The Importance of Lamina Size Measurement and Proper Implants Selection before Laminoplasty : Two Case Reports / 고신대학교의과대학학술지

Open door laminoplasty using plates is a safe and effective procedure for multi-level cord compression. To achieve stable laminar arch, various types of plate have been developed and used. Now, we introduce two rare complications related to the laminar shelf of plate. In the first case, we used the wider laminar shelf plate because the elevated lamina did not fit well into the usual laminar shelf. During follow-up, cord compression due to laminar shelf was observed. And in the second case, the laminar shelf of plate did not fit into the elevated lamina, so we inserted it with a little bit of force. But the patient’s symptom was not improved. On CT image, the inner cortical bone of the lamina was fractured. To prevent these complications, surgeons need to consider the thickness of the lamina and the size of the laminar shelf before surgery.

Successful Motor Evoked Potential Monitoring in Cervical Myelopathy : Related Factors and the Effect of Increased Stimulation Intensity

Objective@#: Intraoperative neurophysiological monitoring (IONM) has been widely used during spine surgery to reduce or prevent neurologic deficits, however, its application to the surgical management for cervical myelopathy remains controversial. This study aimed to assess the success rate of IONM in patients with cervical myelopathy and to investigate the factors associated with successful baseline monitoring and the effect of increasing the stimulation intensity by focusing on motor evoked potentials (MEPs). @*Methods@#: The data of 88 patients who underwent surgery for cervical myelopathy with IONM between January 2016 and June 2018 were retrospectively reviewed. The success rate of baseline MEP monitoring at the initial stimulation of 400 V was investigated. In unmonitorable cases, the stimulation intensity was increased to 999 V, and the success rate final MEP monitoring was reinvestigated. In addition, factors related to the success rate of baseline MEP monitoring were investigated using independent t-test, Wilcoxon rank-sum test, chi-squared test, and Fisher’s exact probability test for statistical analysis. The factors included age, sex, body mass index, diabetes mellitus, smoking history, symptom duration, Torg-Pavlov ratio, space available for the cord (SAC), cord compression ratio (CCR), intramedullary increased signal intensity (SI) on magnetic resonance imaging, SI length, SI ratio, the Medical Research Council (MRC) grade, the preoperative modified Nurick grade and Japanese Orthopedic Association (JOA) score. @*Results@#: The overall success rate for reliable MEP response was 52.3% after increasing the stimulation intensity. No complications were observed to be associated with increased intensity. The factors related to the success rate of final MEP monitoring were found to be SAC (p<0.001), CCR (p<0.001), MRC grade (p<0.001), preoperative modified Nurick grade (p<0.001), and JOA score (p<0.001). The cut-off score for successful MEP monitoring was 5.67 mm for SAC, 47.33% for the CCR, 3 points for MRC grade, 2 points for the modified Nurick grade, and 12 points for the JOA score. @*Conclusion@#: Increasing the stimulation intensity could significantly improve the success rate of baseline MEP monitoring for unmonitorable cases at the initial stimulation in cervical myelopathy. In particular, the SAC, CCR, MRC grade, preoperative Nurick grade and JOA score may be considered as the more important related factors associated with the success rate of MEP monitoring. Therefore, the degree of preoperative neurological functional deficits and the presence of spinal cord compression on imaging could be used as new detailed criteria for the application of IONM in patients with cervical myelopathy.

Analysis of Platforms and Functions of Mobile-Based Personal Health Record Systems / 대한의료정보학회지

