Young Sun Chung

Treatment of Intra- and Extracranial Arterial Dissections Using Stents and Embolization

PurposeTo evaluate the safety and efficacy of stent placement for extracranial and intracranial arterial dissections.MethodsEighteen patients underwent endovascular treatment of carotid and vertebral dissections using intraluminal stent placement. Five patients with arterial dissection were treated, 2 using one insertion of a single stent and 3 using placement of two stents. Patients with a dissecting aneurysm were treated as follows: 7 patients with insertion of one stent, 4 with placement of two stents, and 2 by stent-assisted Guglielmi detachable coil embolization. In the 18 patients in whom stenting was attempted, the overall success in reaching the target lesion was 94.4%. Of the 17 patients treated with stents, stent release and positioning were considered optimal in 16 (94%) and suboptimal in one (6%). In patients who underwent a successful procedure, all parent arteries were preserved. There were no instances of postprocedural ischemic attacks, new neurologic deficits, or new minor or major strokes prior to patient discharge. In follow up, all patients were assessed, using the modified Rankin scale, as functionally improved or of stable clinical status. The reduction in dissection-induced stenosis or pseudoaneurysm, the patency rate obtained at follow-up, and the lack of strokes (ischemic or hemorrhagic) suggest that stent placement offers a viable alternative to complex surgical bypass or reconstructive procedures. The long-term efficacy and durability of stent placement for arterial dissection remain to be determined in a larger series.

Stent-graft placement in a traumatic internal carotid-internal jugular fistula and pseudoaneurysm

Traumatic arteriovenous fistulas following carotid artery injuries are rare. Treatment of carotid artery-to-jugular vein fistula requires direct closure of the fistula or occlusion of the carotid artery above and below the level of the fistula, by a surgical or endovascular approach. A 32-year-old man presented with a right-sided pulsatile neck swelling 2 days following a stab wound. Neck computed tomography demonstrated a vascular mass protruding into the anterior neck. Digital subtraction arteriography demonstrated a bilobular large internal carotid artery pseudoaneurysm just distal to its bifurcation. There was simultaneous opacification of a dilated left internal jugular vein indicating a high-flow internal carotid-internal jugular fistula. A balloon-expandable stent-graft was delivered and successfully positioned across the fistula. The arteriovenous fistula and pseudoaneurysm completely disappeared and the right internal carotid artery was well preserved. The stent-graft is a promising technology to obliterate fistulae and preserve the parent artery with relative safety.

Therapeutic Effects of Holmium-166 Chitosan Complex in Rat Brain Tumor Model

This study examined the effectiveness of Holmium-166 (Ho-166) chitosan complex therapy for a malignant glioma. Cultured C6 glioma cells (100,000 in 5 µl) were injected into the caudate/putamen of 200 - 250 gram Wistar rats. Five days later, a Ho-166 chitosan complex was injected into the same site of the glioma injection. Four injection doses were administered: the control group received PBS 10 µl, group 1 received an injection of 100 µCi (10 µl), group 2 received an injection of 50 µCi (5 µl), and group 3 received an injection of 10 µCi (1 µl). The average tumor volume for each group was 1.385 mm3 for the control group, 0.036 mm3 for group 1, 0.104 mm3 for group 2, and 0.111 mm3 for group 3. Compared with the control group, the size of the tumors in groups 1, 2 and 3 was reduced by an average of 97.4%, 92.5% and 91.9%, respectively. The Kaplan-Meier survival curve of group 2 was the longest, followed by groups 3, group 1 and the control. The mean survival was 22.8, 59, 60, and 44.6 days for the control group and groups 3, 2 and 1, respectively. H-E staining revealed that group 2 yielded the best results in the destruction of the malignant glioma. TUNEL staining and immunohistochemical studies indicated apoptotic features. The Ho-166 chitosan complex proved to be effective in destroying the malignant glioma.

