Low-Level Environmental Mercury Exposure and Thyroid Cancer Risk Among Residents Living Near National Industrial Complexes in South Korea: A Population-Based Cohort Study.

Background: Previous studies suggested that mercury may be linked to thyroid cancer due to its bioaccumulation in the thyroid gland, but no studies have evaluated the association between mercury exposure and thyroid cancer risk. We examined the relationship between mercury exposure and thyroid cancer risk, with the potential modification of hematological parameters. Methods: We performed a secondary analysis of a prospective cohort study among residents living near industrial complexes in South Korea (recruited from 2003 to 2011). Incident thyroid cancer cases (C73, ICD-10 code) were identified from the National Cancer Registry and Statistics Korea. Urinary mercury concentrations were measured using thermal decomposition amalgamation atomic absorption spectrometry (TDA-AAS). Cox proportional hazards regression models (adjusted for age, sex, educational level, smoking status, and employment) were used to estimate the hazard ratio (HR) and confidence interval [CI] between mercury exposure and the incidence of thyroid cancer. Results: We documented 69 cases of thyroid cancer in a total of 5213 participants during follow-up (median 8.7 years). The geometric mean of urinary mercury concentration was 1.8 µg/L for thyroid cancer cases and 1.2 µg/L for noncases (p for difference = 0.001). After adjusting for potential confounders, those in the highest tertile of urinary mercury levels had a twofold higher risk of thyroid cancer (HR = 1.97 [CI 1.03 - 3.80] in the highest tertile vs. the lowest tertile, p for trend = 0.043). This association was stronger for those with lower mean corpuscular volume and mean corpuscular hemoglobin status. Conclusions: Urinary mercury concentration was positively associated with the risk of thyroid cancer among residents living near national industrial complexes, and this association was influenced by red blood cell indices status. These results provide some evidence suggesting the adverse effects of environmental metal pollution in the development of thyroid cancer.

Environmental health survey for children residing near mining areas in South Gobi, Mongolia.

BACKGROUND: We evaluated the level and factors of heavy metal exposure to children residing in the Togttsetsii, Khanbogd, and Bayandalai soums of South Gobi province, Mongolia. METHODS: A total of 118 children aged 9-12 years were surveyed, and the level of heavy metal exposure in their bodies was investigated. Exposure was investigated by measuring concentrations of heavy metals such as cadmium, lead, and mercury in the blood; mercury concentration in the hair; and total arsenic in the urine. RESULTS: Blood cadmium concentration had geometric averages of 0.16 µg/L in the children from Bayandalai, 0.15 µg/L Tsogttsetsii, and 0.16 µg/L Khanbogd. Blood lead concentration showed a relatively higher geometric average of 7.42 µg/dL in the children from Bayandalai compared to 4.78 µg/dL and 5.15 µg/dL in those from Tsogttsetsii and Khanbogd, respectively. While blood mercury concentration was the highest in the children from Bayandalai, with a value of 0.38 µg/L, those from Tsogttsetsii and Khanbogd had similar concentrations of 0.29 µg/L and 0.29 µg/L, respectively. Hair mercury concentration was the highest in the children from Bayandalai, with a value of 78 µg/g, a particularly significant difference, with a concentration of 0.50 µg/g in those from Khanbogd. Urine arsenic concentration was the highest in the children from Khanbogd, with a value of 36.93 µg/L; it was 26.11 µg/L in those from Bayandalai and 23.89 µg/L in those from Tsogttsetsii. CONCLUSIONS: The high blood lead concentration of children in Bayandalai was judged to be due to other factors in addition to mine exposure; the reason why blood and hair mercury concentration was higher in children from Bayandalai may have been due to exposure to many small-scale gold mines in the area. In the case of Khanbogd, it was estimated that the high arsenic level in urine was caused by the effect of mines.

Toluene concentrations in the blood and risk of thyroid cancer among residents living near national industrial complexes in South Korea: A population-based cohort study.