Objectives@#Little is known about the platforms and functionalities of mobile-based personal health record (PHR) applications. The objective of this study was to investigate these two features of PHR systems. @*Methods@#The unit of analysis was general hospitals with more than 100 beds. This study was based on a PHR survey conducted from May 1 to June 30, 2020 and the National Health Insurance administrative data as of March 31, 2020. The study considered the platform, Android and iPhone operation system (iOS), and types of functionalities of PHR systems. Among the 316 target hospitals, 103 hospitals had adopted PHR systems. A logistic regression analysis was used. @*Results@#This study found that 103 hospitals had adopted mobile-based PHR systems for their patients. Sixty-four hospitals (62.1%) were adopting both Android and iOS, but 36 (35.0%) and 3 (2.9%) hospitals were adopting Android only or iOS only, respectively. The PHR systems of hospitals adopting both platforms were more likely to have functions for viewing prescriptions, clinical diagnostic test results, and upcoming appointment status compared to those adopting a single platform (p < 0.001). The number of beds (odds ratio [OR] = 1.004; confidence interval [CI], 1.001–1.007; p = 0.0029) and the number of computed tomography systems (CTs) per 100 beds (OR = 6.350; CI, 1.006–40.084; p = 0.0493) were significantly associated with the adoption of both platforms. @*Conclusions@#More than 60% of hospitals had adopted both Android and iOS platforms for their patients in Korea. Hospitals adopting both platforms had additional functionalities and significant association with the number of beds and CTs.

Computer-based clinical coding activity analysis for neurosurgical terms / 영남의대학술지

BACKGROUND@#It is not possible to measure how much activity is required to understand and code a medical data. We introduce an assessment method in clinical coding, and applied this method to neurosurgical terms.@*METHODS@#Coding activity consists of two stages. At first, the coders need to understand a presented medical term (informational activity). The second coding stage is about a navigating terminology browser to find a code that matches the concept (code-matching activity). Systematized Nomenclature of Medicine – Clinical Terms (SNOMED CT) was used for the coding system. A new computer application to record the trajectory of the computer mouse and record the usage time was programmed. Using this application, we measured the time that was spent. A senior neurosurgeon who has studied SNOMED CT has analyzed the accuracy of the input coding. This method was tested by five neurosurgical residents (NSRs) and five medical record administrators (MRAs), and 20 neurosurgical terms were used.@*RESULTS@#The mean accuracy of the NSR group was 89.33%, and the mean accuracy of the MRA group was 80% (p=0.024). The mean duration for total coding of the NSR group was 158.47 seconds, and the mean duration for total coding of the MRA group was 271.75 seconds (p=0.003).@*CONCLUSION@#We proposed a method to analyze the clinical coding process. Through this method, it was possible to accurately calculate the time required for the coding. In neurosurgical terms, NSRs had shorter time to complete the coding and higher accuracy than MRAs.

Application of Deep Learning System into the Development of Communication Device for Quadriplegic Patient / 대한신경손상학회지

OBJECTIVE: In general, quadriplegic patients use their voices to call the caregiver. However, severe quadriplegic patients are in a state of tracheostomy, and cannot generate a voice. These patients require other communication tools to call caregivers. Recently, monitoring of eye status using artificial intelligence (AI) has been widely used in various fields. We made eye status monitoring system using deep learning, and developed a communication system for quadriplegic patients can call the caregiver. METHODS: The communication system consists of 3 programs. The first program was developed for automatic capturing of eye images from the face using a webcam. It continuously captured and stored 15 eye images per second. Secondly, the captured eye images were evaluated for open or closed status by deep learning, which is a type of AI. Google TensorFlow was used as a machine learning tool or library for convolutional neural network. A total of 18,000 images were used to train deep learning system. Finally, the program was developed to utter a sound when the left eye was closed for 3 seconds. RESULTS: The test accuracy of eye status was 98.7%. In practice, when the quadriplegic patient looked at the webcam and closed his left eye for 3 seconds, the sound for calling a caregiver was generated. CONCLUSION: Our eye status detection software using AI is very accurate, and the calling system for the quadriplegic patient was satisfactory.

