Comparison of the effect of dexmedetomidine and midazolam under spinal anesthesia for cesarean delivery: a randomized controlled trial, single center study in South Korea

Background@#Cesarean section under spinal anesthesia may cause anxiety and hypotension. Administration of sedative drugs after delivery can diminish these side-effects, but may increase hemodynamic instability. We evaluated the effect of the administration of 0.7 μg/kg dexmedetomidine and compared it with that of 0.03 mg/kg midazolam for usefulness of sedation of the parturient after delivery during cesarean section. @*Methods@#After obtaining written consent and the ethics board approval, 60 parturients aged 20–43 years who underwent elective cesarean delivery under spinal anesthesia were recruited. A total of 0.5% hyperbaric bupivacaine (8–10 mg) and intrathecal fentanyl (10 μg) was given to induce anesthesia. Parturients were then randomly allocated to receive either midazolam (0.03 mg/kg; group M) or dexmedetomidine 0.7 (μg/kg; group D) after delivery. The primary outcome measure was patient satisfaction score. Secondary outcomes included vital signs; vasopressor dosage; incidence of shivering, nausea, and vomiting; incidence of bradycardia; time to sensory and motor recovery; postoperative nausea and vomiting score; and postoperative pain visual analog scale at 6, 24, and 48 h. @*Results@#Satisfaction scores for sedation were similar between the two groups. The systolic blood pressure, heart rate, oximetry saturation, and tympanic temperature were comparable between the two groups. The predicted mean systolic blood pressure of group D was 106.3 mmHg and that of group M was 107.5 mmHg. Both groups showed comparable adverse intraoperative and postoperative outcomes. @*Conclusions@#Dexmedetomidine and midazolam showed similar hemodynamic effects and patient satisfaction in parturients under spinal anesthesia.

Assessment of Risk Factors Affecting Refractive Outcomes after Phacovitrectomy for Epiretinal Membrane

Purpose@#To investigate factors associated with refractive outcomes after phacovitrectomy for epiretinal membrane (ERM). @*Methods@#Retrospective review of patients undergoing phacovitrectomy for ERM was done. The main outcome measure was predictive refraction error (PE), defined as observed refraction error – target refraction error, calculated by the SRK/T, Haigis, and SRK II formulae. PE was measured at postoperative 1, 3, and 6 months. Simple and multiple linear regression analysis were used to evaluate factors associated with PE. @*Results@#A total of 53 eyes of 53 patients were included. The mean PEs at postoperative 1, 3, and 6 months were all negative, implying myopic shift in all patients regardless of the intraocular lens formula used. Haigis formula showed the least myopic shift among the three formulae (p = 0.001, Friedman test). There was no significant difference in PE depending on preoperative central macular thickness (CMT) in subgroup analysis. On stepwise multiple linear regression analysis, ERM etiology (β = 0.759, p = 0.004, SRK/T formula; β = 0.733, p = 0.008, Haigis formula; β = 0.933, p < 0.001, SRK II formula), preoperative anterior chamber depth (β = –0.662, p = 0.013, Haigis formula; β = –0.747, p = 0.003, SRK II formula), and decrease of CMT (β = –0.003, p = 0.025, SRK/T formula) were significantly associated with PE at postoperative 6 months. @*Conclusions@#Myopic shift in PE was observed after combined phacovitrectomy for epiretinal membrane. ERM etiology, preoperative anterior chamber depth, and decrease of CMT were significantly associated with PE at postoperative 6 months. There was no difference in PE after surgery between the two groups defined by CMT (≥500 and <500 μm).

