Usefulness of hybrid SPECT/CT for the 99mTc-HMPAO-labeled leukocyte scintigraphy in a case of cranial osteomyelitis

Abstract

Cranial osteomyelitis is a potentially fatal lesion. White blood cell scanning (WBC) with 99m Tc-hexamethylpropylene amine oxime (HMPAO) has proven highly sensitive and specific in the diagnosis and follow-up of patients with suspected osteomyelitis. In this report we show the usefulness of SPECT and transmission CT performed simultaneously using a hybrid imaging device for the functional anatomic mapping of soft tissue and cranial bone infections.99m Tc-HMPAO-labeled leukocytes scintigraphy was performed on an elderly diabetic man with an intracranial mass lesion and with suspected temporal bone infection. Planar scans were acquired 30 min, 4 h, and 24 h after injection. SPECT/CT was obtained 6 h after tracer injection, using a dual-head camera coupled with a low-power X-ray tube. The scintigraphic results were matched with the results of surgery and of clinical follow-up. The planar images alone were true-positives for abscess in this patient. SPECT/CT improves the accuracy of 99m Tc-HMPAO scintigraphy especially in discriminating between soft-tissue and bone involvement. In fact, SPECT/CT also showed temporal bone osteomyelitis. This result indicates that SPECT/CT performed using a hybrid device can improve imaging with 99m Tc-HMPAO-labeled leukocytes in patients with suspected osteomyelitis by providing accurate anatomic localization and precise definition of the extent of infection. Key-Words: SPECT/CT, brain abscess, 99m Tc-HMPAO-labeled leukocyte scintigraphy.Cranial osteomyelitis arises from complications of paranasal sinus infection, trauma, dental extractions, chronic mastoiditis, necrotizing otitis externa and various surgical procedures [1]. The diagnosis and localization of infection still represent a challenge for physicians. Because laboratory tests are relatively nonspecific, imaging is required to reach a correct diagnosis. Locating the site of infection is important for planning adequate treatment and evaluation the response to it [2].Various approaches have been developed to visualize inflammation and infection by nuclear medicine techniques. Tc-hexamethylpropylene amine oxime (HMPAO)-labeled leukocytes are often preferred for imaging inflammation, despite the relatively complex and time-consuming labeling procedure. These scintigraphic modalities are, however, limited by their low image resolution and lack of anatomic landmarks. The fusion of functional (i.e., SPECT) and morphologic (i.e., CT) images has significantly improved diagnostic accuracy as compared to that of using SPECT alone [3].We describe a case of brain abscess presenting as a high uptake lesion on labeled leukocyte.SPECT/CT had, in this case, a significantly higher incremental contributory value for WBC, contributing to the accurate identification of infection in a patient with suspected temporal osteomyelitis. Case ReportA 65 year old man with a one month history of pain in the right temporal region and fever (38°C), presented with weakness, disphagia and high blood pressure (200/95). His vital signs and his motor function we...

SPECT/CT in the Diagnosis of Skull Base Osteomyelitis

“…Potential complications include cranial neuropathy, cavernous sinus thrombosis, septicemia, and cerebral and meningeal involvement [4]. Typical skull base osteomyelitis involves the temporal bone and is usually a complication of malignant otitis externa in a diabetic/immunocompromised patient due to Pseudomonas aeruginosa.…”

Estudo de publicações em periódicos gerais de artigos sobre ortopedia e aparelho locomotor

“…[66][67][68] Chart 2 presents the number of articles located through the search strategy (Chart 1) and the number of articles selected by the authors for their relationship with the area of interest of orthopedics and study of the locomotor system. Table 1 presents the percentages of the localized articles relating to the topics addressed.…”

99mTc‐HMPAO‐leukocyte scintigraphy for diagnosis and therapy monitoring of skull base osteomyelitis

“…Bone scintigraphy (HMDP‐Tc‐99m) has the same limitations . Leukocyte scintigraphy (LS) is known to specifically detect bacterial infections, but very few data are available regarding LS in SBO . The aim of this study was to evaluate LS in SBO patients as a tool for the initial diagnosis and to confirm healing after antibiotherapy.…”