Endoscope-assisted superficial parotidectomy of large benign parotid tumor through a retroauricular hairline–cranial auricular groove incision approach: A retrospective study

Abstract

Objective

To compare perioperative outcomes, complications, and cosmetic results between endoscope-assisted superficial parotidectomy via a retroauricular hairline–cranial auricular groove incision and a modified Blair incision for large benign superficial-lobe parotid tumors.

Methods

This retrospective study was conducted at a single tertiary center and included consecutive patients undergoing endoscope-assisted or modified Blair superficial parotidectomy (n = 96; 48 patients/group). The outcomes included operative metrics, conversion, complications (Frey syndrome and facial nerve palsy), and scar results assessed at approximately 3 months within the 3–6-month follow-up period using the Patient and Observer Scar Assessment Scale—Observer Scar Assessment Scale 5–50 and Patient Scar Assessment Scale 6–60, wherein lower scores indicate better results. Group comparisons were performed using appropriate parametric or nonparametric tests and χ² or Fisher’s exact test.

Results

All endoscope-assisted procedures were completed without conversion. Compared with the endoscope-assisted group, the traditional group had higher blood loss (56.3 ± 5.4 vs. 22.4 ± 6.7 mL), greater postoperative drainage volume (118.7 ± 21.5 vs. 58.5 ± 12.3 mL), and longer drainage duration (6.1 ± 1.1 vs. 3.4 ± 0.5 days; all P < 0.01). Furthermore, the operative time was longer and minor sensory events were fewer in the endoscope-assisted group (P < 0.05). No Frey syndrome or persistent facial nerve palsy was observed during the 3–6-month follow-up period. Overall, the Patient and Observer Scar Assessment Scale scores favored the endoscope-assisted group (both P < 0.01).

Conclusion

Endoscope-assisted superficial parotidectomy via a retroauricular hairline–cranial auricular groove incision may offer cosmetic advantages with fewer minor deficits compared with the modified Blair approach, at the cost of longer operative time. As an observational study with a modest sample size, these results should be viewed as suggestive and confirmed in larger prospective cohorts.

Introduction

Salivary gland tumors represent 6%–8% ¹ of all head and neck neoplasms, with approximately 75% of them being benign. ² The traditional Blair “S”-shaped incision used in parotidectomy offers adequate surgical exposure but results in visible scarring, causing significant psychological and esthetic distress for patients, particularly younger individuals who prioritize postoperative cosmetic results. Facial scarring not only impacts appearance but also creates social and psychological challenges, leading to a notable decline in the quality of life of patients. Consequently, the reduction of postoperative scarring while also ensuring complete tumor excision and preservation of facial nerve function has emerged as a crucial focus in advancing parotid tumor surgery.

Lin et al. ³ (2000) pioneered endoscope-assisted parotidectomy, revolutionizing the minimally invasive management of parotid tumors. The current endoscope-assisted parotidectomy techniques, such as cranial auricular groove incision, retroauricular hairline incision, and modified cranial auricular groove incision (inverted “V” incision) have certain limitations, mainly being suitable for small tumors in the posteroinferior parotid gland region.^4–8 These approaches are generally safe with favorable cosmetic outcomes for small benign tumors (≤4 cm) in the superficial lobe; however, they are inadequate for larger benign or suspected malignant tumors.^9,10 Endoscope-assisted resections of parotid tumors ≥5 cm with mild inflammatory adhesions are particularly challenging, complicating facial nerve dissection and increasing the risk of nerve injury. Conventional endoscope-assisted techniques face limitations in establishing the operative cavity, visual field, and operating space as well as ensuring facial nerve protection in such cases. Despite limited clinical studies on the endoscope-assisted management of larger parotid tumors, we propose a combined cranial auricular groove-hairline incision approach to address these challenges. This approach enhances concealment, connects incisions to create a wider tunnel and operative cavity, and improves the operating space and visualization.

This study is the first to merge the endoscope-assisted superficial parotidectomy technique with a retroauricular hairline–cranial auricular groove incision for removing large benign parotid tumors (≥5 cm) and comparing the outcomes with conventional open surgery. Our findings revealed potential benefits in preserving the facial nerve, improving esthetic outcomes, and decreasing postoperative complications; these observations require confirmation in larger prospective cohorts.

