Adult-onset congenital cholesteatoma in the hypotympanum initially presenting as Bell's palsy: A case report.

INTRODUCTION: Cholesteatoma is a rare disease characterized by the accumulation of keratinized squamous epithelial cells in the middle ear or mastoid cavity. Vertigo and facial palsy, which are rare complications, may indicate erosion into the semicircular canals or the fallopian canal. PATIENT CONCERNS: A 40-year-old woman presented to our clinic with progressive right-sided hearing loss over 5 years (primary concern). Approximately 10 years ago, the patient had developed acute right-sided facial weakness with no additional symptoms. A neurologist at another hospital had diagnosed her condition as Bell's palsy and treated it accordingly. DIAGNOSIS: Adult-onset congenital cholesteatoma in the hypotympanum. INTERVENTION: Combined endoscopic and microscopic removal of the cholesteatoma. OUTCOMES: Physical examination revealed slight improvement in right-sided peripheral facial palsy. LESSON: Routine eardrum examination is recommended for patients presenting with isolated peripheral facial palsy. If necessary, a patient should be referred to an otologist for further evaluation and treatment.

Facial Function in Bell Palsy in a Cohort of Children Randomized to Prednisolone or Placebo 12 Months After Diagnosis.

BACKGROUND: Information on the medium-term recovery of children with Bell palsy or acute idiopathic lower motor neuron facial paralysis is limited. METHODS: We followed up children aged 6 months to <18 years with Bell palsy for 12 months after completion of a randomized trial on the use of prednisolone. We assessed facial function using the clinician-administered House-Brackmann scale and the modified parent-administered House-Brackmann scale. RESULTS: One hundred eighty-seven children were randomized to prednisolone (n = 93) or placebo (n = 94). At six months, the proportion of patients who had recovered facial function based on the clinician-administered House-Brackmann scale was 98% (n = 78 of 80) in the prednisolone group and 93% (n = 76 of 82) in the placebo group. The proportion of patients who had recovered facial function based on the modified parent-administered House-Brackmann scale was 94% (n = 75 of 80) vs 89% (n = 72 of 81) at six months (OR 1.88; 95% CI 0.60, 5.86) and 96% (n = 75 of 78) vs 92% (n = 73 of 79) at 12 months (OR 3.12; 95% CI 0.61, 15.98). CONCLUSIONS: Although the vast majority had complete recovery of facial function at six months, there were some children without full recovery of facial function at 12 months, regardless of prednisolone use.

Bell's palsy: a case report of unusual presentation in a patient with rhino-orbital cerebral mucormycosis.

BACKGROUND: Mucormycosis is a fungal infection caused by the Mucorales order of fungi. This fungus is commonly found in soil and can cause disease in immunocompromised patients. On the other hand, Bell's palsy is an idiopathic condition that results in the sudden onset of unilateral facial muscle weakness, affecting the facial nerve. CASE PRESENTATION: A 51-year-old Persian housewife with a history of poorly controlled diabetes mellitus presented with a splitting headache that had been ongoing for 1 week and an inability to close her left eye or make facial expressions on the left side of her face. The patient's vital signs were normal, but physical examination revealed a yellow-grey scar on the left side of her hard palate and Bell's palsy on the left side. A neurological examination showed that she could move both eyes but could not close her left eye, move up her left eyebrow, or smile. Further investigations were performed, including laboratory tests, radiologic imaging, and functional endoscopic sinus surgery. The patient underwent three rounds of debridement for bony erosion in the medial and posterior walls of the left maxillary sinus and the hard palate. Pathological examination confirmed mucormycosis infection in the hard palate and mucosa. CONCLUSION: Fungal infection must be considered a potential diagnosis for immunocompromised adults who exhibit symptoms of Bell's palsy.

Complete Hemifacial Paralysis Post-facelift: Making Sense of a Plastic Surgeon's Worst Nightmare.

