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1.
Stroke ; 55(3): 634-642, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38299371

RESUMO

BACKGROUND: The identification of patients surviving an acute intracerebral hemorrhage who are at a long-term risk of arterial thrombosis is a poorly defined, crucial issue for clinicians. METHODS: In the setting of the MUCH-Italy (Multicenter Study on Cerebral Haemorrhage in Italy) prospective observational cohort, we enrolled and followed up consecutive 30-day intracerebral hemorrhage survivors to assess the long-term incidence of arterial thrombotic events, to assess the impact of clinical and radiological variables on the risk of these events, and to develop a tool for estimating such a risk at the individual level. Primary end point was a composite of ischemic stroke, myocardial infarction, or other arterial thrombotic events. A point-scoring system was generated by the ß-coefficients of the variables independently associated with the long-term risk of arterial thrombosis, and the predictive MUCH score was calculated as the sum of the weighted scores. RESULTS: Overall, 1729 patients (median follow-up time, 43 months [25th to 75th percentile, 69.0]) qualified for inclusion. Arterial thrombotic events occurred in 169 (9.7%) patients. Male sex, diabetes, hypercholesterolemia, atrial fibrillation, and personal history of coronary artery disease were associated with increased long-term risk of arterial thrombosis, whereas the use of statins and antithrombotic medications after the acute intracerebral hemorrhage was associated with a reduced risk. The area under the receiver operating characteristic curve of the MUCH score predictive validity was 0.716 (95% CI, 0.56-0.81) for the 0- to 1-year score, 0.672 (95% CI, 0.58-0.73) for the 0- to 5-year score, and 0.744 (95% CI, 0.65-0.81) for the 0- to 10-year score. C statistic for the prediction of events that occur from 0 to 10 years was 0.69 (95% CI, 0.64-0.74). CONCLUSIONS: Intracerebral hemorrhage survivors are at high long-term risk of arterial thrombosis. The MUCH score may serve as a simple tool for risk estimation.


Assuntos
Fibrilação Atrial , Infarto do Miocárdio , Acidente Vascular Cerebral , Trombose , Humanos , Masculino , Fibrilação Atrial/complicações , Hemorragia Cerebral/diagnóstico por imagem , Hemorragia Cerebral/epidemiologia , Hemorragia Cerebral/complicações , Infarto do Miocárdio/complicações , Fatores de Risco , Acidente Vascular Cerebral/epidemiologia , Trombose/etiologia , Trombose/complicações , Feminino
2.
Artigo em Inglês | MEDLINE | ID: mdl-38937074

RESUMO

BACKGROUND: Whether statin use after spontaneous intracerebral haemorrhage (ICH) increases the risk of recurrent ICH is uncertain. METHODS: In the setting of the Multicentric Study on Cerebral Haemorrhage in Italy we followed up a cohort of 30-day ICH survivors, consecutively admitted from January 2002 to July 2014, to assess whether the use of statins after the acute event is associated with recurrent cerebral bleeding. RESULTS: 1623 patients (mean age, 73.9±10.3 years; males, 55.9%) qualified for the analysis. After a median follow-up of 40.5 months (25th to 75th percentile, 67.7) statin use was not associated with increased risk of recurrent ICH either in the whole study group (adjusted HR, 0.99; 95% CI 0.64 to 1.53) or in the subgroups defined by haematoma location (deep ICH, adjusted HR, 0.74; 95% CI 0.35 to 1.57; lobar ICH, adjusted HR, 1.09; 95% CI 0.62 to 1.90), intensity of statins (low-moderate intensity statins, adjusted HR, 0.93; 95% CI 0.58 to 1.49; high-intensity statins, adjusted HR, 1.48; 95% CI 0.66 to 3.31) and use of statins before the index event (adjusted HR, 0.66; 95% CI 0.38 to 1.17). CONCLUSIONS: Statin use appears to be unrelated to the risk of ICH recurrence.

