(What's the story) morning glory? MRI findings in morning glory disc anomaly.

PURPOSE: Morning glory disc anomaly (MGDA) is a rare congenital ophthalmologic disorder. Historically it has been diagnosed fundoscopically, with little in the literature regarding its imaging findings. The purpose of this study is to further characterize the orbital and associated intracranial magnetic resonance imaging (MRI) findings of MGDA in our tertiary pediatric center. METHODS: A retrospective review was performed of fundoscopically-diagnosed cases of MGDA, that had been referred for MRI. All MRI studies were scrutinized for orbital and other intracranial abnormalities known to occur in association with MGDA. RESULTS: 18 of 19 cases of MGDA showed three characteristic MRI findings: funnel-shaped morphology of the posterior optic disc, abnormal soft tissue associated with the retrobulbar optic nerve, and effacement of adjacent subarachnoid spaces. The ipsilateral (intraorbital) optic nerve was larger in one patient and smaller in six. The ipsilateral optic chiasm was larger in two patients and smaller in one. CONCLUSION: This study represents a comprehensive radiological-led investigation into MGDA. It describes the most frequently-encountered MRI findings in MGDA and emphasizes the importance of MRI in this cohort, i.e., in distinguishing MGDA from other posterior globe abnormalities, in assessing the visual pathway, and in screening for associated intracranial abnormalities - skull base/cerebral, vascular, and facial. It hypothesizes neurocristopathy as an underlying cause of MGDA and its associations. Caliber abnormalities of the ipsilateral optic nerve and chiasm are a frequent finding in MGDA. Optic pathway enlargement should not be labeled "glioma". (239/250).

Neuroimaging manifestations of paediatric histiocytoses.

Histiocytoses are rare multi-system disorders marked by abnormal histiocyte cell proliferation, affecting children with diverse clinical presentations. Classified into five groups in 2016, including Langerhans-related (L), cutaneous (C), malignant (M), Rosai-Dorfman disease (R) and haemophagocytic lymphohistiocytosis (H), newer entities such as ALK-positive histiocytosis have also emerged, heralding the era of molecular (sub)classification. Common entities include Langerhans cell histiocytosis (LCH), Erdheim-Chester disease (ECD), Rosai-Dorfman disease (RDD) and haemophagocytic lymphohistiocytosis (HLH). This pictorial essay aids radiologists in recognising and differentiating paediatric histiocytoses based on unique neuroimaging features.

Diffuse paediatric cerebellar glioma: two identical imaging phenotypes of an extremely rare entity with disparate pathology.

Although the posterior fossa is a common location for paediatric brain tumours [1], diffuse glioma isolated to the cerebellum is an extremely rare imaging entity. Only two cases of isolated diffuse paediatric cerebellar glioma have been reported in the English language to the best of our knowledge [2, 3], and only one of these cases had a similar imaging phenotype to our cases [3]. Although somewhat similar to Lhermitte-Duclos (dysplastic gangliocytoma of the cerebellum), the appearances are distinct from other neoplastic entities of the paediatric posterior fossa. Clinical presentation and neurological examination findings are vital however to help differentiate other diffuse pathologies involving the cerebellum such as rhombencephalitis. Presented here are two diffuse cerebellar gliomas in children under the age of 3 with near identical imaging phenotypes demonstrating differing histological and molecular genetic profiles.

Magnetic resonance imaging patterns of paediatric brain infections: a pictorial review based on the Western Australian experience.

Paediatric brain infections are relatively uncommon, but it is important for radiologists to recognise the disease and provide accurate differential diagnoses. Magnetic resonance imaging (MRI) plays an important role in determining the most likely causative pathogen-either in the setting of an unwell child with acute infectious encephalitis, or in the evaluation of a child for sequela of prior infection. Image analysis can, however, be difficult since a particular pathogen can cause variable MRI findings across different geographic environments, and conversely, a particular appearance on MRI may be caused by a variety of pathogens. This educational review aims to identify some of the key MRI patterns seen in paediatric brain infections and present example cases encountered in Western Australia. Based on (i) the predominant type of signal abnormality (restricted diffusion versus T2 hyperintensity) and (ii) the distribution of signal abnormality throughout the brain, this review presents a framework of six key MRI patterns seen in paediatric brain infections, with an emphasis on acute infectious encephalitis. There is general utility to these MRI patterns-each suggestive of a group of likely diagnostic possibilities which can be calibrated according to institution and local environment. The pattern-based framework of this review can be easily transitioned into daily radiological practice, and we hope it facilitates the formation of accurate differential diagnoses in paediatric brain infections.

Myelin oligodendrocyte glycoprotein antibody-associated bilateral optic neuritis with unilateral prepapillary vitreous hemorrhage.

We present a case of bilateral myelin oligodendrocyte glycoprotein antibody optic neuritis (MOG-ON) with unilateral vitreous hemorrhage in a 6-year-old boy. Multidisciplinary team care, including extensive investigations and prolonged follow-up, excluded alternative causes of vitreous hemorrhage. Early suspicion and diagnosis of MOG-ON led to timely intravenous methylprednisolone treatment, with protracted oral steroid taper, resulting in complete resolution of optic nerve swelling, vitreous hemorrhage, and visual function.

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.

