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A Pilot Study: The Effect of COVID-19 on Sonographic Optic Nerve Sheath Diameter Measured for Critical Patient Management

Year 2023, , 202 - 208, 10.10.2023
https://doi.org/10.52827/hititmedj.1344000

Abstract

Objective: The aim of this study is to evaluate the effects of the Coronavirus disease 2019 on sonographic optic nerve sheath diameter measurement and thus avoid possible misleading results in clinical practice.
Material and Method: Each volunteer was first evaluated using carotid system color Doppler ultrasonography. Patients with a history of PCR-confirmed Coronavirus disease 2019 infection were classified as group 1 and patients without a history of Coronavirus disease 2019 infection were classified as group 2, and sonographic optic nerve sheath diameter values of both groups were analyzed.
Results: Of the 123 patients included in the study, 70 (56.9%) were female and 58 (43.1%) were male. 83 (67.5%) of the patients included in the study were in group 1 and 40 (32.5%) were in group 2. The mean sonographic optic nerve sheath diameter values for the groups were 3.53 mm and 3.46 mm, respectively. The sonographic optic nerve sheath diameter differences between the two eyes for the groups were determined to be 0.203±0.139 mm and 0.282±0.2 mm.
Conclusion: Due to the variable effects of Severe Acute Respiratory Syndrome Coronavirus-2, the use of sonographic optic nerve sheath diameter measurement in current standards for critical patient management may lead to false-positive or false-negative results.

Thanks

We thank Dr. Erdal KOMUT for his editing of the manuscript.