3.
Neurol Sci ; 45(3): 1249-1254, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-38044394

RESUMO

INTRODUCTION: Posterior reversible encephalopathy syndrome (PRES) is a rare and complex disorder with variable clinical presentation and a typical magnetic resonance imaging (MRI) pattern of vasogenic edema with typical and atypical locations. It is often triggered by other diseases and drugs and the most prototypical association is with persistently elevated arterial pressure values. Among the potential cerebrovascular complications, intracranial bleeding has been described, but ischemic stroke is uncommonly reported. METHODS: We are presenting a case of a male patient with prolonged and sustained arterial hypertension acutely presenting with lacunar ischemic stroke involving the right corona radiata and composite MRI findings with the association of chronic small vessel disease (SVD) markers, acute symptomatic lacunar stroke, and atypical, central variant, posterior fossa dominant PRES. In the MRI follow-up, the white matter hyperintensities in T2-fluid attenuated inversion recovery (FLAIR sequences) due to PRES. DISCUSSION: The pathophysiology of PRES is not yet fully known, but the association with markedly increased values of arterial pressure is typical. In this context, ischemic stroke has not been considered in the clinical and neuroradiological manifestations of PRES and it has been only occasionally reported in the literature. In this case, the main hypothesis is that sustained hypertension may have triggered both manifestations, PRES, and ischemic stroke and the last one allowed to diagnose the first one. CONCLUSIONS: Atypical variants of PRES are not so rare and it may also occur in typical triggering situations. The association with ischemic stroke is even rarer and it may add some clues to the pathomechanisms of PRES.


Assuntos
Hipertensão , AVC Isquêmico , Síndrome da Leucoencefalopatia Posterior , Acidente Vascular Cerebral Lacunar , Substância Branca , Humanos , Masculino , Síndrome da Leucoencefalopatia Posterior/complicações , Síndrome da Leucoencefalopatia Posterior/diagnóstico por imagem , AVC Isquêmico/complicações , Hipertensão/complicações , Imageamento por Ressonância Magnética/métodos , Acidente Vascular Cerebral Lacunar/complicações , Acidente Vascular Cerebral Lacunar/diagnóstico por imagem
4.
Neurol Sci ; 45(8): 4037-4042, 2024 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-38709382

RESUMO

INTRODUCTION: Calcified arterial cerebral embolism is a rare occurrence among large and medium vessel occlusions causing ischemic stroke and its diagnosis and treatment is a challenge. The sources of calcified embolism might be a calcific atheroma from the aortic arch and carotid artery, but also heart valve disease has been reported in the literature. Calcified embolism is frequently simultaneous on multiple vascular territories. The prognosis of patients is usually poor, including patients treated by using endovascular thrombectomy (EVT) and this diagnosis could be easily missed in the acute phase. In addition, the optimal secondary prevention has not been yet fully stated. METHODS: We are presenting two cases of acute stroke due to calcified embolism in the middle cerebral artery (MCA) coming from a complicated carotid atheroma, non-stenosing in the first case (a 49 years old man) and stenosing in the second case (a 71 years old man) without clinical indications to intravenous thrombolysis and/or EVT, extensively investigated in the acute phase and followed-up for over 12 months with a favorable clinical course and the persisting steno-occlusion in the involved MCA. In both cases, antiplatelet treatment and targeting of vascular risk factors were done without recurrences in the follow-up period. DISCUSSION: Cerebral calcified embolism has been reported in 5.9% of cases of acute ischemic stroke in a single center series and only in 1.2% of a large retrospective cohort of EVT-treated patients. In both series the prognosis was poor and only one third of EVT-treated patients had functional independence at 3-months follow-up. The natural history of these subtype of ischemic stroke is relatively poorly understood and both etiological diagnosis and treatment have not yet defined. It is possible that some cases might be underdiagnosed and underreported. CONCLUSIONS: Calcified cerebral embolism is a rare cause of stroke, but it is largely underreported and both acute phase and secondary preventive treatment have to be defined.