Materials and methods

Clinical data

In this retrospective study, 96 patients diagnosed with superficial parotid tumors who were treated at Suining Central Hospital between February 2023 and November 2024 were analyzed. The patients were categorized into two groups based on the surgical approach employed: endoscope-assisted group (comprising 16 males and 32 females, aged 44.0–56.0 years with a mean age of 48.2 ± 4.08 years) and traditional group (consisting of 20 males and 28 females, aged 42.0–58.0 years with a mean age of 50 ± 5.01 years).

All procedures involving human participants were conducted in accordance with the Declaration of Helsinki (1975), as revised in 2024. All patient details were fully deidentified prior to analysis and reported in line with the institutional policy. The reporting of this study conforms to the Strengthening the Reporting of Observational studies in Epidemiology (STROBE) guidelines for observational cohort studies. ¹¹

Eligibility criteria

The inclusion criteria were as follows: (a) benign superficial parotid tumors ≥5 cm in diameter; (b) absence of preoperative facial paralysis or severe local infection; (c) no history of facial/cervical surgery or radiation therapy; (d) provision of informed consent; (e) suitable physical condition for surgery; and (f) all procedures conducted by the same surgical team to maintain consistent technical standards.

The exclusion criteria were as follows: (a) suspected malignant parotid tumors based on preoperative imaging or fine-needle aspiration cytology; (b) tumors situated in the deep lobe of the parotid gland; (c) severe systemic diseases contraindicating surgical intervention; and (d) poor patient compliance.

Surgical technique

All patients underwent preoperative high-frequency ultrasonography or enhanced computed tomography (CT) examination to assess the tumor location, size, and its proximity to the facial nerve. Magnetic resonance imaging (MRI) was conducted when deemed necessary for supplementary diagnostic purposes. Surgical incisions were planned based on the imaging findings: a retroauricular hairline–cranial auricular groove incision for the endoscope-assisted group and a modified Blair incision for the traditional group. Preoperative skin preparation was extended to the retroauricular and temporal regions for the endoscope-assisted group. Routine preoperative assessments, including complete blood count, coagulation profile, and liver and kidney function tests, were performed on all patients to rule out any surgical contraindications.

Endoscope-assisted procedure

The patients were placed in the supine position under general endotracheal anesthesia, with the affected shoulder elevated and the head rotated approximately 45° toward the opposite side. An incision was made along the retroauricular hairline, extending to the cranial auricular groove anterior to the mastoid process. The incision length typically exceeded the maximum tumor diameter by 0.5–1.0 cm. A subcutaneous injection of normal saline with 1:100,000 epinephrine was administered along the incision line and flap area to reduce bleeding. The flap was raised along the lateral border of the sternocleidomastoid muscle to create the surgical cavity, with special attention given to preserving the great auricular nerve. Subsequently, the endoscope-assisted system was introduced, and an ultrasonic scalpel or electrocautery was used under 10–15× magnification to gradually expose the tumor and adjacent critical structures, focusing on identifying and safeguarding the facial nerve trunk and its branches. After complete tumor removal and confirmation of benign pathology through a frozen section analysis, a negative pressure drainage tube was inserted, and the incision was closed layer by layer.

Based on our clinical expertise, we have delineated the essential steps for performing endoscope-assisted parotidectomy through a retroauricular hairline–cranial auricular groove incision: (a) thorough preoperative imaging evaluation to ascertain the location and size of the ideal incision; (b) incision planning in accordance with the “concealment” principle, ensuring the inconspicuous placement of the retroauricular incision within the hairline and the cranial auricular groove incision concealed by the auricle; (c) elevation of the flap beyond the tumor margins for adequate visualization; (d) meticulous dissection under endoscope-assisted magnification, with a focus on identifying the facial nerve trunk; (e) implementation of a “distal-to-proximal” dissection strategy, safeguarding the peripheral facial nerve branches before progressing to the primary trunk; (f) precise hemostasis utilizing bipolar cautery and ultrasonic instruments; and (g) meticulous cosmetic closure to minimize scarring. This standardized surgical algorithm serves to mitigate complications and enhance the surgical outcomes (Figures 1 to 3).

Figure 1.

