The (extended) achondroplasia foramen magnum score has good observer reliability.

BACKGROUND: Achondroplasia is the most common skeletal dysplasia. A significant complication is foramen magnum stenosis. When severe, compression of the spinal cord may result in sleep apnea, sudden respiratory arrest and death. To avoid complications, surgical decompression of the craniocervical junction is offered in at-risk cases. However, practice varies among centres. To standardize magnetic resonance (MR) reporting, the achondroplasia foramen magnum score was recently developed. The reliability of the score has not been assessed. OBJECTIVE: To assess the interobserver reliability of the achondroplasia foramen magnum score. MATERIALS AND METHODS: Base of skull imaging of children with achondroplasia under the care of Sheffield Children's Hospital was retrospectively and independently reviewed by four observers using the achondroplasia foramen magnum score. Two-way random-effects intraclass coefficient (ICC) was used to assess inter- and intra-observer reliability. RESULTS: Forty-nine eligible cases and five controls were included. Of these, 10 were scored normal, 17 had a median score of 1 (mild narrowing), 11 had a median score of 2 (effacement of cerebral spinal fluid), 10 had a score of 3 (compression of cord) and 6 had a median score of 4 (cord myelopathic change). Interobserver ICC was 0.72 (95% confidence interval = 0.62-0.81). Intra-observer ICC ranged from 0.60 to 0.86. Reasons for reader disagreement included flow void artefact, subtle T2 cord signal and myelopathic T2 cord change disproportionate to canal narrowing. CONCLUSION: The achondroplasia foramen magnum score has good interobserver reliability. Imaging features leading to interobserver disagreement have been identified. Further research is required to prospectively validate the score against clinical outcomes.

Pituitary apoplexy secondary to metastatic breast carcinoma into a gonadotroph cell adenoma of the pituitary.

A 65 year-old lady with metastatic breast cancer presented with pituitary apoplexy. Following surgery, histopathology confirmed metastatic breast carcinoma into a gonadotroph cell adenoma of the pituitary. Tumours that metastasise to a normal pituitary gland are unusual. More so, such neoplasm-to-neoplasm metastasis is extremely rare. This is, as far as we are aware, the first description of a metastasis into a gonadotroph cell pituitary adenoma presenting as apoplexy.

Avoiding skull radiographs in infants with suspected inflicted injury who also undergo head CT: "a no-brainer?"

OBJECTIVES: To assess whether head CT with 3D reconstruction can replace skull radiographs (SXR) in the imaging investigation of suspected physical abuse (SPA)/abusive head trauma (AHT). METHODS: PACS was interrogated for antemortem skeletal surveys performed for SPA, patients younger than 2 years, SXR and CT performed within 4 days of each other. Paired SXR and CT were independently reviewed. One reviewer analysed CT without and (3 months later) with 3D reconstructions. SXR and CT expert consensus review formed the gold standard. Observer reliability was calculated. RESULTS: A total of 104 SXR/CT examination pairs were identified, mean age 6.75 months (range 4 days to 2 years); 21 (20%) had skull fractures; two fractures on CT were missed on SXR. There were no fractures on SXR that were not seen on CT. For SXR and CT, respectively: PPV reviewer 1, 95% confidence interval (CI) 48-82% and 85-100%; reviewer 2, 67-98% and 82-100%; and NPV reviewer 1, 95%, CI 88-98% and 96-100%; reviewer 2, 88-97% and 88-98%. Inter- and intra-observer reliability were respectively the following: SXR, excellent (kappa = 0.831) and good (kappa = 0.694); CT, excellent (kappa = 0.831) and perfect (kappa = 1). All results were statistically significant (p < 0.001). CONCLUSIONS: CT has greater diagnostic accuracy than SXR in detecting skull fractures which is increased on concurrent review of 3D reconstructions and should be performed in every case of SPA/AHT. SXR does not add further diagnostic information and can be omitted from the skeletal survey when CT with 3D reconstruction is going to be, or has been, performed. KEY POINTS: • Head CT with 3D reconstruction is more sensitive and specific for the diagnosis of skull fractures. • Skull radiographs can be safely omitted from the initial skeletal survey performed for suspected physical abuse when head CT with 3D reconstruction is going to be, or has been, performed.

