Neuroradiologic findings in children with mitochondrial disorder: correlation with mitochondrial respiratory chain defects

Mitochondrial disorders are a heterogeneous group of disorders affecting energy metabolism that can present at any age with a wide variety of clinical symptoms. We investigated brain magnetic resonance (MR) findings in 40 children with defects of the mitochondrial respiratory chain (MRC) complex and correlated them with the type of MRC defects. Enrolled were 40 children with MRC defects in biochemical enzyme assay of the muscle specimen. Twenty-one children were found to have classical syndromes of mitochondrial disorders and 19 children presented nonspecific mitochondrial encephalomyopathies. Their brain MR imaging findings were retrospectively reviewed and correlated with the biochemical defect in the MRC complex. Children with MRC defects showed various neuroradiologic features on brain MR imaging that resulted from a complex genetic background and a heterogeneous phenotype. Rapid progression of atrophy involving all structures of the brain with variable involvement of deep gray and white matter are the most frequent MR findings in children with MRC defects in both classical syndromes of mitochondrial disorder and nonspecific mitochondrial encephalomyopathies. The type of biochemical defect in the MRC complex enzyme did not correlate with brain MR findings in child patients.     

Neuroradiologic findings in fucosidosis,a rare lysosomal storage disease.

Fucosidosis is a rare lysosomal storage disorder with the clinical features of mental retardation, cardiomegaly, dysostosis multiplex, progressive neurologic deterioration, and early death. The neuroradiologic findings in two patients are reported, and include abnormalities within the globus pallidus (both patients) and periventricular white matter (one patient).     

Neuroradiologic findings in Marinesco-Sjögren syndrome.

PURPOSEOur purpose was to determine the neuroradiologic findings of Marinesco-Sjögren syndrome on plain skull radiographs, CT, and MR images.METHODSEight patients with proved Marinesco-Sjögren syndrome (age range, 4 to 56 years) had a total of nine CT scans, seven MR imaging studies, and two plain radiographic examinations of the skull. The findings were reviewed retrospectively, with particular attention to the size of the posterior fossa and cerebellum.RESULTSAll patients had hypoplastic cerebellar hemispheres and a hypoplastic vermis in a small posterior fossa. One patient had a midline posterior fossa cyst and another had agenesis of the corpus callosum.CONCLUSIONHypoplasia of the cerebellar hemispheres and the vermis and a small posterior fossa are the most prominent neuroradiologic findings in Marinesco-Sjögren syndrome.     

Neuroradiologic findings of hypothalamic hamartoma with emphasis on computed tomography

Hypothalamic hamartoma is a relatively rare congenital malformation. Five new cases and 31 cases in the literature were evaluated in regard to neuroradiologic findings with emphasis on computed tomography. Five important computed tomography findings were observed: oval-shaped, isodense suprasellar mass; clear demarcation; no enhancement effect; absence of cystic component or calcification; and no effacement of the third ventricle. Clinical features, mechanism of the precocious puberty, and differential diagnosis are also discussed.     

Neuroradiologic findings in AIDS: a review of 200 cases

The radiologic studies of 200 consecutive AIDS patients with neurologic symptoms were evaluated to determine their diagnostic specificity and prognostic value. Of 81 patients with initially normal CT scans, four (5%) later developed progressive neurologic illness. Of 75 patients with CT evidence of diffuse cerebral atrophy, 12 (16%) later developed CT abnormalities or had postmortem CNS disease. CT scans showed mass lesions initially in 44 patients and later in an additional seven patients. Although toxoplasma gondii infection was the most frequent cause of these lesions, the CT characteristics of cerebral toxoplasmosis are too nonspecific to warrant diagnosis without biopsy. Preliminary evidence suggests that MRI may be more sensitive than CT in detecting intracranial disease in patients with AIDS.     

Neuroradiologic findings in leptomeningeal carcinomatosis: the value interest of gadolinium-enhanced MRI

Summary Four patients with leptomeningeal metastases documented by neuroradiological examinations are reported. All had central nervous system or systemic neoplasms and showed clinical signs of carcinomatous meningitis. Gadolinium-enhanced MRI (Gd-MRI) disclosed for each patient pathological foci, allowing delineation of the extent of meningeal disease. Although non-specific, these findings, combined with the clinical context and CSF analysis, may lead to a rapid diagnosis and treatment of carcinomatous meningitis, even when malignant cells are not detected in the cerebrospinal fluid.     

