BACKGROUND: Elevated intracranial pressure (ICP), a disadvantage of laparoscopic or robotic surgery, is caused by the steep angle of the Trendelenburg position and the CO₂ pneumoperitoneum. Recently, sonographically measured optic nerve sheath diameter (ONSD) was suggested as a simple and non-invasive method for detecting increased ICP. This study aimed to explore the changes in ONSD in relation to different anesthetic agents used in gynecologic surgery.METHODS: Fifty patients were randomly allocated to two groups, sevoflurane (group SEV, n = 25) and propofol-based total intravenous anesthesia (TIVA) group (group TIVA, n = 25). The ONSD was measured at five time points (T0–T4): T0 was measured 5 min after induction of anesthesia in the supine position; T1, T2, and T3 were measured at 5, 15, and 30 min after CO₂ pneumoperitoneum induction in the Trendelenburg position; and T4 was measured at 5 min after discontinuation of CO₂ pneumoperitoneum in the supine position. Respiratory and hemodynamic variables were also recorded.RESULTS: The intra-group changes in mean ONSD in the Trendelenburg position were significantly increased in both groups. However, inter-group changes in mean ONSD were not significantly different at T0, T1, T2, T3, and T4. Heart rates in group TIVA were significantly lower than those in group SEV at points T1–T4.CONCLUSIONS: There was no significant difference in the ONSD between the two groups until 30 min into the gynecologic surgery with CO₂ pneumoperitoneum in the Trendelenburg position. This study suggests that there is no difference in the ONSD between the two anesthetic methods.
Anesthesia ; Anesthesia, Intravenous ; Anesthetics ; Female ; Gynecologic Surgical Procedures ; Head-Down Tilt ; Heart Rate ; Hemodynamics ; Humans ; Intracranial Hypertension ; Methods ; Optic Nerve ; Pneumoperitoneum ; Propofol ; Supine Position ; Ultrasonography

OBJECTIVE: While the optic nerve sheath diameter (ONSD) is measured by computed tomography and ultrasonography as an indicator of an elevation in the intracranial pressure (ICP), it is unclear which ONSD measurement is useful for predicting an increased ICP. This study examined the comparability between the ONSD measured by computed tomography and ultrasonography. METHODS: A prospective study of 150 patients in the emergency center was performed. The ONSD was measured 3 mm behind the globe of all patients by computed tomography and ultrasonography. The receiver operator characteristic (ROC) curve was analyzed to determine the diagnostic utility of detecting ICP through ONSD. RESULTS: A total of 150 patients were enrolled. Thirty-three patients (22.0%) were found to have an increased ICP. The ONSD in patients with increased ICP was significantly higher than that of normal ICP patients measured by computed tomography and ultrasonography. Moreover, computed tomography and ultrasonography revealed an area under the ROC curve value of 0.886 and 0.933, respectively. The ONSD measurement by computed tomography and ultrasonography produced similar results (P=0.256). CONCLUSION: The ONSD measured by computed tomography and ultrasonography is a valuable indicator of an ICP elevation. Therefore, either of the two diagnostic methods for monitoring the ICP can be used in patients with a critical care and resource-limited setup.
Critical Care ; Emergencies ; Humans ; Intracranial Pressure ; Optic Nerve ; Prospective Studies ; ROC Curve ; Ultrasonography

In ultrasound/computed tomography (CT) fusion images, ultrasound allows visualization of the target in real time. CT provides a navigation for ultrasound scanning and improves the overview in areas of limited visualization with ultrasound. This study was performed to investigate the feasibility of ultrasound/CT fusion based on an electromagnetic tracking technique using external fiducial markers for canine ocular and periocular regions. In 7 Beagle dogs, contrast-enhanced CT images of the head were obtained with placing external fiducial markers over the frontal region and both sides of the forepaws of the dog. Ultrasonography was performed under a magnetic field by installing a position sensor in the linear probe, without changing the dog's position. The positions of the external fiducial markers were adjusted and matched, based on the CT images. The execution time of co-registration and the distance between the regions of interest and the co-registration points, the frontal bone, cornea, retina, and optic nerve, were estimated. Approximately 60% of external fiducial markers were properly recognized in all dogs. After adjustment, all external fiducial markers were precisely matched. The co-registration execution time was less than 1 min. The distances between the regions of interest and co-registration points were less than 3 mm in all dogs. The electromagnetic tracking technique using external fiducial markers was a simple and applicable method for fusion imaging of a canine head using real-time ultrasonography and CT. This technique can be useful for interventional procedures of retrobulbar and periorbital lesions.
Animals ; Cornea ; Dogs ; Fiducial Markers ; Frontal Bone ; Head ; Magnetic Fields ; Magnets ; Methods ; Optic Nerve ; Retina ; Tomography, X-Ray Computed ; Ultrasonography

