The evolution of pulmonary function in childhood onset Mucopolysaccharidosis type I.

Respiratory outcomes in Mucopolysaccharidosis Type I (MPS I), have mainly focused on upper airway obstruction, with the evolution of the restrictive lung disease being poorly documented. We report the long-term pulmonary function outcomes and examine the potential factors affecting these in 2 cohorts of MPS I patients, those who have undergone Haematopoietic Stem Cell Transplantation (HSCT) and those treated with Enzyme Replacement Therapy (ERT). The results were stratified using the American Thoracic Society (ATS) guidelines. 66 patients, capable of adequately performing testing, were identified by a retrospective case note review, 46 transplanted (45 Hurler, 1 Non-Hurler) and 20 having ERT (17 Non-Hurler and 3 Hurler diagnosed too late for HSCT). 5 patients died; 4 in the ERT group including the 3 Hurler patients. Overall 14% of patients required respiratory support (non-invasive ventilation (NIV) or supplemental oxygen)) at the end of follow up. Median length of follow-up was 12.2 (range = 4.9-32) years post HSCT and 14.34 (range = 3.89-20.4) years on ERT. All patients had restrictive lung disease. Cobb angle and male sex were significantly associated with more severe outcomes in the HSCT cohort, with 49% having severe to very severe disease. In the 17 Non-Hurler ERT treated patients there was no variable predictive of severity of disease with 59% having severe to very severe disease. During the course of follow up 67% of the HSCT cohort had no change or improved pulmonary function as did 52% of the ERT patients. However, direct comparison between therapeutic modalities was not possible. This initial evidence would suggest that a degree of restrictive lung disease is present in all treated paediatrically diagnosed MPS I and is still a significant cause of morbidity, though further stratification incorporating diffusing capacity for carbon monoxide (DLCO) is needed.

Outcomes from 18 years of cervical spine surgery in MPS IVA: a single centre's experience.

PURPOSE: This study examines the long-term outcomes of paediatric Morquio (MPS IVA) patients undergoing cervical spine surgery and evaluates the factors that impacting this. METHODS: A retrospective review was performed on all MPS IVA patients undergoing cervical spine surgery, since the introduction of standardised neuroradiological screening. The impact of preoperative neurological status, growth, genotype and radiological status on outcome is assessed, whilst long-term surgical, radiological and neurological outcomes are documented. RESULTS: Twenty-six of the eighty-two MPS IVA patients (31%) reviewed underwent cervical spine surgery at a median age of 6.1 years (range, 1.45 to 15.24). Preoperatively, cord signal change was seen in 11 patients with 5 being myelopathic; however, 6 clinically manifesting patients had no overt cord signal change. Postoperatively, none of the 14 preoperatively clinically asymptomatic patients followed long term progressed neurologically during a median follow-up of 77.5 months (range = 18-161). Of the ten preoperatively clinically symptomatic patients who were followed up for the same duration, seven continued to deteriorate, two initially improved and one remained stable. Radiological follow-up performed for a median duration of 7 years (range = 0.5-16) has shown a degree of stenosis at the level immediately caudal to the termination of the graft in 76% of patients, though only one has become clinically symptomatic and required revision. CONCLUSIONS: Once clinically elicitable neurological signs become evident in patients with MPS IVA, they tend to progress despite surgical intervention. Referring clinicians should also not be falsely reassured by the lack of T2 spinal cord signal change but should consider surgical intervention in the face of new clinical symptomology or radiological signs of progressive canal stenosis or instability.

Likelihood of persistent GH deficiency into late adolescence: relationship to the presence of an ectopic or normally sited posterior pituitary gland.

OBJECTIVES: The presence of an ectopic posterior pituitary gland (EPP) in childhood is associated with isolated GH deficiency (IGHD) and multiple pituitary hormone deficiency. GHD in late adolescence has been defined as a peak GH level <5 microg/l. The aim of this study was to identify the likelihood of persistent GHD in late adolescence in patients with an EPP compared with those with a normally sited posterior pituitary (NPP). METHODS: In 18 patients with an EPP and 15 patients with an NPP, clinical, biochemical and radiographic data were collected. RESULTS: In the EPP vs. the NPP group, the change in peak GH levels at the end of growth was less (+0.4[95% confidence interval (CI) - 0.8 to 2.7] vs. +4.1[95%CI + 0.4 to +10.5] microg/l, P-value for ancova = 0.03, after adjustment for age and sex). Using a peak GH level of <5 microg/l as a cut-off for GHD, 66% of EPP subjects compared with 40% of NPP subjects had GHD (P = 0.3). Hundred per cent of EPP subjects had a peak GH level on retesting <10 microg/l, compared with 40% of NPP subjects (P < 0.001). CONCLUSION: It is important to document GH status at the end of growth, even if there is a structural abnormality of the hypothalamic-pituitary axis. The presence of an EPP compared to an NPP increases the likelihood of persistent GHD by 26%. As all EPP patients had a peak GH level of <10 microg/l, the cut-off for persistent GHD in late adolescence may need to be revised.