References

  • Komut E, Kozacı N, Sönmez BM, et al. Bedside sonographic measurement of optic nerve sheath diameter as a predictor of intracranial pressure in ED. The American journal of emergency medicine 2016;34:963-967.
  • Hirzallah MI, Lochner P, Hafeez MU, et al. Quality assessment of optic nerve sheath diameter ultrasonography: Scoping literature review and Delphi protocol. Journal of Neuroimaging 2022;32:808-824.
  • Hansen H, Helmke K. The subarachnoid space surrounding the optic nerves. An ultrasound study of the optic nerve sheath. Surgical and radiologic anatomy: SRA 1996;18:323-328.
  • Maissan IM, Dirven PJ, Haitsma IK, et al. Ultrasonographic measured optic nerve sheath diameter as an accurate and quick monitor for changes in intracranial pressure. Journal of neurosurgery 2015;123:743-747.
  • Geeraerts T, Launey Y, Martin L, et al. Ultrasonography of the optic nerve sheath may be useful for detecting raised intracranial pressure after severe brain injury. Intensive care medicine 2007;33:1704-1711.
  • Robba C, Santori G, Czosnyka M, et al. Optic nerve sheath diameter measured sonographically as non-invasive estimator of intracranial pressure: a systematic review and meta-analysis. Intensive care medicine 2018;44:1284-1294.
  • Dubourg J, Javouhey E, Geeraerts T, Messerer M, Kassai B. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: a systematic review and meta-analysis. Intensive care medicine 2011;37:1059-1068.
  • Yılmaz F, Sonmez BM, Kavalci C, Arslan ED, Caliskan G, Beydilli I. Efficacy of bedside optic nerve sheath diameter measurement in differentiating provoked seizure from unprovoked seizure in the emergency department. Annals of Saudi Medicine 2023;43:42-49.
  • Bekerman I, Sigal T, Kimiagar I, Almer ZE, Vaiman M. Diagnostic value of the optic nerve sheath diameter in pseudotumor cerebri. Journal of Clinical Neuroscience 2016;30:106-109.
  • Kozaci N, Avci M, Caliskan G, Yuksel S. Variability of optic nerve sheath diameter in acute ischemic stroke. Hong Kong Journal of Emergency Medicine 2020;27:223-228.
  • Yagar A, Kozaci N, Avci M, Yildiz S, Karaman, Y. Determination of optic nerve sheath diameter variability with age in pediatric groups and comparison of increased intracranial pressure and optic nerve sheath diameter in pediatric patients with head trauma. Ann Med Res 2018;25:460.
  • Komut E, Murat M, Büyükşireci M, Komut S, Kozaci N. Relationship between internal carotid artery stenosis grade and optic nerve sheath diameter measured by transorbital ultrasonography. Journal of Clinical Ultrasound 2021;49:724-730.
  • Burgos-Blasco B, Güemes-Villahoz N, Vidal-Villegas B, et al. Optic nerve and macular optical coherence tomography in recovered COVID-19 patients. European Journal of Ophthalmology 2022;32:628-636.
  • Abrishami M, Daneshvar R, Emamverdian Z, Tohidinezhad F, Eslami S. Optic nerve head parameters and peripapillary retinal nerve fiber layer thickness in patients with coronavirus disease 2019. Ocular Immunology and Inflammation 2022;30:1035-1038.
  • Zhou Z, Kang H, Li S, Zhao X. Understanding the neurotropic characteristics of SARS-CoV-2: from neurological manifestations of COVID-19 to potential neurotropic mechanisms. Journal of neurology 2020;267:2179-2184.
  • Jossy A, Jacob N, Sarkar S, Gokhale T, Kaliaperumal S, Deb AK. COVID-19-associated optic neuritis–A case series and review of literature. Indian Journal of Ophthalmology 2022;70:310.
  • Pansell J, Rudberg PC, Bell M, Friman O, Cooray C. Optic nerve sheath diameter is associated with outcome in severe Covid-19. Scientific Reports 2022;12:17255.
  • Burgos-Blasco B, Güemes-Villahoz N, Donate-Lopez J, Vidal-Villegas B, García-Feijóo J. Optic nerve analysis in COVID-19 patients. Journal of Medical Virology 2021;93:190.
  • Demir TA, Yılmaz F, Sönmez BM, Karadaş MA, Okudan RN, Keskin O. Association of optic nerve sheath diameter measurement with hyponatremia in emergency department. The American Journal of Emergency Medicine 2019;37:1876-1879.
  • Avci M, Kozaci N, Komut E, Komut S, Caliskan G, Tulubas G. The measurement of elderly volunteers’ optic nerve sheath diameters by ocular ultrasonography. Medicina.2019;55:413.
  • Akça E, Yılmaz F, Baltacıoğlu B, Tiftikçi İ, Arslan ED, Kavalcı C, et al. Bedside Ultrasonographic Assessment of the Optic Nerve Sheath Diameter to Assess Intracranial Pressure in Patients Given Ketamine in Emergency Department. Albanian Journal of Trauma and Emergency Surgery 2023;7:1273-1278.
  • Liu M-Y, Zheng B, Zhang Y, Li J-P. Role and mechanism of angiotensin-converting enzyme 2 in acute lung injury in coronavirus disease 2019. Chronic Diseases and Translational Medicine 2020;6:98-105.