(a) Frontal preoperative photograph (eyes masked). (b) Lateral view. (c) Coronal CT showing a superficial-lobe parotid mass (arrow) with maximal diameter indicated and (d) retroauricular hairline–cranial auricular groove incision design. CT: computed tomography. All images were deidentified.

Figure 3.

(a) Resected specimen with metric ruler (longest diameter labeled). (b) Early postoperative scar concealed within the retroauricular hairline/auricular contour and (c) histopathology (H&E, 100×) consistent with the final diagnosis. H&E: hematoxylin and eosin.

Figure 2.

Working space and key exposure steps in the endoscope-assisted approach. (a) Insertion of the external retractor and creation of a gasless subcutaneous working space (parotid gland, great auricular nerve, and sternocleidomastoid identified). (b) Flap elevation along the subplatysmal plane to widen the cavity. (c) Early identification of the facial nerve trunk and (d) exposure of the temporofacial and cervicofacial divisions with instrument triangulation.

In the traditional approach, the patients were placed in the supine position under general endotracheal anesthesia, with the affected shoulder being moderately elevated and the head rotated approximately 45° toward the opposite side. A modified Blair incision was employed, running from the front of the earlobe along the posterior edge of the mandible to the crease of the cervical skin. Following the elevation of the skin flaps to reveal the parotid region, the facial nerve trunk was located, and dissection proceeded anteriorly for complete tumor removal. Subsequently, a negative pressure drainage tube was inserted postoperatively, and the incision was closed in layers.

Standardized operative workflow and adherence

This retrospective cohort was managed under a departmental standardized workflow to ensure consistent technical steps for both approaches. For the endoscope-assisted approach, exposure was obtained via a gasless subcutaneous working space maintained by external retractors/skin hooks, with a rigid 0°–30° endoscope for visualization. The key steps for this approach included early trunk identification, nerve-oriented dissection (distal-to-proximal), atraumatic counter-traction, and controlled energy use. A standardized two-operator setup was used: the assistant controlled the endoscope and provided suction and gentle counter-traction to maintain triangulation and a stable working space. The modified Blair incision approach followed our institutional standard with trunk-first identification and branch preservation.

For the modified Blair incision, exposure was obtained by subplatysmal flap elevation and self-retaining or handheld retractors; the assistant provided suction, gentle counter-traction, and nerve-hook retraction as needed during nerve identification and lobar dissection.

Scar assessment

Postoperative scars were evaluated using the Patient and Observer Scar Assessment Scale (POSAS) at approximately 3 months within the 3–6-month follow-up period. The Observer Scar Assessment Scale (OSAS) includes five items scored 1–10 each (1 = normal skin; 10 = worst imaginable scar); total 5–50, wherein lower scores indicate better results. The Patient Scar Assessment Scale (PSAS) includes six items scored 1–10 each: total 6–60, wherein lower scores indicate better results. Patients completed PSAS during follow-up; OSAS was scored based on standardized photographs by blinded reviewers. ¹²

Statistical methods

All analyses were performed using SPSS 27.0 (IBM Corp., Armonk, NY, USA). For measurement (continuous) data, distribution was assessed via the Shapiro–Wilk test (with Q–Q plots) and homogeneity of variances via Levene’s test. Normally distributed variables were reported as mean ± SD and compared between the two groups using the independent-samples (unpaired) Student’s t-test. Welch’s t was used when the variances were unequal, and the Mann–Whitney U test was applied when normality was violated. For count/discrete (categorical) data, the results were shown as n (%) and compared using the χ² test (or Fisher’s exact test if any expected frequency was <5). All tests were two-sided with α = 0.05. Analyses followed a complete-case approach (no imputation). Specifically, the operative time, blood loss, drainage volume, and drainage duration were compared using the independent-samples t-test (Welch’s t when variances were unequal); POSAS total scores (OSAS/PSAS) were compared using the Mann–Whitney U test. Categorical outcomes (mild oral commissure deviation, auricular numbness, Frey syndrome, and facial nerve palsy) were compared using the χ² or Fisher’s exact test, as appropriate.

Given the retrospective design, no formal sample size calculation was performed, and all consecutive eligible patients were included during the study period (n = 48 per group). This sample provided adequate precision for the observed between-group differences in key continuous outcomes (all P < 0.01), whereas very low-frequency complications were summarized descriptively.

