Microvascular Decompression for Glossopharyngeal Neuralgia in the Semi-Sitting Position: A Report of Two Cases.

The semi-sitting position is well known to neurosurgeons. However, there are few reports of microvascular decompression surgery for glossopharyngeal neuralgia performed using the semi-sitting position. The semi-sitting position is not widely adopted in Japan, but it is considered to be a very useful neurosurgical position. Microvascular decompression surgery for glossopharyngeal neuralgia is a relatively rare procedure, and the semi-sitting position is very effective, considering the possibility of intraoperative cardiac arrest and postoperative complications of lower cranial nerve palsy. This report describes two cases of glossopharyngeal neuralgia operated in the semi-sitting position. Microvascular decompression was performed on both patients, and postoperative pain controls were good and no complications were observed. We show that the use of the semi-sitting position to perform microvascular decompression for glossopharyngeal neuralgia provides an excellent surgical view of the brainstem.

Limitations of median nerve somatosensory evoked potential monitoring during carotid endarterectomy.

OBJECTIVE: Hypoperfusion during carotid artery cross-clamping (CC) for carotid endarterectomy (CEA) may result in the major complication of perioperative stroke. Median nerve somatosensory evoked potential (MNSSEP) monitoring, which is an established method for the prediction of cerebral ischemia, has low sensitivity in detecting such hypoperfusion. In this study the authors sought to explore the limitations of MNSSEP monitoring compared to tibial nerve somatosensory evoked potential (TNSSEP) monitoring for the detection of CC-related hypoperfusion. METHODS: The authors retrospectively analyzed data from patients who underwent unilateral CEA with routine shunt use. All patients underwent preoperative magnetic resonance angiography and were monitored for intraoperative cerebral ischemia by using MNSSEP, TNSSEP, and carotid stump pressure during CC. First, the frequency of MNSSEP and TNSSEP changes during CC were analyzed. Subsequently, variables related to stump pressure were determined by using linear analysis and those related to each of the somatosensory evoked potential (SSEP) changes were determined by using logistic regression analysis. RESULTS: A total of 94 patients (mean age 74 years) were included in the study. TNSSEP identified a greater number of SSEP changes during CC than MNSSEP (20.2% vs 11.7%; p < 0.05). Linear regression analysis demonstrated that hypoplasia of the contralateral proximal segment of the anterior cerebral artery (A1 hypoplasia) (p < 0.01) and hypoplasia of the ipsilateral precommunicating segment of the posterior cerebral artery (P1 hypoplasia) (p = 0.02) independently and negatively correlated with stump pressure. Both contralateral A1 hypoplasia (OR 26.25, 95% CI 4.52-152.51) and ipsilateral P1 hypoplasia (OR 8.75, 95% CI 1.83-41.94) were independently related to the TNSSEP changes. However, only ipsilateral P1 hypoplasia (OR 8.76, 95% CI 1.61-47.67) was independently related to MNSSEP changes. CONCLUSIONS: TNSSEP monitoring appears to be superior to MNSSEP in detecting CC-related hypoperfusion. Correlation with stump pressure and SSEP changes indicates that TNSSEP, and not MNSSEP monitoring, is a reliable indicator of cerebral ischemia in the territory of the anterior cerebral artery.

Delayed Postoperative Spinal Epidural Hematoma after Cervical Laminoplasty.

A 56-year-old man underwent cervical laminoplasty for cervical spondylosis. On the 7th postoperative day, he suddenly felt severe neck pain, and tetraplegia developed rapidly over 1.5 hrs. Computed tomography demonstrated a huge hematoma compressing the cervical spinal cord. Clot was evacuated 3 hrs after the onset of symptoms. The patient's postoperative course was uneventful. His blood pressure could not be properly controlled in the perioperative period. Surgeons should keep in mind that delayed postoperative spinal epidural hematoma (DPSEH) can occur more than a week after surgery, and meticulous blood pressure control is important for more than a week after a spinal operation.

Clinical Characteristics and Management of C3-4 Degenerative Cervical Myelopathy.

Single-level anterior cervical discectomy and fusion (ACDF) was performed at C3-4; non-C3-4 ACDF patients of the authors' random sample of ACDF patients were compared with C3-4 ACDF patients. The radiological study of C3-4 ACDF patients shows that they had significant cervical lordosis, and cervical motion was dependent on the C3-4 segment, which accounted for 39.8% of C2-7 range of intervertebral motion (total motion). In C3-4 ACDF patients, not only static factors but also dynamic factors (instability) at the C3-4 level contributed to the major causes of degenerative cervical myelopathy.

