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Abstract Due to extensive connectivity of the parietal lobe, non‐lesional drug‐resistant (DRE) parietal lobe epilepsies (PLEs) are difficult to localize and often imitate other epilepsies. Therefore, patients with PLEs have low rates of seizure freedom following epilepsy surgery. Previous studies have highlighted the need to combine EEG and semiology for more accurate localization of PLEs. As sophisticated tools for localization become more available, the use of multiple different neuroimaging and neurophysiologic diagnostic tests may more readily identify PLE. We hereby report a unique case of a complex localization in a non‐lesional PLE, which was initially falsely localized to frontal lobe. This case underscores the utility of voxel‐based morphometry (VBM) in identifying an epileptogenic lesion on a non‐lesional MRI and the significance of multimodality approach including PET, magnetoencephalopathy (MEG), interictal and ictal EEG, semiology and cortical stimulation for accurate localization of PLEs. Understanding epilepsy through multimodality approach in this fashion can help with accurate localization especially in difficulty to localize and deceptive non‐lesional PLEs. Plain Language Summary Parietal lobe epilepsies are hard to pinpoint in the brain and can mimic other types of epilepsy, especially when brain MRIs appear normal. As sophisticated tools for locating epilepsies in the brain become more available, using multiple diagnostic tests may help identify parietal lobe epilepsies more easily. We describe a unique case of a parietal lobe epilepsy patient with normal brain MRI whose epilepsy was initially misidentified as being in the frontal lobe. Using various advanced diagnostic tests, we accurately found the epilepsy's true location in the parietal lobe and successfully treated the patient with surgery.

Due to extensive connectivity of the parietal lobe, non‐lesional drug‐resistant (DRE) parietal lobe epilepsies (PLEs) are difficult to localize and often imitate other epilepsies. Therefore, patients with PLEs have low rates of seizure freedom following epilepsy surgery. Previous studies have highlighted the need to combine EEG and semiology for more accurate localization of PLEs. As sophisticated tools for localization become more available, the use of multiple different neuroimaging and neurophysiologic diagnostic tests may more readily identify PLE. We hereby report a unique case of a complex localization in a non‐lesional PLE, which was initially falsely localized to frontal lobe. This case underscores the utility of voxel‐based morphometry (VBM) in identifying an epileptogenic lesion on a non‐lesional MRI and the significance of multimodality approach including PET, magnetoencephalopathy (MEG), interictal and ictal EEG, semiology and cortical stimulation for accurate localization of PLEs. Understanding epilepsy through multimodality approach in this fashion can help with accurate localization especially in difficulty to localize and deceptive non‐lesional PLEs. Plain Language Summary: Parietal lobe epilepsies are hard to pinpoint in the brain and can mimic other types of epilepsy, especially when brain MRIs appear normal. As sophisticated tools for locating epilepsies in the brain become more available, using multiple diagnostic tests may help identify parietal lobe epilepsies more easily. We describe a unique case of a parietal lobe epilepsy patient with normal brain MRI whose epilepsy was initially misidentified as being in the frontal lobe. Using various advanced diagnostic tests, we accurately found the epilepsy's true location in the parietal lobe and successfully treated the patient with surgery. [ABSTRACT FROM AUTHOR]

The purpose of this review is to describe the functional anatomy of the precuneal cortex and outline some semiological features of precuneal seizures. The precuneal cortex is a structure that occupies the posterior medial portion of the parietal lobe, and it has broad cortical and subcortical connections. Neuroanatomical tracing, functional imaging, as well as electrical stimulation studies of humans and other primates have elucidated many complex integrative functions of the precuneus including visuo-spatial imagery, sensorimotor functions, and consciousness. Based on the understanding of its functions and connectivity, descriptions of potential seizure semiologies are hypothesized and compared to what is available in the literature. The latter is mostly in the form of case reports or case series. Seizures may involve simple or complex motor or sensory manifestations including abnormal eye movements, visual hallucinations, sensation of motion, or medial temporal-like seizures.

