Microsurgical reconstruction has transformed the management of complex head and neck defects, establishing itself as the gold standard for both functional and aesthetic reconstruction of hard and soft tissues [1]. The long-term success of these procedures hinges not only on the choice of an appropriate flap but also on the precise selection of recipient vessels for microvascular anastomosis [2]. Traditionally, vessels selected for oral and maxillofacial reconstruction are branches of the external carotid artery, such as the facial or superior thyroid arteries, and veins of the internal or external jugular systems, due to their predictable anatomy, calibre and proximity to the region [3,4].

However, these choices often require access to the neck, introducing additional surgical trauma, increased risk of complications, and extended operative time [5]. Particularly in patients with prior neck surgery, radiation therapy, or extensive oncologic resection, these vessels may be absent, fibrotic, or technically inaccessible, collectively described as the “vessel-depleted neck” [6]. In these challenging scenarios, the search for alternative recipient sites becomes critical to avoid compromising reconstructive success.

The superficial temporal vessels (STVs) have emerged as a valuable alternative, especially for reconstructions of the midface, scalp, or intraoral cavity, due to their favourable topographic position and relative preservation following prior neck treatment [6,7]. Their location in the preauricular region provides proximity to midface and craniofacial defects, allowing for the use of shorter flap pedicles and potentially reducing the need for vein grafts [4,8]. Moreover, their dissection avoids re-entry into scarred or irradiated neck fields, simplifying the surgical approach in select patients [3,9].

Nevertheless, temporal vessels are often underutilised in maxillofacial reconstruction, in part due to concerns about their variable anatomy, smaller diameter, and risk of vasospasm [7,10]. Some surgical teams may also be less experienced with temporal vessel exposure and anastomosis, further limiting their routine use [4,6]. However, cadaveric and anatomical studies have confirmed the superficial temporal artery’s consistent course, favourable dimensions, and suitability for microsurgical anastomosis [8,10].

This systematic review aims to collect and critically assess published evidence on outcomes of free flap reconstruction using temporal vessels. The goal is to clarify their clinical utility and define their role within modern reconstructive strategies for maxillofacial defects. By synthesising both qualitative and quantitative data on complication rates, flap viability, and recipient site morbidity, this review seeks to provide objective insight into whether the superficial temporal vessels can be considered a reliable and broadly applicable alternative, not only in salvage or vessel-depleted scenarios, but also as a first-line option in appropriately selected cases.

Protocol registration

This systematic review and meta-analysis was designed and executed following the guidelines of the PRISMA (Preferred Reporting Items for Systematic Reviews and Meta-Analyses) statement [11]. The research protocol was registered a priori in the international PROSPERO under reference number CRD420251061992.

The protocol can be accessed at: https://www.crd.york.ac.uk/PROSPERO/view/CRD420251061992

Focus question

The research question was structured according to the Population/Participants, Intervention, Comparison, Outcomes (PICO) framework to ensure a focused and transparent approach.

The focus question for this review was: “In patients undergoing maxillofacial reconstruction, what are the clinical outcomes of free flap surgery using STVs as recipient vessels?”.

Details of the PICO framework are summarised in Table 1.

Types of publication

Studies published in English that included data on patients undergoing free flap reconstructive surgery of the maxillofacial region with the temporal vessels as recipient vessels for the anastomosis were considered eligible for inclusion.

Information sources

The information source was the MEDLINE (PubMed), Scopus, and the Cochrane Library databases.

Types of studies

In this review, randomized controlled trials, controlled clinical trials, and prospective or retrospective cohort studies published from database inception to 19 January 2025 were included.

Population

Patients undergoing maxillofacial reconstructive surgery in which the STVs were utilised as recipient vessels.

Search strategy

An extensive search was conducted utilising the following algorithm: ((temporal anastomosis) OR (temporal vessels) OR (temporal artery) OR (arteria temporalis)) AND ((maxillofacial) OR (facial) OR (craniofacial) OR (head and neck reconstruction) OR (defect closure) OR (oral defect)) AND ((free flap) OR (microvascular) OR (flap reconstruction) OR (microsurgical) OR (tissue transfer) OR (vascularised tissue transfer) OR (fibula flap) OR (radial forearm flap) OR (rectus flap) OR (microvascular free flap))).

