Hepatic steatosis: Qualitative and quantitative sonographic assessment in comparison to histology.

Introduction: Globally, B-mode ultrasound is the most common modality used for the diagnosis of hepatic steatosis. We aimed to assess the correlation between qualitative liver ultrasound parameters, attenuation imaging (ATI) and histopathology-diagnosed steatosis grade obtained from liver biopsy. Our secondary aim was to examine the interobserver variability of qualitative ultrasound features. Methods: A retrospective cohort study was performed which included adult patients (age ≥ 18 years) who had same-day liver ultrasound, ATI and liver biopsy for grading hepatic steatosis severity between 2018 and 2022. The qualitative US features for hepatic steatosis were independently scored by three radiologists and interobserver variability was examined. Histologic steatosis grade, ATI and qualitative ultrasound parameters were compared. Results: Ninety patients were included; 67% female with a median age of 54 (IQR 39-65) years. The radiologist's overall impression had the highest correlation (very strongly correlated) with histologic steatosis grade (r = 0.82, P < 0.001). ATI coefficient and all qualitative ultrasound B-mode features except for liver echotexture and focal fat sparing were strongly correlated with histologic steatosis grade (r ≥ 0.70, P < 0.001). Most qualitative ultrasound features had good agreement between observers (Kappa statistic 0.61-1.0, P < 0.001), (Kendall coefficient 0.92, P < 0.001). Conclusion: The examined qualitative ultrasound parameters and ATI had good-excellent performance for diagnosing clinically significant hepatic steatosis; however, the radiologist's overall impression had the best correlation with histologic steatosis grade. Our findings suggest an ongoing role for qualitative liver ultrasound assessment of hepatic steatosis despite the emergence of newer quantitative measures.

Hirayama disease: the importance of flexion imaging.

Hirayama disease is a rare cervical myelopathy characterised by asymmetrical upper limb weakness and muscle atrophy in the forearm and hand. MRI of the cervical spine plays an essential role in diagnosis, however, the characteristic findings are often only seen when the patient is imaged with the neck in flexion. We present a case of a 15-year-old male who presented with left forearm and hand weakness with muscle wasting. An MRI of the cervical spine with the neck in a neutral position demonstrated atrophy of the spinal cord with intrinsic signal abnormality between C5 and C7. Further imaging with the patient's neck in flexion demonstrated the hallmark features of Hirayama disease. There was anterior displacement of the thecal sac and spinal cord, and an enlarged, crescent-shaped dorsal epidural space which enhanced following i.v. gadolinium administration. The atrophic segment of cord contacted the posterior vertebral bodies when the neck was in full flexion. This case highlights the importance of imaging patients suspected of having this entity with the neck in full flexion in order to make a diagnosis.

Imaging of patients with multiple myeloma and associated plasma cell disorders: consensus practice statement by the Medical Scientific Advisory Group to Myeloma Australia.

Imaging modalities for multiple myeloma (MM) have evolved to enable earlier detection of disease. Furthermore, the diagnosis of MM requiring therapy has recently changed to include disease prior to bone destruction, specifically the detection of focal bone lesions. Focal lesions are early, abnormal areas in the bone marrow, which may signal the development of subsequent lytic lesions that typically occur within the next 18-24 months. Cross-sectional imaging modalities are more sensitive for the detection and monitoring of bone and bone marrow disease and are now included in the International Myeloma Working Group current consensus criteria for initial diagnosis and treatment response assessment. The aim of this consensus practice statement is to review the evidence supporting these modalities. A more detailed Position Statement can be found on the Myeloma Australia website.

Sonographic findings in mid-aortic syndrome.

Mid-aortic syndrome (MAS) is an uncommon condition characterised by narrowing of the distal descending thoracic or abdominal aorta. While CT, MR and conventional angiography findings in MAS are well described, there have been very few cases which clearly document the sonographic features of this condition. This case report demonstrates the utility of ultrasound in the investigation of MAS and summarises the current literature surrounding the condition.

Alcoholic pontine myelinolysis: beware the stroke mimic.

Central pontine myelinolysis (CPM), often referred to as osmotic demyelination syndrome, is most commonly seen in the setting of rapid correction of hyponatraemia. Although imaging is the key to diagnosis, conventional CT and MRI findings often lag the clinical manifestations and characteristic MRI changes may be delayed by up to 14 days. We present a case of a 45-year-old female with an extensive history of alcohol misuse and malnutrition who presented with left hemiparesis, initially suspected to be a stroke. This was following a recent hospital admission when she was managed for Wernicke's encephalopathy and treated with electrolyte and vitamin replacement. As part of a "code stroke" protocol, CT was initially performed. The initial non-contrast CT brain and CT angiogram of the intracranial arteries were normal, but a CT brain perfusion study demonstrated increased pontine blood flow. A subsequent MRI of the brain confirmed CPM, which was congruent with her clinical course. This case highlights the importance of osmotic demyelination as a stroke mimic. CPM should be considered in alcoholic patients with neurological impairment regardless of serum sodium. To our knowledge, this is the first published case which illustrates CT perfusion changes in CPM. MRI, however, remains essential for diagnosis.