Intraoperative Traction May Induce Acute Onset Dysphagia With Diffuse Idiopathic Skeletal Hyperostosis After Anterior Cervical Discectomy / 대한신경손상학회지

Diffuse idiopathic skeletal hyperostosis (DISH) is a systemic bone-forming disease, and its pathogenesis remains unknown. Moreover, the incidence of DISH increases with age. DISH may be an age-related disorder that occurs more frequently in degenerative spines than in healthy spines. Most patients with DISH of the cervical spine are asymptomatic; however, mechanical compression of the esophagus by the cervical spine can induce dysphagia, hoarseness, and dyspnea. In most cases, dysphagia progresses slowly. Most cases of postoperative dysphagia after anterior cervical spine surgery occurred within 1 month, and most patients recovered spontaneously. Severe dysphagia is relatively uncommon. Here, we report a case of acute-onset dysphagia with DISH that occurred immediately after anterior cervical discectomy. We should consider the possibility of dysphagia occurring immediately after anterior cervical discectomy in patients with DISH, even in those without dysphagia before surgery. Furthermore, surgical treatment for severe postoperative dysphagia associated with DISH may be a good option.

Clinical relevance and prognostic role of preoperative cell-free single-stranded DNA concentrations in colorectal cancer patients

Purpose@#Circulating cell-free single-stranded DNA (ccf-ssDNA) is extracellular DNA and it is a useful biomarker for the diagnosis of tumors and predicting the prognosis of tumors. However, the clinical usefulness of ccf-ssDNA in colorectal cancer (CRC) is not well known. Thus, the purpose of this study was to investigate the clinical usefulness of ccf-ssDNA in CRC. @*Methods@#The study was conducted on 44 patients who had undergone surgery for CRC, and ccf-ssDNA level was measured before surgery and statistical analysis was performed on clinical factors. @*Results@#The association between ccf-ssDNA level and clinicopathological factors was analyzed and compared, and these factors included age, sex, body mass index, diabetes mellitus, hypertension, tumor markers (carcinoembryonic antigen and carbohydrate antigen 19-9), tumor location, size, stage (TNM), recurrence, and death. The group with a ccf-ssDNA level of ≥ 7.5 ng/μL had a lower age (P = 0.010), and was associated with diabetes mellitus (P = 0.037) and lymph node metastasis (P = 0.049). Multivariate analysis of disease-free survival showed that lymph node metastasis and ccf-ssDNA level (hazard ratio, 10.011; 95% confidence interval, 2.269–44.175; P = 0.002) were independent prognostic factors for recurrence. In terms of overall survival, there were no statistically significant results except for vascular invasion. @*Conclusion@#This study showed that ccf-ssDNA level in plasma in CRC patients was an independent prognostic factor that could predict recurrence non-invasively. In this regard, further evaluation with a prospective, large sample size study will be needed to obtain additional results.

Comparison of the Effectiveness of Three Lumbosacral Orthoses on Early Spine Surgery Patients: A Prospective Cohort Study

Objective@#To compare the convenience and effectiveness of the existing lumbosacral orthoses (LSO) (classic LSO and Cybertech) and a newly developed LSO (V-LSO) by analyzing postoperative data. @*Methods@#This prospective cohort study was performed from May 2019 to November 2019 and enrolled and analyzed 88 patients with degenerative lumbar spine disease scheduled for elective lumbar surgery. Three types of LSO that were provided according to the time of patient registration were applied for 6 weeks. Patients were randomized into the classic LSO group (n=31), Cybertech group (n=26), and V-LSO group (n=31). All patients were assessed using the Oswestry Disability Index (ODI) preoperatively and underwent plain lumbar radiography (anteroposterior and lateral views) 10 days postoperatively. Lumbar lordosis (LS angle) and frontal imbalance were measured with and without LSO. At the sixth postoperative week, a follow-up assessment with the ODI and orthosis questionnaire was conducted. @*Results@#No significant differences were found among the three groups in terms of the LS angle, frontal imbalance, ODI, and orthosis questionnaire results. When the change in the LS angle and frontal imbalance toward the reference value was defined as a positive change with and without LSO, the rate of positive change was significantly different in the V-LSO group (LS angle: 41.94% vs. 61.54% vs. 83.87%; p=0.003). @*Conclusion@#The newly developed LSO showed no difference regarding its effectiveness and compliance when compared with the existing LSO, but it was more effective in correcting lumbar lordosis.

