Overview of Temporoparietal Fascia Flaps
The Temporoparietal Fascia Flap (TPFF) is a type of surgical procedure commonly used in repairing deformities in the skull and face area. The TPFF is versatile and can be used in many different ways. For instance, it is often used to repair areas of the scalp, ear, facial tissues, eye socket, mouth, and nasal cavity, as well as defects at the base of the skull.
If needed, the TPFF process can also include the scalp tissue, making it a unique choice for repairing areas where hair growth is essential. Besides, if a more substantial reconstruction is required, the TPFF can be combined with muscle from the temporal region of the head or nearby skull bone.
Moreover, the TPFF procedure can also be performed with a free microvascular anastomosis. This means that the TPFF can be used for extensive reconstructions of the hands and feet. These operations involve connecting small blood vessels to restore blood flow and save the target tissues.
Anatomy and Physiology of Temporoparietal Fascia Flaps
To better the chances of successfully removing a patch of tissue called a temporoparietal fascia flap, doctors need to have a clear knowledge of the related body structure. When they’re operating, they can come across several layers of tissue, from the outermost to the deepest one:
- Skin
- Subcutaneous tissue (the layer just underneath the skin)
- Temporoparietal fascia (inside which they might find a muscle known as the temporoparietalis muscle)
- Loose areolar tissue (a type of connective tissue that acts like our body’s packing material)
- The surface layer of the deep temporal fascia (a protective layer around a muscle at the side of our head called the temporalis muscle)
- Temporalis muscle (a muscle at the side of our head, used for chewing)
- The deep layer of the deep temporal fascia
- Pericranium (a membrane that covers our skull)
- Bone
The temporoparietal fascia, also called the superficial temporal fascia, is a thin layer of connective tissue found under the skin’s fatty layer and above the fascia of the temporalis muscle. This tissue is linked with the galea aponeurotica (a tough fibrous tissue over the top part of our skull) and the superficial musculoaponeurotic system of the face (fibrous sheets under our facial skin), which are situated below the cheekbone.
The blood supply to this area is mainly via the superficial temporal artery (STA), a big artery that is positioned within the flap tissue. The STA splits above the cheekbone into many smaller branches, which further interconnect with the small blood vessels that fill the pericranium. The STA also gives rise to the middle temporal artery, responsible for supplying blood to the temporalis muscle. During the process of removing the temporoparietal fascia flap, the surgeon may also remove the tissue around the temporalis muscle, provided these two arteries are carefully preserved.
It’s important to note that, during the procedure, the surgeon needs to be careful about the anterior/frontal branch of the STA. If it’s damaged, it can affect the frontotemporal branch of the facial nerve leading to symptoms such as drooping of the eyebrow and temporary paralysis of the forehead on the affected side. To avoid this, doctors can use various anatomical landmarks to pinpoint the location of this nerve.
Why do People Need Temporoparietal Fascia Flaps
Temporoparietal fascia flap (TPFF) transfer is a tactic used often in reconstructive surgeries on the head, neck, hand, and lower extremity. The Temporoparietal fascia is a thin layer of tissue in the region of the head. This flap (a piece of tissue) can be moved to other areas and used to repair or replace damaged or missing tissue. Depending on what needs to be fixed, the TPFF can be used as a pedicled flap (the tissue remains connected to its original blood supply), a composite flap (combo of different tissue types, sometimes even including bone), or a free tissue flap (completely detached and transplanted to a new area).
The thin nature of TPFF makes it a great choice for fixing defects like in the skull base, facial tissues, nasopharynx (the area of your throat behind your nose), oral cavity (mouth), orbit (eye socket), ear, and scalp.
The TPFF transfer is often used to reconstruct the outer part of the ear in cases of microtia, a condition where the ear is underdeveloped. It is used whether the surgery uses cartilage from the patient’s ribs or special plastic implants. The TPFF is also frequently used to fix reconstructions if they are damaged by injury or infection.
It has many uses in surgery on the neck and head, such as acting as a barrier between the parotid gland (a salivary gland) and the skin to reduce symptoms of Frey syndrome (a condition that causes flushing and sweating on the cheek). It is used to fill the gap left after the transfer of a muscle in the temple region or after removing the parotid gland.
In hand surgery, the thin and flexible nature of the TPFF is perfect for making sure tendons (the tissues connecting muscle to bone) can easily move within the hand and fingers. This makes the flap a top choice for reconstructing parts of the hand.
