Case 319: Multisystemic Smooth Muscle Dysfunction Syndrome.

HISTORY: A 7-year-old Chinese girl presented to a local hospital with a 5-day history of progressive right-sided hemiplegia, expressive aphasia, mild bulbar palsy, and reduced general responsiveness. At presentation, her Glasgow Coma Scale was 11/15 (E4 V1M6). Notably, she had two strokelike episodes approximately 7 and 3 months prior to the current episode, with headache, reduced movement, and numbness in the left hand. She also had an extensive medical history at a young age, including congenital mydriasis, patent ductus arteriosus with ligation, dysautonomia, low blood pressure, hypotonic bladder requiring intermittent catheterization, poor bowel transit, and gallstones. Her immunization record was up to date, and her development was otherwise unremarkable. Her parents and younger sibling were healthy. Her blood tests revealed a mildly increased venous lactate level at 2.3 mmol/L (normal range, 0.7-2.1 mmol/L), without acidosis. Results of a coagulopathy work-up (clotting profile and protein C, protein S, antithrombin 3, and fibrinogen levels) were normal. MRI and MR angiography of the brain were performed at presentation.

Case 319.

HISTORY: A 7-year-old Chinese girl presented to a local hospital with a 5-day history of progressive right-sided hemiplegia, expressive aphasia, mild bulbar palsy, and reduced general responsiveness. At presentation, her Glasgow Coma Scale was 11/15 (E4 V1M6). Notably, she had two strokelike episodes approximately 7 and 3 months prior to the current episode, with headache, reduced movement, and numbness in the left hand. She also had an extensive medical history at a young age, including congenital mydriasis, patent ductus arteriosus with ligation, dysautonomia, low blood pressure, hypotonic bladder requiring intermittent catheterization, poor bowel transit, and gallstones. Her immunization record was up to date, and her development was otherwise unremarkable. Her parents and younger sibling were healthy. Her blood tests revealed a mildly increased venous lactate level at 2.3 mmol/L (normal range, 0.7-2.1 mmol/L), without acidosis. Results of a coagulopathy work-up (clotting profile and protein C, protein S, antithrombin 3, and fibrinogen levels) were normal. MRI (Fig 1) and MR angiography of the brain (Fig 2) were performed at presentation.

How to Report: Hip MRI.

Writing a good magnetic resonance imaging (MRI) hip report requires a sound understanding of hip anatomy, imaging, and related pathologies. The structures of the hip most prone to pathology are the articular surfaces, labrum, subchondral bone, and gluteal tendons. Particular attention should be paid to abnormal hip morphology that is relatively common and can manifest as internal or external hip derangement. It is essential to appreciate and report the specific features of each pathology that carry clinical significance to aid patient management. This article is aimed at trainee radiologists and those less experienced with reporting hip MRI, focusing on the essential features to comment on and providing examples of terminology to use and MR images to illustrate these features.

Challenges in glucoCEST MR body imaging at 3 Tesla.

BACKGROUND: The aim of this study was to translate dynamic glucose enhancement (DGE) body magnetic resonance imaging (MRI) based on the glucose chemical exchange saturation transfer (glucoCEST) signal to a 3 T clinical field strength. METHODS: An infusion protocol for intravenous (i.v.) glucose was optimised using a hyperglycaemic clamp to maximise the chances of detecting exchange-sensitive MRI signal. Numerical simulations were performed to define the optimum parameters for glucoCEST measurements with consideration to physiological conditions. DGE images were acquired for patients with lymphomas and prostate cancer injected i.v. with 20% glucose. RESULTS: The optimised hyperglycaemic clamp infusion based on the DeFronzo method demonstrated higher efficiency and stability of glucose delivery as compared to manual determination of glucose infusion rates. DGE signal sensitivity was found to be dependent on T2, B1 saturation power and integration range. Our results show that motion correction and B0 field inhomogeneity correction are crucial to avoid mistaking signal changes for a glucose response while field drift is a substantial contributor. However, after B0 field drift correction, no significant glucoCEST signal enhancement was observed in tumour regions of all patients in vivo. CONCLUSIONS: Based on our simulated and experimental results, we conclude that glucose-related signal remains elusive at 3 T in body regions, where physiological movements and strong effects of B1 + and B0 render the originally small glucoCEST signal difficult to detect.

Pars interarticularis injury in elite athletes - The role of imaging in diagnosis and management.