The Usefulness of a Wearable Device in Daily Physical Activity Monitoring for the Hospitalized Patients Undergoing Lumbar Surgery

OBJECTIVE: Functional outcomes have traditionally been evaluated and compared using subjective surveys, such as visual analog scores (VAS), the Oswestry disability index (ODI), and Short Form-36 (SF-36), to assess symptoms and quality of life. However, these surveys are limited by their subjective natures and inherent bias caused by differences in patient perceptions of symptoms. The Fitbit Charge® (Fitbit Inc., San Francisco, CA, USA) provides accurate and objective measures of physical activity. The use of this device in patients after laminectomy would provide objective physical measures that define ambulatory function, activity level, and degree of recovery. Therefore, the present study was conducted to identify relationships between the number of steps taken by patients per day and VAS pain scores, prognoses, and postoperative functional outcomes.METHODS: We prospectively investigated 22 consecutive patients that underwent laminectomy for spinal stenosis or a herniated lumbar disc between June 2015 and April 2016 by the same surgeon. When patients were admitted for surgery and first visited after surgery, preoperative and postoperative functional scores were recorded using VAS scores, ODI scores, and SF-36. The VAS scores and physical activities were recorded daily from postoperative day (POD) 1 to POD 7. The relationship between daily VAS scores and daily physical activities were investigated by simple correlation analysis and the relationship between mean number of steps taken and ODI scores after surgery was subjected to simple regression analysis. In addition, Wilcoxon’s signed-rank test was used to investigate the significance of pre-to-postoperative differences in VAS, ODI, and SF-36 scores.RESULTS: Pre-to-postoperative VAS (p<0.001), ODI (p<0.001), SF-36 mental composite scores (p=0.009), and SF-36 physical composite scores (p<0.001) scores were found to be significantly different. Numbers of steps taken from POD 1 to POD 7 were negatively correlated with daily VAS scores (r=-0.981, p<0.001). In addition, the mean number of steps from POD 3 to POD 7 and the decrease in ODI conducted one month after surgery were statistically significant (p=0.029).CONCLUSION: Wearable devices are not only being used increasingly by consumers as lifestyle devices, but are also progressively being used in the medical area. This is the first study to demonstrate the usefulness of a wearable device for checking patient physical activity and predicting pain and prognosis after laminectomy. Based on our experience, the wearable device used to provide measures of physical activity in the present study has the potential to provide objective information on pain severity and prognosis.

Machine Learning Model to Predict Osteoporotic Spine with Hounsfield Units on Lumbar Computed Tomography

OBJECTIVE: Bone mineral density (BMD) is an important consideration during fusion surgery. Although dual X-ray absorptiometry is considered as the gold standard for assessing BMD, quantitative computed tomography (QCT) provides more accurate data in spine osteoporosis. However, QCT has the disadvantage of additional radiation hazard and cost. The present study was to demonstrate the utility of artificial intelligence and machine learning algorithm for assessing osteoporosis using Hounsfield units (HU) of preoperative lumbar CT coupling with data of QCT.METHODS: We reviewed 70 patients undergoing both QCT and conventional lumbar CT for spine surgery. The T-scores of 198 lumbar vertebra was assessed in QCT and the HU of vertebral body at the same level were measured in conventional CT by the picture archiving and communication system (PACS) system. A multiple regression algorithm was applied to predict the T-score using three independent variables (age, sex, and HU of vertebral body on conventional CT) coupling with T-score of QCT. Next, a logistic regression algorithm was applied to predict osteoporotic or non-osteoporotic vertebra. The Tensor flow and Python were used as the machine learning tools. The Tensor flow user interface developed in our institute was used for easy code generation.RESULTS: The predictive model with multiple regression algorithm estimated similar T-scores with data of QCT. HU demonstrates the similar results as QCT without the discordance in only one non-osteoporotic vertebra that indicated osteoporosis. From the training set, the predictive model classified the lumbar vertebra into two groups (osteoporotic vs. non-osteoporotic spine) with 88.0% accuracy. In a test set of 40 vertebrae, classification accuracy was 92.5% when the learning rate was 0.0001 (precision, 0.939; recall, 0.969; F1 score, 0.954; area under the curve, 0.900).CONCLUSION: This study is a simple machine learning model applicable in the spine research field. The machine learning model can predict the T-score and osteoporotic vertebrae solely by measuring the HU of conventional CT, and this would help spine surgeons not to under-estimate the osteoporotic spine preoperatively. If applied to a bigger data set, we believe the predictive accuracy of our model will further increase. We propose that machine learning is an important modality of the medical research field.