Assuntos
Embolia Intracraniana , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Embolia Intracraniana/etiologia , Embolia Intracraniana/diagnóstico por imagem , Calcinose/complicações , Calcinose/diagnóstico por imagem , Infarto da Artéria Cerebral Média/diagnóstico por imagem , Infarto da Artéria Cerebral Média/complicações
5.
Neurol Sci ; 45(9): 4161-4171, 2024 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-38724752

RESUMO

Cerebellar mutism syndrome (CMS) is a frequent complication of surgical intervention on posterior fossa in children. It has been only occasionally reported in adults and its features have not been fully characterized. In children and in young adults, medulloblastoma is the main reason for neurosurgery. A single case of postsurgical CMS is presented in an adult patient with a cerebellar hemorrhage and a systematic review of the published individual cases of CMS in adults was done. Literature review of individual cases found 30 patients, 18/30 (60%) males, from 20 to 71 years at diagnosis. All but one case was post-surgical, but in one of the post-surgical cases iatrogenic basilar artery occlusion was proposed as cause for CMS. The causes were: primary tumors of the posterior fossa in 16/22 (72.7%) metastasis in 3/30 (10%), ischemia in 3/30 (10%) cerebellar hemorrhage in 3/30 (10%), and benign lesions in 2/30 (6.7%) patients. 8/30 patients (26.7%) were reported as having persistent or incomplete resolution of CMS within 12 months. CMS is a rare occurrence in adults and spontaneous cerebellar hemorrhage has been reported in 3/30 (10%) adult patients. The generally accepted hypothesis is that CMS results from bilateral damage to the dentate nucleus or the dentate-rubro-thalamic tract, leading to cerebro-cerebellar diaschisis. Several causes might contribute in adults. The prognosis of CMS is slightly worse in adults than in children, but two thirds of cases show a complete resolution within 6 months.


Assuntos
Mutismo , Humanos , Mutismo/etiologia , Masculino , Adulto , Doenças Cerebelares/etiologia , Doenças Cerebelares/diagnóstico por imagem , Hemorragias Intracranianas/etiologia , Hemorragias Intracranianas/diagnóstico por imagem , Hemorragias Intracranianas/complicações , Pessoa de Meia-Idade
6.
Adv Exp Med Biol ; 1457: 125-141, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39283424

RESUMO

Neurological manifestations are frequent in patients with SARS-CoV-2 infection and can be correlated with different pathogenic mechanisms which can be divided into two categories: direct invasion of the central nervous system by the virus and indirect effects deriving from the severity of the systemic infection and by the inflammatory response correlated with cytokine storm. Among the neurological manifestations, acute encephalopathy is very frequent and its nomenclature has recently been updated. The occurrence of a condition of altered mental status, reduced consciousness, delirium up to coma represents an element associated with a greater severity of the infection and mortality both in an Intensive Care Unit setting and in an Emergency Department setting. The tissue damage mechanisms found in COVID-19 patients' encephalopathy and neuroimaging patterns, as well as histopathology, are similar to those described in sepsis-associated encephalopathy, further confirming the role of indirect mechanisms, with no CNS invasion by the virus. The available data have some limitations, notably the underuse of diagnostic neuroimaging techniques in severely affected patients, particularly in the first wave of the pandemic.


Assuntos
COVID-19 , Neuroimagem , SARS-CoV-2 , Humanos , COVID-19/complicações , COVID-19/diagnóstico por imagem , Neuroimagem/métodos , SARS-CoV-2/patogenicidade , Encefalopatias/diagnóstico por imagem , Encefalopatias/virologia , Encéfalo/diagnóstico por imagem , Encéfalo/patologia , Encéfalo/virologia , Doença Aguda
7.
Adv Exp Med Biol ; 1457: 111-123, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39283423