Injuries of the lumbar neural arch, in particular the pars interarticularis, are widely considered to be due to abnormal bone stress secondary to repetitive loading/shearing, and are a common pathology and a main cause of lower back pain in elite athletes across a range of sports. Medical imaging plays a pivotal role in the diagnosis, monitoring and prognostication of neural arch injury. Early detection is highly desirable in the young elite athlete, as early injuries have been shown to require shorter recovery time and have a higher potential of full healing, whilst accurate grading of injury allows appropriate rehabilitation planning. Various imaging modalities are used in the diagnosis and management of pars stress injury, each with their strengths and weaknesses. There is currently a lack of general consensus over the most appropriate imaging pathway for neural arch injury in this specific group of patients. In this review article, we present an overview of neural arch injury, the various imaging modalities used and their imaging appearances with a brief pictorial review, and a proposed imaging algorithm with special considerations in the young elite athletes.

Abdominopelvic splenosis--an unusual cause of tenesmus.

Splenosis is a rare condition defined as seeding and autotransplantation of splenic tissue, typically after blunt abdominal trauma (e.g. from road traffic collision). Sites of splenosis ranging from intrathoracic to intrapelvic have been reported, and symptoms vary greatly depending on the site and size of lesions. We present the use of Tc-99m sulphur colloid SPECT/CT in diagnosing a case of multiple abdominopelvic splenosis as the cause of new-onset tenesmus and constipation, which was initially thought to be due to colorectal malignancy, 47 years following the initial abdominal trauma.

Dynamic contrast-enhanced MRI improves accuracy for detecting focal splenic involvement in children and adolescents with Hodgkin disease.

BACKGROUND: Accurate assessment of splenic disease is important for staging Hodgkin lymphoma. OBJECTIVE: The purpose of this study was to assess T2-weighted imaging with and without dynamic contrast-enhanced (DCE) MRI for evaluation of splenic Hodgkin disease. MATERIALS AND METHODS: Thirty-one children with Hodgkin lymphoma underwent whole-body T2-weighted MRI with supplementary DCE splenic imaging, and whole-body PET-CT before and following chemotherapy. Two experienced nuclear medicine physicians derived a PET-CT reference standard for splenic disease, augmented by follow-up imaging. Unaware of the PET-CT, two experienced radiologists independently evaluated MRI exercising a locked sequential read paradigm (T2-weighted then DCE review) and recorded the presence/absence of splenic disease at each stage. Performance of each radiologist was determined prior to and following review of DCE-MRI. Incorrect MRI findings were ascribed to reader (lesion present on MRI but missed by reader) or technical (lesion not present on MRI) error. RESULTS: Seven children had splenic disease. Sensitivity/specificity of both radiologists for the detection of splenic involvement using T2-weighted images alone was 57%/100% and increased to 100%/100% with DCE-MRI. There were three instances of technical error on T2-weighted imaging; all lesions were visible on DCE-MRI. CONCLUSIONS: T2-weighted imaging when complemented by DCE-MRI imaging may improve evaluation of Hodgkin disease splenic involvement.

Bone marrow mononuclear cells reduce myocardial reperfusion injury by activating the PI3K/Akt survival pathway.

OBJECTIVE: Adult bone marrow mononuclear cells (BMMNCs) can restore cardiac function following myocardial necrosis. Protocols used to date have administered cells relatively late after ischaemia/reperfusion injury, but there is the opportunity with elective procedures to infuse cells shortly after restoration of blood flow, for example after angioplasty. Our aim was therefore to try and quantify protection from myocardial injury by early infusion of BMMNCs in a rat ischaemia reperfusion (I/R) model. METHODS AND RESULTS: Male Wistar rats underwent 25 min of ischaemia followed by 2 h reperfusion of the left anterior descending coronary artery. Ten million BMMNCs were injected i.v. at reperfusion. We found BMMNCs caused a significant reduction in infarct size at 2 h when assessed by staining the area at risk with p-nitro blue tetrazolium (42% reduction, P<0.01). Apoptosis and necrosis of isolated cardiomyocytes was significantly reduced in the area at risk. Functional assessment at 7 days using echocardiography and left ventricular catheterisation showed improved systolic and diastolic function in the BMMNC treatment group (LVEF: BMMNC 71 ± 3% vs. PBS 48 ± 4%, P<0.0001). In functional studies BMMNC injected animals showed increased activation of Akt, inhibition of GSK-3ß, amelioration of p38 MAP kinase phosphorylation and NF-κB activity compared to control myocardium. Inhibition of PI3K with LY294002 abolished all beneficial effects of BMMNC treatment. Proteomic analysis also demonstrated that BMMNC treatment induced alterations in proteins within known cardioprotective pathways, e.g., heat shock proteins, stress-70 protein as well as the chaperone protein 14-3-3 epsilon. CONCLUSIONS: Early BMMNC injection during reperfusion preserves the myocardium, with evidence of reduced apoptosis, necrosis, and activation of survival pathways.