Background: Measuring optic nerve sheath diameter (ONSD), a relatively re-cent technique, allows an indirect and non-invasive diagnosis of intracranial hypertension. The ONSD ratio to eyeball transverse diameter (ETD) increases this reliability of the technique. The objective of this study was to determine the normal ONSD and its ratio with ETD in black African adults in Benin. Methods: A descriptive cross-sectional study was conducted between May 2019 and August 2019. Ultrasound ONSD and ONSD/ETD ratio were meas-ured in 210 healthy adults received in the medical imaging department of the Borgou and Alibori University Hospital Center in Benin. The ONSD corre-sponded to the average of 12 measurements (03 horizontal and 03 vertical for each eye) taken 3 mm behind the papilla. The transverse ETD corresponded to the average of 03 measurements. Results: The mean ONSD was 4.20 ± 0.28 mm (95% CI = [4.17; 4.24] mm and 95th percentile = 4.70 mm). The mean ETD was 24.25 ± 1.10 mm. The ONSD/ETD ratio was 0.17 ± 0.01 (95% CI = [0.17; 0.17] and 95th percentile = 0.19). There was no difference between ver-tical and horizontal ONSD and between right and left ONSD. The ONSD and the ONSD/ETD ratio were not correlated with any of the socio-demographic and anthropometric characteristics studied (sex, age, ethnicity, weight, height, body mass index, head circumference and waist circumference). The ONSD was associated with ETD (p < 0.001 and r = 0.55). Conclusion: An ONSD and an ONSD/ETD ratio respectively greater than 4.70 mm and 0.19 should sus-pect intracranial hypertension. The ONSD/ETD ratio may be a better indicator of HICT because of its small variation.
References
[1]
Stevens, R.D., Shoykhet, M. and Cadena, R. (2015) Emergency Neurological Life Support: Intracranial Hypertension and Herniation. Neurocritical Care, 23, 76-82.
https://doi.org/10.1007/s12028-015-0168-z
[2]
Raboel, P.H., Bartek, J., Andresen, M., Bellander, B.M. and Romner, B. (2012) Intracranial Pressure Monitoring: Invasive versus Non-Invasive Methods: A Review. Critical Care Research and Practice, 2012, Article ID: 950393.
https://doi.org/10.1155/2012/950393
[3]
Czosnyka, M., Pickard, J.D. and Steiner, L.A. (2017) Principles of Intracranial Pressure Monitoring and Treatment. Handbook of Clinical Neurology, 140, 67-89.
https://doi.org/10.1016/B978-0-444-63600-3.00005-2
[4]
Canac, N., Jalaleddini, K., Thorpe, S.G., Thibeault, C.M. and Hamilton, R.B. (2020) Review: Pathophysiology of Intracranial Hypertension and Noninvasive Intracranial Pressure Monitoring. Fluids Barriers CNS, 17, 1-21.
https://doi.org/10.1186/s12987-020-00201-8
[5]
Krakauskaite, S., Petkus, V., LBartusis, A., Zakelis, R., Chomskis, R., Preiksaitis, A., et al. (2016) Accuracy, Precision, Sensitivity, and Specificity of Noninvasive ICP Absolute Value Measurements. Acta Neurochirurgica (Wien), 122, 317-321.
https://doi.org/10.1007/978-3-319-22533-3_63
[6]
Evensen, K.B. and Eide, P.K. (2020) Measuring Intracranial Pressure by Invasive, Less Invasive or Non-Invasive Means: Limitations and Avenues for Improvement. Fluids Barriers CNS, 17, 1-33. https://doi.org/10.1186/s12987-020-00195-3
[7]
Hansen, H.C. and Helmke, K. (1997) Validation of the Optic Nerve Sheath Response to Changing Cerebrospinal Fluid Pressure: Ultrasound Findings during Intrathecal Infusion Tests. Journal of Neurosurgery, 87, 34-40.
https://doi.org/10.3171/jns.1997.87.1.0034
[8]
Hansen, H.C., Lagrèze, W., Krueger, O. and Helmke, K. (2011) Dependence of the Optic Nerve Sheath Diameter on Acutely Applied Subarachnoidal Pressure—An Experimental Ultrasound Study. Acta Ophthalmologica, 89, 528-532.
https://doi.org/10.1111/j.1755-3768.2011.02159.x
[9]
Liu, D., Li, Z., Zhang, X., Zhao, L., Jia, J., Sun, F., et al. (2017) Assessment of Intracranial Pressure with Ultrasonographic Retrobulbar Optic Nerve Sheath Diameter Measurement. BMC Neurology, 17, 188. https://doi.org/10.1186/s12883-017-0964-5
[10]
De Moraes, C.G. (2013) Anatomy of the Visual Pathways. Journal of Glaucoma, 22, S2-S7. https://doi.org/10.1097/IJG.0b013e3182934978
[11]
Ballantyne, S.A., O’Neill, G., Hamilton, R. and Hollman, A.S. (2002) Observer Variation in the Sonographic Measurement of Optic Nerve Sheath Diameter in Normal Adults. European Journal of Ultrasound, 15, 145-149.
https://doi.org/10.1016/S0929-8266(02)00036-8
[12]
Bäuerle, J. and Nedelmann, M. (2012) B-Mode Sonography of the Optic Nerve in Neurological Disorders with Altered Intracranial Pressure. Perspectives in Medicine, 1, 404-407. https://doi.org/10.1016/j.permed.2012.01.001
[13]
Lochner, P., Coppo, L., Cantello, R., Nardone, R., Naldi, A., Leone, M.A., et al. (2016) Intra- and Interobserver Reliability of Transorbitalsonographic Assessment of the Optic Nerve Sheath Diameter and Optic Nerve Diameter in Healthy Adults. Journal of Ultrasound, 19, 41-45. https://doi.org/10.1007/s40477-014-0144-z
[14]
Bekerman, I., Sigal, T., Kimiagar, I., Ben Ely, A. and Vaiman, M. (2016) The Quantitative Evaluation of Intracranial Pressure by Optic Nerve Sheath Diameter/Eye Diameter CT Measurement. American Journal of Emergency Medicine, 34, 2336-2342.