RESUMO

Coronavirus disease 2019 (COVID-19) has been associated with a variety of neurological manifestations (i.e., anosmia, ageusia, myalgia, headache) and neurological syndromes (i.e., encephalopathy, ischemic and hemorrhagic stroke, myelitis, encephalitis) underlying different pathogenetic mechanisms. COVID-19 has also been associated with various movement disorders including acute or subacute parkinsonism. However, to date, only few cases of parkinsonism linked to COVID-19 have been reported, nevertheless raising the possibility of a post-viral parkinsonian syndrome. Furthermore, various studies in vitro and in animal models have highlighted a close relationship between SARS-CoV-2 virus and α-synuclein, leading to the hypothesis that COVID-19 could represent a factor favoring the long-term development of α-synucleopathies. In this chapter, we will discuss the pathophysiological mechanisms related to movement disorders' manifestations of COVID-19 focusing on the possible overlap between pathogenetic mechanisms of Parkinson's Disease and COVID-19.


Assuntos
COVID-19 , SARS-CoV-2 , Humanos , COVID-19/complicações , COVID-19/fisiopatologia , COVID-19/virologia , SARS-CoV-2/patogenicidade , alfa-Sinucleína/metabolismo , Doenças dos Gânglios da Base/fisiopatologia , Doenças dos Gânglios da Base/etiologia , Doenças dos Gânglios da Base/virologia , Doença de Parkinson/fisiopatologia , Doença de Parkinson/complicações , Animais
8.
Surg Radiol Anat ; 2024 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-39225864

RESUMO

PURPOSE: Arterial supply of thalamus is complex and highly variable. In particular, the distribution pattern of thalamoperforating arteries received more attention some decades ago than in recent years. METHODS: We are presenting the case of a 46-year-old patient with wake-up drowsiness, complex oculomotor disorder and dysarthria. He was investigated in the acute phase using non-contrast brain Computed Tomography (NCCT), CT Angiography (CTA), and in the following days Digital Subtraction Angiography (DSA) was performed Results. The NCCT showed a subacute ischemic stroke in the right anterior thalamus and rostral midbrain with normal findings on CTA. DSA imaged a variant of thalamic supply (Percheron type III), constituted by perforating branches arising from an artery bridging the P1 segments of both Posterior Cerebral Arteries (PCAs). RESULTS: The thalamus has a complex and variable arterial supply, mainly in the pattern of paramedian thalamic-mesencephalic perforating arteries. The most reported variant is Percheron type IIb and supplies the paramedian thalami and the rostral midbrain. Type IIb occlusion usually causes a bilateral paramedian thalamic stroke, but rostral midbrain and anterior thalamus are involved in 57% and 19% cases. The rarer Type III variant probably prevented the bilateral extension of infarction and involved the territory of tuberothalamic and paramedian perforating arteries. CONCLUSIONS: Currently, DSA allows directly imaging variants in thalamic vascularization and better understanding the stroke mechanisms. In particular, in the presented case, a medium-sized vessel occlusion rather than a small vessel occlusion mechanism might be raised, leading to a different diagnostic pathway.

9.
Neurol Sci ; 44(11): 4099-4102, 2023 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-37526798

RESUMO

INTRODUCTION: Secondary neurodegeneration after stroke is a complex phenomenon affecting remote and synaptically linked cerebral areas. The involvement of the substantia nigra in this process has been rarely described in infarcts involving the striatum. METHODS: We are presenting a case of ischemic stroke involving the right striatum due to atrial fibrillation and associated in a few days with the neuroimaging finding of hyperintensity of the ipsilateral substantia nigra and striatonigral tract on T2-fluid attenuated inversion recovery and diffusion-weighted imaging sequences of brain magnetic resonance imaging. This finding was not related to clinical manifestations and substantially disappeared within 3 months from stroke onset. DISCUSSION: The pathophysiology of secondary degeneration of the substantia nigra is poorly understood and it relies on animal models and autoptic studies. The main putative mechanism is not ischemic but excitotoxic with a different role of the internal and external globus pallidus and a different effect on the pars compacta and pars reticularis of the substantia nigra. In animal models, inflammatory mechanisms seem play a role only in the late phase. The main studies on humans were presented in detail. CONCLUSIONS: A better understanding of the secondary degeneration of the substantia nigra has the potentiality to offer a chance for neuroprotection in acute stroke, but further studies are needed.