The Usefulness of a Wearable Device in Daily Physical Activity Monitoring for the Hospitalized Patients Undergoing Lumbar Surgery

OBJECTIVE: Functional outcomes have traditionally been evaluated and compared using subjective surveys, such as visual analog scores (VAS), the Oswestry disability index (ODI), and Short Form-36 (SF-36), to assess symptoms and quality of life. However, these surveys are limited by their subjective natures and inherent bias caused by differences in patient perceptions of symptoms. The Fitbit Charge® (Fitbit Inc., San Francisco, CA, USA) provides accurate and objective measures of physical activity. The use of this device in patients after laminectomy would provide objective physical measures that define ambulatory function, activity level, and degree of recovery. Therefore, the present study was conducted to identify relationships between the number of steps taken by patients per day and VAS pain scores, prognoses, and postoperative functional outcomes. METHODS: We prospectively investigated 22 consecutive patients that underwent laminectomy for spinal stenosis or a herniated lumbar disc between June 2015 and April 2016 by the same surgeon. When patients were admitted for surgery and first visited after surgery, preoperative and postoperative functional scores were recorded using VAS scores, ODI scores, and SF-36. The VAS scores and physical activities were recorded daily from postoperative day (POD) 1 to POD 7. The relationship between daily VAS scores and daily physical activities were investigated by simple correlation analysis and the relationship between mean number of steps taken and ODI scores after surgery was subjected to simple regression analysis. In addition, Wilcoxon’s signed-rank test was used to investigate the significance of pre-to-postoperative differences in VAS, ODI, and SF-36 scores. RESULTS: Pre-to-postoperative VAS (p<0.001), ODI (p<0.001), SF-36 mental composite scores (p=0.009), and SF-36 physical composite scores (p<0.001) scores were found to be significantly different. Numbers of steps taken from POD 1 to POD 7 were negatively correlated with daily VAS scores (r=-0.981, p<0.001). In addition, the mean number of steps from POD 3 to POD 7 and the decrease in ODI conducted one month after surgery were statistically significant (p=0.029). CONCLUSION: Wearable devices are not only being used increasingly by consumers as lifestyle devices, but are also progressively being used in the medical area. This is the first study to demonstrate the usefulness of a wearable device for checking patient physical activity and predicting pain and prognosis after laminectomy. Based on our experience, the wearable device used to provide measures of physical activity in the present study has the potential to provide objective information on pain severity and prognosis.

Machine Learning Model to Predict Osteoporotic Spine with Hounsfield Units on Lumbar Computed Tomography

OBJECTIVE: Bone mineral density (BMD) is an important consideration during fusion surgery. Although dual X-ray absorptiometry is considered as the gold standard for assessing BMD, quantitative computed tomography (QCT) provides more accurate data in spine osteoporosis. However, QCT has the disadvantage of additional radiation hazard and cost. The present study was to demonstrate the utility of artificial intelligence and machine learning algorithm for assessing osteoporosis using Hounsfield units (HU) of preoperative lumbar CT coupling with data of QCT. METHODS: We reviewed 70 patients undergoing both QCT and conventional lumbar CT for spine surgery. The T-scores of 198 lumbar vertebra was assessed in QCT and the HU of vertebral body at the same level were measured in conventional CT by the picture archiving and communication system (PACS) system. A multiple regression algorithm was applied to predict the T-score using three independent variables (age, sex, and HU of vertebral body on conventional CT) coupling with T-score of QCT. Next, a logistic regression algorithm was applied to predict osteoporotic or non-osteoporotic vertebra. The Tensor flow and Python were used as the machine learning tools. The Tensor flow user interface developed in our institute was used for easy code generation. RESULTS: The predictive model with multiple regression algorithm estimated similar T-scores with data of QCT. HU demonstrates the similar results as QCT without the discordance in only one non-osteoporotic vertebra that indicated osteoporosis. From the training set, the predictive model classified the lumbar vertebra into two groups (osteoporotic vs. non-osteoporotic spine) with 88.0% accuracy. In a test set of 40 vertebrae, classification accuracy was 92.5% when the learning rate was 0.0001 (precision, 0.939; recall, 0.969; F1 score, 0.954; area under the curve, 0.900). CONCLUSION: This study is a simple machine learning model applicable in the spine research field. The machine learning model can predict the T-score and osteoporotic vertebrae solely by measuring the HU of conventional CT, and this would help spine surgeons not to under-estimate the osteoporotic spine preoperatively. If applied to a bigger data set, we believe the predictive accuracy of our model will further increase. We propose that machine learning is an important modality of the medical research field.

