Breast Reconstruction: Microsurgery and Autologous Reconstruction

As the rate of contralateral prophylactic mastectomy in breast cancer patients increases, more women are seeking immediate bilateral breast reconstruction. What are the main indications of preventive mastectomy of contralateral breast?

BRCA1 or BRCA2 mutation positive.

In what percentage of patients is the TRAM flap not available for autologous breast reconstruction?

25%. This is secondary to history of abdominal surgery or inadequate bulk of abdominal tissue.

What are the three well-described risk factors for microsurgical breast reconstruction?

Smoking, obesity, history of radiotherapy.

What important factors should be considered when deciding between implant based versus autologous breast reconstruction?

Patient’s desires, medical condition, body habitus, and possibility of additional adjuvant therapy.

What is the dominant blood supply to the free TRAM flap?

Deep inferior epigastric vessels.

What are the four main functions of the rectus abdominis muscles?

The rectus abdominis muscles are involved in the first 30 degrees of lumbar spine flexion, stabilize the upper body, provide the site of insertion for the oblique and transversus abdominis muscles, and assist in raising intra-abdominal pressure.

What other muscles are involved in torso flexion?

Iliopsoas muscles (strongest upper body flexors) and the vertically oriented fibers of oblique muscles (lesser role).

What is the “usual” relationship between the DIEA (deep inferior epigastric artery) perforators and the SIEA (superficial inferior epigastric artery)?

Inverse relationship; when the DIEA perforators are large or abundant, the SIEA is usually small and vice versa.

How much abdominal wall fascia is taken with the SIEA flap?

None.

Where does the SIEA pierce the Scarpa’s fascia and then run superficially?

Inferior to and within 1cm of the midpoint of the inguinal ligament.

Is the SIEA usually deep or superficial to Scarpa’s fascia BELOW the inguinal ligament?

Deep.

Is the SIEA usually deep or superficial to Scarpa’s fascia ABOVE the inguinal ligament?

Superficial.

How do you design an SGAP (Superior Gluteal Artery Perforator) flap?

The flap is designed along a central axis formed by origin of the SGA at 5 cm inferior to posterior iliac spine and the dome of maximum lateral fullness. Dissection is carried over gluteus maximus from lateral to medial. The medial origin of the muscle is taken down to expose the pedicle.

What flap dimensions can be obtained with the SGAP flap?

1. Skin: width 6 to 13 cm

2. Length 20 to 33 cm

3. Pedicle length: 6 to 8 cm

Where are the perforators of SGAP flap found most frequently?

One-third of the distance on a line from the posterior superior iliac crest to the greater trochanter.

What is a substantial disadvantage of the SGAP flap?

Harvest requires prone or lateral repositioning during surgery.

Can the SGAP flap be sensate?

Yes, by the repairing the dorsal branches of the lumbar segmental nerves to the T4 intercostal nerve.

Lateral septocutaneous SGAP flap was introduced to address the short pedicle length which is one of the limitations of traditional SGAP flap. What are the two muscles that the superolateral perforator comes through?