Inclusion criteria

Studies were considered eligible if they met the following criteria:

Exclusion criteria

Exclusion criteria were as follows:

Sequential search strategy

Titles and abstracts were screened independently by two reviewers (E.N.V. and N.E.K.), followed by a detailed full-text review based on the established eligibility criteria. Disagreements between the reviewers were resolved through discussion with a third author (C.S.). Additionally, the reference lists of included studies were manually reviewed to identify other potentially eligible articles for inclusion in the meta-analysis.

Data extraction and data items

Data extraction and tabulation were carried out by two independent authors (E.N.V. and C.T.) using a standardised, pre-designed table for data extraction. The data gathered included the following:

If any outcomes were missing due to incomplete reporting, only the available data from each study was used.

Quality assessment

The quality of the included studies was independently assessed by two reviewers (E.N.V. and N.E.K.) using validated tools tailored to study design. Discrepancies were resolved through discussion and consensus.

Single-arm studies were evaluated using the National Institutes of Health (NIH) Quality Assessment Tool for Before-After (Pre-Post) Study with no control group [12], which examines 12 domains related to study design, intervention delivery, outcome measurement, and reporting.

Comparative observational studies were appraised using the ROBINS-I (Risk Of Bias In Non-randomized Studies - of Interventions) tool [13], covering seven domains, including confounding, selection bias, classification of interventions, and outcome measurement. Based on the assessment of these criteria, each study was classified as low, moderate, or high risk.

Statistical analysis

Statistical analysis was performed using the R Project for Statistical Computing version 4.4.1 (The R Foundation; Vienna, Austria) [14]. The proportions of outcomes were determined by dividing the number of events by the total sample size for each study. To stabilize variance, a logit transformation was applied to the proportion estimates, and a random-effects model was employed to account for variability between studies. To ensure inter-rater reliability in the abstract screening process, Cohen’s kappa coefficient (κ) values were calculated. The analysis provided an overall prevalence estimate along with 95% confidence intervals, as well as heterogeneity statistics such as the Q statistic and I² value, which reflect the degree of variation across the studies. A forest plot was generated to visually display the individual study estimates and the pooled prevalence, aiding in the comprehensive interpretation of the results. The meta-analysis highlights significant prevalence rates and offers valuable insights into the occurrence of the outcomes, while also addressing the potential heterogeneity amongst the studies |included.

Study selection

The results were retrieved and selected for full text screening. A total of 1862 studies were initially provided through the systematic search and hand search of citations (n = 2). After removing 1834 duplicate records, two independent reviewers (E.N.V., C.S.) screened the titles and abstracts of the remaining articles (n = 28) to determine eligibility. Out of these, 27 studies met the inclusion criteria and proceeded to full-text review. In the end, data from 21 studies, involving 773 reconstructions performed on 759 patients, were included in the analysis [1,5-7,9,15-30]. The selection process is illustrated in Figure 1.

The level of agreement between the two independent reviewers (E.N.V. and C.S.) in the selection of abstracts was measured at κ = 0.87, indicating almost perfect agreement.

Exclusion of studies

A total of seven studies were excluded following full-text assessment. One study [31] was excluded because the full text was unavailable to the authors, and six studies [32-37] because relevant outcome data could not be extracted. No additional studies were excluded for reasons related to study design, patient population, or intervention type.

