**Region:** Head and Neck # Temporoparietal Fascia Flap ## Anatomy - Pedicle: named artery (typical diameter/length if present), venae comitantes; course from origin to flap/skin paddle; perforator pattern (number, location, intramuscular vs septocutaneous), choke vessels/adjacent angiosomes. - Vascular pedicle: superficial temporal artery (STA) with accompanying superficial temporal vein(s) (STV) running on/within the temporoparietal fascia (TPF) (Blondeel; Shokrollahi; Sharaf). - Mean arterial caliber and length reported: arterial caliber approximately 1.5–2.0 mm; mean arterial pedicle length ≈ 4 cm measured in the proximal pedicle specimens (Shokrollahi, Ch. 46). - Mean venous caliber and length reported: venous caliber approximately 2.0–3.0 mm; venous length ≈ 4 cm (Shokrollahi, Ch. 46). - STA course: arises from the external carotid, courses through the parotid region then becomes superficial anterior to the tragus, pierces the temporoparietal fascia just anterior to the tragus, runs tortuously in the preauricular area and bifurcates into frontal (anterior) and parietal (posterior) branches about 1–3 cm (variously reported 1–3 cm; 2–3 cm) above the zygomatic arch (Blondeel; Shokrollahi; Sharaf). - Pedicle measurements/technical points: the pedicle pivot point is at the preauricular fold/tragal region; reported pedicle length available for mobilization is commonly 2–4 cm from the tragus but can be extended proximally toward the parotid origin with careful dissection (Blondeel; Sharaf; Shokrollahi). Release of STA tortuosity may add ~1–2 cm of usable length (Sharaf). - Perforator pattern: the STA branches run directly within the fascial layer and give perforators that pierce the fascia to the overlying subcutaneous tissues/skin (type A axial fascial pattern). The point where STA branches become subdermal lies roughly two-thirds of the distance between zygomatic arch and midline; beyond that, subdermal plexus supplies scalp (Blondeel). - Choke vessels/angiosomes: extensive anastomoses exist between STA and occipital/posterior auricular arteries posteriorly and supraorbital/supratrochlear arteries anteriorly (Blondeel; Shokrollahi). These subdermal and fascial communications define the practical fascial vascular territory. - Nerves: sensory and motor branches relevant to flap harvest and sensate reconstruction. - Motor: frontal (temporal) branch of facial nerve crosses obliquely over the zygomatic arch in the loose areolar plane; its estimated surface trajectory (Pitanguy’s line) extends from ~0.5 cm inferior to the tragus to ~1.5 cm lateral to the superior brow. Dissection anterior/inferior to this line risks frontal branch injury (Blondeel; Sharaf). - Sensory: auriculotemporal nerve (branch of V3) lies posterior to the STA in the preauricular region and supplies sensory innervation to the temporal skin; it may be preserved or included if a sensate flap is desired (Blondeel; Shokrollahi). - Included tissues: skin/subcutaneous/fascia/muscle; thickness profile; arc of rotation; common variants/anomalies. - Tissue included: the TPFF is a single thin fascial layer (temporoparietal fascia) lying directly beneath the hair follicles, separated from deep temporal (temporalis muscle) fascia by an avascular loose areolar plane. It can be elevated alone (fascial), with overlying hair-bearing skin (fasciocutaneous), with deep temporal fascia (bilayered), or as composite with outer table calvarial bone, temporalis muscle, galea or skin grafts (Blondeel; Shokrollahi; Sharaf). - Thickness: temporoparietal fascia thickness reported 2–3 mm (Sharaf) and overall TPFF thickness range 2–4 mm described elsewhere (Blondeel). - Flap size limits: commonly quoted safe dimensions up to 12 × 14 cm; average free flap size frequently ∼12 × 8 cm; extended designs up to 17 × 12 cm reported with progressively less reliable edges (Blondeel; Sharaf). - Arc of rotation: pedicled TPFF has a low/inferior arc of rotation with pivot at preauricular region allowing reach to ear, lateral forehead, temporal region, and—by tunneling—middle/upper face and oral cavity; can reach three levels of ipsilateral