Changes in the basal ganglia and thalamus following reperfusion after complete cerebral ischaemia

Bilateral basal ganglia hemorrhage: a systematic review of etiologies, management strategies, and clinical outcomes

Bilateral basal ganglia hemorrhages (BBGHs) represent rare accidents, with no clear standard of care currently defined. We reviewed the literature on BBGHs and analyzed the available conservative and surgical strategies. PubMed, Scopus, Web of Science, and Cochrane were searched following the PRISMA guidelines to include studies reporting patients with BBGHs. Clinical characteristics, management, and outcomes were analyzed. We included 64 studies comprising 75 patients, 25 (33%) traumatic and 50 (67%) non-traumatic. Traumatic cases affected younger patients (mean age 35 vs. 46 years, p=0.014) and males (84% vs. 71%, p=0.27) and were characterized by higher proportion of normal blood pressures at admission (66% vs. 13%, p=0.0016) compared to non-traumatic cases. Most patients were comatose at admission (56%), with a mean Glasgow Coma Scale (GCS) score of 7 and a higher proportion of comatose patients in the traumatic than in the non-traumatic group (64% vs. 52%, p=0.28). Among the traumatic group, motor vehicle accidents and falls accounted for 79% of cases. In the non-traumatic group, hemorrhage was most associated with hypertensive or ischemic (54%) and chemical (28%) etiologies. Management was predominantly conservative (83%). Outcomes were poor in 56% of patients with mean follow-up of 8 months. Good recovery was significantly higher in the traumatic than in the non-traumatic group (48% vs. 17%, p=0.019). BBGHs are rare occurrences with dismal prognoses. Standard management follows that of current intracerebral hemorrhage guidelines with supportive care and early blood pressure management. Minimally invasive surgery is promising, though substantial evidence is required to outweigh the potentially increased risks of bilateral hematoma evacuation.

Hemorrhagic infarct of basal ganglia in cardiac arrest. CT and MRI findings. 2 cases

We report the CT and MRI findings in two cases of hemorrhagic infarct of the basal ganglia (BG), following out-of-hospital cardiac arrest (CA). In case 1, Brain-CT realized at day 2 showed bilateral and almost symmetric hemorrhagic infarct of the BG and infarct of the tectum of the mesencephalon. In case 2, MRI realized at day 6 showed hemorrhagic infarct of both lenticular nuclei on T2 GE images. In both cases there was no medical history and the cardiovascular and the coagulation profile were normal. In these cases, the lesions are observed earlier than reported in a few previous radiological cases. Similar lesions have been reported in pathological studies. These lesions seem occur early after CA. Reperfusion is probably responsible for the hemorrhagic transformation. The reason why some patients present either BG or brainstem infarct or both remains unclear. Bilateral and symmetric hemorrhagic infarct of the BG, especially of the Lenticular nuclei, and infarct of the dorsal pons and mesencephalic tegmentum seem to be a characteristic feature of profound and prolonged hypotension or of CA.

Long-term increase in coherence between the basal ganglia and motor cortex after asphyxial cardiac arrest and resuscitation in developing rats

BACKGROUND

The basal ganglia are vulnerable to injury during cardiac arrest. Movement disorders are a common morbidity in survivors. Yet, neuronal motor network changes post-arrest remain poorly understood.

METHODS

We compared function of the motor network in adult rats that, during postnatal week 3, underwent 9.5 min of asphyxial cardiac arrest (n = 9) or sham intervention (n = 8). Six months after injury, we simultaneously recorded local field potentials (LFP) from the primary motor cortex (MCx) and single neuron firing and LFP from the rat entopeduncular nucleus (EPN), which corresponds to the primate globus pallidus pars interna. Data were analyzed for firing rates, power, and coherence between MCx and EPN spike and LFP activity.

RESULTS

Cardiac arrest survivors display chronic motor deficits. EPN firing rate is lower in cardiac arrest survivors (19.5 ± 2.4 Hz) compared with controls (27.4 ± 2.7 Hz; P < 0.05). Cardiac arrest survivors also demonstrate greater coherence between EPN single neurons and MCx LFP (3-100 Hz; P < 0.001).