Computer-based clinical coding activity analysis for neurosurgical terms / 영남의대학술지

BACKGROUND: It is not possible to measure how much activity is required to understand and code a medical data. We introduce an assessment method in clinical coding, and applied this method to neurosurgical terms.METHODS: Coding activity consists of two stages. At first, the coders need to understand a presented medical term (informational activity). The second coding stage is about a navigating terminology browser to find a code that matches the concept (code-matching activity). Systematized Nomenclature of Medicine – Clinical Terms (SNOMED CT) was used for the coding system. A new computer application to record the trajectory of the computer mouse and record the usage time was programmed. Using this application, we measured the time that was spent. A senior neurosurgeon who has studied SNOMED CT has analyzed the accuracy of the input coding. This method was tested by five neurosurgical residents (NSRs) and five medical record administrators (MRAs), and 20 neurosurgical terms were used.RESULTS: The mean accuracy of the NSR group was 89.33%, and the mean accuracy of the MRA group was 80% (p=0.024). The mean duration for total coding of the NSR group was 158.47 seconds, and the mean duration for total coding of the MRA group was 271.75 seconds (p=0.003).CONCLUSION: We proposed a method to analyze the clinical coding process. Through this method, it was possible to accurately calculate the time required for the coding. In neurosurgical terms, NSRs had shorter time to complete the coding and higher accuracy than MRAs.

Virtual Preoperative Simulation for Excision of Spinal Tumors: Surgeon Processing of Medical Computer-Assisted Design Software

As medical computer-aided design (CAD) has improved, virtual 3-dimensional medical images have been gaining more easily without any special practice. These images can be applied to various clinical fields. This article illustrates virtual preoperative simulation for excision of spinal tumors using medical CAD software. The software was used directly by the surgeon. The process of virtual preoperative simulation for spinal tumor surgery was found to be not inordinately complicated. And, virtual simulation was helpful in determining surgical steps as well as understanding the surgical anatomy.

Cervical Pedicle Screw Placement Using Medial Funnel Technique

OBJECTIVE: Cervical pedicle screw (CPS) placement is very challenging due to high risk of neurovascular complications. We devised a new technique (medial funnel technique) to improve the accuracy and feasibility of CPS placement. METHODS: We reviewed 28 consecutive patients undergoing CPS instrumentation using the medial funnel technique. Their mean age was 51.4 years (range, 30–81 years). Preoperative diagnosis included degenerative disease (n=5), trauma (n=22), and infection (n=1). Screw perforations were graded with the following criteria: grade 0 having no perforation, grade 1 having 50% of screw diameter. Grades 0 and 1 were considered as correct position. The degree of perforation was determined by 2 junior neurosurgeons and 1 senior neurosurgeon. RESULTS: A total of 88 CPSs were inserted. The rate of correct placement was 94.3%; grade 0, 54 screws; grade 1, 29 screws; grade 2, 4 screws; and grade 3, 1 screw. No neurovascular complications or failure of instrumentation occurred. In perforated screws (34 screws), lateral perforations were 4 and medial perforations were 30. CONCLUSION: We performed CPS insertion using medial funnel technique and achieved 94.3% (83 of 88) of correct placement. And it can decrease lateral perforation.

