Massimo Gallucci

Central diabetes insipidus in children and young adults

BACKGROUND Central diabetes insipidus is rare in children and young adults, and up to 50 percent of cases are idiopathic. The clinical presentation and the long-term course of this disorder are largely undefined. METHODS We studied all 79 patients with central diabetes insipidus who were seen at four pediatric endocrinology units between 1970 and 1996. There were 37 male and 42 female patients whose median age at diagnosis was 7.0 years (range, 0.1 to 24.8). All patients underwent magnetic resonance imaging (MRI) and periodic studies of anterior pituitary function. The median duration of follow-up was 7.6 years (range, 1.6 to 26.2). RESULTS The causes of the central diabetes insipidus were Langerhans-cell histiocytosis in 12 patients, an intracranial tumor in 18 patients, a skull fracture in 2 patients, and autoimmune polyendocrinopathy in 1 patient; 5 patients had familial disease. The cause was considered to be idiopathic in 41 patients (52 percent). In 74 patients (94 percent) the posterior pituitary was not hyperintense on the first MRI scan obtained, and 29 patients (37 percent) had thickening of the pituitary stalk. Eighteen patients had changes in the thickness of the pituitary stalk over time, ranging from normalization (six patients) or a decrease in thickness (one patient) to further thickening (seven patients) or thickening of a previously normal stalk (four patients). Anterior pituitary hormone deficiencies, primarily growth hormone deficiency, were documented in 48 patients (61 percent) a median of 0.6 year (range, 0.1 to 18.0) after the onset of central diabetes insipidus. CONCLUSIONS Most children and young adults with acquired central diabetes insipidus have abnormal findings on MRI scans of the head, which may change over time, and at least half have anterior pituitary hormone deficiencies during follow-up.

Magnetic resonance imaging findings of amygdala- anterior hippocampus shrinkage in male patients with schizophrenia

Recent magnetic resonance imaging (MRI) studies found abnormalities of medial temporal lobe and basal ganglia structures. We used an inversion recovery (IR) protocol with the assistance of the Talairach atlas to identify neuroanatomical regions of interest in 19 male schizophrenic patients and 14 matched control subjects. The patient group showed smaller amygdala-hippocampus volume as compared with normal control subjects. This finding was more pronounced for the left side, although no diagnosis X side interaction was present. Third ventricle volume was also enlarged in schizophrenic patients. Trends toward an overall reduction of basal ganglia (striatum and lenticular nucleus) and limbic structures and toward an increase in ventricle-brain ratio were also seen. The study confirms previous evidence of mesial temporal lobe shrinkage, more evident on the left side in a group of relapsing noninstitutionalized male schizophrenic patients.

Planum temporale in schizophrenia: a magnetic resonance study

Magnetic resonance imaging (MRI) scans were used to examine the size and asymmetry of the planum temporale (PT) in 20 schizophrenic patients and 12 strictly matched healthy volunteers. PT lengths from coronal sections were measured and then summed to obtain an estimate of their areas. Schizophrenics showed the lack of the physiological PT area asymmetry evidenced in the control sample and a statistically significant diagnosis by side interaction was observed (F = 4.96; p less than 0.05). The study of PT asymmetry could permit us to better analyse the role of laterality in the pathophysiology of schizophrenia.

Reversible focal splenial lesions

Reversible focal lesions in the splenium of the corpus callosum (SCC) have recently been reported.They are circumscribed and located in the median aspect of the SCC. On MRI, they are hyperintense on T2-W and iso-hypointense on T1-W sequences, with no contrast enhancement. On DWI, SCC lesions are hyperintense with low ADC values, reflecting restricted diffusion due to cytotoxic edema. The common element is the disappearance of imaging abnormalities with time, including normalization of DWI. Clinical improvement is often reported. The most established and frequent causes of reversible focal lesions of the SCC are viral encephalitis, antiepileptic drug toxicity/withdrawal and hypoglycemic encephalopathy. Many other causes have been reported, including traumatic axonal injury. The similar clinical and imaging features suggest a common mechanism induced by different pathological events leading to the same results. Edema and diffusion restriction in focal reversible lesions of the SCC have been attributed to excitotoxic mechanisms that can result from different mechanisms; no unifying relationship has been found to explain all the pathologies associated with SCC lesions. In our opinion, the similar imaging, clinical and prognostic aspects of these lesions depend on a high vulnerability of the SCC to excitotoxic edema and are less dependent on the underlying pathology. In this review, the relevant literature concerning reversible focal lesions in the SCC is analyzed and hypotheses about their pathogenesis are proposed.