  • Choudhary R, Kapoor MS, Singh A, Bodakhe SH. Therapeutic targets of renin-angiotensin system in ocular disorders. Journal of current ophthalmology 2017;29:7-16.
  • Tang N, Bai H, Chen X, Gong J, Li D, Sun Z. Anticoagulant treatment is associated with decreased mortality in severe coronavirus disease 2019 patients with coagulopathy. Journal of thrombosis and haemostasis 2020;18:1094-1099.
  • Schmitt FCF, Manolov V, Morgenstern J, et al. Acute fibrinolysis shutdown occurs early in septic shock and is associated with increased morbidity and mortality: results of an observational pilot study. Annals of intensive care 2019;9:1-15.
  • Chen N, Zhou M, Dong X, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. The lancet 2020;395:507-513.
  • Zhang Y, Cao W, Xiao M, et al. Clinical and coagulation characteristics in 7 patients with critical COVID-2019 pneumonia and acro-ischemia. Zhonghua xue ye xue za zhi 2020:302-307.
  • Nunes NDSM, Nascimento JSFD, Nascimento JKFD, et al. Brain and Covid-19: an integrative review. E-CRONICON NEUROLOGY 2020;12.
  • Catharino A, Neves M, Nunes N, Nascimento, JS, Nascimento JK. COVID-19 related optic neuritis: Case report. J Clin Neurol Neurosci 2020;1.
  • Prasad S, Galetta SL. Anatomy and physiology of the afferent visual system. Handbook of clinical neurology 2011;102:3-19.
  • Holló G, Zhou Q. Evaluation of retinal nerve fiber layer thickness and ganglion cell complex progression rates in healthy, ocular hypertensive, and glaucoma eyes with the Avanti RTVue-XR optical coherence tomography based on 5-year follow-up. Journal of Glaucoma 2016;25:e905-e909.
  • Cabrera DeBuc D, Gaca-Wysocka M, Grzybowski A, Kanclerz P. Identification of retinal biomarkers in Alzheimer’s disease using optical coherence tomography: recent insights, challenges, and opportunities. Journal of clinical medicine 2019;8:996.
  • Çakır A, Düzgün E, Demir S, Çakır Y., Ünal MH. Spectral-domain optical coherence tomography findings in carotid artery disease. Turkish Journal of Ophthalmology 2017;47:326.
  • Sayin N, Kara N, Uzun F, Akturk IF. A quantitative evaluation of the posterior segment of the eye using spectral-domain optical coherence tomography in carotid artery stenosis: a pilot study. Ophthalmic Surgery, Lasers and Imaging Retina 2015;46:180-185.
  • Utsugi N, Takahashi K, Kishi S. Choroidal vascular occlusion in internal carotid artery obstruction. Retina 2004;24:915-919.
  • Dag Seker E, Erbahceci Timur IE. COVID-19: more than a respiratory virus, an optical coherence tomography study. International Ophthalmology 2021;41:3815-3824.
  • Örnek K, Temel E, Aşıkgarip N, Kocamış Ö. Localized retinal nerve fiber layer defect in patients with COVID-19. Arquivos Brasileiros de Oftalmologia 2021;83:562-563.
  • Chan P, Mok K. Transorbital sonographic evaluation of optic nerve sheath diameter in normal Hong Kong Chinese adults. Hong Kong Journal of Emergency Medicine 2008;15:197-204.
  • Asghar A, Hashmi M, Hussain A. Optic nerve sheath diameter evaluated by transorbital sonography in healthy volunteers from Pakistan. Anesthesia, Pain & Intensive Care 2019:282-286.
  • Bäuerle J, Lochner P, Kaps M, Nedelmann M. Intra-and interobsever reliability of sonographic assessment of the optic nerve sheath diameter in healthy adults. Journal of Neuroimaging 2012;22:42-45.
  • Goeres P, Zeiler FA, Unger B, Karakitsos D, Gillman LM. Ultrasound assessment of optic nerve sheath diameter in healthy volunteers. Journal of critical care 2016;31:168-171.
  • Ballantyne S, O’neill G, Hamilton R, Hollman AS. Observer variation in the sonographic measurement of optic nerve sheath diameter in normal adults. European journal of ultrasound 2002;15:145-149.
  • Aydin N, Çapraz M. Optic Nerve and Retinal Layer Measurements with Optical Coherence Tomography in PCR Positive and Negative COVID-19 Patients. Journal of Contemporary Medicine 2022;12:1-.
  • Kim DH, Jun J-S, Kim R. Ultrasonographic measurement of the optic nerve sheath diameter and its association with eyeball transverse diameter in 585 healthy volunteers. Scientific reports 2017;7:15906.
  • Maude RR, Amir Hossain M, Hassan MU, et al. Transorbital sonographic evaluation of normal optic nerve sheath diameter in healthy volunteers in Bangladesh. PloS one 2013;8:e81013.
  • Mao L, Jin H, Wang M, et al. Neurologic manifestations of hospitalized patients with coronavirus disease 2019 in Wuhan, China. JAMA neurology 2020;77:683-690.
  • Biondino D, Costigliola R, Mottola F, Graziano M, Yılmaz F. Comment on: Optic nerve sheath diameter measurement by ultrasound and age group. Annals of Saudi Medicine 2023;43:196-197.