Results

Pathological diagnoses in the endoscope-assisted group included pleomorphic adenoma (n = 32), Warthin’s tumor (n = 12), and basal cell adenoma (n = 4), while the traditional group included cases of pleomorphic adenoma (n = 24), Warthin’s tumor (n = 20), and basal cell adenoma (n = 4). The mean tumor diameter was 6.24 ± 0.64 cm in the endoscope-assisted group and 6.13 ± 0.53 cm in the traditional group. Statistical analysis revealed no significant differences between the two groups in terms of sex, age, tumor diameter, or pathological type (P > 0.05), indicating good comparability (Table 1).

Table 1.

Comparison of baseline clinical characteristics between the two groups.

Items	Endoscope-assisted group (n = 48)	Traditional group (n = 48)	P-value
Sex			0.673
Male	16	20
Female	32	28
Age (mean ± SD, years)	48.2 ± 4.08	50.0 ± 5.01	0.785
Tumor diameter (mean ± SD)	6.24 ± 0.64	6.13 ± 0.53	0.800
Pathological findings (cases (%))			0.675
Pleomorphic adenoma	32 (66.7)	24 (50.0)
Warthin’s tumor	12 (25.0)	20 (41.7)
Basal cell adenoma	4 (8.3)	4 (8.3)

Data are presented as mean ± SD for continuous variables and n (%) for categorical variables. Normality was assessed via the Shapiro–Wilk test and homogeneity of variances via Levene’s test. Group comparisons were performed using the independent-samples t-test (or Welch’s t/Mann–Whitney U test when appropriate) for continuous variables and the χ²/Fisher’s exact test for categorical variables. A two-sided P-value <0.05 was considered statistically significant. For multicategory distributions (e.g. pathology), omnibus χ² tests were applied.

In this study, 96 patients were enrolled, with 48 in the endoscope-assisted group and 48 in the traditional group. All patients in the endoscope-assisted group underwent successful endoscope-assisted superficial parotidectomy using a retroauricular hairline–cranial auricular groove incision without requiring conversion to open surgery.

Intraoperative visualization was adequate in all completed cases using the planned exposure strategy, and no procedure was converted due to poor exposure in the endoscope-assisted group. An analysis of the operative time in the endoscope-assisted group demonstrated a significant decreasing trend with increasing surgical experience.

A comparative analysis of the surgical parameters revealed that the operative time was significantly longer in the endoscope-assisted group (154.7 ± 28.5 min) than in the traditional group (125 ± 16.7 min, P < 0.05). However, the intraoperative blood loss (22.4 ± 6.7 vs. 56.3 ± 5.4 mL), postoperative drainage volume (58.5 ± 12.3 vs. 118.7 ± 21.5 mL), and drainage duration (3.4 ± 0.5 vs. 6.1 ± 1.1 days) were all significantly lower in the endoscope-assisted group (P < 0.01).

The incidence rates of mild oral commissure deviation (4/48, 8.3% vs. 20/48, 41.7%) and auricular numbness (8/48, 16.7% vs. 24/48, 50.0%) were significantly reduced in the endoscope-assisted group compared with those in the traditional group (P < 0.05). No salivary fistulae occurred in either group, and all incisions in both groups healed primarily. No other complications such as Frey syndrome or persistent facial nerve palsy were documented in either group during the 3–6-month follow-up period.

The POSAS cosmetic outcomes included the following: the OSAS total score was 7.2 ± 0.7 in the endoscope-assisted group vs. 17.5 ± 2.5 in the traditional group (P < 0.01, Mann–Whitney U; lower scores indicate better scar quality); the corresponding PSAS scores were 7.5 ± 1.0 vs. 17.3 ± 3.4 (P < 0.01). During the 3–6-month follow-up period, complete tumor excision with confirmed benign pathology was achieved in all cases. Notably, no tumor recurrence or severe complications were observed in either group (Table 2). Figure 4 shows the typical front and side views of patients in the endoscope-assisted group and the traditional group 3 months postoperatively.

Table 2.

Comparison of the surgical parameters and complications between the two groups.