https://doi.org/10.1016/j.ajem.2016.08.045
[15]
Kim, D.H., Jun, J.-S. and Kim, R. (2018) Measurement of the Optic Nerve Sheath Diameter with Magnetic Resonance Imaging and Its Association with Eyeball Diameter in Healthy Adults. Journal of Clinical Neurology, 14, 345-350.
https://doi.org/10.3988/jcn.2018.14.3.345
[16]
Du, J., Deng, Y., Li, H., Qiao, S., Yu, M., Xu, Q., et al. (2020) Ratio of Optic Nerve Sheath Diameter to Eyeball Transverse Diameter by Ultrasound Can Predict Intracranial Hypertension in Traumatic Brain Injury Patients: A Prospective Study. Neurocritical Care, 32, 478-485. https://doi.org/10.1007/s12028-019-00762-z
[17]
Maude, R.R., Amir Hossain, M., Hassan, M.U., Osbourne, S., Sayeed, K.L.A., Karim, M.R., et al. (2013) Transorbitalsonographic Evaluation of Normal Optic Nerve Sheath Diameter in Healthy Volunteers in Bangladesh. PLoS ONE, 8, e81013.
https://doi.org/10.1371/journal.pone.0081013
[18]
Chan, P.Y.N. and Mok, K.L. (2008) Transorbitalsonographic Evaluation of Optic Nerve Sheath Diameter in Normal Hong Kong Chinese Adults. Hong Kong Journal of Emergency Medicine, 15, 197-204. https://doi.org/10.1177/102490790801500402
[19]
Shrestha, G.S. (2016) Transorbitalsonographic Evaluation of Normal Optic Nerve Sheath Diameter in Healthy Nepalese Adults. Journal of Neuroanesthesiology and Critical Care, 3, 115-118. https://doi.org/10.4103/2348-0548.182343
[20]
Hadijat Oluseyi, K.-Y. and Ukamaka, I. (2017) Ultrasonograhic Measurement of Optic Nerve Sheath Diameter in Normal Adults. Annals of International Medical and Dental Research, 3, 30-34. https://doi.org/10.21276/aimdr.2017.3.2.RD9
[21]
Blehar, D.J., Gaspari, R.J., Montoya, A. and Calderon, R. (2008) Correlation of Visual Axis and Coronal Axis Measurements of the Optic Nerve Sheath Diameter. Journal of Ultrasound in Medicine, 27, 407-411.
https://doi.org/10.7863/jum.2008.27.3.407
[22]
Kim, D.H., Jun, J.S. and Kim, R. (2017) Ultrasonographic Measurement of the Optic Nerve Sheath Diameter and Its Association with Eyeball Transverse Diameter in 585 Healthy Volunteers. Scientific Reports, 7, Article No. 15906.
https://doi.org/10.1038/s41598-017-16173-z
[23]
Chen, H., Ding, G.S., Zhao, Y.C., Yu, R.G. and Zhou, J.X. (2015) Ultrasound Measurement of Optic Nerve Diameter and Optic Nerve Sheath Diameter in Healthy Chinese Adults. BMC Neurology, 15, 106.
https://doi.org/10.1186/s12883-015-0361-x
[24]
Lefferts, W.K., Hughes, W.E. and Heffernan, K.S. (2015) Effect of Acute High-Intensity Resistance Exercise on Optic Nerve Sheath Diameter and Ophthalmic Artery Blood Flow Pulsatility. Journal of Human Hypertension, 29, 744-748.
https://doi.org/10.1038/jhh.2015.12
[25]
Goeres, P., Zeiler, F.A., Unger, B., Karakitsos, D. and Gillman, L.M. (2015) Ultrasound Assessment of Optic Nerve Sheath Diameter in Healthy Volunteers. Journal of Critical Care, 31, 168-171. https://doi.org/10.1016/j.jcrc.2015.10.009
[26]
Wang, L., Feng, L., Yao, Y., Deng, F., Wang, Y., Feng, J., et al. (2016) Ultrasonographic Evaluation of Optic Nerve Sheath Diameter among Healthy Chinese Adults. Ultrasound in Medicine and Biology, 42, 683-688.
https://doi.org/10.1016/j.ultrasmedbio.2015.11.020
[27]
Helmke, K. and Hansen, H.C. (1996) Fundamentals of Transorbitalsonographic Evaluation of Optic Nerve Sheath Expansion under Intracranial Hypertension. I. Experimental Study. Pediatric Radiology, 26, 701-705.
https://doi.org/10.1007/BF01383383
[28]
Anas, I. (2014) Transorbitalsonographic Measurement of Normal Optic Sheath Nerve Diameter in Nigerian Adult Population. Malaysian Journal of Medical Sciences, 21, 24-29.
[29]
Amini, R., Stolz, L.A., Patanwala, A.E. and Adhikari, S. (2015) Coronal Axis Measurement of the Optic Nerve Sheath Diameter Using a Linear Transducer. Journal of Ultrasound in Medicine, 34, 1607-1612. https://doi.org/10.7863/ultra.15.14.09039
[30]
Vaiman, M., Gottlieb, P. and Bekerman, I. (2014) Quantitative Relations between the Eyeball, the Optic Nerve, and the Optic Canal Important for Intracranial Pressure Monitoring. Head & Face Medicine, 10, Article No. 32.
https://doi.org/10.1186/1746-160X-10-32