Some surgical failures after temporal lobe epilepsy surgery may be due to the presence of an extratemporal epileptogenic zone. Of particular interest is the medial parietal lobe due to its robust connectivity with mesial temporal structures. Seizures in that area may be clinically silent before propagating to the symptomatogenic temporal lobe. In this paper, we present an overview of the anatomical connectivity, semiology, radiology, electroencephalography, neuropsychology, and outcomes in medial parietal lobe epilepsy. We also present two illustrative cases of seizures originating from the precuneus and the posterior cingulate cortex. We conclude that the medial parietal lobe should be strongly considered for sampling by intracranial electrodes in individuals with nonlesional temporal lobe epilepsy, especially if scrutinizing the presurgical data produces discordant findings. [ABSTRACT FROM AUTHOR]

Some surgical failures after temporal lobe epilepsy surgery may be due to the presence of an extratemporal epileptogenic zone. Of particular interest is the medial parietal lobe due to its robust connectivity with mesial temporal structures. Seizures in that area may be clinically silent before propagating to the symptomatogenic temporal lobe. In this paper, we present an overview of the anatomical connectivity, semiology, radiology, electroencephalography, neuropsychology, and outcomes in medial parietal lobe epilepsy. We also present two illustrative cases of seizures originating from the precuneus and the posterior cingulate cortex. We conclude that the medial parietal lobe should be strongly considered for sampling by intracranial electrodes in individuals with nonlesional temporal lobe epilepsy, especially if scrutinizing the presurgical data produces discordant findings.

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Copyright of Zeitschrift für Epileptologie is the property of Springer Nature and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Objective The precuneus is a complex and highly connected structure located in the medial portion of the superior parietal lobule. The clinical presentation of precuneal epilepsy is poorly characterized, mostly because these patients have seldom been distinguished from those with other types of parietal lobe epilepsy. The present study aims to improve the understanding of precuneal epilepsy by detailing its clinical features and surgical outcomes. Methods Six previously unreported cases of drug-resistant precuneal epilepsy investigated between 2002 and 2014 were retrospectively studied. Seizure focus was confirmed by presence of a lesion, intracranial monitoring, or post-operative seizure control when applicable. Results Seizures arising from the precuneus have heterogeneous presentations, including body movement sensation, visual auras, eye movements, vestibular manifestations, and complex motor behaviors. Two patients with an anterior precuneus lesion described body movement sensations whereas two others with a posterior precuneus lesion experienced visual symptoms. Two of the five patients who underwent epilepsy surgery achieved good seizure control (Engel IA). One patient underwent gamma knife surgery with an Engel IV outcome. Surgical complications included contralateral visual field impairment, limb hypoesthesia and hemispatial neglect. One patient developed late-onset epilepsia partialis continua from a Rolandic subdural grid-related contusion. Significance In absence of a clear precuneal epileptogenic lesion, recognition of a precuneal focus is challenging. Magnetoencephalography may sometimes localize the generator but invasive EEG remains in well-selected cases necessary to identify the seizure focus. Surgical failures may be explained by the widespread connectivity of the precuneus with distant and adjacent structures. Different ictal manifestations of precuneal epilepsy in this series provide a clinical correlate to the described functional subdivisions of the precuneus. [ABSTRACT FROM AUTHOR]

Objectives: Parietal lobe epilepsy is one of the rarest types and patients with this form of epilepsy report multiple subjective symptoms during ictal manifestation. Specific facial coupling of emotion and motor symptoms may take various forms, such as pouting and disgust or smiling. We aimed to highlight brain structures and the network involved during ictal grimacing in parietal lobe seizures., Methods: In this study, we report two patients with drug-resistant epilepsy, with seizure onset located in the inferior parietal lobule and a semiology characterized by ictal grimacing. Patients were explored with intracranial electrodes using the stereo-electroencephalographic method. Time-frequency and functional connectivity (a non-linear regression method based on the h² correlation coefficient) signal analyses were performed time-locked to ictal grimace. For both patients, using spectral analysis, we were able to confirm that the bipolar channels, localized at the level of the inferior parietal lobule, were involved in the seizure onset zone, exhibiting a high frequency discharge., Results: The first patient presented with ictal pouting and disgust and the second with smiling/laughter. Connectivity analysis highlighted two different networks responsible for seizure semiology, consisting of grimacing with different emotional expression. The inferior parietal lobule, connected mainly to the anterior insula, dorsal-lateral prefrontal cortex and frontal operculum were responsible for the typical grimace associated with disgust. Furthermore, the inferior parietal lobule, basal temporal structures, superior temporal gyrus, orbitofrontal cortex and temporal pole were involved in smiling and laughter., Significance: It is of great significance for epileptologists to know that the same seizure onset zone in the inferior parietal lobule can generate contrasting facial expressions, smiling/laughter and pouting/disgust, by engaging different epileptogenic networks; the temporo-basal-orbitofrontal and insulo-opercular networks, respectively.

