Equine Skull 2

sihirlifil's version from 2017-12-05 21:23

Part 2

Question Answer
Radiographic signs of periapical infection (tooth root abscess)Loss of lamina dura
Lysis of periapical bone
Widening of periodontal space
Sclerosis of adjacent alveolar bone
Plump/blunted appearance of affected tooth root(s), sometimes associated framents
+/- associated granuloma formation in sinus/around tooth roots, may mineralize
+/- sinusitis
**Mandibular tooth root abscess may lead to formation of sinus with purulent discharge**
Associated with infundibular necrosis
What’s going on with these 2 rads?
Left side: Periapical infection of M1: mineralized granulation tissue in adjacent maxillary sinus
Right side: NORMAL! Need oblique projections of maxillary arcades to differentiate sides
Mandibular tooth root abscesses often present how?Discharging sinus with marked palisading periosteal reaction along the cortex of ramus
Mandibular tooth root abscess with draining tract & palisading periosteal proliferation along it
Dx? ** = ? (R maxilla oblique)
Maxillary periapical infection
** = Blunted tooth root contour (possibly fragment)
Shortened, widened periodontal space
Interrupted lamina dura
Sclerosis of surrounding alveolar bone
Dx? ** = ? ((CT transverse @ M1)
Maxillary periapical infection
** = thickening of R maxillary bone
Features of periapical infection on CT?Interrupted lamina dura
Widened periodontal space, filled with ST-attenuating material
Widened pulp cavity
Maxillary sinus filled with ST-attenuating material
Thickening of maxillary bone
What’s going on here?
Proliferation of mucosal lining in maxillary periapical infection
Not just fluid!
(Left side normal)
Scintigraphy: what do hot areas represent?Alveolar bone (teeth appear as bright areas without uptake)
Dentigerous cyst aka?Dental ectopia
Heterotopic polydontia
Dental teratoma
Ear tooth
Dentigerous cyst
Development of dental material in an abnormal location, usually around base of ear (usually young) +/- associated discharging fistulous tract
Can be sx removed if problem
Dentigerous cyst (arrow = dental material)
Problem? possible complications?
Root fracture
Gas inclusion, ST attenuating tissue in maxillary sinus --> Tooth root abscess
What kind of image is this? * = ? @ = ?
Sagittal reconstruction of maxillary cheek teeth (old horse)
Maxillary sinusitis
* = ST-attenuating material in rostral maxillary sinus
@ = Air-filled caudal maxillary sinus
Wave mouth (severe, old horse)
How else can the TMJ radiographed?Special tangential projection
US of the TMJ: label dis
T = temporal bone
M = mandible
D = discus
P = parotid gland
Tranducer positions:
Best method of imaging TMJ?CT!
What is temporohyoid osteoarthopathy?Bony proliferation at the level of the jxn of the stylohyoid bone with the petrous temporal bone
Fusion & traumatic fracture may occur
Best method of imaging temporohyoud osteoarthopathy?CT
Temporohyoid ostoarthropathy
Thickening of styloid bone on left side, envelop temporo-hyoid articulation
How are the ears imaged?Tympanic bulla partially imaged radiographically
Middle & inner ear: CT/MRI methods of choice
What is PTB? Arrows? (CT transverse bone window)
Petrous temporal bone
Arrows = tympanic bullae
What structure? (CT transverse)
Guttural pouches
What’s going on?
Abnormal fluid in the guttural pouch
Pus: eroding retropharyngeal abscess
Hge: Erosion of internal carotids (fungal- aspergillosis; trauma- skull frax)
Guttural pouch tympany
Abnormal gas distention, causing compression of pharynx
Inflammatory debris after chronic empyema
How are the eyes imaged?Ultrasound useful for eyes & adnexa
A & P chambers, lens, ciliary apparatus: linear freq transducer
Transpalpebral & direct corneal techniques: LA & sedation
Retrobulbar space
Mass in anterior chamber of left eye. NORMAL right eye
Most common location for neoplasia in horses =HEAD!
Types of tumorsSCC
Dental tumors (adamantinoma, ameloblastoma, ameloblastic odontoma)
Appearance of adamantinoma (dental tumor)?Foamy ST opacity
Appearance of ameloblastoma (dental tumor)?Radiolucent/ST opacity
Internally divided
Appearance of ameloblastic odontoma (dental tumor)?Derived from enamal organ (embryolocial tooth precursor)
Mostly dental opacity
YOUNG horses
Osteoma: how does it behave? looks like?Benign, slow growth, may become very large
Smooth outline, bone opacity
Adenocarcinoma: where do they occur? in who? behavior?Frontal sinus & nasal cavity of OLDER horses
Very destructive, rapid growth