BACKGROUND: Postrhytidectomy hemifacial paralysis is a frightening clinical condition affecting the proximal facial nerve and most often associated with Bell's palsy. Associated symptoms are common and include auditory, salivary, vestibular, and gustatory complaints. OBJECTIVES: The aim of the study was to provide increased awareness of postrhytidectomy hemifacial paralysis secondary to Bell's palsy in the plastic surgery community. METHODS: Following a roundtable discussion with the senior author's (J.C.G.) plastic surgery colleagues located all over the world, 8 surgeons reported having had firsthand experience with hemifacial paralysis in patients following facelift. Descriptions of their cases, including preoperative, intraoperative, and postoperative courses were collected and reported. RESULTS: A total of 10 cases of postrhytidectomy hemifacial paralysis were analyzed based on results of a clinical questionnaire. Eight of the 10 cases involved all facial nerve branches, with 2 cases sparing the marginal mandibular branch. The vast majority of cases were referred to a neurologist and steroids initiated. Two patients were returned to the operating room for exploration. Associated symptoms reported included pain in the ear, hearing loss, ocular symptoms such as tearing or dryness, vestibular symptoms such as vertigo, changes in taste, and in 1 patient an electric-shock type sensation to the face. CONCLUSIONS: Hemifacial paralysis associated with Bell's palsy following rhytidectomy is a rare but known clinical entity that should be included in the preoperative informed consent process before facelift. Current management trends are neurology referral and steroid initiation.

Comparison of oral versus intravenous steroid in the management of Bell's palsy: a systematic review and meta-analysis of randomized clinical trials.

BACKGROUND: Bell's palsy is a condition affecting cranial nerve VII that results in acute peripheral unilateral facial weakness or paralysis of unclear etiology. Corticosteroids are the primary therapy choice, because they improve outcomes. According to a recent study, prednisolone effectively treats Bell's palsy in the short and long term. This study aimed to assess the effectiveness and safety of Single-Dose Intravenous Methylprednisolone to Oral Prednisolone in treating Bell's palsy patients. METHODS: PRISMA statement guidelines were used to design and conduct this systemic review. MEDLINE, Cochrane Library, and EMBASE databases were used in our search. We conducted the database search in November 2022. RESULTS: Thirty-three publications were reviewed as a result of the literature review. Three studies were included in the meta-analysis after applying our criteria. 317 Bell's palsy patients were included in our study. Regarding complete recovery to grade 1 in 1 month, IV methylprednisolone was higher than oral prednisolone; (log OR = 0.52, 95% CI [0.08, 0.97], P = 0.022). However, at 3 months, the two groups had no significant difference. Patients with grade 4 Bell's palsy were more likely to fully recover to grade 1 in 1 month with IV methylprednisolone than with oral prednisolone (log OR = 0.73, 95% CI [0.19, 1.26], P = 0.008), but not for patients with grade 3 or grade 2 Bell's palsy. CONCLUSION: This study shows evidence that patients with Bell's palsy can fully recover to grade 1 in 1 month when IV methylprednisolone is used instead of oral prednisolone. At 3 months, however, there was no discernible difference between the two treatments. Within 3 days of the onset of symptoms, IV methylprednisolone treatment can be started, which may help patients recover fully to grade 1 in 1 month. However, administering IV methylprednisolone may not always have long-term advantages compared to oral prednisolone.

Variations in the treatment of acute peripheral facial paralysis. A nationwide survey.