BACKGROUND: Toluene is classified as a possible carcinogen, but its role on thyroid cancer is not well established. Vehicle emissions are one of the largest contributed sources of toluene, but no studies evaluating the influence of living near a road on the association between toluene and the incidence of thyroid cancer have been reported. Therefore, we examined potential associations between blood toluene concentrations and incidence risk of thyroid cancer, and an effect modification of living near a road. METHODS: We conducted a prospective cohort study using data from South Korean "Monitoring Project for Exposure to Environmental Pollutants and Health Effects among Residents Living near Industrial Complexes" survey. Study participants living near national industrial complexes were recruited from January 2003 to 2011. Incidence and mortality cases of thyroid cancer (C73, ICD-10 code) were identified using the National Cancer Registry and Statistics Korea, respectively. Blood toluene concentrations were measured using gas chromatography mass spectrometry. We used Cox proportional hazards regression models to estimate the hazard ratios (HR) and the 95% confidence interval (CI) between blood toluene concentrations and thyroid cancer risk. RESULTS: During the follow-up (median 8.6 years), 33 cases of thyroid cancer were diagnosed. The geometric mean of the toluene concentration in the blood was 0.56 µg/L for cases and 0.29 µg/L for non-cases. After adjusting for potential confounders, a positive association between blood toluene concentrations and thyroid cancer was found (HR = 2.77, 95% CI = 1.00-7.65 in the highest tertile vs. the lowest tertile, p for trend = 0.044). This positive association was stronger in people living near a road (≤50 m). CONCLUSIONS: Blood toluene concentrations may be positively associated with the incidence risk of thyroid cancer. Moreover, this association may be stronger among people living near a road.

Environmental exposure to cadmium and risk of thyroid cancer from national industrial complex areas: A population-based cohort study.

BACKGROUND: Cadmium is known to act as a thyroid disruptor and carcinogen in humans. Recent evidence suggests that cadmium may play a role as a thyroid carcinogen due to its endocrine-disrupting activity, but this characterization remains unclear. OBJECTIVE: We investigated the association between urinary cadmium and primary thyroid cancer, and the modifying effect of diabetes on this association. METHODS: We included 5406 participants over 19 years old with measured urinary cadmium from samples collected at eight National Industrial Complex areas from 2003 to 2011. Among 5406 participants, 68 cases were diagnosed with thyroid cancer between enrollment and the end of follow-up (December 31, 2016). Incidence rate ratios for thyroid cancer were estimated using random-effects Cox proportional hazards models with follow-up time as the time scale. In addition, we conducted a stratified analysis by diabetes status. RESULTS: Compared with the lowest tertile, the middle and highest tertiles had higher risks of thyroid cancer, respectively (HRmiddle vs. lowest = 1.90, 95% CI = 0.93 to 3.91; HRhighest vs. lowest = 2.28, 95% CI = 1.09 to 4.78), with a significant dose-response relationship (P for trend = 0.03). There was no linear association between cadmium level and risk of thyroid cancer. Higher cadmium levels increased thyroid cancer risk in participants without diabetes (HRmiddle vs. lowest = 2.35, 95% CI = 1.05 to 5.24; HRhighest vs. lowest = 2.70, 95% CI = 1.18 to 6.19); although, an association between cadmium levels and thyroid cancer risk in participants with diabetes was not found. CONCLUSION: Low-level exposure to cadmium is associated with thyroid cancer risk. Our results provide the evidence to limit exposure to cadmium for cancer prevention in the general population. Further studies are needed to investigate the consequence of diabetes and antidiabetic drugs between cadmium and thyroid cancer.

Technical Considerations in Endoscopic Lumbar Decompression.

With technical development and evolution of endoscopic instruments, endoscopic spinal surgery has become one of the standard treatments for various lumbar spinal diseases ranging from a simple contained disc to complicated cases such as highly migrated disc herniation and other pathology combined with bony degeneration to produce foraminal and canal stenosis. Favorable clinical results of endoscopic decompression for lumbar stenotic disease were reported by several authors. However, studies have also reported limitations, such as steep learning curves and a relatively high complication rate compared with conventional techniques. The endoscopic lumbar decompression technique consists of many essential skills to manage different endoscopic anatomic structures of the spine. From the perspective of surgical completion and safety, this article discusses issues related to technical considerations in endoscopic lumbar decompression.