Summary Supernumerary phantom limbs, that is, the awareness of an illusory extra limb is a fascinating neurologic symptom that has been described in a number of neurologic diseases including stroke, spinal injury, and epilepsy. Herein we report a case of a 70-year-old male patient with new-onset focal seizures with left-sided supernumerary phantom arm and leg as the only seizure manifestation. Ictal single-photon emission computed tomography (SPECT) revealed a hyperperfusion in the right temporoparietal junction and allowed localization of the seizure-onset zone. This report is accompanied by a discussion of phenomenology and terminology in the context of existing literature. [ABSTRACT FROM AUTHOR]

This study evaluated pre- and postoperatively cognitive functions in 15 pediatric patients with surgically treated parietal lobe epilepsy (PLE). Seizure outcome was very satisfying with 87% seizure-free patients 1 year after surgery, and 82% in the long-term follow-up. Preoperative intelligence was in the subaverage range. Impairments in specific cognitive functions (memory, attention, executive functions) were evident preoperatively for 39–66% of patients. Behavioral disorders were rare. No side differences (left versus right PLE) were indicated pre- or postoperatively. Postoperative improvements were found in behavior and attention; other cognitive functions were unchanged. All in all, this preliminary study indicated a satisfactory neuropsychological outcome in pediatric patients with PLE. [ABSTRACT FROM AUTHOR]

Summary: Introduction: To analyze the diagnostic accuracy of MRI in patients undergoing parietal and occipital lobe epilepsy surgery. Methods: In a retrospective study, we analyzed MRI scans and neuropathology reports of 42 patients who had undergone resective epilepsy surgery in the parietal and occipital lobe between 1998 and 2003. We evaluated, whether lesions were precisely characterized by MRI and whether lesion characterization allowed to estimate postsurgical seizure outcome. Results: Within the categories epilepsy associated tumors, focal cortical dysplasias, vascular malformations, scarring, and others, MRI was concordant with histopathology in 36 of 42 (86%) lesions. Among the discordant lesions, one lesion was re-classified following MRI–histopathology synopsis, another two lesions represented new tumor entities (angiocentric neuroepithelial tumor, isomorphic astrocytoma) which have been described recently. Seizure freedom (Engel class I) one year following surgery was achieved in 25 patients (60%). Seizure outcome was different for lesion categories (Engel class I: epilepsy associated tumors, 62%; focal cortical dysplasias, 71%; vascular malformations, 75%; scarring, 40%), and was unchanged if no lesion was found on preoperative MRI. Conclusion: If MRI and histopathology are discordant, not only the MRI findings may be debatable. MRI lesion detection is important, since chance of seizure freedom is low if no lesion is detected. [Copyright &y& Elsevier]