BACKGROUND: Acute peripheral facial paralysis may be diagnosed and treated by different specialists. OBJECTIVE: The aim of this study was to explore the variability in the treatment of Bell's palsy (BP) and Ramsay Hunt Syndrome (RHS) among different medical specialties. METHODS: An anonymous nationwide online survey was distributed among the Spanish Societies of Otorhinolaryngology (ORL), Neurology (NRL) and Family and Community Medicine (GP). RESULTS: 1039 responses were obtained. 98% agreed on using corticosteroids, ORL using higher doses than NRL and GP. Among all, only 13% prescribed antivirals in BP routinely, while 31% prescribed them occasionally. The percentage of specialists not using antivirals for RHS was 5% of ORL, 11% of NRL, and 23% of GP (GP vs. NRL p = 0.001; GP vs. ORL p < 0.0001; NRL vs. ORL p = 0,002). 99% recommended eye care. Exercises as chewing gum or blowing balloons were prescribed by 45% of the participants with statistically significant differences among the three specialties (GP vs. NRL p = 0.021; GP vs. ORL p < 0.0001; NRL vs. ORL p = 0.002). CONCLUSION: There is general agreement in the use of corticosteroids and recommending eye care as part of the treatment of acute peripheral facial paralysis. Yet, there are discrepancies in corticosteroids dosage, use of antivirals and recommendation of facial exercises among specialties.

Bell's Palsy and COVID-19: Insights from a Population-Based Analysis.

Background: Coronavirus disease 2019 (COVID-19) has been linked to Bell's palsy and facial paralysis. Studies have also shown increased risk of Bell's palsy in unvaccinated COVID-19 patients. Objective: To compare the relationship between Bell's palsy and COVID-19 infection and vaccination. Design: This is a retrospective longitudinal study. Methods: The COVID-19 research network was used to identify patients with facial palsy presenting to 70 health care organizations in the United States. The incidence of Bell's palsy was measured within an 8-week window after COVID-19 test or vaccination event in identified patients. Results: Incidence of facial palsy diagnosis (0.99%) was higher than the background rate within 2 months of COVID-19 infection. When compared with their negative counterparts, patients with COVID-19 infection had significantly higher risk of Bell's palsy (risk ratio [RR] = 1.77, p < 0.01) and facial weakness (RR = 2.28, p < 0.01). Risk ratio was also amplified when evaluating Bell's palsy (RR = 12.57, p < 0.01) and facial palsy (RR = 44.43; p < 0.01) in COVID-19-infected patients against patients who received COVID-19 vaccination. Conclusion: In our patient population, there is a higher risk of developing facial palsy within 2 months of COVID-19 infection versus vaccination. Vaccinated patients are not at higher risk of developing facial palsy.

The Rate of Occult Lesion Diagnosis in a Large Bell's Palsy Cohort.

OBJECTIVES: We characterize occult lesion diagnosis rates after initial Bell's palsy diagnoses. METHODS: A de-identified database of all facial palsy patients who presented to an extensive health care system across 22 years was created using Epic SlicerDicer. Among patients with Bell's palsy diagnoses, we extracted demographic and any subsequent occult lesion diagnosis data across various clinical sites. Descriptive and multivariable regression analyses comparing patients with occult lesion diagnoses made at different time points were included. RESULTS: Among the total 3912 facial palsy patients, 2240 had Bell's palsy diagnoses, of which 217 (9.7%) had subsequent lesion diagnoses at a median (IQR) of 12.3 (4.2, 23.8) months, consisting of cranial nerve neoplasms (62.2%), parotid gland neoplasms (34.1%), and cholesteatomas (3.7%). Although a large proportion of total lesions were diagnosed within the first 3 months (19.8%), 69.5% were diagnosed after 6 months. There were no demographic differences among patients diagnosed with different lesion types, but Asian patients were more likely to be diagnosed with occult lesions after 12 months after Bell's palsy diagnosis compared with white patients (odds ratio = 6.2, p = 0.001). CONCLUSIONS: In one of the largest Bell's palsy cohorts to date, we identified a 9.7% occult lesion diagnosis rate at a median of 12.3 months after Bell's palsy diagnosis. These data underscore the importance of timely workup for occult lesions in cases of facial palsy with no signs of recovery after 3-4 months. LEVEL OF EVIDENCE: 4 Laryngoscope, 134:911-918, 2024.