When a Person Should Avoid Temporoparietal Fascia Flaps
There are several factors that doctors need to think about before doing a procedure called a temporoparietal fascia flap transfer:
Firstly, the doctors need to think about how far the flap can reach. This is because when the flap is attached, it can only reach certain parts of the body.
Next, it’s important for the doctor to remember that previous radiation treatments might have changed the small blood vessels in the flap. This can increase the chances of the procedure not being successful.
Lastly, past injuries or surgeries, or even just minor procedures (like a biopsy for a condition called “temporal cell arteritis”) might have interrupted the blood supply to the flap. This can also make the procedure less successful.
Equipment used for Temporoparietal Fascia Flaps
Before the Surgery
Your doctor might use a surgical marker to mark the specific location on your body where they’ll be operating. You’ll also be given local anesthesia which is a type of pain relief that numbs a specific area of your body, allowing the doctor to perform the surgery without you feeling any pain.
They will also use a topical antiseptic, which is a substance used to kill bacteria and other germs on your skin before the operation starts, to help prevent any infections. Depending on your condition, the doctor might use a corneal shield for protection of your eye. During some surgeries, a facial nerve monitoring system is used but this is not always the case.
During Surgery
The doctor will have a variety of tools on hand during the operation. This includes a tray that holds all the necessary equipment for head and neck soft tissue surgeries. They would use a bipolar cautery, a medical device that uses electricity to stop bleeding. A scalpel with a number 15 blade will be used for cutting tissue.
The surgeon will also have multiprong retractors, which are tools used to hold back the skin or other tissues to make it easier to operate. A closed suction drain with a bulb can be used to remove any build up of blood or other fluid from the surgical area. The doctor will close the scalp skin after the surgery using either sutures (stitches) or staples, depending on their preference.
After Surgery
After the surgery is done, antibiotic ointment will be applied to the wound to help prevent any possible infection. The doctor will cover the wound with dressing material to keep it clean and help it heal better. The dressing material used will depend on what your surgeon prefers.
Who is needed to perform Temporoparietal Fascia Flaps?
A group of healthcare specialists work together when you have surgery. The main person in charge of the operation is called the surgeon. They are special doctors who are trained to do surgeries. A surgical assistant supports the surgeon throughout the operation. They ensure that everything runs smoothly and assists the surgeon as needed.
There’s also the surgical scrub technician. This is a healthcare professional who helps the surgeon by passing them the instruments they need during the procedure. They are sometimes referred to as scrub nurses because they are responsible for maintaining a clean and safe operating environment.
A circulating or operating room nurse is another key member of the surgical team. This nurse moves around the operating room, checks the equipment, and provides what the surgeon and scrub technician need during the surgery.
Finally, you have the anesthesiologist or nurse anesthetist. They are responsible for giving you the medicine that makes you sleep (anesthesia) during surgery. They monitor your vital signs to make sure you are doing okay while you are asleep and ensure you do not feel any pain during the procedure.
Preparing for Temporoparietal Fascia Flaps
Before surgery, doctors need to make sure the patient is healthy enough to be put under general anesthesia. It’s important for them to thoroughly examine the patient’s head and neck, paying special attention to the functioning of the facial nerves.
They may also take photographs before surgery to remember the exact shape, size, and position of the area they are going to operate on. Patients should be thoroughly informed about the pros and cons of the procedure, along with any other options they might have. It’s especially important that doctors explain the possible risks of this specific procedure, which can include hair loss, weird sensations, facial nerve injury, besides the more common surgery-associated risks like pain, bleeding, infection, and scarring.
When it comes to making the incisions, the surgeon must ensure to cut the skin in such a manner that the hairline is preserved as much as possible. They are usually cut into a Y or T shape along the course of the superficial temporal artery (STA), a blood vessel located about 3 centimeters above where your ear joins your head.
While operating, doctors identify key anatomical features which include the STA and the path of the frontotemporal branch of the facial nerve. They prefer to perform the operation under general anesthesia and try to avoid using long-lasting paralytics as they want to keep monitoring the facial nerve during surgery. Some doctors might prefer not to use local anesthesia as it could interfere with nerve monitoring. They instead use a mixture of plain epinephrine to ensure vasoconstriction, which reduces bleeding.
Lastly, a single dose of antibiotics that cover skin-dwelling bacteria is given before the operation to prevent potential infections.
How is Temporoparietal Fascia Flaps performed
During this surgical procedure, it’s not absolutely necessary to remove any hair, although it can be helpful to remove hair about 1 to 2 cm around where the surgeon plans to make the cut.
