Clinical and Radiologic Assessment for Anterior Cervical Interbody Fusion with Synthetic Cages

OBJECTIVE: This purpose of this study was to determine the clinical efficiency and applicability, and to analyze the radiologic findings of the anterior cervical approach using two synthetic cages for interbody fusion. METHODS: A total of 41 patients with cervical diseases underwent anterior discectomy and interbody fusion with the PEEK Solis(TM) cage in 21 patients and the carbon composite Osta-Pek(TM) cage in 20 patients. Outcome assessment was done using Odom's criteria. Radiological assessment was performed with respect to subsidence, bony fusion and lordosis. The mean follow-up period was 13 months. RESULTS: There were 34 (92.9%) successful cases. The average height of the disc space 12 months after surgery compared to the height before surgery was increased in 28 cases. The height of the disc space 12 months after surgery compared to the height just after surgery was decreased over 3mm in 4 cases, indicating severe subsidence. The use of these synthetic cages have provided the increase in postoperative cervical lordosis. CONCLUSION: There were no significant differences between the Solis(TM) and Osta-Pek(TM) cages on clinical and radiologic outcomes. Both Solis(TM) and Osta-Pek(TM) cages showed low subsidences and complications associated with hardware with good clinical outcomes, high fusion rates, restored disc heights, and restored cervical lordosis.

Retroperitoneal Hematoma Secondary to Terminal Branch of Segmental Artery Injury during Intertransverse Discectomy through Paramedian Muscle Splitting Approach

A 47-year-old man underwent the surgery of intertransverse discectomy through paramedian muscle splitting due to extraforaminal type of far lateral disc herniation at 4th-5th interspace of lumbar vertebrae. The authors encountered the terminal branch of the segmental artery that traversed the extruded disc around the dorsal root ganglion during the sugery. We coagulated the artery by a bipolar coagulator and cut the artery for the discectomy. There was no active bleeding during the surgery. However, the patient suffered from abdominal, right leg and flank pain at the first postoperative day. The follow-up magnetic resonance imaging revealed a retroperitoneal hematoma at the operation site. The patient underwent removal of the retroperitoneal hematoma. We identified the cause of bleeding as the rupture of coagulated terminal branch of the segmental artery around the dorsal root ganglion. The retroperitoneal hematoma was evacuated completely. The ruptured artery was clipped by a small metal clip, and his symptoms subsequently were resolved.

Chronic Spinal Epidural Abscess after Epidural Analgesia: Case Report

Three cases of chronic spinal epidural abscess following spinal epidural analgesia are presented. Spinal epidural abscess is a relatively rare infectious disease. It has recently increased in frequency due to the increased use of epidural steroid injections and epidural analgesia. It is very difficult to detect the spinal epidural abscess from its variable symptoms. So, it is important in making a diagnosis of epidural abscess to take into account the previous history of epidural analgesia.

Clinical Comparison between Microsurgical Decompression and Lumbar Interbody Fusion with Instrumentation for Lumbar Stenosis

OBJECTIVE: We report clinical results of the patients who received microsurgical decompression procedure(bilateral partial laminectomy and medial facetectomy: Group A) compared with lumbar interbody fusion with instrumentation(total laminectomy, interbody fusion and pedicle screw fixation: Group B). METHODS: From March 1996 to December 2000, twenty patients with symptomatic lumbar stenosis underwent microsurgical decompression and twenty-five patients underwent lumbar interbody fusion by two operators. Two groups of patients were compared retrospectively in respect to the mechanical back pain, leg pain, motor weakness, sensory hypesthesia(numbness) and clinical outcomes. The mean follow-up period was 30 months. RESULTS: In Group A, mechanical back pain, leg pain, motor weakness, and sensory hypesthesia were improved in 72.2%, 69%, 80%, 44.4% and 70%, 71%, 83.3%, 50% respectively in Group B. Clinical outcomes was excellent or good in 80% in Group A and 84% in Group B and no differences in clinical parameters between Groups were demonstrated. CONCLUSION: We recommend microsurgical decompression for the patients suffering from symptomatic lumbar stenosis with stable spine because microsurgical decompression provided a satisfactory clinical results equivalent to lumbar interbody fusion with instrumentation.

