Frey Syndrome—An Underreported Complication to Closed Treatment of Mandibular Condyle Fracture? Case Report and Literature Review

Innsbruck-style Retromandibular Anterior Trans-parotid Approach for Condylar Fractures: A Retrospective Review of 39 Fractures

The retromandibular anterior trans-parotid (RAT) approach and a triangular-positioned double mini-plate osteosynthesis (TDO) technique have been reported from Innsbruck Medical University. This minimally invasive technique involves direct visualization of the condyle and is associated with lower incidence of facial palsy.

Methods

A retrospective review was performed on the RAT approach and TDO technique conducted by a surgeon and team at two hospitals in Tokyo during a period of 3 years and 10 months.

Results

This technique was performed on 35 patients with 39 condylar fractures. Sixty-nine percent of cases were due to accidental fall, 17% to traffic accidents, and 9% to sports. Furthermore, 92% cases were condylar base fractures. Nighty-seven percent of cases achieved good occlusion. The mean maximum mouth opening was 49 ± 1.3 mm. Postoperatively, facial palsy developed in three patients (7.7%), and two of them developed Frey syndrome at approximately 2.5 years postoperatively (5.1%). All patients completely recovered within 3 months postoperatively. One case each of salivary fistula, visible scar, and condylar resorption was found (2.6%). No case of massive bleeding during surgery, hematoma, or TMJ pain after surgery was found.

Conclusion

This technique could achieve good occlusion with low incidence of complications and could contribute to early social reintegration among patients.

Auriculotemporal Frey syndrome not associated with surgery or diabetes: systematic review

Patients who undergo salivary gland, neck, or facelift surgery or suffer from diabetes mellitus often develop Frey syndrome (also known as auriculotemporal syndrome or gustatory sweating). Frey syndrome has been occasionally reported to occur in subjects without history of surgery or diabetes but this variant of Frey syndrome has not been systematically investigated. We searched for original articles of Frey syndrome unrelated to surgery or diabetes without date and language restriction. Article selection and data extraction were performed in duplicate. Our systematic review included 76 reports describing 121 individual cases (67 males and 54 females) of Frey syndrome not associated with surgery or diabetes. The age at onset of symptoms was ≤ 18 years in 113 (93%) cases. The time to diagnosis was 12 months or more in 55 (45%) cases. On the other hand, an allergy evaluation was performed in half of the cases. A possible cause for Frey syndrome was detected in 85 (70%) cases, most frequently history of forceps birth (N = 63; 52%). The majority of the remaining 22 cases occurred after a blunt face trauma, following an auriculotemporal nerve neuritis or in association with a neurocutaneous syndrome. The cause underlying Frey syndrome was unknown in 36 cases.   Conclusion: Frey syndrome not associated with surgery or diabetes almost exclusively affects subjects in pediatric age and is uncommon and underrecognized. Most cases occur after forceps birth. There is a need to expand awareness of this pseudo-allergic reaction among pediatricians and allergists. What is Known: • Pre-auricular reddening, sweating, and warmth in response to mastication or a salivary stimulus characterize Frey syndrome. • It usually occurs after salivary gland surgery and in diabetes. What is New: • In children, Frey syndrome is rare, and most cases occur after a forceps-assisted birth. • In childhood, this condition is often erroneously attributed to food allergy.

Frey's Syndrome: A Review of Aetiology and Treatment

First described by Polish Neurologist Łucja Frey in 1923, Frey's syndrome (FS), or auriculotemporal syndrome, is a rare condition characterised by gustatory sweating, typically encountered as sequelae following invasive head and neck surgery. The pathophysiology of FS can be described by aberrant reinnervation of postganglionic parasympathetic neurons to the surrounding denervated sweat glands and cutaneous blood vessels. Multiple invasive procedures have been associated with FS ranging from salivary gland surgery to burn reconstruction and thoracoscopic sympathectomies. Rarely, FS can be secondary to trauma or non-surgical aetiologies, including diabetes and infection. Physical symptoms vary based on the severity and surface area affected by FS and range from mild symptoms to severe psychosocial morbidity for patients. Surgeons operating in the head and neck, including otolaryngologists, maxillofacial surgeons, and plastic surgeons, should be aware of this potential complication and be up to date with diagnosis and treatment strategies for FS. This review article summarises the literature relating to FS focusing on its aetiologies, symptomatology, prevention, and available treatments, aiming to provide an up-to-date review of this condition for surgeons operating in the head and neck region. Although various treatment options have been suggested, these are often limited to topical agents that require life-long administration for symptom control. Further research is recommended to identify the optimal treatment for this condition and the role of surgery as a treatment for severe or refractory cases.