Spontaneous Epidural Hematoma Associated with Venous Phlebolith in Cervical Spine and Possible Pathogenesis

Although the etiology of spontaneous spinal epidural hematoma (SSEH) is unclear, SSEH is known to be associated with anticoagulants, coagulopathy, vascular malformation, hypertension, and pregnancy. However, no report has been issued on the relation between SSEH and venous phlebolith. Here, the authors present an extremely rare case of SSEH associated with phlebolith in the cervical spine and suggest a possible pathogenesis. A 36-year-old man without any relevant medical history presented with neck pain and numbness and severe radiating pain on the left arm. Magnetic resonance imaging showed epidural hematoma at the C5–7 level, and computed tomography revealed a calcified nodule in the left epidural hemorrhage at C6 level. During left partial laminectomy, epidural venous plexus, and thick epidural hematoma were found, and hematoma removal revealed a white, ovoid, smooth, hard mass of diameter 3 mm. Histopathologic examination confirmed the mass as a venous phlebolith. The presence of a calcified solitary nodule in dorsal epidural space indicates the presence of phlebolith and the risk of SSEH. In such cases, the authors recommend spine surgeons should take into consideration the possibility of epidural hemorrhage.

One Stage Posterior Minimal Laminectomy and Video-Assisted Thoracoscopic Surgery (VATS) for Removal of Thoracic Dumbbell Tumor

OBJECTIVE: This study was conducted to assess the surgical results of one-stage posterior minimal laminectomy and video-assisted thoracoscopic surgery (VATS) for the treatment of thoracic dumbbell tumor and to describe its precise technique. In addition, we investigated the technique's usefulness and limitations. METHODS: Seven cases of thoracic dumbbell tumor (two men and five women, mean age, 43 years) were analyzed retrospectively. Pathological findings included schwannoma in four patients, neurofibroma in two patients, and hemangioma in one patient. The location of tumors varied from T2/3 to T12/L1. Dumbbell tumors were resected by one-stage operation using posterior laminectomy followed by VATS without instrumentation. Clinical data were reviewed. RESULTS: The mean follow-up period was 25 months (range, 3–58 months), and the operative time ranged from 255 to 385 min (mean, 331 min), with estimated blood loss ranging from 110 to 930 mL (mean, 348 mL). The tumor was completely resected without instrumentation and postoperative instability in all cases. Postoperative complications included atelectasis and facial anhydrosis in one case each. CONCLUSION: One-stage posterior minimal laminectomy and VATS may be a safe and less invasive technique for removal of thoracic dumbbell tumor without instability. This method has the advantage of early ambulation and rapid recovery because it reduces blood loss and postoperative pain.

Delayed Epidural Mucin Collection after Surgery for Spinal Metastatic Pancreatic Adenocarcinoma

A rare case of delayed large epidural mucin collection causing neurologic deficit after surgery for metastatic pancreatic cancer is reported. A 65-year-old man presented with intractable upper-thoracic back pain radiating to the chest and gait disturbance. He had a history of subtotal pancreatectomy due to intraductal papillary mucinous neoplasm (IPMN) of the pancreas and concurrent chemotherapy. Eight months after pancreatectomy, multiple thoracic spinal metastasis was diagnosed with routine up positron emission tomography-computed tomography. Radiotherapy for spinal metastasis and subsequent chemotherapy was carried out. Sixteen months after pancreatectomy, gait disturbance occurred and follow-up thoracic magnetic resonance imaging (MRI) showed aggravation of metastasis at T2 and T4 compressing the spinal cord. We performed a decompressive laminectomy with subtotal resection of the tumor masses and pedicle screw fixation at C7–T6. Neurologic status improved after the operation. Histopathologic examinations revealed the tumor as metastatic mucin producing adenocarcinoma. Three months after surgery, motor weakness and pain was reappeared. MRI showed large amount of epidural fluid collection. We performed wound revision and there was large amount of gelatinous fluid at the epidural space. We suggest that postoperative mucin collection and wound problems should be considered after surgery for mucin producing metastatic pancreatic tumor.