Bir Pilot Çalışma: Kritik Hasta Yönetimi İçin Ölçülen Sonografik Optik Sinir Kılıfı Kalınlığına COVID-19'un Etkisi

Year 2023, , 202 - 208, 10.10.2023
https://doi.org/10.52827/hititmedj.1344000

Abstract

Amaç: Bu çalışmanın amacı, Coronavirüs hastalığı 2019’un merkezi sinir sistemi üzerindeki etkileri ile ilişkili olarak; sonografik optik sinir kılıf çapı ölçümünün güvenilirliğini değerlendirmek ve böylece klinik pratikte olası yanıltıcı sonuçları önlemektir.
Gereç ve Yöntem: Her gönüllü öncelikle karotis sistemi renkli Doppler ultrasonografi kullanılarak değerlendirildi. PCR ile doğrulanmış Coronavirüs hastalığı 2019 enfeksiyonu öyküsü olan hastalar grup 1, Coronavirüs hastalığı 2019 enfeksiyonu öyküsü olmayan hastalar ise grup 2 olarak sınıflandırılarak her iki grubun sonografik optik sinir kılıfı çapı değerleri analiz edildi.
Bulgular: Çalışmaya dahil edilen 123 hastanın 70’i (%56,9) kadın, 58’i (%43,1) erkekti. Çalışmaya dahil edilen hastaların 83’ü (%67,5) grup 1’de, 40’ı (%32,5) grup 2’de yer aldı. Grupların ortalama sonografik optik sinir kılıfı çapı değerleri sırasıyla 3,53 mm ve 3,46 mm idi. Gruplar için iki göz arasındaki sonografik optik sinir kılıf çapı farkları 0,203±0,139 mm ve 0,282±0,2 mm olarak belirlendi.
Sonuç: Severe Acute Respiratory Syndrome Coronavirus-2’nin değişken etkileri nedeniyle, kritik hasta yönetimi için mevcut standartlarda sonografik optik sinir kılıf çapı ölçümünün kullanılması yanlış pozitif veya yanlış negatif sonuçlara yol açabilir.

