European Radiology

, Volume 29, Issue 3, pp 1365–1374 | Cite as

Ex vivo orbital volumetry using stereology and CT imaging: A comparison with manual planimetry

  • Georgios BontzosEmail author
  • Michael Mazonakis
  • Efrosini Papadaki
  • Thomas G. Maris
  • Styliani Blazaki
  • Eleni E. Drakonaki
  • Efstathios T. Detorakis
Head and Neck



To evaluate the applicability of stereology and planimetry in orbital volume measurements using computed tomography (CT) and to compare the results between the two measurements.


Experimental study using sheep craniums for CT imaging. Water filling measurements were performed, as the validation technique. Quantification techniques were also evaluated in five human subjects. To examine the proportion of agreement among measurements, we tested intra- and inter-observer agreement.


For stereology customization, a 1/8 systematic sampling scheme was considered as optimal; this resulted in a low coefficient of error (2.59 %) and low measurement time (1.9 mins). In sheep craniums, mean volume measured by water displacement, planimetry and stereology was 17.81 ± 0.59 cm3, 17.87 ± 0.68 cm3 and 17.54 ± 0.49 cm3, respectively. Total volumes, obtained by stereology, were highly correlated with the water-filling method (r=0.893; p = 0.001) and a paired t-test showed significant difference between methods (t=3.047; p = 0.014). Planimetry results displayed a high correlation with the water-filling method (r=0.957; p ≈ 0.001) but no statistically significant difference was found (p = 0.154). Mean difference using planimetry and stereology was 0.332 ± 0.322 cm3. In human subjects, using stereology, the estimated volume ranged between 18.57 cm3 and 19.27 cm3, and the mean orbital volume was 19.05 ± 0.50 cm3 with CE=3.75 ± 0.16 %. Mean measure time was 2.1 ± 0.1 mins.


Stereological measurements were superior to manual planimetry in terms of user effort and time spent. Stereology sampling of 1/8 was successfully applied in human subjects and yielded a strong correlation with manual planimetry.

Key Points

• Stereology can be applied to measure the orbital volume using computed tomography.

• Stereological measurements display high correlation with gold standard planimetry and combine low coefficient of error (2.59%) with low measurement time (1.9 min).

• Stereology is superior in terms of user effort and time spent.


Orbit Eye Skull Anatomy 



Coefficient of error


Computed tomography


Intraclass correlation coefficient


Magnetic resonance imaging


Standard deviation



This study has received funding by the General Secretariat for Research and Technology (GSRT) and the Hellenic Foundation for Research and Innovation (HFRI).

Compliance with ethical standards


The scientific guarantor of this publication is Efstathios Detorakis.

Conflict of interest

The authors of this manuscript declare no relationships with any companies whose products or services may be related to the subject matter of the article.

Statistics and biometry

One of the authors has significant statistical expertise.

Informed consent

Written informed consent was obtained from all subjects (patients) in this study.

Ethical approval

Institutional Review Board approval was obtained.


