Rokka, DamodarPoudel, SharmaKayastha, PrakashSuwal, SundarPoudyal, SudilChhetry, SarojLohani, BenuShrestha, ShantalallKarn, Rakesh2026-04-012026-04-012020https://hdl.handle.net/20.500.14572/5550Damodar Rokka1, Sharma Poudel2, Prakash Kayastha2, Sundar Suwal2, Sudil Poudyal3, Saroj Chhetry4, Benu Lohani2, Shantalall Shrestha2, Rakesh Karn5 1Departement of Radiology, National Trauma Center, National Academy of Medical Sciences (NAMS), Kathmandu 2Department of Radiology, Maharajgunj Medical Campus, Tribhuvan University Teaching Hospital, Institute of Medicine, Kathmandu 3Department of Radiology, Chitwan Medical College, Chitwan 4Department of Radiology, Sahid Gangalal National Heart Center, Kathmandu 5Department of Radiology, Grande International Hospital, KathmanduABSTRACT Introduction: Normal orbital dimensions are important for diagnosing orbital pathologies. Computed tomography (CT) of the orbit is an important modality offering high accuracy for precise measurements of orbit. The study was disbursed to ascertain criteria for the normative values of the various orbital dimensions using computed tomography in patients visiting Tribhuvan University Teaching Hospital, Kathmandu. Methods: Orbital volume, ocular diameter, length of the interzygomatic line (IZL), the distance of the posterior extent of the globe from the interzygomatic line, globe position, diameters of extraocular muscles (medial, lateral, superior group, and inferior rectus) and lens density were measured in each eye of 172 patients undergoing CT examination of paranasal sinuses. The correlations with age and sex were also analyzed. Results: Mean values (mean±SD) of orbital volume, ocular diameter, IZL, globe position and lens density were 24.54±2.57 cm3, 2.44±0.22 cm, 94.3±6.2 mm, 12.3±2.4 mm and 141.43±16.62 HU respectively. Mean diameters of extraocular muscles were 3.67± 0.52 mm, 3.36± 0.50 mm, 3.74±0.42 mm and 3.87±0.38 mm for medial rectus, lateral rectus, inferior rectus and the superior group respectively. There was no significant age and gender difference in most of the measurements. There was significant positive correlation of age with lens density, orbital volume and ocular diameter (p<0.05). Conclusion: Normative data of different orbital measurements were obtained. The present result may help radiologists and ophthalmologists to accurately assess various orbital parameters, particularly in Nepalese populations. Keywords: CT, measurements, orbiten-USCTmeasurementsorbitArticle