Bone scintigraphy has been used for diagnosis of osteomyelitis of the jaw, but there is no index to objectively evaluate uptake value and uptake volume.
The development of software for bone SPECT fixed-quantity analysis has enabled various SUV analyses, such as PET imaging. GI-BONE（AZE Co., Ltd., Japan）is novel analysis software for SPECT bone scintigraphy that may be useful for evaluating treatment for osteomyelitis of the jaw. We report a case of monitoring osteomyelitis of the jaw, in which images of the healing process were monitored using GI-BONE.
A 71-year-old man was referred to our department presented with swelling and sharp pain in the lower right mandible. Because of bone metastasis due to prostate cancer, zoledronic acid（4mg） had been administrated intravenously 24 times every four weeks for about two years from January 2015. He had spontaneous pain of the mandible and we found two swollen fistulas in the right gingiva; we drained the pus and administered amoxicillin. After one week, swelling of the gingiva had improved and we performed imaging SPECT bone scintigraphy. After eight weeks, we diagnosed it as ARONJ Stage 2. We conducted SPECT bone scintigraphy to monitor the healing process of the osteomyelitis after five months and again after eight months.
Then, we analyzed SPECT data using GI-BONE software. The monitoring data showed that SUVmax and MBV（metabolic bone volume） were significantly improved. Eighteen months from the first diagnosis, CT imaging revealed separation of the sequestrum, so we removed it with minor surgery, and ARONJ was healed.