Significance of chronic epilepsy in glial tumors and correlation with surgical strategies

PURPOSE This study was designed to compare the frequency of postoperative epilepsy in patients with acute and chronic pre-operative epilepsy and with frontal or temporal lobe glial tumors based on the hypothesis that patients with chronic epilepsy do worse. METHODS We compared the clinical and diagnostic characteristics of the patients (n = 73) who had seizures preoperatively with those of the patients (n = 153) who did not. Among those who have had seizures preoperatively, we compared those (n = 32, chronic seizure group) who had seizures a year or more prior to surgery with those (n = 41, acute seizure group) who had seizures less than a year prior to surgery. RESULTS Among the various factors, the frequency of benign pathology and favorable neurological state were higher in the seizure group than in the non-seizure group (p < 0.05). Complex partial seizures and low-grade tumors were frequent in the chronic seizure group, whereas simple partial seizures and high-grade tumors were frequent in the acute seizure group. Seizure-free rate was significantly higher in the acute seizure group than in the chronic group (p < 0.05). Also, the difference of seizure control rate between surgical strategies was statistically significant (p < 0.05). CONCLUSION This study indicates that preoperative seizure duration and frequency have a close relationship with the frequency of postoperative epilepsy in patients with glial tumors. A longer duration may allow the formation of epileptogenic foci, leading to chronic epilepsy, and eventually have a negative effect on the prognosis of the patients. Factors including histopathological characteristics of the tumor, its location, seizure duration/frequency, and symptomatology should be taken into account when deciding on surgical strategies.

Isolated pineal region metastasis of small cell lung cancer

The pineal region is an unusual site for brain metastasis and most metastatic pineal lesions are asymptomatic. Rarely the symptoms of metastatic involvement of the pineal gland precede those of the primary tumor or other metastatic sites. An 83 year-old man presented with gait disturbance and limitation of upward gaze. Brain MRI showed homogeneous enhancement of a solitary mass in the pineal region with obstructive hydrocephalus. A stereotactic biopsy was performed, and small cell carcinoma was diagnosed. A systemic investigation for the primary lesion subsequently revealed small cell carcinoma of the lung. The patient was referred for radiotherapy and chemotherapy. Although rare, metastatic tumor should be considered in the differential diagnosis of pineal region tumors, particularly in elderly patients.

Association of vascular endothelial growth factor gene polymorphisms with osteoporotic vertebral compression fractures in postmenopausal women

Vascular endothelial growth factor (VEGF) is involved in bone formation through its role in angiogenesis. VEGF is also known to promote the healing of fractures. Thus, we determined whether or not VEGF −2578C>A, −1154G>A, −634G>C, and 936C>T polymorphisms and haplotypes are associated with osteoporotic vertebral compression fractures (OVCF) in postmenopausal Korean women. The study subjects consisted of 82 patients with osteoporotic vertebral compression fractures and 117 control postmenopausal Korean women. PCR-RFLP and real-time PCR were used to analyze the VEGF polymorphisms. Homocysteine levels were also measured to determine whether or not polymorphisms of the VEGFgene affect homocysteine/folate metabolism. The AA genotype of the −2578C>A polymorphism was significantly different between the stroke and control groups; no significant differences in the −1154G>A, −634G>C, and 936C>T genotype frequencies existed. However, the A-G-G-C haplotype had a tendency to be associated with OVCF in postmenopausal Korean women. Associations between the VEGF −2578C>A polymorphism and homocysteine levels were also noted. In summary, these results suggest that the VEGF −2578C>A polymorphisms and VEGF haplotypes may play an important role in the etiology of OVCF in postmenopausal Korean women.

Spinal Subarachnoid Hematoma as a Complication of an Intramuscular Stimulation : Case Report and a Review of Literatures

Intramuscular stimulation (IMS) is widely used to treat myofascial pain syndrome. IMS is a safe procedure but several complications have been described. To our knowledge, spinal subarachnoid hematoma has never been reported as a complication of an IMS. The authors have experienced a case of spinal subarachnoid hematoma occurring after an IMS, which was tentatively diagnosed as intracranial subarachnoid hemorrhage because of severe headache. Patient was successfully treated with surgery. Here, we report our case with a review of literature.