Radiological study of C3-C4 level surgical cases of cervical spondylosis.

OBJECTIVE: The purpose of this study was to elucidate the pathological characteristics of C3-C4 cervical spondylotic myelopathy (CSM) from the radiological study. MATERIALS AND METHODS: A total of 31 patients with single level anterior cervical discectomy and fusion (ACDF) at C3-C4 and 46 patients with single level ACDF at C5-C6 were included in this study. We selected C5-C6 level as a representative of the lower cervical level. The C3-C4 and C5-C6 levels were routinely examined to investigate the areas of the vertebral canal, subarachnoid space, and spinal cord in the cervical canal. RESULTS: The clinical study of C3-C4 ACDF patients showed that as for the C3-C4 area, the area of the cervical vertebral canal, the area of the subarachnoid space, and he transverse surface area of the spinal cord were all significantly smaller in C3-C4 ACDF patients than in C5-C6 ACDF patients. Moreover, as for the C5-C6 area, only the area of the subarachnoid space was significantly smaller in C5-C6 ACDF patients than in C3-C4 ACDF patients. Spondylotic changes predominated at both the C3-C4 and C5-C6 levels. However, in the C5-C6 ACDF patients, spondylotic changes tended to predominate only at the operation level at C5-C6. CONCLUSIONS: Aging process develops from lower cervical to upper cervical level. Moreover, this static factor in conjunction with dynamic factor (instability) was the causative factors for the CSM in C3-C4 ACDF patients.

Clinical study of C3-C4 level surgical cases of cervical spondylosis.

OBJECTIVE: The purpose of this study was to elucidate the pathological characteristics of C3-C4 cervical spondylotic myelopathy (CSM). METHODS: Single-level anterior cervical discectomy and fusion (ACDF) was performed at C3-C4 in 53 patients (38 men, 15 women). The mean duration of preoperative symptoms was 6.0 months. Fifty-three non C3-C4 ACDF patients of our random sample of ACDF patients were compared to the C3-C4 ACDF patients. Clinical outcomes were assessed according to the Japanese Orthopedic Association score (JOA score), the Neurosurgical Cervical Spine Scale (NCSS), and the Nurick scale. And radiological findings including C2-C7 lordosis, C3-C4 range of intervertebral motion (ROM), C2-C7 ROM, and C3-C4%ROM in the cervical spine were evaluated in both groups. RESULTS: The recovery rates of JOA score and the NCSS in C3-C4 ACDF patients were 62.5% and 62.1%, respectively. The radiological study of C3-C4 ACDF patients showed that they had significant cervical lordosis, and cervical motion was dependent on the C3-C4 segment, which accounted for 39.8% of C2-C7 ROM (total motion). CONCLUSION: In C3-C4 ACDF patients, not only static factors, but dynamic factors (instability) at the C3-C4 level contributed to the major causes of CSM.

Identification of the 5,5-dioxo-7,8-dihydro-6H-thiopyrano[3,2-d]pyrimidine derivatives as highly selective PDE4B inhibitors.

A PDE4B subtype selective inhibitor is expected to have a wider therapeutic window than non-selective PDE4 inhibitors. In this Letter, two series of 7,8-dihydro-6H-thiopyrano[3,2-d]pyrimidine derivatives and 5,5-dioxo-7,8-dihydro-6H-thiopyrano[3,2-d]pyrimidine derivatives were evaluated for their PDE4B subtype selectivity using human PDE4B2 and PDE4D2 full length enzymes. To improve their PDE4B selectivity over PDE4D, we optimized the substituents on the pyrimidine ring and the side chain phenyl ring, resulting in several derivatives with more than 100-fold selectivity for PDE4B. Consequently, we identified 2-(3-chloro-4-methoxy-phenyl)-5,5-dioxo-7,8-dihydro-6H-thiopyrano[3,2-d]pyrimidine derivative 54 as a highly selective PDE4B inhibitor, which had potent hPDE4B inhibitory activity with an IC50 value of 3.0 nM and 433-fold PDE4B selectivity over PDE4D.

Surgical consideration of cervical dumbbell tumors.