Assuntos
AVC Isquêmico , Acidente Vascular Cerebral , Humanos , Corpo Estriado/patologia , AVC Isquêmico/patologia , Imageamento por Ressonância Magnética , Acidente Vascular Cerebral/complicações , Acidente Vascular Cerebral/diagnóstico por imagem , Acidente Vascular Cerebral/patologia , Substância Negra/diagnóstico por imagem , Substância Negra/patologia
10.
Neurogenetics ; 22(1): 19-25, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-32816121

RESUMO

Basel-Vanagaite-Smirin-Yosef syndrome (BVSYS) is an extremely rare autosomal recessive genetic disorder caused by variants in the MED25 gene. It is characterized by severe developmental delay and variable craniofacial, neurological, ocular, and cardiac anomalies. Since 2015, through whole exome sequencing, 20 patients have been described with common clinical features and biallelic variants in MED25, leading to a better definition of the phenotype associated with BVSYS. We report two young sisters, born to consanguineous parents, presenting with intellectual disability, neurological findings, and dysmorphic features typical of BVSYS, and also with bilateral perisylvian polymicrogyria. The younger sister died at the age of 1 year without autoptic examination. Whole exome sequencing detected a homozygous frameshift variant in the MED25 gene: NM_030973.3:c.1778_1779delAG, p.(Gln593Argfs). This report further delineates the most common clinical features of BVSYS and points to polymicrogyria as a distinctive neuroradiological feature of this syndrome.


Assuntos
Anormalidades Múltiplas/genética , Deficiências do Desenvolvimento/genética , Deficiência Intelectual/genética , Malformações do Desenvolvimento Cortical/genética , Complexo Mediador/genética , Mutação/genética , Polimicrogiria/genética , Criança , Hibridização Genômica Comparativa , Feminino , Humanos , Masculino , Linhagem , Fenótipo , Polimicrogiria/diagnóstico
11.
Am J Med Genet A ; 182(11): 2675-2679, 2020 11.
Artigo em Inglês | MEDLINE | ID: mdl-32875707

RESUMO

The CAMK2B gene encodes the ß-subunit of calcium/calmodulin-dependent protein kinase II (CAMK2), an enzyme that has crucial roles in synaptic plasticity, especially in hippocampal and cerebellar neurons. Heterozygous variants in CAMK2B cause a rare neurodevelopmental disorder, with 40% of the reported cases sharing the same variant: c.416C>T, p.(P139L). This case report describes a 22-year-old patient with this recurrent variant, who presents with severe intellectual disability, absence of language, hypotonia, microcephaly, dysmorphic features, epilepsy, behavioral abnormalities, motor stereotypies, optic atrophy, and progressive cerebellar atrophy. Notably, this patient is the oldest reported so far and allows us to better delineate the clinical phenotype associated with this variant, adding clinical aspects never described before, such as epilepsy, optic atrophy, scoliosis, and neuroradiological changes characterized by progressive cerebellar atrophy.


Assuntos
Proteína Quinase Tipo 2 Dependente de Cálcio-Calmodulina/genética , Epilepsia/patologia , Deficiência Intelectual/patologia , Transtornos da Linguagem/patologia , Mutação , Atrofias Olivopontocerebelares/patologia , Adulto , Epilepsia/genética , Feminino , Humanos , Deficiência Intelectual/genética , Transtornos da Linguagem/genética , Atrofias Olivopontocerebelares/genética , Fenótipo , Prognóstico , Adulto Jovem
12.
BMC Neurol ; 20(1): 382, 2020 Oct 21.
Artigo em Inglês | MEDLINE | ID: mdl-33087049