How common are rib fractures in extremely low birth weight preterm infants?

BACKGROUND: This study was prompted by incidental finding of healing rib fractures on chest radiographs of ex-preterm born infants, who were admitted to hospital with acute respiratory illnesses within a few weeks of discharge from the neonatal intensive care unit (NICU). Rib fractures in infants, particularly those situated posteriorly, are considered to be specific for non-accidental injury (NAI). METHODS: Retrospective examination of radiographs of extremely low birth weight (ELBW) infants (< or =1000 g) with a gestation range of 22 of 33 weeks, cared for at a tertiary NICU, between 1998 and 2002, and who had survived > or =4 weeks. RESULTS: Five out of 72 (7%) infants studied had radiologically apparent rib fractures. None involved posterior rib shafts. All infants with rib fractures died on the NICU. CONCLUSIONS: The possibility of NAI should be considered in ex-ELBW infants found to have rib fractures.

The anaesthetic management of children with anterior mediastinal masses.

Children with anterior mediastinal masses may experience serious complications during general anaesthesia. We retrospectively surveyed the records of children with an anterior mediastinal mass who had been admitted to our hospital over a 7 year period. The presence of pre-operative symptoms or signs, findings of any special investigations performed and the anaesthetic outcome were noted. All radiological investigations were studied and tracheal compression measured. The majority of patients presented with severe clinical signs. There was a poor relationship between clinical signs and size of tumour or tracheal compression on CT scan. Corticosteroids were used prior to diagnosis in 33% of patients, all of whom were considered high risk. A clear diagnosis was made in 95% of these patients. The overall complication rate was 20% and 5% of patients had a serious complication related to anaesthesia. Stridor was the only sign that predicted an anaesthetic complication. Peri-operative respiratory complications were confined to patients with an isolated tracheal cross-sectional area less than 30% normal or less than 70% and associated with bronchial compression.

Associations with multiple pituitary hormone deficiency in patients with an ectopic posterior pituitary gland.

INTRODUCTION: The presence of an ectopic posterior pituitary gland (EPP) on magnetic resonance imaging (MRI) is associated with hypopituitarism with one or more hormone deficiencies. We aimed to identify risk factors for having multiple pituitary hormone deficiency (MPHD) compared to isolated growth hormone deficiency (IGHD) in patients with an EPP. METHODS: In 67 patients (45 male) with an EPP on MRI, the site (hypothalamic vs. stalk) and surface area (SA) [ x (maximum diameter/2) x (maximum height/2), mm(2)] of the EPP were recorded and compared in patients with IGHD and MPHD in relation to clinical characteristics. RESULTS: In MPHD (n = 32) compared to IGHD (n = 35) patients: age of presentation was younger (1.4 [0.1-10.7]vs. 4.0 [0.1-11.3] years, P = 0.005), major incidents during pregnancy were increased (47%vs. 20%, P = 0.02) as were admissions to a neonatal intensive care unit (NICU) (60%vs. 26%, P = 0.04), whilst EPP SA was lower (12.3 [2.4-34.6]vs. 25.7 [6.9-48.2] mm(2), P < 0.001). In patients with a hypothalamic (n = 56) compared to a stalk sited EPP (n = 11): prevalence of MPHD was greater (55%vs. 9%,P = 0.05) and EPP surface area was smaller (17.3 [2.4-48.2]vs. 25.3 [11.8-38.5] mm(2), P < 0.001). In regression analysis, after adjusting for age, presence of MPHD was associated with: major incidents during pregnancy (RR 6.8 [95%CI 1.2-37.7]), hypothalamic EPP site (RR 10.9 [1.0-123.9]) and small EPP SA (RR 2.5 [1.0-5.0] for tertiles of SA). CONCLUSION: In patients with an EPP, adverse antenatal events, size (small) and position (hypothalamic) of the posterior pituitary gland on MRI were associated with MPHD. These findings suggest that adverse factors during pregnancy may be important for the development of an EPP.

