Frey's syndrome analysis with biosensor. A preliminary study

Frey's syndrome: A review of the physiology and possible role of neurotrophic factors

OBJECTIVES

Frey's syndrome (FS) describes the phenomenon of gustatory sweating and is a cause of significant social embarrassment for sufferers. It has been attributed to aberrant growth of parasympathetic salivatory fibers in the auriculotemporal nerve toward overlying sweat glands. However, the exact mechanism behind this growth is unknown. This review aims to expand and elucidate the theory of aberrant regeneration in FS.

METHODS

A review of the recent literature on nerve regeneration was conducted in order develop further insights into the etiology of both adult onset and pediatric FS.

RESULTS

Neurturin, a neurotrophic factor released by both salivary and sweat glands, was identified as a possible key player in the etiology of FS.

CONCLUSION

Further research into the role of neurturin could help to elucidate the pathogenic mechanisms underlying the condition and might reveal neurturin to be a potential target for pharmacological intervention.

LEVEL OF EVIDENCE

NA (Basic Science Review).

Effectiveness of platysma muscle flap in preventing Frey syndrome and depressive deformities after parotidectomy

BACKGROUND

Frey syndrome (FS) or depressive deformity (DD) occurring after parotidectomy significantly reduces a patient's quality of life. However, there seems to be no effective treatment strategy against these complications. In this study, we report our experience of using platysma muscle flap (PMF) to prevent the development of FS and DD after parotidectomy, and evaluate its effect subjectively and objectively.

METHODS

Superficial parotidectomy was performed for eight cases of parotid gland tumor, and a PMF was transferred to cover the site. The incidence of FS and DD were evaluated subjectively, using a questionnaire to the patients and board-certified reconstructive surgeons, and objectively, using Minor's starch-iodine test.

RESULTS

In seven patients, the defect could be completely covered with PMF, and none of them developed FS or obvious DD. However, in one patient, the defect could be only partially covered, and the patient developed complications in the exact site that the flap did not cover. Overall scores from the questionnaire were high in relation to both cosmetic and functional perspectives from most of the patients and all the surgeons. No patients had major postoperative complications requiring revision.

CONCLUSIONS

PMF can be useful to cover the defect and prevent complications after parotidectomy. PMF is relatively easy to perform with fewer complications; however, a complete coverage of the defect should be ensured to obtain optimal results.

Galvanic skin response test: a new quantitative diagnostic method for Frey syndrome

OBJECTIVE

Frey syndrome is one of the most common complications following parotid surgery. The current most common test for objectively diagnosing Frey syndrome is Minor starch-iodine test. This test might be insufficient because its results are not quantitative and therefore tests with quantitative results are investigated. The objective of this study was to investigate the efficiency of galvanic skin response (GSR) test, which measures changes in skin resistance, as a method with quantitative results for diagnosis of Frey syndrome.

METHODS

Thirty patients who underwent superficial parotidectomy were assessed postoperatively (mean, 24.7 ± 25.7 months; range, 6-109 months). Patients completed a symptomatic evaluation questionnaire and underwent Minor starch-iodine test and GSR.

RESULTS

Diagnostic validity of GSR test was found to be >2.91 following analysis. Sensitivity and specificity of this value were 100% and 55%, respectively, based on symptomatic assessment. Sensitivity and specificity were 87.5% and 57.1%, respectively, based on Minor starch-iodine test.

CONCLUSIONS

When compared to symptomatic evaluation of patients who underwent superficial parotidectomy, GSR test was shown to be 100% sensitive in diagnosing Frey syndrome and quantitative results of GSR test could determine severity of Frey syndrome.