BACKGROUND: Nineteen patients with cervical dumbbell tumors treated surgically were analyzed retrospectively. METHODS: Surgical strategies for dumbbell tumor were discussed from the perspective of safe, less-invasive surgery. RESULTS: Patients included 6 men and 13 women, with a mean age at the time of surgery of 48.3 years (range, 25-70 years). Underlying pathologies included 16 schwannomas, 2 neurofibromas, and 1 double tumor (schwannoma and meningioma). According to Eden's classification, one patient was classified as Type 1, 5 as Type 2, 8 as Type 3, and 5 as Type 4. In 13 cases, tumors were excised through the posterior approach alone, compared to five cases using the anterior approach. One case was excised using combined anterior and posterior approaches. Facetectomy was not performed in 18 cases. In one case, the facet joint on one side had already destroyed and needed instrumentation. Tumors were totally excised in all cases. Postoperatively, the patients did not display any further neurological deficit, with the exception of transient radiculopathy in two patients. Major surgical complications and cerebrospinal fluid leakage were not seen. Tumor recurrence and spinal segmental instability were not found during follow-up period (mean, 41.6 months). CONCLUSIONS: Dumbbell tumor surgery requires sufficient debulking of the epidural and paravertebral mass, using intraoperative nerve stimulation and Doppler ultrasonography to detect the vertebral artery. When using a posterior approach, recapping laminoplasty using an ultrasonic bone curette is very useful to remove tumor without sacrificing facet joints.

Thoracolumbar extradural arachnoid cyst--three surgical case reports.

Three cases of symptomatic extradural arachnoid cyst were treated by surgery. Total excision of the cyst followed by tight closure of the fistula by suture was achieved in all 3 cases. Surgery improved the neurological deficits but urinary incontinence persisted in all three patients. Obliteration of the fistula is considered to be important at surgery from the etiological perspective of the cyst. There are many surgical options, but surgical removal of the cyst and obliteration of the communication usually leads to prompt improvement in neurological deficits. Instability, malalignment, and worsening scoliosis are well-recognized postoperative complications of excessive laminotomy, but the exposure should be wide enough to cover the cyst completely at the operation. Wide exposure of the entire cyst is preferable to avoid missing the fistula and to identify any adhesions or fistula between the cyst and the dura. Identification of the fistula location based on preoperative imaging studies is also important.

Recapping hemilaminoplasty for spinal surgical disorders using ultrasonic bone curette.

OBJECTIVE: The authors present a novel method of the recapping hemilaminoplasty in a retrospective study of patients with spinal surgical disorders. This report describes the surgical technique and the results of hemilaminoplasty using an ultrasonic bone curette. The aim of this study was to examine the safety and effectiveness of the hemilaminoplasty technique with ultrasonic bone curette. METHODS: Between April 2003 and July 2011, 33 patients with various spinal diseases (17 spinal tumors, 5 dural arteriovenous fistulas, 3 syringomyelia, 2 sacral perineural cysts, and 2 arachnoid cysts) were treated microsurgically by using an ultrasonic bone curette with scalpel blade and lightweight handpiece. The ultrasonic bone curette was used for division of lamina. After resection of the lesion, the excised lamina was replaced exactly in situ to its original anatomic position with a titanium plate and screw. Additional fusion technique was not required and the device was easy to handle. All patients were observed both neurologically and radiologically by dynamic plain radiographs and computed tomography (CT) scan. RESULTS: The operation was performed successfully and there were no instrument-related complications such as dural laceration, nerve root injury, and vessels injury. The mean number of resected and restored lamina was 1.7. CT confirmed primary bone fusion in all patients by 12 months after surgery. CONCLUSION: The ultrasonic bone curette is a useful instrument for recapping hemilaminoplasty in various spinal surgeries. This method allows anatomical reconstruction of the excised bone to preserve the posterior surrounding tissues.

Strength testing of the human olfactory nerve at the frontal skull base.

Olfactory dysfunction may influence the quality of life tremendously. This study investigated the strength of the human olfactory nerve at the frontal skull base using cadavers. A total of 180 olfactory nerves were examined in 90 human cadaveric heads. The cut edges of the olfactory nerves were pulled until they were pulled out from the skull base. In the first set of 30 cases, each right olfactory nerve was pulled 0° laterally and 0° upward, and each left olfactory nerve was pulled 0° laterally and 15° upward. In the second set of 30 cases, each right olfactory nerve was pulled 0° laterally and 15° upward, and each left olfactory nerve was pulled 15° laterally and 15° upward. In the third set of 30 cases, each right olfactory nerve was pulled 15° laterally and 15° upward, and each left olfactory nerve was pulled 30° laterally and 15° upward. The strength of the olfactory nerve was measured when pulled in each direction. There was no significant difference in the strength of the olfactory nerves when pulling them in the postero-upward direction between 0° and 15° upward. The strengths of the olfactory nerves when pulling them in the postero-lateral direction 0° and 15° laterally were 3.14±1.87 and 4.05±1.70 g (mean ± standard deviation [SD]), respectively; the difference was almost significant. The olfactory nerve could be pulled more laterally than posteriorly because the retraction force is absorbed by the lateral wall of the olfactory fossa.

