Neuroradiology Skull Objectives Know the radiographic features of the following diseases and underlying causes and generate appropriate differential lists Kari L Anderson DVM College of Veterinary Medicine University of Minnesota Neuroradiology Knowledge of anatomy extremely important Exact positioning is critical General anesthesia for small animal Heavy sedation for large animal Multiple oblique and tangential views Complementary studies CT MRI Intraoral views Craniomandibular Osteopathy CMO Radiographic findings Irregular or smooth opaque new bone Generally bilateral Ankylosis of TMJ may occur Ceases with maturity and can remodel to normal CMO Otitis Rhinitis Sinusitis Recognize radiographic features of skull trauma Recognize radiographic features of skull neoplasia Craniomandibular Osteopathy CMO Young dogs 3 8 months of age Terrier breeds Labs Dobes GSD Boxers Osteoproliferative disorder that is selflimiting and slows at 7 8 months of age Painful can have difficulty opening jaws Secondary TMJ fusion can occur Craniomandibular Osteopathy CMO Radiographic findings Irregular or smooth opaque new bone Generally bilateral Ankylosis of TMJ may occur Ceases with maturity 1 Otitis Externa and Media Craniomandibular Osteopathy CMO Radiographs very helpful in evaluation even better with CT or MRI Otitis interna is clinical diagnosis Can evaluate inner ear with MRI Rule out trauma tumor nasopharyngeal polyps Otitis Media and Externa dog Otitis Externa and Media Radiographic findings No abnormalities Narrowing obliteration mineralization of external ear canals otitis externa Otitis media Left bulla normal Soft tissue fluid opacity in tympanic bulla Bony changes of bulla Mineral and lack of air in canal Chronic otitis externa dog Sclerotic bulla DV view Right bulla diseased Otitis Media and Temporohyoid Osteopathy horse Otitis Media and Externa cat Sclerotic petrous bone bulla R L oblique Increased opacity and thickened bone bullae Temporohyoid articulation Soft tissue in external ear canal Normal Stylohyoid bones DV L R oblique DV view Lateral view 2 Nondestructive Rhinitis Etiologies Infection bacterial viral parasitic Foreign bodies Nasopharyngeal polyps Allergies Coagulopathy Nondestructive Rhinitis Radiographic findings Increased soft tissue fluid opacity of nasal passages and frontal sinuses May see radiopaque foreign body Should not see lysis unless very chronic infection or foreign body Open mouth VD view Nondestructive Rhinitis Nondestructive Rhinitis Increased soft tissue opacity Skyline view of front sinuses Close up lateral view Nasopharyngeal Polyp Nasal foreign body Lateral view Destructive Rhinitis Etiologies Nasal tumor Fungal infection Chronic infection or foreign bodies Most common clinical sign is epistaxis CT or MRI offers better evaluation Destructive Rhinitis Radiographic findings Early may mimic nondestructive Irregular opacities in nasal passages and frontal sinuses Bony lysis of ethmoid turbinates or nasal septum May see extranasal extension lysis Increased soft tissue opacity Nasal adenocarcinoma 3 Destructive Rhinitis Radiographic findings Early may mimic nondestructive Irregular opacities in nasal passages and frontal sinuses Bony lysis of ethmoid turbinates or nasal septum May see extranasal extension Destructive Rhinitis Increased soft tissue opacity and lysis Soft tissue extension with gas Lateral view Open mouth VD view lysis Destructive Rhinitis Coccidiomycosis Sinusitis Dental Disease horse Common indication for skull radiography Sinusitis commonly caused by empyema from tooth root abscess Other causes of sinusitis trauma FB cyst fungal granuloma ethmoid hematoma neoplasia Radiographic findings Fluid opacity in sinus Fluid lines Dental disease Sclerosis of affected tooth Widening of periodontal space Lysis of alveolar bone Nasal adenocarcinoma Sinusitis Dental Disease Sinusitis Dental Disease Alveolar sclerosis Widening of periodontal space Fluid in maxillary sinus Lateral view Tooth root infection 3rd and 4th maxillary premolars 4 Sinusitis Dental Disease Dental Disease Alveolar sclerosis Blunted root with apical lucency Tooth root abscess right 4th mandibular premolar Tooth root abscess 1st maxillary molar Sinusitis Sinusitis Nasal mass Ethmoid Hematoma horse Middle aged to older 6 years old Slowly progressive non neoplastic mass Arises from ethmoid endoturbinate or floor of the sinuses Mild persistent spontaneous intermittent and unilateral epistaxis or blood stained mucopurulent discharge DDx neoplasia cyst granuloma polyp Ethmoid Hematoma Radiographic findings Obtain lateral DV oblique round smoothly marginated mass Often single May deform septum turbinates 5 Skull Trauma Lateral and DV give global view Complex anatomy Trauma Need additional views based upon suspected trauma CT may be needed to better assess bone MRI may be needed if suspect neurologic trauma Soft tissue swelling gas foreign objects Abnormal radiolucent lines in and displacements of osseous structures Intra oral DV Lateral DV Ballistic Trauma in dog Trauma Fractures horses Right zygomatic and left maxillary fractures Fractures Lateral view Common Underlying bony injury often more pronounced than facial deformity Epistaxis Chronic mucopurulent discharge Radiographic findings Obtain at least one tangential view Depressed area in bone Abnormal radiolucent lines Fluid in sinuses Fractures Tangential view with marker on depression 6 Fractures Skull Neoplasia Both soft tissue and osseous origin Oral masses Skull Neoplasia Osteosarcoma in a dog Need to assess both soft tissues and bones Benign epulid Malignant fibrosarcoma squamous cell carcinoma malignant melanoma Primary bone tumors of mandible and maxilla Skull Neoplasia Squamous Cell Carcinoma in a cat 7