1. The surgeon will plan an incision that looks like a Y or T. This is done in the crease in front of your ear and goes several centimeters upward. Some surgeons might choose to make the vertical part of the cut in a zigzag pattern. This helps hide the scar after surgery.
2. The cut goes through the skin, the dermis (second layer of skin), and the fatty layer beneath the skin. The surgeon then pulls up the skin of the scalp right below the level of the hair follicles (the part of the skin where hair grows out of). This is a very important step. It helps the surgeon keep the right depth during dissection and makes sure that the flap of skin used in the later portion of the surgery is the right thickness. The surgeon prefers to use a scalpel (a surgical knife) to avoid damaging the hair follicles from heat and reduce the risk of hair loss.
During this process, the surgeon needs to avoid damaging the underlying superficial temporal artery, a blood vessel that runs through the flap of skin. Once the surgeon has exposed enough of the flap, they can then make a cut around the edge, making sure to preserve its blood supply. At this point, the surgeon will tie off the smaller branches of the superficial temporal artery. The surgeon then rotates (or moves) the flap to cover the defect (area being treated). If the area needs skin that can grow hair, the surgeon might also include a piece of the overlying skin.
It’s important to be careful during this part of the procedure to avoid damaging the frontotemporal branch of the facial nerve, which lies under or within the thick layer of tissue called the temporoparietal fascia. However, the common approach of conducting the procedure under the scalp that grows hair means that the chances of inadvertently damaging the frontotemporal branch of the facial nerve is not likely.
The superficial temporal artery can also be followed more deeply until the middle temporal artery is found. In some situations, the surgeon may need to work in the parotid gland (a saliva gland located near your ear) to do this. At this point, the flap can be harvested as a ‘chimeric flap’. This means that it can include layers from the deep temporal fascia and/or the temporalis muscle (a muscle on the side of the head). If the surgeon wants, the procedure can be extended beyond the temporal fossa (a depression on the side of the skull) to include the pericranium (the membrane that covers the outer surface of the skull) and/or take a piece of the outer layer of the skull with its own blood supply. The flap can be rotated or tunnelled into the defect, or the blood vessels can be tied off in preparation for a free microvascular reconstruction surgery of distant defects. A drain might be placed to remove fluids from the area after the surgery. The skin flaps are then joined back together with sutures that eventually dissolve, followed by staples or stitches on the scalp.
If a portion of the scalp called the TPFF, not along with the scalp, is used to fix a defect, a skin graft might be placed on top of the TPFF. This could be done, for instance, during auricular reconstruction or surgery to rebuild the ear.
Possible Complications of Temporoparietal Fascia Flaps
After getting a temporoparietal fascia flap surgery, which is a procedure to restore tissues, you could possibly face certain complications. These problems can include:
* Alopecia (which is a medical term for hair loss)
* Flap necrosis (death of transplanted tissue)
* Facial muscle weakness after an injury to the facial nerve that controls forehead and eyebrow movements
* Venous congestion (accumulation of blood in the veins)
* Wound breakdown (where the surgical wound reopens)
* Hematoma (a collection of blood outside of the blood vessels) formation
* Infection
* Unfavorable scarring
* Paresthesia (unusual skin sensations like tingling or numbness)
However, most of these complications can be avoided if the surgeon is very careful during the procedure and pays special attention to the structures of the scalp. The chance of losing part or all of the transferred tissue (flap) is about 2.44%. About 8% of patients might experience some degree of hair loss. The chance of causing weakness or paralysis due to an injury to the facial nerve can be from 1% to 20%.
What Else Should I Know About Temporoparietal Fascia Flaps?
A temporoparietal fascia flap is a common method used by surgeons who specialize in reconstructive (restorative) surgery. This technique provides a safe way to repair or rebuild both nearby and distal (far away) soft tissue defects, which are essentially damaged or irregular areas in the body’s soft tissue (like your skin, fat, muscles etc.)
This particular method is gaining recognition especially in the fields of head and neck reconstruction. Surgeons utilize it either as a pedicled flap (still attached to its original blood supply) or it can be harvested as a free flap (detached and moved) for reconstructing parts of the extremities like arms or legs.
The results from this type of procedure can be very rewarding, especially if performed by a skilled and knowledgeable surgeon. What’s more, there is minimal harm to the donor site (the area where the flap is taken from), with most patients and their surgeons often not noticing any significant loss in the soft tissue within the area around the temple (the temporal fossa).
