• Journal of Korean Neurosurgical Society
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• v.44 no.3
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• pp.124-130
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• 2008

Objective : Our purpose of this study is to compare insertion angles and screw lengths from Roy-Camille, Magerl, and our designed method for cervical lateral mass screw fixation in the Korean population by quantitative measurement of reformatted two dimensional (2D) computed tomography (CT) images. Methods : We selected thirty Korean patients who were evaluated with thin section CT scans and reconstruction program to obtain reformatted 2D-CT images of the transversal plane passing the cranio-caudal angle using three different techniques. We measured the minimum angle to avoid vertebral artery (VA) injury, the ideal angle and depth for bicortical screwing of cervical lateral mass. Morphometric measurements of the lateral masses from C3-C7 were also taken. Results : In all three techniques, the mean safety angles from the VA were less than 8 degrees and the necessary depth of the screw was about 14 mm for safety to the VA and for the bicortical purchase. In our designed technique, the mean $\beta$ angles of each level from C3 to C7 were 29.0. 29.8. 29.5. 26.3. and 23.9 degrees, respectively. Conclusion : Results of this study and data from the literature indicate that differences may exist between the Korean and Western people in the length and angle for ideal lateral mass screw fixation. In addition, our technique needs further cadaveric and clinical study for safety and efficacy for being performed as alternative method for cervical lateral mass fixation.

• Journal of Korean Neurosurgical Society
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• v.56 no.4
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• pp.330-333
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• 2014

Objective : To identify the accuracy and efficiency of the computed tomographic (CT)-based navigation system on upper cervical instrumentation, particularly C1 lateral mass and C2 pedicle screw fixation compared to previous reports. Methods : Between May 2005 and March 2014, 25 patients underwent upper cervical instrumentation via a CT-based navigation system. Seven patients were excluded, while 18 patients were involved. There were 13 males and five females; resulting in four degenerative cervical diseases and 14 trauma cases. A CT-based navigation system and lateral fluoroscopy were used during the screw instrumentation procedure. Among the 58 screws inserted as C1-2 screws fixation, their precise positions were evaluated by postoperative CT scans and classified into three categories : in-pedicle, non-critical breach, and critical breach. Results : Postoperatively, the precise positions of the C1-2 screws fixation were 81.1% (47/58), and 8.6% (5/58) were of non-critical breach, while 10.3% (6/58) were of critical breach. Most (5/6, 83.3%) of the critical breaches and all of non-critical breaches were observed in the C2 pedicle screws and there was only one case of a critical breach among the C1 lateral mass screws. There were three complications (two vertebral artery occlusions and a deep wound infection), but no postoperative instrument-related neurological deteriorations were seen, even in the critical breach cases. Conclusion : Although CT-based navigation systems can result in a more precise procedure, there are still some problems at the upper cervical spine levels, where the anatomy is highly variable. Even though there were no catastrophic complications, more experience are needed for safer procedure.

• Korean Journal of Veterinary Research
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• v.41 no.2
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• pp.233-241
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• 2001

Dirofilaria immitis, the causative agent of canine heartworm disease, inhabits mainly in the pulmonary arteries and the heart of dogs and cats, causing circulatory and respiratory disorders. Although diagnosis of the disease is based on the presence of microfilaria in the peripheral blood or of specific antigens released from the adult worms into the peripheral blood, the severity of the infection and the assessment of disease progression are based on the clinical signs and radiographic image analysis. We analysed 12 mixed-bred Jindo dogs naturally infected with Dirofilaria immitis without any clinical signs and compared the radiographic images of the heart and the lung with the number of adult worms at necropsy. The dorsoventral radiographs of 12 infected dogs revealed that the right caudal lobar pulmonary arteries (RCaLPA) were dialated in 66.7% of dogs, whereas the main pulmonary artery segment was enlarged in 50.3% of dogs. The cranial lobar pulmonary arteries (RCrLPA) were dilated or pruned in 33.3% of dogs. All dogs displayed the interstitial lung pattern, while the vertebral heart size (VHS) was of normal range. Although a range of 9 to 166 adult worms (av. 45.6) was found in the pulmonary arteries, in the heart or in the vena cava, no correlation with the radiographic findings and/or with the clinical signs was observed.

