Peripheral facial palsy after topical photodynamic therapy for facial actinic keratoses
Authors: Franco Gemigniani, Domingo Bodet, Beatriz González-Llavona, Vicente García-Patos
Journal: Journal of the American Academy of Dermatology (2014)

To the Editor: A 64-year-old man presented with multiple actinic keratoses (AK) in sun-exposed skin. Previous treatments included cryotherapy and a single treatment with topical photodynamic therapy (PDT) to frontal AK leading to partial response. We performed a second treatment with topical methyl-aminolevulinate (MAL) PDT to AK on the left side of the forehead, temple, cheek, and jaw. We applied a total amount of 2 g of MAL cream over a treatment field of about 120 cm2, which was kept under occlusive dressing for 3 hours. After this, we irradiated the area with a dose of 37 J/cm2 of red light (wavelength, 630 nm) and this was well tolerated. One week after MAL-PDT the patient developed a complete paralysis of the left hemifacial muscles. He did not have a history of recent fever, pain, hyperacusis, numbness, or loss of sensation around the affected side ear. The ear, nose, and throat examination revealed normal findings and no herpetic vesicles were found. He presented normal results for brain magnetic resonance imaging and computed tomography scans. Other secondary causes of peripheral facial palsy (PFP) such as otitis, mastoiditis, Lyme disease, Guillain-Barre syndrome, trauma, and tumors were ruled out, and a working diagnosis of an idiopathic left PFP was established (Fig 1). We treated the patient with systemic corticosteroids for 2 weeks without response. Sixteen months after disease onset, no clinical improvement was observed. Topical PDT is a nonsurgical treatment approved for certain superficial nonmelanoma skin cancers and AK. PDT is generally well tolerated, and the most frequently reported adverse effect is local pain.1Ibbotson S.H. Adverse effects of topical photodynamic therapy.Photodermatol Photoimmunol Photomed. 2011; 27: 116-130Crossref PubMed Scopus (73) Google Scholar, 2Miguélez A. Martín-Santiago A. Bauzá A. Gilaberte Y. Urticaria-like reaction secondary to photodynamic therapy in 2 pediatric patients.Actas Dermosifiliogr. 2013; 104: 727-729Crossref PubMed Scopus (4) Google Scholar In our case, we observed a correlation between topical MAL-PDT and the development of an ipsilateral PFP after 1 week, which suggests a causal association. Currently, reactivation of herpes simplex virus at the geniculate ganglion is thought to be the most common cause of idiopathic PFP (Bell palsy).3Ellis L.Z. Prado R. Francis S. Lee L.A. Bell palsy following a minor dermatologic procedure.Arch Dermatol. 2012; 148: 268-269Crossref PubMed Scopus (2) Google Scholar In our case the stress, pain, or infection produced by the PDT could have triggered the viral reactivation. PFP caused by herpes zoster oticus (Ramsay Hunt syndrome) should also be considered in the absence of a vesicle eruption, ie, zoster sine herpete.4Gilden D. Cohrs R.J. Mahalingam R. Nagel M.A. Neurological disease produced by varicella zoster virus reactivation without rash.Curr Top Microbiol Immunol. 2010; 342: 243-253Crossref PubMed Google Scholar However, in our case we did not perform any viral tests to demonstrate the association between viral infection and PFP. An alternative explanation is the development of paralysis of the superficial facial nerve branches of the left-side face as a side effect of MAL-PDT. Recently, 2 cases of iatrogenic PFP after intracranial PDT for treatment of malignant gliomas have been published.5Varma A.K. Muller P.J. Cranial neuropathies after intracranial Photofrin-photodynamic therapy for malignant supratentorial gliomas–a report on 3 cases.Surg Neurol. 2008; 70: 190-193Abstract Full Text Full Text PDF PubMed Scopus (5) Google Scholar The authors suggest that energy could pass through thin bones overlying the photosensitized facial nerve in the intratemporal portion and induce nerve damage. Our case is of particular interest, as PFP has not been previously described in association with PDT. We present an undocumented case of a 64-year-old man who developed left PFP 1 week after topical PDT. Although uncommon, his symptoms may be considered as a possible complication of PDT, considering the close relation among the treated zone, the superficial localization of facial nerve branches, and the short elapsed time.