Items	Endoscope-assisted group (n = 48)	Traditional group (n = 48)	P-value
Operative time (mean ± SD, min)	154.7 ± 28.5	125 ± 16.7	0.014
Intraoperative blood loss (mean ± SD, mL)	22.4 ± 6.7	56.3 ± 5.4	<0.01
Postoperative drainage volume (mean ± SD, mL)	58.5 ± 12.3	118.7 ± 21.5	<0.01
Drainage duration (mean ± SD, days)	3.4 ± 0.5	6.1 ± 1.1	<0.01
Postoperative complications (cases (%))			0.013
Mild oral commissure deviation	4 (8.3)	20 (41.7)
Auricular numbness	8 (16.7)	24 (50.0)
Salivary fistula	0	0	NA
Frey syndrome	0	0	NA
Facial nerve palsy	0	0	NA
POSAS totals (mean ± SD)
OSAS (5–50), mean ± SD	7.2 ± 0.7	17.5 ± 2.5	<0.01
PSAS (6–50), mean ± SD	7.5 ± 1.0	17.3 ± 3.4	<0.01
Recurrence at 3–6-month follow-up	0	0

Data are presented as mean ± SD for continuous variables and n (%) for categorical variables. P-values for continuous variables were calculated via the independent-samples t-test (Welch’s t when variances were unequal); POSAS totals (OSAS/PSAS) were compared using the Mann–Whitney U test (lower scores = better outcomes); categorical outcomes were compared using χ² or Fisher’s exact test, as appropriate. Two-sided P < 0.05 was considered statistically significant.

NA: not applicable (no events occurred in either group); POSAS: Patient and Observer Scar Assessment Scale; OSAS: Observer Scar Assessment Scale; PSAS: Patient Scar Assessment Scale.

Figure 4.

Frontal and side views of the incision recovery of a patient with right parotid gland tumor resection 3 months after surgery. (a) Frontal view (smiling) and (b) lateral view of a representative patient from the traditional group, with arrows indicating the incision site. (c) Frontal view (smiling) with normal facial nerve function and (d) lateral view representing a patient in the endoscope-assisted group, with the arrow indicating the incision site.

Discussion

The primary goals of benign parotid tumor surgery are complete excision with facial nerve preservation and satisfactory cosmetic outcomes. Endoscope-assisted techniques can enhance visualization of the facial nerve trunk and branches and enable smaller, concealed incisions, improving cosmetic satisfaction. Rather than implying a universal surgeon preference, the current evidence highlights two complementary considerations: the patients’ demand for concealed, shorter scars ¹³ and technical feasibility and ergonomic features of the retroauricular hairline–cranial auricular groove approach for selected cases. ¹⁴ Accordingly, this approach may be adopted when cosmetic expectations and case anatomy align with these advantages.^15,16

Technical difficulty and nerve risk in large tumors

Large superficial-lobe tumors narrow the working space and may distort the branch anatomy, increasing the risk of traction or thermal injury. ¹⁷ This risk was mitigated by early trunk identification, nerve-oriented (distal-to-proximal) dissection, atraumatic counter-traction, and controlled energy use. ¹⁸ Despite the longer operative time in the endoscope-assisted group, the exposure was adequate without conversion, and minor sensory events were fewer in this group than in the traditional group (which used the modified Blair incision approach). ¹⁹