Comparisons of Radiological and Clinical Characteristics between Traumatic and Non-traumatic Subdural Hematoma Patients / 대한신경손상학회지

Objective@#Subdural hematoma (SDH) primarily occurs in elderly patients. While most patients have good prognosis, some do not. Hematoma recurrence is one of the factors influencing prognosis. Moreover, some characteristic radiological factors may increase the recurrence rate. The aim of this study was to investigate whether the presence of trauma influenced radiological characteristics and hematoma recurrence in SDH patients treated with burr hole trephination. @*Methods@#From January 2012 to December 2014, we selected 83 patients diagnosed with unilateral SDH using computed tomography and/or magnetic resonance imaging. We divided the patients into 2 groups based on the presence of trauma. We compared the 2 groups with multiple parameters, such as patient factors, radiological characteristics, and recurrence rate. @*Results@#Patients who had a prolonged international normalized ratio (INR) were significantly more common in the non-traumatic SDH group (22.2%:55.2%, p=0.002). There was no statistical difference in radiological parameters between the 2 groups. The recurrence rate was marginally higher in the non-traumatic SDH group (14.8%:17.2%, p=0.502), but this difference was not statistically significant. @*Conclusion@#There were no statistically significant differences in the radiological findings, including brain atrophy, hematoma density, thickness of hematoma, and degree of midline shifting between the 2 groups. The associated trauma history may not influence recurrence. Anticoagulants medication influence INR prolongation, and commonly shown in nontraumatic group, but not statistically. INR prolongation was statistically more common in non-traumatic SDH patients than in traumatic SDH patients. INR prolongation is only a different characteristic between 2 groups.

Genotypic characterization of fluoroquinolone-resistant Escherichia coli isolates from edible offal

Abstract: Edible offal is easily contaminated by Escherichia coli (E. coli) and fluoroquinolone (FQ)-resistant E. coli is considered a serious public health problem, thus, this study investigated the genetic characteristics of FQ-resistant E. coli from edible offal. A total of 22 FQ-resistant E. coli isolates were tested. A double mutation in each gyrA and parC led the highest MIC. Four (18.2%) isolates carried plasmid-mediated quinolone resistance genes. The fimH, eaeA, escV, astA, and iucC genes were confirmed. Seventeen isolates (77.3%) were positive for plasmid replicons. The isolates showed high genetic heterogeneity based on pulsed-field gel electrophoresis patterns.

Intramuscular Hematoma on the Psoas Muscle / 대한신경손상학회지

Intramuscular hematomas on the psoas muscle are rare and usually occur as a result of trauma, iatrogenic etiology during lumbar surgery, rupture of the aortic aneurysm, and hematologic diseases. The incidence of spontaneous psoas muscle hematomas has slowly increased as a result of using anticoagulation and antiplatelet agents. Magnetic resonance (MR) imaging is a more sensitive option compared to computed tomography (CT) when diagnosing a hematoma. Coronal T2-weighted images are more useful. CT imaging is also useful to establish the rapid diagnosis of hematoma. When a prolonged prothrombin time and international normalized ratio and decrease platelet count are noted, psoas muscle hematomas should be considered, if there was no lesion in the spinal canal. Most hematomas resolve spontaneously without clinical complications if the hematoma is not large or it is not compressing the surrounding important structures, irrespective of cause.