Lactate in human sweat: a critical review of research to the present day

This review provides a critical overview of the literature published in the area of lactate in human sweat between 1934 and the present. The first section summarizes the relevant pieces of literature, the second evaluates the literature across a range of topics and the third presents potential applications for sweat lactate measurements. Key factors that may affect sweat lactate are discussed in detail in the second section of this review. Both acetylcholine and catecholamine hormonal signals can trigger sweating independently of one another; differences in sweat output and lactate concentrations are compared. The primary triggers for sweating, exercise and heat are also compared, with exercise-induced sweating being further examined with respect to the exercise intensity. This review examines the significant variations in sweat lactate between bodily sites as well the relationship to physiological parameters such as gender, age and physical fitness, along with the effect of climate adaptation on sweat lactate concentrations.

Lucja Frey--historical relevance and syndrome review

BACKGROUND

This article documents an objective review ofthe neuro-anatomical, diagnostic and clinical implications of the auriculotemporal syndrome (Frey's syndrome). The incidence of Frey's syndrome after parotidectomy as cited in the literature varies. It may also be a sequela to a variety of inflammatory, infective and traumatic aetiologies.

METHOD

An electronic search using the search engine Google, Medline and Pubmed was performed under 'Lucja Frey', 'Gustatory sweating', 'The auriculotemporal syndrome', 'Botulinum toxin'. Relevant papers were systematically reviewed from 1965 to present.

CONCLUSIONS

This disorder is important for ENT surgeons and allied specialties. We present the main surgical and cosmetic therapeutic strategies in the literature. We also discuss the fascinating life of Lucja Frey. As one of the first female academic neurologists in Europe, her career and life were tragically altered by the events of World War II.

Tissue Welding Forceps Usage in Superficial Parotidectomy: A Clinical Assessment

Tissue welding forceps (TWF) have been used effectively in a number of surgical procedures including blood vessel harvesting and tonsillectomy. Our objective was to assess the safety and efficacy of TWF usage in superficial parotidectomy. We performed a retrospective review of 25 patients between November 2002 and July 2006 who underwent superficial parotidectomy using TWF. The inpatient and outpatient records were reviewed for diagnosis, operative times, estimated blood loss, and postoperative facial paresis. Only one of the 25 patients (4%) who underwent superficial parotidectomy using TWF had transient postoperative facial weakness and no procedure had blood loss of greater than 150 cc. This initial evaluation suggests that use of TWF is safe in superficial parotidectomy and may help reduce the development of postoperative facial paresis.

Frey syndrome. A proposal for evaluating severity

We aimed to establish the incidence of Frey's syndrome in patients that have been submitted to partial and total parotidectomy at a cancer-treating hospital in Mexico City and to propose a grading system to determine its severity. The incidence of Frey's syndrome in 77 patients (25 male and 52 female) under oncological follow-up due to parotid tumors was subjectively evaluated through clinical findings and objectively diagnosed through Minor's test. The positive hyperhydrotic areas were recorded and measured on transparent acetates. Numeric values were assigned according to clinical perception of symptomatology by the patients (0 for no perception and 1 for clinical recognition), extent of the affected area (1 if less than 2 cm; 2 if between 2.1 and 4 cm, and 3 if more than 4 cm), intensity and smell of sweat (3 if it was excessive or of unpleasant odor). Results were expressed as mild (if less than 4 points) or severe grades (if 4 or more points). Frey syndrome was objectively diagnosed in 28 patients (36%), although only 17 (22%) recognized to have clinical manifestations of this condition. There were 22 women (79%) and six men (21%). Of these, seventeen (61%) had been subjected to partial and eleven (39%) to total parotidectomy. Adjuvant radiotherapy had been employed in nine cases (32%). The cutaneous affected area in the whole group ranged from 0.7 to 29.8 cm(2) (mean 8.9 cm(2)), with a mean affected surface of 8.7+/-10.8 cm(2) for women and 9.0+/-8.8 cm(2) for men ( p > 0.05). Twelve cases were classified as mild and sixteen as severe. No significant differences were found between patients treated with partial vs. total parotidectomy or between patients treated with or without adjuvant radiotherapy. The incidence of Frey's syndrome in Mexican patients seems to be similar to those reported in other countries; however, the extent of hyperhydrosis is lower when compared to some European studies. Our proposal for evaluating this condition may be a helpful tool in assessing the incidence and severity among the diverse populations and it may be a useful tool to define more precisely the indications for treatment and to evaluate the available therapeutic methods according to the severity of the condition.