Infectious Spondylodiscitis by Uncommon Pathogens: A Pitfall of Empirical Antibiotics

OBJECTIVE: The goal of this study is to evaluate the prevalence of spondylodiscitis (SD) caused by uncommon pathogens and review the efficacy of the treatment strategy including the coverage by usual empirical broad-spectrum antibiotic therapy. METHODS: Ninety-nine consecutive patients diagnosed and treated for infectious SD between January 2007 to May 2015 were reviewed retrospectively. The prevalence of uncommon SD, predisposing factors, antibiotics sensitivity, and clinical outcome were analyzed in comparison with that of common SD. RESULTS: Among 99 patients, 68 patients were culture positive. Out of 68 patients with positive culture results, 54 of them(79.4%) were common pathogen and 14 (20.6%) were uncommon pathogen. Postoperative SDs were significantly prevalent in uncommon SD(42.9%) than common SD(27.8%). Recurrence rate was higher in uncommon pathogen SD(14.3%) than common SD group (2.3%), and it showed statistically significant difference (p=0.025). Empirical antibiotics of vancomycin and 3rd or 4th generation cephalosporin covered 100% of nontuberculous common SD and 14.3% of uncommon SD. CONCLUSION: In our study, the prevalence of uncommon SD was relatively high uncommon (20.5% of culture positive SD and 14.1% of total cases) and the coverage rate of empirical antibiotics for them were only 14.3%. In particular, the possibility of SD with fun gal, polymicrobial, or multiple drug resistant organism should be considered in SD unresponsive to broad spectrum antibiotics therapy.

The Applicability of Intraoperative Neuromonitoring in Patients with Preoperative Motor Weakness during Spine Surgery

OBJECTIVE: The purpose of our study is to evaluate the success rate and feasibility of intraoperative neuromonitoring (IONM) focusing on transcranial motor evoked potential (TcMEP) monitoring for patients with preoperative motor weakness in spine surgery. METHODS: Between November 2011 and December 2013, TcMEP and somatosensory evoked potential (SSEP) monitoring were attempted in 130 consecutive patients undergoing spine surgeries for cervical or thoracic cord lesions. Patients ranged in age from 14 to 81 years (mean±standard deviation, 56.7±14.8 years), and 84 patients were male. The success rates of both SSEP and MEPs monitoring were assessed according to the preoperative Medical Research Council (MRC) and Nurick grades. RESULTS: TcMEP was recorded successfully in 0%, 28.6%, 72.3%, and 100% of patients with MRC grades 1, 2, 3, 4, and 5, respectively. SSEP was obtained from 0%, 37.5%, 21.5%, 61.4%, and 85.4% of patients with MRC grades 1, 2, 3, 4, and 5, respectively. TcMEP was recorded successfully in 84% of patients with Nurick grades 1-3 and 26% of patients with Nurick grades 4-5. SSEPs were recorded successfully in 76.3% of patients with Nurick grades 1-3 and 24% of patients with grades 4-5. CONCLUSION: IONM during spine surgery may be useless in patients with MRC grades 1-2, applicable MRC grade 3, and useful MRC grades 4-5. MRC grade 3 is a critical point of indication for application of MEPs. In unmonitorable cases with MRC grade 3, increasing stimulus intensity or facilitation techniques may be considered to improve the usefulness of TcMEP.

Applicability of Thoracolumbar Injury Classification and Severity Score to Criteria of Korean Health Insurance Review and Assessment Service in Treatment Decision of Thoracolumbar Injury

