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Background@#Ultrasound-guided first sacral transforaminal epidural steroid injection (S1 TFESI) is a useful and easily applicable alternative to fluoroscopy or computed tomography (CT) in lumbosacral radiculopathy. When a needle approach is used, poor visualization of the needle tip reduces the accuracy of the procedure, increasing its difficulty. This study aimed to improve ultrasound-guided S1 TFESI by evaluating radiological S1 posterior foramen data obtained using three-dimensional CT (3D-CT). @*Methods@#Axial 3D-CT images of the pelvis were retrospectively analyzed. The radiological measurements obtained from the images included 1st posterior sacral foramen depth (S1D, mm), 1st posterior sacral foramen width (S1W, mm), the angle of the 1st posterior sacral foramen (S1A, °), and 1st posterior sacral foramen distance (S1ds, mm). The relationship between the demographic factors and measured values were then analyzed. @*Results@#A total of 632 patients (287 male and 345 female) were examined. The mean S1D values for males and females were 11.9 ± 1.9 mm and 10.6 ± 1.8 mm, respectively (P < 0.001); the mean S1A 28.2 ± 4.8° and 30.1 ± 4.9°, respectively (P < 0.001); and the mean S1ds, 24.1 ± 2.9 mm and 22.9 ± 2.6 mm, respectively (P < 0.001); however, the mean S1W values were not significantly different. Height was the only significant predictor of S1D (β =0.318, P = 0.004). @*Conclusions@#Ultrasound-guided S1 TFESI performance and safety may be improved with adjustment of needle insertion depth congruent with the patient’s height.
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Background@#Ultrasound-guided caudal epidural injection (CEI) is limited in that it cannot confirm drug distribution at the target site without fluoroscopy. We hypothesized that visualization of solution flow through the inter-laminar space of the lumbosacral spine using color Doppler ultrasound alone would allow for confirmation of drug distribution. Therefore, we aimed to prospectively evaluate the usefulness of this method by comparing the color Doppler image in the paramedian sagittal oblique view of the lumbosacral spine (LS-PSOV) with the distribution of the contrast medium observed during fluoroscopy. @*Methods@#Sixty-five patients received a 10-mL CEI of solution containing contrast medium under ultrasound guidance. During injection, flow was observed in the LSPSOV using color Doppler ultrasonography, following which it was confirmed using fluoroscopy. The presence of contrast image at L5-S1 on fluoroscopy was defined as “successful CEI.” We then calculated prediction accuracy for successful CEI using color Doppler ultrasonography in the LS-PSOV. We also investigated the correlation between the distribution levels measured via color Doppler and fluoroscopy. @*Results@#Prediction accuracy with color Doppler ultrasonography was 96.9%. The sensitivity, specificity, positive predictive value, and negative predictive value were 96.7%, 100%, 100%, and 60.0%, respectively. In 52 of 65 patients (80%), the highest level at which contrast image was observed was the same for both color Doppler ultrasonography and fluoroscopy. @*Conclusions@#Our findings demonstrate that color Doppler ultrasonography in the LS-PSOV is a new method for determining whether a drug solution reaches the lumbosacral region (i.e., the main target level) without the need for fluoroscopy.
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Background@#Ultrasound-guided caudal epidural injection (CEI) is limited in that it cannot confirm drug distribution at the target site without fluoroscopy. We hypothesized that visualization of solution flow through the inter-laminar space of the lumbosacral spine using color Doppler ultrasound alone would allow for confirmation of drug distribution. Therefore, we aimed to prospectively evaluate the usefulness of this method by comparing the color Doppler image in the paramedian sagittal oblique view of the lumbosacral spine (LS-PSOV) with the distribution of the contrast medium observed during fluoroscopy. @*Methods@#Sixty-five patients received a 10-mL CEI of solution containing contrast medium under ultrasound guidance. During injection, flow was observed in the LSPSOV using color Doppler ultrasonography, following which it was confirmed using fluoroscopy. The presence of contrast image at L5-S1 on fluoroscopy was defined as “successful CEI.” We then calculated prediction accuracy for successful CEI using color Doppler ultrasonography in the LS-PSOV. We also investigated the correlation between the distribution levels measured via color Doppler and fluoroscopy. @*Results@#Prediction accuracy with color Doppler ultrasonography was 96.9%. The sensitivity, specificity, positive predictive value, and negative predictive value were 96.7%, 100%, 100%, and 60.0%, respectively. In 52 of 65 patients (80%), the highest level at which contrast image was observed was the same for both color Doppler ultrasonography and fluoroscopy. @*Conclusions@#Our findings demonstrate that color Doppler ultrasonography in the LS-PSOV is a new method for determining whether a drug solution reaches the lumbosacral region (i.e., the main target level) without the need for fluoroscopy.