Added value of arterial spin labeling magnetic resonance imaging in pediatric neuroradiology: pitfalls and applications.

Arterial spin labeling is a noninvasive, non-gadolinium-dependent magnetic resonance imaging (MRI) technique to assess cerebral blood flow. It provides insight into both tissue metabolic activity and vascular supply. Because of its non-sensitivity toward blood-brain barrier leakage, arterial spin labeling is also more accurate in cerebral blood flow quantification than gadolinium-dependent methods. The aim of this pictorial essay is to promote the application of arterial spin labeling in pediatric neuroradiology. The authors provide information on artifacts and pitfalls as well as numerous fields of application based on pediatric cases.

Do Optic Canal Dimensions Measured on CT Influence the Degree of Papilloedema and Visual Dysfunction in Idiopathic Intracranial Hypertension?

A recent study found that increased optic canal area on magnetic resonance imaging was associated with worse papilloedema in idiopathic intracranial hypertension (IIH). We repeated this study using more accurate computerized tomography derived measurements. Optic canal dimensions were measured from 42 IIH patients and 24 controls.  These were compared with papilloedema grade.  There was no correlation between any of the optic canal measurements and papilloedema grade and no significant difference in optic canal measurements between patients and controls. Our results cast doubt on the existing literature regarding the association between optic canal size and the degree of papilloedema in IIH. CT delineates bony anatomy more accurately than MRI and our CT-derived optic canal measurements cast doubt on the existing literature regarding the association between optic canal size and the degree of Papilloedema in IIH.

Initial experience of an investigational 3T MR scanner designed for use on neonatal wards.

OBJECTIVES: MR imaging of neonates is difficult for many reasons and a major factor is safe transport to the MR facilities. In this article we describe the use of a small, investigational 3-T MR customised for brain imaging and sited on a neonatal unit of a tertiary centre in the UK, which is in contrast to a 300-m journey to the whole-body MR scanner used at present for clinical cases. METHODS: We describe our methods for preparing babies for safe transport and scanning on an investigational 3-T MR scanner on a neonatal unit and the development of appropriate MR sequences. The MR scanner does not have CE marking at present so this early development work was undertaken on normal neonates whose parents consented to a research examination. RESULTS: Fifty-two babies were scanned and there were no serious adverse events. The MR examinations were considered to be diagnostically evaluable in all 52 cases and in 90% the imaging was considered to be at least as good as the quality obtained on the 1.5-T scanner currently used for clinical cases. CONCLUSION: We have shown that this investigational 3-T MR scanner can be used safely on a neonatal unit and we have refined the MR sequences to a point that they are clinically usable. KEY POINTS: • Access to neonatal MR imaging is limited. • We describe an investigational 3-T MR scanner site on a neonatal unit. • The scanner produces images suitable for clinical practice.

Pituitary tumour apoplexy within prolactinomas in children: a more aggressive condition?

OBJECTIVES: To evaluate clinical presentations, diagnosis and management of paediatric patients presenting with pituitary apoplexy. METHODS: A retrospective case series describing a cohort of paediatric patients presenting with this condition from 2010-2016 to a tertiary referral children's hospital in the United Kingdom. RESULTS: Pituitary apoplexy is a rare condition that seems to have a higher relative incidence in children than adults. Our series suggests that pituitary apoplexy in paediatric patients with adenomas appears more common than previously described. All our patients required surgery, either as an acute or delayed procedure, for visual compromise. Two patients had commenced growth hormone (GH) for GH deficiency two weeks prior to the onset of pituitary apoplexy. CONCLUSIONS: With only a limited number of published case reports surrounding this topic our case series contributes to help further understand and manage this condition.