[Concomitant intracerebral hemorrhage and cerebral infarction in moyamoya disease: a case report].

We encountered a case of moyamoya disease which exhibited intracerebral hemorrhage with intraventricular hemorrhage followed by cerebral infarction in a short time. A 39-year-old female presenting with sudden onset disturbance of consciousness was admitted to our hospital. Radiological investigation on admission revealed intracerebral hemorrhage in the left temporal lobe and intraventricular hemorrhage due to moyamoya disease. The patient experienced cerebral infarction of the left frontotemporal area with brain swelling after 20 hours had passed. In spite of immediate left frontotemporal craniectomy and evacuation of the hematoma, she died 9 days after the operation. This case indicates that adequate control of intracranial pressure such as ventricular drainage is important to prevent progression of ischemic attack at an early stage. But it is not known what case of cerebral hemorrhage due to moyamoya disease would be complicated by cerebral infarction. The detection of the patient's consciousness level at an early stage could be a landmark to prevent further ischemic complications.

Minimally invasive central corpectomy for ossified posterior longitudinal ligament in the cervical spine.

Minimally invasive central corpectomy (MICC) for cervical segmental ossified posterior longitudinal ligament (OPLL) is described. The procedure of MICC includes upper- or lower-half central corpectomy of the involved cervical spine, transdiscal decompression of the adjacent disc level, dissection and partial removal of the OPLL, removal of the OPLL behind the vertebral body via these windows, and fusion with cylindrical titanium cages. Anterior plate fixation is not necessary. From January 2008 to December 2009 we surgically treated three patients with cervical OPLL by MICC. All three patients showed remarkable improvement of their symptoms within a few days after the operation. No neurological or radiological complication was observed during that period. MICC is beneficial in avoiding complete corpectomy and long fusion, usage of an anterior plate, and usage of a large external orthosis. MICC also reduces the risk of postoperative esophageal perforation due to a screw backing out of the plate.

[Postoperative patterns of improvement of symptoms and degrees of satisfaction in families of patients after operations for definite idiopathic normal pressure hydrocephalus: a long-term follow-up study].

PURPOSE: To clarify the patterns of improvement of pre- and post-operative symptoms and family satisfaction in patients with definite idiopathic normal pressure hydrocephalus (iNPN) who responded well to shunt intervention. SUBJECTS AND METHODS: The subjects included 40 patients definitively diagnosed with iNPH and who were followed up for one year or longer (age, 61-85; male-to-female ratio, 18: 22). The study focused on (1) preoperative clinical symptoms, (2) improvements in symptoms at 1, 3, 5, and 12 months after surgery, and the satisfaction of the families based on medical results of the Zarit caregiver burden interview, and infomation through questionnaires to medical personnel. RESULTS: (1) The major symptoms were gait disturbance (G, n=38), dementia (D, n=10), and urinary incontinence (U, n=23). G and D appeared as initial symptoms in 30 and 10 cases, respectively. (2) The rates of postoperative improvement at 1, 3, 5, and 12 months were 94.7%, 94.7%, 97.4%, and 94.7% for G, 43.8%, 62.5%, 71.9%, and 84.4% for D, and 78.3%, 86.96%, 86.96%, and 91.3% for U, respectively. G and U cases improved during the postoperative early stage, and D improved gradually from after the third postoperative month. The family satisfaction before surgery and at 1, 3, 5, and 12 months after surgery was 72.5 +/- 12.8, 68.1 +/- 15.4, 55.7 +/- 9.6, 52.9 +/- 11.4, and 47.3 +/- 7.9 points, respectively. The rate of improvement in satisfaction was higher for D. The satisfaction of the medical personnel was 88 percent (+) at 1 month and tended to remain high for 12 months. CONCLUSION: (1) Preoperative gait disturbance is a major initial symptom in definitively diagnosed iNPN. (2) Postoperative improvement of G and U is obtained at an early stage. In contrast, D tends to improve gradually from after the third postoperative month. The family satisfaction increases as the symptom of D improve. The satisfaction of the medical personnel tends to remain high after the first postoperative month. This study investigated the results of quantitative analyses of the patients symptoms.

Pathophysiology of cerebral circulatory disorders in idiopathic normal pressure hydrocephalus.

