Loss of Mickey Mouse Ears' Sign in Progressive Supranuclear Palsy.

ABSTRACT: Progressive supranuclear palsy (PSP) is the most prevalent form of degenerative atypical parkinsonism. Clinical manifestations of PSP commonly encompass deficits in vertical gaze, postural stability, akinesia, and cognitive impairment. The characteristic metabolic pattern observed in PSP through FDG PET displays hypometabolism in the midbrain, striatum, thalamus, and frontal lobe. However, visual interpretation of midbrain hypometabolism poses challenges. In this report, we aim to elucidate a novel observation termed the "loss of Mickey Mouse ears' sign," which signifies midbrain hypometabolism as detected through visual assessment of FDG PET images.

18 F-FDG PET/CT in Synovial Anaplastic Large Cell Lymphoma.

ABSTRACT: Anaplastic large cell lymphoma is an uncommon and aggressive form of peripheral T-cell lymphoma. Synovial anaplastic large cell lymphoma is very rare. We present PET/CT findings in a patient with synovial anaplastic large cell lymphoma. Intense FDG accumulation was found in irregular synovial thickening of the right knee. Biopsy of the synovium was performed and revealed anaplastic large cell lymphoma. This case demonstrates that anaplastic large cell lymphoma should be included as one of the differential diagnoses of FDG-avid synovial lesions.

Rare Occurrence of Scapulothoracic and Ischiogluteal Bursitis Signifying Poorly Controlled Rheumatoid Arthritis.

ABSTRACT: A 74-year-old man with poorly controlled seropositive rheumatoid arthritis was referred for 18F-FDG PET/CT for follow-up of lung cancer, which demonstrated intense FDG activity in atlantoaxial, sternoclavicular, glenohumeral, and hip joints consistent with active rheumatoid arthritis. There was also unexpected intense uptake at scapulothoracic, ischiogluteal, and trochanteric bursae signifying active bursitis.

Bone Health Status of Children with Spinal Muscular Atrophy.

BACKGROUND: Spinal muscular atrophy (SMA) is a group of rare, inherited neuromuscular disorders. Bone health is often a neglected issue in children with SMA. This study aimed to evaluate the bone health status of children with SMA in Hong Kong. METHODS: This retrospective study included children with SMA who were managed in the Neuromuscular Disorder Clinics of 2 quaternary centers in Hong Kong. Bone health status was assessed by fracture history, bone mineral density (BMD) measured by dual energy X-ray absorptiometry, and serum 25-hydroxy-vitamin D (25[OH]D) level. RESULTS: Thirty-two children were included (males, 12). The median age was 10.8 years. BMD assessments were performed in 17 patients (SMA type 1=2, type 2=8, type 3=7). Low BMD was observed in 16 out of 17 patients. Four had a history of long bone fractures and were started on bisphosphonates. SMA types, age at last visit, sex, ambulation, and 25(OH)D level were not associated with fracture history or BMD Z-scores. Only one fulfilled the 2019 International Society for Clinical Densitometry (ISCD) pediatric definition of osteoporosis, with both low BMD and a history of clinically significant fracture. CONCLUSIONS: Children with SMA on disease-modifying treatments commonly had Low BMD and a history of fractures, but osteoporosis was uncommon according to the 2019 ISCD pediatric definition. A special definition of osteoporosis may be needed for this high-risk group.

Abnormal Cerebral FDG Accumulation in Acute Intracerebral and Subarachnoid Hemorrhages Due to Different Mechanisms.

ABSTRACT: Changes in cerebral glucose metabolism after acute intracranial hemorrhage have been rarely described. We present a patient with abnormal cerebral FDG accumulation in acute intracerebral and subarachnoid hemorrhages due to different mechanisms on FDG PET/CT. The patient received conservative management and died 2 months later. This case demonstrated the different mechanisms of cerebral FDG accumulation in different types of intracranial hemorrhage, which may be helpful for future research to optimize patient care.

Unexpected FDG Uptake in the Cerebral Parenchyma in Subacute Subarachnoid Hemorrhage.

ABSTRACT: Changes in cerebral glucose metabolism after subarachnoid hemorrhage have been rarely described. We present a case with subacute subarachnoid hemorrhage showing unexpected elevated FDG uptake at adjacent cerebral parenchyma on FDG PET/CT. The density of the cerebral parenchyma was normal on CT. The patient received medical management without any neurological complication.

Hepatic Superscan in Methotrexate-Associated Lymphoproliferative Disorder.

ABSTRACT: A 60-year-old man on methotrexate for treatment of adult-onset Still disease presented with acute onset of fever, pancytopenia, and deranged liver function. Besides FDG-avid lesions in spleen and skeleton, his 18 F-FDG PET/CT study showed diffuse and intense uptake in the liver with significantly suppressed heart and brain activity (reminiscent of a hepatic superscan). Subsequent biopsy confirmed the diagnosis of methotrexate-associated lymphoproliferative disorder.