Bell Palsy: Facts and Current Research Perspectives.

Bell palsy is a non-progressive neurological condition characterized by the acute onset of ipsilateral seventh cranial nerve paralysis. People who suffer from this type of facial paralysis develop a droop on one side of their face, or sometimes both. This condition is distinguished by a sudden onset of facial paralysis accompanied by clinical features such as mild fever, postauricular pain, dysgeusia, hyperacusis, facial changes, and drooling or dry eyes. Epidemiological evidence suggests that 15 to 23 people per 100,000 are affected each year, with a recurrence rate of 12%. It could be caused by ischaemic compression of the seventh cranial nerve, which could be caused by viral inflammation. Pregnant women, people with diabetes, and people with respiratory infections are more likely to have facial paralysis than the general population. Immune, viral, and ischemic pathways are all thought to play a role in the development of Bell paralysis, but the exact cause is unknown. However, there is evidence that Bell's hereditary proclivity to cause paralysis is a public health issue that has a greater impact on patients and their families. Delay or untreated Bell paralysis may contribute to an increased risk of facial impairment, as well as a negative impact on the patient's quality of life. For management, antiviral agents such as acyclovir and valacyclovir, and steroid treatment are recommended. Thus, early diagnosis accompanied by treatment of the uncertain etiology of the disorder is crucial. This paper reviews mechanistic approaches, and emerging medical perspectives on recent developments that encounter Bell palsy disorder.

Electroacupuncture with intermittent wave stimulation as rehabilitation approach for chronic Bell's palsy: a randomized controlled trial.

PURPOSE: To evaluate the effectiveness and safety of electroacupuncture (EA) using intermittent wave stimulation in enhancing facial symmetry and nerve function in chronic Bell's palsy patients. METHODS: A 6-week assessor-blinded, randomized trial followed by an 18-week observational period was conducted. Sixty individuals with chronic Bell's palsy, showing no signs of recovery after 12 months, were equally divided to receive either 18 sessions of EA using intermittent wave stimulation or Transcutaneous Electrical Stimulation (TES), administered thrice weekly over 6 weeks. The primary outcome measure was the change in the total facial nerve index (TFNI) score from baseline to Week 6, with secondary outcomes including TFNI scores at Weeks 12 and 24, as well as the change in Sunnybrook Facial Grading System (SFG) score from baseline to Week 6, and SFG scores at Weeks 12 and 24. RESULTS: The EA group showed a significant improvement, with a mean total facial nerve index score increase of 24.35 (4.77) by Week 6 compared with 14.21 (5.12) in the Transcutaneous Electrical Stimulation group (P<.001). This superiority persisted during the 24-week follow-up. While no significant difference was observed in the Sunnybrook Facial Grading System score change from baseline to Week 6, variations were noted at Weeks 12 and 24. No major adverse effects were reported. CONCLUSION: EA with intermittent wave stimulation notably enhanced facial symmetry in chronic Bell's palsy patients over Transcutaneous Electrical Stimulation by Week 6, maintaining this edge throughout the follow-up.

The Significance of Bell's Palsy That Presents as Monocranial Versus Polycranial Neuropathy: A Case Series and Systematic Literature Review.