Results of Microsurgical Anterolateral Tunnel Approach for Cervical Disc Herniation

OBJECTIVE: The authors report the microsurgical anterolateral tunnel approach for the treatment of the cervical disc diseases and its postoperative surgical results. METHODS: All surgical procedures followed the method of classical microsurgical anterior discectomy. Small tunnel(7-8mm) was made on the disc space reaching to the posterior longitudinal ligament. The disc materials and bony spurs were removed through this tunnel. Thirty-one patients of cervical disc herniation(24 cases with pure disc herniation, 7 cases with combined cervical spondylosis) were evaluated on the symptoms, conformation in plain X-ray, C-T, and MRI. The follow up time was over 2 years . RESULTS: Postoperatively the result(following the out come scale) was excellent and good in Twenty-nine patients. One with fair result showed remnant disc particle and spur and another one is combined with cord contusion. One patient with lesion in C 3-4 space and two cervicothoracic junction showed excellent result. Two patients with osteoporosis also showed good results. Cervical spine curvature and disc space height were not changed on the plain X-ray and MRI in all patients. Twenty-nine patients were discharged within 3 days after surgery without any postoperative complications. CONCLUSIONS: The microsurgical anterolateral tunnel approach could be indicated for the treatment of patients with cervical disc diseases and with difficulty in achieving interbody fusion(the higher cervical level and cervicothoracic junction, osteoporosis etc.).

Extradural Thoracic Spinal Meningioma Arising from a Nerve Root

Extradural meningiomas are relatively rare and those arising from spinal root are even rarer. Recently, a case of extradural meningioma arising from a spinal nerve root was surgically treated in our institution. This patient was a 19-year-old female presented with paraparesis and paresthesia. The mass was compressing the spinal cord at the level of fourth thoracic spine, and it was extended to the nerve root. At operation it was found to be originated from the fourth thoracic spinal nerve root. After removal of the tumor, the neurologic symptom and sign were recovered completely. Histoligic examination of tumor revealed as transitional type of meningioma.

Brain Language Network and Lateralization Using for Spoken and Written Korean Words in Normal Adults: A Functional MRI Study

OBJECTIVE: This study involves an experiment using functional magnetic resonance imaging (fMRI) to delineate neural network and laterality of language related brain activation for spoken and written Korean words in normal adults. METHOD: Eight normal right-handed Korean males, aged 20~33 years, were investigated. Language tasks consisted of auditory and visual verb generation tasks. In fMRI, twenty slices were obtained for each functional volume using single shot echoplanar image sequences. Data were motion corrected, coregistered, normalized, and statistically analyzed using SPM-96 software. The number of activated voxels were counted in each hemisphere to calculate the laterality index according to each language task. RESULTS: In auditory verb generation task, inferior frontal gyrus and superior temporal region were activated in the left side. Right temporal lobe was also activated in the superior and middle temporal areas. Other activated area included medial frontal lobe. Lateralization index of auditory verb generation task was +78.6 +/-30.7. In visual verb generation task, inferior frontal gyrus was activated in the left side. Medial frontal lobe, both lateral occipital lobe, and left parietal lobe were also activated. The laterality index was +87.6 +/- 10.1. CONCLUSION: We could delineate cortical regions subserved for spoken and written Korean language and laterality of language related brain activation using fMRI. These results can contribute to understand underlying mechanism of language disorders in brain injury patients and to investigate the pattern of reorganization of language network after rehabilitation.

Follow-up Results of Z-plate Fixation in the Thoracolumbar Burst Fracture

No abstract available.