Motor and Sensory Function as a Predictor of Respiratory Function Associated With Ventilator Weaning After High Cervical Cord Injury

OBJECTIVE: To analyze the respiratory function of high cervical cord injury according to ventilator dependence and to examine the correlations between diaphragm movement found on fluoroscopy and sensory and motor functions. METHODS: A total of 67 patients with high cervical spinal cord injury (SCI), admitted to our hospital were enrolled in the study. One rehabilitation physician performed sensory and motor examinations on all patients while each patient was in the supine position on the American Spinal Injury Association (ASIA) standard. In addition, fluoroscopic diaphragm movement studies and bedside spirometry were performed. RESULTS: Bedside spirometry and diaphragm fluoroscopic tests were analyzed according to ventilator dependence. Forced vital capacity and maximal inspiratory pressure were significantly higher in the ventilator weaned group. Natural breathing during the fluoroscopic diaphragm examinations and ventilator weaning showed statistical significance with the movement on the right, while deep breathing showed statistical significance with the movement on both sides. Deep breathing movement has correlation with the C5 key muscle. Diaphragm movement has correlation with right C3 and bilateral C4 sensory functions. CONCLUSION: The present expansion study showed that, through simple bedside physical examinations, rehabilitation physicians could relatively easily predict diaphragm movement and respiratory function recovery, which showed significance with ventilator weaning in patients with high cervical SCI.

Effect of polyphenol from Cortex Mori on melanogenesis of B16 cells and its mechanism / 中国药理学通报

Aim To investigate the inhibitory effect of polyphenol from Cortex Mori( CMP) on melanogenesis in mouse melanoma B16 cells and its possible mecha- nism. Methods Melanoma B16 cells with high ex-pression melanin were induced by α-melanocyte-stimu-lating hormone ( α-MSH) to establish cell model. Cell viability was detected by MTT assay. The melanin syn-thesis and tyrosinase activity were measured by NaOH and L-Dopa assays, respectively. The tyrosinase (TYR), tyrosinase-related protein-1 (TRP-1), tyrosi-nase-related protein-2 ( TRP-2 ) and microphthalmia associated transcription factor ( MITF ) protein and mRNA levels were measured by Western blot and qRT-PCR, respectively. Results CMP could inhibit the melanin synthesis and tyrosinase activity in α-MSH stimulated B16 cells in a dose-dependent manner ( P<0.05) . The melanin content and tyrosinase activity significantly decreased by 52.95% , 32.85% at 20 mg ·L-1of CMP, respectively. Treatment of 100 mg· L-1of arbutin reduced the melanin content and tyrosi- nase activity by 17.29% , 16.75% , respectively. Based on the results of this study, CMP showed a stronger anti-melanogenesis activity than that of positive control arbutin. After treated by CMP, the protein and mRNA levels of TYR, TRP-1, TRP-2 and MITF were significantly inhibited compared to the α-MSH group ( P<0.05) . Conclusions CMP could suppress the melanogenesis in α-MSH stimulated B16 cells, and its mechanism may be related to its regulation of the pro-tein and mRNA expressions of TYR, TRP-1, TRP-2 and MITF, and the inhibition of tyrosinase activity.

Endoscopic Resection of Xanthogranulomatous Gastritis Presenting as a Subepithelial Tumor: A Case Report

Xanthogranulomatous gastritis (XGG) presenting as a subepithelial tumor (SET) is a very rare entity. We report a case of SET-like XGG diagnosed and treated with endoscopic resection. A 55-year-old female patient was initially referred with a 1.5-cm SET located at the anterior wall of the middle antrum. Endoscopic ultrasound examination revealed submucosal invasion without any perigastric lymph node enlargement. Endoscopic resection was performed for an accurate diagnosis and treatment, and the lesion was diagnosed histopathologically as XGG. At the 18-month follow-up after endoscopic resection, there was no evidence of XGG recurrence. SET-like XGG is very rare and the diagnosis is a preoperative challenge. However, inflammatory tumors should be considered in the differential diagnosis of SET

Amount of Weight-Bearing During Tilt Table Inclination, With Neutral and Unilateral Knee Flexion Postures

