Hyuk Jai Choi

Clinical outcomes of pulsed radiofrequency neuromodulation for the treatment of occipital neuralgia.

Objective Occipital neuralgia is characterized by paroxysmal jabbing pain in the dermatomes of the greater or lesser occipital nerves caused by irritation of these nerves. Although several therapies have been reported, they have only temporary therapeutic effects. We report the results of pulsed radiofrequency treatment of the occipital nerve, which was used to treat occipital neuralgia. Methods Patients were diagnosed with occipital neuralgia according to the International Classification of Headache Disorders classification criteria. We performed pulsed radiofrequency neuromodulation when patients presented with clinical findings suggestive occipital neuralgia with positive diagnostic block of the occipital nerves with local anesthetics. Patients were analyzed according to age, duration of symptoms, surgical results, complications and recurrence. Pain was measured every month after the procedure using the visual analog and total pain indexes. Results From 2010, ten patients were included in the study. The mean age was 52 years (34-70 years). The mean follow-up period was 7.5 months (6-10 months). Mean Visual Analog Scale and mean total pain index scores declined by 6.1 units and 192.1 units, respectively, during the follow-up period. No complications were reported. Conclusion Pulsed radiofrequency neuromodulation of the occipital nerve is an effective treatment for occipital neuralgia. Further controlled prospective studies are necessary to evaluate the exact effects and long-term outcomes of this treatment method.

Long Term Outcomes of Gamma Knife Radiosurgery for Typical Trigeminal Neuralgia-Minimum 5-Year Follow-Up

Objective Gamma knife radiosurgery (GKRS) is the least invasive surgical option for patients with trigeminal neuralgia (TN). However, the indications and long term outcomes of GKRS are still controversial. Additionally, a series with uniform long-term follow-up data for all patients has been lacking. In the present study, the authors analyzed long-term outcomes in a series of patients with TN who underwent a single GKRS treatment followed by a minimum follow-up of 60 months. Methods From 1994 to 2009, 40 consecutive patients with typical, intractable TN received GKRS. Among these, 22 patients were followed for >60 months. The mean maximum radiation dose was 77.1 Gy (65.2-83.6 Gy), and the 4 mm collimator was used to target the radiation to the root entry zone. Results The mean age was 61.5 years (25-84 years). The mean follow-up period was 92.2 months (60-144 months). According to the pain intensity scale in the last follow-up, 6 cases were grades I-II (pain-free with or without medication; 27.3%) and 7 cases were grade IV-V (<50% pain relief with medication or no pain relief; 31.8%). There was 1 case (facial dysesthesia) with post-operative complications (4.54%). Conclusion The long-term results of GKRS for TN are not as satisfactory as those of microvascular decompression and other conventional modalities, but GKRS is a safe, effective and minimally invasive technique which might be considered a first-line therapy for a limited group of patients for whom a more invasive kind of treatment is unsuitable.

Pulsed radiofrequency neuromodulation treatment on the lateral femoral cutaneous nerve for the treatment of meralgia paresthetica.

We describe a rare case of pulsed radiofrequency treatment for pain relief associated with meralgia paresthetica. A 58-year-old female presented with pain in the left anterior lateral thigh. An imaging study revealed no acute lesions compared with a previous imaging study, and diagnosis of meralgia paresthetica was made. She received temporary pain relief with lateral femoral cutaneous nerve blocks twice. We performed pulsed radiofrequency treatment, and the pain declined to 25% of the maximal pain intensity. At 4 months after the procedure, the pain intensity did not aggravate without medication. Pulsed radiofrequency neuromodulation treatment on the lateral femoral cutaneous nerve may offer an effective, low risk treatment in patients with meralgia paresthetica who are refractory to conservative medical treatment.

Whiplash injury-induced atypical short-lasting unilateral neuralgiform headache with conjunctival injection and tearing syndrome treated by greater occipital nerve block.

