Health Dictionary
Reliable, easy-to-read patient information on common medical conditions — written in plain language, free of jargon, and grounded in current evidence. Browse the most frequent diagnoses, understand what they mean for everyday life, and learn which steps and questions help you have a focused conversation with your doctor.
Bell's palsy pathophysiology
Introduction
Overview
Overview
The exact pathophysiology of Bell’ palsy is not known. Bell’s palsy occurs due to failure to function in a normal manner of the facial nerve (VII cranial nerve). The malfunction of the facial nerve caused involuntary spasm in the facial muscles which called facial palsy. Bell’s palsy causes the lower motor neuron type paralysis. Although the exact etiology of Bell’s palsy is unknown, there is some evidences that implies there may be some relation between vasospasm, from any cause, along any facial nerve branch, with Bell’s palsy. There is no established association between genetic factors and Bell’s palsy. Hereditary components may play a role in familial recurrent Bell’s palsy. On microscopic histopathological analysis, thickened perineurium, infiltrates of inflammatory cells between nerve bundles and around blood vessels are characteristic findings of Bell’s palsy. It appears that the histology of the facial nerve in Bell’s palsy is similar to Herpes Zoster infection, suggestive of an infectious cause.
Pathophysiology
Pathophysiology
Pathogenesis
- The exact pathophysiology of Bell’ palsy is not known.[1]
- Bell’s palsy occurs due to failure to function in a normal manner of the facial nerve (VII cranial nerve).[2]
- The malfunction of the facial nerve caused involuntary spasm in the facial muscles which called facial palsy.[2]
- Bell’s palsy causes the lower motor neuron type paralysis.[3]
- Although the exact etiology of Bell’s palsy is unknown, there is some evidences that implies there may be some relation between vasospasm, from any cause, along any facial nerve branch, with Bell’s palsy.[4]
Genetics
Genetics
- There is no established association between genetic factors and Bell’s palsy.
- Hereditary components may play a role in familial recurrent Bell’s palsy.[5]
Associated Conditions
Associated Conditions
- Blepharospasm has been rarely seen in patients whit with Bell’s palsy.
- In most cases blepharospasm appeared within a month after the onset of Bell’s palsy.
2. Herpes zoster infection[7]
Microscopic Pathology
Microscopic Pathology
- On microscopic histopathological analysis, thickened perineurium, infiltrates of inflammatory cells between nerve bundles and around blood vessels are characteristic findings of Bell’s palsy.[8]
- It appears that the histology of the facial nerve in Bell’s palsy is similar to Herpes Zoster infection, suggestive of an infectious cause.[7] ==References==
- ↑ Somasundara D, Sullivan F (2017). “Management of Bell’s palsy”. Aust Prescr. 40 (3): 94–97. doi:10.18773/austprescr.2017.030. PMC 5478391. PMID 28798513.
- ↑ 2.0 2.1 Holland J, Bernstein J (2011). “Bell’s palsy”. BMJ Clin Evid. 2011. PMC 3275144. PMID 21375786.
- ↑ Newadkar UR, Chaudhari L, Khalekar YK (2016). “Facial Palsy, a Disorder Belonging to Influential Neurological Dynasty: Review of Literature”. N Am J Med Sci. 8 (7): 263–7. doi:10.4103/1947-2714.187130. PMC 4982354. PMID 27583233.
- ↑ Gussen R (1977). “Pathogenesis of Bell’s palsy. Retrograde epineurial edema and postedematous fibrous compression neuropathy of the facial nerve”. Ann Otol Rhinol Laryngol. 86 (4 Pt 1): 549–58. doi:10.1177/000348947708600416. PMID 889228.
- ↑ Qin D, Ouyang Z, Luo W (2009). “Familial recurrent Bell’s palsy”. Neurol India. 57 (6): 783–4. doi:10.4103/0028-3886.59478. PMID 20139511.
- ↑ Miwa H, Kondo T, Mizuno Y (2002). “Bell’s palsy-induced blepharospasm”. J Neurol. 249 (4): 452–4. doi:10.1007/s004150200038. PMID 11967652.
- ↑ 7.0 7.1 Morrow MJ (2000). “Bell’s Palsy and Herpes Zoster Oticus”. Curr Treat Options Neurol. 2 (5): 407–416. PMID 11096766.
- ↑ Liston SL, Kleid MS (1989). “Histopathology of Bell’s palsy”. Laryngoscope. 99 (1): 23–6. doi:10.1288/00005537-198901000-00006. PMID 2642582.
Editor-In-Chief: C. Michael Gibson, M.S., M.D. [1] ; Associate Editor(s)-in-Chief: Mohamadmostafa Jahansouz M.D.[2]