The Biportal Endoscopic Posterior Cervical Inclinatory Foraminotomy for Cervical Radiculopathy: Technical Report and Preliminary Results.

The purpose of the current study was to introduce a surgical technique for posterior cervical inclinatory foraminotomy (PCIF) using a percutaneous biportal endoscopic (BE) approach. Consecutive 7 patients underwent BE-PCIF for their cervical radiculopathy. Postoperative radiologic images (x-rays, computed tomography [CT], and magnetic resonance imaging [MRI]) were evaluated postoperatively for optimal neural decompression status and stability. A visual analogue scale (VAS) for the arm pain and the Neck Disability Index were used to evaluate clinical results in the preoperative and postoperative periods. Mean follow-up periods were 6.42 ± 2.99 months. The mean operative time was 101.42 ± 49.30 minutes. Postoperative MRI and CT revealed complete removal of herniated discs and ideal neural decompression of the treated segments in all patients. Disc height and stability were preserved on postoperative x-rays. Preoperative VAS and Oswestry Disability Index scores improved significantly after the surgery. BE-PCIF may be an effective surgical treatment of the cervical radiculopathic lesions, which provides successful surgical decompression as far as distal part of foramen with better operative view and more easy surgical manipulation. This approach may also minimize iatrogenic damages of the posterior cervical musculo-ligamentous structures and help to maximize the preservation of the facet joint.

Comparison of Short-Term Associations between PM2.5 Components and Mortality across Six Major Cities in South Korea.

Association between short-term exposure to fine particulate matter (PM2.5) and mortality or morbidity varies geographically, and this variation could be due to different chemical composition affected by local sources. However, there have been only a few Asian studies possibly due to limited monitoring data. Using nationwide regulatory monitoring data of PM2.5 chemical components in South Korea, we aimed to compare the associations between daily exposure to PM2.5 components and mortality across six major cities. We obtained daily 24-h concentrations of PM2.5 and 11 PM2.5 components measured from 2013 to 2015 at single sites located in residential areas. We used death certificate data to compute the daily counts of nonaccidental, cardiovascular, and respiratory deaths. Using the generalized additive model, we estimated relative risks of daily mortality for an interquartile range increase in each pollutant concentration, while controlling for a longer-term time trend and meteorology. While elemental carbon was consistently associated with nonaccidental mortality across all cities, nickel and vanadium were strongly associated with respiratory or cardiovascular mortality in Busan and Ulsan, two large port cities. Our study shows that PM2.5 components responsible for PM2.5-associated mortality differed across cities depending on the dominant pollution sources, such as traffic and oil combustion.

Percutaneous Endoscopic Decompression in Lumbar Canal and Lateral Recess Stenosis - The Surgical Learning Curve.

OBJECTIVE: The purpose of this study is to characterize the learning curve of endoscopic lumbar decompression based on peri- and postoperative parameters and to suggest the potential of full endoscopic decompression as a primary treatment option for lumbar canal and lateral recess stenosis. METHODS: The records of 223 consecutive patients who underwent percutaneous endoscopic decompression by a single surgeon for their lumbar canal and lateral recess stenosis were reviewed. Patients were stratified into group 1 (n=100) and group 2 (n=123), depending on their case number. After the 100th case, the procedural time reached a plateau and subsequent patients were assigned to the second group. Demographics and surgical outcomes, including operative times, change in dural sac dimensions, length of hospital stay, and intraoperative complication rates were compared between the 2 groups. Postoperative clinical outcomes, including the visual analogue scale (VAS), the Oswestry Disability Index (ODI) and reoperation rates were compared between the 2 groups (group 1, n=90; group 2, n=110) by follow-up evaluation. RESULTS: Procedural times were greater in group 1 than group 2 (group 1, 105.26 minutes; group 2, 67.65 minutes; p<0.05) and they had higher complication rates (group 1, 16% [16 of 100]; group 2, 8.3% [8 of 123]; p<0.05). The length of hospitalization, postoperative improvement in VAS and ODI, and reoperation rates were not different between the groups. In both groups, stenotic spinal canals were effectively decompressed. CONCLUSION: Continued surgical experience was associated with a reduction in operative times and less intraoperative complications. Although the learning curve was steep and additional surgical experience may be needed to overcome the learning curve, percutaneous full endoscopic lumbar decompression is a safe, clinically-feasible, and effective surgical technique and can be adopted as the primary treatment for lumbar canal and lateral recess stenosis.