hemiface and oral cavity when rotated (Blondeel; Sharaf). - Common anatomical variants/anomalies: hypoplastic or anomalous STA course/diameter in congenital craniofacial syndromes (hemifacial microsomia, Treacher–Collins, Romberg), prior external carotid ligation/embolization or prior coronal incisions in STA territory may render flap unreliable (Sharaf; Shokrollahi). ## Dissection Steps 1. Positioning, markings, landmarks. - Position: supine, head supported and turned toward the contralateral side (horseshoe headrest or donut); slight reverse Trendelenburg to reduce venous congestion as needed (Blondeel; Sharaf). - Markings: - Palpate/mark STA anterior to helical root/tragus; trace STA course and its frontal/parietal branches with a handheld Doppler (Blondeel; Sharaf). - Mark superior temporal line (bony landmark) — superior limit where TPF becomes galea (Blondeel). - Mark Pitanguy’s line (trajectory of frontal branch of facial nerve) and plan dissection to remain posterior/superior to it (Blondeel; Sharaf). - Outline flap template on TPF (centered over parietal branch when used for auricular reconstruction) and plan skin incision (lazy-S/zag, horizontal, or zig-zag) to minimize scar alopecia. Note: T- or Y-shaped junctions have reported scar alopecia in up to 8% of patients (Sharaf). 2. Plane (suprafascial/subfascial), perforator identification (handheld/IO Doppler). - Skin/subcutaneous elevation: - Elevate thin scalp skin flaps just below hair follicles (suprafollicular) to avoid follicle injury; preserve subcutaneous fat on scalp flap to reduce alopecia (Shokrollahi; Sharaf). - Identify and cauterize small perforating vessels with bipolar cautery; avoid aggressive cautery near follicles to reduce alopecia (Sharaf; Shokrollahi). - Perforator identification: - Use handheld Doppler preoperatively to delineate STA and branches. Perforators from STA traverse the fascial plane into skin; the fascial pedicle contains the axial vessels (Blondeel). 3. Pedicle dissection: exposure, control, division; transfer/inset; perfusion checks. - Posterior-to-anterior fascial elevation: - Incise fascial margins after superficial exposure; elevate TPF off deep temporal fascia in the loose areolar (Merkel’s) avascular plane from superior temporal line toward the preauricular region (Blondeel; Shokrollahi). - Ligate anterior STA/frontal branch branches as needed at anterior flap margin (routine anterior branch ligation ~3–4 cm distal to parietal separation when indicated) (Blondeel). - Pedicle control: - Decide skeletonized pedicle for free flap or wide pedicle for pedicled transfer. If free transfer planned, dissect STA/STV under microscope, clip small branches, and prepare for microvascular anastomosis (Sharaf; Blondeel). - Careful bipolar coagulation recommended to maintain hemostasis without injuring pedicle; avoid unipolar cautery over TPF (Sharaf). - If additional reach required: consider more proximal dissection toward parotid origin (risk to facial nerve increases), release STA tortuosity to gain 1–2 cm length, or temporary removal of zygomatic arch for additional 1–2 cm reach for deep oral/maxillary defects (Sharaf). - Division and inset: - For pedicled transfer: rotate islanded fascial flap through a generous tunnel (ensure tunnel large enough to avoid compression on pedicle) or transfer over surface and inset; avoid drains compressing pedicle (Sharaf; Blondeel). - For free transfer: divide pedicle after heparinization/anesthesia team preparation; use papaverine topically/prior to division to counter vasoconstrictor effects if local epinephrine has been used nearby (Sharaf). - Perfusion checks: - Hand-held Doppler and clinical assessment (color, capillary refill) are the methods specified in these sources; transillumination demonstrates fascial vascular branching intraoperatively (Sharaf; Blondeel). No standardized implantable-monitoring schedule or formal algorithm provided in the cited chapters. 