Metabolic and destructive brain disorders in children: findings with localized proton MR spectroscopy

The diagnostic potential of volume-selective proton magnetic resonance (MR) spectroscopy in vivo was evaluated in 20 children and young adults with various neurodegenerative brain disorders. All patients were examined with MR spectroscopy in conjunction with MR imaging of the brain on a whole-body imager at 1.5 T. Comparison of spectra in our patients with those of children with normal myelination (prominent signals from N-acetylaspartate [NAA], creatine/phosphocreatine, and choline) revealed a marked decrease of NAA in 12 of 17 patients with focal or generalized demyelination. In patients with Canavan disease, NAA signal intensity was markedly increased, but no choline signal was found. Increased signal intensity from lactate occurred in patients with Leigh disease, neuroaxonal dystrophy, Schilder disease, and Cockayne disease, which indicated a disturbed energy metabolism in the examined region. These results demonstrate that proton MR spectroscopy can be applied in a clinical environment to facilitate diagnosis of hereditary and acquired brain disorders in children.     

Diagnostic value of MRS-quantified brain tissue lactate level in identifying children with mitochondrial disorders

Objectives

Magnetic resonance spectroscopy (MRS) of children with or without neurometabolic disease is used for the first time for quantitative assessment of brain tissue lactate signals, to elaborate on previous suggestions of MRS-detected lactate as a marker of mitochondrial disease.

Methods

Multivoxel MRS of a transverse plane of brain tissue cranial to the ventricles was performed in 88 children suspected of having neurometabolic disease, divided into ‘definite’ (n?=?17, ≥1 major criteria), ‘probable’ (n?=?10, ≥2 minor criteria), ‘possible’ (n?=?17, 1 minor criterion) and ‘unlikely’ mitochondrial disease (n?=?44, none of the criteria). Lactate levels, expressed in standardized arbitrary units or relative to creatine, were derived from summed signals from all voxels. Ten ‘unlikely’ children with a normal neurological exam served as the MRS reference subgroup. For 61 of 88 children, CSF lactate values were obtained.

Results

MRS lactate level (>12 arbitrary units) and the lactate-to-creatine ratio (L/Cr >0.22) differed significantly between the definite and the unlikely group (p?=?0.015 and p?=?0.001, respectively). MRS L/Cr also differentiated between the probable and the MRS reference subgroup (p?=?0.03). No significant group differences were found for CSF lactate.

Conclusion

MRS-quantified brain tissue lactate levels can serve as diagnostic marker for identifying mitochondrial disease in children.

Key points

? MRS-detected brain tissue lactate levels can be quantified.? MRS lactate and lactate/Cr are increased in children with mitochondrial disease.? CSF lactate is less suitable as marker of mitochondrial disease.

     

Neuroradiologic aspects of Chester-Erdheim disease.

In three cases of histologically proved Chester-Erdheim disease there was a large anterior epidural lesion from C-3 to L-2 in one patient; dural masses and orbital infiltration in a second patient; and dural, choroid plexus, retroorbital, and hypophyseal lesions in a third patient. Diabetes insipidus, exophthalmia, long bone lesions, and retroperitoneal infiltration were present.     

CT and MR imaging findings in adults with cerebellar medulloblastoma: comparison with findings in children.

The goal of this study was to determine if certain imaging features suggest the diagnosis of cerebellar medulloblastoma in adults and to determine how often the classic CT appearance seen in children is present in adults. The study included 28 adult patients with proved cerebellar medulloblastoma. The tumor was located in the cerebellar vermis in 14 patients and in a cerebellar hemisphere in 14 patients. Thirteen patients had unenhanced CT of the brain, all patients had contrast-enhanced CT, and eight patients had unenhanced MR imaging. The imaging features in adults were compared with those in children, as described in the literature. In our adult patients, all tumors were hyperdense compared with gray matter on unenhanced CT and showed a slight to moderate increase in density after injection of contrast medium. Thirteen lesions had well-defined margins, and 15 had poorly defined margins. Low-density areas consistent with cystic and necrotic degeneration were detected in 23 (82%) of the 28 tumors. By comparison, in children, medulloblastoma usually originates in the vermis. As in adults, the mass is hyperdense on unenhanced CT, but enhances markedly and homogeneously after injection of contrast medium. Usually no evidence of cyst formation or necrosis is seen, and the tumor margins are well defined. This classic CT appearance of medulloblastoma in children was identified in only three (11%) of the 28 adult patients. Medulloblastoma has a variable MR appearance in both children and adults. On T2-weighted images, lesions are hypo-, iso-, or hyperintense compared with normal gray matter. The CT findings of medulloblastoma in adults usually differ from those of medulloblastoma in children. The tumor has a variable and nonspecific appearance in adults and should always be considered in the differential diagnosis of a mass in the posterior fossa.     