Biportal Endoscopic Spinal Surgery for Bilateral Lumbar Foraminal Decompression by Switching Surgeon's Position and Primary 2 Portals: A Report of 2 Cases With Technical Note.

Total facetectomy with/without fusion and facet-preserving microforaminotomy have been performed as conventional surgical treatments for lumbar foraminal stenosis (LFS). Recently, endoscopic spinal surgery has been introduced as a minimally invasive therapeutic modality of LFS by several authors. We report two cases of bilateral LFS at lumbosacral junction level successfully treated with a novel biportal endoscopic spine surgery (BES) technique using primary 2 portals. Two patients presented with chronic onset of back pain and neurogenic claudication symptom. They were diagnosed with bilateral LFS at L5-S1 level from magnetic resonance imaging and computed tomography preoperatively. BES for bilateral foraminal decompression was performed via contralateral approach bilaterally without additional skin incision or surgical trajectory by switching surgeon's position and primary 2 portals. After the surgery, preoperative patients' back and leg pain resolved and unilateral leg weakness of the 2 patients gradually improved in a few months. Postoperative radiologic images revealed significantly enlarged bilateral foramens at L5-S1 level.

Comparative Analysis between Three Different Lumbar Decompression Techniques (Microscopic, Tubular, and Endoscopic) in Lumbar Canal and Lateral Recess Stenosis: Preliminary Report.

PURPOSE: The purpose of our study is to compare the results of spinal decompression using the full-endoscopic interlaminar technique, tubular retractor, and a conventional microsurgical laminotomy technique and evaluate the advantages and clinical feasibility of minimally invasive spinal (MIS) lumbar decompression technique in the lumbar canal and lateral recess stenosis. METHODS: The authors retrospectively reviewed clinical and radiological data from 270 patients who received microsurgical (group E: 72 patients), tubular (group T: 34 patients), or full-endoscopic decompression surgery (group E: 164 patients) for their lumbar canal and lateral recess stenosis from June 2016 to August 2017. Clinical (VAS, ODI, and Mcnab criteria), radiologic (spinal canal diameter, segmental dynamic angle, and disc height), and surgical outcome parameters (CPK level, Operative time, blood loss, and hospital stay) were evaluated pre- and postoperatively and compared among the three groups by means of statistical analysis. Failed cases and complications were reviewed in all groups. RESULTS: The mean follow-up period was 6.38 months. The Overall clinical success rate was 89.4%. All groups showed favorable clinical outcome. The clinical and radiologic results were similar in all groups. Regarding surgical outcome, group E showed longer operation time than group M and T (group E: 84.17 minutes/level, group M: 52.22 minutes/level, and group T: 66.12 minutes/level) (p<0.05). However, groups E and T showed minimal surgical invasiveness compared with group M. Groups E and T showed less immediate postoperative back pain (VAS) (group E: 3.13, group M: 4.28, group T: 3.54) (p<0.05), less increase of serum CPK enzyme (group E: 66.38 IU/L, group M: 120 IU/L, and group T: 137.5 IU/L) (p<0.05), and shorter hospital stay (group E: 2.12 days, group M: 4.85 days, and group T: 2.83 days) (p<0.05). The rates of complications and revisions were not significantly different among the three groups. CONCLUSIONS: MIS decompression technique is clinically feasible and safe to treat the lumbar canal and lateral recess stenosis, and it has many surgical advantages such as less muscle trauma, minimal postoperative back pain, and fast recovery of the patient compared to traditional open microscopic technique.

The Usefulness of Percutaneous Endoscopic Technique in Multifocal Lumbar Pathology.

