Scalp & Calvarial Reconstuction Flashcards
Describe the vascular supply to the scalp
- Superficial temporal artery
- Occipital artery
- Supratrochlear
- Supraorbital
- Posterior auricular
Describe the anatomy of the STA
- terminal branch of ECA
- supplies largest territory on lateral scalp
- becomes subcutaneous above tragus
- travels within the TPF
- divides into anterior and posterior branch 2cm above arch
Describe anatomy of occipital artery
- branch of ECA
- enters scalp 2cm from midline at superior nuchal line (occipital protruberance)
- divides into medial and 2 lateral
Describe anatomy of STA and SOA
- both branches of ICA, ophthalmic
- STA located inline with medial canthus
- SOA located inline with medial limbus
- SOA exits SOforamen
- both travels superficial to frontalis muscle
Describe anatomy of scalp and temporal region
Skin
Subcutaneous layer - cnotains vessels just above galea, nerves, lymphatic
Aponeurosis - Galea-frontalis-occipitalis-TPF
Loose areolar layer - contains emissary veins connecting to intracranial venous sinuses = becomes parotidomasseteric fascia
Pericranium - derives blood supply from middle meningeal and intracranial vessels = becomes deep temporal fascia
Describe the sensory innervation of the scalp
All 3 branches of trigeminal, cervical spine and plexus
1- V1 (Supraorbital) - deep branch pierces pericranium and travels laterally until 1cm medial to STline, it pierces galea and supply frontoparietal scalp
- superficial branch pierces frontalis and supplies anterior forehead/hairline
2- V2 (Zygomaticotemporal) - temporal region
3- V3 (ATN) - temporal region
4- Greater and lesser occipital n - posterior scalp
5- Greater auricular n - posterior ear/lobule
Describe the cours eof the frontal branch
- at level of Zarch, CN branch courses in loose areolar plane=parotidomasseteric fascia
- continues to travel superficial and will be just below TPF/SMAS at 2cm above the arch
- approaches frontalis and innervates from beneath muscle
Describe anatomic layers of calvarium
- Outer table
- Diploe
- Inner table
- Epidural space
- dura mater
- Subdural space
Note: Parietal and occipital bone is thickest, temporla thinnest
How do you classify scalp defects?
- Congenital vs Acquired
- Partial vs Full thickness
- Size (subtotal vs total)
What is your DDX for a scalp defect?
Congenital
- Cutis Aplasia (absence of skin)
- Ectodermal Dysplasia (absence of hair/nail/teeth)
- Conjoined twins
Acquired
- Trauma
- Infection
- Burn
- Iatrogenic (Post-op post RTX)
- Androgenic alopecia
- Post skin cancer resection
Describe your goals of scalp reconstruction
- debridement
- maintain hairline
- reconstruct like w like ie. hairbearing tissue
- stable durable coverage of calvarium
Describe management of scalp defect according to size
<3cm : 1’ closure (with galea scoring as needed)
3-6cm : local flap (rotation, advancement, pin-wheel, 3rhomboid, bilobed, pinwheel, tissue expansion
6-10cm: large rotation flap, bucket handle, Orticochea 3flap, tissue expansion, subtotal scalp flap
>10cm : pericranial flap +STSG, free flap
Describe your management plan according to partial vs full thickness defect
PARTIAL
- STSG and plan 2’ recon if hair missing
FULL THICKNESS
- Outer table removal and STSG
- Pericranial flap + STSG - flap based on named art
- Local flaps with galeal scoring
- pinwheel, 3adj. rhomboid, rotation (<6cm)
- Orticochea, bucket handle (6-10)
- Subtotal scalp flap rotation and graft donor (>10cm)
- Tissue Expansion then local flap
- Distant pedicled flap
- Microvascular flap
Describe the orticochea flap
Used for occipital defect
3 flaps are raised in subgaleal plane and scored
1 large + 2 smaller, where width of 2smaller is 1/2 that of 1’ defect
If defect lateral to midline, larger flap is based contralaterally
Not for vertex defects
Name distant pedicled flaps for scalp defect recon
- pectoralis major (mastoid region defect)
- trapezius (occipital region defect)
- lat dorsi (temporal/periorbital
Describe the Juri flap
- For anterior hairline defects
- based on parietal (posterior branch) of STA
- temporoparietal region flap - needs delay procedure to reduce risk of tip ncerosis and maintain length on narrow pedicle