RESUMO

BACKGROUND: Glioblastoma (GBM) is known for its devastating intracranial infiltration and its unfavorable prognosis, while extracranial involvement is a very rare event, more commonly attributed to IDH wild-type (primary) GBM evolution. CASE PRESENTATION: We present a case of a young woman with a World Health Organization (WHO) grade II Astrocytoma evolved to WHO grade IV IDH mutant glioblastoma, with subsequent development of lymphatic and bone metastases, despite the favorable biomolecular pattern and the stability of the primary brain lesion. CONCLUSIONS: Our case highlights that grade II Astrocytoma may evolve to a GBM and rarely lead to a secondary metastatic diffusion, which can progress quite rapidly; any symptoms referable to a possible systemic involvement should be carefully investigated.


Assuntos
Neoplasias Ósseas/secundário , Neoplasias Encefálicas , Glioblastoma , Metástase Linfática , Segunda Neoplasia Primária , Adulto , Astrocitoma/patologia , Neoplasias Encefálicas/patologia , Neoplasias Encefálicas/secundário , Feminino , Glioblastoma/patologia , Glioblastoma/secundário , Humanos
17.
Int J Neurosci ; 125(4): 307-11, 2015 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-24831262

RESUMO

Acute nontraumatic myelopathies include vascular etiologies most commonly caused by atherosclerotic vascular disease. Other causes that have been reported to occur with varying frequencies include thrombosis, embolism of thrombi and tumor, arteritis, hypotension, dissecting aortic aneurysm, sickle cell disease, intervertebral disk herniation, vertebral body subluxation and iatrogenic causes, usually angiography or surgery. In case of acutely progressing spinal cord syndromes, the diagnosis often given is of transverse myelitis or unknown cause of infarction. Fibrocartilaginous embolism (FCE) is possible cause of spinal ischemia due to embolization of nucleus pulposus fragments through retrograde spinal artery flow. A young woman after intensive exercise developed profound weakness of her upper extremities, progressing to flaccid quadriplegia with sensory level from C3 dermatome. Magnetic resonance imaging (MRI) showed linear hyperintense intramedullary lesion from C2 to Th2 confined to anterior horn area, with typical"owl's eye" appearance. Although exact mechanism of patient's neurological syndrome remains undetermined, we suspected a cord infarction due to FCE related to her vigorous physical exercise.


Assuntos
Quadriplegia/diagnóstico , Doença Aguda , Adulto , Feminino , Humanos , Imageamento por Ressonância Magnética
18.
World Neurosurg ; 183: e11-e21, 2024 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-37806521

RESUMO

OBJECTIVES: Twig-like middle cerebral artery (MCA) is a rare anomaly where the M1 MCA is partially or completely replaced by a plexiform network. It has been described in angiographic series from Asian and South-American cohorts, but has not yet been reported in a European population. METHODS: The digital subtraction angiograms (DSAs) of adult patients referred to a single neurovascular center for a diagnostic hypothesis of moyamoya arteriopathy (MMA) from 2018 to 2023 were prospectively and retrospectively checked by experienced neuroradiologists for identifying patients with twig-like MCA. The angioarchitecture of twig-like MCA was systematically evaluated and described. RESULTS: Five of 30 (16.7%) male patients (mean age 55.8 + 14.7 years) of European ancestry were identified as having twig-like MCA. The clinical presentations were ischemic stroke (2 of 5), hemorrhagic stroke (1 of 5), and headache (2 of 5). All patients showed a unilateral involvement on DSA and in 1 of 5 (20%) an intracranial aneurysm was found. DSA was used to confirm the diagnosis of twig-like MCA and define the angioarchitecture and associated anomalies. An accessory MCA and recurrent artery of Heubner were found in 3 of 5 (60%) cases, feeding the network together with the anterior choroidal artery (4 of 5, 80%). CONCLUSIONS: Twig-like MCA is a rare vascular anomaly, but it seems to be less rare than expected among adult European patients with suspected MMA on noninvasive neuroimaging studies. DSA is fundamental for a reliable differential diagnosis and should not be omitted in these patients.


