Comparison of radiography and magnetic resonance imaging for evaluating the extent of nasal neoplasia in dogs

Abstract

Minor but significant extension beyond the nasal cavity, which is important for treatment planning and prognosis, requires magnetic resonance imaging for demonstration, although radiography shows major changes reliably.

Comparison of computed tomography and magnetic resonance imaging for the evaluation of canine intranasal neoplasia

“…All transverse imaging studies showed typical characteristics of nasal neoplasia, as described previously (Thrall and others 1989, Moore and others 1991, Burk 1992, Voges and Ackerman 1995, Saunders and others 2003, Lefebvre and others 2005, Sako and others 2005, Petite and Dennis 2006, Tromblee and others 2006, Avner and others 2008, Miles and others 2008).…”

“…MRI facilitated accurate tumour localisation and permitted identification of the extent of the soft tissue mass both within and external to the nasal cavity. Tumours had increased signal intensity on T2‐weighted images and enhancement on T1‐weighted postcontrast images (Voges and Ackerman 1995, Petite and Dennis 2006, Avner and others 2008, Miles and others 2008). High signal intensity in peritumoral brain tissue on T2‐weighted images is consistent with peritumoral oedema (Moore and others 1991).…”

Advances in small animal oncology

“…Many institutions now have CT and/or MRI facilities and even general practices have access to mobile MRI units or local hospital facilities in some cases. These imaging techniques assist greatly in determining the local extent of a tumour and in deciding whether surgical excision is feasible and will achieve reasonable margins without compromising vital structures, as illustrated in the case of the intermandibular tumour reported in this issue (Murphy and others 2006, Petite and Dennis 2006). They are also invaluable in planning fields for radiotherapy in cases which are not amenable to surgery (Petite and Dennis 2006).…”

Prognostic significance of specific magnetic resonance imaging features in canine nasal tumours treated by radiotherapy

“…Clinical signs include nasal discharge, epistaxis, facial deformity, and in some patients neurological abnormalities (predominantly seizures) due to extension into the cranium (MacEwen and others 1977, Norris 1979, Legendre and others 1983, Patnaik 1989, Smith and others 1989). The advent of computed tomography (CT) and magnetic resonance imaging (MRI) has provided more accurate assessment of tumour extent than radiography, which is of particular importance for the planning of radiotherapy (Thrall and others 1989, Park and others 1992, Petite and Dennis 2006, Avner and others 2008). With palliative hypofractionated megavoltage treatment of canine nasal tumours, a median survival time (MST) of seven months has been reported (Mellanby and others 2002).…”