2. Study of lucent bony lesion depends
on:1.structural modification.
2.periosteal reaction.
3.tumour matrix.
4.tumoural extension.
3. Structural modification
The bone reacts to any form of aggression
by either :
1.stimulation of osteoclasts ..leading to
osteolysis.
2.stimulation of osteoblasts..leading to
sclerosis.
4. Hence bony reaction to aggression can
be :
Lytic …
Sclerotic..
Or mixed.
5. Osteolysis
Analysis is based upon LODWICK criteria:
Type I :Geographical lesion .
Type II :moth eaten lesion ..
Type Iii :peremeative bony lesion.
7. Geographical bony lesion
Focal lesion ,well defined, rounded, lobulated or
polygonal
Can be divided to 3 sub types :
IA: sclerotic margins denoting slowly progressive
lesion (bone cyst ,NOF ,Fibrous dysplasia)
IB: well defined ,non sclerotic margins ,denoting
more rapid ,but still benign lesion (GCT,
Chondromyxoid fibroma).
IC :ill defined border denoting rapidly evoluting
lesion (Malignant or infectious)
8. Moth eaten lesion
Formed of small multiple bony lucencies
destroying the cortex .
Corresponds to either infectious or
malignant lesion .
9. Permeative lesion
Corticaldestruction by multiple bony
lucencies ,seen in tangential view .
Denoting a very aggressive process ..
Either malignant or infectious.
11. Mixed processes
Geographical osteolyis ,surrounded by
dense sclerosis:
Denotes slowly progressive lesion (osteoid
osteoma,Osteoblastoma or chronic
osteitis )
Complex ,disorganized lesion formed of
lytic and sclerotic areas almost always
with malignant or infectious pathologies
12. Periosteal reaction
Periosteal agression by a bony lesion (or
less frequently soft tissue lesion )leads to
osteogenesis from subperiosteal
osteoblasts .
Manifested 2-4 weeks after beginning of
the process.
13. :Types of periosteal reaction
1.Solid homogenous.
2.Remodelled reaction.
3.continuous-separate from the cortex(uni
or multi-lamellar).
4.Spiculated reaction (sun ray..brush
border)
5.discontinuous periosteal reaction.