed for an unruptured P4 segment dissecting PCA aneurysm presenting with ischemic stroke and rapid growth. A 70-year-old man was rushed to our emergency department due to a right-sided headache and a visual field defect.

The Symptomatic Calcification and Ossification of the Ligamentum Flavum in the Spine: Our Experience and Review of the Literature.

Introduction: We report our experience regarding the clinical features and pathological findings of the calcification of the ligamentum flavum (CLF) and ossification of the ligamentum flavum (OLF) in the spine. In addition, we reviewed the previous studies on CLF and OLF to enhance the understanding of these conditions.

Materials And Methods: We compared the clinical, radiological, and histopathological features of CLF and OLF.

Surgical Management of Chiari Malformation Type I and Instability of the Craniocervical Junction Based on Its Pathogenesis and Classification.

We investigated the mechanism underlying Chiari malformation type I (CM-I) and classified it according to the morphometric analyses of posterior cranial fossa (PCF) and craniocervical junction (CCJ). Three independent subtypes of CM-I were confirmed (CM-I types A, B, and C) for 484 cases and 150 normal volunteers by multiple analyses. CM-I type A had normal volume of PCF (VPCF) and occipital bone size.

Two-stage posterior decompression and fusion for tuberculous spondylitis after intravesical bacillus Calmette-Guerin instillation.

Intravesical bacillus Calmette-Guerin (BCG) instillation is an effective treatment for nonmuscle invasive superficial bladder cancer. BCG induces a massive influx of inflammatory cells and production of cytokines in the bladder mucosa and lumen that leads to an immune response against tumor cells, acting as an immunotherapy. Cystitis, bladder ulceration, and bladder contracture are known local genitourinary complications, whereas systemic complications such as miliary pulmonary tuberculosis, mycotic aneurysms, tuberculous spondylodiscitis, and granulomatous hepatitis are very rare.

Pathogenesis and Classification of Chiari Malformation Type I Based on the Mechanism of Ptosis of the Brain Stem and Cerebellum: A Morphometric Study of the Posterior Cranial Fossa and Craniovertebral Junction.

 We investigated the mechanism of ptosis of the brain stem and cerebellum (hindbrain) in Chiari malformation type I (CM-I) and classified CM-I according to pathogenesis, based on a morphometric study of the posterior cranial fossa (PCF) and craniovertebral junction (CVJ). We discuss the appropriate surgical treatment for hindbrain ptosis.  We examined 500 patients with CM-I and 100 healthy control individuals.

Surgical Management of Chiari Malformations: Preliminary Results of Surgery According to the Mechanisms of Ptosis of the Brain Stem and Cerebellum.

 We classified Chiari malformation type I (CM-I) according to the mechanism of ptosis of the brain stem and cerebellum, based on a morphometric study of the posterior cranial fossa (PCF) and craniovertebral junction (CVJ). Surgery was performed to manage the mechanism of the hindbrain ptosis.  We calculated the volume of the PCF (VPCF) and the area surrounding the foramen magnum (VSFM) and measured the axial length of the enchondral parts of the occipital bone (occipital bone size) and the hindbrain.

Safety of anterior cervical discectomy and fusion using titanium-coated polyetheretherketone stand-alone cages: Multicenter prospective study of incidence of cage subsidence.

This multicenter prospective study investigated cage subsidence in anterior cervical discectomy and fusion (ACDF) using titanium-coated polyetheretherketone (PEEK) stand-alone cages. This study recruited patients who underwent 1- or 2-level ACDF using titanium-coated PEEK stand-alone cages for cervical disc disease. Patients with acute trauma or past cervical spine operations were excluded.

Mechanisms of cerebellar tonsil herniation in patients with Chiari malformations as guide to clinical management.

Background: The pathogenesis of Chiari malformations is incompletely understood. We tested the hypothesis that different etiologies have different mechanisms of cerebellar tonsil herniation (CTH), as revealed by posterior cranial fossa (PCF) morphology.

Methods: In 741 patients with Chiari malformation type I (CM-I) and 11 patients with Chiari malformation type II (CM-II), the size of the occipital enchondrium and volume of the PCF (PCFV) were measured on reconstructed 2D-CT and MR images of the skull.

Association of Chiari malformation type I and tethered cord syndrome: preliminary results of sectioning filum terminale.

Objective: The pathogenesis of CM-I is incompletely understood. We describe an association of CM-I and TCS that occurs in a subset of patients with normal size of the PCF.

Methods: The prevalence of TCS was determined in a consecutively accrued cohort of 2987 patients with CM-I and 289 patients with low-lying cerebellar tonsils (LLCT).

Syndrome of occipitoatlantoaxial hypermobility, cranial settling, and chiari malformation type I in patients with hereditary disorders of connective tissue.

Object: Chiari malformation Type I (CM-I) is generally regarded as a disorder of the paraxial mesoderm. The authors report an association between CM-I and hereditary disorders of connective tissue (HDCT) that can present with lower brainstem symptoms attributable to occipitoatlantoaxial hypermobility and cranial settling.

