Frontal Lobe Involvement Research Articles

Intraoperative Seizures During Awake Craniotomy

Awake craniotomy (AC) for removal of intra-axial brain tumors is a well-established procedure. However, the occurrence and consequences of intraoperative seizures during AC have not been well characterized. To analyze the incidence, risk factors, and consequences of seizures during AC. The database of AC at Tel Aviv Medical Center between 2003 to 2011 was reviewed. Occurrences of intraoperative seizures were analyzed with respect to medical history, medications, tumor characteristics, and postoperative outcome. Of the 549 ACs performed during the index period, 477 with complete records were identified. Sixty patients (12.6%) experienced intraoperative seizures. The AC procedure failed in 11 patients (2.3%) due to seizures. Patients with intraoperative seizures were significantly younger than nonseizing patients (45 ± 14 years vs 52 ± 16 years, P = .003), had a higher incidence of frontal lobe involvement (86% vs % 57%, P < .0001), and had higher prevalence of a history of seizures (P = .008). Short-term motor deterioration developed postoperatively in a higher percentage of patients with intraoperative seizures (20% vs 10.1%, P = .02) with a longer hospitalization period (4.0 ± 3.0 days vs 3.0 ± 3.0 days, P = .045). Although in most cases intraoperative seizures will not result in AC failure, the surgical team should be prepared to treat them promptly to avoid intractable seizures. Intraoperative seizures are more common in younger patients with a tumor in the frontal lobe and those with a history of seizures. Moreover, they are associated with a higher incidence of transient postoperative motor deterioration and protracted length of hospital stay.

Dorsolateral prefrontal and orbitofrontal cortex interactions during self-control of cigarette craving

Drug-related cues induce craving, which may perpetuate drug use or trigger relapse in addicted individuals. Craving is also under the influence of other factors in daily life, such as drug availability and self-control. Neuroimaging studies using drug cue paradigms have shown frontal lobe involvement in this contextual influence on cue reactivity, but have not clarified how and which frontal area accounts for this phenomenon. We explored frontal lobe contributions to cue-induced drug craving under different intertemporal drug availability conditions by combining transcranial magnetic stimulation and functional magnetic resonance imaging in smokers. We hypothesized that the dorsolateral prefrontal cortex (DLPFC) regulates craving during changes in intertemporal availability. Subjective craving was greater when cigarettes were immediately available, and this effect was eliminated by transiently inactivating the DLPFC with transcranial magnetic stimulation. Functional magnetic resonance imaging demonstrated that the signal most proportional to subjective craving was located in the medial orbitofrontal cortex across all contexts, whereas the DLPFC most strongly encoded intertemporal availability information. The craving-related signal in the medial orbitofrontal cortex was attenuated by inactivation of the DLPFC, particularly when cigarettes were immediately available. Inactivation of the DLPFC also reduced craving-related signals in the anterior cingulate and ventral striatum, areas implicated in transforming value signals into action. These findings indicate that DLPFC builds up value signals based on knowledge of drug availability, and support a model wherein aberrant circuitry linking dorsolateral prefrontal and orbitofrontal cortices may underlie addiction.

Declarative memory disorders in patients with brain tumors can improve after cognitive training intervention: evidence from functional MRI