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Background@#Errors in counting spinal segments are common during interventional procedures when there are transitional vertebrae. In this study, we investigated the prevalence of the transitional vertebrae including thoracolumbar transitional vertebra (TLTV) and lumbosacral transitional vertebrae (LSTV). The relationship between the existence of TLTV and abnormal rib count or the existence of LSTV were also evaluated. @*Methods@#The vertebral levels were counted craniocaudally, starting from C1, based on the assumption of 7 cervical, 12 thoracic, and 5 lumbar vertebrae, using whole spine spiral three-dimensional computed tomographic images. The 20th and 25th vertebrae were defined as L1 and S1, respectively. @*Results@#In total, 150 patients had TLTV, with a prevalence of 11.2% (150/1,340). LSTV was observed in 111 of 1,340 cases (8.3%). Sacralization was observed in 68 of 1,340 cases (5.1%) and lumbarization in 43 of 1,340 cases (3.2%). There was a significant relationship between the existence of TLTV and the abnormal rib count (odds ratio [OR]: 117.26, 95% confidence interval [95% CI]: 60.77–226.27; P < 0.001) and LSTV (OR: 7.38, 95% CI: 3.99–13.63; P < 0.001). @*Conclusions@#Our study results suggest that patients with TLTV are more likely to have an abnormal rib count or LSTV. If a TLTV or LSTV is seen on the fluoroscopic image, a whole spine image is necessary to permit accurate numbering of the lumbar vertebra.
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BACKGROUND: For patients who have back pain or radiating pain, lumbar intervention should be performed at the correct lumbar segment that triggers pain. It is quite common for pain physicians to identify lumbar segments based upon the 12th pair of ribs to do an interventional procedure. CASE: We experienced two cases of rib number abnormality (absent 12th rib pair) that made the injection ineffective. In both cases, we had misidentified the lumbar segmentation due to rib abnormality. Although the procedure was performed properly, the clinical symptoms of the patient were not well correlated with the dermatome, and the diagnosis was delayed. CONCLUSIONS: These cases suggest that rib counting is necessary for more accurate lumbar segmentation. If the expected effect has not appeared after intervention, rib numbers should be checked.
Subject(s)
Humans , Back Pain , Diagnosis , Fluoroscopy , Lumbar Vertebrae , RibsABSTRACT
BACKGROUND: Several nerve blocks can reduce the incidence of postherpetic neuralgia (PHN) as well as relieve acute zoster-related pain, but the long-term outcome of PHN has not been clearly determined. This study investigated the efficacy of selective nerve root block (SNRB) for herpes zoster (HZ) on the long-term outcome of PHN. METHODS: We prospectively conducted an interview of patients who had undergone an SNRB for HZ from January 2006 to December 2016 to evaluate their long-term PHN status. The relationship between the time from HZ onset to the first SNRB and the long-term outcome of PHN was investigated. RESULTS: The data of 67 patients were collected. The patients were allocated to acute (SNRB ≤ 14 days, n = 16) or subacute (SNRB > 14 days, n = 51) groups. The proportions of cured patients were 62.5% and 25.5% in the acute and subacute groups (P = 0.007), respectively. In logistic regression, an SNRB >14 days was the significant predictor of PHN (adjusted odd ratio, 3.89; 95% confidence interval, 1.02–14.93; P = 0.047). Kaplan–Meier analysis revealed that time from the SNRB to the cure of PHN was significantly shorter in the acute group (2.4 ± 0.7 yr) than in the subacute group (5.0 ± 0.4 yr; P = 0.003). CONCLUSIONS: An early SNRB during the acute stage of HZ (within 14 days) appears to decrease the incidence and shorten the duration of PHN, with a median of 5.0 years of follow-up.