Erratum to: Methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TS) polymorphisms with osteoporotic vertebral compression fracture (OVCF) in postmenopausal Korean women

Hyperhomocysteinemia is associated with the risk of skeletal health problems, such as osteoporosis, low body mineral density, and fracture. 5, 10-Methylenetetrahydrofolate reductase (MTHFR) and thymidylate synthase (TS) are involved in homocysteine metabolism. We hypothesized that certain genetic polymorphisms of MTHFR and TS that cause altered enzyme activity may lead to hyperhomocysteinemia and affect bone metabolism. Therefore, we determined whether MTHFR 677C>T, MTHFR 1298A>C, TS enhancer region (TSER), and TS 3′-UTR 6 bp insertion/deletion polymorphisms are associated with osteoporotic vertebral compression fracture (OVCF) in postmenopausal Korean women. A total of 308 postmenopausal Korean women were enrolled as study subjects. Among them, 84 were patients with OVCF and 224 were controls. The polymorphisms were analysed by PCR-RFLP methods. Single mutations of MTHFR or TS were not associated with the occurrence of OVCF. However, the combined genotypes 2R3R+2R2R/0bp6bp+6bp6bp (TSER/TS 3′-UTR) and AC+CC/0bp6bp+6bp6bp (MTHFR 1298A>C/TS 3′-UTR) were associated with decreased risk for OVCF. 2R-0bp and 2R-6bp haplotype frequencies of TS were significantly different between the cases and controls. In the present study, the combined genotype of TSER/TS 3′-UTR and MTHFR 1298A>C/TS 3′-UTR was associated with a decreased risk for OVCF in postmenopausal Korean women. However, due to the several limitations of our study including the moderately small sample size, our findings should be considered with caution and further research is needed to draw more definitive conclusions.

Traumatic dissection of the internal maxillary artery associated with isolated glossopharyngeal nerve palsy: case report.

OBJECTIVE AND IMPORTANCE:Spontaneous or traumatic dissection of the internal carotid artery with resultant lower cranial nerve palsies is well documented. However, dissection of the external carotid artery with lower cranial palsies has not been reported previously. CLINICAL PRESENTATION:A 42-year-old man experienced an epidural hematoma as the result of a fall and underwent a craniotomy and hematoma removal. Subsequently, he developed dysgeusia and difficulty in swallowing. Brain magnetic resonance imaging showed a dilated linear structure, with isosignal intensity on T1-weighted images and hyperintense signal intensity on T2-weighted images. Strong enhancement was seen on postcontrast T1-weighted images, indicating a dissected internal maxillary artery. This was confirmed on selective angiography of the left common carotid artery. INTERVENTION:Guglielmi detachable coils were introduced into the false lumen of the dissected artery. Subsequently, 0.5 ml of glue mixed with Lipiodol (Lafayette Pharmacal, Lafayette, IN) was packed into the remnant of the false lumen. Repeat angiograms demonstrated complete occlusion of the dissected vessel. The patient’s postoperative course was uneventful, and the neurological deficits gradually improved. CONCLUSION:We describe the first reported case of internal maxillary artery dissection and pseudoaneurysm presenting with isolated glossopharyngeal nerve palsy. The association between cranial nerve palsy and dissection of the external carotid artery branch may be the result of a compressive mechanism, as suggested by its anatomic relationships, the characteristics of the dissection, and the good prognosis. Endovascular embolization of the external carotid artery dissection and pseudoaneurysm is suggested as an effective therapeutic method for improving or alleviating neurological deficits produced by mass effect.

Subacute Course of Common Iliac Arterial Laceration in Lumbar Disc Surgery

Vascular injuries in lumbar disc surgery are serious complications which may be overlooked due to a broad range of clinical manifestations. It is important to be aware of the perioperative implications of this rare occurrence to lower mortality risk. A 20-yr-old man with a right L4-5 lumbar disc protrusion was operated on routinely under a surgical microscope. A bloody surgical field was noted temporarily during a discectomy along with a decreased blood pressure. After fluid resuscitation with an ephedrine injection, the bleeding soon stopped spontaneously and his vital signs were stabilized. Fifty hours after the operation, the patient showed signs of hypovolemic hypotension with abdominal distension. The right femoral artery pulsation was absent on palpation. An enhanced CT angiography revealed a retroperitoneal hematoma and obstruction of the left common iliac artery. An urgent laparotomy was done to repair the injured vessel by excision and interposition of a graft. The patient had an uneventful recovery.The subacute course of deterioration might have been due to intermittent blood leakage from the lacerated common iliac artery, which was sealed spontaneously. It is very important to pay close attention to post-surgical clinical manifestations to avoid a potentially fatal outcome in lumbar disc surgery.