OBJECTIVE: To evaluate the prognostic value of ultrasonographic measurement of optic nerve sheath diameter (ONSD) and ONSD/eyeball transverse diameter (ETD) ratio in stroke patients during hospitalization. METHODS: Adult patients with stroke (ischemic stroke or hemorrhagic stroke) admitted to department of critical care medicine of Shanghai General Hospital, Shanghai Jiao Tong University School of Medicine from November 2017 to November 2018 were enrolled. On the day of admission, ONSD and ETD (retina-retina at 3 mm behind the globe along) were detected by ultrasound, the ONSD/ETD ratio was calculated, and the baseline data and outcomes were recorded. Patients were divided into survival group and death group according to their survival status. Locally weighted scatterplot smoothing (LOWESS) and the receiver operating characteristic (ROC) curve were used to calculate the thresholds of ONSD and ONSD/ETD. The correlation between ONSD, ONSD/ETD and prognosis were assessed. RESULTS: Thirty-eight of 83 patients (45.8%) survived and were discharged from the hospital, while 45 patients died (54.2%). There were significant differences in Glasgow coma score (GCS), shifting of the middle structure, ONSD and ONSD/ETD between the death group and the survival group [GCS: 4.7±2.8 vs. 11.0±3.2, shifting of the middle structure (mm): 5.8±5.9 vs. 1.3±2.6, ONSD (mm): 5.5±0.4 vs. 4.4±0.5, ONSD/ETD: 0.25±0.02 vs. 0.20±0.02, all P < 0.05]. LOWESS and ROC curve analysis suggested thresholds of ONSD and ONSD/ETD for predicting adverse prognosis of stroke patients were 5.0 mm and 0.25, respectively. By adjusting the influence of confounding factors on prognosis, a prediction model based on ONSD was established, and the ROC curve was drawn. The area under the curve (AUC) was 0.978, the optimal predictive point of the model was 0.870, the sensitivity was 89%, and the specificity was 100%. The ONSD/ETD prediction model was also obtained, and the AUC was 0.988, the optimal prediction threshold of the model was 0.768, and the sensitivity for predicting adverse clinical prognosis was 94%, and the specificity was 97%. The stability of ONSD/ETD was better than that of ONSD. ONSD coefficient of variation was 0.14, and ONSD/ETD coefficient of variation was 0.13. CONCLUSIONS ONSD and ONSD/ETD were significantly correlated with the prognosis of critical patients with stroke. The mortality increased significantly in patients with an ONSD greater than 5.0 mm and ONSD/ETD greater than 0.25. ONSD and ONSD/ETD may be promising tools for early assessment of clinical outcomes in these patients.
Adult ; China ; Hospitalization ; Humans ; Intracranial Pressure ; Optic Nerve ; Prognosis ; ROC Curve ; Stroke ; Ultrasonography

PURPOSE: An increase in optic nerve sheath diameter (ONSD) has been associated with elevated intracranial pressure due to brain lesions, such as hemorrhage, infarction, and tumor. The aim of this study was to evaluate whether the difference of both ONSDs can predict surgical treatment in patients with traumatic brain hemorrhage. METHODS: A prospective analysis of the data acquired between September 2016 and November 2016 was performed. We included 155 patients with traumatic brain hemorrhage undergoing computed tomography in the emergency room. We performed an ultrasonography to measure ONSDs for all included patients. The primary outcome of this study was operation indication in patients with traumatic brain hemorrhage. RESULTS: The average age was 63.4±17.0 years (male 60.3±17.3, female 69.8±14.4). There were 61 (39.35%) patients with an indication for operation and 94 (60.65%) patients with an indication for no operation. Indications for operation showed a strong association with the difference of both ONSDs in patients with subdural hemorrhage (p<0.001), no association between them in patients with epidural and intracerebral hemorrhage. In patients with subdural hemorrhage, the area under the curve was 0.988 (0.653-0.998), and the cut-off value for the difference of ONSDs with respect to determining the indications for operation was 0.295 mm f maximizing the sum of the sensitivity (96.9%) and specificity (90.7%) using the receiver operating curve. CONCLUSION: A difference of both ONSDs above 0.295 mm was useful in predicting the indications for operation in patients with traumatic subdural hemorrhage, but not in patients with epidural and intracerebral hemorrhage.
Brain ; Brain Hemorrhage, Traumatic* ; Cerebral Hemorrhage ; Emergency Service, Hospital ; Female ; Hematoma, Subdural ; Hemorrhage ; Humans ; Infarction ; Intracranial Hypertension ; Optic Nerve* ; Prospective Studies ; Sensitivity and Specificity ; Ultrasonography*