Subject(s)
Humans , Follow-Up Studies , Ganglia, Spinal , Herpes Zoster , Incidence , Logistic Models , Nerve Block , Neuralgia, Postherpetic , Prospective StudiesABSTRACT
BACKGROUND: The Quality of Recovery-40 (QoR-40) is a widely-used, self-rated, and self-completed questionnaire for postoperative patients. The questionnaire is intended to elicit information from each patient regarding the quality of recovery during the postoperative period. It is noteworthy, however, that an official Korean version of the QoR-40 (QoR-40K) has not been established. The purpose of this study was to develop the QoR-40K by translation and cultural adaptation process and to evaluate the validity and reliability of the QoR-40K. METHODS: After pre-authorization from the original author of the QoR-40, the translation procedure was established and carried out based upon Beaton’s recommendation to create a QoR-40K model comparable to the original English QoR-40. Two hundred surgical patients were enrolled, and each completed the questionnaire during the preoperative period, on the third day, and 1 month after surgery. The QoR-40K was compared with the visual analogue scale (VAS) and another health-related questionnaire, the Short-form Health Survery-36 (SF-36). The method of validation for QoR-40K included test-retest reliability, internal consistency, and level of responsiveness. RESULTS: Spearman’s correlation coefficient for test-retest reliability was 0.895 (P < 0.001), and Cronbach’s alpha of the global QoR-40K on the third day after surgery was 0.956. A positive correlation was obtained between the QoR-40K and the mental component summary of SF-36 (ρ = 0.474, P < 0.001), and a negative correlation was observed between QoR-40K and VAS (ρ = −0.341, P < 0.001). The standardized responsive mean of the total QoR-40K was 0.71. CONCLUSIONS: The QoR-40K was found to be as acceptable and reliable as the original English QoR-40 for Korean patients after surgery, despite the apparent differences in the respective patients’ cultural backgrounds.
Subject(s)
Humans , Cross-Cultural Comparison , Methods , Postoperative Period , Preoperative Period , Quality of Life , Reproducibility of ResultsABSTRACT
BACKGROUND: The intraarticular (IA) injection has become popular for the management of the osteoarthritic knee without an effusion. The success rate of IA injection would be better if it was able to be visually confirmed. We hypothesized that an anterolateral approach, which targets the synovial membrane of the lateral condyle using ultrasound, would provide an equivalent alternative to the anterolateral approach, targeting the synovial membrane of the medial condyle for IA injection of the knee. METHODS: A total of 96 knees with osteoarthritis were randomized placed into the two groups, which were group I (anterolateral approach to the medial condyle) and group II (anterolateral approach to the lateral condyle). The primary outcome was to compare the success rate of the two methods of IA injection. The required length of the needle for injection was also measured and compared. Pain intensity was assessed using the Numeric Rating Scale in order to evaluate the success of injection. RESULTS: There were no significant differences in the success rate between both groups. The success rate of group I and group II were 87.8% (95%, CI 78.7–97.0) and 91.5% (95%, CI 83.6–99.5), respectively (P = 0.549). The needle depth was 5.0 ± 0.8 (3.0 to 6.1 cm) in group I, and 3.0 ± 0.8 (1.5 to 5 cm) in group II (P < 0.001). CONCLUSIONS: The anterolateral approach to the lateral femoral condyle, using ultrasound, is an alternative method to the approach targeting the medial femoral condyle, using shorter needle.
Subject(s)
Humans , Epiphyses , Injections, Intra-Articular , Knee Joint , Knee , Methods , Needles , Osteoarthritis , Synovial Membrane , UltrasonographyABSTRACT
BACKGROUND: Dopamine is an inotropic agent that is often selected for continuous infusion. For hemodynamic stability, the rate of infusion is controlled in the range of 5-15 µg/kg/min. This study aimed to compare the time intervals from the administration of dopamine to the onset of its hemodynamic effects when dopamine was administered through three different peripheral veins (the cephalic vein [CV], the great saphenous vein [GSV], and the external jugular vein [EJV]). METHODS: Patients in group 1, group 2, and group 3 received dopamine infusions in the CV, GSV, and EJV, respectively. A noninvasive continuous cardiac output monitor (NICCOMO™, Medis, Ilmenau, Germany) was used to assess cardiac output (CO) and systemic vascular resistance (SVR). Six minutes after intubation, baseline heart rate (HR), systolic blood pressure (BP), diastolic BP, mean arterial pressure (MAP), CO, and SVR values were recorded and dopamine infusion was initiated at a dose of 10 µg/kg/min. Hemodynamic changes at 0, 4, 8, 12, and 15 minutes postinfusion were recorded. RESULTS: No statistically significant differences were observed among the three groups with respect to the rate of hemodynamic change. In all groups, systolic BP, diastolic BP, MAP, and SVR tended to increase after decreasing for the first 4 minutes; in contrast, HR and CO decreased until 8 minutes, after which they tended to reach a plateau. CONCLUSIONS: For patients under general anesthesia receiving dopamine at 10 µg/kg/min, there were no clinical differences in the effect of dopamine administered through three different peripheral veins.