Moyamoya Syndrome Associated With Hereditary Spherocytosis: An Emerging Clinical Entity.

Moyamoya syndrome is an unusual cerebrovascular disorder, which has rarely been reported in association with hereditary spherocytosis. We present the case of a 6-year-old boy with hereditary spherocytosis who was diagnosed with Moyamoya syndrome following a stroke. We discuss why these conditions may coexist and briefly outline the management of such children.

Quantification of structural changes in the corpus callosumin children with profound hypoxic-ischaemic brain injury.

BACKGROUND: Birth-related acute profound hypoxic-ischaemic brain injury has specific patterns of damage including the paracentral lobules. OBJECTIVE: To test the hypothesis that there is anatomically coherent regional volume loss of the corpus callosum as a result of this hemispheric abnormality. MATERIALS AND METHODS: Study subjects included 13 children with proven acute profound hypoxic-ischaemic brain injury and 13 children with developmental delay but no brain abnormalities. A computerised system divided the corpus callosum into 100 segments, measuring each width. Principal component analysis grouped the widths into contiguous anatomical regions. We conducted analysis of variance of corpus callosum widths as well as support vector machine stratification into patient groups. RESULTS: There was statistically significant narrowing of the mid-posterior body and genu of the corpus callosum in children with hypoxic-ischaemic brain injury. Support vector machine analysis yielded over 95% accuracy in patient group stratification using the corpus callosum centile widths. CONCLUSION: Focal volume loss is seen in the corpus callosum of children with hypoxic-ischaemic brain injury secondary to loss of commissural fibres arising in the paracentral lobules. Support vector machine stratification into the hypoxic-ischaemic brain injury group or the control group on the basis of corpus callosum width is highly accurate and points towards rapid clinical translation of this technique as a potential biomarker of hypoxic-ischaemic brain injury.

Diffuse intrinsic pontine glioma: is MRI surveillance improved by region of interest volumetry?

BACKGROUND: Paediatric diffuse intrinsic pontine glioma (DIPG) is noteworthy for its fibrillary infiltration through neuroparenchyma and its resultant irregular shape. Conventional volumetry methods aim to approximate such irregular tumours to a regular ellipse, which could be less accurate when assessing treatment response on surveillance MRI. Region-of-interest (ROI) volumetry methods, using manually traced tumour profiles on contiguous imaging slices and subsequent computer-aided calculations, may prove more reliable. OBJECTIVE: To evaluate whether the reliability of MRI surveillance of DIPGs can be improved by the use of ROI-based volumetry. MATERIALS AND METHODS: We investigated the use of ROI- and ellipsoid-based methods of volumetry for paediatric DIPGs in a retrospective review of 22 MRI examinations. We assessed the inter- and intraobserver variability of the two methods when performed by four observers. RESULTS: ROI- and ellipsoid-based methods strongly correlated for all four observers. The ROI-based volumes showed slightly better agreement both between and within observers than the ellipsoid-based volumes (inter-[intra-]observer agreement 89.8% [92.3%] and 83.1% [88.2%], respectively). Bland-Altman plots show tighter limits of agreement for the ROI-based method. CONCLUSION: Both methods are reproducible and transferrable among observers. ROI-based volumetry appears to perform better with greater intra- and interobserver agreement for complex-shaped DIPG.

Outcomes of percutaneous vertebroplasty in multiple myeloma: a tertiary neurosciences experience with long-term follow-up.