Background:Short-lasting unilateral neuralgiform headache with conjunctival injection and tearing (SUNCT) syndrome is a rare type of trigeminal autonomic cephalalgia. SUNCT syndrome is typically idiopathic, and secondary SUNCT syndrome after indirect injury is very rare. We report a case of SUNCT syndrome manifested dramatically after a whiplash injury and treated by greater occipital nerve (GON) block. Case:A 62-year-old woman presented with headache associated with ipsilateral orbitofacial pain, lacrimination, and conjunctival injection after a car accident. Imaging study revealed no acute lesions. The symptoms were triggered and worsened by touch on the ipsilateral scalp and posterior neck region, and also by talking, swallowing, or chewing. We performed GON blocks for headache 3 times. The patient experienced pain relief after a GON block. Conclusions:Secondary SUNCT syndrome induced by whiplash injury is rare. Our case showed good outcome of SUNCT syndrome treated by GON.

Microvascular decompression for hemifacial spasm due to four offending vessels: a case report.

A 65-year-old woman presented with left facial involuntary movement and facial palsy for eight years. Brain magnetic resonance image (MRI) and magnetic resonance angiography (MRA) revealed multiple vascular compression of facial nerve root exit zone (REZ). Standard retromastoid suboccipital craniectomy and arachnoid dissection were performed. Right vertebral artery (VA), left VA, left anterior inferior cerebellar artery (AICA), and left posterior inferior cerebellar artery (PICA) compressed the facial nerve in that order. The offending vessels were dissected away from the facial nerve and transposed sequentially. Teflon was interposed between the arteries and the nerve. Electrophysiological monitoring showed disappearance of the abnormal hemifacial spasm response during the operation. The offending vessels were right VA, left VA, left AICA, and left PICA. Postoperatively, the patients involuntary movement was completely resolved. We report a rare case of hemifacial spasm caused by four offending vessels that was treated by microvascular decompression (MVD) with wide arachnoid dissection.

Correlation of optic nerve sheath diameter with directly measured intracranial pressure in Korean adults using bedside ultrasonography

Objectives The correlation of optic nerve sheath diameter (ONSD) as seen on ultrasonography (US) and directly measured intracranial pressure (ICP) has been well described. Nevertheless, differences in ethnicity and type of ICP monitor used are obstacles to the interpretation. Therefore, we investigated the direct correlation between ONSD and ventricular ICP and defined an optimal cut-off point for identifying increased ICP (IICP) in Korean adults with brain lesions. Methods This prospective study included patients who required an external ventricular drainage (EVD) catheter for ICP control. IICP was defined as an opening pressure over 20 mmHg. ONSD was measured using a 13 MHz US probe before the procedure. Linear regression analysis and receiver operator characteristic (ROC) curve were used to assess the association between ONSD and ICP. Optimal cut-off value for identifying IICP was defined. Results A total of 62 patients who underwent ONSD measurement with simultaneous EVD catheter placement were enrolled in this study. Thirty-two patients (51.6%) were found to have IICP. ONSD in patients with IICP (5.80 ± 0.45 mm) was significantly higher than in those without IICP (5.30 ± 0.61 mm) (P < 0.01). The IICP group showed more significant linear correlation with ONSD (r = 0.57, P < 0.01) compared to the non-IICP group (r = 0.42, P = 0.02). ONSD > 5.6 mm disclosed a sensitivity of 93.75% and a specificity of 86.67% for identifying IICP. Conclusion ONSD as seen on bedside US correlated well with directly measured ICP in Korean adults with brain lesions. The optimal cut-off point of ONSD for detecting IICP was 5.6 mm.

Hemifacial Spasm Developed after Contralateral Vertebral Artery Ligation

Although the mechanism of hemifacial spasm (HFS) is not yet well established, vascular compression of the facial nerve root exit zone and hyperexcitability of the facial nucleus have been suggested. We report a case of HFS in the setting of coinciding intracranial hemorrhage (ICH) of the pons and proximal ligation of the contralateral vertebral artery (VA) for the treatment of a fusiform aneurysm of the distal VA and discuss the possible etiologies of HFS in this patient. A 51-year-old male with an ICH of the pons was admitted to our hospital. Neuroimaging studies revealed an incidental fusiform aneurysm of the right VA distal to the origin of the posterior inferior cerebellar artery. Eight months after proximal ligation of the VA the patient presented with intermittent spasm of the left side of his face. Pre- and post-ligation magnetic resonance angiography revealed an enlarged diameter of the VA. The spasm completely disappeared after microvascular decompression.

Dynamic Radiographic Results of Different Semi-Rigid Fusion Devices for Degenerative Lumbar Spondylolisthesis: "Dynamic Rod" vs. "Dynamic Screw Head".