The role of magnetic resonance imaging in the assessment of suspected extrinsic tracheobronchial compression due to vascular anomalies.

AIMS: To evaluate the role of magnetic resonance imaging (MRI) in the assessment of children with suspected extrinsic tracheobronchial compression due to vascular anomalies. METHODS: Retrospective case note review in a tertiary referral centre. Twenty nine children who underwent dynamic laryngotracheobronchoscopy (DLTB) and were found to have a clinical suspicion of extrinsic tracheobronchial compression were evaluated. All subsequently underwent thoracic MRI within 10 days. The findings on endoscopy were compared to those of MRI, and where performed, echocardiography, aortography, and surgery. RESULTS: There were 17 males and 12 females (mean age 5 months, range 28 weeks gestation to 60 months). The most common presenting features were stridor and cyanotic episodes. MRI showed abnormalities in 21 patients. There were five vascular rings (three double aortic arches and two right aortic arches) and 11 cases of innominate artery compression. Other vascular anomalies noted included aberrant right subclavian artery and aneurysmal left pulmonary artery. Echocardiography was generally found to be unhelpful in the diagnosis of extra-cardiac vascular abnormalities. Angiography was subsequently conducted in eight children; findings agreed with those shown on MRI. Surgery was performed on all five vascular rings, one innominate artery compression, and one aneurysmal left pulmonary artery. Surgical findings were also compatible with the preoperative MRI. CONCLUSIONS: This study shows the successful use of MRI as the initial imaging modality in endoscopically suspected extrinsic vascular compression of the upper airway. It enables accurate delineation of vascular anomalies and, unlike aortography, is non-invasive and does not require the use of contrast media.

Endocrine status in patients with optic nerve hypoplasia: relationship to midline central nervous system abnormalities and appearance of the hypothalamic-pituitary axis on magnetic resonance imaging.

We here: 1) describe the phenotypic spectrum, including magnetic resonance imaging (MRI) appearances of the pituitary stalk and anterior and posterior pituitary [H-P (hypothalamic-pituitary) axis], in children with optic nerve hypoplasia (ONH) with or without an abnormal septum pellucidum (SP); and 2) define endocrine dysfunction according to the MRI findings. Medical records of 55 children with ONH who had been assessed by ophthalmology and endocrine services were reviewed. All had MRI of the brain and H-P axis. Forty-nine percent of the ONH patients had an abnormal SP on MRI, and 64% had a H-P axis abnormality. Twenty-seven patients (49%) had endocrine dysfunction, and 23 of these had H-P axis abnormality. The frequency of endocrinopathy was higher in patients with an abnormal SP (56%) than a normal SP (39%). Patients were divided into four groups based on SP and H-P axis appearance: 1) both normal; 2) abnormal SP and normal H-P axis; 3) normal SP and abnormal H-P axis; and 4) both abnormal. The frequency of multiple pituitary hormone deficiency was highest (56%) in group 4, lower (35%) in group 3, and even lower (22%) in group 2. Precocious puberty was most common in group 2. None of the patients in group 1 had endocrine dysfunction. Thus, SP and H-P axis appearances on MRI can be used to predict the likely spectrum of endocrinopathy.

Iodixanol in paediatric gastrointestinal imaging: safety and efficacy comparison with iohexol.

Iodixanol (Visipaque) is a dimeric, non-ionic iodinated contrast medium that is isotonic with blood at all clinically relevant concentrations. Iodixanol was compared in a randomized, double blind, parallel group, phase III multicentre trial with a monomeric, non-ionic contrast medium, iohexol (Omnipaque), at two concentrations assessing safety, tolerability and radiographic efficacy during contrast enhanced gastrointestinal radiography examinations of children. 154 children entered the trial; 152 formed the safety population and 147 the efficacy population. All examinations were performed following standard departmental practice. Children were assigned into either a high or low concentration group (iodixanol, 150 mgI ml(-1) and 320 mgI ml(-1) vs iohexol, 140 mgI ml(-1) and 300 mgI ml(-1)). The primary outcome measure for efficacy was the overall quality of visualization, which was assessed using a 100 mm visual analogue scale (VAS). The secondary efficacy variables assessed were quality of contrast opacification, mucosal coating and overall quality of diagnostic information. Safety evaluation involved patient follow-up for at least 48 h. Taste acceptance was also assessed. There was no statistically significant difference between the two contrast media with regard to the primary and secondary efficacy variables assessed, although higher ratings were observed for iodixanol. The 100 mm VAS score overall was 86 mm for iodixanol and 82 mm for iohexol (95% confidence interval -2.56, 10.42). The frequency of adverse events was lower for patients receiving iodixanol. Adverse events, mainly diarrhoea, occurred in 12 patients (16.2%) in the iodixanol group and 28 patients (35.9%) in the iohexol group. This reached statistical significance (p=0.006). Overall, iodixanol is well suited for examinations of the gastrointestinal tract, giving good efficacy results and fewer adverse events than iohexol.