Hemispheric asymmetries and schizophrenia: A preliminary magnetic resonance imaging study

A magnetic resonance imaging (MRI) study of 20 chronic schizophrenic outpatients (5 women and 15 men) and 20 healthy volunteers, individually matched for age and sex, was conducted. Schizophrenics showed a statistically significant lateral ventricular enlargement and smaller corpus callosum: brain ratio than controls. There were no statistically significant differences in hemispheric measurements between groups. Nevertheless, we found a wider right frontal width versus the left in the patient group but not in the control group, and more frontal protuberances in the right hemisphere in the patient group. Possible meanings and implications of these findings for a pathophysiological hypothesis are discussed.

Addictive Illegal Drugs: Structural Neuroimaging

SUMMARY: Illegal addictive drugs can lead to functional or structural impairment of the central nervous system. This review provides an overview of the structural imaging findings on CT, MR imaging, and conventional angiography related to chronic and acute abuse of the most commonly abused illegal drugs, including cannabis, organic solvents, and amphetamines and opioids and their respective derivatives. Pathomechanisms include excitotoxicity, which may lead to an acute or subacute leukoencephalopathy, and vascular complications, including vasoconstriction, vasculitis, or hypertension, which may lead to intracranial hemorrhage or ischemia. Because clinical findings alone are often nonspecific, and afflicted patients are unlikely to admit to the substance abuse, the neuroradiologist may play an important role in establishing the diagnosis and, thereby, initiating treatment.

Degenerative disorders of the spine

Patients with back pain and degenerative disorders of the spine have a significant impact on health care costs. Some authors estimate that up to 80% of all adults experience back pain at some point in their lives. Disk herniation represents one of the most frequent causes. Nevertheless, other degenerative diseases have to be considered. In this paper, pathology and imaging of degenerative spine diseases will be discussed, starting from pathophysiology of normal age-related changes of the intervertebral disk and vertebral body.

Brain morphology in schizophrenia by magnetic resonance imaging (MRI).

ABSTRACT— We report an in vivo Magnetic Resonance Imaging (MRI) Study of the brain in male schizophrenics and individually matched controls. Due to the multiplanar imaging capabilities of MRI we have obtained both midsagittal and axial scans. On the axial plane schizophrenics showed a significant increase of Ventricular Brain Ratio and on the sagittal plane a significant reduction of corpus callosum to brain ratio. In a factor analysis these two abnormalities loaded on components statistically independent suggesting different dimension of brain pathology in schizophrenia.

Alcohol-induced changes in the brain as assessed by MRI and CT

This review provides an overview of structural magnetic resonance imaging and computed tomography findings of direct and indirect alcohol-related toxic effects on the brain. In addition to ethanol-related changes to the brain, this article will also describe imaging findings in the acute setting of methanol and ethylene glycol poisoning. Alcohol will lead to brain atrophy, osmotic myelinolysis, Marchiafava–Bignami disease and, especially when related to malnutrition, may also cause Wernicke encephalopathy. Brain atrophy can be reversible if alcohol abuse is stopped. If not treated, Wernicke encephalopathy can lead to coma and death and an early diagnosis is important for immediate initiation of thiamine substitution. As clinical symptoms are often unspecific, the radiologist plays an important role in the detection of alcohol abuse and its related clinical conditions.

Does postcontrast MR enhancement in lumbar disk herniation have prognostic value

Objective The aim of our study was to evaluate the prognostic value, if any, of Gd-enhanced MR in pateints with lumbar disk herniation. Materials and Methods Fifteen patients undergoing conservative treatment for acute lumbar disk herniation were included in a prospective Gd-DTPA follow-up MR study. In each patient, the size of the herniation was measured, and, according to the changes in pathology that occurred, patients were divided into four categories. In addition, on the basis of the clinical outcome patients were divided into three classes. Results In 11 of 15 patients, MR performed in the acute phase of the disease showed Gd-DTPA enhancement around the herniated disk; in all cases, disk herniation was markedly reduced at follow-up MRIs. The clinical outcome was good. In the remaining four cases, no enhancement was evident in the acute phase or at follow-up MRIs: no modification in the size of disk herniation was demonstrated at follow-up in two. Symptoms were unchanged in two patients and mildly improved in one. Conclusion Epidural enhancement, which is likely related to an inflammatory process, seems to play a role in the modification of the size of disk herniation.