BACKGROUND: Increase in intracranial pressure (ICP) is one of the physiologic changes during laparoscopic surgery, which is known to be associated with positional changes. Changes of ICP can be measured directly by invasive method, but ultrasonographic measurement of optic nerve sheath diameter (ONSD) is known to be a rapidly applicable technique for evaluating ICP. The aim of this study is to investigate the change of ONSD according to the positional change during laparoscopic surgery. METHODS: Female patients scheduled to undergo laparoscopic surgery were enrolled. Fifty-seven patients were assigned according to the position during surgery (Group T: gynecological surgery, Trendelenburg position, n = 27 vs. Group RT: laparoscopic cholecystectomy, Reverse trendelenburg position, n = 30). After induction of anesthesia, ONSD, PaCO2, end-tidal carbon dioxide (ETCO2), and mean arterial pressure (MAP) were measured. Parameters were measured at 6 time points during surgery. RESULTS: There were no significant differences in the demographic data of patients, procedure time, and anesthesia. After pneumoperitoneum and positional change, ONSD, ETCO2, and MAP increased in both groups until 15 min and returned to the baseline. However, no significant differences in changes of ONSD, PaCO2, ETCO2, and MAP were observed between two groups. CONCLUSIONS: ONSD during laparoscopic surgery with pneumoperitoneum increased slightly until 15 minutes, but there were no significant differences according to the position. Increases in ICP during laparoscopic surgery with short period of pneumoperitoneum would be small in disregard of position in patients without intracranial pathology.
Anesthesia ; Arterial Pressure ; Carbon Dioxide ; Cholecystectomy, Laparoscopic ; Female ; Gynecologic Surgical Procedures ; Head-Down Tilt ; Humans ; Intracranial Pressure ; Laparoscopy* ; Optic Nerve* ; Pathology ; Pneumoperitoneum ; Ultrasonography

BACKGROUND: Rapid evaluation and management of intracranial pressure (ICP) can help to early detection of increased ICP and improve postoperative outcomes in neurocritically-ill patients. Sonographic measurement of optic nerve sheath diameter (ONSD) is a non-invasive method of evaluating increased intracranial pressure at the bedside. In the present study, we hypothesized that sonographic ONSD, as a surrogate of ICP change, can be dynamically changed in response to carbon dioxide change using short-term hyperventilation. METHODS: Fourteen patients were enrolled. During general anesthesia, end-tidal carbon dioxide concentration (ETCO2) was decreased from 40 mmHg to 30 mmHg within 10 minutes. ONSD, which was monitored continuously in the single sonographic plane, was repeatedly measured at 1 and 5 minutes with ETCO2 40 mmHg (time-point 1 and 2) and measured again at 1 and 5 minutes with ETCO2 30 mmHg (time-point 3 and 4). RESULTS: The mean +/- standard deviation of ONSD sequentially measured at four time-points were 5.0 +/- 0.5, 5.0 +/- 0.4, 3.8 +/- 0.6, and 4.0 +/- 0.4 mm, respectively. ONSD was significantly decreased at time-point 3 and 4, compared with 1 and 2 (P < 0.001). CONCLUSIONS: The ONSD was rapidly changed in response to ETCO2. This finding may support that ONSD may be beneficial to close ICP monitoring in response to CO2 change.
Anesthesia, General* ; Carbon Dioxide ; Humans ; Hyperventilation* ; Intracranial Pressure ; Optic Nerve* ; Ultrasonography

BACKGROUND: Rapid evaluation and management of intracranial pressure (ICP) can help to early detection of increased ICP and improve postoperative outcomes in neurocritically-ill patients. Sonographic measurement of optic nerve sheath diameter (ONSD) is a non-invasive method of evaluating increased intracranial pressure at the bedside. In the present study, we hypothesized that sonographic ONSD, as a surrogate of ICP change, can be dynamically changed in response to carbon dioxide change using short-term hyperventilation. METHODS: Fourteen patients were enrolled. During general anesthesia, end-tidal carbon dioxide concentration (ETCO2) was decreased from 40 mmHg to 30 mmHg within 10 minutes. ONSD, which was monitored continuously in the single sonographic plane, was repeatedly measured at 1 and 5 minutes with ETCO2 40 mmHg (time-point 1 and 2) and measured again at 1 and 5 minutes with ETCO2 30 mmHg (time-point 3 and 4). RESULTS: The mean +/- standard deviation of ONSD sequentially measured at four time-points were 5.0 +/- 0.5, 5.0 +/- 0.4, 3.8 +/- 0.6, and 4.0 +/- 0.4 mm, respectively. ONSD was significantly decreased at time-point 3 and 4, compared with 1 and 2 (P < 0.001). CONCLUSIONS: The ONSD was rapidly changed in response to ETCO2. This finding may support that ONSD may be beneficial to close ICP monitoring in response to CO2 change.
Anesthesia, General* ; Carbon Dioxide ; Humans ; Hyperventilation* ; Intracranial Pressure ; Optic Nerve* ; Ultrasonography

