Dorsal Epidural Gas after Lumbar Microdiskectomy Treated with CT-guided Needle Aspiration / 대한신경손상학회지

To present a case of unusual dorsal epidural gas (EG) accumulation after a simple lumbar microdiskectomy (MD), treated with computed tomography (CT)-guided needle aspiration.A 78-year-old woman underwent simple lumbar MD at the L3–4 level. One week after the operation, the patient complained of severe back pain radiating to the right thigh. Follow-up magnetic resonance imaging (MRI) and CT revealed huge EG formation at the dorsal L3–4 epidural space. Conservative treatment did not resolve the patient's pain. We performed CT-guided needle aspiration after 1 week of conservative treatment. The patient's pain fully resolved after aspiration, but it recurred 1 week later. Follow-up MRI and CT revealed reaccumulation of the dorsal EG at the L3–4 level. CT-guided needle aspiration was repeated, again leading to full pain resolution. Follow-up CT 6 months after the second aspiration showed no recurrent dorsal EG. The patient has been symptom-free for 1 year since the second aspiration. CT-guided needle aspiration is a safe and effective alternative to reoperation in the context of dorsal EG formation after MD.

Effect of palmitoylethanolamide on inflammatory and neuropathic pain in rats / 대한마취과학회지

BACKGROUND: A growing body of evidence suggests that neuroinflammation, which is characterized by infiltration of immune cells, activation of mast cells and glial cells, and production of inflammatory mediators in the peripheral and central nervous systems, plays an important role in the induction and maintenance of chronic pain. Palmitoylethanolamide (PEA), which is a type of N-acylethanolamide and a lipid, has an anti-inflammatory effect. Relative to the anti-inflammatory effect, little is known about its analgesic effect in chronic pain. This study aimed to determine whether PEA relieves chronic inflammatory and neuropathic pain. METHODS: Male Sprague-Dawley rats were injured by transection of the left L5 and L6 spinal nerves to induce neuropathic pain or were injected with monoiodoacetic acid into the synovial cavity of knee joints to induce inflammatory pain. To assess the degree of pain, two kinds of stimuli - pressing von Frey filaments and wetting with acetone - were applied to the plantar surface of the rat to measure mechanical and cold sensitivity, respectively. Pain was measured by assessing behavioral responses, including paw withdrawal response threshold and paw withdrawal frequency upon stimulation. RESULTS: Neuropathic pain caused by spinal nerve transection (SNT) decreased the mechanical threshold and increased the frequency of response to acetone application. But, cold allodynia caused by SNT did not decrease the withdrawal frequency. Mechanical hyperalgesia caused by chronic inflammation was significantly reduced by both intraperitoneal and intra-articular injections of PEA. CONCLUSIONS: These outcomes revealed that PEA might be effective in relieving inflammatory and neuropathic pain, especially pain induced by mechanical hyperalgesia, but not cold allodynia.

Influence of acute normovolemic hemodilution on the potency and time course of action of rocuronium in rabbits

BACKGROUND: We performed this study to evaluate the potency and time course of rocuronium-induced neuromuscular block following moderate or severe acute normovolemic hemodilution (ANH) in rabbits. METHODS: Forty five rabbits were randomly assigned to the control (C) group, the moderate ANH (M) group, or the severe ANH (S) group. After stabilization of sevoflurane anesthesia, ANH was achieved by drainage of arterial blood and an intravenous infusion of 6% hydroxyethyl starch, during which hematocrit (Hct) decreased to 26.2 ± 2.5% in the M group and 17.6 ± 2.2% in the S group. We determined dose-response relationships of rocuronium in the three groups and created a time course of the action of 0.6 mg/kg rocuronium. RESULTS: The 50% effective dose (ED50) for rocuronium was 45% and 50% lower in the M and S groups, respectively, than in the C group (50.9 ± 6.3 µg/kg) (P < 0.001). The onset time after 0.6 mg/kg rocuronium was faster in the ANH groups compared with the C group (P < 0.001). The duration of neuromuscular block was prolonged by 38% and 43% in the M and S groups, respectively, compared with the C group (49.1 ± 6.9 min) (P < 0.001). CONCLUSIONS: ANH resulted in high potency, rapid onset, and prolonged duration of rocuronium. However, the severity of ANH did not alter the potency and duration of action of rocuronium.

Primary Aortoenteric Fistula to the Sigmoid Colon in Association with Intra-abdominal Abscess / 대한소화기학회지

Primary aortoenteric fistula (PAEF) is a rare but catastrophic cause of massive gastrointestinal bleeding. Diagnosis of PAEF is difficult to make and is frequently delayed without strong clinical suspicion. Timely surgical intervention is essential for patient's survival. We report on a case of an 86-year-old woman with no history of abdominal surgery, who presented with abdominal pain. Initially, computed tomography scan showed an intra-abdominal abscess, located anterior to the aortic bifurcation. However, she was discharged without treatment because of spontaneous improvement on a follow-up computed tomography scan, which showed a newly developed right common iliac artery aneurysm. One week later, she was readmitted due to recurrent abdominal pain. On the second day of admission, sudden onset of gastrointestinal bleeding occurred for the first time. After several endoscopic examinations, an aortoenteric fistula bleeding site was found in the sigmoid colon, and aortography showed progression of a right common iliac artery aneurysm. We finally concluded that intra-abdominal abscess induced an infected aortic aneurysm and enteric fistula to the sigmoid colon. This case demonstrated an extremely rare type of PAEF to the sigmoid colon caused by an infected abdominal aortic aneurysm, which has rarely been reported.