I read with great interest the recent paper published in Journal of Neuro-Oncology by Carlesimo [1]. The author proposed that declarative memory disorders in tumor patients could be identified even when the Papez circuit is not directly involved. It was suggested that attentional and executive impairments following frontal lobe involvement could produce these deficits because of disconnection of the frontal cortical areas from inputs arriving from other cortical and subcortical brain regions including the Papez circuit. The author also suggested that, although failure of the storage mechanisms generally precludes restorative interventions, deficits in the attentional, executive, and working memory mechanisms underlying encoding of information and the strategic retrieval of stored information can ‘‘likely’’ be re-educated and lead to improved declarative memory functioning. We have just published a study showing evidence of this hypothesis in tumor patients [2]. In this study, the brain correlates of strategic memory training were investigated in patients with primary tumors in the prefrontal cortex (PFC) using functional magnetic resonance imaging (fMRI) and cognitive tests. Twenty-one adult patients with postoperative lesions in the PFC (oligodendrogliomas, astrocytomas, meningiomas), 12 in the left dorsolateral PFC (LPFC) and 9 in the bilateral orbitofrontal cortex (BOFC), at least 6 months after surgery, were assessed before and after semantic strategy training using a verbal memory encoding paradigm during fMRI scanning. We used a within-subject design with no healthy controls. After cognitive training, both groups of patients showed significant improvement in declarative episodic verbal memory and use of semantic strategy. In the LPFC group, greater activity in left inferior and medial frontal gyrus (perilesional areas), precentral gyrus, and insula was found after training. For the BOFC group, higher activation was found in the left parietal cortex, right cingulate, and precuneus after training (new brain areas outside the usual episodic memory network). The activation of these specific areas within the memory and executive networks including perilesional and new brain areas following cognitive training was associated with compensatory brain mechanisms [3]. To our knowledge, this was the first description of patients with declarative memory disorders following PFC primary brain tumor lesions showing improvement in declarative memory after cognitive training associated with compensatory brain mechanisms. These findings corroborate the hypothesis described in Carlesimo’s article [1] of possible improvement and benefit from strategic memory training in patients with declarative episodic memory impairments due to cerebral tumors. Since a high prevalence of memory deficits is found in patients with cerebral tumors related to the effects of tumor mass, edema or as result of surgical, chemotherapy, and radiotherapy treatments, cognitive rehabilitation interventions could be of great value in management of such patients.

Significance of seizure in cerebral venous sinus thrombosis

PurposeTo report the frequency and predictors of presenting seizures in cerebral venous sinus thrombosis (CVST) and their influence on seizure recurrence and outcome. MethodsThis retrospective study, between 1995 and 2011, included 90 consecutive patients with CVST diagnosed using magnetic resonance imaging (MRI) and magnetic resonance venography (MRV). Clinical parameters like frequency, type (presenting, early, and late), and duration of seizures, precipitating causes of CVST, and underlying prothrombotic conditions, were recorded. The location of infarction on MRI and the number of sinuses involved on MRV, were noted. The patients were prescribed anticoagulants, and those with seizures were prescribed antiepileptic drugs. The patients were followed up at 3, 6, and 12months. The functional outcome at 6months was categorized into death, poor, partial and complete recovery. ResultsA total of 42 patients with CVST presented with seizures (focal 11, focal with secondary generalized 19, and generalized tonic clonic 16), of whom 10 had status epilepticus. On univariate analysis, supratentorial lesion (P=0.005), frontal (P=0.02) or parietal lobe (P=0.04) involvement and haemorrhagic lesion (P=0.002) were associated with higher risk of presenting seizure. On multivariate analysis, only supratentorial parenchymal lesion on MRI (odds ratio [OR]=4.67, 95% confidence interval [CI] 1.51–15.08, P=0.005) was independently associated with higher risk of presenting seizure. Only 4 patients had early seizures and none had late seizures. At 6months, 10 patients died and 73 patients had complete recovery. Seizures were not associated with death (P=1.00) and 6-month functional outcome (P=0.66). ConclusionAbout half the patients with CVST had presenting seizures which was independently related to supratentorial lesion. However, seizures were not related to death or 6-month outcome.

