Periventricular leukomalacia complex. Clinical and pathologic correlates

In 1979, the appearance of the periventricular leukomalacia complex (PLC) was reported in a relatively high percent of infants coming to autopsy from our neonatal intensive care unit. Because infants with PLC had had longer periods of high P02 than did those without PLC, it was concluded that PLC was related to hyperoxia. However, in a second study it was found that the periods of hyperoxia corresponded to periods of hypotension. Therefore, the complete autopsies of 16 randomly selected newborn subjects with PLC and 21 without PLC were reviewed with particular reference to the incidence of bronchopulmonary dysplasia (BPD), a lesion thought to be due to high levels of oxygen in inspired air. The incidence of BPD in newborn subjects with PLC was essentially the same as in those without PLC (7/16 or 44% vs 9/21 or 43%). Moreover, three newborn subjects with PLC and none without PLC showed renal tubular necrosis, a lesion usually associated with severe hypotension. This suggests that PLC is related to hypotension rather than to hyperoxia.

Multicystic encephalomalacia in liveborn twin with a stillborn macerated co-twin

Computed tomography showed multiple cystic lesions in the brains of three infants with cerebral palsy. Each patient was the product of a twin pregnancy with a stillborn, macerated co-twin. In two patients angiography was performed and suggested that the cystic lesions were multicystic encephalomalacia due to perinatal arterial occlusion.

Polioencephalomalacia associated with canine distemper virus infection

Eight dogs with severe neurologic signs, including seizures, had polioencephalomalacia of the pyriform cortex, Ammon's horn and deep structures in the temporal lobe. The polioencephalomalacia was considered to be a consequence of canine distemper virus infection based on clinical signs, typical inclusions, the demonstration of viral antigens in the lesions and of characteristic paramyxovirus nucleocapsids by electron microscopy. Little evidence for neuronal destruction by direct viral activity was found. Selective nerve cell necrosis was attributed to ischemia (vascular lesions and seizure induced consumptive anoxia) and immune mechanisms. The selective involvement of the rhinencephalic structures was thought to be related to the mode of entry and spread of the virus.

[Natural history, treatment and outcome of cerebellar softening (author's transl)]

21 adults with acute cerebellar softening were divided into two groups. In the first group (6 patients) the clinical course was progressive with deterioration of consciousness, signs of brain-stem compression and some degree of enlargement of ventricles (CT scan). Of these patients, three were treated surgically with success, one recovered spontaneously and two others died post-operatively. In the second group (15 patients) the course was much more favourable. Without surgery the cerebellar symptoms and signs improved, in spite of the persistence of discrete cerebellar signs one month after the onset of symptoms. Medical and/or surgical treatment of the disease are discussed, including the differential diagnostic aspects as well as the CT scan features.

Polioencephalomalacia (cerebrocortical necrosis) induced by experimental thiamine deficiency in lambs

Lesions of polioencephalomalacia (PEM, cerebrocortical necrosis) have been demonstrated in pre-ruminant lambs fed on synthetic, thiamine-free milk. Thiamine deficiency in these lambs was confirmed by transketolase assay.

Multiple cystic encephalomalacia of infancy: computed tomographic findings in two cases with associated intracerebral calcification

Two initially healthy infants developed acute encephalopathic illnesses characterized by stupor, seizures, cerebrospinal fluid (CSF) erythrocytic and monocytic pleocytosis, increased CSF protein, and decreased CSF glucose and progression to chronic decerebration. In one case, herpes simplex virus was recovered from cutaneous lesions. The initial computed tomography (CT) scan revealed widespread subcortical increased attenuation with further increase after contrast medium injection and patchy areas of decreased attenuation in the deep cerebral white matter. Subsequent CT scans demonstrated progressive cortical calcifications and persistence of low attenuation areas. Autopsy revealed multiple cystic encephalomalacia. The second infant had similar clinical, CSF, and CT findings but remains in a chronic decerebrate state at 14 months of age. The CT abnormalities seen in these patients have not been encountered in any of 13 other infants with the clinical diagnosis of meningitis or encephalitis. Multiple cystic encephalomalacia of infancy is a rare condition with a uniformly bleak prognosis. Computed tomography may prove useful in the early diagnosis, thereby aiding clinicians in counseling and in the acute and long-term management of patients with this lesion.