Enhancement patterns of the normal facial nerve on three-dimensional T1W fast spin echo MRI.

OBJECTIVES: With increasing neuroimaging applications of contemporary three-dimensional T1W fast spin echo (3D T1W FSE) sequences, it was aimed to reappraise the normal patterns of skull base facial nerve gadolinium enhancement. METHODS: Pre- and post-gadolinium 3D T1W fast spin echo imaging studies (n = 64) were retrospectively analysed in patients without suspected facial nerve pathology. Two independent observers scored the signal at each of six skull base facial nerve segments. Wilcoxon signed-rank test was used to compare changes in signal between pre- and post-gadolinium sequences at each location, and how this differed between proprietary sequences or between the pairs of facial nerves. RESULTS: There was significant enhancement at the fundal canalicular (16%), geniculate ganglion (96%), tympanic (45%) and mastoid (38%) facial nerve segments (p < 0.05). Two different proprietary sequences demonstrated similar patterns of enhancement and there was symmetry between the two sides. CONCLUSIONS: There is a differing pattern of normal facial nerve enhancement on contemporary 3D T1W FSE sequences compared to previous studies of 2D T1W SE imaging and fundal canalicular enhancement may be physiological. ADVANCES IN KNOWLEDGE: This is the first study to evaluate patterns of normal facial nerve enhancement using contemporary 3D T1W FSE MRI sequences.

Spectrum of neuroimaging findings post-proton beam therapy in a large pediatric cohort.

PURPOSE: Proton beam therapy (PBT) is now well established for the treatment of certain pediatric brain tumors. The intrinsic properties of PBT are known to reduce long-term negative effects of photon radiotherapy (PRT). To better understand the intracranial effects of PBT, we analyzed the longitudinal imaging changes in a cohort of children with brain tumors treated by PBT with clinical and radiotherapy dose correlations. MATERIALS AND METHODS: Retrospective imaging review of 46 patients from our hospital with brain tumors treated by PBT. The imaging findings were correlated with clinical and dose parameters. RESULTS: Imaging changes were assessed by reviewing serial magnetic resonance imaging (MRI) scans following PBT over a follow-up period ranging from 1 month to 7 years. Imaging changes were observed in 23 patients undergoing PBT and categorized as pseudoprogression (10 patients, 43%), white matter changes (6 patients, 23%), parenchymal atrophy (6 patients, 23%), and cerebral large vessel arteriopathy (5 patients, 25%). Three patients had more than one type of imaging change. Clinical symptoms attributable to PBT were observed in 13 (28%) patients. CONCLUSION: In accordance with published literature, we found evidence of varied intracranial imaging changes in pediatric brain tumor patients treated with PBT. There was a higher incidence (10%) of large vessel cerebral arteriopathy in our cohort than previously described in the literature. Twenty-eight percent of patients had clinical sequelae as a result of these changes, particularly in the large vessel arteriopathy subgroup, arguing the need for angiographic and perfusion surveillance to pre-empt any morbidities and offer potential neuro-protection.

Incidental detection of late presenting co-arctation of the aorta on chest x-ray: the importance of rib notching.

A 31-year-old obese male presented to the emergency department with symptoms and signs suggestive of a viral upper respiratory tract illness with a background of low exercise tolerance. Rib notching was identified on plain film chest radiography and subsequent CT of the thorax identified a moderately tight 2-mm juxta-ductal co-arctation of the aorta with multiple enlarged chest wall collaterals. The patient underwent a two-stage percutaneous procedure involving stent insertion and angioplasty up to 16 mm with significant improvement in exercise capacity and a modest reduction in blood pressure.

Lupus mastitis: a mimicker of breast carcinoma.

The authors present a case of lupus mastitis which was initially diagnosed following an incisional biopsy of a breast lump, with similar pathology found 2 years later after an ultrasound guided biopsy of the same lump. The woman had been diagnosed 7 years before with systemic lupus erythematosus. The radiological and pathological features are presented in this report with discussion of similar cases in the literature.

Primary angiosarcoma of the bladder in a young female.

Our case report pertains to a 32-year-old woman initially presenting with left flank pain and gross haematuria throughout her urinary stream. CT of her kidney/ureter/bladder (CT KUB) revealed ureteric dilatation to the level of the bladder without evidence of renal calculus and subsequently a stent was inserted. She represented a month later with contralateral flank pain, and a transuretheral resection of bladder tumour was performed. Histopathological diagnosis was epithelioid angiosarcoma. Further imaging (MRI pelvis) revealed that the tumour arose from the posterior bladder wall with local invasion and regional lymph node metastasis. Ifosfamide and epirubicin chemotherapy with single-fraction radiotherapy induced significant reduction in tumour bulk, although this initial response was followed by the development of symptoms suggestive of disease progression. She died 19 months after initial diagnosis with persistent pulmonary and vertebral metastases although no autopsy was performed.

Nyctalopia: the sequelae of hypovitaminosis A.

We present a case of night blindness due to vitamin A deficiency in a gentleman who had previously undergone a pancreaticoduodenostomy 10 years ago. The deficiency was attributed self-cessation of his pancreatic supplements without being aware of the possible consequences. The diagnosis and management of this patient is presented here, along with a discussion of similar cases in the literature.