Auto-Fluorescence guided surgical approach of Medication-Related Osteonecrosis of the Jaw (MRONJ): a case report.

Abstract

Event Abstract Back to Event Auto-Fluorescence guided surgical approach of Medication-Related Osteonecrosis of the Jaw (MRONJ): a case report. Chiara Manzoli1*, Ilaria Giovannacci1, Marco Meleti1, Luigi Corcione1, Domenico Corradi1 and Paolo Vescovi1 1 University of Parma, Department of Medicine and Surgery, Italy Aim. Medication- Related Osteonecrosis of the Jaw (MRONJ) is an adverse side effect of several drug therapies, including bisphosphonates (BPs) and other antiresorptive and antiangiogenic drugs such as Denosumab, Bevacizumab, Sunitinib and Aflibercept, commonly used for the treatment of resorptive bone diseases (for e.g. multiple myeloma, bone metastases, primary and secondary osteoporosis and Paget’s disease of bone). The therapeutic management of the MRONJ is a subject of discussion due to low evidence in literature about the results after a long time from treatment (in particular regarding surgical procedures). The main purposes of each treatment are the pain reduction, the infection control and the slowing of the progression of the disease; the main objective is the elimination of the MRONJ with complete healing. Precise identification of necrotic bone margins during osteonecrosis removal is a major difficulty for surgeons being mainly based on subjective parameters such as bleeding, texture and colour of the bone. Ristow suggested in 2014 that vital bone when irradiated with a blu-violet wavelenght could be highlighted on the basis of its strong Auto-Fluorescence (AF) whereas necrotic bone lost such an AF appearing very dark. The aim of this work is to present a case describing a new surgical approach for MRONJ using AF in highlighting surgical margins. Histopathological evaluation of fluorescent and non-fluorescent bone was also performed in order to establish a more accurate correlation between fluorescence and bone vitality. Materials and Methods. A 77-year- old Caucasian male with a bone exposure localized to the right hemimandible with irregularity of the cortex at the lingual level of the retromolar trigon and the mylohyoid line arrived for diagnosis; the patient reported mandibular pain and anesthesia of the lower lip. He stopped smoking 5 years ago and never had any alcohol or drug problems. He had no allergies and he is negative for all HIV, HCV and HBV markers. His medical history including the removal of a prostate cancer and he was treated with chemotherapy and 24 zoledronic acid infusions (since 2012). With the direct visual intra-operative fluorescence examination (VELscopeTM -LED Medical Diagnostics Inc., Barnaby, Canada) the lesion appeared as an extensive hypo-fluorescent sequestrum. The diagnostic hypothesis was MRONJ at the Ib stage (SICMF SIPMO Staging System),. The surgical treatment consisted in a vaporization with erbium- doped yttrium aluminium garnet laser (Er: YAG- Fidelis Plus®, Fotona - Slovenia; Parameters: 300 mJ , 30 Hz, fluence 60 J/cm2) under local anesthesia, until obtaining an extremely hyper- fluorescent bone surface. The inferior alveolar nerve was isolated in order to carry out osteoplasty up to the detection of hyper-fluorescent tissue. No postoperative complications, as well as no swelling and/or pain reported by the patient, have been observed; he was followed up after 21 days, after 1 month and after 36 months. Results. The bone that appeared hypo-fluorescent with AF examination resulted as necrotic tissue according to the histopathological evaluation, instead the hyper-fluorescent bone resulted as vital tissue. The diagnosis is of MRONJ at the III stage (SICMF SIMPO Staging System), according to the clinical appearance and the microscopic examination. No postoperative complications, as well as no swelling and/or pain reported by the patient, have been observed; he was followed up after 21 days, after 1 month and after 36 months. Discussion. Taking into account the effectiveness and reproducibility of AF in highlighting surgical margins of necrotic bone, the approach described here will probably allow to achieve excellent outcomes in surgical treatment of MRONJ. Moreover, Er:YAG laser may represent a useful option in terms of reduction of invasiveness: in fact its wavelength allows the vaporization of necrotic bone with good control of bone removal because of its affinity for water and hydroxyapatite allowing a superficial action. This technique is related to a good comfort during and after surgery for the patient with a reduction of postsurgical morbidity (with a reduction/elimination of pain and edema) and a better and faster healing