OBJECTIVE: To analyze the amount of weight-bearing during tilt table increments, with a review of neutral and unilateral knee flexion postures. METHODS: There were 17 healthy participants enrolled in this study. The subjects were tilted from 10° to 90°, and their body weight was measured at each 10° increment. In the first test, both plantar pressures, with the subjects in neutral posture, were recorded. During the second and third tests, the angle of inclination was thus recorded and increased, with the subjects in unilateral knee flexion posture; flexion was maintained at 25° by attaching a cylindrical support to the tilt table at the level of the popliteal fossa. RESULTS: The study was divided into two types of postures: neutral and unilateral knee flexion. The percentage of body weight (%BW) between each leg during neutral posture was noted as not being statistically significant. The %BW of one side during tilt table inclination was significantly different between the two postures at 10° to 80° (p < 0.05). The weight during unilateral knee flexion posture was lower as analyzed, regardless of tilt table inclination compared with that in neutral posture. We note that fifty percent of the ratio of %BW was noted at 33.12° and 38.76° in neutral and flexion postures, respectively. CONCLUSION: The unilateral knee flexion could induce the effect of decreased body weight compared with non-flexion side. The results of this study will help in setting a safe and quantitative percentage of weight-bearing on the lower extremity during tilt training.

Successful Management of Acquired Tracheomalacia of Patients With Amyotrophic Lateral Sclerosis: A Report of Three Cases

Tracheomalacia is characterized by weakness of the tracheal walls and supporting cartilage. It results in dynamic compression of the airway, where the cross-sectional area of the trachea is reduced by expiratory compression. Acquired tracheomalacia results from complications associated with the use of endotracheal or tracheostomy tubes. In this report, we present three cases of patients with amyotrophic lateral sclerosis (ALS) successfully treated for tracheomalacia, including one case where the patient underwent surgery for combined tracheoesophageal fistula. We discuss the appropriate management strategies for tracheomalacia in patients with ALS. Through these case reports, we note the results of ALS patients who will have tracheostomy, and who are therefore at risk of sustaining a long term high cuff pressure, this study provides an evaluation for tracheomalacia and therapeutic management which should be considered for improving patient care outcomes.

Effects on Periocular Tissues after Proton Beam Radiation Therapy for Intraocular Tumors

BACKGROUND: To present our experience on orbital and periorbital tissue changes after proton beam radiation therapy (PBRT) in patients with intraocular tumors, apart from treatment outcomes and disease control. METHODS: Medical records of 6 patients with intraocular tumors who had been treated with PBRT and referred to oculoplasty clinics of two medical centers (Seoul National University Hospital and Seoul Metropolitan Government-Seoul National University Boramae Medical Center) from October 2007 to September 2014 were retrospectively reviewed. The types of adverse effects associated with PBRT, their management, and progression were analyzed. In anophthalmic patients who eventually underwent enucleation after PBRT due to disease progression, orbital volume (OV) was assessed from magnetic resonance (MR) images using the Pinnacle3 program. RESULTS: Among the six patients with PBRT history, three had uveal melanoma, and three children had retinoblastoma. Two eyes were treated with PBRT only, while the other four eyes ultimately underwent enucleation. Two eyes with PBRT only suffered from radiation dermatitis and intractable epiphora due to canaliculitis or punctal obstruction. All four anophthalmic patients showed severe enophthalmic features with periorbital hollowness. OV analysis showed that the difference between both orbits was less than 0.1 cm before enucleation, but increased to more than 2 cm3 after enucleation. CONCLUSION: PBRT for intraocular tumors can induce various orbital and periorbital tissue changes. More specifically, when enucleation is performed after PBRT due to disease progression, significant enophthalmos and OV decrease can develop and can cause poor facial cosmesis as treatment sequelae.

