MR imaging of the ischiopubic synchondrosis

The ischiopubic synchondrosis (IPS) is a temporary joint, occurring in childhood prior to fusion of the ischial and pubic bones. On conventional radiographs this tumor-like appearance is a well known normal anatomic variant, however, there are no reports in the literature of the appearance of IPS on MRI. Therefore the purpose of this study was to evaluate typical magnetic resonance features of the IPS. All pelvic MRIs from 1/1992 to 4/1998 of children ranging in age from 4 to 16 years, who were scanned for reasons other than bone disorders, were retrospectively investigated. Twenty-eight children were included and the morphologic appearance of IPS on MRI was evaluated. Seventeen (61%) of these 28 children had the following findings of IPS on MRI. Listed in order of frequency we found signal alteration of the ischiopubic fusion zone [hyperintense on T(2) with fat-saturation (89%) or STIR (74%), hypointense on T(1) (71%)], fibrous "bridging" (68%) [hypointense band on all sequences in perpendicular orientation to the axis of the inferior pubic ramus], fusiform swelling (68%), signal alteration of the adjacent soft tissue (57%) and irregular margins (56%). In 10 children contrast enhanced scans were available for evaluation, showing contrast enhancement of the bone marrow in 83.3% and of the adjacent soft tissue in 66.7%. Fusiform swelling of the ischiopubic fusion zone, signal alteration and contrast enhancement of both the bone marrow and the adjacent soft-tissue are characteristic features of the IPS on MRI, which may be due to mechanical stress at this temporary joint. These features are nonspecific and may resemble tumor, infection or trauma. Fibrous "bridging" was the only finding on MRI, which has not been described for any other entity and thus, it seems to be a characteristic MRI-feature.

Successful conservative treatment of severe renal candidosis with fungus balls

Partial fungal obstruction of the renal collecting system is an unusual finding among infants that poses specific management problems. We report a patient with sepsis and fungal infection of the kidneys post surgery who presented with bilateral fungus balls and was successfully managed by conservative measures. Sonography is the imaging technique of choice in the diagnosis and follow-up of such patients. The need for prompt diagnosis in high-risk patients and the role of sonography are discussed.

[Radiologic staging of thoracic and abdominal tumors in childhood]

Thoracoabdominal tumors in childhood can arise from all organs and affect children from the neonate to the adolescent. Better prognosis of childhood tumors, due to better biological understanding and improvement of chemotherapy, require sufficient radiological staging. Sufficiency in radiological staging needs modern cross-sectional techniques with high resolution, good availability and lower radiation dose. In general computed tomography (CT) is being used for radiological staging; increasingly MR imaging is being used because of multiplanar imaging techniques. Replacement of invasive techniques such as myelography and lymphography and modern cross-sectional techniques create painless staging conditions. Nevertheless, scintigraphy will always be a major examination technique, especially for evaluation of metastases and postoperative control examinations. The most common thoracoabdominal tumors in childhood and their staging are described.

Magnetic resonance imaging in hemophilic children: value of gradient echo and contrast-enhanced imaging

The purpose of this study was to determine the value of Gradient Echo imaging for the evaluation of cartilage (3D fatsat) and blood products (2D Hemoflash), and the use of contrast enhanced SE imaging for the evaluation of synovial changes, in comparison to the clinical evaluation of children with hemophilia A. We investigated 21 joints in 16 patients with evidence of hemophilia A (mean age 11.3+/-2.1 years). In all patients, clinical examination, plain film radiographs, and MR evaluation were performed magnetic resonance imaging (MRI) was performed by using sagittal T1 SE and T2 SE images, as well as 3D fatsat GE and 2D GE images. Axial and sagittal T1 weighted SE images were obtained before and after contrast application. Findings from the clinical examination and MR imaging, regarding the evaluation of blood, synovia, and cartilage were compared. Clinical examination revealed evidence of a bleeding episode in 12 joints (57.1%), whereas MRI revealed evidence of blood or blood products in 15 joints (71.4%). Clinical investigations, including bleeding scores, pain scores, and physical examination scores did not correlate with MR findings. Due to the MR findings in 6 of 16 patients, therapeutic management was changed from on demand to prophylactic therapy. MR imaging with gradient echo and contrast-enhanced sequences is more sensitive than clinical examination for the detection of blood products in children with hemophilia. Its ability to demonstrate potentially early stages of cartilage or synovial alterations might assist in therapy planning. Clinical scores might underestimate effects of hemophilia.

[An adult patient with phenylketonuria before and one year after reinstitution of diet therapy]

BACKGROUND

In phenylketonuria (PKU) a phenylalanine restricted diet during the first years of life can prevent the development of severe cognitive damage.

OBJECTIVE

Could neuropsychological or neurological changes occur in a 20-year-old patient with PKU (diagnosed early and treated until the age of 8 years) after 12 years of normal nutrition and if so, can these changes be counteracted by reinstitution of a low phenylalanine diet?

METHODS

Psychological (intelligence, attention), neurophysiological (evoked potentials) and neuroradiological examination (magnetic resonance tomography [MRT] of the brain) were performed before and after one year of treatment with a diet low in phenylalanine.