This study was conducted to elucidate the pathologic conditions of cerebral circulatory disorders in idiopathic normal pressure hydrocephalus (iNPH). Among 44 possible iNPH patients, 40 patients underwent shunt surgery based on diagnostic flow charts plotted by the Southern Tohoku method and were evaluated to be shunt-effective at the end of the first post-surgical month. The cerebral blood flow (CBF) was measured by N-isopropyl-((123)I)-P-iodo-amphetamine single photon emission computed tomography (mean, mCBF; cortical region, cCBF; thalamus-basal ganglia region, tbCBF on autoradiography [ARG] method) and the perfusion patterns of the cerebral cortex were measured based on three-dimensional stereotactic surface projection (3D-SSP) Z-score images, before and 1 month after the surgery in all 40 subjects. The mCBF rose significantly from 32.1 +/- 2.74 ml/100 g/min before surgery to 39.8 +/- 3.02 ml/100 g/min after surgery (p < 0.03). Investigation of the change of CBF revealed reductions in the cCBF (3 cases), tbCBF (9 cases), and cCBF + tbCBF (28 cases), with the reduced-cCBF group totaling 31 cases and the reduced-tbCBF group totaling 37 cases. Investigation of cerebral cortex hypoperfusion by 3D-SSP Z-score revealed 31 cases with hypoperfusion (frontal lobe type [19 cases], occipitotemporal lobe type [5 cases], mixed type [7 cases]) and nine cases with cortical normoperfusion (N). The pattern of reduction of the cortical blood flow on ARG method was favorably correlated with the pattern of hypoperfusion of the cerebral cortex on 3D-SSP Z-score images before surgery. A reduction of blood flow was found in the thalamus-basal ganglia region of all N type cases. The blood flow improved in 19 of 31 (61.3%) cases of the reduced-cCBF group and in 32 of 37 (86.5%) cases of the reduced-tbCBF group. All of the cases without detectable improvement exhibited increased blood flow in non-reduction areas. Investigation of the hypoperfusion patterns of the cerebral cortex on 3D-SSP Z-score images, revealed a reduction or disappearance of the hypoperfusion site in 19 of 31 (61.3%) cases, either no-change or a shift of the hypoperfusion site in 12 of 31 (38.7%) cases, and a correlation between the pattern of cortical blood flow reduction on ARG method and the pattern of cerebral cortex hypoperfusion on 3D-SSP Z-score images after surgery. Cerebral circulatory disorders in iNPH manifest as either of two pathophysiological conditions: the "circulatory disorder of the cerebral cortical region" and the "circulatory disorder of the thalamus-basal ganglia region." Various patterns develop according to the disease stage.

Intramolecular arene hydroxylation versus intermolecular olefin epoxidation by (mu-eta2:eta2-peroxo)dicopper(II) complex supported by dinucleating ligand.

A discrete (mu-eta2:eta2-peroxo)Cu(II)2 complex, [Cu2(O2)(H-L)]2+, is capable of performing not only intramolecular hydroxylation of a m-xylyl linker of a dinucleating ligand but also intermolecular epoxidation of styrene via electrophilic reaction to the C=C bond and hydroxylation of THF by H-atom abstraction.

Microscopic measurement of the facial nerve root exit zone from central glial myelin to peripheral Schwann cell myelin.

OBJECT: The authors have attempted to define the exact borders of the root exit zone (RExZ) of the facial nerve, measure the distribution of myelin histologically, and examine the relationship between contact vessels and the RExZ. METHODS: Seventy-five facial nerves were obtained from brainstems excised from 44 adult patients at autopsy. The arteries and veins associated with the facial nerve were counted and measured. The facial nerves, associated vasculature, and adjoining portions of the brainstem were then removed en bloc. These tissues were serially sectioned and stained, and a photomicrograph of each section was obtained. The distribution of myelin on each section was measured from the upper edge of the supraolivary fossette, and the relationship between contact vessels and the RExZ examined. The lateral transitional zone of the facial nerve began 8 mm distal to the upper edge of the supraolivary fossette (root exit point [RExP]) and had a mean length of 1.9 mm. The root detachment point (RDP) of the facial nerve at the medial side was located very close to the beginning of the medial transitional zone. In more than 80% of the nerves that were examined, vascular structures compressed the central glial myelin of the nerve. CONCLUSIONS: The authors propose the use of the terms "RExP," "RDP," and "transitional zone," instead of RExZ, which cannot be well defined. The RDP appears to be a good landmark for use during microvascular decompression.