A technique is proposed for applying well-established stereological methods to study fixed nasal biopsy material to obtain an unbiased estimate of blood vessel surface and volume densities. Biopsies of the nasal mucosa from the anterior 10 mm of an inferior turbinate were obtained from 18 subjects (15 males, 3 females with a mean age of 28.5 years [range: 17-54 years]), ten of whom had perennial allergic rhinitis, and eight control subjects. The mucosal tissue volumes were estimated by water displacement. Zamboni's-fixed cryostat sections (10 microns thick), stained with haematoxylin and eosin, were examined histologically. Computerised images of randomly selected tissue sections were analysed with point-counting and intercept-counting techniques to determine large blood vessel volume and surface densities, respectively. There were no significant differences between the volumes of tissue analysed from the control and rhinitic subjects (p = 0.35). The average volume density of the vessels was similar in the control group (6.17 +/- 1.41%) and the rhinitic group (7.8 +/- 5.59%; p = 0.38), but with a greater variability in the rhinitic group. Surface density estimations were 3.14 +/- 0.74 mm-1 in the control group and 3.10 +/- 1.41 mm-1 in the rhinitic group. Therefore, on average, the volume and surface densities of the cavernous blood vessels in rhinitis were unaltered and there was no evidence of vascular remodelling.