References

  • Komut E, Kozacı N, Sönmez BM, et al. Bedside sonographic measurement of optic nerve sheath diameter as a predictor of intracranial pressure in ED. The American journal of emergency medicine 2016;34:963-967.
  • Hirzallah MI, Lochner P, Hafeez MU, et al. Quality assessment of optic nerve sheath diameter ultrasonography: Scoping literature review and Delphi protocol. Journal of Neuroimaging 2022;32:808-824.
  • Hansen H, Helmke K. The subarachnoid space surrounding the optic nerves. An ultrasound study of the optic nerve sheath. Surgical and radiologic anatomy: SRA 1996;18:323-328.
  • Maissan IM, Dirven PJ, Haitsma IK, et al. Ultrasonographic measured optic nerve sheath diameter as an accurate and quick monitor for changes in intracranial pressure. Journal of neurosurgery 2015;123:743-747.
  • Geeraerts T, Launey Y, Martin L, et al. Ultrasonography of the optic nerve sheath may be useful for detecting raised intracranial pressure after severe brain injury. Intensive care medicine 2007;33:1704-1711.
  • Robba C, Santori G, Czosnyka M, et al. Optic nerve sheath diameter measured sonographically as non-invasive estimator of intracranial pressure: a systematic review and meta-analysis. Intensive care medicine 2018;44:1284-1294.
  • Dubourg J, Javouhey E, Geeraerts T, Messerer M, Kassai B. Ultrasonography of optic nerve sheath diameter for detection of raised intracranial pressure: a systematic review and meta-analysis. Intensive care medicine 2011;37:1059-1068.
  • Yılmaz F, Sonmez BM, Kavalci C, Arslan ED, Caliskan G, Beydilli I. Efficacy of bedside optic nerve sheath diameter measurement in differentiating provoked seizure from unprovoked seizure in the emergency department. Annals of Saudi Medicine 2023;43:42-49.
  • Bekerman I, Sigal T, Kimiagar I, Almer ZE, Vaiman M. Diagnostic value of the optic nerve sheath diameter in pseudotumor cerebri. Journal of Clinical Neuroscience 2016;30:106-109.
  • Kozaci N, Avci M, Caliskan G, Yuksel S. Variability of optic nerve sheath diameter in acute ischemic stroke. Hong Kong Journal of Emergency Medicine 2020;27:223-228.
  • Yagar A, Kozaci N, Avci M, Yildiz S, Karaman, Y. Determination of optic nerve sheath diameter variability with age in pediatric groups and comparison of increased intracranial pressure and optic nerve sheath diameter in pediatric patients with head trauma. Ann Med Res 2018;25:460.
  • Komut E, Murat M, Büyükşireci M, Komut S, Kozaci N. Relationship between internal carotid artery stenosis grade and optic nerve sheath diameter measured by transorbital ultrasonography. Journal of Clinical Ultrasound 2021;49:724-730.
  • Burgos-Blasco B, Güemes-Villahoz N, Vidal-Villegas B, et al. Optic nerve and macular optical coherence tomography in recovered COVID-19 patients. European Journal of Ophthalmology 2022;32:628-636.
  • Abrishami M, Daneshvar R, Emamverdian Z, Tohidinezhad F, Eslami S. Optic nerve head parameters and peripapillary retinal nerve fiber layer thickness in patients with coronavirus disease 2019. Ocular Immunology and Inflammation 2022;30:1035-1038.
  • Zhou Z, Kang H, Li S, Zhao X. Understanding the neurotropic characteristics of SARS-CoV-2: from neurological manifestations of COVID-19 to potential neurotropic mechanisms. Journal of neurology 2020;267:2179-2184.
  • Jossy A, Jacob N, Sarkar S, Gokhale T, Kaliaperumal S, Deb AK. COVID-19-associated optic neuritis–A case series and review of literature. Indian Journal of Ophthalmology 2022;70:310.
  • Pansell J, Rudberg PC, Bell M, Friman O, Cooray C. Optic nerve sheath diameter is associated with outcome in severe Covid-19. Scientific Reports 2022;12:17255.
  • Burgos-Blasco B, Güemes-Villahoz N, Donate-Lopez J, Vidal-Villegas B, García-Feijóo J. Optic nerve analysis in COVID-19 patients. Journal of Medical Virology 2021;93:190.
  • Demir TA, Yılmaz F, Sönmez BM, Karadaş MA, Okudan RN, Keskin O. Association of optic nerve sheath diameter measurement with hyponatremia in emergency department. The American Journal of Emergency Medicine 2019;37:1876-1879.
  • Avci M, Kozaci N, Komut E, Komut S, Caliskan G, Tulubas G. The measurement of elderly volunteers’ optic nerve sheath diameters by ocular ultrasonography. Medicina.2019;55:413.
  • Akça E, Yılmaz F, Baltacıoğlu B, Tiftikçi İ, Arslan ED, Kavalcı C, et al. Bedside Ultrasonographic Assessment of the Optic Nerve Sheath Diameter to Assess Intracranial Pressure in Patients Given Ketamine in Emergency Department. Albanian Journal of Trauma and Emergency Surgery 2023;7:1273-1278.
  • Liu M-Y, Zheng B, Zhang Y, Li J-P. Role and mechanism of angiotensin-converting enzyme 2 in acute lung injury in coronavirus disease 2019. Chronic Diseases and Translational Medicine 2020;6:98-105.
  • Choudhary R, Kapoor MS, Singh A, Bodakhe SH. Therapeutic targets of renin-angiotensin system in ocular disorders. Journal of current ophthalmology 2017;29:7-16.
  • Tang N, Bai H, Chen X, Gong J, Li D, Sun Z. Anticoagulant treatment is associated with decreased mortality in severe coronavirus disease 2019 patients with coagulopathy. Journal of thrombosis and haemostasis 2020;18:1094-1099.