Clinical Outcomes of Proton Beam Therapy for Choroidal Melanoma at a Single Institute in Korea / Journal of the Korean Cancer Association, 대한암학회지

PURPOSE: This study retrospectively evaluated the clinical outcomes and complications of proton beam therapy (PBT) in a single institution in Korea and quantitatively analyzed the change in tumor volume after PBT using magnetic resonance imaging (MRI). MATERIALS AND METHODS: Twenty-four treatment-naïve patients who underwent PBT for choroidal melanoma between 2009 and 2015 were reviewed. Dose fractionation was 60-70 cobalt gray equivalents over 5 fractions. Orbital MRIs were taken at baseline and 3, 6, and 12 months after PBT and annually thereafter. The tumor volume was reconstructed and evaluated by stacking the tumor boundary in each thin-sliced axial T1-weighted image using MIM software. RESULTS: The median follow-up duration was 36.5 months (range, 9 to 82 months). One patient had suspicious local progression and two patients had distant metastasis. The 3-year local progression-free survival, distant metastasis-free survival, and overall survival rates were 95.8%, 95.8%, and 100%,respectively. Five Common Terminology Criteria for Adverse Event ver. 4.03 grade 3-4 toxicities were observed in four patients (16.7%), including one with neovascular glaucoma. The mean tumor volume at the baseline MRI was 0.565±0.084 mL (range, 0.074 to 1.610 mL), and the ratios of the mean volume at 3, 6, and 12 months to that at baseline were 81.8%, 67.3%, and 60.4%, respectively. CONCLUSION: The local controlrate and complication profile after PBT in patientswith choroidal melanoma in Korea were comparable with those reported in a previous PBT series. The change in tumor volume after PBT exhibited a gradual regression pattern on MRI.

Ctbp2-mediated β-catenin regulation is required for exit from pluripotency

The canonical Wnt pathway is critical for embryonic stem cell (ESC) pluripotency and aberrant control of β-catenin leads to failure of exit from pluripotency and lineage commitments. Hence, maintaining the appropriate level of β-catenin is important for the decision to commit to the appropriate lineage. However, how β-catenin links to core transcription factors in ESCs remains elusive. C-terminal-binding protein (CtBP) in Drosophila is essential for Wnt-mediated target gene expression. In addition, Ctbp acts as an antagonist of β-catenin/TCF activation in mammals. Recently, Ctbp2, a core Oct4-binding protein in ESCs, has been reported to play a key role in ESC pluripotency. However, the significance of the connection between Ctbp2 and β-catenin with regard to ESC pluripotency remains elusive. Here, we demonstrate that C-terminal-binding protein 2 (Ctbp2) associates with major components of the β-catenin destruction complex and limits the accessibility of β-catenin to core transcription factors in undifferentiated ESCs. Ctbp2 knockdown leads to stabilization of β-catenin, which then interacts with core pluripotency-maintaining factors that are occupied by Ctbp2, leading to incomplete exit from pluripotency. These findings suggest a suppressive function for Ctbp2 in reducing the protein level of β-catenin, along with priming its position on core pluripotency genes to hinder β-catenin deposition, which is central to commitment to the appropriate lineage.

Angiolipoma on the Lumbar Spine

Angiolipomas are composed of mature adipose tissue and blood vessels. Spinal angiolipomas are rare benign tumors with a good prognosis, and most symptoms are due to progressive compression of the spinal cord and root. The treatment of choice is total resection without any additional therapy. We report a case of an epidural angiolipoma on the lumbar spine in a 69-year-old man with weakness of the lower extremities. Lumbar magnetic resonance images revealed a well-enhanced epidural mass. He underwent laminectomy, and the tumor was completely removed. Pathologic examination confirmed the tumor was an angiolipoma. The patient’s symptoms gradually improved postoperatively.