Study characteristics

The 21 included studies reported on a total of 759 patients who underwent 773 free flap reconstructions using the STVs as recipient vessels. Most were retrospective case series (n = 15) [1,5,6,15-19,21,23,24,26-30], followed by prospective series (n = 2) [9,25], and randomised controlled trials (n = 3) [7,20,22]. Patient age ranged from 2 to 99 years, with a predominance of male patients in most reports. The most common indications for reconstruction were oncologic defects, facial asymmetry, malformations, osteoradionecrosis, trauma, and other postoperative sequelae. Defects were most frequently located in the midface/orbital region, followed by the lower third/intraoral region, the upper third of the face, and less frequently the skull base and other sites. Where flap type was reported, the most commonly utilised were the anterolateral thigh flap (n = 105), radial forearm free flap (n = 80), fibula free flap (n = 43), latissimus dorsi flap, vertical rectus abdominis myocutaneous (VRAM) flap, scapula/parascapular flap, serratus flap, and others including deep circumflex iliac artery (DCIA), free groin, and gracilis flaps. Detailed per-study characteristics are provided in Table 2.

Risk of bias in included studies

Based on NIH Quality Assessment Tool for Before-After (Pre-Post) Study with no control group [12], four studies were judged at low risk of bias [17,18,20,29], the majority were considered at moderate risk of bias [1,5,7,15,16,22,25-28,30], while one study was rated as high risk of bias [24] (Table 3).

ROBINS-I tool [13] for comparative observational studies, showed that three studies were judged at moderate risk of bias [9,19,23], while two were rated as serious risk of bias due to confounding [6,21] (Figure 2 and 3).

Meta-analysis

The incidence of arterial thrombosis or compromise following anastomosis at the temporal vessels for maxillofacial reconstruction was observed in 1.44% of cases (95% CI = 0.39 to 5.24; I² = 0%) (Figure 4). Venous thrombosis or compromise occurred in 5.13% of cases (95% CI = 3.21 to 8.1; I² = 0%) (Figure 5). The overall rate of vascular compromise was 7.24% (95% CI = 4.43 to 11.62; I² = 0%) (Figure 6). Return to the operating theatre was required in 7.72% of patients (95% CI = 4.84 to 12.1; I² = 21%) (Figure 7). Another analysis included eligible studies to estimate the rate of successful flap salvage, which was 4.23% (95% CI = 2.47 to 7.15; I² = 0%) (Figure 8). Partial flap necrosis was reported in 2.14% of patients (95% CI = 0.76 to 5.87; I² = 0%) (Figure 9), while total flap necrosis occurred in 4.05% of cases (95% CI = 2.32 to 6.95; I² = 0%) (Figure 10). Complications at the recipient site was wound dehiscence, infection, haematoma, seroma, and postoperative facial nerve weakness were observed in 10.43% of patients (95% CI = 7.23 to 14.82; I² = 0%) (Figure 11).

In present systematic review and meta-analysis, we evaluated the suitability of the STVs as recipient sites for microvascular reconstruction in the maxillofacial region. Given their anatomical proximity to midface and cranial defects, as well as their relative preservation in previously treated necks, with the exemption of parotid primary lesions, STVs represent a potentially valuable yet underutilised option. This study aimed to clarify their role by synthesising published outcomes and providing quantitative estimates of complication rates, thereby contributing objective evidence to support their broader consideration in reconstructive planning.

The STVs offer a unique combination of anatomical, technical, and aesthetic advantages that make them attractive recipient sites in head and neck reconstruction. Their superficial and consistent course allows for easy identification under loupe or microscope, while incisions can be placed discreetly within hair-bearing or preauricular regions, avoiding visible cervical scars [28,38,39]. Their superficial location allows direct access without the need for deep dissection, and their anatomical position remains largely unaffected by head positioning in the intensive care unit, thus reducing operative time and minimising the risk of pedicle compression [7,10].

Temporal vessels are particularly advantageous in the context of the vessel-depleted or “frozen” neck, a surgically hostile environment characterised by fibrosis, scarring, distorted anatomy, and compromised vascular integrity following neck dissection and/or radiotherapy [6,40]. In such cases, conventional cervical vessels (e.g., facial, superior thyroid, external jugular) may be absent, fibrotic, or technically inaccessible, substantially increasing the risk of intraoperative complications and flap failure [7,24]. Temporal vessels lie outside these compromised surgical fields, offering an anatomical, unirradiated recipient bed that is usually distant from previous interventions [6,9]. This spatial separation simplifies dissection, exposure of the recipient vessels, and avoids the need for aggressive re-entry into irradiated or scarred areas, which have been reported to be prone to poor healing and infection [9,34]. Their consistent presence and preserved patency in previously treated necks has been confirmed in both retrospective case series and anatomical studies [3,4]. Moreover, in patients with extensive prior treatments, the STVs enable microvascular reconstruction without requiring long pedicles or interposition vein grafts, both of which are associated with reduced flap survival particularly in midfacial reconstructions, while STVs are also commonly used as recipient vessels for scalp defect repairs [41].