4. Donor-site closure techniques. - Hemostasis and layered closure: - Meticulous hemostasis; place suction drain (position drain away from vascular pedicle). Close deep layer with absorbable sutures and skin with running resorbable or staples as preferred (Sharaf; Shokrollahi). - Hair-bearing closure considerations: - When hair-bearing scalp is included, limit flap width to permit primary closure (2–4 cm donor width often cited for primary closure); otherwise consider tissue expansion preop or allow secondary healing/skin grafting. Tissue expanders are an option to increase flap territory and facilitate closure (Blondeel; Shokrollahi). - Avoid alopecia: - Preserve hair follicles and minimize cautery; when possible leave subcutaneous fat on scalp flaps and use bipolar rather than unipolar cautery (Sharaf). ## Indications and Contraindications - Indications: - Pedicled TPFF: auricular reconstruction (microtia), coverage of cartilage/frameworks, lateral forehead/temporal/ear/cheek/orbit/skull base/dural coverage, palatal and oropharyngeal repair via tunneling, and brow/upper-lip hair-bearing transfer when skin paddle included (Blondeel; Sharaf; Shokrollahi). - Free TPFF: thin vascularized fascial coverage for extremity defects (dorsum of hand/foot), tendon gliding envelopes, vascular carrier for skin/mucosa/cartilage distant reconstructions (trachea, pharynx, larynx), vascularized calvarial bone composite flaps (Blondeel). - Use when thin, highly pliable vascularized tissue is required (TPFF among thinnest flaps available) (Blondeel). - Size limits: up to ~12 × 14 cm commonly harvestable; larger extensions possible but edge reliability decreases (Blondeel; Sharaf). - Sensate reconstructions: auriculotemporal nerve may be included to provide sensory innervation (Blondeel). - Contraindications: - Prior ligation/embolization of the external carotid artery or STA, prior coronal/scalp incisions within STA territory that have compromised the pedicle, radiation to the temporal scalp region (relative/absolute per context), or documented anomalous/hypoplastic STA in congenital craniofacial syndromes; additional imaging (Duplex/CTA) may be required for ambiguous anatomy (Sharaf; Shokrollahi; Blondeel). - Caution/relative contraindication when venous anatomy absent or severely compromised (Shokrollahi notes STV variability). ## Postoperative Care - Monitoring schedule/method: - Clinical monitoring and handheld Doppler assessment are the methods described for pedicled and free TPFF monitoring (Blondeel; Sharaf). No formal time-schedule specified in the cited chapters. - For donor site: drains placed and removed per routine once output minimal; drains positioned away from pedicle when pedicled flap used (Sharaf). - Warming, antithrombotic practice: - Specific systemic antithrombotic protocols are not detailed in the provided chapters. Papaverine topical use recommended immediately prior to flap division if local vasoconstrictor exposure suspected (Sharaf). - Positioning/splinting: - Avoid compression or kinking of pedicle—ensure tunnel is roomy and drains/closures do not compress the pedicle. Head positioning should avoid tension on pedicle (Blondeel; Sharaf). - Drains, mobilization, diet/analgesia: - Drain use and layered closure are described; routine postoperative mobilization and analgesia protocols are not specified in the cited chapters. - Return-to-OR thresholds and time windows: - The texts recommend clinical/Doppler verification of flow; if concern for vascular compromise exists, prompt assessment including return to the operative theater for re-exploration is implied but no timed algorithm is provided in these sources. For staged pedicled applications (e.g., ear reconstruction), pedicle division and inset are commonly performed after vascular inosculation is established—examples in similar staged flaps (paramedian forehead) used 3–4 weeks as a reference for pedicle division (other chapters), but TPFF-specific staged-timing is determined case-by-case in cited sources (Blondeel; Shokrollahi). ## Complications (rates & management) - Vascular complications: - Arterial spasm or small-vessel caliber (small vessel size and short pedicle cited disadvantages) can complicate microvascular anastomosis; topical papaverine recommended prior to division to