ABSTRACT
BACKGROUND AND PURPOSE: Quantification of changes in optic nerve sheath diameter (ONSD) using ocular sonography (OS) constitutes an elegant technique for estimating intracranial and intraspinal pressure. Aortic aneurysm repair (AAR) is associated with a reasonable risk of increased spinal fluid pressure, which is largely dependent on the extent of aneurysm repair (supra- vs. infrarenal). The aim of this study was to compare ONSD measurements in patients with suprarenal AAR (sAAR) or infrarenal AAR (iAAR). METHODS: Thirty patients who underwent elective endovascular repair of infrarenal aortic aneurysms (Group iAAR) were included in the study; the characteristics in these cases were prospectively analyzed and compared with those in a previously investigated group of 28 patients treated for suprarenal aortic aneurysms (Group sAAR). Six measurements of ONSDs were performed in each patient at five consecutive time points. Statistical analysis was performed using the Wilcoxon test. A P value < .05 was considered statistically significant. RESULTS: A highly significant difference between pre- and postinterventional values could be detected in both patient groups (P < .01). In Group sAAR, there was a mean .3-mm increase of the ONSD, whereas in Group iAAR, a mean .2-mm decrease could be detected. Both groups roughly reached baseline values by the end of their inpatient stay. CONCLUSIONS: ONSD changes seem to be a reliable marker to estimate spinal perfusion. Since OS provides a suitable bedside tool for rapid reevaluation, it may guide physicians in the identification and treatment of patients at high risk for spinal cord ischemia.
Subject(s)
Angioplasty/adverse effects , Aortic Aneurysm, Abdominal/surgery , Endovascular Procedures/adverse effects , Optic Nerve/diagnostic imaging , Spinal Cord Ischemia/physiopathology , Spinal Cord/blood supply , Aged , Aged, 80 and over , Aortic Aneurysm, Abdominal/physiopathology , Body Weights and Measures , Catheterization , Cerebrospinal Fluid/physiology , Female , Humans , Male , Middle Aged , Pressure , Prospective Studies , Spinal Cord Ischemia/etiology , UltrasonographyABSTRACT
BACKGROUND & PURPOSE: Thoracic endovascular aortic repair (TEVAR) is associated with a reasonable risk of spinal ischemia. As cerebrospinal fluid pressure (CSFP) is correlated with the rate of paraplegia, a non-invasive method to estimate CSFP could help to estimate the patient's individual risk and guide the therapeutic approach. The quantification of the optic nerve sheath diameter (ONSD) using ocular sonography (OS) could be a suitable technique and was examined in the present study. METHODS: 28 patients with TEVAR were included. Five consecutive measurements of the ONSD were performed in each patient. The first before the intervention ("baseline"), the next immediately postinterventional at the intensive care unit (post1), measurements 3, 4 (post2, post3) on day 1 and 2 after the intervention and number 5 (post4) before discharge. Statistical analysis was done using the Wilcoxon-test. A p-value < 0.05 was considered statistically significant. RESULTS: A significant increase between baseline and post1-measurements (right eye: p = 0.006; left eye: p = 0.02) could be detected. A significant decrease was detected between post1 and post3 (right eye: p = 0.02; left eye: p < 0.01). A group of 5 patients had an additional increase of ONSD from post1 to post2, one of these patients developed a permanent paraplegia. Patients with spinal catheters had significantly lower ONSDs at nearly all time points. CONCLUSION: The present study is the first to prospectively examine and prove the possibility to monitor CSFP changes in patients with TEVAR associated transient spinal edema using OS. Systematic factors as artificial ventilation and body positioning did not have a significant effect.