The vascular outcomes observed in this analysis affirm the reliability of the STVs in microvascular reconstruction. Arterial compromise occurred in only 1.44% of cases, while venous compromise was noted in 5.13%, yielding a total vascular complication rate of 7.24%. These figures are well within the acceptable range for head and neck free flap surgery, and comparable to series using traditional cervical vessels [42]. Notably, the low arterial thrombosis rate reflects the suitability of the superficial temporal artery for anastomosis, despite prior concerns regarding their smaller diameter and susceptibility to vasospasm [7,42,43].

Return to the operating theatre was required in 7.72% of patients, which aligns with reported re-exploration rates in large microsurgical series [9,22]. Importantly, the flap salvage rate reported in this study is over half of returning cases (4.23%), demonstrating that vascular events related to STVs are often reversible with timely intervention. This highlights the importance of early postoperative monitoring and supports the notion that STVs offer not only a viable but a clinically manageable recipient option in complex reconstructions. These findings are further supported by direct comparative studies. A prospective trial by Sousa et al. [7] found no statistically significant difference in total flap loss or overall complication rates between patients reconstructed using superficial temporal versus cervical vessels, reinforcing their equivalence in midface and scalp defects. Additionally, a recent meta-analysis that included comparative cohorts confirmed that temporal vessels offer comparable safety to neck vessels in terms of thrombosis and partial necrosis, validating their use in carefully selected clinical scenarios [42].

In addition to favourable vascular outcomes, the overall rates of tissue loss and recipient site morbidity in this analysis support the clinical safety of using STVs. Partial flap necrosis was observed in only 2.14% of cases, while total flap loss occurred in 4.05%. These rates fall within the expected range for complex reconstructions and are comparable to outcomes reported with cervical recipient vessels in similarly challenging oncologic populations [9,42,44]. Recipient site complications including wound dehiscence, haematoma, infection, and transient facial nerve weakness were recorded in 10.43% of patients. This rate is acceptable in the context of head and neck microsurgery and reflects the relatively superficial and well-vascularised nature of the temporal region [28]. Moreover, the avoidance of deep neck dissection and the ability to preserve cervical lymphatic structures may contribute to reduced surgical morbidity and improved patient recovery profiles [5,38].

Limitations

Despite these promising results, this study has several limitations. Most included data were derived from retrospective case series, often lacking standardised definitions, outcome measures, or long-term follow-up. Heterogeneity in flap types, defect locations, and institutional protocols as well as surgical competency of variable included surgical teams, may have influenced complication rates and limits the comparability between studies. Additionally, only a few sources offered direct comparisons between temporal and cervical recipient vessels in controlled settings, which restrict the strength of intergroup conclusions. Finally, patient-reported outcomes, functional assessments, and aesthetic satisfaction were inconsistently reported or absent, leaving important aspects of reconstructive success underexplored. Future prospective and multicentre studies with unified endpoints are warranted to validate and expand upon these findings.

This systematic review and meta-analysis supports the use of superficial temporal vessels as a reliable and effective recipient site for microvascular reconstruction of maxillofacial defects. Their consistent anatomy, surgical accessibility, and preservation outside previously treated cervical fields make them especially valuable in complex or salvage cases. The observed rates of vascular compromise, flap loss, and recipient site complications were comparable to those reported for conventional cervical vessels, indicating that temporal vessels are not only a viable alternative but may serve as a primary option in appropriately selected patients. These findings reinforce the need to reconsider the role of superficial temporal vessels beyond salvage settings and integrate them into standard reconstructive planning for midface, scalp, and upper facial defects.