Magnetic resonance imaging and computed tomography as tools for the investigation of sperm whale (Physeter macrocephalus) teeth and eye

TY - JOUR

T1 - Magnetic resonance imaging and computed tomography as tools for the investigation of sperm whale (Physeter macrocephalus) teeth and eye

AU - Alstrup, Aage Kristian Olsen

AU - Munk, Ole Lajord

AU - Jensen, Trine Hammer

AU - Jensen, Lasse Fast

AU - Hedayat, Abdi

AU - Hansen, Brian

PY - 2017/6/12

Y1 - 2017/6/12

N2 - Background: Scanning techniques such as magnetic resonance imaging (MRI) and computed tomography (CT) are useful tools in veterinary and human medicine. Here we demonstrate the usefulness of these techniques in the study of the anatomy of wild marine mammals as part of a necropsy. MRI and CT scans of sperm whale teeth (n = 4) were performed. The methods were compared and further compared to current standard methods for evaluation of tooth layering. For MRI a zero echo time sequence was used, as previously done for imaging of intact human teeth. For CT two different clinical scanners were used. Results: The three scanners did not provide sufficient information to allow age estimation, but both MRI and CT provided anatomical information about the tooth cortex and medulla without the need for sectioning the teeth. MRI scanning was also employed for visualizing the vascularization of an intact eye from one of the stranded sperm whale. Conclusions: Clearly, MRI was useful for investigation of the retinal vasculation, but optimum results would require well-preserved tissue. It was not possible to estimate age based on CT scans of tooth growth lines. Further research is needed to clarify the usability of MRI and CT as tools for marine mammal research when samples need to remain intact or when a spatial (three dimensional) arrangement of features needs to be determined.

AB - Background: Scanning techniques such as magnetic resonance imaging (MRI) and computed tomography (CT) are useful tools in veterinary and human medicine. Here we demonstrate the usefulness of these techniques in the study of the anatomy of wild marine mammals as part of a necropsy. MRI and CT scans of sperm whale teeth (n = 4) were performed. The methods were compared and further compared to current standard methods for evaluation of tooth layering. For MRI a zero echo time sequence was used, as previously done for imaging of intact human teeth. For CT two different clinical scanners were used. Results: The three scanners did not provide sufficient information to allow age estimation, but both MRI and CT provided anatomical information about the tooth cortex and medulla without the need for sectioning the teeth. MRI scanning was also employed for visualizing the vascularization of an intact eye from one of the stranded sperm whale. Conclusions: Clearly, MRI was useful for investigation of the retinal vasculation, but optimum results would require well-preserved tissue. It was not possible to estimate age based on CT scans of tooth growth lines. Further research is needed to clarify the usability of MRI and CT as tools for marine mammal research when samples need to remain intact or when a spatial (three dimensional) arrangement of features needs to be determined.

KW - Computer tomography

KW - Eyes

KW - Imaging techniques

KW - Magnetic resonance

KW - Sperm whales

KW - Teeth

UR - http://www.scopus.com/inward/record.url?scp=85020459278&partnerID=8YFLogxK

U2 - 10.1186/s13028-017-0307-y

DO - 10.1186/s13028-017-0307-y

M3 - Journal article

C2 - 28606113

AN - SCOPUS:85020459278

SN - 0044-605X

VL - 59

JO - Acta Veterinaria Scandinavica

JF - Acta Veterinaria Scandinavica

M1 - 38

ER -