• Journal of Korean Medicine Rehabilitation
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• v.18 no.4
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• pp.103-120
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• 2008

Objectives : This study aims to educate clinical doctors of the valuable practice of Manipulative Therapy(MT) as an opportunity for evidence-based medicine. Consequently it also serves to review the effectiveness and safety of MT. Methods : The literature studies of overseas were done by Cochrane Library and Medline website; those of domestic researches were completed by utilizing the sources which are gained from KERIS, KISS, DBpia, Kisti, and domestic institutes related with MT. Results : Eight papers related to the effectiveness of MT were published in South Korea, which concluded with the positive effects of MT. None of them are, however, well-designed randomized controlled trials(RCT). On the other hand, fifteen cases of nine articles indicate the adverse reaction of MT, and numbers of the researches in overseas revealed the side effects of MT in order of cervical, lumbar, and thoracic vertebrae. A vascular adverse reaction such as vertebral and carotid artery dissection was a highly reported cervical adverse reaction; in the thoracic and lumbar regions, neurological adverse reaction in terms of disc hemiation was frequently discovered. Conclusions : Henceforth, highly qualitative studies are required developing the effective outcomes and preventing any possible complications of MT. Therefore, systemic curriculums in institutions and sufficient clinical training in the filed are strongly recommended.

• Annals of Rehabilitation Medicine
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• v.42 no.6
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• pp.814-821
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• 2018

Objective To suggest rotation angles of fluoroscopy that can bypass the carotid sheath according to vertebral levels for cervical transforaminal epidural steroid injection (TFESI). Methods Patients who underwent cervical spine magnetic resonance imaging (MRI) from January 2009 to October 2017 were analyzed. In axial sections of cervical spine MRI, three angles to the vertical line (${\alpha}$, angle not to insult carotid sheath; ${\beta}$, angle for the conventional TFESI; ${\gamma}$, angle not to penetrate carotid artery) were measured. Results Alpha (${\alpha}$) angles tended to increase for upper cervical levels ($53.3^{\circ}$ in C6-7, $65.2^{\circ}$ in C5-6, $75.3^{\circ}$ in C4-5, $82.3^{\circ}$ in C3-4). Beta (${\beta}$) angles for conventional TFESI showed a constant value of $45^{\circ}$ to $47^{\circ}$ ($47.5^{\circ}$ in C6-7, $47.4^{\circ}$ in C5-6, $45.7^{\circ}$ in C4-5, $45.0^{\circ}$ in C3-4). Gamma (${\gamma}$) angles increased at higher cervical levels as did ${\alpha}$ angles ($25.2^{\circ}$ in C6-7, $33.6^{\circ}$ in C5-6, $43.0^{\circ}$ in C4-5, $56.2^{\circ}$ in C3-4). Conclusion The risk of causing injury by penetrating major vessels in the carotid sheath tends to increase at upper cervical levels. Therefore, prior to cervical TFESI, measuring the angle is necessary to avoid carotid vessels in the axial section of CT or MRI, thus contributing to a safer procedure.

• Journal of Veterinary Clinics
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• v.39 no.5
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• pp.240-245
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• 2022

A 15-year-old, neutered male, Shih-Tzu, was presented at the Chonnam National Veterinary Medical Teaching Hospital for evaluation of acute onset of persistent coughing, exercise intolerance, and abnormal heart sound. On thoracic auscultation, a split-second heart sound and a wheezing sound were detected on both sides of the chest walls. On physical examination, the dog's body condition score (BCS) was 7/9, and had stenotic nares. Thoracic radiographs revealed right-sided enlargement of the cardiac silhouette (vertebral heart score (VHS) 11.2; reference interval = 8.9-10.1), mild main pulmonary artery (MPA) bulging, mild interstitial infiltration, and hepatomegaly. The electrocardiogram showed right axis deviation, suggesting right ventricular hypertrophy. The echocardiographic study showed moderate pulmonary hypertension and moderate tricuspid regurgitation. There were no findings of a tracheobronchial disease, pulmonary thromboembolism, congenital shunt, left heart disease, or parasitic disease. Based on clinical signs and diagnostic findings, the dog was diagnosed with pulmonary hypertension secondary to brachycephalic syndrome. To rectify respiratory exacerbating factors, the dog was recommended weight control by restricting dietary intake and managing concurrent Cushing's syndrome. Treatments included sildenafil, pimobendan, furosemide, and ramipril. After five months of taking medications and weight control, the severity of pulmonary hypertension improved from moderate to mild. The clinical signs of the patient, including coughing and exercise intolerance, improved a lot. For 5 months of follow-up, the patient has not reported further recurrence of respiratory distress.

