Benign vs. Aggressive Lesions

Question 1

Bone normal response

Answer 1

@ skeletal maturity bone continues to remodel
Resorption = production

Question 2

Wolff’s law of bone response

Answer 2

Every change in the form/ function of bone → changes in internal structure
(correlation between changes in structure and stress applied= sports)

Question 3

Diseased bone

Answer 3

Local imbalance between bone production and bone removal
Too much bone production= formation/ osteosclerosis
Too much bone removal= lysis (osteolucency)

Question 4

How do you classify benign or aggressive lesions?

Answer 4

Based on appearance of osteolytic/ osteoproliferative response
Look @ cortical destruction, pattern of bone lysis, zone of transition, periosteal reaction/ proliferation

Question 5

Benign rad changes

Answer 5

Chr., degenerative, slow process

Question 6

Aggressive rad changes

Answer 6

Active, ongoing and rapid process

Question 7

Geographic patterns of lysis

Answer 7

Well marginated
Least aggressive, benign
Cortex may expand (thin) but not destroyed

Question 8

Moth-eaten lysis

Answer 8

Aggressive
Discrete areas of lysis of variable size
Cortex may or may not be lytic

Question 9

Permeative lysis

Answer 9

Most aggressive
Focal areas of ill-defined osteolysis

Question 10

Lysis

Answer 10

Loss of 30-50% of bone mass is needed before lysis is seen on rads
Focal lesions require less bone loss to be seen
Generalized bone loss more difficult

Question 11

Pencil point rule

Answer 11

Easy trace → inactive (smooth, lamellar proliferation)
Irreg line → active (palisading proliferation)
Very irreg → active (spiculated prolif, amorphous new born formation)