@article{ref1,
title="Perioperative variation in optic nerve sheath diameter - a prospective observational study of traumatic brain injury patients undergoing decompressive craniectomy",
journal="Neurology India",
year="2022",
author="Suresh, Varun and Ushakumari, P. R. and Aggarwal, Anurag and Kumar, Arun and Kutty, Raja K. and Prabhakar, Rajmohan B. and Peethambaran, Anilkumar",
volume="70",
number="4",
pages="1460-1467",
abstract="BACKGROUND: Measuring optic nerve sheath diameter (ONSD) by transbulbar ultrasonography (TBUS) can suffice non-invasive ICP measurement with considerable accuracy. <br><br>OBJECTIVE: The primary objective of this study was to evaluate the perioperative variation in ONSD by TBUS in Traumatic Brain Injury (TBI) patients undergoing emergency craniectomy. <br><br>METHODS: We prospectively compared bilateral ONSD measurements in 45 consecutive TBI cases undergoing decompressive craniectomy under general anesthesia; before and after surgery. A total of 180 ONSD images were obtained and measurements were done by the same investigator blinded to the pre/postoperative nature of the image. <br><br>RESULTS: Based on preoperative Glasgow Coma Scores, 34 cases (75.5%) had severe TBI; 10 cases (22.2%) moderate TBI; and 1 case (2.2%) mild TBI. Preoperative ONSD in the study population were as 6.625 ± 0.414mm. Average ONSD reduced significantly by 0.249 ± 0.148 mm (P < 0.001) after craniectomy. On pooled analysis of cases undergoing right versus left sided craniectomy average ONSD reduced significantly by 0.252 ± 0.173 mm (P < 0.001) and 0.259 ± 0.139 mm (P < 0.001), respectively. ONSD of right eye with left eye and vice-versa were strongly correlated both pre/postoperatively with Pearson correlation coefficients (r)=0.879 (P < 0.001) and r = 0.827 (P < 0.001), respectively. <br><br>CONCLUSIONS: In TBI cases undergoing decompressive craniectomy ONSD is bilaterally increased preoperatively. ONSD reduces significantly immediately after craniectomy; however, the diameters did not near the normal range. There hold a strong correlation between right/left ONSD measurements irrespective of the laterality of injury or side of surgery. Variable elastic properties of ONS in an injured brain can possibly explain our findings.<p /> <p>Language: en</p>",
language="en",
issn="0028-3886",
doi="10.4103/0028-3886.355178",
url="http://dx.doi.org/10.4103/0028-3886.355178"
}