Subject(s)
Humans , Anesthesia, General , Arterial Pressure , Blood Pressure , Cardiac Output , Dopamine , Heart Rate , Hemodynamics , Intubation , Jugular Veins , Saphenous Vein , Vascular Resistance , VeinsABSTRACT
BACKGROUND: Dopamine is an inotropic agent that is often selected for continuous infusion. For hemodynamic stability, the rate of infusion is controlled in the range of 5-15 µg/kg/min. This study aimed to compare the time intervals from the administration of dopamine to the onset of its hemodynamic effects when dopamine was administered through three different peripheral veins (the cephalic vein [CV], the great saphenous vein [GSV], and the external jugular vein [EJV]). METHODS: Patients in group 1, group 2, and group 3 received dopamine infusions in the CV, GSV, and EJV, respectively. A noninvasive continuous cardiac output monitor (NICCOMO™, Medis, Ilmenau, Germany) was used to assess cardiac output (CO) and systemic vascular resistance (SVR). Six minutes after intubation, baseline heart rate (HR), systolic blood pressure (BP), diastolic BP, mean arterial pressure (MAP), CO, and SVR values were recorded and dopamine infusion was initiated at a dose of 10 µg/kg/min. Hemodynamic changes at 0, 4, 8, 12, and 15 minutes postinfusion were recorded. RESULTS: No statistically significant differences were observed among the three groups with respect to the rate of hemodynamic change. In all groups, systolic BP, diastolic BP, MAP, and SVR tended to increase after decreasing for the first 4 minutes; in contrast, HR and CO decreased until 8 minutes, after which they tended to reach a plateau. CONCLUSIONS: For patients under general anesthesia receiving dopamine at 10 µg/kg/min, there were no clinical differences in the effect of dopamine administered through three different peripheral veins.
Subject(s)
Humans , Anesthesia, General , Arterial Pressure , Blood Pressure , Cardiac Output , Dopamine , Heart Rate , Hemodynamics , Intubation , Jugular Veins , Saphenous Vein , Vascular Resistance , VeinsABSTRACT
As the treatment of chronic non-cancer pain gradually increases, clinicians have more opportunities to encounter opioid prescription. However, guidelines for prescribing opioids for chronic non-cancer pain have never been published in Korea. The present guidelines were prepared by reviewing various research data. In cases in which the data were insufficient, recommendations were presented following discussion among experts affiliated with the Opioids Research Group in the Korean Pain Society. The present guidelines may need to be continuously revised and amended as more clinical evidence is acquired.
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Analgesics, Opioid , Korea , PrescriptionsABSTRACT
BACKGROUND: We compared the analgesic efficacy and side effects of ketorolac and nefopam that were co-administered with fentanyl via intravenous patient-controlled analgesia. METHODS: One hundred and sixty patients scheduled for laparoscopic cholecystectomy were randomly assigned to ketorolac (Group K) or nefopam (Group N) groups. The anesthetic regimen was standardized for all patients. The analgesic solution contained fentanyl 600 µg and ketorolac 180 mg in Group K, and fentanyl 600 µg and nefopam 120 mg in Group N. The total volume of analgesic solution was 120 ml. Postoperative analgesic consumption, recovery of pulmonary function, and pain intensities at rest and during the forced expiration were evaluated at postoperative 2, 6, 24, and 48 h. The postoperative side effects of analgesics were recorded. RESULTS: Cumulative postoperative analgesic consumptions at postoperative 48 h were comparable (Group K: 93.4 ± 24.0 ml vs. Group N: 92.9 ± 26.1 ml, P = 0.906) between the groups. Pain scores at rest and during deep breathing were similar at the time of each examination. The recovery of pulmonary function showed no significant differences between the groups. Overall, postoperative nausea and vomiting incidence was higher in Group N compared with Group K (59% vs. 34%, P = 0.015). The other side effects were comparable between both groups. CONCLUSIONS: Analgesic efficacies of ketorolac and nefopam that were co-administered with fentanyl for postoperative pain management as adjuvant analgesics were similar. However, postoperative nausea and vomiting incidence was higher in the nefopam-fentanyl combination compared with the ketorolac-fentanyl combination.