Confronting the Challenges of Anatomy Education in a Competency-Based Medical Curriculum During Normal and Unprecedented Times (COVID-19 Pandemic): Pedagogical Framework Development and Implementation

BACKGROUND

Anatomy is considered to be one of the keystones of undergraduate medical education. However, recently, there has been drastic reduction, both in gross anatomy teaching hours and its context. Additionally, a decrease in the number of trained anatomists and an increase in the costs associated with procuring human cadavers have been noted, causing a diminution of cadaveric dissections in anatomy education.

OBJECTIVE

To address these challenges, there is an ardent need for a pedagogical framework such that anatomy education can be disseminated through active learning principles, within a fixed time frame, using a small team of anatomists and a small number of cadaveric specimens (for live on-site sessions) as well as collaborative learning principles. The latter is particularly important when anatomy education is delivered through distance learning, as is the case currently during the COVID-19 pandemic.

METHODS

Here, we have blueprinted a pedagogical framework blending the instructional design models of Gagne's 9 events of instruction with Peyton's 4-step approach. The framework's applicability was validated through the delivery of anatomical concepts, using an exemplar from the structure-function course Head and Neck during the normal and COVID-19-mandated lockdown periods, employing the archetype of Frey syndrome. Preliminary evaluation of the framework was pursued using student feedback and end-of-course feedback responses. The efficiency of the framework in knowledge transfer was also appraised.

RESULTS

The blueprinted instructional plan designed to implement the pedagogical framework was successfully executed in the dissemination of anatomy education, employing a limited number of cadaveric specimens (during normal times) and a social media application (SMA)-integrated "interactome" strategy (during the COVID-19 lockdown). Students' response to the framework was positive. However, reluctance was expressed by a majority of the faculty in adopting the framework for anatomy education. To address this aspect, a strategy has been designed using Mento's 12-step change management model. The long-term benefits for any medical school to adopt the blended pedagogical framework have also been explicated by applying Bourdieu's Theory of Practice. Additionally, through the design of an SMA interactome model, the framework's applicability to the delivery of anatomy education and content during the ongoing COVID-19 pandemic was realized.

CONCLUSIONS

In conclusion, the study effectively tackles some of the contemporary key challenges associated with the delivery of anatomy content in medical education during normal and unprecedented times.

Temporoparietal frey syndrome: An uncommon variant of a common syndrome

OBJECTIVES/HYPOTHESIS

To describe a previously unreported variant of Frey syndrome. Gustatory sweating is a common complication of parotidectomy and typically directly overlies the surgical site or parotid bed. In some instances, the sweating may occur beyond the parotid bed or involve tissue that was undisturbed during the procedure.

STUDY DESIGN

Retrospective case series.

METHODS

All cases of temporoparietal Frey syndrome in a single surgeon's experience were reviewed.

RESULTS

Seven patients were found to have temporoparietal Frey syndrome. Three patients had concomitant first bite syndrome. Three patients had some form of reconstruction at time of surgery. The mean time to onset of symptoms was 11.5 months, with a range of 7 to 21 months. Four patients did not require any treatment for their symptoms, but two patients required intradermal Botox injections for symptomatic relief.

DISCUSSION

This study describes a previously unreported variant of Frey syndrome with symptoms occurring distal to the parotid gland. This likely develops either by regeneration of severed postganglionic fibers into sympathetic targets distally along the course of the auriculotemporal nerve or by regeneration into fibers of the sympathetic plexus traveling along the superficial temporal artery.

LEVEL OF EVIDENCE

Laryngoscope, 129:2071-2075, 2019.

Thermography as a quantitative imaging method for assessing postoperative inflammation

OBJECTIVE

To assess differences in skin temperature between the operated and control side of the face after mandibular third molar surgery using thermography.

METHODS

127 patients had 1 mandibular third molar removed. Before the surgery, standardized thermograms were taken of both sides of the patient's face using a Flir ThermaCam™ E320 (Precisions Teknik AB, Halmstad, Sweden). The imaging procedure was repeated 2 days and 7 days after surgery. A region of interest including the third molar region was marked on each image. The mean temperature within each region of interest was calculated. The difference between sides and over time were assessed using paired t-tests.

RESULTS

No significant difference was found between the operated side and the control side either before or 7 days after surgery (p > 0.3). The temperature of the operated side (mean: 32.39 °C, range: 28.9-35.3 °C) was higher than that of the control side (mean: 32.06 °C, range: 28.5-35.0 °C) 2 days after surgery [0.33 °C, 95% confidence interval (CI): 0.22-0.44 °C, p < 0.001]. No significant difference was found between the pre-operative and the 7-day post-operative temperature (p > 0.1). After 2 days, the operated side was not significantly different from the temperature pre-operatively (p = 0.12), whereas the control side had a lower temperature (0.57 °C, 95% CI: 0.29-0.86 °C, p < 0.001).

CONCLUSIONS

Thermography seems useful for quantitative assessment of inflammation between the intervention side and the control side after surgical removal of mandibular third molars. However, thermography cannot be used to assess absolute temperature changes due to normal variations in skin temperature over time.