RESULTS

During the reinstitution of dietary therapy we observed significant improvements in attentiveness (percentage increase of 30), whereas intelligence subtests remained stable, a reduction in hyperreflexia, shortening of the latencies of the evoked potentials and a decrease in periventricular pathological signal alterations as evaluated by MRT.

CONCLUSIONS

The reintroduction of a diet low in phenylalanine improved psychological and neurological symptoms in this PKU patient. We recommend a constant low-phenylalanine diet throughout life in patients with PKU.

Stroke-like encephalopathy in an infant with 3-hydroxy-3-methylglutaryl-coenzyme A lyase deficiency

A 2.5-year-old boy presented with acute metabolic decompensation in whom 3-hydroxy-3-methyl-glutaryl-coenzyme A (HMG-CoA) lyase deficiency was diagnosed. Four days after metabolic decompensation, a stroke-like encephalopathy with tonic clonic convulsion of the left arm and leg and coma developed. Brain oedema and subsequent demarcation and atrophy were observed mainly within the supply areas of the right anterior and middle cerebral artery and to a lesser extent in various sites within the right hemisphere. Residual neurological deficits included spastic paresis of the left arm and leg. and left supranuclear facial palsy and aphasia, indicating bilateral diffuse brain affection.

CONCLUSION

In the presented patient with HMG-CoA lyase deficiency, stroke-like encephalopathy occurred days after metabolic decompensation indicating ongoing (intracerebral) metabolic derangement. Monitoring of the intracerebral accumulation of toxic metabolites by magnetic resonance spectroscopy and of cerebral haemodynamics might be useful for a better understanding of the pathogenetic mechanisms of stroke-like encephalopathy and to identify patients at risk.

Kinking and stenosis of the carotid artery associated with homolateral ischaemic brain infarction in a patient treated with cyclosporin A

We present a 3-year-old patient with stenotic kinking of the left internal carotid artery (ICA) who developed an ischaemic infarction of the left brain hemisphere followed by severe neurological sequelae after a prolonged generalized seizure. At time of the seizure the boy was in biological remission of a nephrotic syndrome and received prednisolone and cyclosporin A (CsA) treatment. The haemodynamic consequences of inborn kinking of the ICA is discussed controversely in the literature. The presented case shows that stenotic kinking of the ICA may significantly impair the blood flow towards the homolateral hemisphere and therefore may result in an ischaemic infarction. The influence of CsA on seizure activity is discussed.

CONCLUSION

This case provides clinical and radiological evidence supporting an association between stenotic kinking of the carotid artery and homolateral hemispheric brain infarction.

Primary hypothyroidism, central diabetes insipidus and growth hormone deficiency in multisystem Langerhans cell histiocytosis: a case report

We report on a girl with central diabetes insipidus, growth hormone deficiency and bone lesions in multisystem Langerhans cell histiocytosis. Thickening of the pituitary stalk was detected by magnetic resonance imaging, which progressed over the course of the disease. During the observation period she developed primary hypothyroidism, which might be due to the extremely rare involvement of the thyroid gland in this disease. The girl underwent chemotherapy, which led to a regression of the Langerhans cell histiocytosis-lesion, but the hormone deficiencies persisted and substitution had to be continued. Langerhans cell histiocytosis should be included in the differential diagnosis in cases with pituitary stalk thickening and additional hypothalamic/pituitary hormone deficiencies, and in cases of acquired primary hypothyroidism, with or without enlargement of the thyroid gland and ultrasound findings similar to thyroiditis.

[Cholestasis syndrome in newborn infants: value of gallbladder ultrasound]

PURPOSE

Evaluation of sonography in the assessment of changes of the biliary system of newborn infants receiving total parenteral nutrition.

PATIENTS AND METHODS

In 20 premature infants on mechanical ventilation, the influence of two different amino acid solutions (Vaminolac, Paedamin) in the development of neonatal cholestasis was analysed. The patients were randomised in two groups. Group 1 (n = 11) received Paedamin, group 2 (n = 9) received Vaminolac.

RESULTS

There was no statistically significant influence of the amino acid solution on the development of cholestasis. However, the majority of the children with cholestasis (8 of 11) presented with sepsis.

CONCLUSION

Bacterial infections seem to be closely related to the development of cholestasis. Sludge formation within the bile ducts represents a sensitive sonographic parameter for the diagnosis and follow-up of cholestasis secondary to total parenteral nutrition.

Diagnosis of X-recessive Kallmann syndrome in early infancy. Evidence of hypoplastic rhinencephalon

A 3-month-old infant presented with hypogonadism, a small penis and bilateral cryptorchidism. He showed an insufficient response of luteotropic hormone (LH) and follicle stimulating hormone (FSH) to luteotropic hormone releasing hormone (LHRH) and of testosterone to human chorionic gonadotropin. The maternal uncle had hypogonadism and anosmia and also showed an impaired LH and FSH response to LHRH. MRI examination showed hypoplasia of the rhinencephalon in both cases. These findings in the son and brother of the clinically unaffected mother suggest X-linked recessive inheritance.