Surgical Management of MRI-invisible Extratemporal Epilepsy

OBJECTIVE: The advent of high resolution magnetic resonance imaging(MRI) contributed to the preoperative localization of epileptogenic area. Even the discrete lesion visualized on MRI can be often correlated with seizure onset zone. If MRI does not, however, show any lesions in the extratemporal epilepsy, it imposes a significant challenge. This study is designed to evaluate the surgical treatment of extratemporal lobe epilepsy in which MRI does not show any lesion, to define the surgical strategy and to investigate the underlying pathology. METHODS: We studied the nineteen patients with MRI-negative extratemporal epilepsy who underwent resective surgery after careful preoperative investigation between 1993 and 1995. RESULTS: Scalp EEG could not lateralize the epileptogenic foci in 9 patients. Intracranial EEG recording was performed in all patients with successful localization: depth electrode study in 12, and subdural grid and strip study in 7 patients. Resection was performed in frontal(n=14), in parietal(n=3), and in multilobar area(n=2). Pathological findings comprised cortical dysplasia in 10, gliosis in 7, and collagenoma in one patients. The surgical outcome was classified as seizure free in 10, rare seizures in 2, significant reduction in 5, and no change in 2 patients. CONCLUSION: MRI-invisible extratemporal epilepsy can be managed surgically with promising results. Cortical dysplasia and gliosis are two major pathological findings in this context though MRI does not demonstrate any lesions.

Removal of Cervical Dumbbell Schwannoma in a Single Stage by Posterior Approach

Single staged posterior approach was carried out for three patients of dumbbell shaped schwannomas at the cervical region. Gross total resection was achieved in all of the patients, using a modified posterior midline exposure with hemilaminectomy and complete unilateral facetectorny. This exposure provided contiguous intraspinal, foraminal and extraforaminal access delete up to 2-3cm from lateral dural margin. The vertebral artery could be safely preserved from tumor mass. Although the follow up period is short, three patients showed no postoperative cervical spinalies from these operation. Illustrations of this approach with its possible application is discussed.

Isthmic Spondylolisthesis with Sciatica: Follow-up Results after Posterior Lumbar Interbody Fusion and Transpedicular Screw Fixation

The main symptoms of adult isthmic spondylolisthesis are frequently low back pain and radicular leg pain. Laminectomy and posterolateral fusion is somtimes unsuccessful because nerve roots are compressed by fibrocartilagenous tissue at pars defect, degenerated disc and slipped bony edge. The patients need complete neural decompression, reduction of slipping and stable fixation. We have operated 22 patients with PLIF using carbon cage and transpedicular screw fixation after posterior decompression by Gill's operation and complete removal of intervertebral disc. We studied the patients postoperatively to evaluate the symptomatic improvement, reduction rate of slipping and stability of lumbar spine. Twenty-two patients were operated from April, 1996 to June, 1997. Mean age was 46, ranging from 35 to 68. Mean follow-up duration was thirteen months. The levels of operarion were 9 at L4-5 and 9 at L5-S1, 4 at both levels. Mean preoprative slip was 17.2%, which was reduced to 11.3% postoperatively. Nineteen patients(86%) were satisfied with the result of operation. The fusion rate of PLIF was 86%. There was no breakage of instrumentation or postoperative instability. We consider that PLIF and transpedicular screw fixation for adult isthmic spondylolisthesis with radicular leg pain is a good methods to obtain complete neural decompression, reduction of slip and stable lumbar fixation.

Polymorphism of Angiotensin Converting Enzyme in Hypertensive Intracerebral Hemorrhage Patients

Polymorphism in the angiotensin-converting enzyme(ACE) gene may confer an increased risk of vascular disease. DD type of ACE polymorphism predispose a person to myocardial infarction and IgA nephropathy. The roles of the ACE insertion/deletion polymorphism are unknown in the patients with hypertensive intracerebral hemorrhage (HICH). Our objective is to test and to identify whether genotype distribution of the insertion/deletion polymorphism in ACE gene is different in HICH patients from control subjects. Fifty six HICH patients and sixty one control subjects were studied. Genotypes were determined by the polymerase chain reaction(PCR) with specific oligonucleotide primers flanking the polymorphic region in intron 16 of ACE gene to amplify genomic DNA isolated from patients blood PCR products were separated in 2% agarose gels and bands were visualized by ethidium bromide staining. The PCR reaction amplified a 490bp DNA fragment(II type) from genomic DNA if the subjects had an intact intron 16, and amplified a both 490bp and 190bp DNA fragments(ID type) if subjects had heterozygous polymorphism. While the distribution of ACE polymorphism in control subjects was 26.2%:57.4%:6.4%(II:ID:DD), and the distribution of it in patients with HICH was 37.5%:35.7%:26.8%. Thus, the pattern of distribution was no significant different between control subjects and patients with HICH. The factors of age and sex did not influence on the ratio of distribution in both control and HICH subjects. From these results, we conclude that there is no significant association between I/D polymorphism and HICH.