• The Journal of the Society of Stroke on Korean Medicine
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• v.7 no.1
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• pp.11-16
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• 2006

Objectives : Transcranial Doppler (TCD) has been reported to be established as useful in detecting spasm after subarachnoid hemorrhage and to be probably useful in diagnosing stenosis or occlusion in intracranial arteries. In the detection of intracranial stenosis using TCD there have been reported some kinds of diagnostic criteria. This study was aimed to evaluate the accordance between TCD and magnetic resonance angiography (MRA) in detection of intracranial stenosis and to find out more accurate criteria for intracranial stenosis using TCD. Methods : Seventy-six stroke patients were evaluated by TCD and MRA. TCD criteria for middle cerebral artery (MCA) stenosis were used by 3 methods; ≥ 80cm/sec of mean velocity(Vm), ≥ 140 cm/sec of systolic velocity(Vs), and both. For stenosis of vertebral(VA) and basilar arteries(BA), the TCD criteria followed by 2 methods; ≥ 70 cm/sec of Vm and ≥ 100 cm/sec of Vs. The stenosis of intracranial artery in MRA followed by the interpretation of specialist in the department of radiology. The sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy and kappa agreement were calculated in each criteria of TCD compared with the result of MRA. Results : The sensitivity, specificity, positive predictive value, negative predictive value, diagnostic accuracy and kappa agreement using ≥ 80cm/sec of Vm for MCA stenosis were 55.6%, 81%, 34.5%, 91.0%, 77.1%, and 0.293, respectively. Using 140 cm/sec of Vs, those were 44.4%, 92.0%, 50.5%, 90.2%, 84.7%, 0.380, and using both criteria those were 44.4%, 95.0%, 61.5%, 90.5%, 87.3%, 0.445, respectively. Those using ≥ 70 cm/sec of Vm for VA and BA stenosis were 71.4%, 93.7%, 26.3%, 99.0%, 93.0%, 0.186 and using ≥ 100 cm/sec of Vs those were 71.4%, 97.3%, 45.5%, 99.1%, 96.5%, 0.539, respectively. Conclusion : These results suggested that for the diagnosis of MCA stenosis using TCD we should use the criteria of both ≥ 80cm/sec of Vm and 140 cm/sec of Vs, and for the VA and BA stenosis we adapt the criteria of ≥ 70 cm/sec of Vm.

• Journal of Korean Neurosurgical Society
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• v.30 no.10
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• pp.1210-1219
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• 2001

Introduction : The purpose of this study was to analyze the safety, pullout strength and radiographic characteristics of unicortical and bicortical screws of cervical facet within cadaveric specimens and evaluate the influence of level of training on the positioning of these screws. Methods : Twenty-one cadavers, mean 78.9 years of age, underwent bilateral placement of 3.5mm AO lateral mass screw from C3-C6(n=168) using a slight variation of the Magerl technique. Intraoperative imaging was not used. The right side(unicortical) utilized only 14mm screws(effective length of 11mm) while on the left side to determine the length of the screw after the ventral cortex had been drilled. Three spine surgeons(attending, fellow, chief resident) with varying levels of spine training performed the procedure on seven cadavers each. All spines were harvested and lateral radiographs were taken. Individual cervical vertebrae were carefully dissected and then axial radiographs were taken. The screws were evaluated clinically and radiographically for their safety. Screws were graded clinically for their safety with respect to the spinal cord, facet joint, nerve root and vertebral artery. The grades consisted of the following categories : "satisfactory", "at risk" and "direct injury". Each screw was also graded according to its zone placement. Screw position was quantified by measuring a sagittal angle from the lateral radiograph and an axial angle from the axial radiograph. Pull-out force was determined for all screws using a material testing machine. Results : Dissection revealed that fifteen screws on the left side actually had only unicortical and not bicortical purchase as intended. The majority of screws(92.8%) were satisfactory in terms of safety. There were no injuries to the spinal cord. On the right side(unicortical), 98.9% of the screws were "satisfactory" and on the left side(bicortical) 68.1% were "satisfactory". There was a 5.8% incidence of direct arterial injury and a 17.4% incidence of direct nerve root injury with the bicortical screws. There were no "direct injuries" with the unicortical screws for the nerve root or vertebral artery. The unicortical screws had a 21.4% incidence of direct injury of the facet joint, while the bicortical screws had a 21.7% incidence. The majority of "direct injury" of bicortical screws were placed by the surgeon with the least experience. The performance of the resident surgeon was significantly different from the attending or fellow(p<0.05) in terms of safety of the nerve root and vertebral artery. The attending's performance was significantly better than the resident or fellow(p<0.05) in terms of safety of the facet joint. There was no relationship between the safety of a screw and its zone placement. The axial deviation angle measured $23.5{\pm}6.6$ degrees and $19.8{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The resident surgeon had a significantly lower angle than the attending or fellow(p<0.05). The sagittal angle measured $66.3{\pm}7.0$ degrees and $62.3{\pm}7.9$ degrees for the unicortical and bicortical screws, respectively. The attending had a significantly lower sagittal angle than the fellow or resident(p<0.05). Thirty-three screws that entered the facet joint were tested for pull-out strength but excluded from the data because they were not lateral mass screws per-se and had deviated substantially from the intended final trajectory. The mean pull-out force for all screws was $542.9{\pm}296.6N$. There was no statistically significant difference between the pull-out force for unicortical($519.9{\pm}286.9N$) and bicortical($565.2{\pm}306N$) screws. There was no significant difference in pull-out strengths with respect to zone placement. Conclusion : It is our belief that the risk associated with bicortical purchase mandates formal spine training if it is to be done safely and accurately. Unicortical screws are safer regardless of level of training. It is apparent that 14mm lateral mass screws placed in a supero-lateral trajectory in the adult cervical spine provide an equivalent strength with a much lower risk of injury than the longer bicortical screws placed in a similar orientation.

