Category: Musculoskeletal Imaging, Region: Head-Bones, Plane: Other
A 31 year-old Malay gentleman, with no underlying co-morbidities except for being an active smoker, initially presented to us in the year 2008 with complaints of pain and swelling at the right mandibular region for a duration of more than a year. The pain and swelling was over the right mandibular region was associated with pain and dysphagia. The patient had given history of seeking treatment from a private clinic but to no avail. An examination of the patient revealed a localized swelling at the right mandibular region that was tender on palpation and associated with trismus and pericoronitis of the right third molar tooth. A working diagnosis of a submasseteric abscess secondary to right third molar pericoronitis was made and a differential diagnosis of a mandibular tumour was also suspected. A Total White Blood Cell Count (TWBC) was done and it was reported as 8.0. He was admitted and given a course of intravenous Cefobid 1g twice daily (BD) and Metronidazole 500mg thrice daily (TDS). A CT scan was then done to further investigate the patient. The outcome of the investigation showed a rim enhancing lesion with air fluid level at the right mandibular region with erosion of the underlying bone (Figure 1). The swelling reduced as the oral antibiotic therapy was continued, however the pain persisted. The patient was then discharged with the medication of tablet Cefuroxime 500mg BD and tablet Metronidazole 500mg TDS upon discharge for 2 weeks and on follow up, the right mandibular condyle was not palpable with a notable deviation of the mouth to the right side. A radiograph was done and it showed erosion of the ramus of right mandible. A clinical diagnosis of osteomyelitis of right mandible was made and a CT scan was performed to review the disease progress. The scans was done within 2 months and it showed bony destruction of the right mandibular condyle and ramus with an aggressive right masticator space soft tissue lesion. The right submandibular lymph node was not enlarged during this time frame (Figure 2). An explorative surgery was then conducted. Intra-operatively, a soft tissue mass was seen distal to the right 3rd molar – this was curretted and sent for a histopathological examination. The report returned as non-specific showing mild to moderate infiltration of chronic inflammatory cells. The TWBC at this time was 7.2. The patient was continued on the prescribed oral antibiotics and requested to return for a follow-up, which he defaulted. In January 2010, the patient presented to the dental department with a complaint of pain and swelling at the right submandibular region associated with an upper respiratory tract infection. The pain at the right submandibular region was attributed to reactive lymphadenitis. He was prescribed with tablet Erythromycin Ethyl Succinate 400mg BD as outpatient. However the right submandibular swelling persisted and he was subsequently diagnosed with reactive lymphadenitis likely secondary to underlying osteomyelitis of the right mandible and given a course of antibiotics (Capsule Cloxacillin 500mg QID and tablet metronidazole 400mg TDS for a week). In Feb 2010, the patient had developed a dental issue that required a tooth extraction of the 2nd right lower molar and the dentist who noticed the right mandible swelling also subjected the patient to a soft tissue biopsy. The result of the biopsy was reported as acute on chronic granulomatous inflammation. A culture and sensitivity swab was taken during the procedure. The report showed no growth of any organism. TWBC was 7.6 with the Erythrocyte Sedimentation Rate (ESR) of 12mm/hr (not raised). An x-ray done later showed that the right mandible was nearly totally resorbed. This prompted the dental team to subsequently refer the patient to the plastic surgery team in 2011 for a suggested reconstruction of the right mandible. Upon referral and discussion with the patient about the potential complications, the patient put a hold on the surgical decision for nearly 2 years. During this time, clinically the underlying infective process appeared to have resolved, however in March 2013, he again presented to the casualty with a right submandibular swelling and pain. He was referred to the dental team. Upon examination and imaging, a decision to conduct an aspiration cytology was made. Pus was aspirated from the buccal mucosa and sent for a culture and sensitivity (results were unknown). Diagnosis of a submandibular abscess secondary to impacted wisdom tooth and was given a course of antibiotics for 5 days as outpatient. Swelling resolved, however, he presented again with complaint of right facial deformity (face sunken) two weeks later. He was again subjected to a CT scan examination for the right side of the mandible in April 2013. It showed multiple areas of bone resorption involving the ramus and body of right mandible likely secondary to previous granulomatous infection with an enlarged and avidly enhancing right submandibular lymph node (Figure 3). No soft tissue tumour was seen on CT. ESR and C-Reactive Protein (CRP) at this time was within normal limits. Patient was counseled for a reconstruction of right mandible with a non-vascularized bone graft and excision of the right submandibular lymph node. This was done in 2014 (6 years after his initial presentation). The result of the biopsy of the right submandibular lymph node showed Castleman lymphadenopathy which was a hyaline-vascular variation. He was well post-surgery and discharged. He however developed right mandibular pain and malocclusion in early 2015. An orthopantomogram was done and showed resorption of the reconstructed mandible (Figure 4). Another CT was done showed resorption of the bone graft with no evidence of soft tissue tumour (Figure 5). He was counseled for removal of implant with vascularized bone flap which was planned for 6.9.2016 however it was postponed due to the patient being unwell. The patient was subsequently lost to follow up. Unfortunately, through-out the hospital follow-up, no infective screening was done for this patient.