Background: Multiple myeloma is diagnosed in 5,800 people in the United Kingdom (UK) each year with up to 64% having vertebral compression fractures at the time of diagnosis. Painful vertebral compression fractures can be of significant detriment to patients' quality of life. Percutaneous vertebroplasty aims to provide long-term pain relief and stabilize fractured vertebrae. Methods and materials: Data was collected from all cases of percutaneous vertebroplasty performed on patients with multiple myeloma from November 2017 to January 2019. Pain scores were measured using the Visual Analogue Scale (VAS) and Oswestry Disability Index (ODI) pre-procedure, 2 months post procedure and 4 years post-procedure. Procedure related complications and analgesia use were also documented. Results: 22 patients were included with a total of 119 vertebrae treated. Patients reported a significant improvement in overall pain score with a median pre-procedure VAS of 8 and a median post-procedure VAS of 3.5 (p<0.0001). There was a median pre-procedure ODI score of 60% and a median post-procedure ODI score of 36% (p<0000.1). There was improvement across all ODI domains and a 77% reduction in analgesic requirement. There were small cement leaks into paravertebral veins or endplates at 15 levels (12%) which were asymptomatic. There were 8 responders to the long-term follow-up questionnaire at 4 years. This demonstrated an overall stable degree of pain relief in responders with a median VAS of 3.5 and median ODI of 30%. Conclusion: At this center, vertebroplasty has been shown to reduce both VAS and ODI pain scores and reduce analgesia requirements in patients with VCFs secondary to multiple myeloma with long lasting relief at 4 years post-procedure.

Comparison of endoscopic and microscopic trans-sphenoidal pituitary surgery: early results in a single centre.

INTRODUCTION: Pituitary surgery has seen a recent shift from a microscopic to an endoscopic trans-sphenoidal approach. We present our early experience with endoscopic surgery and compare the outcome with our recent microscopic experience. METHODS: From January 2008 until present time, 80 consecutive patients underwent trans-sphenoidal pituitary surgery in our institution. Until September 2009, all patients had a microscopic trans-septal approach. After this time, the patients underwent endoscopic trans-sphenoidal surgery. All patients underwent pre- and post-operative MRI and full endocrinological evaluation. Data was collected prospectively including tumour volume, endocrine function, visual function, length of stay and complications. RESULTS: There were 40 patients in each group. In the microscopic group, there were 26 non-functioning tumours and 14 functioning tumours. In the endoscopic group, there were 24 non-functioning and 16 functioning tumours. There were significantly better results in terms of tumour resection (p = 0.002) and remission (p = 0.018) in the endoscopic group. In this group there was also a lower incidence of CSF leaks and a shorter length of stay for secreting tumours (p = 0.005). 1 patient in the endoscopic group died at day 43 post-operatively, having initially presented in a poor clinical state with pituitary apoplexy. CONCLUSION: Microscopic trans-sphenoidal surgery remains the benchmark for future surgical techniques. Our early results suggest that endoscopic trans-sphenoidal surgery provides favourable results in both tumour resection and control of secreting tumours in comparison with microscopic surgery. Further longer-term evaluation is required to ensure the outcome of endoscopic surgery.

Craniospinal abnormalities and neurologic complications of osteogenesis imperfecta: imaging overview.

Osteogenesis imperfecta is a rare genetic disorder that leads to progressive skeletal deformities due to deficits in type I collagen, the main pathophysiologic effect of the disease. In addition, it may lead to a wide range of associated neurologic abnormalities: The central nervous system is usually involved because of softening of bone at the base of the skull, with resultant upward migration of the upper cervical spine and odontoid process into the skull base. Upward migration of the spine may cause compression of the brainstem, mechanical impingement of the spinal canal with restriction of cerebrospinal fluid circulation, and impingement of the cranial nerves. Osteogenesis imperfecta also may directly involve neurovascular structures, leading to cavernous fistulas of the carotid artery, dissection of the cervical arteries, and cerebral aneurysms. The brain parenchyma is frequently affected by the disease, with manifestations including cerebral atrophy, communicating hydrocephalus, and cerebellar hypoplasia. The imaging features of the disorder vary as widely as its clinical manifestations, depending on the severity of disease. Severe forms accompanied by debilitating skeletal fractures and progressive neurologic impairments may lead to perinatal death, whereas milder asymptomatic forms might cause only a modest reduction in life span. The most important advance in medical therapy for osteogenesis imperfecta has been the introduction of bisphosphonate therapy to slow the resorption of bone in patients with moderate to severe forms of the disease (ie, type III or IV). In some patients, neurosurgery may be necessary to correct the effects of severe basilar invagination by the odontoid process.