In our investigation, all patients in the endoscope-assisted group underwent successful procedures utilizing the retroauricular hairline–cranial auricular groove approach without necessitating a switch to open surgery. Complete excision of tumors with negative margins was achieved, as confirmed by postoperative pathology. Over the 3–6-month follow-up period, both cohorts exhibited comparable outcomes with no instances of tumor recurrence (0/48 vs. 0/48), underscoring the safety and viability of this method for managing larger benign parotid tumors. Notably, the operative duration was significantly longer in the endoscope-assisted group (154.7 ± 28.5 min) than in the traditional group (125 ± 16.7 min, P < 0.05). This discrepancy can be ascribed to various factors, including the time needed for flap elevation and cavity establishment; potential challenges in maintaining the orientation during tunnel creation and tumor localization; constraints associated with long-handled instruments in terms of angles and force transmission; the necessity to operate while relying on visual feedback from a screen, which complicates the identification of anatomical layers; and potential intraoperative hurdles such as repeated angle adjustments, frequent repositioning of the endoscope, field irrigation, and management of lens fogging. Furthermore, endoscope-assisted procedures lack direct assistance for retraction, grasping, and hemostasis achievement. In contrast, traditional open surgery provides extensive exposure through larger incisions, direct visualization during tumor and neurovascular dissection, and assistance and support for retraction and hemostasis. Despite longer operative times, the endoscope-assisted approach offers significant advantages in reducing surgical trauma, as indicated by the lower intraoperative blood loss (22.4 ± 6.7 vs. 56.3 ± 5.4 mL, P < 0.01), decreased postoperative drainage volume (58.5 ± 12.3 vs. 118.7 ± 21.5 mL, P < 0.01), and shorter drainage duration (3.4 ± 0.5 vs. 6.1 ± 1.1 days, P < 0.01). These results are consistent with the minimally invasive nature of this method, which promotes faster postoperative recovery. The utilization of endoscope-assisted technology enhances visualization, allowing surgeons to accurately identify crucial structures such as the facial nerve and blood vessels, leading to safer dissection—a critical aspect in achieving complete tumor resection while preserving facial nerve function.

Superficial parotid tumors are closely associated with the facial nerve trunk and its branches,^20–22 posing a significant challenge for facial nerve preservation during parotid surgery. Postoperative facial nerve monitoring was performed at early follow-up by assessing clinical symmetry (oral commissure deviation) and auricular sensation; future studies should adopt standardized grading (e.g. House–Brackmann) at predefined time points and electrophysiology when deficits persist. In conventional open parotidectomy, the complexity of identifying the facial nerve contributes to relatively high rates of postoperative nerve dysfunction,^23–25 ranging from 15% to 60%, with permanent injury occurring in 5%–10% of cases.^26,27 Our analysis of postoperative complications indicates that patients undergoing traditional surgery commonly experience auricular numbness and slight oral commissure deviation. For patients with tumors complicated by mild inflammation and adhesions, the endoscope-assisted approach offers notable benefits such as enhanced visualization of neural and vascular structures, improved identification capabilities, and reduced bleeding during surgery. These advantages facilitate precise anatomical dissection with minimal mechanical trauma, thereby lowering the risk of facial nerve damage. In contrast, traditional open surgery involves larger incisions leading to increased bleeding, particularly capillary oozing, and less precise neural identification compared with the magnified views provided by endoscopy.

A significantly lower incidence of facial nerve dysfunction was observed in the endoscope-assisted group (4/48, 8.3%) compared with that in the traditional group (20/48, 41.7%, P < 0.05). Additionally, the endoscope-assisted group demonstrated a notably lower rate of transient auricular numbness (8/48 vs. 24/48, 16.7% vs. 50.0%, P < 0.05). This difference may be attributed to our technique during flap elevation, involving the exposure and careful retraction of the great auricular nerve with the flap using endoscope-assisted retractors (refer to Methods—Intraoperative exposure and assistant roles), potentially inducing mild nerve stretching. Both groups experienced gradual symptom resolution, typically within 1 month. These results suggest that refining surgical techniques and minimizing traction could further reduce such complications. Importantly, all neurological dysfunctions observed were transient and completely resolved during the 3–6-month follow-up period, consistent with the existing literature. ²⁸

The consideration of postoperative aesthetic outcomes plays a pivotal role in determining the surgical approach for patients with parotid tumors.^29–31 The conventional modified Blair incision, situated prominently in the cervicofacial region, leads to visible scarring that can have a negative impact on the patients’ appearance and psychological well-being, a difference that is not only statistically significant but also clinically substantial. This improved esthetic outcome is attributed to the discreet placement of the retroauricular hairline–cranial auricular groove incision, which allows postoperative scars to be effectively concealed within the hairline or natural auricular contours or seamlessly blend with the cranial auricular groove. In contrast, the modified Blair incision in the conventional cohort results in conspicuous scarring in the exposed areas. The enhanced concealment of surgical incisions in our approach significantly enhances patient satisfaction, particularly among younger patients and those with heightened aesthetic expectations.

