Diagnosis And Treatment Of Herpes Virus Infection Following Laser Subepithelial Keratomileusis

Infectious keratitis is one of the most serious complications after lasersubepithelial keratomileusis(LASEK). Herpes virus infection followingLASEK often leads to serious damage of vision, the main causes of virusinfection including: stimulation of corneal by surgery and the recurrence oflatent herpes virus irradiated by excimer laser; long-term topical administrationof steroids eye drops, or the interaction of all above factors. Once the herpetickeratitis appears, early and correct diagnosis and management are critical forrescuing the visual acuity. Viral culture has been recognized as the goldstandard for diagnosing herpes virus infection. But it has limitation, it’s notsuitable for rapid diagnosis. Multiplex PCR was used to amplify several targetgenetic segments and was regarded as a sensitive method to detect virus.Treatment consist of topical and systemic antiviral therapy.Objective:Viral culture and multiplex PCR was used to detect herpes virus. Thesensitivity and accuracy of Multiplex PCR was compared to that of viral culture.The etiology and the effect of combination of antiviral therapy on herpetickeratitis after LASEK were investigated.Methods:A retrospective study was carried out on9patients (15eyes) whodeveloped viral keratitis at one to three months postoperative from2008to2010in our cohort. The diagnosis was evaluated primarily according to theclinical findings and then the multiplex PCR and viral culture were used tofurther determine the diagnosis and identify the categories of viruses. The tears,corneal or conjunctival swabs were used as specimens. Furthermore, the effect of combining antiviral therapy on herpetic keratitis was testified.Results:Herpes simplex virus type1(HSV-1) was identified by viral culture in6eyes (6/15,40%). Thirteen of15eyes were positive by multiplex PCR, amongthem HSV-1was identified in12eyes while varicella-zoster virus (VZV) wasidentified in one eye. The results indicate that multiplex PCR was moresensitive than viral culture. The cornea clarity was restored in8patients（13eyes）after antiviral therapy. Only one patient（2eyes）remained Haze (grade Iand II respectively).Conclusions:(1) Our study indicates that HSV-1is the most common reason of viralinfection after LASEK. VZV should be considered when skin eruptiondeveloped.(2) Because the Bowman’s layer and anterior stroma were ablatedby excimer laser after LASEK, the typical dendritic ulcer or geographic ulcer inthe cornea were not observed in our study. The clinical observations of thesepatients showed a mild irritation with atypical single or diffused lesions, easilyto develop Haze. So it is difficult to make diagnosis on the basis of the atypicalclinical findings.(3) Multiplex PCR is an accurate and rapid method todetermine the diagnosis and identify the categories of various viruses using aminute amount of specimen.(4)The combination of therapy is effective toherpetic keratitis after LASEK and could be shorten the duration of active viraldisease.