Strategies for Anterior Screw Fixation for Type II Odontoid Process Fracture, and Long-Term Follow-up Results

Type II fracture of the odontoid process is the most common form of axis fracture, and because of the difficulty in healing, its results may be fatal. The authors subclassified these fractures as anteriorly displaced(type II-A), posteriorly displaced(type II-P), and non displaced(type II-N). Twelve patients with type II fractures underwent anterior screw fixation : three were type II-A : one, type II-P : and eight, type II-N. The mean duration of follow-up was 29.3 months, and all patients except two showed good alignment and stable fixation : these exceptions were type II-A, with 9mm displacement, and showed delayed failure of screw fixation. All type II-N, II-P, and II-A, with 3mm displacement, were successfully treated. We conclude that selection of the treatment modality should be based on the direction of displacement of odontoid process. For type II-N, II-P and II-A fractures, where displacement is mild, anterior screw fixation is a reliable method, but for type II-A fracture, with severe displacement, posterior fixation should be considered.

Surgical Treatment of Postencephalitic Epilepsy

Encephalitis is often followed by chronic intractable epilepsy. Many of these patients pose significant challenges to the localization of seizure generators and to the strateges for management of intractable epilepsy. The authors analysed 17 patients with postencephalitic epilepsy(PEE), who underwent resective surgeries. Most patients had been accompanied by coma, convulsive status epilepticus, and focal motor deficit at the time of encephalitis. MRI studies showed variable degree of brain damage: hippocampal sclerosis only(n=5), neocortical gliosis only(n=6), and both(n=5). Analysis of ictal semiology revealed a predominant temporo-limbic seizure pattern in 7, a variable extralimbic patterns in 6, and unclassified in 4 patients. Surgical resection includes temporal(n=11), frontal(n=3), centroparietal(n=1), multilobar(n=2), and callosotomy(n=2). Surgical outcome was graded as class 1(n=8), class 2(n=2), class 3(n=4), and class 4(n=3). It is concluded that surgical result was promising despite the traditional concerns about localizing problem in the setting of PEE. Surgical treatment should be, therefore, considered if localizing information is persistent. Intracranial EEG recording was very useful to delineate the area of seizure onset. MRI abnormalities were not always correlated with ictal onset zone in the patients with PEE.

Chondroma on Lamina of C1 Associated with Symptom of Spinal Cord Compression

Chondroma is a benign bone tumor and rarely involves the spine ; even if this occurs however, neurological symptoms and signs rarely arise. We encountered one case of chondroma which developed in the posterior arch of the atlas. The patient complained of quadriparesis, hypesthesia, and urinary frequency. MR imaging showed that the tumor had compressed the cord dorsolaterally at the C1 level. It was completely removed, and the posterior arch of the atlas and surrounding ligamentum flavum disclosed hypertrophy. Postoperatively, the neurological status of the patient improved. On pathologic examination, hypocellularity and mature hyaline cartilage was seen, as well as chondrocytes residing in the lacunae ; all these findings were compatible with benign chondroma.