• Prospective

• Experimental

• Performed at one institution


  1. 1.
    Alinasab B, Beckman MO, Pansell T, Abdi S, Westermark AH, Stjärne P (2011) Relative difference in orbital volume as an indication for surgical reconstruction in isolated orbital floor fractures. Craniomaxillofac Trauma Reconstr. 4:203–212Google Scholar
  2. 2.
    Imai K, Fujimoto T, Takahashi M, Maruyama Y, Yamaguchi K (2013) Preoperative andpostoperative orbital volume in patients with Crouzon and Apert syndrome. J Craniofac Surg 24:191–194Google Scholar
  3. 3.
    Schiff BA, McMullen CP, Farinhas J et al (2015) Use of computed tomography to assess volume change after endoscopic orbital decompression for Graves' ophthalmopathy. Am J Otolaryngol 36:729–735CrossRefGoogle Scholar
  4. 4.
    Sung YS, Chung CM, Hong IP (2013) The correlation between the degree of enophthalmos and the extent of fracture in medial orbital wall fracture left untreated for over six months: a retrospective analysis of 81 cases at a single institution. Arch Plast Surg. 40:335–340CrossRefGoogle Scholar
  5. 5.
    Oh TS, Jeong WS, Chang TJ, Koh KS, Choi JW (2016) Customized orbital wall reconstruction using three-dimensionally printed rapid prototype model in patients with orbital wall fracture. J Craniofac Surg. 27:2020–2024Google Scholar
  6. 6.
    Forbes G, Gorman CA, Gehring D, Baker HL Jr (1983) Computer analysis of orbital fat and muscle volumes in Graves ophthalmopathy. AJNR Am J Neuroradiol. 4:737–740Google Scholar
  7. 7.
    Forbes G, Gehring DG, Gorman CA, Brennan MD, Jackson IT (1985) Volume measurements of normal orbital structures by computed tomographic analysis. AJR Am J Roentgenol. 145:149–154Google Scholar
  8. 8.
    McGurk M, Whitehouse RW, Taylor PM, Swinson B (1992) Orbital volume measured by a low-dose CT scanning technique. Dentomaxillofac Radiol. 21:70–72Google Scholar
  9. 9.
    Lutzemberger L, Salvetti O (1998) Volumetric analysis of CT orbital images. Med Biol Eng Comput. 36661-666Google Scholar
  10. 10.
    Deveci M, Oztürk S, Sengezer M, Pabuşcu Y (2000) Measurement of orbital volume by a 3-dimensional software program: an experimental study. J Oral Maxillofac Surg. 58:645–648Google Scholar
  11. 11.
    Warfield SK, Kaus M, Jolesz FA, Kikinis R (2000) Adaptive, template moderated, spatially varying statistical classification. Med Image Anal. 4:43–55Google Scholar
  12. 12.
    Bartling SH, Majdani O, Gupta R et al (2007) Large scan field, high spatial resolution flat-panel detector based volumetric CT of the whole human skull base and for maxillofacial imaging. Dentomaxillofac Radiol. 36:317–327CrossRefGoogle Scholar
  13. 13.
    Bijlsma WR, Mourits MP (2006) Radiologic measurement of extraocular muscle volumes in patients with Graves' orbitopathy: a review and guideline. Orbit. 25:83–91CrossRefGoogle Scholar
  14. 14.
    Cooper WC (1985) A method for volume determination of the orbit and its contents by high resolution axial tomography and quantitative digital image analysis. Trans Am Ophthalmol Soc. 83:546–609Google Scholar
  15. 15.
    Acer N, Sahin B, Ergür H, Basaloglu H, Ceri NG (2009) Stereological estimation of the orbital volume: a criterion standard study. J Craniofac Surg. 20:921–925Google Scholar
  16. 16.
    Mazonakis M, Karampekios S, Damilakis J, Voloudaki A, Gourtsoyiannis N (2004) Stereological estimation of total intracranial volume on CT images. Eur Radiol. 14:1285–1290Google Scholar
  17. 17.
    Unal B, Kara A, Aksak S, Unal D (2010) A stereological assessment method for estimating the surface area of cycloids. Eurasian J Med 42:66–73Google Scholar
  18. 18.
    Bilgic S, Sahin B, Sonmez OF et al (2005) A new approach for the estimation of intervertebral disc volume using the Cavalieri principle and computed tomography images. Clin Neurol Neurosurg 107:282–288CrossRefGoogle Scholar
  19. 19.
    Gundersen HJ, Jensen EB (1987) The efficiency of systematic sampling in stereology and its prediction. J Microsc. 147:229–263CrossRefGoogle Scholar
  20. 20.
    Roberts N, Puddephat MJ, McNulty V (2000) The benefit of stereology for quantitative radiology. Br J Radiol. 73:679–697CrossRefGoogle Scholar
  21. 21.
    Mazonakis M, Damilakis J, Varveris H (1998) Bladder and rectum volume estimations using CT and stereology. Comput Med Imaging Graph. 22:195–201CrossRefGoogle Scholar
  22. 22.
    Furuta M (2001) Measurement of orbital volume by computed tomography: especially on the growth of the orbit. Jpn J Ophthalmol. 45:600–606CrossRefGoogle Scholar
  23. 23.
    Sugamata A, Yoshizawa N (2010) Clinical analysis of orbital blowout fractures caused by a globe-to-wall contact mechanism. J Plast Surg Hand Surg. 44:278–281CrossRefGoogle Scholar
  24. 24.
    Sahin B, Emirzeoglu M, Uzun A et al (2003) Unbiased estimation of the liver volume by the Cavalieri principle using magnetic resonance images. Eur J Radiol. 47:164–170CrossRefGoogle Scholar
  25. 25.
    Mazonakis M, Pagonidis K, Damilakis J (2011) Right ventricular volumes and ejection fraction by MR imaging and stereology: comparison with standard image analysis method. Clin Anat. 24:868–873CrossRefGoogle Scholar
  26. 26.
    Mazonakis M, Stratakis J, Damilakis J (2015) Efficient stereological approaches for the volumetry of a normal or enlarged spleen from MDCT images. Eur Radiol. 25:1761–1767CrossRefGoogle Scholar
  27. 27.
    Emirzeoglu M, Sahin B, Selcuk MB, Kaplan S (2005) The effects of section thickness on the estimation of liver volume by the Cavalieri principle using computed tomography images. Eur J Radiol. 56:391–397Google Scholar

Copyright information

© European Society of Radiology 2018

Authors and Affiliations

  1. 1.Department of OphthalmologyUniversity Hospital of HeraklionCreteGreece
  2. 2.Department of Medical PhysicsUniversity of CreteHeraklionGreece
  3. 3.Department of RadiologyUniversity Hospital of HeraklionHeraklionGreece
  4. 4.Independent Imaging ServicesCreteGreece

Personalised recommendations