A Functional Near-Infrared Spectroscopy Study of Lexical Decision Task Supports the Dual Route Model and the Phonological Deficit Theory of Dyslexia

The dual route model (DRM) of reading suggests two routes of reading development: the phonological and the orthographic routes. It was proposed that although the two routes are active in the process of reading; the first is more involved at the initial stages of reading acquisition, whereas the latter needs more reading training to mature. A number of studies have shown that deficient phonological processing is a core deficit in developmental dyslexia. According to the DRM, when the Lexical Decision Task (LDT) is performed, the orthographic route should also be involved when decoding words, whereas it is clear that when decoding pseudowords the phonological route should be activated. Previous functional near-infrared spectroscopy (fNIR) studies have suggested that the upper left frontal lobe is involved in decision making in the LDT. The current study used fNIR to compare left frontal lobe activity during LDT performance among three reading-level groups: 12-year-old children, young adult dyslexic readers, and young adult typical readers. Compared to typical readers, the children demonstrated lower activity under the word condition only, whereas the dyslexic readers showed lower activity under the pseudoword condition only. The results provide evidence for upper left frontal lobe involvement in LDT and support the DRM and the phonological deficit theory of dyslexia.

Autosomal Dominant Alzheimer's Disease with Early Frontal Lobe Involvement Associated with the Met239Ile Mutation of Presenilin 2 Gene

Mutations in the Presenilin 2 gene (PSEN2) represent the less frequent genetic cause of familial Alzheimer's disease (FAD). Only eight PSEN2 mutations, reported in approximately 27 families, satisfied strict criteria of pathogenicity. We reported a patient with early-onset FAD and the PSEN2 p.Met239Ile mutation, presenting with severe executive dysfunction and myoclonic tremor, associated with memory loss. Brain SPECT study showed an early hypoperfusion of the frontal cortex. We confirmed the pathogenicity of PSEN2 p.Met239Ile mutation and its heterogeneous phenotypic expression. The modulating effect of the Apolipoprotein E and Prion Protein gene polymorphisms on the phenotypic variability was not confirmed.

Re-Engineering the Subthalamus

This historical vignette of the region known as “subthalamus” is timely and brings up how our current concepts regarding this region have evolved into the current level of high clinical importance for clinical treatment schemes. This pertinent review of older literature (particularly prior to 1990) highlights how previous concepts as to functioning and treatment in this region have been redefined and improved (1). Whereas most efforts at treatment of this region are now focused on motor disorders (ie, tremor and Parkinson’s disease) this vignette outlines the wide variety of other disorders once considered as involving the subthalamus, including epilepsy (16), chronic pain, and behavioral disorders, as neurosurgeons experimented to define the function of this region. Additionally, the authors include previous treatment paradigms (ie, various forms of lesioning, the previous mainstay of generating a treatment effect), now mostly supplanted by long-term electrical stimulation with deep brain stimulation (DBS), gene therapy approaches to modify long-term cellular function, and other biological or cellular treatments, all focused on augmentation of function rather than lesioning.

176 Intravascular B cell lymphoma: a case series

Intravascular B cell lymphoma is a rare subtype of diffuse large B cell lymphoma. Proliferation of lymphoma cells in small blood vessels causes occlusion. Four cases are presented. Cases 1...

Comment: Frontal lobes, executive dysfunction, gait and the fallacy of Pseudo-transitivity

Freezing of gait (FOG) in patients with Parkinson disease (PD) is particularly vexing as it causes disability and yet is often treatment refractory. Further, gait disorders do not track with volitional motor control. For example, gait often worsens with high-frequency deep brain stimulation while upper extremity function improves. Frontal lobes lesions can produce Bruns ataxia, an apraxia restricted to gait. Frontal lobe involvement in gait is further substantiated for PD by the findings of Kostic et …

Contributions of frontal and medial temporal lobe functioning to the errorless learning advantage

Among individuals with episodic memory impairments, trial-and-error learning is less successful than when errors are avoided. This “errorless learning advantage” has been replicated numerous times, but its neurocognitive mechanism is uncertain, with existing evidence pointing to both medial temporal lobe (MTL) and frontal lobe (FL) involvement. To test the relative contribution of MTL and FL functioning to the errorless learning advantage, 51 healthy older adults were pre-experimentally assigned to one of four groups based on their neuropsychological test performance: Low MTL-Low FL, Low MTL-High FL, High MTL-Low FL, High MTL-High FL. Participants learned two word lists under errorless learning conditions, and two word lists under errorful learning conditions, and memory was tested via free recall, cued recall, and source recognition. Performance on all three tests was better for those with High relative to Low MTL functioning. An errorless learning advantage was found in free and cued recall, in cued recall marginally more so for those with Low than High MTL functioning. Participants with Low MTL functioning were also more likely to misclassify learning errors as target words. Overall, these results are consistent with a MTL locus of the errorless learning advantage. The results are discussed in terms of the multi-componential nature of neuropsychological tests and the impact of demographic and mood variables on cognitive functioning.

