title: Association between axial length and horizontal and vertical globe diameters.
abstract: OBJECTIVE
  To assess relationships between axial length and the horizontal and vertical globe diameters.
  
  
  METHODS
  The study consisted of enucleated human eyes. The horizontal, vertical, and sagittal diameters were measured.
  
  
  RESULTS
  The study included 135 globes removed because of malignant uveal melanoma (111 globes) or end-stage painful glaucoma (n = 24 eyes). Mean axial, horizontal, and vertical diameters were 24.6 ± 2.6 mm (range: 20-35 mm), 23.7 ± 1.4 mm (range: 21-29 mm) and 23.7 ± 1.4 mm (range: 20-29 mm) respectively. The horizontal diameter and vertical diameter did not differ significantly (P = 0.92), while both were significantly (P < 0.001) shorter than the axial diameter. The horizontal diameter was significantly and linearly correlated with the vertical globe diameter (P < 0.001; regression line: vertical globe diameter = 0.84 × horizontal globe diameter + 3.69). The axial diameter was significantly (P < 0.001) associated with the horizontal diameter and vertical diameters in a bipartite manner. In eyes with an axial length ≤24 mm, horizontal and vertical diameters increased by 0.44 and 0.51 mm, respectively, for each mm increase in axial diameter, while in eyes with an axial length >24 mm, the horizontal and vertical globe diameter increased by a lower amount of 0.19 and 0.21 mm, respectively, for each mm increase in axial diameter.
  
  
  CONCLUSIONS
  Myopic enlargement of the globe beyond an axial length of 24 mm takes place predominantly in the sagittal axis, leading to a change in the globe form from a sphere to an elongated form. It fits with the notion that myopic elongation may occur by an elongation of the eye walls in regions close to the globe's equator.
authors.affiliation: Department of Ophthalmology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany. Jost.Jonas@medma.uni-heidelberg.de.
authors.forename: Jost B
authors.initials: JB
authors.lastname: Jonas
authors.affiliation: Department of Ophthalmology and Visual Science, Tokyo Medical and Dental University, Tokyo, Japan.
authors.forename: Kyoko
authors.initials: K
authors.lastname: Ohno-Matsui
authors.affiliation: Department of Ophthalmology, Friedrich-Alexander University Erlangen-Nürnberg, Erlangen, Germany.
authors.forename: Leonard
authors.initials: L
authors.lastname: Holbach
authors.affiliation: Department of Ophthalmology, Medical Faculty Mannheim, Heidelberg University, Mannheim, Germany.
authors.forename: Songhomitra
authors.initials: S
authors.lastname: Panda-Jonas
mesh_terms: D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D058452:Axial Length, Eye / Q000473:pathology*; D005123:Eye / Q000473:pathology*; D015353:Eye Enucleation; D005260:Female; D005901:Glaucoma / Q000175:diagnosis / Q000601:surgery; D006801:Humans; D008297:Male; D008545:Melanoma / Q000175:diagnosis / Q000601:surgery; D008875:Middle Aged; D009216:Myopia / Q000473:pathology*; D014604:Uveal Neoplasms / Q000175:diagnosis / Q000601:surgery; D055815:Young Adult; D000098943:Uveal Melanoma
keywords: Axial length; Eye diameter; Eye size; Globe diameter; High myopia; Myopia; Ocular elongation; Sclera