Botulinum toxin A in the treatment of patients with Frey syndrome

BACKGROUND

This was a prospective study of the treatment of Frey syndrome, also known as gustatory sweating, with botulinum toxin A.

METHODS

Thirteen patients with a mean involved skin area of 53 (range 36-80) cm2, as assessed with the Minor starch-iodine test, were treated with 0.1 ml toxin (75 units/ml) injected intracutaneously into every 4 cm2 of involved skin. The mean total dose was 100 (range 67.5-150) units. Treatment results were assessed every 3 months with the Minor test. The Frey Questionnaire Card (FQC) was used for subjective assessment. The mean follow-up after primary treatment was 20 (range 9-24) months. Treatment was repeated if the symptoms recurred.

RESULTS

After 3 months 11 of the 13 patients showed a decrease of gustatory sweating of more than 90 per cent. All but one patient with a follow-up of 2 years suffered recurrent gustatory sweating. The mean recurrence-free period after primary treatment was 11 months and that after secondary treatment was 15 months. FQC score and objective assessment correlated well. Treatments were well tolerated, although two patients developed a temporary perioral muscle paresis.

CONCLUSION

Botulinum toxin A produces good results in the treatment of Frey syndrome. Repeated treatment improves on the results of primary treatment.

Botulinum toxin type A for Frey's syndrome: a preliminary prospective study

Fourteen patients with severe Frey's syndrome (occurring after conservative parotidectomy) managed with intracutaneous injection of botulinum toxin type A were prospectively evaluated. Results were analyzed for effectiveness, complications, and adverse effects. Complications were not encountered. The only adverse effect noted was a temporary and slight partial paresis of the upper lip of 3 months' duration in 2 patients. Permanent paresis was not encountered. Frey's syndrome was always controlled within 2 days following the intracutaneous injection of botulinum toxin A. Frey's syndrome recurrence was not encountered with a follow-up duration that varied from 3 to 9 months (mean follow-up 7 months). This preliminary report confirmed that in patients who have Frey's syndrome after conservative parotidectomy, the intracutaneous injection of botulinum toxin is a valuable treatment option that should be further investigated.

Oral contraceptives alter circadian rhythm parameters of cortisol, melatonin, blood pressure, heart rate, skin blood flow, transepidermal water loss, and skin amino acids of healthy young women

Sixteen healthy women users and nonusers of oral contraceptives (OC) volunteered to document a set of circadian rhythms. Nine were taking OC providing ethynyl estradiol (0.03-0.05 mg/24h, 21 days/month) combined with DL- or L-norgestrel or norethisterone. There was no group difference (p > 0.05) in median age (22 years), weight (57 kg), and height (162) cm). Data were obtained at fixed hours, 5 times/24h, during a 48-h span, in November. (Day activity from approximately 08:00 to approximately 23:00 h and night rest). Environmental conditions were controlled, using air-conditioned rooms of constant temperature (26 degrees +/- 0.5) and relative humidity 45% +/- 1. Both cosinor and ANOVA were used for statistical analyses. All circadian rhythms were validated with one exception: that of salivary melatonin was not detected in OC users. The 24h mean (M) exhibited group differences for certain variables: M was greater in OC than non-OC users for systolic blood pressure (p < 0.0001), heart rate (p < 0.01), skin blood flow (p < 0.04), and transepidermal water loss (p < 0.02). M was lower in OC than non-OC users in salivary cortisol (p < 0.04) and skin amino acids (p < 0.003). No group difference was detected in any other documented rhythms: diastolic blood pressure, grip strength of both hands, oral temperature, self-rated fatigue, and the skin variables of urea, lactate, triglycerides, and acid phosphatase activity.