Subject(s)
Humans , Analgesia, Patient-Controlled , Analgesics , Cholecystectomy, Laparoscopic , Fentanyl , Incidence , Ketorolac , Nefopam , Pain, Postoperative , Postoperative Nausea and Vomiting , Prospective Studies , RespirationABSTRACT
BACKGROUND: Although the use of postoperative opioids is a well-known risk factor for postoperative nausea and vomiting (PONV), few studies have been performed on the effects of intraoperative opioids on PONV. We examined the effects of a single bolus administration of fentanyl during anesthesia induction and the intraoperative infusion of remifentanil on PONV. METHODS: Two hundred and fifty women, aged 20 to 65 years and scheduled for thyroidectomy, were allocated to a control group (Group C), a single bolus administration of fentanyl 2 microg/kg during anesthesia induction (Group F), or 2 ng/ ml of effect-site concentration-controlled intraoperative infusion of remifentanil (Group R) groups. Anesthesia was maintained with sevoflurane and 50% N2O. The incidence and severity of PONV and use of rescue antiemetics were recorded at 2, 6, and 24 h postoperatively. RESULTS: Group F showed higher incidences of nausea (60/82, 73% vs. 38/77, 49%; P = 0.008), vomiting (40/82, 49% vs. 23/77 30%; P = 0.041) and the use of rescue antiemetics (47/82, 57% vs. 29/77, 38%; P = 0.044) compared with Group C at postoperative 24 h. However, there were no significant differences in the incidence of PONV between Groups C and R. The overall incidences of PONV for postoperative 24 h were 49%, 73%, and 59% in Groups C, F, and R, respectively (P = 0.008). CONCLUSIONS: A single bolus administration of fentanyl 2 microg/kg during anesthesia induction increases the incidence of PONV, but intraoperative remifentanil infusion with 2 ng/ml effect-site concentration did not affect the incidence of PONV.
Subject(s)
Female , Humans , Analgesics, Opioid , Anesthesia , Antiemetics , Fentanyl , Incidence , Intraoperative Period , Nausea , Postoperative Nausea and Vomiting , Risk Factors , Thyroidectomy , VomitingABSTRACT
The original article contained an error in Figure and Figure legend.
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BACKGROUND: This study was performed to compare the incidence of emergence agitation (EA) between inhalation and intravenous anesthesia induction in children after sevoflurane anesthesia. METHODS: In this prospective and double-blind study, 100 children aged 3 to 7 years were enrolled. Subjects were randomly assigned to the sevoflurane (Group S) or thiopental (Group T) anesthesia induction groups. Anesthesia was induced using 8% sevoflurane and 4-6 mg/kg thiopental in Groups S and T, respectively. Anesthesia was maintained with nitrous oxide and sevoflurane. The children were evaluated at 5 and 20 min after arrival in the postanesthesia care unit (PACU) with a four-point agitation scale and the Pediatric Anesthesia Emergence Delirium scale. The incidence of EA and administration of the rescue agent were recorded. RESULTS: The incidence of EA was significantly lower in Group T compared to Group S at 5 min after PACU arrival (3/49 patients, 6% vs. 12/47 patients, 26%, P = 0.019). However, there was no difference between the two groups at 20 min after PACU arrival (23/49 vs. 19/47 patients in Group T vs. Group S, P = 0.425). The overall incidence of EA was 60% (28/47 patients) in Group S and 41% (20/49 patients) in Group T (P = 0.102). The number of children who received propofol as a rescue agent was significantly lower in Group T (Group S: 14/47 vs. Group T: 5/49, P = 0.031). CONCLUSIONS: Intravenous anesthesia induction with thiopental reduced the incidence of EA in the early PACU period compared to inhalation induction with sevoflurane in 3- to 7-year-old children undergoing sevoflurane anesthesia.