OBJECTIVE: For improving the drawbacks of previous thoracolumbar spine trauma classification, the Spine Trauma Study Group was developed new classification, Thoracolumbar Injury Classification and Severity Score (TLICS). The simplicity of this scoring system makes it useful clinical application. However, considering criteria of Korean Health Insurance Review and Assessment Service (HIRA), the usefulness of TLICS system is still controversial in the treatment decision of thoracolumbar spine injury. METHODS: Total 100 patients, who admitted to our hospital due to acute traumatic thoracolumbar injury, were enrolled. In 45, surgical treatment was performed and surgical treatment was decided following the criteria of HIRA in all patients. With assessing of TLICS score and Denis's classification, the treatment guidelines of TLICS and Denis's classification were applied to the criteria of Korean HIRA. RESULTS: According to the Denis's three-column spine system, numbers of patients with 2 or 3 column injuries were 94. Only 45 of 94 patients (47.9%) with middle column injury fulfilled the criteria of HIRA. According to TLICS system, operation required fractures (score>4) were 31 and all patients except one fulfilled the criteria of HIRA. Conservative treatment required fractures (score<4) were 52 and borderline fracture (score=4) were 17. CONCLUSION: The TLICS system is very useful system for decision of surgical indication in acute traumatic thoracolumbar injury. However, the decision of treatment in TLICS score 4 should be carefully considered. Furthermore, definite criteria of posterior ligamentous complex (PLC) injury may be necessary because the differentiation of PLC injury between TLICS score 2 and 3 is very difficult.

Adverse Drug Reactions of Long-term Intravenous Antibiotics in Patients with Pyogenic Spondylitis

OBJECTIVE: The purpose of this study was to investigate the incidence, cause, and influence of the adverse drug reactions (ADRs) associated with long-term intravenous antibiotics in patients with pyogenic spondylitis (PS). METHODS: We retrospectively reviewed the medical records of 84 patients with PS who underwent intravenous antibiotic therapy in our hospital from January 2001 to December 2012. ADRs were categorized to drug eruption, acute renal failure (ARF), hematologic toxicity, toxic hepatitis, pseudomembranous colitis (PMC), drug fever, and neuronal toxicity. Incidence and onset time of each ADR after antibiotic therapy were analyzed with the incidence of ADRs according to types of antibiotics. RESULTS: ADRs occurred in 38 of the 84 patients (incidence: 45.2%). The use of antibiotics was longer in the patients with ADRs (62.7 days) than in the patients without ADRs (44.3 day). The incidence of drug eruption, ARF, hematologic toxicity, toxic hepatitis, PMC, drug fever, and neuronal toxicity were 22.6, 11.9, 11.9, 10.7, 7.1, 3.6%, and 1.2%, respectively. The duration of antibiotics administration was related to the occurrence of PMC (p=0.001). ADRs were more common in patients treated by glycopeptides including vacomycin and teicoplanin. CONCLUSION: The incidence of ADRs due to long-term intravenous antibiotics was as high as 45.2% in patients with PS. Therefore, we speculate that the possibility of delayed ADRs should be considered after long-term use of the antibiotics. Furthermore, close observation is mandatory to identify and treat ADRs promptly, even though PS revealed the improvement after antibiotic therapy.

Intracranial Extension of Spinal Subarachnoid Hematoma Causing Severe Cerebral Vasospasm

Spinal subarachnoid hemorrhages (SAH) can extend into the intracranial subarachnoid space, but, severe cerebral vasospasm is rare complication of the extension of intracranial SAH from a spinal subarachnoid hematoma. A 67-year-old woman started anticoagulant therapy for unstable angina. The next day, she developed severe back pain and paraplegia. MRI showed intradural and extramedullar low signal intensity at the T2-3, consistent with intradural hematoma. High signal intensity was also noted in the spinal cord from C5 to T4. We removed subarachnoid hematoma compressing the spinal cord. The following day, the patient complained of severe headache. Brain CT revealed SAH around both parietal lobes. Three days later, her consciousness decreased and left hemiplegia also developed. Brain MRI demonstrated multiple cerebral infarctions, mainly in the right posterior cerebral artery territory, left parietal lobe and right watershed area. Conventional cerebral angiography confirmed diffuse severe vasospasm of the cerebral arteries. After intensive care for a month, the patient was transferred to the rehabilitation department. After 6 months, neurologic deterioration improved partially. We speculate that surgeons should anticipate possible delayed neurological complications due to cerebral vasospasm if intracranial SAH is detected after spinal subarachnoid hematoma.