CONCLUSIONS

This increased coherence indicates abnormal synchrony in the neuronal motor network after cardiac arrest. Increased motor network synchrony is thought to be antikinetic in primary movement disorders. Characterization of motor network synchrony after cardiac arrest may help guide management of post-hypoxic movement disorders.

Cryptogenic stroke in hanging. A case report

This paper reports the unique neuroimaging findings of a 37-year-old woman who attempted suicide by hanging. To our knowledge, this is the first reported case describing neuroimaging findings of unilateral lesions instead of the well-documented bilateral lesions after a hanging event. Computed tomography demonstrated a low density area in the right thalamus and no hemorrhage. 3.0 T Magnetic resonance revealed a hyperintense area on both T2-weighted and FLAIR images on the right thalamus. Diffusion weighted images demonstrated no area of diffusivity restriction. Another smaller lesion with the same signal characteristics was found in the left cerebellum. A second relevant point of this report is the observation that the most probable cause of the documented unilateral lesions was an ischemic-arterial event.

Blindness and basal ganglia hypoxia as a complication of Le Fort I osteotomy attributable to hypoplasia of the internal carotid artery: a case report

Le Fort I osteotomy is used as a surgical procedure for correction of maxillofacial deformities. The common complications of this procedure are hemorrhage and infection, with incidence of 6% to 9%. Blindness associated with Le Fort I osteotomy was reported in 8 patients. An 18-year-old female complained of loss of sight in the left eye after recovery from hypotensive general anesthesia. The visual field of the left eye was dark and only perceived some movement. She presented with motor dysfunction and regressive behavior 2 weeks later as a result of hypoxia of bilateral basal ganglia. Two months later, her visual acuity recovered gradually and regressive behavior improved. Carotid angiography showed congenital hypoplasia of the left internal carotid artery. We suspected that hypoplasia could cause hypoxia of the central nervous system.

Diffusion-weighted magnetic resonance imaging in the syndrome of acute bilateral basal ganglia lesions in diabetic uremia

In this report, we have presented a diabetic patient with uremia, in which acute Parkinsonism occurred, coupled with acute mental confusion, after a sudden increase in blood urea nitrogen and serum creatinin levels. Diffusion-weighted magnetic resonance imaging revealed a unique cytotoxic-type edema in the bilateral basal ganglia during the acute phase. Signal alterations were shown to regress in accordance with the normalized apparent diffusion coefficient (ADC) values, but irreversible cystic degeneration developed in the globus pallidus, with the very low preceding ADC values.

Computed tomography and magnetic resonance imaging findings of brain damage by hanging

We reported computed tomography (CT) and magnetic resonance imaging (MRI) findings of brain damage of a 61-year-old man who attempted suicide by hanging. Unenhanced CT demonstrated multiple hyperdense areas indicating subcortical and subarachnoid hemorrhages and brain swelling. MRI demonstrated not only hemorrhagic findings, but also ischemic findings in the middle brain and cerebral cortex. Multifocal cerebral hemorrhages might be caused by venous hypertension due to compression of the jugular veins.

Hypotensive hemorrhagic necrosis in basal ganglia and brainstem

Hypotensive hemorrhagic necrosis of the basal ganglia and brainstem has only occasionally been described. Three such cases are reported. Cardiac arrest had occurred in all cases, and it took at least 1 hour to restore adequate circulation. The patients remained comatose for 2 days to 2 weeks until death. Persistent hypotension causing ischemia in the distribution of deep perforating arteries is considered to have been the key underlying mechanism. Hemorrhage is thought to have been caused by extravasation of red blood cells through damaged blood vessels.

Reperfusion in a gerbil model of forebrain ischemia using serial magnetic resonance FAIR perfusion imaging

BACKGROUND AND PURPOSE

Existing methods for the quantitative measurement of the changing cerebral blood flow (CBF) during reperfusion suffer from poor spatial or temporal resolution. The aim of this study was to implement a recently developed MRI technique for quantitative perfusion imaging in a gerbil model of reperfusion. Flow-sensitive alternating inversion recovery (FAIR) is a noninvasive procedure that uses blood water as an endogenous tracer.