The benefits of endoscope-assisted superficial parotidectomy are highlighted by this study using a retroauricular hairline–cranial auricular groove incision for large parotid tumors. These advantages encompass the following: (a) discreet surgical openings, with the retroauricular incision concealed within the hairline and the cranial auricular groove incision obscured by the auricle; (b) improved visualization of the superior pole of parotid tumors facilitated by the cranial auricular groove incision design; (c) a larger flap area that enables enhanced endoscope-assisted visibility, reduced bleeding, and better identification of crucial neurovascular structures; (d) the capacity to tailor the incision length according to the precise preoperative tumor measurements obtained from advanced CT or MRI scans; (e) the auxiliary cranio-auricular sulcus incision and postauricular hairline incision are configured in a triangular arrangement, where their connecting line forms the hypotenuse. This design maximizes the surgical field width while minimizing the tunnel depth, thereby facilitating the resection of larger parotid tumors; and (f) decreased intraoperative blood loss, reduced postoperative drainage, shorter drainage duration, and expedited patient recovery. These advantages were substantiated by our data, particularly the notable discrepancies in intraoperative blood loss (22.4 ± 6.7 vs. 56.3 ± 5.4 mL, P < 0.01) and postoperative drainage volume (58.5 ± 12.3 vs. 118.7 ± 21.5 mL, P < 0.01). Despite the favorable outcomes observed in our cohort of 48 patients without significant postoperative complications, the utilization of retroauricular hairline–cranial auricular groove incision for endoscope-assisted superficial parotidectomy of parotid tumors ≥5 cm is still in the investigational phase, facing several constraints. These include the following: (a) the creation of a large flap area, which may predispose patients to specific postoperative complications; (b) prolonged operative duration compared with that in conventional open surgery (154.7 ± 28.5 vs. 125 ± 16.7 min, P < 0.05); (c) requirement for proficient endoscope-assisted surgical skills and experience, rendering the technique inappropriate for inexperienced surgeons; (d) possibility of conversion to open surgery, although not encountered in our study; and (e) the relatively small sample size in our study (n = 48), despite its comparative nature, underscores the need for larger studies with extended follow-up periods to confirm long-term efficacy.

The preliminary evidence from this study suggests that the endoscope-assisted approach via a retroauricular hairline–cranial auricular groove incision may represent a safe and effective alternative for excising large benign parotid tumors (≥5 cm), with potential advantages in esthetic outcomes compared with traditional surgery. Despite longer operative times, the endoscope-assisted approach was associated with lower intraoperative blood loss, lesser postoperative drainage, and shorter drainage duration. These findings highlight its potential value for patients prioritizing cosmetic outcomes.

Limitations

This was a retrospective, single-center study without a priori sample-size calculation; although all consecutive eligible cases were included (n = 96), precision for rare events is limited. The short follow-up period (3–6 months) restricts conclusions on long-term nerve recovery, sensation, or recurrence. A learning-curve effect may persist despite a fixed team and standardized steps. Finally, although POSAS provides objective patient and observer ratings, blinded external cosmetic adjudication was not performed. Future multicenter studies with longer follow-up are warranted to validate generalizability.

Conclusion

This study suggests that endoscope-assisted superficial parotidectomy via a retroauricular hairline–cranial auricular groove incision offers significant cosmetic benefits for large benign parotid tumors (≥5 cm) compared with the traditional modified Blair incision. Although operative time was longer in the endoscope-assisted group, it resulted in reduced blood loss, shorter drainage duration, and fewer sensory deficits. The technique showed promising outcomes in preserving facial nerve function and enhancing cosmetic results. However, further prospective studies with larger sample sizes and longer follow-up are needed to confirm these findings and assess long-term outcomes.

Supplemental Material

sj-pdf-1-imr-10.1177_03000605251396703 - Supplemental material for Endoscope-assisted superficial parotidectomy of large benign parotid tumor through a retroauricular hairline–cranial auricular groove incision approach: A retrospective study

Supplemental material, sj-pdf-1-imr-10.1177_03000605251396703 for Endoscope-assisted superficial parotidectomy of large benign parotid tumor through a retroauricular hairline–cranial auricular groove incision approach: A retrospective study by Longyu Zhang, Lijuan Guo and Sen Yang in Journal of International Medical Research