Unilateral periventricular leukomalacia in association with pyruvate dehydrogenase deficiency.

Pyruvate dehydrogenase (PDH) deficiency is a major cause of primary lactic acidosis and neurological dysfunction in infancy and early childhood. A deficiency of PDH E1 alpha, a subunit of the PDH complex, is a prominent cause of congenital lactic acidosis. We describe a female infant born at term and delivered by emergency Caesarean section because of fetal distress. There was no parental consanguinity. She presented at 5 months of age with failure to thrive, microcephaly, hypertonia, and developmental impairment. Her plasma and cerebrospinal fluid lactate were raised. She had raised plasma pyruvate with a normal lactate-pyruvate ratio. Magnetic resonance imaging of the brain showed a focal dilatation of the right lateral ventricle with unilateral periventricular leukomalacia (PVL) with subependymal cyst. Skin fibroblast culture assay revealed PDH deficiency, confirmed by mutation analysis of the E1 alpha subunit. At 18 months of age, she has hypertonia and global impairment and is making slow progress. Denver II assessment showed delay in gross motor, fine motor, adaptive, personal, social, and language categories. She has been treated with dichloroacetate and a ketogenic diet since the age of 10 and 13 months respectively, without any side effects. To our knowledge, unilateral PVL as a neuroradiological feature has not been described in children with PDH deficiency. PDH deficiency should be considered as a differential diagnosis if PVL is unilateral and if the perinatal history is not typical of PVL.

Predicting neurodevelopmental outcomes in fetuses with isolated mild ventriculomegaly.

BACKGROUND: Fetal ventriculomegaly is the the most common intracranial abnormality detected antenatally. When ventriculomegaly is mild and the only, isolated, abnormality detected (isolated mild ventriculomegaly (IMVM)) the prognosis is generally considered to be good. We aim to determine if there are features on in utero MRI (iuMRI) that can identify fetuses with IMVM who have lower risks of abnormal neurodevelopment outcome. METHODS: We studied cases recruited into the MRI to enhance the diagnosis of fetal developmental brain abnormalities in utero (MERIDIAN) study, specifically those with: confirmed IMVM, 3D volume imaging of the fetal brain and neurodevelopmental outcomes at 3 years. We explored the influence of sex of the fetus, laterality of the ventriculomegaly and intracranial compartmental volumes in relation to neurodevelopmental outcome. FINDINGS: Forty-two fetuses met the criteria (33 male and 9 female). There was no obvious correlation between fetal sex and the risk of poor neurodevelopmental outcome. Unilateral IMVM was present in 23 fetuses and bilateral IMVM in 19 fetuses. All fetuses with unilateral IMVM had normal neurodevelopmental outcomes, while only 12/19 with bilateral IMVM had normal neurodevelopmental outcomes. There was no obvious correlation between measure of intracranial volumes and risk of abnormal developmental outcomes. INTERPRETATION: The most important finding is the very high chance of a good neurodevelopmental outcome observed in fetuses with unilateral IMVM, which is a potentially important finding for antenatal counselling. There does not appear to be a link between the volume of the ventricular system or brain volume and the risk of poor neurodevelopmental outcome.

The use of MR imaging and spectroscopy of the brain in children investigated for developmental delay: what is the most appropriate imaging strategy?