Subject(s)
Child , Humans , Anesthesia , Anesthesia, Intravenous , Delirium , Dihydroergotamine , Double-Blind Method , Incidence , Inhalation , Nitrous Oxide , Pediatrics , Propofol , Prospective Studies , ThiopentalABSTRACT
BACKGROUND: The proper cuff pressure is important to prevent complications related to the endotracheal tube (ETT). We evaluated the change in ETT cuff pressure by changing the position from supine to prone without head movement. METHODS: Fifty-five patients were enrolled and scheduled for lumbar spine surgery. Neutral angle, which was the angle on the mandibular angle between the neck midline and mandibular inferior border, was measured. The initial neutral pressure of the ETT cuff was measured, and the cuff pressure was subsequently adjusted to 26 cmH2O. Flexed or extended angles and cuff pressure were measured in both supine and prone positions, when the patient's head was flexed or extended. Initial neutral pressure in prone was compared with adjusted neutral pressure (26 cmH2O) in supine. Flexed and extended pressure were compared with adjusted neutral pressure in supine or prone, respectively. RESULTS: There were no differences between supine and prone position for neutral, flexed, and extended angles. The initial neutral pressure increased after changing position from supine to prone (26.0 vs. 31.5 +/- 5.9 cmH2O, P < 0.001). Flexed and extended pressure in supine were increased to 38.7 +/- 6.7 (P < 0.001) and 26.7 +/- 4.7 cmH2O (not statistically significant) than the adjusted neutral pressure. Flexed and extended pressure in prone were increased to 40.5 +/- 8.8 (P < 0.001) and 29.9 +/- 8.7 cmH2O (P = 0.002) than the adjusted neutral pressure. CONCLUSIONS: The position change from supine to prone without head movement can cause a change in ETT cuff pressure.
Subject(s)
Humans , Head Movements , Head , Neck , Prone Position , SpineABSTRACT
BACKGROUND: Caudal epidural injections have been commonly performed in patients with low back pain and radiculopathy. Although caudal injection has generally been accepted as a safe procedure, serious complications such as inadvertent intravascular injection and dural puncture can occur. The present prospective study was designed to investigate the influence of the depth of the inserted needle on the success rate of caudal epidural blocks. METHODS: A total of 49 adults scheduled to receive caudal epidural injections were randomly divided into 2 groups: Group 1 to receive the caudal injection through a conventional method, i.e., caudal injection after advancement of the needle 1 cm into the sacral canal (n = 25), and Group 2 to receive the injection through a new method, i.e., injection right after penetrating the sacrococcygeal ligament (n = 24). Ultrasound was used to identify the sacral hiatus and to achieve accurate needle placement according to the allocated groups. Contrast dyed fluoroscopy was obtained to evaluate the epidural spread of injected materials and to monitor the possible complications. RESULTS: The success rates of the caudal injections were 68.0% in Group 1 and 95.8% in Group 2 (P = 0.023). The incidences of intravascular injections were 24.0% in Group 1 and 0% in Group 2 (P = 0.022). No intrathecal injection was found in either of the two groups. CONCLUSIONS: The new caudal epidural injection technique tested in this study is a reliable alternative, with a higher success rate and lower risk of accidental intravascular injection than the conventional technique.
Subject(s)
Adult , Humans , Anesthesia, Caudal , Fluoroscopy , Incidence , Injections, Epidural , Injections, Spinal , Ligaments , Low Back Pain , Needles , Prospective Studies , Punctures , Radiculopathy , UltrasonographyABSTRACT
No abstract available.
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BACKGROUND: Recently, multi-planar reconstruction of the three-dimensional (3D) spiral chest CT scan has demonstrated superiority in the evaluation of the tracheobronchial tree. The goal of this study was to measure the lengths of the right and left main bronchi and their anteroposterior (AP) and transverse (TR) diameters using the 3D and two-dimensional (2D) images in the same adult respectively, and to evaluate the degree of correlation between them. METHODS: We measured the lengths of the right and left main bronchi from the carina to the first of their branches and the AP and TR diameters at the mid-portion of the right main bronchus and 2 cm below the carina in the left main bronchus. We determined the size of the left-sided double-lumen tube (DLT) based on the measured AP diameter of the left main bronchus from the 3D and 2D images, respectively. RESULTS: There was moderate correlation between the lengths of both main bronchi obtained from the 3D images and the 2D images, and between the AP diameter of the left main bronchus obtained from the 3D images and the 2D images. Same sized DLTs were estimated in 69% of the men and 34% of the women. CONCLUSIONS: The lengths of the right and left main bronchi and their AP and TR diameters obtained from 3D images were not strongly correlated with those from 2D images. Therefore, a further study is needed to verify the superiority of 3D images in selecting the appropriate size of left-sided DLT.