Complex acid-base disorders in subacute necrotizing encephalomyelopathy (Leigh's syndrome)

This report describes a case of subacute necrotizing encephalomyelopathy (Leigh's syndrome) in a 7-month-old boy. The clinical data suggest an association with a disorder of renal tubular acidification, characterized by both (proximal) type II and (distal) type I renal tubular acidosis (hybrid type). Concomitantly, the initial uncompensated metabolic acidosis evolved into a mixed metabolic acidosis and respiratory alkalosis-features of this syndrome not previously reported.

Bilateral symmetrical softening of the thalamus

The clinical and pathological data of a 48 year old patient who survived 40 days are reported. Her disturbance of consciousness corresponded to an apallic syndrome, which 12 days later bacame akinetic mutism. Symmetrical softening involving the medial thalamic nuclei from the plane of the corpora mamillaria to the red nuclei was found. The ischemic lesion might be explained by transient circulatory collapse combined with hypoplasia of the vertebrobasialr arteries. On the EEG slight irregular alpha activity was recorded (alpha coma) and external stimuli elicited theta-delta waves (paradox activation). A survey of the literature of akinetic mutism is included and the correlation between non-hypnoid unconsciousness and EEG is discussed.

[Epilepsia partialis continua of Kozevnikov (author's transl)]

Continuous myoclonus in a localised area of the body was observed in three patients. In two cases the myocloni sometimes developed into motor Jacksonian convulsions. All three patients had neurological signs on the same side as their continuous twitching indicating a lesion of the contralateral hemisphere. The surface EEG did not show changes which could be directly correlated with continuous convulsions in any of the cases. The cause was found to be a malformation of the hemisphere in one case, a recent encephalomalacia in the second and a severe hyperosomolar diabetic electrolyte imbalance in the third. Epilepsia partialis continua Kozevnikov differs from motor Jacksonian epilepsy in the continuous non-attack character and the absence of a "march of convulsions". Pathophysiologically they are both forms of focal cortical status epilepticus.

[Clinical significance of changes in blood viscosity in cerebrovascular insufficiency (author's transl)]

In 50 patients with encephalomalacia and 50 patients with a transient cerebral ischemic attack (TIA) the risk factors and viscosity of the whole blood as well as the hematocrit were determined before the start of treatment. Compared to a control group, the blood viscosity in patients with encephalomalacia was significantly increased (p less than 0.001) in all ranges of shearing velocity tested, in patients with TIA only at that shearing velocity which may be assumed for the area of microcirculation. This increase was related to the presence of arterial hypertension, hyperlipemia, heart failure, diabetes mellitus, hyperfibrinogenemia and increased tendency of thrombocytes and erythrocytes to aggregate. From the results obtained it was concluded that increased blood viscosity in the cerebral area of microcirculation with insufficient cerebral collateral circulation may decisively favor the development of encephalomalacia.

[Subacute necrotizing encephalomyelopathy (Leigh's disease) (author's transl)]

The characteristic neuropathological features of subacute necrotizing encephalomyelopathy (Leigh), their histology and distribution are described. Clinical findings are unspecific. Impairment of feeding. vomitus, respiratory abnormality, retardation of psychomotor development, familial incidence and onset in early childhood are prominent symptoms. Atactic and athetoid movements, optic atrophy, oculomotor abnormalities are observed in most cases. An enzyme inhibitor excreted in the urine seems to be related to an inborn error of thiamine dependent metabolism in brain tissue. Treatment with thiamine derivatives may have a beneficial effect on the clinical course.