Methods: The prevalence of HDCT was determined in a prospectively accrued cohort of 2813 patients with CM-I.

Posterior C1-2 Fixation with cancellous screw and rod system for retro-odontoid pseudotumor associated with chronic atlantoaxial subluxation. Technical note.

Posterior C1-2 fixation with individual screw placement in C-1 and C-2 was performed in three patients presenting with progressive myelopathy caused by retro-odontoid pseudotumor associated with chronic atlantoaxial subluxation. Postoperatively, all patients demonstrated neurological recovery with gradually diminishing pseudotumor. Posterior C1-2 fixation with the cancellous screw and rod system is a safe and reliable method, and can be used to treat retro-odontoid pseudotumor associated with chronic atlantoaxial subluxation.

The anterolateral partial vertebrectomy approach for ventrally located cervical intramedullary cavernous angiomas.

Objective: We report three cases with ventral cervical intramedullary cavernous angiomas. An anterolateral partial vertebrectomy was performed to surgically approach and successfully resect these lesions.

Materials And Methods: All three patients presented with numbness in the upper extremities and investigation revealed a cavernous angioma on the ventral aspect of the spinal cord in each case.

Microsurgical interruption of dural arteriovenous fistula at the foramen magnum.

We report two rare cases of progressive congestive myelopathy caused by dural arteriovenous fistulae (DAVF) at the foramen magnum. The first, a 69-year-old male with a 2-year history of progressive myelopathy, had symptoms unrecognized due to a past history that included spinal caries and congenital dislocation of the hip. The second, a 60-year-old male, had a recurrence of the myelopathy three months after endovascular occlusion of the DAVF feeding artery.

Methionine positron emission tomography for differentiation of recurrent brain tumor and radiation necrosis after stereotactic radiosurgery--in malignant glioma.

Object: Following stereotactic radiosurgery (SRS), we examined how to differentiate radiation necrosis from recurrent malignant glioma using positron emission tomography (PET) with 11C-methionine (Met).

Methods: Met-PET scans were obtained from 11 adult cases of recurrent malignant glioma or radiation injury, suspected on the basis of magnetic resonance images (MRI). Patients had previously been treated with SRS after primary treatment.

Chiari I malformation associated with ventral compression and instability: one-stage posterior decompression and fusion with a new instrumentation technique.

Objective And Importance: We describe an alternative surgical technique for treatment of Chiari I malformation associated with ventral compression and instability of the region. An expansive suboccipital cranioplasty and a rigid occipitocervical fixation are performed in one stage.

Methods: The occipitocervical fixation is performed by use of metal rods fixed on the cranial side by screws inserted into the diploic layer of occipital bone and on the caudal side by screws inserted into the pedicle of the axis or in a transarticular fashion into the lateral masses of axis and atlas vertebra.

Prevention of postoperative posterior tethering of spinal cord after resection of ependymoma.

Object: The authors evaluated an alternative method to avoid postoperative posterior tethering of the spinal cord following resection of spinal ependymomas.

Methods: Twenty-five patients with spinal ependymoma underwent surgery between 1978 and 2002. There were 16 male and nine female patients whose ages at the time of surgery ranged from 14 to 64 years (mean 41.

Transposition of the oculomotor nerve for resection of a midbrain cavernoma. Technical note.

The authors discuss the utility of anterior transposition of the oculomotor nerve from the lateral wall of the cavernous sinus to widen the corridor posterior to the cisternal segment of the oculomotor nerve; this allows exposure of the anterolateral surface of the midbrain. This additional exposure was successfully used for the resection of a large calcified cavernoma in the upper brainstem of a 67-year-old woman who had presented with sudden onset of left hemiparesis and oculomotor palsy. The patient's postoperative course was uneventful and she displayed symptomatic improvement.

The role of postoperative patient posture in the recurrence of chronic subdural hematoma: a prospective randomized trial.

Background: Chronic subdural hematoma is known to have a significant recurrence rate. In this report, we evaluate the relationship between the recurrence rate of chronic subdural hematoma and postoperative patient posture.

Methods: We conducted a prospective randomized study of 46 patients with chronic subdural hematoma treated surgically at the Osaka City General Hospital from January 1997 to December 1999.

Hydroxyapatite laminar spacers and titanium miniplates in cervical laminoplasty.

Objective: The authors describe a new surgical technique for cervical laminoplasty that was performed in 25 patients. The posterior elements along with the various ligaments are removed en bloc and are stabilized in a lift-up position by placing hydroxyapatite (HA) laminar spacers and titanium miniplates and screws. The procedure and clinical results are discussed.

Constructive interference in steady state imaging of moyamoya disease.

The diagnostic accuracy of three-dimensional constructive interference in steady state (CISS) magnetic resonance (MR) imaging was evaluated for the assessment of idiopathic moyamoya disease. Six consecutive patients underwent MR angiography, CISS imaging, and digital subtraction angiography. MR angiography and CISS imaging visualization of the steno-occlusive changes in the distal internal carotid arteries and the development of moyamoya vessels in the basal cistern were compared to the results obtained by digital subtraction angiography.