1. Effects on adjacent surrounding structures
Site
Site
Size
Shape
Outline
Relative density
Effects on adjacent surrounding structures
Measuring the dimensions in cm
Describing boundaries
(the lesion extends from…..to…..in one dimension
and extends from…..to……in the other dimension)
Size

2. Monolocular/unilocular Multilocular Pseudoloculated Round Oval
Shape
Monolocuar
Monolocular/unilocular
Multilocular
Pseudoloculated
Round
Oval
Scalloped/undulating
Irregular
Pseudolocuar
Multilocuar

3. Outline Smooth * Well-defined Poorly-defined * Poorly-defined
Punched-out
Corticated: a thick or
thin surrounding RO line
Sclecotic: a non-uniform
RO boundary
Oval
Encapsulated
Irregular
* Well-defined
Well-defined
with a corticated
margin
Well-defined
without a corticated
margin
Poorly-defined
* Poorly-defined

4. surrounding structures
Effects on adjacent
surrounding structures
Bony expansion
Tooth displacement
3. Thinning of cortex
2. Displacement ID canal
Uniformly RL
RL with RO (mixed) RO
Relative density

5. Please describe the lesion
Question:
Please describe the lesion
as indicated by
yellowish arrow
There is a well-defined unilocular round shaped circumcoronal radiolucence with corticated margin over the submerged tooth 38 extending from left retromolar area down to the mandibular angle and from distal aspect of tooth 37 up to two/thirds of left ramus area, measuring approximately 3  5 cm in diameter.

6. A sequential approach to radiological interpretation
Panoramic radiography revealed the patient to be fully
edentulous. All bony outlines were within the normal range
except for a 4.5 x 3.0 cm well-demarcated, unilocular
homogeneous radiolucency with smooth well-corticated
outline in the left body of the mandible.
The lesion extended from the premolar region back to 1.5 cm
anterior to the posterior margin of the mandibular ramus.
There was slight expansion of the cortical outline of the lower
border in the left antigonial notch region.

7. A sequential approach to radiological interpretation
The adjacent mandibular canal was inferiorly displaced. Canal cortical outlines were intact with no evidence of resorption and the paranasal sinuses were clear.
A root fragment was noted in the region of the radiolucency in the left mandible, and there were several areas of the well-
delineated radiolucency in the left mandible was that of a benign cyst or tumor.

8. A sequential approach to radiological interpretation
Panoramic radiography also revealed a well-delineated
radiolucency rimmed by an ovoid 3.5 x 2.5 cm calcified
margin, superimposed over the left mandibular ramus.
The radiographic shadow of the calcified soft tissue lesion
extended superiorly to the level of the mandibular sigmoid
notch and 1.5 cm below the head of the left mandibular
condyle, and inferiorly to 1 cm below the left mandibular
foramen and lingula

9. A sequential approach to radiological interpretation
The principal differential interpretations were carotid
aneurysm and calcified lymph node.
Although carotid bruit was not clinically detected, the risk of
a carotid aneurysm mandated prompt investigation of this
radiographic finding.
To elucidate further the position of this calcified soft-tissue
lesion and the boundaries of the mandibular radiolucency, an
axial CT examination was performed.

10. A sequential approach to radiological interpretation
Axial CT
Maxilla
1st cervical vertebra
The CT confirmed the presence of the calcified-rimmed soft
tissue ventral and lateral of the first cervical vertebral body
and skull base.
This was interpreted as compatible with aneurysm or
psedoaneurysmal dilation of the internal carotid artery,
measuring as large as 2.4 cm.
Degenerative changes in the cervical spine were noted.

11. A sequential approach to radiological interpretation
Axial CT
Mandible, upper portion
Mandible, lower portion
Lower CT slices through the body of the mandible confirmed
the homogeneously radiolucent cystic lesion with a benign
appearance. There was evidence of buccal and lingual cortical
expansion with attenuation.
In view of the report of a probable carotid aneurysm,
CT angiography was prescribed to relate this lesion to its
surrounding structures.

12. A sequential approach to radiological interpretation
CT angiography revealed the calcified mass was intimately
related to tortuous internal and external carotid arteries.
Careful reformatting at various angulations failed to demonstrate a direct continuity between the internal carotid and the presumed aneurysm; however due to structural superimposition CT failed to provide a definite answer.
MRI was selected to elucidate further structures
obscured in the CT angiograms.

13. A sequential approach to radiological interpretation
MRI revealed bright signals for the carotid artery and jugular veins
bilaterally, but failed to demonstrate an aneurysm.
The contents of the lesion in the left mandibular body had intermediate signal intensity

14. A sequential approach to radiological interpretation
Angio MaxIP MRI revealed the carotids were found to be
tortuous. There was no evidence of an aneurysm of the left
internal carotid artier.
The surgeon wanted additional verification of the absence of
a carotid aneurysm and ordered ultrasonography.

15. A sequential approach to radiological interpretation
Ultrasound images showed no evidence of aneurysm. Both
carotid bifurcations were tortuous. There was evidence of
atherosclerotic plaque in the left and right carotid bifurcation
bulbs and the proximal region of the left internal carotid artery.
The systolic velocity ratio of right internal to common
carotid artery was 0.59 whereas the diastolic velocity ratio was
0.78; for the left side the respective ratios were 0.96 and 1.47.
These ratios are within the normal range.

16. Final Diagnosis A sequential approach to radiological interpretation
Mandibular lesion
Glandular odontogenic cyst
Neck lesion
The calcified lesion in the soft tissues adjacent to the first
cervical vertebra and extending to the carotid space was not
a carotid aneurysm, but rather a calcifying ‘cystic’ mass
probably representing a lymph node.

17. Your constructive comments are appreciated
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