Alveolar soft part sarcoma of the frontal calvarium and adjacent frontal lobe

Alveolar soft part sarcoma is a rare tumor affecting mainly adolescent and young children. It presents as a slowly growing tumor and is usually overlooked due to lack of symptoms. Early metastasis is a characteristic feature of this tumor and, in a good number of cases, metastasis to the lung or brain is the first manifestation of the disease. In this report, we present a case of alveolar soft part sarcoma predominantly located in the right frontal bone with dural breach and contiguous right frontal lobe involvement in a 17-year-old girl without any evident primary or other secondaries. A brief review of literature is also presented.

Anaplastic supratentorial cortical ependymoma presenting as a butterfly lesion

Background:Anaplastic cortical ependymomas are rare lesions with few cases reported in the literature.Case Description:We present a unique case of an anaplastic cortical ependymoma in a 51-year-old female presenting as a butterfly lesion with involvement of both frontal lobes. The patient underwent gross total resection of her tumor with further adjuvant treatment. We present the findings in our case and review the literature surrounding supratentorial ependymomas and their treatment outcomes.Conclusion:Rarely, cortical ependymoma can present as a butterfly lesion and should be considered in the differential diagnosis of such lesions in adults.

Acute Infantile Encephalopathy Predominantly Affecting the Frontal Lobes (AIEF)

Acute Infantile Encephalopathy Predominantly Affecting the Frontal Lobes (AIEF) is a relatively recent described entity. This article includes case reports of two patients who had bifrontal involvement during acute febrile encephalopathy. Case 1 describes a 1-y-old boy who presented with hyperpyrexia and dialeptic seizures. Imaging revealed significant bilateral frontal lobe involvement while serology proved presence of Influenza B infection. Over a period of onewk, he recovered with significant cognitive decline and perseveratory behavior. Another 6-y-old boy presented with language and behavioral problems suggestive of frontal dysfunction after recovering from prolonged impairment of consciousness following a convulsive status epilepticus. Bilateral superior frontal lesions with gyral swelling was evident on neuroimaging. These cases are among the very few cases of AIEF described in recent literature and the article also reviews this unique subtype of acute encephalopathy.

Frontal Lobe Involvement in Face Discrimination

Frontal Lobe Involvement in Face Discrimination

Temporal and Pontine Involvement in a Case of Herpes Simplex Encephalitis, Presenting as Kluver Bucy Syndrome - A Case Report

Bilateral temporal and frontal lobe involvement is a common characteristic of herpes simplex encephalitis (HSE). Clinical sequelae of herpes simplex encephalitis may manifest sometimes as Kluver Bucy syndrome (KBS). In herpes simplex encephalitis, apart from frontal lobe, extra temporal involvement is rare and uncommon. We report a case of HSE manifesting clinically as KBS with a rare radiological finding of temporal and extratemporal involvement of pons.