Neuroradiologic abnormalities in Marchiafava-Bignami disease of benign evolution.

Marchiafava-Bignami disease has been recognized since 1903, but only recently has it become possible to achieve a probable diagnosis before death occurs. Imaging of the central nervous system with MR and CT have contributed significantly to such a diagnosis. Two cases of the disease are reported in patients, aged 33 and 59 years, with benign evolution of neurologic symptoms the diagnosis was confirmed by neurologic imaging with MR and CT and both were studied with evoked responses. Reversibility of the disease and possible prognostic indicators in these and other patients reported in the literature are discussed. The important role that diagnostic procedures, especially MR imaging, play in the management of this disease is emphasized.     

Radiographic findings in ovarian teratomas in children.

Twenty-one infants and children with ovarian teratomas are reported. Calcification or ossification occurred in 68%, a higher figure than quoted in prior series. Teeth were recognized in 29% of these. A lucent fat-containing mass was appreciated in only two patients. In younger children the tumor was more frequently abdominal rather than pelvic. In two patients the tumor was malignant. A patient with an amputated freely mobile teratoma is reported in detail and the differential diagnosis of mobile abdominal calcifications discussed.     

Cerebral vascular autoregulatory dysfunction. Neuroradiologic aspects]

PURPOSE: We report the neuroimaging findings in a group of systemic disorders with a common pathophysiological pattern of derangements in cerebral vascular autoregulatory mechanism producting potentially reversible brain lesions. MATERIAL AND METHODS: We reviewed the brain CT and MR examinations of 14 patients with clinical diagnosis of vasculopathy not related to atherosclerosis or cardiogenic embolism. The patients were admitted at the onset of neurologic deficit and were affected with one of the following systemic disorders: thrombotic thrombocytopenic purpura (TTP, 6 cases), uremic encephalopathy (4 cases), eclampsia (2 cases), 1 chronic renal failure from systemic lupus erythematosus and 1 cyclosporin neurotoxicity. All patients underwent neuroimaging follow-up within 7-20 days of the onset of neurologic deficit and the start of anti-edema therapy. RESULTS: CT and MR findings were characterized by cortical-subcortical or deep brain lesions related to edema. Ten patients presented bilateral lesions, which were symmetric in 4 cases. Edema resolution was demonstrated on follow-up examinations after therapy in 4 patients (2 with eclampsia, 1 with TTP and 1 with uremic encephalopathy). The lesions showed no signs of regression in 10 patients. CONCLUSIONS: Brain lesions with a common pathogenesis from derangements in vascular autoregulatory mechanism--i.e., not due to atherosclerosis or cardiogenic embolism--should be properly and promptly recognized because they can be reversible and readily treatable.     

Ultrasound findings in children with cystic fibrosis

The results of a prospective study using ultrasound to assess abdominal complications in 76 children with proven cystic fibrosis are reported. Fifty-six patients (74%) had normal liver ultrasound scans. The most striking abnormality was an irregular, inferior edge to the liver occurring in 85% of abnormal liver scans and in 70% there was corresponding clinical and biochemical evidence of abnormal liver function. This finding has been only briefly mentioned before. Increased reflectivity in abnormalities of the pancreas and gallbladder is also described.     

Posttraumatic shock in children: CT findings associated with hemodynamic instability.

Twenty-seven of 1,018 children evaluated with contrast material-enhanced computed tomography (CT) after blunt trauma demonstrated a characteristic hypoperfusion complex. This complex was usually seen in young children (median age, 2 years). CT findings in all 27 patients included a dilated, fluid-filled bowel and abnormally intense enhancement of the bowel wall, mesentery, kidneys, aorta, and inferior vena cava. Twenty-four percent of all children with a Trauma Score of 10 or less and 20% with a Glasgow Coma Score of 6 or less had the hypoperfusion complex. All 27 patients had a normal blood pressure immediately before CT, but five (19%) became hypotensive within 10 minutes of intravenous contrast material administration. Twenty-three children (85%) died. Of 16 children who survived 24 hours, four (25%) developed renal insufficiency. The intense multiorgan enhancement pattern seen in the hypoperfusion complex indicates tenuous hemodynamic stability. Recognition that the constellation of CT findings is due to hypovolemic shock and not to injured viscera helps avoid unnecessary laparotomy.