PURPOSE: To investigate the effect of Bell's palsy (BP) presenting as polycranial neuropathy (PCN) compared with BP caused by isolated facial nerve (CNVII). METHODS: We carried out a retrospective cohort study of the medical records of all consecutive patients who were diagnosed with BP at a single tertiary referral center between 2010 and 2017. Included were patients 18 years or older who were clinically diagnosed with BP and completed 7 days of systemic steroidal treatment and at least 6 months of follow-up. The patients were divided into two groups according to whether the BP derived from a monocranial neuropathy or a PCN. Demographics and BP severity and outcome were compared between these groups. A systematic literature review using Medline via "PubMed," "Embase," and "Web of Science" was conducted. RESULTS: In total, 321 patients with BP were enrolled. The median (interquartile range) age at presentation was 44 (33-60) years. Sex distribution showed male predominance of 57.6% (n = 185) versus 42.4% (n = 136), and 21.2% (n = 68) had PCN. The most concomitantly affected cranial nerve (CN) was the trigeminal (CNV; n = 32, 47%), followed by the glossopharyngeal nerve (CNIX; n = 14, 21%) and the audiovestibular nerve (CNVIII; n = 10, 15%). Age, House-Brackmann score on presentation, and diabetes mellitus (DM) were independent predictors for PCN etiology ( p = 0.001, p = 0.034, and p < 0.001, respectively). Each increase in 1 year of age was associated with additional odds ratio (95% confidence interval) of 0.97 (0.95-0.99) for PCN. The odds ratio (95% confidence interval) associated with DM was 8.19 (4.02-16.70). Our systematic literature review identified 1,440 patients with the PCN type of BP. The most commonly affected CN was the trigeminus (25-48%), followed by the glossopharyngeal and audiovestibular nerves (2-19% and 0-43%, respectively). CONCLUSION: The severity of facial weakness on initial presentation among PCN patients was significantly higher compared with the monocranial neuropathy-type BP patients. The authors believe that the significant association and prevalence rate ratio between DM and PCN warrant that a patient presenting with PCN undergo screening for DM.

Association of plasma atherogenic index with the severity and prognosis of Bell's palsy.

BACKGROUND: The plasma atherogenic index (AIP) is used as an indicator of cardiovascular risk. Abnormal lipid levels have been shown to potentially contribute to facial nerve inflammation observed in Bell's palsy. This study sought to investigate the association of AIP with the severity and prognosis of Bell's palsy. MATERIAL AND METHODS: AIP is calculated using the equation Log (triglyceride [mg/dL]/high-density lipoprotein cholesterol [mg/dL]). The study was conducted prospectively on 79 patients diagnosed with Bell's palsy. The House-Brackmann (H-B) grade was used to determine the severity of Bell's palsy. RESULTS: In total, 79 patients [45 (57%) male and 34 (43% female] with Bell's palsy were included to the study. The mean (SD) age was 54.1 (16.5). In multivariable analyses prediction of unrecovered patients, the Odds Ratio (OR) and Confidence Intervals for NLR was 1.322 (1.021-1.797), p = .032, for PLR was 1.100(1.068-1.250), p = .043, for total cholesterol was 1.038 (1.001-1.076), p = .039, for AIP was 4.250 (2.239-8.226), p = .005. The highest area under curve (0.74) was observed for AIP to predict unrecovered Bell's palsy with 71.4% sensitivity and 62.7% specificity. CONCLUSIONS AND SIGNIFICANCES: AIP is associated with advanced-stage facial paralysis at the time of Bell's palsy diagnosis and can be used as a poor prognostic indicator.

Examining the relationship between COVID-19 and Bell's palsy: Experience of a single tertiary care center.

BACKGROUND: While the etiology of Bell's palsy (BP) is largely unknown, current evidence shows it may occur secondary to the immune response following a viral infection. Recently, BP has been reported as a clinical manifestation of coronavirus disease (COVID-19). OBJECTIVES: To investigate an association between COVID-19 infection and BP. Additionally, to evaluate the need for COVID-19 testing in patients who present with BP. METHODS: Hospital records of patients who presented to a single tertiary care center with BP in 2020 and 2021 were reviewed for presenting symptoms, demographics, COVID-19 infection and vaccination status. RESULTS: There was no statistically significant difference between patients with BP who had a positive or negative COVID test in terms of sex, BMI, age, race, smoking history or alcohol use. All 7 patients with BP and a positive COVID test were unvaccinated. Of the total cohort of 94 patients, 82 % were unvaccinated at the time of the study. None of the 17 patients who were vaccinated had a positive COVID test. A history of BP showed no statistical significance (10.3 % vs 14.3 %, p-value 0.73). CONCLUSION: We discovered a limited cohort of patients who underwent COVID-19 testing at the time of presentation for BP. Though there have been recent studies suggesting a COVID-19 and BP, we were unable to clearly identify a relationship between COVID-19 and BP. Interestingly, all patients with facial paralysis and COVID-19 were unvaccinated. To further study this relationship, we recommend consideration of a COVID-19 test for any patient that presents with facial paralysis.