AIM To assess the clinical outcomes and compare the segmental range of motion (ROM) at the implanted L4-L5 level, the cranial and caudal adjacent levels, and the ROM of the whole lumbar spine after semi-rigid lumbar fusion with 2 different devices. MATERIAL AND METHODS Patients with neurogenic claudication, due to grade 1 spondylolisthesis and spinal stenosis at levels L4-L5, were treated either Bio-flex® (n = 28) and Cosmic® (n = 23); discectomy was not performed at any level. The clinical outcomes were compared between the 2 groups. All patients underwent neutral, flexion, and extension radiography before the surgery and after 2 years postoperatively. ROM was assessed at the level of L4-L5, L3-L4, L5-S1, and at the whole lumbar spine. RESULTS According to clinical outcomes, 82% and 78% of patients in the BioFlex and Cosmic groups, respectively, had a good or excellent result. In both groups, there was significant reduction of the segmental ROM at the implanted L4-L5 level (p = 0.039 and 0.011). CONCLUSION These outcomes may play a role in decreasing the risk of ASD after dynamic stabilization, at least 2 years after surgery.

Factors Associated With Longer Postoperative Outpatient Follow-up Duration in Patients With Single Lumbar Disc Herniation: A Noncomplicated Patient Cohort Study

Objective Many reports have described the outcomes of surgical treatment of lumbar disc herniation (LDH). However, few reports have investigated the treatment period after lumbar disc surgery. If no complications occur, how long should an ordinary patient be treated? Which factors are associated with the outpatient follow-up period (OFP)? To answer these questions, we reviewed the medical records of patients who underwent lumbar disc surgery, calculated their average OFP, and sought to identify factors associated with the OFP. Methods Patients who underwent surgical treatment of single-level LDH from July 2005 to December 2011 were enrolled in this study. Patients who had no pain or required no further treatment did not receive follow-up. Patients’ medical records were reviewed retrospectively. Cases of recurrent LDH, postoperative infections, instrumentation, cauda equina syndrome, postoperative hematoma, trauma-associated herniation, and spondylolisthesis were excluded. We reviewed the postoperative hospitalization period (PHP) and the OFP. Sex, age, operation year, surgical approach, the operating surgeon, disc level, and insurance type were investigated as associated factors. Results In total, 611 patients underwent surgical treatment for single-level LDH by 4 surgeons. Their average age was 44.3 ± 15.1 years. There were 377 male and 234 female patients. The average PHP was 4.4 ± 3.2 days, the average OFP was 112.3 ± 198.6 days, and the 95% confidence interval for the OFP among the enrolled patients was between 96.5 and 128.1 days. Conclusion Although this is a single-institute report, most LDH patients showed an OFP of less than 4 months after surgical treatment. In this study, sex, age, and insurance type seemed to be related with the OFP.

Protected versus Unprotected Carotid Artery Stenting : Meta-Analysis of the Current Literature

Objective To compare peri-operative any symptomatic stroke after carotid angioplasty and stenting (CAS), based on the application or absence of a cerebral protection device. Methods A systematic literature review using PubMed, Embase, and the Cochrane Central was done across an online data base from January 1995 to October 2016. Procedures which were performed due to carotid dissection or aneurysm, procedures using covered stents or conducted in an emergency, were excluded. The primary endpoint was perioperative any symptomatic stroke within 30 days after the procedure. A fixed effect model was used in cases of heterogeneity less than 50%. Results In the 25 articles included in this study, the number of stroke events was 326 (2.0%) in protected CAS and 142 (3.4%) in unprotected CAS. The use of cerebral protection device significantly decreased stroke after CAS (odds ratio [OR] 0.633, 95% confidence interval [CI] 0.479–0.837, p=0.001). In the publication bias analysis, Egger’s regression test disclosed that the intercept was -0.317 (95% CI -1.015–0.382, p=0.358). Regarding symptomatic patients (four studies, 539 CAS procedures), the number of stroke was six (1.7%) in protected CAS and 11 (5.7%) in unprotected CAS. The protective effect against stroke events by cerebral protection device did not have a statistical significance (OR 0.455, 95% CI 0.151–1.366, p=0.160). Conclusion The use of protection device significantly decreased stroke after CAS. However, its efficacy was not demonstrated in symptomatic patients. Routine use of protection device during CAS should be critically assessed before mandatory use.