Introduction. The multifocal lumbar pathology including disc herniation and stenosis in the spinal canal or foramen has been considered the most difficult to approach surgically. It often requires mandatory dual approaches and/or fusion techniques. Traditional percutaneous endoscopic lumbar transforaminal and interlaminar approach has been focused on unifocal disc herniation. However, the development of endoscopic spinal instruments and surgical technique has broadened surgical indication and therapeutic boundary in endoscopic spine surgery. Cases Presentation. The authors present outcomes of four patients with multilumbar pathology including highly inferior migrated disc combined with lateral recess stenosis, multifocal disc herniation, bilateral disc herniations in spinal canal and foraminal disc herniation combined with central canal stenosis. They were successfully treated by percutaneous uniportal full endoscopic approach with single incision. Conclusion. Percutaneous endoscopic spine surgery is a safe and effective tool to figure out multilumbar pathology in a minimal invasive way.

Surgical Treatment of Extraforaminal Gas-Containing Pseudocyst Compressing L5 Nerve Root by Using Unilateral Biportal Endoscopy.

BACKGROUND: Most gaseous lumbar pseudocysts have been previously reported to be located in the spinal canal and successfully treated by several therapeutic methods. By comparison, a gas-containing pseudocyst in the lumbar extraforaminal area is rare. Here, the authors report a case of symptomatic gas-containing cyst located in the lumbar foramen. It was successfully treated with unilateral biportal endoscopic (UBE) surgery. CASE DESCRIPTION: A 75-year-old man presented with severe left leg pain and tingling sensation refractory to conservative treatment that aggravated with weight bearing and position change. Computed tomography and magnetic resonance imaging showed a gas-containing cyst compressing the left L5 nerve root ganglion in the foramina area at the L5-S1 level. Gaseous extraforaminal pseudocyst was successfully removed by UBE surgery via the paraspinal approach. Vivid and clear endoscopic operative imaging of pseudocyst in detail was obtained during the operation. The patient's symptom was significantly improved after the operation. CONCLUSIONS: A gas-containing pseudocyst in the lumbar foraminal area is not common. Combined use of preoperative magnetic resonance imaging and computed tomography can help diagnose a gaseous pseudocyst and differentiate other pathologies. A UBE technique that provides good operative visualization and delicate operative manipulation is a less invasive therapeutic method to treat a foraminal gas-containing pseudocyst.

Synthesis and Characterization of Co-Mn (O)OH Nanosheets Assembled Structure Covered of Reduced Graphene Oxide Hybrid Structures by Hydrothermal Method.

In this study, we prepared cobalt-manganese (oxy) hydroxide nanosheets assembled structure covered of reduced graphene oxide hybrid structure (Co-Mn (O)OH NAS@rGO HS) via reduction and hydroxylation of Mn1.5Co1.5[Co(CN)6]2@graphene oxide (GO). Obtained precursors were optimized at 15 mg GO, and these are hybrid structures in which nanocubes 200-400 nm in size were fully covered by multi-layered GO. The functional group (-COOH, -OH, C-O-C) of GO was removed through reduction by L-ascorbic acid. We obtained MnCOOH, Co(OH)2, and Co-Mn LDH synthesized by hydroxylation of Mn1.5Co1.5[Co(CN)6]2@GO via ion exchange between the CN group and OH-. The hybrid nanostructure between transition-metal oxide/hydroxide and reduced graphene oxide could be used in various fields, including lithium ion batteries, supercapacitors, and electrocatalyst for water splitting.

Percutaneous Endoscopic Laminotomy with Flavectomy by Uniportal, Unilateral Approach for the Lumbar Canal or Lateral Recess Stenosis.