  • Schmitt FCF, Manolov V, Morgenstern J, et al. Acute fibrinolysis shutdown occurs early in septic shock and is associated with increased morbidity and mortality: results of an observational pilot study. Annals of intensive care 2019;9:1-15.
  • Chen N, Zhou M, Dong X, et al. Epidemiological and clinical characteristics of 99 cases of 2019 novel coronavirus pneumonia in Wuhan, China: a descriptive study. The lancet 2020;395:507-513.
  • Zhang Y, Cao W, Xiao M, et al. Clinical and coagulation characteristics in 7 patients with critical COVID-2019 pneumonia and acro-ischemia. Zhonghua xue ye xue za zhi 2020:302-307.
  • Nunes NDSM, Nascimento JSFD, Nascimento JKFD, et al. Brain and Covid-19: an integrative review. E-CRONICON NEUROLOGY 2020;12.
  • Catharino A, Neves M, Nunes N, Nascimento, JS, Nascimento JK. COVID-19 related optic neuritis: Case report. J Clin Neurol Neurosci 2020;1.
  • Prasad S, Galetta SL. Anatomy and physiology of the afferent visual system. Handbook of clinical neurology 2011;102:3-19.
  • Holló G, Zhou Q. Evaluation of retinal nerve fiber layer thickness and ganglion cell complex progression rates in healthy, ocular hypertensive, and glaucoma eyes with the Avanti RTVue-XR optical coherence tomography based on 5-year follow-up. Journal of Glaucoma 2016;25:e905-e909.
  • Cabrera DeBuc D, Gaca-Wysocka M, Grzybowski A, Kanclerz P. Identification of retinal biomarkers in Alzheimer’s disease using optical coherence tomography: recent insights, challenges, and opportunities. Journal of clinical medicine 2019;8:996.
  • Çakır A, Düzgün E, Demir S, Çakır Y., Ünal MH. Spectral-domain optical coherence tomography findings in carotid artery disease. Turkish Journal of Ophthalmology 2017;47:326.
  • Sayin N, Kara N, Uzun F, Akturk IF. A quantitative evaluation of the posterior segment of the eye using spectral-domain optical coherence tomography in carotid artery stenosis: a pilot study. Ophthalmic Surgery, Lasers and Imaging Retina 2015;46:180-185.
  • Utsugi N, Takahashi K, Kishi S. Choroidal vascular occlusion in internal carotid artery obstruction. Retina 2004;24:915-919.
  • Dag Seker E, Erbahceci Timur IE. COVID-19: more than a respiratory virus, an optical coherence tomography study. International Ophthalmology 2021;41:3815-3824.
  • Örnek K, Temel E, Aşıkgarip N, Kocamış Ö. Localized retinal nerve fiber layer defect in patients with COVID-19. Arquivos Brasileiros de Oftalmologia 2021;83:562-563.
  • Chan P, Mok K. Transorbital sonographic evaluation of optic nerve sheath diameter in normal Hong Kong Chinese adults. Hong Kong Journal of Emergency Medicine 2008;15:197-204.
  • Asghar A, Hashmi M, Hussain A. Optic nerve sheath diameter evaluated by transorbital sonography in healthy volunteers from Pakistan. Anesthesia, Pain & Intensive Care 2019:282-286.
  • Bäuerle J, Lochner P, Kaps M, Nedelmann M. Intra-and interobsever reliability of sonographic assessment of the optic nerve sheath diameter in healthy adults. Journal of Neuroimaging 2012;22:42-45.
  • Goeres P, Zeiler FA, Unger B, Karakitsos D, Gillman LM. Ultrasound assessment of optic nerve sheath diameter in healthy volunteers. Journal of critical care 2016;31:168-171.
  • Ballantyne S, O’neill G, Hamilton R, Hollman AS. Observer variation in the sonographic measurement of optic nerve sheath diameter in normal adults. European journal of ultrasound 2002;15:145-149.
  • Aydin N, Çapraz M. Optic Nerve and Retinal Layer Measurements with Optical Coherence Tomography in PCR Positive and Negative COVID-19 Patients. Journal of Contemporary Medicine 2022;12:1-.
  • Kim DH, Jun J-S, Kim R. Ultrasonographic measurement of the optic nerve sheath diameter and its association with eyeball transverse diameter in 585 healthy volunteers. Scientific reports 2017;7:15906.
  • Maude RR, Amir Hossain M, Hassan MU, et al. Transorbital sonographic evaluation of normal optic nerve sheath diameter in healthy volunteers in Bangladesh. PloS one 2013;8:e81013.
  • Mao L, Jin H, Wang M, et al. Neurologic manifestations of hospitalized patients with coronavirus disease 2019 in Wuhan, China. JAMA neurology 2020;77:683-690.
  • Biondino D, Costigliola R, Mottola F, Graziano M, Yılmaz F. Comment on: Optic nerve sheath diameter measurement by ultrasound and age group. Annals of Saudi Medicine 2023;43:196-197.
There are 47 citations in total.

Details

Primary Language English
Subjects Emergency Medicine, Radiology and Organ Imaging
Journal Section Research Articles
Authors

Seval Komut 0000-0002-9558-4832

Nurdan Fidan 0000-0002-2995-6220

Publication Date October 10, 2023
Submission Date August 15, 2023
Acceptance Date September 23, 2023
Published in Issue Year 2023

Cite

AMA Komut S, Fidan N. A Pilot Study: The Effect of COVID-19 on Sonographic Optic Nerve Sheath Diameter Measured for Critical Patient Management. Hitit Medical Journal. October 2023;5(3):202-208. doi:10.52827/hititmedj.1344000