Persisting facial nerve palsy or trigeminal neuralgia - red flags for perineural spread of head and neck cutaneous squamous cell carcinoma (HNcSCC).

BACKGROUND: Perineural spread (PNS) of head and neck cutaneous squamous cell carcinoma (HNcSCC) is a unique diagnostic challenge, presenting with insidious trigeminal (CN V) or facial nerve (CN VII) neuropathies without clinically discernible primary masses. These patients are often sub-optimally investigated and misdiagnosed as Bell's palsy or trigeminal neuralgia. This case series highlights the red flags in history and pitfalls that lead to delays to diagnosis and treatment. METHODS: A retrospective case series of 19 consecutive patients with complete clinical histories with HNcSCC PNS without an obvious cutaneous primary lesion at time of presentation to a quaternary head and neck centre in Australia were identified and included for analysis. RESULTS: Fifteen had CN VII PNS, 17 had CN V PNS, and 13 had both. The overall median symptom-to-diagnosis time was 12-months (IQR-15 months). Eight patients had CN VII PNS and described progressive segmental facial nerve palsy with a median symptom-to-diagnosis time of 9-months (IQR-11.75 months). Eleven patients had primary CN V PNS and described well localized parathesia, formication or neuralgia with a median symptom-to-diagnosis time of 19-months (IQR 27.5 months). CONCLUSION: PNS is often mistaken for benign cranial nerve dysfunction with delays in diagnosis worsening prognosis. Red flags such as progressive CN VII palsy or persistent CN V paraesthesia, numbness, formication or pain, particularly in the presence of immuno-compromise and/or a history of facial actinopathy should raise suspicion for PNS. Gadolinium-enhanced MR Neurography should be obtained expediently in patients with persistent/progressive CN V/CN VII palsies in patients with red flags, with low threshold for referral to a Head and Neck Surgeon.

[Facial palsy: diagnostic traps]. / Paralysie faciale : pièges diagnostiques.

Peripheral facial palsy is a common, often idiopathic and self-limiting mononeuropathy. However, secondary facial palsies require specific management: they are most often of infectious, vascular or dysimmune causes. The presence of red flags in the history, clinical examination or medical follow-up should alert clinicians. Because of the high incidence of Lyme disease in our region, this etiology deserves special attention. The management is based on general measures (eye protection, rehabilitation) and corticosteroid therapy; antivirals may provide additional benefit.

La paralysie faciale périphérique (PFP) est une mononeuropathie fréquente, souvent idiopathique et autorésolutive. Cependant, les paralysies faciales secondaires nécessitent une prise en charge spécifique : elles sont le plus souvent de causes infectieuses, vasculaires ou dysimmunes. La présence de drapeaux rouges à l'anamnèse, à l'examen clinique ou lors du suivi médical doivent alerter les cliniciens. En raison de l'incidence élevée de la borréliose dans nos régions, cette étiologie mérite une attention particulière. La prise en charge repose sur des mesures générales (protection oculaire, rééducation) et sur la corticothérapie ; l'ajout d'antiviraux pourrait apporter un bénéfice supplémentaire.

[Bell's palsy: a broad differential diagnosisHouse-Brackmann-schaal]. / Bellse parese: een brede differentiaaldiagnose.