Assuntos
Aneurisma Intracraniano , Doença de Moyamoya , Adulto , Humanos , Masculino , Pessoa de Meia-Idade , Idoso , Feminino , Artéria Cerebral Média/diagnóstico por imagem , Artéria Cerebral Média/anormalidades , Estudos Retrospectivos , Artérias Cerebrais , Artéria Carótida Interna , Angiografia Cerebral
19.
Biomedicines ; 12(2)2024 Feb 19.
Artigo em Inglês | MEDLINE | ID: mdl-38398061

RESUMO

Primary Angiitis of the Central Nervous System (PACNS) is a rare cerebrovascular disease involving the arteries of the leptomeninges, brain and spinal cord. Its diagnosis can be challenging, and the current diagnostic criteria show several limitations. Among the clinical and neuroimaging manifestations of PACNS, intracranial bleeding, particularly intracerebral hemorrhage (ICH), is poorly described in the available literature, and it is considered infrequent. This review aims to summarize the available data addressing this issue with a dedicated focus on the clinical, neuroradiological and neuropathological perspectives. Moreover, the limitations of the actual data and the unanswered questions about hemorrhagic PACNS are addressed from a double point of view (PACNS subtyping and ICH etiology). Fewer than 20% of patients diagnosed as PACNS had an ICH during the course of the disease, and in cases where ICH was reported, it usually did not occur at presentation. As trigger factors, both sympathomimetic drugs and illicit drugs have been proposed, under the hypothesis of an inflammatory response due to vasoconstriction in the distal cerebral arteries. Most neuroradiological descriptions documented a lobar location, and both the large-vessel PACNS (LV-PACNS) and small-vessel PACNS (SV-PACNS) subtypes might be the underlying associated phenotypes. Surprisingly, amyloid beta deposition was not associated with ICH when histopathology was available. Moreover, PACNS is not explicitly included in the etiological classification of spontaneous ICH. This issue has received little attention in the past, and it could be addressed in future prospective studies.

20.
J Clin Med ; 13(7)2024 Mar 28.
Artigo em Inglês | MEDLINE | ID: mdl-38610734

RESUMO

Secondary neurodegeneration refers to the final result of several simultaneous and sequential mechanisms leading to the loss of substance and function in brain regions connected to the site of a primary injury. Stroke is one of the most frequent primary injuries. Among the subtypes of post-stroke secondary neurodegeneration, axonal degeneration of the corticospinal tract, also known as Wallerian degeneration, is the most known, and it directly impacts motor functions, which is crucial for the motor outcome. The timing of its appearance in imaging studies is usually considered late (over 4 weeks), but some diffusion-based magnetic resonance imaging (MRI) techniques, as diffusion tensor imaging (DTI), might show alterations as early as within 7 days from the stroke. The different sequential pathological stages of secondary neurodegeneration provide an interpretation of the signal changes seen by MRI in accordance with the underlying mechanisms of axonal necrosis and repair. Depending on the employed MRI technique and on the timing of imaging, different rates and thresholds of Wallerian degeneration have been provided in the literature. In fact, three main pathological stages of Wallerian degeneration are recognizable-acute, subacute and chronic-and MRI might show different changes: respectively, hyperintensity on T2-weighted sequences with corresponding diffusion restriction (14-20 days after the injury), followed by transient hypointensity of the tract on T2-weighted sequences, and by hyperintensity and atrophy of the tract on T2-weighted sequences. This is the main reason why this review is focused on MRI signal changes underlying Wallerian degeneration. The identification of secondary neurodegeneration, and in particular Wallerian degeneration, has been proposed as a prognostic indicator for motor outcome after stroke. In this review, the main mechanisms and neuroimaging features of Wallerian degeneration in adults are addressed, focusing on the time and mechanisms of tissue damage underlying the signal changes in MRI.

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