Surgical Treatment of Intractable Frontal Lobe Epilepsy

Recent advances of neuroimaging and electrophysiological monitoring technique have contributed in improving the surgical outcome of frontal lobe epilepsy. The authors have analysed 36 consecutive cases of intractable frontal lobe epilepsy that were treated at our institute between September, 1992 and December, 1995 to determine the clinical, electrophysiological, and neuroimaging characteristics as well as to delineate the efficacy of surgical treatment in improving the seizure outcome. The patients consisted of 19 males and 17 females. The mean age of the seizure onset and the mean duration of epilepsy were 14.9 and 11.6 years, respectively. Magnetic resonance imaging(MRI) showed no lesion in 9 patients and pathological lesions in 27 patients. The types of the lesions observed included primary brain tumor, mostly low-grade glioma in 10 patients, cortical dysplasia in 4, post-traumatic scar in 4, neocortical gliosis in 3, cyst in 3, and postencephalitic atrophy in 3. Intracranial recordings were performed in 23 cases to determine the epileptogenic zone. The surgical outcome was graded according to Engle's Classification as Class A in 20 patients, Class B in 2, Class C in 9, and Class D in 5. The surgical outcome was promising regardless of the presence or the absence of the lesion on MRI, invasive recording, age of seizure onset, and duration of epilepsy.

Clinical Results of Internal Fixation Using Several Instruments in Unstable Thoracolumbar Bursting Fracture

Fifty six patients with unstable thoracolumbar bursting fractures were treated using variable internal fixation devices such as the Kaneda Anterior Fixation System(Kaneda device), the Z-Plate-ATL(TM) Anterior Fixation System(Z-Plate ATL(TM) device), the Harrington device, Cotrel-Ducousset(CD) or Compact Contrel Dubousset(CCD) device or Steffee Transpedicular System with or without decompression. Such internal fixation devices were grouped into anterior and posterior internal fixation devices and compared with each other in the aspect of the degree of neurological improvement, the changes of the vertebral height and the kyphotic angle, the duration of admission, and postoperative complications. In conclusion, the anterior internal fixation device appears to be of more benefit in the management of patients with unstable thoracolumbar bursting fracture.

Results of Anterior Cervical Discectomy without Interbody Fusion

Anterior cervical discectomy with or without interbody fusion has been conventionally used to treat patients with cervical disc diseases. However, discectomy without bone fusion has been abandoned due to the feat of early collapse of interbody space and recurrency. The author has analysed twenty-two cases of microsurgical cervical discectomy without bone fusion between Jan. 1993 and Mar. 1994. All patients were followed up for more than 6 months or as long as 21 months with repeat interview, physical examination, and radiological evaluation. The analysis revealed that the results were highly satisfactory in 21 cases with radiculopathies in terms of early ambulation, no discomfort in the iliac bone, and shorter hospital stay, but unsatisfactory in one cases which needed reoperation due to postoperative scar. The above method which had demonstrated promising results is recommended for the patients suffering from radiculopathy.

Congenital bilateral perisylvian syndrome: analysis of the first four reported Korean patients

The advent of MRI technique has enabled the diagnosis of neuronal migration disorders(NMD) and made it possible to make "in vivo" diagnosis. Congenital bilateral perisylvian syndrome(CBPS) is a recently described disease identify characterized by pseudobulbar palsy, epilepsy, mental retardation, and migration disorders in the bilateral perisylvian area. We have identified four CBPS patients based on neuroimaging and dysarthria patterns among the candidates for epilepsy surgery. All the patients had orofacial diplegia and variable degrees of mental retardation. In the spectrographic analysis of dysarthria, the loss of specific characteristics of formants of vowels and increment of noise in the high frequency formants were observed. Epilepsy was present in all, but only one patient showed intractable seizure requiring surgical intervention. MRI was most helpful in identifying NMD and polymicrogyria in both centroparietal areas in this context. Great alertness is needed to identify this disorder to determine the etiology of epilepsy and dysarthria of uncertain origin.

Rolandic Cortical Dysplasia: Case Report

The advent of MRI enables us to make an in-vivo diagnosis of cortical dysplastic lesions which are highly epileptogenic and show the variety of seizure patterns. Authors report a case of rolandic cortical dysplasia who had highly intractable focal motor clonic seizures. Invasive recording with subdural grid was very helpful in delinating the epileptogenic area as well as in function mapping of eloquent areas. Total removal of dysplastic lesion could treat this highly intractable epilepsy succesfully.