Peripheral facial palsy is a common clinical symptom and is most often caused by Bell's palsy. The pathogenesis is largely unknown, but inflammation of the facial nerve, possibly after a viral infection, may play a role. Bell's palsy has a monophasic course with usually - but not always - a good recovery. Even though Bell's palsy exhibits clear clinical features, in clinical practice diagnosis and choice of treatment remain difficult and other causes of an isolated facial palsy may easily be overlooked. Score INormale functie van aangezicht op alle gebieden Score II Globaal: lichte zwakte bij nauwkeurig onderzoek; mogelijk zeer lichte synkinesieën. In rust: normale symmetrie en tonus. Motoriek: - Voorhoofd: matig tot goede functie. - Oog: volledige sluiting met minimale inspanning. - Mond: lichte asymmetrie. Score IIIGlobaal: duidelijke, maar niet-ontsierend verschil tussen twee zijdes; opvallende, maar geen ernstige synkinesieën, contracturen of hemifacialisspasmen. In rust: normale symmetrie en tonus. Motoriek: - Voorhoofd: lichte tot matige beweging. - Oog: volledige sluiting met inspanning. - Mond: lichte zwakte met maximale inspanning. Score IV Globaal: duidelijke zwakte of ontsierende asymmetrie. In rust: normale symmetrie en tonus. Motoriek: - Voorhoofd: geen. - Oog: onvolledige sluiting. - Mond: asymmetrie met maximale inspanning. Score V Globaal: nauwelijks waarneembare beweging. In rust: asymmetrie. Motoriek: - Voorhoofd: geen. - Oog: onvolledige sluiting. - Mond: lichte beweging. Score VI Geen beweging.

COVID-19 associated Bell's Palsy and lumbosacral neurolymphomatosis in a patient with B-cell lymphoma-Case Report.

This is a case of acute onset unilateral Bell's Palsy during COVID-19 illness, coinciding with development of progressive leg pain, weakness, and sensation change. The patient was ultimately found to have a large B-cell lymphoma mass invading the sciatic nerve, lumbosacral plexus and the spinal canal with compression of cauda equina consistent with neurolymphomatosis. Although COVID-19 infection has been associated with Bell's palsy, Bell's palsy has also been reported with lymphoid malignancy. We review current literature on the association of Bell's palsy with COVID-19 infection and lymphoid malignancy, as well as review the diagnostic challenges of neurolymphomatosis. Providers should be aware of the possible association of Bell's palsy as harbinger of lymphoid malignancy.

Bell's palsy was associated with TRPV2 downregulation of Schwann cell by cold stress.

OBJECTIVE: Epidemiological and clinical studies have shown that sharp changes in the ambient temperature are associated with the occurrence and development of Bell's palsy. However, the specific pathogenesis of peripheral facial paralysis remains nebulous. This study investigated the effect of cold stress on transient receptor potential cation channel subfamily V member 2 (TRPV2) secretion by Schwann cells and its role in Bell's palsy. MATERIALS AND METHODS: Schwann cell morphology was observed using transmission electron microscopy (TEM). Cell proliferation, apoptosis and cell cycle were analysed using CCK8 and flow cytometry. ELISA, Reverse transcription-quantitative PCR, western blotting and immunocytochemical fluorescence staining were used to detect the effects of cold stress on TRPV2, neural cell adhesion molecule (NCAM) and nerve growth factor (NGF) expression in Schwann cells. RESULTS: Cold stress resulted in a widening of the intercellular space, and the particles on the membrane showed different degrees of loss. Cold stress may cause Schwann cells to enter a cold dormant state. ELISA, RT-qPCR, western blotting and immunocytochemical fluorescences staining indicated that cold stress inhibited the expression of TRPV2, NCAM, and NGF. CONCLUSIONS: Drastic temperature difference between cold and heat can downregulate TRPV2 and the secretome of Schwann cells. The imbalance of Schwann cell homeostasis under such stress may contribute to nerve signalling dysfunction leading to the development of facial paralysis.