ARTICLE
The use of hyfrecation in the treatment of verrucae, a case study. Mr. Robert Sullivan. BSc (Hons), PgDip. Pod. Surg., PgCert. L.A., PgDip.Pom’s. SARSM, M.Inst.ChP and Ms. Deirdre O’Flynn BSc. (Podiatry) M.Inst.ChP. An old but good definition of hyfrecation is; a form of high frequency electrosurgery where a low powered electrical impulses are delivered to the surface of the skin via a blunt or sharp electrode.(Sebben 1988). The application of the electrode has differing effect on the skin, either elec‐ trodessication, where the tissue is coagulated and desiccated without burning or electrofulguration where the skin is burnt causing carbonisation of the tissue. Current literature shows that hyfrecation itself does not interfere with nerve conduction due to its high frequency (Plant 2002, Gupta 2003, Fernando et al 2004), pain is caused by the heat generated in the tissue. When hyfrecation is used on verrucae the area must be well anesthetised using a suitable local anaesthetic and appropriate infiltration. It is the author’s experience that the lesion is best pared down prior to the use of the hyfrecator. Both techniques of electrodessication and electrofulguration are used to gain adequate access and depth in the removal of the verrucae. Hyfrecation is contraindicated in patients with a pacemaker as there is the potential for interference for the frequency of the pulse generated (Bridenstine 1998). The Case A 37 year old male presented to clinic with an interesting story in relation to his verraucal presentation. The patient had sought advice from at least three other clinicians and engaged several different treatments including cryotherapy, the application of salicylates and sliver nitrate all to no avail. By this time the client was frustrated and in an amount of pain in both his foot and his wallet. The gentleman is employed as a computer technician in the financial services industry and enjoys some light swimming reading and travelling. The medical history of the patient revealed a heart condition for which he was medicated and also taking a maintenance dose of aspirin 75mg. A review of his previous treatments shows a number of issues in relation to patient compliance as attendance was sporadic with the patient presenting only when he had pain. This gives reason for the condition continuing for the past five years. At this stage all the patient wants is for the condition to resolve as soon as possible. The treatments available were discussed with the patient; these included Cantheron Plus®, Spiralarin®, liquid cryogen and surgery. The client decided that he did not have the patience for topical applications and requested hyfrecation under a local anaesthetic. A full vascular and venous assessment was performed using Doppler® Fig. 1. All pulses were present with no areas of concern Figure 1. Doppler examination Picture from file The implications of surgery were discussed as well as complications which could arise. The patient was told of the importance of compliance to the pre and post op requirements and an information pack given. A letter was sent to the patient’s doctor advising of the condition and the proposed remedy, along with an instruction to withdraw the aspirin five days prior to surgery. The doctor replied and the appointment was made. Figure 2 shows the patients presentation of recalcitrant verrucae prior to surgery.
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Figure 2 HPV prior to removal. Picture from file. The patient history was checked and confirmation sought that the aspirin had been withdrawn 5 days post op. Any allergies information was verified and a consent from for the anaesthesia and operation was signed by the clinician and the patient. The patient was prepared for surgery (a 5ml vial was opened of which 2.5mls was drawn up) and the administration of a post tibial block using a solution of 2% lidocaine was administered. The patient was then left for 20 minutes for the anaesthetics to take full effect. Figure 3 below shows the anatomy of the nerve and associated structures. The posterior tibial nerve (arrow, yellow structure) is seen coursing beneath the flexor retinaculum (arrowheads) in this illustration viewed from the medial side. The posterior tibial artery lies next to the nerve. The posteromedial ankle tendons (white arrows) lie along the anterior aspect of the posterior tibial neurovascular bundle. A good identity maker for the correct location of the nerve is to find the pulse of the PTA and rest a finger on it, aim the needle to just miss the finger for injection of the anaesthetic solution. The anaesthetic should be placed around the nerve not in it. Figure 3. Showing anatomy for anaesthetic injection. (Googlemedicalimages) Within this type of surgery two techniques are used to treat the verrucae 1 fulguration and 2 desiccation. Figure 4 below show the two forms of electrosurgery/hyfrecation Figure 4. (A) Electrodesiccation with an active electrode tip touching the skin and showing penetration of planned tissue damage. (B) Fulguration with sparking from electrode to tissue. Treatment area is more superficial than in desiccation. After 20 minutes the patient was taken into the minor procedures room and the procedure commences after the foot had been checked for anaesthesia. Any excess calus over the verrucae is reduced using a 15 blade or appropriate. The outer border of the verrucae is delineated using the hyfrecator and the surface layer of skin is desiccated using the electrode. After desiccation the outer layer of skin has a white charred appearance as in Figure 5.