Very Early Onset of Amiodarone-Induced Pulmonary Toxicity

Amiodarone is a widely used antiarrhythmic agent. Among its various adverse effects, amiodarone-induced pulmonary toxicity (APT) is the most life threatening complication, which has been described mostly in patients who have been in treatment with high accumulative doses for a long duration of time. However, amiodarone therapy in short-term duration induced APT was rarely reported. We describe a case of a 54-year-old man who is presented with symptoms of APT after a few days of therapy for post-myocardial infarction ventricular tachycardia. For early diagnosis and successful treatment, awareness and high suspicion of this rare type of early onset APT is crucial in patients with amiodarone therapy.

Histochemical study of lectin-binding patterns in the rat vomeronasal organ during postnatal development / 대한수의학회지

Histochemical patterns of lectin binding during development of the rat vomeronasal organ (VNO) were studied to determine whether glycoconjugates are differently expressed after birth. Three types of lectins, Dolichos biflorus agglutinin (DBA), wheat germ agglutinin (WGA), and Ulex europaeus agglutinin I (UEA-I), were studied histochemically in the rat VNO at various stages post-birth: postnatal days 1 and 7, the preweaning period (4 weeks after birth), and at sexual maturity (8 weeks after birth). The free border of the vomeronasal sensory epithelium was positive for both WGA and UEA-I in rats of all ages; whereas, VNO receptor cells and supporting cells were positive only for both WGA and UEA-I from 4 weeks after birth. DBA reactivity was detected in the free border but less so in receptor cells and supporting cells. WGA and UEA-I, but not DBA, showed similar patterns in various ages. In the Jacobson's gland, WGA, UEA-I and DBA were detected in some acini from 4 weeks after birth but not at postnatal days 1 or 7. Collectively, reactivity for three lectins, WGA, UEA-I and DBA, increased in receptor cells and gland acini during postnatal development, possibly contributing to the enhanced chemoreception in rats.

Quantitative Assessment Technology of Small Animal Myocardial Infarction PET Image Using Gaussian Mixture Model / 의학물리

Nuclear medicine images (SPECT, PET) were widely used tool for assessment of myocardial viability and perfusion. However it had difficult to define accurate myocardial infarct region. The purpose of this study was to investigate methodological approach for automatic measurement of rat myocardial infarct size using polar map with adaptive threshold. Rat myocardial infarction model was induced by ligation of the left circumflex artery. PET images were obtained after intravenous injection of 37 MBq 18F-FDG. After 60 min uptake, each animal was scanned for 20 min with ECG gating. PET data were reconstructed using ordered subset expectation maximization (OSEM) 2D. To automatically make the myocardial contour and generate polar map, we used QGS software (Cedars-Sinai Medical Center). The reference infarct size was defined by infarction area percentage of the total left myocardium using TTC staining. We used three threshold methods (predefined threshold, Otsu and Multi Gaussian mixture model; MGMM). Predefined threshold method was commonly used in other studies. We applied threshold value form 10% to 90% in step of 10%. Otsu algorithm calculated threshold with the maximum between class variance. MGMM method estimated the distribution of image intensity using multiple Gaussian mixture models (MGMM2, em leader MGMM5) and calculated adaptive threshold. The infarct size in polar map was calculated as the percentage of lower threshold area in polar map from the total polar map area. The measured infarct size using different threshold methods was evaluated by comparison with reference infarct size. The mean difference between with polar map defect size by predefined thresholds (20%, 30%, and 40%) and reference infarct size were 7.04+/-3.44%, 3.87+/-2.09% and 2.15+/-2.07%, respectively. Otsu verse reference infarct size was 3.56+/-4.16%. MGMM methods verse reference infarct size was 2.29+/-1.94%. The predefined threshold (30%) showed the smallest mean difference with reference infarct size. However, MGMM was more accurate than predefined threshold in under 10% reference infarct size case (MGMM: 0.006%, predefined threshold: 0.59%). In this study, we was to evaluate myocardial infarct size in polar map using multiple Gaussian mixture model. MGMM method was provide adaptive threshold in each subject and will be a useful for automatic measurement of infarct size.

Feasibility of an Ultrasonographic Categorical Reporting System for Thyroid Incidentaloma

PURPOSE: To evaluate the feasibility of an ultrasonographic category system for the proper management of incidentally found thyroid nodules. MATERIALS and METHODS: We retrospectively evaluated 2,688 patients who had thyroid nodules and underwent ultrasonography-guided fine needle aspiration biopsy. We made an ultrasonographic categorical reporting system by logistic regression analysis for comparison with the pathologic results of cytology and biopsy. RESULTS: The distribution of malignancy probability for benign nodules was 0.07 to 0.23 and for malignant nodules was 0.37 to 0.91 (95% confidence intervals). We stratified the distribution of the probability of malignancy of each nodule into 6 categories (category 0, no nodule; 1, highly suggestive of benignancy; 2, probably benign; 3, indeterminate; 4, probably malignant; and 5, highly suggestive of malignancy) and summarized the representative US findings. We compared the category of each nodule with the pathological results. In nodules with surgically proven pathologic diagnoses, benign lesions were 96.1% (348/361) in category 1 and malignant lesions were 98.6% (139/141) in category 5. CONCLUSION: We suggest that the ultrasonographic category system for thyroid incidentaloma may provide optimal strategies to manage incidentally found thyroid nodules.