BACKGROUND: Early prediction of neurologic outcome is important to patients treated with therapeutic hypothermia after hypoxic brain injury. Hypoxic brain injury patients may have poor neurologic prognosis due to increased intracranial pressure. Increased intracranial pressure can be detected by optic nerve sheath diameter (ONSD) measurement in computed tomography (CT) or ultrasound. In this study, we evaluate the relation between neurologic prognosis and optic nerve sheath diameter measured in brain CT of hypoxic brain injury patients. METHODS: We analyzed the patient clinical data by retrospective chart review. We measured the ONSD in initial brain CT. We also measured and calculated the gray white matter ratio (GWR) in CT scan. We split the patients into two groups based on neurologic outcome, and clinical data, ONSD, and GWR were compared in the two groups. RESULTS: Twenty-four patients were included in this study (age: 52.6 +/- 18.3, 18 males). The mean ONSD of the poor neurologic outcome group was larger than that of the good neurologic outcome group (6.07 mm vs. 5.39 mm, p = 0.003). The GWR of the good neurologic outcome group was larger than that of the poor outcome group (1.09 vs. 1.28, p = 0.000). ONSD was a good predictor of neurologic outcome (area under curve: 0.848), and an ONSD cut off > or = 5.575 mm had a sensitivity of 86.7% and a specificity of 77.8%. CONCLUSIONS: ONSD measured on the initial brain CT scan can predict the neurologic prognosis in cardiac arrest and hanging patients treated with therapeutic hypothermia.
Brain Injuries ; Brain* ; Heart Arrest* ; Humans ; Hypothermia ; Intracranial Pressure ; Optic Nerve* ; Prognosis* ; Retrospective Studies ; Sensitivity and Specificity ; Tomography, X-Ray Computed ; Ultrasonography

PURPOSE: To evaluate orbital blood flow velocities and optic nerve diameter with Doppler and gray-scale sonography in patients with acute unilateral optic neuritis (ON). METHODS: Orbital Doppler and gray-scale sonography was performed in 46 eyes of 23 patients aged 19- to 47-years with acute unilateral ON. ON was diagnosed by an ophthalmologist on the basis of clinical presentation, presence of decreased visual acuity and assessment of visual evoked potentials. The peak systolic velocity (PSV) and end-diastolic velocity (EDV), as well as the resistance index (RI) and pulsatile index (PI) of the ophthalmic artery (OA), central retinal artery (CRA), posterior ciliary arteries (PCAs) and optic nerve diameter were measured in both eyes. We compared results from affected and unaffected eyes using the paired t-test. The area under the receiver operating characteristic (ROC) curves was used to assess the diagnosis of ON based on measured blood flow parameters of the OA, CRA and PCAs and optic nerve diameter. RESULTS: The mean (standard deviation) optic nerve diameter in eyes with ON was 4.1 (0.8) mm, which was significantly larger than the 3.0 (0.4) mm diameter measured in unaffected control eyes (p < 0.001). There were no differences in average PSV, EDV, RI, or PI of the OA and CRA between affected and unaffected eyes (p > 0.05). The mean RI in the PCAs was slightly lower in the eyes with ON than in the contralateral eyes (0.60 vs. 0.64, p < 0.05). The area under the ROC curves indicated that optic nerve diameter was the best parameter for the diagnosis of ON. CONCLUSIONS: Optic nerve diameter was related to ON, but orbital blood flow parameters were not.
Adult ; Humans ; Middle Aged ; Ophthalmic Artery/*physiology/*ultrasonography ; Optic Nerve/*blood supply/*ultrasonography ; Optic Neuritis/*physiopathology/*ultrasonography ; Orbit/blood supply/ultrasonography ; Pulsatile Flow/physiology ; Regional Blood Flow/physiology ; Ultrasonography, Doppler, Color ; Vascular Resistance/physiology ; Young Adult