Incidental detection of superior sternal cleft on Technetium-99m methylene diphosphonate bone scan
A 45-years old male patient, who was a recently diagnosed case of moderately differentiated adenocarcinoma of prostate with Gleason's score of 3 + 4 = 7, was referred for Tc-99m MDP bone scan to rule out skeletal metastases. He complained of upper backache for 2 months and had a history of trauma to the left lower leg 1 week prior to performing the bone scan. The serum prostate specific antigen level was >100ng/ml. On clinical examination, there was a midline bony defect in the region of the manubrium sterni with no apparent bulge or paradoxical respiratory movements.\nA whole body planar Tc-99m MDP bone scan and single-photon emission computed tomography-computed tomography (SPECT-CT) of the thoracic region was performed 3 h after intravenous injection of 20 mCi of Tc-99m MDP on a dual head gamma camera (Infinia: single slice SPECT-CT; GE, USA). The study was performed with a urinary catheter in situ.\nThe planar images of the bone scan revealed focal MDP uptake in the D4 vertebra [ (red arrow)], focal uptake in the mid shaft of the left tibia [ (blue arrow)] and a U-shaped photopenia in the region of the sternum [ (black arrow)]. Corresponding SPECT-CT images of the thorax revealed localization of the focal tracer uptake in the sclerotic metastasis in the body of the D4 vertebra [ (red arrows)]. The U-shaped photopenia in the sternum corresponded to a bony cleft involving the manubrium and upper half of the sternum [ (blue arrow)].\nThe Tc-99m MDP bone scan thus helped in diagnosing a congenital superior sternal cleft, metastasis in the body of the D4 vertebra and post-traumatic changes in the mid shaft of the left tibia.