• Journal of Korean Neurosurgical Society
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• v.30 no.4
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• pp.501-508
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• 2001

Objectives : Hemifacial spasm is painless uncommon disorder characterized by involuntary paroxysmal movement on one side of face. It is known that hemifacial spasm is mainly due to pulsatile compression by vessels at the root exit zone(REZ) of the facial nerve. Microvascular decompression at REZ of the facial nerve has become the standard treatment modality for hemifacial spasm. The authors have analized patients with hemifacial spasm treated with microvascular decompression to evaluate operation result and clinical course after operation. Patients and Methods : From 1992 to 1999, 41 patients with hemifacial spasm underwent this operation. Retrospective analysis of operation results and clinical recovery patterns was done. The length of observation had been more than 6 months in all cases. Results : The ratio of male to female was 1:1.4, and age at operation ranged from 24 to 66 years. Their mean age was 47.6 years and the mean preoperative duration of symptoms was 7.2 years. Most common offending vessels were AICA in 18 cases(48%) and second most common were PICA in 13 cases(31.7%). The rest of them were 3 case in vertebral artery, and 7 cases(13%) in multiple offending vessels. Patterns of improvement after surgery could be divided into 4 clinical types. There was complete recovery in 3 days after operation in 24 cases(58.6%, Immediate complete recovery). There was complete recovery in 3 days after operation, and symptom was recurred partially, which was gradually subsided in 2 weeks after operation in 4 cases(9.8%, Delayed complete recovery type I). There was partial recovery after operation and symptom was compretely disappeared gradually in 6 months after operation in 7 cases(17.1%, Delayed complete recovery type II). Finally, there was partial recovery after operation, and symptom was somewhat remained after 6 months later(14.5%, Delayed partial recovery). Conclusion : In conclusion, microvascular decompression for hemifacial spasm is a safe and reliable treatment modality with good results of improvement and there are 4 recovery patterns in clinical course after operation in our series. Therefore, follow-up observation after microvascular decompression is necessary to evaluate the operative results and complication, especially in the delayed resolved cases.

• Journal of Korean Neurosurgical Society
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• v.42 no.4
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• pp.311-316
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• 2007

Objective : The objective of this study is to investigate the safety, surgical efficacy, and advantages of a polyaxial screw-rod system for posterior occipitocervicothoracic arthrodesis. Methods : Charts and radiographs of 32 patients who underwent posterior cervical fixation between October 2004 and February 2006 were retrospectively reviewed. Posterior cervical polyaxial screw-rod fixation was applied on the cervical spine and/or upper thoracic spine. The surgical indication was fracture or dislocation in 18, C1-2 ligamentous injury with trauma in 5, atlantoaxial instability by rheumatoid arthritis (RA) or diffuse idiopathic skeletal hyperostosis (DISH) in 4, cervical spondylosis with myelopathy in 4, and spinal metastatic tumor in 1. The patients were followed up and evaluated based on their clinical status and radiographs at 1, 3, 6 months and 1 year after surgery. Results : A total of 189 screws were implanted in 32 patients. Fixation was carried out over an average of 3.3 spinal segment (range, 2 to 7). The mean follow-up interval was 20.2 months. This system allowed for screw placement in the occiput, C1 lateral mass, C2 pars, C3-7 lateral masses, as well as the lower cervical and upper thoracic pedicles. Satisfactory bony fusion and reduction were achieved and confirmed in postoperative flexion-extension lateral radiographs and computed tomography (CT) scans in all cases. Revision surgery was required in two cases due to deep wound infection. One case needed a skin graft due to necrotic change. There was one case of kyphotic change due to adjacent segmental degeneration. There were no other complications, such as cord or vertebral artery injury, cerebrospinal fluid leak, screw malposition or back-out, or implant failure, and there were no cases of postoperative radiculopathy due to foraminal stenosis. Conclusion : Posterior cervical stabilization with a polyaxial screw-rod system is a safe and reliable technique that appears to offer several advantages over existing methods. Further biomechanical testings and clinical experiences are needed in order to determine the true benefits of this procedure.