Magnetic resonance imaging in the diagnosis and management of choroid plexus carcinoma in children.

BACKGROUND: Choroid plexus carcinoma (CPC) is a rare tumour occurring in childhood. The MRI features are not well described. OBJECTIVE: To characterise the MRI features of CPC in children and to describe the role of MRI in post-surgical management. MATERIALS AND METHODS: The pre- and post-operative MRI examinations of five children with histologically proven CPC treated at this hospital were reviewed. RESULTS: The tumour was supratentorial in two patients and infratentorial in three patients. Pre-operative MRI showed heterogeneous enhancing tumours with irregular margins, parenchymal invasion and surrounding oedema. Cystic change within the tumour was present in all patients. Curvilinear signal voids were seen in two patients and punctate signal voids in one. All patients had hydrocephalus. In one patient a fourth-ventricular metastasis was present at diagnosis. In all cases, surgical resection was incomplete. Follow-up found long-term survival in one patient who had been treated with chemotherapy and further surgery. CONCLUSION: The MRI characteristics of CPC are nonspecific, but intraventricular location with tumour heterogeneity, parenchymal invasion and oedema may be useful features in diagnosis. MRI is valuable in the initial diagnosis, surgical planning and follow-up of children with these rare tumours.

Imaging in epilepsy: a paediatric perspective.

Assessment of a child with epilepsy involves a number of key stages, the most crucial being clinical evaluation where the presence of seizure activity and seizure type is identified. Subsequent imaging is not required in all children. In those selected for further investigation, imaging techniques are broadly divided into structural and functional studies. MRI currently provides the best structural data, with nuclear medicine and specialized MR techniques giving supportive functional information. CT now has a much diminished role. This review highlights the role of different imaging modalities in the investigation of childhood epilepsy, as well as some of the practicalities of imaging children, and areas where recent advances have been made. It is hoped that the overview and information provided will help both the specialist and the general radiologist make informed decisions regarding how to best image a child with epilepsy.

Bilateral subdural effusions related to disease activity in familial hemophagocytic lymphohistiocytosis in an 8-month-old infant.

An 8-month-old girl had classic features of hemophagocytic lymphohistiocytosis (HLH). A presumptive diagnosis of familial hemophagocytic lymphohistiocytosis was made on the basis of her age and the presence of parental consanguinity. In view of abnormal neurologic findings at presentation, a magnetic resonance imaging scan was performed and showed bilateral proteinaceous subdural effusions. These resolved within 1 week of commencement of chemotherapy for the primary condition. These subdural effusions were the only objective documentations of central nervous system involvement, along with an increased cerebrospinal fluid protein level. We also report other radiologic findings of HLH, which are of use in strengthening this diagnosis in individuals in whom the diagnosis is strongly suspected.

Magnetic resonance imaging of the hypothalamic-pituitary axis in the diagnosis of growth hormone deficiency.