OBJECTIVE: To evaluate clinical feasibility and safety of percutaneous endoscopic decompression by a uniportal, unilateral approach for lumbar canal or lateral recess stenosis. METHODS: In this retrospective study, the procedure was performed with endoscopic instruments in the same way as conventional microscopic laminotomy and flavectomy. Clinical outcomes (visual analog scale, Oswestry Disability Index, modified MacNab criteria) were evaluated. Surgical outcomes, including operative time, hospital stay, and complications, were recorded. RESULTS: Decompression was performed in 213 patients (232 lumbar levels) for spinal canal or lateral recess stenosis (unilateral laminotomy, n = 80; bilateral laminotomy, n = 152). Mean follow-up period was 26.45 months. Mean visual analog scale for leg pain, and back pain and mean Oswestry Disability Index improved from 8.24%, 5.35%, and 67.8% at baseline to 1.93% (P < 0.001), 2.05% (P < 0.001), and 17.14% (P < 0.001) at final follow-up. Based on modified MacNab criteria, excellent or good results were obtained in 93.8% of patients. Average operative time was 105.3 ± 56 minutes. In the late period of the learning curve, mean operative time was shortened by two thirds, and mean hospital stay was 2.45 days. There were 12 cases of transient postoperative dysesthesia, 3 cases of motor weakness, and 6 cases of dural tear. No patient had postoperative infection, hematoma, or need for revision surgery for incomplete decompression. CONCLUSIONS: Percutaneous endoscopic decompression by a uniportal, unilateral approach is a safe, clinically feasible, and effective surgical technique for treatment of lumbar stenosis.

Increase in nitrite content and functionality of ethanolic extracts of Perilla frutescens following treatment with atmospheric pressure plasma.

This study investigated the effect of atmospheric pressure plasma (APP) treatment on nitrite content and functionality of plant extracts. Ethanolic extracts of Perilla frutescens (EEP) were prepared and treated with APP for 60min. Nitrite content increased from 0 to 45.8mg/l in EEP after APP treatment for 60min. Antimicrobial activity of EEP against Clostridium perfringens and Salmonella Typhimurium was increased by APP with no influence on antioxidative activity (p<0.05). Lyophilized EEP (LEEP) treated with APP for 60min contained 3.74mg/g nitrite. The control (LEEP without APP) contained no nitrite. The minimum inhibitory concentration (MIC) of LEEP for C. perfringens was 200µg/ml. The control did not inhibit C. perfringens growth between 25 and 1000µg/ml. MICs of LEEP and the control against S. Typhimurium were 25 and 50µg/ml, respectively. New nitrite sources with increased antimicrobial activity can be produced from natural plants by APP treatment.

Which Approach Is Advantageous to Preventing Development of Adjacent Segment Disease? Comparative Analysis of 3 Different Lumbar Interbody Fusion Techniques (ALIF, LLIF, and PLIF) in L4-5 Spondylolisthesis.

OBJECTIVE: The purpose of this study was to compare radiologic and clinical outcomes in patients with L4-5 lumbar spondylolisthesis who have undergone either instrumented anterior lumbar interbody fusion (ALIF), lateral lumbar interbody fusion (LLIF), or posterior lumbar interbody fusion (PLIF), especially with regard to the development of adjacent segment disease (ASD). METHODS: Eighty-two patients with preoperative L4-5 spondylolisthesis and minimal ASD who underwent instrumented L4-5 fusion were divided into 3 groups according to the surgical approach used for treatment (ALIF: 27 patients, LLIF: 24 patients, PLIF: 31 patients). Radiographic measurements including preoperative and postoperative foraminal and disk height, segmental and lumbar lordosis, percentage of vertebral slippage, and reduction rate were reviewed. The incidence of ASD and clinical outcomes were evaluated and compared between the 3 groups. RESULTS: ASD was found in 37.0% (10/27), 41.7% (10/24), and 64.5% (20/31) of the patients in the ALIF, LLIF, and PLIF groups, respectively (mean follow-up duration: 35.42 ± 9.35 months). The ALIF and LLIF groups had significantly increased disk and foraminal height compared with the PLIF group. The ALIF group had significantly improved lordosis compared with the PLIF and LLIF groups. There were no statistically significant intergroup differences in clinical outcomes assessed by visual analog scale and Oswestry Disability Index. CONCLUSION: The 3 different fusion techniques investigated can all produce good outcomes in treating lumbar spondylolisthesis in L4-5, but ALIF and LLIF are more advantageous in preventing the development of ASD.

Foraminoplastic Superior Vertebral Notch Approach with Reamers in Percutaneous Endoscopic Lumbar Discectomy : Technical Note and Clinical Outcome in Limited Indications of Percutaneous Endoscopic Lumbar Discectomy.

