MUSCULOSKELETAL Flashcards
What is the physiological response of bone to injury?
A: Increased turnover, which can be imaged with bone-seeking radiotracers.
What is the most common bone-seeking radiotracer used in South Africa?
A: 99mTc Methylene Diphosphonate (MDP).
Which PET agent is used for bone imaging?
A: 18F Sodium Fluoride (18F NaF).
Which PET agent is used for bone imaging?
A: 18F Sodium Fluoride (18F NaF).
: What processes increase during bone remodeling?
:
Increased blood flow.
Increased extraction of ions onto the bone.
Increased binding of ions to hydroxyapatite crystals.
What are the conditions in which 99mTc MDP is commonly used?
A
Osteoblastic bone metastases.
Osteomyelitis.
Name a radiotracer specific for bone infection imaging.
A: 99mTc-labeled white blood cells.
Why can inflammatory and cancer cells be imaged using 18F FDG?
.
A: Because they have a high number of glucose transporters and increased hexokinase activity.
What are the four methods of tumor cell transport to the bone?
Hematogenous route (venous or arterial).
Lymphatic route.
Direct spread (e.g., sternum in breast cancer).
Intra-spinal route.
Which route is most common for hematogenous spread of bone metastases?
A: Venous route through Batson’s vertebral plexus.
What are the characteristics of Batson’s vertebral plexus?
Thin-walled veins.
Low intraluminal pressure.
Valveless veins.
Intercommunicating system.
What are the patterns of bone response to metastases?
Bone resorption (increased osteoclastic activity or tumor destruction).
Bone formation (reactive).
What are the types of bone metastases?
Osteolytic (e.g., renal, adrenal, acute leukemias).
Osteoblastic (e.g., prostate, neuroblastoma).
Mixed (e.g., lung, breast cancer).
Where does osteomyelitis commonly occur, and why?
A: In the metaphysis of long bones due to:
Rich and sluggish blood flow.
Porous bone structure.
: What is sequestrum in osteomyelitis?
A: Necrotic bone formed when blood supply to the bone is impaired.
What is involucrum in osteomyelitis?
A: New bone formed around the infection.