Iron Contents in Rice Food Derived from the Iron Pot, and In Vitro Study Regarding Heme Oxygenase-1 Activity / 임상소아혈액종양

BACKGROUND: Iron pots have long been used for cooking in several countries. Early studies have shown that the use of such iron pots can increase the iron content of food cooked in them and that this increased iron content has some effect on iron uptake. This study was designed to evaluate the iron content in rice cooked in a traditional iron pot and study the iron uptake by macrophages through heme oxygenase-1 (HO-1).METHODS: The iron pot used in this study was round-shaped and had no legs. The iron content of rice cooked in the iron pot was measured. Thereafter, the bioavailability of iron was measured using western blot analysis.RESULTS: A total of 35 samples were analyzed for iron concentrations, which were 10.94±18.08 mg/L (range: 0.18–56.53 mg/L). The biochemical activity in most of materials was 1.5–9 times that of the activity observed in the control group.CONCLUSION: The iron concentration of rice cooked in iron pots were found to be relatively high. The introduction of iron pots in routine cooking practices may be a promising way of increasing the supply of iron, especially for people with severe iron deficiency anemia. Further, increased activity of HO-1, induced by supplementation of iron from the cast iron, may help in maintaining iron homeostasis.

Iron Contents in Rice Food Derived from the Iron Pot, and In Vitro Study Regarding Heme Oxygenase-1 Activity / 임상소아혈액종양

BACKGROUND: Iron pots have long been used for cooking in several countries. Early studies have shown that the use of such iron pots can increase the iron content of food cooked in them and that this increased iron content has some effect on iron uptake. This study was designed to evaluate the iron content in rice cooked in a traditional iron pot and study the iron uptake by macrophages through heme oxygenase-1 (HO-1). METHODS: The iron pot used in this study was round-shaped and had no legs. The iron content of rice cooked in the iron pot was measured. Thereafter, the bioavailability of iron was measured using western blot analysis. RESULTS: A total of 35 samples were analyzed for iron concentrations, which were 10.94±18.08 mg/L (range: 0.18–56.53 mg/L). The biochemical activity in most of materials was 1.5–9 times that of the activity observed in the control group. CONCLUSION: The iron concentration of rice cooked in iron pots were found to be relatively high. The introduction of iron pots in routine cooking practices may be a promising way of increasing the supply of iron, especially for people with severe iron deficiency anemia. Further, increased activity of HO-1, induced by supplementation of iron from the cast iron, may help in maintaining iron homeostasis.

Effectiveness of Intraluminal Air Decompression on Postcolonoscopic Pain According to Reinsertion Site / 가정의학회지

BACKGROUND: Colonoscopy is a very effective and essential examination to diagnose colorectal cancer; however, many patients experience discomfort due to post-examination abdominal pain, which reduces colonoscopy compliance. This study was conducted to determine methods for reducing post-colonoscopic abdominal pain. METHODS: We conducted a randomized controlled study of 405 male and female adults who visited Hana General Hospital in Cheongju. We surveyed general characteristics, history of colonoscopy, and other related factors, then categorized examinees into 5 groups (0-5) according to the site of scope reinsertion. Pain was measured using a numeric rating scale (NRS). RESULTS: The mean age of examinees in this study was 47.8 years, and 210 participants had prior experience of colonoscopy. No significant difference was observed between variables, with the exception of reinsertion duration (P=0.005). Pain scores were different between performing physicians (P=0.006), and were higher when the subjective level of procedure difficulty was low (P=0.026) in univariate analysis. Pain scores decreased as the reinsertion site became closer to the proximal colon (P<0.001), but there was no significant difference between groups 3 and 4. The results of multiple logistic regression analysis, including univariate analysis, showed that group 1 had 0.48 times, group 2 had 0.38 times, group 3 had 0.09 times, and group 4 had 0.03 times odds ratio (moderate-to-severe pain, NRS ≥4) than control group 0. CONCLUSION: Air decompression by scope reinsertion is an effective way to reduce abdominal pain after colonoscopy. Removing air when the reinserted scope approaches the hepatic flexure seems to be the most effective method to reduce post-colonoscopic pain.