Clinicopathological correlations in corticobasal degeneration

To characterize cognitive and behavioral features, physical findings, and brain atrophy patterns in pathology-proven corticobasal degeneration (CBD) and corticobasal syndrome (CBS) with known histopathology. We reviewed clinical and magnetic resonance imaging data in all patients evaluated at our center with either an autopsy diagnosis of CBD (n = 18) or clinical CBS at first presentation with known histopathology (n = 40). Atrophy patterns were compared using voxel-based morphometry. CBD was associated with 4 clinical syndromes: progressive nonfluent aphasia (n = 5), behavioral variant frontotemporal dementia (n = 5), executive-motor (n = 7), and posterior cortical atrophy (n = 1). Behavioral or cognitive problems were the initial symptoms in 15 of 18 patients; less than half exhibited early motor findings. Compared to controls, CBD patients showed atrophy in dorsal prefrontal and perirolandic cortex, striatum, and brainstem (p < 0.001 uncorrected). The most common pathologic substrates for clinical CBS were CBD (35%), Alzheimer disease (AD, 23%), progressive supranuclear palsy (13%), and frontotemporal lobar degeneration (FTLD) with TDP inclusions (13%). CBS was associated with perirolandic atrophy irrespective of underlying pathology. In CBS due to FTLD (tau or TDP), atrophy extended into prefrontal cortex, striatum, and brainstem, whereas in CBS due to AD, atrophy extended into temporoparietal cortex and precuneus (p < 0.001 uncorrected). Frontal lobe involvement is characteristic of CBD, and in many patients frontal, not parietal or basal ganglia, symptoms dominate early stage disease. CBS is driven by medial perirolandic dysfunction, but this anatomy is not specific to a single underlying histopathology. Antemortem prediction of CBD will remain challenging until clinical features of CBD are redefined, and sensitive, specific biomarkers are identified.

Central nervous system pathology in fatal swine-origin influenza A H1N1 virus infection in patients with and without neurological symptoms: an autopsy study of 15 cases

The first influenza pandemic of the twenty-first century was caused by a swine-origin, influenza A (H1N1) virus that contained genes from human, swine, and avian influenza A viruses [4]. It has long been recognized that a small subset of influenza patients develops neurologic complications [1]. Central nervous system (CNS) pathology in influenza virus infection is thought to be indirect and multifactorial [15] and whether H1N1 infects the brain or cerebrospinal fluid (CSF) remains controversial [2]. The current model is that H1N1 triggers a cytokine storm that disrupts the blood–brain barrier and activates glial cells. Subsequent disseminated intravascular coagulation (DIC) and liver and renal dysfunction triggered by hypercytokinemia may also contribute to CNS damage [15]. A number of clinical syndromes affecting the CNS have been described in the context of influenza infection. Although these syndromes have overlapping features and can be caused by other viruses and toxic agents, they have specific clinical, radiological, and laboratory criteria for their diagnosis and the pathogenesis and predisposing factors differ. Classical Reye’s syndrome is a non-inflammatory encephalopathy with associated hepatic microvesicular fatty change and hyperammonemia, and is usually precipitated by the use of salicylates [5]. Reye’slike syndrome occurs at a younger age and does not have the microvesicular fatty change and mitochondrial abnormality of classical Reye’s syndrome [13] and it is not associated with salicylate use. Hemorrhagic shock and encephalopathy syndrome (HSES) occurs in infants, and there is associated fever, shock, DIC, hepatic and renal dysfunction, and the brain shows edema with occasional intracranial hemorrhage [3]. Acute necrotizing encephalopathy (ANE) was first described in Japan in 1995 [8], and then subsequently in other countries [7, 16]. MRI and autopsy studies show bilateral symmetrical infarcts in the thalamus, basal ganglia, cerebellar and cerebral white matter, and brainstem tegmentum. CSF protein is typically elevated and the mortality rate is high. Some infants have complex febrile seizures at the onset, followed by delayed involvement of bilateral frontal lobes or the entire cerebral hemisphere [12]. Recently, familial and recurrent ANE has been described and is associated with mutation in the Ranbinding protein gene (RANBP2) [10]. Like earlier influenza pandemics, the recent pandemic of novel influenza A (H1N1) infection has resulted in a number of cases with neurological complications [2, 7, 16]. The purpose of the present study was to document the changes present in the brains of fatal H1N1 virus patients to determine if cases without documented neurologic A. Mukherjee and J.E.G. Peterson contributed equally to this work.