mitigate spasm (Blondeel; Sharaf). No quantitative rates of thrombosis or loss provided in these chapters. - Venous anatomy variability (STV can be single, duplicated, posterior to artery, or absent) is noted; leaving a wider pedicle may assist venous drainage (Blondeel). No numeric venous-congestion rates given. - Flap loss/partial loss: - The cited chapters do not supply numeric frequencies for partial/total flap loss for TPFF; they emphasize anatomy-related risk factors (prior radiation/surgery, anomalous STA) and surgical technique to minimize loss (preserve perforators, maintain pedicle, avoid compression). - Infection/fat necrosis: - Not specifically quantified in the reviewed chapters. TPFF high vascularity described as favorable for coverage of infected or irradiated beds (Blondeel). - Donor-site issues: - Alopecia/scar alopecia: most common donor-site complaint; scar alopecia at T/Y incision junction reported up to 8% in one series (Sharaf; Shokrollahi). Prevention: preserve hair follicles, thin skin flaps, minimize cautery, avoid vertical scar tips when possible (Sharaf). - Sensory loss: injury to auriculotemporal nerve or deliberate inclusion for sensate flap may result in temporal/scalp sensory changes; loss of sensation over auriculotemporal distribution reported without specific frequency (Shokrollahi; Blondeel). - Brow ptosis: risk with injury to frontal branch of facial nerve; avoidance by staying posterior/superior to Pitanguy’s line is advised (Blondeel). - Temporal hollowing is not a principal issue for TPFF (more relevant to temporalis muscle flap) but composite harvests that include temporalis can cause contour changes (temporalis chapter). - Management algorithms: - Prevention: meticulous bipolar hemostasis, preservation of hair follicles, identification and preservation of critical nerves, Doppler mapping preop (Sharaf; Shokrollahi). - Vascular problem response options described in the sources are limited to immediate intraoperative measures (confirm flow with Doppler, irrigate/anastomose carefully, use papaverine for spasm). Formal algorithms (leeching, thrombolysis protocols, timed re-exploration windows) are not provided in these chapters; clinical suspicion should prompt urgent assessment and consideration of re-exploration per standard microvascular principles (sources do not itemize stepwise algorithms). ## Key Clinical Pearls - Mark the STA and its branches with handheld Doppler preoperatively and center the flap over the parietal branch for auricular work (Blondeel; Sharaf). - Stay posterior and superior to Pitanguy’s line (frontal branch course) — maintain a 2–3 cm safety margin posterior to the anticipated frontal-branch course at the zygomatic arch to avoid frontal-branch injury (Blondeel; Sharaf). - Elevation planes: raise thin skin flaps sub-follicularly to preserve hair follicles; elevate the TPF off the deep temporal fascia in the loose areolar (Merkel’s) plane for a quick, bloodless dissection (Blondeel; Sharaf). - Pedicle handling: the STA commonly bifurcates ~1–3 cm above the zygomatic arch; expect arterial caliber ≈1.5–2.0 mm and venous ≈2.0–3.0 mm. Skeletonize pedicle for free transfer under the microscope and clip small branches to maintain a bloodless field (Shokrollahi; Sharaf). - Gain extra length by releasing vessel tortuosity (can add ~1–2 cm) or by more proximal dissection toward the parotid origin, but proximal dissection increases facial-nerve risk (Sharaf). - When harvesting hair-bearing fasciocutaneous TPFF, limit donor width to allow primary closure (2–4 cm donor width typical) or plan tissue expansion preoperatively to avoid large grafts/secondary healing (Shokrollahi; Blondeel). - Use bipolar cautery sparingly at the skin edges and avoid unipolar cautery near the pedicle; for free transfers consider papaverine topically just prior to pedicle division if vasoconstrictor exposure suspected (Sharaf). - Anticipate venous-architecture variability: leave a wider base if venous drainage is a concern and verify STV position (it may lie up to ~3 cm posterior to arterial pedicle in some cases) (Blondeel; Shokrollahi).