OBJECTIVES: Developmental delay is a common problem in paediatric practice and many children with developmental delay are referred for MR imaging. Our study was performed as part of a continuing audit process to optimise our MR protocol and case selection. MATERIALS AND METHODS: We performed MR imaging and spectroscopy protocol on 157 children with developmental delay. We analysed the effect of these interventions by looking at the overall detection rate of relevant pathology and in particular subgroups of the children. RESULTS: 71% of the children had normal MR imaging, 10% had non-specific findings and 19% had specific abnormalities on MR imaging. The overall risk of having a specific structural abnormality with isolated developmental was 7.5% but if other neurological symptoms/signs were present the risk was 28%. Two children had abnormal spectroscopic findings, one with tuberous sclerosis and the other with absent brain creatine. CONCLUSION: Case selection for MR imaging is important in children with developmental delay. The best strategies for selecting children for MR are either; not performing MR with developmental delay in one domain only or performing MR with developmental delay in three or four domains or if there are other neurological features.

Pediatric Cerebral Cavernous Malformations.

Cerebral cavernous malformations are the second most common vascular malformations in the central nervous system, and over one-third are found in children. Lesions may be solitary or multiple, be discovered incidentally, be sporadic, or be secondary to familial cavernomatosis or radiation therapy. Children may present with focal seizures, intracranial hemorrhage, or focal neurological deficits without radiological evidence of recent hemorrhage. We present several children with cerebral cavernous malformations and explore the challenges of their diagnosis in children, their key imaging features, the role of follow-up imaging, and their subsequent management including stereotactic radiosurgery and microsurgical resection. Individual patient risk stratification is advocated for all affected children and their families.

Imaging in acute ischaemic stroke: essential for modern stroke care.

Stroke is the second most common cause of death worldwide and the third most common in the UK. 'Time is brain' in ischaemic stroke; early reperfusion has been shown to lead to improved clinical outcomes, yet the majority of patients with acute stroke do not attend in time for thrombolysis as it is currently licensed, hence the interest in trials extending the therapeutic window. Defining the ischaemic penumbra is of crucial importance in choosing the appropriate patients for thrombolytic therapy who attend outside the optimal therapeutic window. Integrated stroke imaging, including demonstration of potentially salvageable tissue with either MR perfusion/diffusion studies or CT perfusion, is increasingly likely to play a central role in future management strategies and widening of the potential therapeutic window. This review highlights the basic imaging findings of acute stroke and discusses the role of advanced CT and MR techniques as well as options for vascular imaging.

Imaging in childhood scoliosis: a pictorial review.

Childhood scoliosis is a common clinical entity with a number of different causes. In the majority of cases, the scoliosis is idiopathic, but it may be the manifestation of an occult spinal pathology. The clinical history and examination may elicit certain worrying features such as pain, neurological symptoms or an atypical curve pattern. These findings should prompt advanced imaging, as early and accurate detection of an underlying cause allows optimal planning and timing of surgery and helps reduce associated risks. The most common occult pathologies detected by advanced imaging are Arnold Chiari malformations, syringohydromyelia and closed spinal dysraphism such as diastematomyelia. Advanced imaging techniques, in particular multiplanar MRI, are also increasingly requested in children with known congenital scoliosis associated with spinal dysraphism and developmental causes of scoliosis such as neurofibromatosis and Klippel-Feil syndrome, as it allows superior delineation of the spinal column without the radiation risk. This review aims to examine the different imaging techniques currently used in the evaluation of scoliosis and provide a pictorial summary of the more common causes and associations.

Intracranial non-Langerhans cell histiocytosis presenting as an isolated intraparenchymal lesion.

Non-Langerhans cell histiocytosis in the absence of cutaneous or other organ involvement is very rare. A Caucasian boy age 3 years 11 months presented with episodes of recurrent right-side seizures over 2 weeks. Brain CT and MR imaging showed a single enhancing left frontal lobe lesion. Stereotactic biopsy was performed and histological examination showed diffuse infiltrate of macrophages with foamy cytoplasm. Four months later there was recurrence of seizure activity despite anti-epileptic medication and a repeat MR scan showed a persistent enhancing lesion in the left frontal lobe. Histological examination of the resection specimen resembled juvenile xanthogranuloma (JXG) involving the central nervous system. In the absence of skin lesions a diagnosis of non-Langerhans cell histiocytosis was made. The child made a full recovery following surgery with resolution of his symptoms.