METHODS

Bilateral forebrain ischemia of 4 minutes' duration was induced in gerbils (n=8). A modified version of FAIR with improved time efficiency was used to provide CBF maps with a time resolution of 2.8 minutes after recirculation had been initiated. Quantitative diffusion imaging was also performed at intervals during the reperfusion period.

RESULTS

On initiating recirculation after the transient period of ischemia, the FAIR measurements demonstrated either a symmetrical, bilateral pattern of flow impairment (n=4) or an immediate side-to-side difference that became apparent with respect to the cerebral hemispheres in the imaged slice (n=4). The flow in each hemisphere displayed a pattern of recovery close to the preocclusion level or, alternatively, returned to a lower level before displaying a delayed hypoperfusion and a subsequent slow recovery. The diffusion measurements during this latter response suggested the development of cell swelling during the reperfusion phase in the striatum.

CONCLUSIONS

The CBF during the reperfusion period was monitored with a high time resolution, noninvasive method. This study demonstrates the utility of MRI techniques in following blood flow changes and their pathophysiological consequences.

Acute movement disorders with bilateral basal ganglia lesions in uremia

Acute and subacute extrapyramidal movement disorders are rarely reported in uremic patients. We report three such cases with basal ganglia lesions. All three had advanced renal failure with high serum creatinine levels. One of the patients had a history of ischemic heart disease and acute pulmonary edema with hypoxemia. Another patient had experienced arterial hypotension during previous hemodialysis. The third had prominent metabolic acidosis. One of the patients developed generalized dyskinesias, whereas the other two developed gait disturbances. Neuroimaging studies in all three cases showed bilateral changes in the basal ganglia. The natural history was self-limiting with gradual improvement. Diminution of the basal ganglia lesions was demonstrated on follow-up imaging in two of the three cases. We conclude that acute or subacute movement disorders with bilateral basal ganglia lesions may occur in uremia. Hypoperfusion with global brain ischemia and selective vulnerability of the basal ganglia to uremic toxins may account for these lesions.

Adolescent case of Alexander disease: MR imaging and MR spectroscopy

A 17-year-old male was diagnosed as having Alexander disease from the clinical manifestations (psychomotor deterioration and megalencephaly), neuroradiologic findings (frontal dominant leukodystrophy), and elevation of alpha B-crystallin and heat shock protein 27 in the cerebrospinal fluid. He exhibited increased attenuation on computed tomography and T1 and T2 shortening on magnetic resonance imaging in the bilateral basal ganglia and thalamus. Some paramagnetic substances might be deposited in the basal ganglia and thalamus in the late stage of Alexander disease, at least 8 years after onset.

Specific changes in human brain after hypoglycemic injury

BACKGROUND AND PURPOSE

Very few reports are available on serial changes in the human brain after severe hypoglycemic injury. The aim of this study was to investigate sequential neuroradiological changes in brains of patients after hypoglycemic coma compared with those after cardiac arrest previously studied with the same methods.

METHODS

We repeatedly studied CT scans and MR images obtained at 1.5 T in four vegetative patients after profound hypoglycemia associated with diabetes mellitus.

RESULTS

In all patients, consecutive CT scans showed symmetrical, persistent low-density lesions with transient enhancement in the caudate and lenticular nuclei and transient enhancement in the cerebral cortex 7 to 14 days after onset. Serial MR images consistently revealed symmetrical lesions of persistent hyperintensity and hypointensity on T1- and T2-weighted images, respectively, in the caudate and lenticular nuclei, cerebral cortex, substantia nigra, and/or hippocampus from 8 days to 12 months after onset.

CONCLUSIONS

Repeated MR images revealed specific lesions in the bilateral basal ganglia, cerebral cortex, substantia nigra, and hippocampus, which suggests the particular vulnerability of these areas to hypoglycemia in the human brain. We speculate that the localized lesions represent tissue degeneration, including some combination of selective neuronal death, proliferation of astrocytic glial cells, paramagnetic substance deposition, and/or lipid accumulation. The absence of localized hemorrhages on MR images in hypoglycemic encephalopathy is in marked contrast to the presence of regional minor hemorrhages in postischemic-anoxic encephalopathy.