To describe the details of the foraminoplastic superior vertebral notch approach (FSVNA) with reamers in percutaneous endoscopic lumbar discectomy (PELD) and to demonstrate the clinical outcomes in limited indications of PELD. Retrospective data were collected from 64 patients who underwent PELD with FSVNA from August 2012 to April 2014. Inclusion criteria were high grade migrated disc, high canal compromised disc, and disc protrusion combined with foraminal stenosis. The clinical outcomes were assessed using by the visual analogue scale (VAS), Oswestry Disability Index (ODI) and modified MacNab criteria. Complications related to the surgery were reviewed. The procedure used a unique approach, using the superior vertebral notch as the target and performing foraminoplasty with only reamers under C-arm control. The mean age of the 55 female and 32 male patients was 52.73 years. The mean F/U period was 12.2±4.2 months. Preoperative VAS (8.24±1.25) and ODI (67.8±15.4) score improved significantly at the last follow-up (VAS, 1.93±1.78; ODI, 17.14±15.7). Based on the modified MacNab criteria, excellent or good results were obtained in 95.3% of the patients. Postoperative transient dysthesia (n=2) and reoperation (n=1) due to recurred disc were reported. PELD with FSVNA could be a good method for treating lumbar disc herniation. This procedure may offer safe and efficacious results, especially in the relatively limited indications for PELD.

Radicular compression by intraspinal epidural gas bubble occurred in distant two levels after lumbar microdiscectomy.

The authors report a case of symptomatic epidural gas accumulation 2 weeks after the multi-level lumbar surgery, causing postoperative recurrent radiculopathy. The accumulation of epidural gas compressing the dural sac and nerve root was demonstrated by CT and MRI at the distant two levels, L3-4 and L5-S1, where vacuum in disc space was observed preoperatively and both laminectomy and discectomy had been done. However, postoperative air was not identified at L4-5 level where only laminectomy had been done in same surgical field, which suggested the relationship between postoperative epidural gas and the manipulation of disc structure. Conservative treatment and needle aspiration was performed, but not effective to relieve patient's symptoms. The patient underwent revision surgery to remove the gaseous cyst. Her leg pain was improved after the second operation.

Morphometric Relationship between the Cervicothoracic Cord Segments and Vertebral Bodies.

OBJECTIVE: The objective of this study was to investigate the morphologic characteristics between the vertebral body and the regions of the cervical and thoracic spinal cords where each rootlets branch out. METHODS: Sixteen adult cadavers (12 males and 4 females) with a mean age of 57.9 (range of 33 to 70 years old) were used in this study. The anatomical relationship between the exit points of the nerve roots from the posterior root entry zone at each spinal cord segment and their corresponding relevant vertebral bodies were also analyzed. RESULTS: Vertical span of the posterior root entry zone between the upper and lower rootlet originating from each spinal segment ranged from 10-12 mm. The lengths of the rootlets from their point of origin at the spinal cord to their entrance into the intervertebral foramen were 5.9 mm at the third cervical nerve root and increased to 14.5 mm at the eighth cervical nerve root. At the lower segments of the nerve roots (T3 to T12), the posterior root entry zone of the relevant nerve roots had a corresponding anatomical relationship with the vertebral body that is two segments above. The posterior root entry zones of the sixth (94%) and seventh (81%) cervical nerve roots were located at a vertebral body a segment above from relevant segment. CONCLUSION: Through these investigations, a more accurate diagnosis, the establishment of a better therapeutic plan, and a decrease in surgical complications can be expected when pathologic lesions occur in the spinal cord or vertebral body.

Anesthetic experience of a patient with hereditary factor XI deficiency (Hemophilia C) : A case report.

Factor XI deficiency (also called Hemophilia C) rarely occurs among ethnicities other than Ashkenazi Jews. A boy was scheduled for frontoethmoidectomy due to bilateral chronic rhinosinusitis. He was incidentally found to have factor XI deficiency due to prolonged aPTT on preoperative laboratory finding. His medical history reveals frequent epistaxis 2 or 3 times per day and his factor XI and XII activity were 17% (normal; 60-140%) and 34% (normal; 60-140%), respectively on furthermore laboratory evaluation. He was diagnosed as hereditary factor XI deficiency. He underwent the operation with administration of the fresh frozen plasma without complication.