Behavioral changes in early ALS correlate with voxel-based morphometry and diffusion tensor imaging

Amyotrophic lateral sclerosis (ALS) is a multisystem disorder with impairment of frontotemporal functions such as cognition and behavior, but the behavioral changes associated with ALS are not well defined. Twenty-one consecutive patients with sporadic ALS and 21 control subjects participated in the study. The Frontal System Behavior Scale (FrSBe) was used to assess behavioral change. Voxel-based morphometry (VBM) and voxel-based analysis of diffusion tensor images (DTI) were performed to explore the associations of brain degeneration with behavior. All patients were evaluated before the notification of ALS. FrSBe scores of ALS patients before notification were significantly increased compared to those of control subjects. Moreover, the FrSBe Apathy score of ALS patients significantly changed from pre- to post-illness (P<0.001). The severity of apathy was significantly correlated with atrophy in the prefrontal cortex, especially in the orbitofrontal (P=0.006) and dorsolateral prefrontal (P=0.006) cortices in VBM, and in the right frontal gyrus (P<0.001) in DTI. ALS patients exhibited apathy during the early course of the illness, the severity of which was significantly associated with frontal lobe involvement. These findings support the view that a continuum exits between ALS and frontotemporal dementia.

Cognitive and neuroimaging profile of a Brazilian family with CADASIL

Cerebral autosomal dominant arteriopathy with subcortical infarcts and leukoencephalopathy (CADASIL) is an inherited small vessel disease leading to small infarcts and subcortical vascular dementia. This study presents results from the neuropsychological and neuroimaging evaluation of functionally autonomous individuals of a Brazilian family with CADASIL. The causal mutation was confirmed in four family members. Seven individuals from two generations were evaluated using the CERAD battery and additional neuropsychological tests and were submitted (6 individuals) to magnetic resonance imaging (MRI) of the brain with specific protocols for white matter lesion quantification. Apraxic changes and fast progression over nine months (neuropsychological reevaluation of 6 individuals) were found in many individuals. The MRI study suggests greater involvement of frontal lobes in more severely affected individuals. Even functionally independent individuals may exhibit significant neuropsychological and neuroimaging changes. Apraxia, little commented on in literature, and rapidly progressive cognitive changes were found in this group.

Hippocampal activation correlates with visual confrontation naming: fMRI findings in controls and patients with temporal lobe epilepsy

SummaryPurposeIn patients with left temporal lobe epilepsy (TLE) due to hippocampal sclerosis (HS) decreased naming ability is common, suggesting a critical role for the medial left temporal lobe in this task. We investigated the integrity of language networks with functional MRI (fMRI) in controls and TLE patients.Experimental designWe performed an fMRI verbal fluency paradigm in 22 controls and 66 patients with unilateral mesial TLE (37 left HS, 29 right HS). Verbal fluency and naming ability were investigated as part of the standard presurgical neuropsychological assessment. Naming ability was assessed using a visual confrontation naming test.ResultsLeft TLE patients had significantly lower naming scores than controls and those with right TLE. Right TLE patients performed less well than controls, but better than those with left TLE. Left TLE had significantly lower scores for verbal fluency than controls.In controls and right TLE, left hippocampal activation during the verbal fluency task was significantly correlated with naming, characterised by higher scores in subjects with greater hippocampal fMRI activation. In left TLE no correlation with naming scores was seen in the left hippocampus, but there was a significant correlation in the left middle and inferior frontal gyri, not observed in controls and right TLE. In left and right TLE, out of scanner verbal fluency scores significantly correlated with fMRI activation for verbal fluency in the left middle and inferior frontal gyri.ConclusionGood confrontation naming ability depends on the integrity of the hippocampus and the connecting fronto-temporal networks. Functional MRI activation in the left hippocampus during verbal fluency is associated with naming function in healthy controls and patients with right TLE. In left TLE, there was evidence of involvement of the left frontal lobe when naming was more proficient, most likely reflecting a compensatory response due to the ongoing epileptic activity and/or underlying pathology.