In order to investigate the relationship between pituitary appearance and the diagnosis of growth hormone deficiency (GHD), we have assessed magnetic resonance imaging (MRI) scans and GH status during provocation tests in 110 patients (78 males; median age 9.8, range 0.1-20 yr), evaluated for possible GH disorders. On the basis of pituitary function tests, patients were divided into GH deficient (GH peak < 15 mIU/l [5.8 ng/ml]) (n = 82) or GH sufficient (GH peak > 15 mIU/l) (n = 28). The former were further divided into those with multiple hormone deficits (MPHD) (n = 19) or isolated GHD - severe IGHD (peak GH < 8 mIU/l [3.1 ng/ml]) or partial IGHD (8-15 mIU/l). The appearance of the hypothalamic-pituitary (H-P) axis was classified as: (1) normal, (2) isolated hypoplastic stalk (HPS), (3) isolated hypoplastic anterior lobe (HPAL) (PHT SDS < -2.0), (4) HPS + HPAL or (5) ectopic posterior lobe (EPL). The last two were considered severe abnormalities. PHT SDS (mean +/- SD -2.0 +/- 2.2) was correlated to log peak GH levels in the whole group (r = 0.45; p < 0.0001) and in the GHD group (r = 0.39; p < 0.0001). Sixty-five out of 82 in the GHD group had a H-P axis abnormality (45 severe abnormalities), while 13 out of the 28 patients in the GH sufficient group also had an abnormality (3 severe, but none with an EPL). All patients with MPHD had a MRI abnormality, most commonly an EPL (79%). Thus the presence of any MRI abnormality as a marker for GHD would generate a sensitivity of 79%, but a specificity of only 54%, indicating that this could not be used to confirm GHD. However, the presence of either an EPL or HPS + HPAL on MRI is highly specific (100% and 89% respectively) and predictive of GHD (positive predictive value 100% and 79% respectively), indicating that these abnormalities provide confirmation of the diagnosis. We recommend that if clinical, auxological and biochemical data indicate a diagnosis of GHD, then a MRI scan should be undertaken to define the pituitary anatomy and to help confirm the diagnosis.

Removal of orthopedic implants in children: morbidity and postoperative radiologic changes.

One hundred twenty-one procedures for the removal of metalwork performed on 110 children aged 1-15 years is reported, with a focus on postoperative morbidity and radiographic skeletal changes. The removals were for a variety of acute and chronic pediatric orthopedic conditions. The level of postoperative morbidity was lower than in adult study groups with only one refracture (0.9%). Only four removals were considered to be difficult. All patients had a postoperative radiograph taken. The skeletal response to the fixation device was assessed by measuring the degree of cortical assimilation of the implant. Dynamic compression plating was compared with third tubular fixation. Overall cortical indentation was 7.3% in the third tubular group and 41.6% in the dynamic compression plating group; similar results were found in forearm fracture and hip osteotomy subgroups (P < 0.01, Wilcoxon unpaired test). The degree of indentation was related to the length of time for which the plate was left in situ. It is postulated that plates with high stress-rising characteristics are incorporated with growth and should both be removed early and have strictly limited indications for their use.

Isolated H-type recto-vaginal fistula associated with a vulval abscess.

Recto-vaginal fistula is well known to occur in association with imperforate anus. We describe the case of an isolated "H-type" recto-vaginal fistula with no other anorectal abnormalities. The patient presented at 2 months of age with a vulval abscess and passing faeces per vaginum. Unilateral renal agenesis was also seen in this patient. We are unaware of any previous reports in the English-language literature of this isolated abnormality.

Antenatal and neonatal renal vein thrombosis: new ultrasonic features with high frequency transducers.

The ultrasonic appearances of two infants with renal vein thrombosis (RVT) are described. One infant presented in the neonatal period and one antenatally. Consistent with previous reports, one or both kidneys were enlarged, with a generalised increase in echogenicity and vascular or perivascular streaking compatible with interlobular and arcuate vessel occlusion. Using high frequency transducers (7. 0-10 MHz), we identified new features during the course of the disease. The apex of the renal papilla became hypo-echoic and there was a ring of reduced echogenicity around the affected pyramids 1-2 weeks after the acute phase. These features correlate with the known pathophysiological course of RVT, but have not been previously described using ultrasound. The features are illustrated and the mechanism is discussed.

Ultrasound in children with osteomyelitis.

Ultrasound (US) is a proven method of identifying subperiosteal abscess formation in osteomyelitis, but its precise role in the management of children with the condition is contentious. We reviewed nine children in whom US was used in the management of long bone osteomyelitis, including ribs. US was helpful in confirming the presence of a subperiosteal abscess in those children with an appropriate history and localizing signs. In these circumstances a bone scan is unnecessary. Problems were encountered when US failed to identify a subperiosteal abscess, because of the early stage of the disease process, and in multifocal abnormalities. In these circumstances a bone scan should still be performed.

Intrathoracic rib.

The intrathoracic rib is a rare anomaly. Despite this, it has distinctive radiological features which should enable a confident diagnosis to be made from the chest radiograph alone. Its importance lies in recognising it as a benign lesion and limiting further investigation appropriately. We present an 11-year-old girl with an intrathoracic rib found incidentally on a chest radiograph.