Purpose: To characterize the clinical features, the prognostic value, and diagnostic sensitivities of various presurgical evaluations and the surgical outcomes in parietal lobe epilepsy (PLE), we describe 40 patients who were diagnosed as having PLE, including 27 surgically treated patients. Methods: The diagnosis was established by means of a standard presurgical evaluation, including magnetic resonance imaging (MRI), fluorodeoxyglucose–positron emission tomography (FDG-PET), ictal single-photon emission tomography (SPECT), and scalp video-electroencephalography (EEG) monitoring, with additional intracranial EEG monitoring in selected cases. Results: Among the 40 patients, 27 experienced at least one type of aura. The most common auras were somatosensory (13 patients), followed by affective, vertiginous, and visual auras. The patients had diverse manifestations. Eighteen patients showed simple motor seizure, followed by automotor seizure, and dialeptic seizure. Two patients manifested generalized tonic–clonic seizures only, and 19 patients experienced more than one type of seizure. The surgical outcome was favorable in 22 of 26 patients including 14 who were seizure free. Patients with localized MRI abnormality had a higher probability to be seizure free, with marginal significance (p = 0.062), whereas other diagnostic modalities failed to predict the surgical outcome. In the seizure-free group, localization sensitivity was 64.3% by MRI, 50% by PET, 45.5% by ictal SPECT, and 35.7% by ictal EEG. The concordance rate of the various diagnostic modalities was higher in the seizure-free group than in the non–seizure-free group, although it did not reach statistical significance. Conclusions: Seizures, in the case of PLE, can manifest themselves in a wider variety of ways than was previously thought. Surgical outcome was favorable in most of the patients. MRI abnormality and concordance of different diagnostic modalities were associated with high seizure-free rate. [ABSTRACT FROM AUTHOR]

Summary: Purpose: To analyze the semiology of seizure onset and evolution in young children with posterior cortex epilepsy (PCE), compare this with adult reports, and assess age-related differences. Methods: We videotaped and analyzed 110 seizures from 18 patients with PCE, aged 3–81 months. All had a good prognosis after posterior epileptogenic zone removal. Ictal events were categorized by behavioral, consciousness, autonomic, and sensory features, as well as motor patterns, which included myoclonic, tonic, clonic, unclassified motor seizures, and epileptic spasm. A time-scaled data sheet was developed to record each epileptic event as onset, very early, early, or late manifestation. Results: Patients had a high seizure frequency with ≤100 attacks/day; one third of them showed a cluster tendency. The mean duration of seizures was 67 s. The most common seizure components were motor manifestations (with myoclonic and tonic seizures), but psychomotor (automotor), hypomotor attacks, and isolated auras also were frequently observed. Clinical seizure spread was frequent; auras and visual sensory signs were difficult to record in this age. Typical phenomena during seizures included behavioral changes, ictal vocalization, smile, flush, head nod, oculomotor features, and late-appearing oral automatisms, whereas hypermotor and secondarily generalized tonic–clonic seizures were not seen. Conclusions: Our results suggest that PCE in infants and young children is very heterogeneous but shows important age-related features. Compared with adults, children with PCE have shorter but more frequent seizures; they rarely report aura or visual sensory signs, only sporadically develop hypermotor and secondarily generalized tonic–clonic seizures, whereas ictal smile, flush, head nod, and behavioral change are typical features at this age. Because of frequent subtle ictal phenomena, long-term video-EEG monitoring is a useful diagnostic tool with infants... [ABSTRACT FROM AUTHOR]

Due to a limited number of patients with drug-resistant parietal lobe epilepsy in surgical series, there are insufficient data about long-term seizure outcome following surgery restricted to the parietal lobe. We performed a meta-analysis to asses long-term outcomes in patients with parietal lobe epilepsy who underwent surgery confined to the parietal lobe or resection with major involvement of the parietal cortex. An English language literature search for studies on parietal lobe surgery and outcome was conducted using the MEDLINE database, followed by a manual search based on specific criteria. An inverse variance random effect meta-analysis model was used to estimate the pooled proportion of Engel Class I. Meta-regression models were used to examine the association between outcome and potential predictors. The search yielded seven retrospective studies with a total sample size of 253 patients (mean follow-up: 104.9±74.8 months). Following surgery, Engel Class I surgical outcome was achieved in 62.4% (95% CI: 0.492-0.755). Two independent predictors were identified for positive long-term outcome: interictal EEG localized to the parietal region (p=0.007) and the presence of tumour (p=0.022). Following surgery confined to the parietal lobe or resection with major involvement of the parietal cortex, the long-term prognosis of patients with parietal lobe epilepsy is favourable.

Background: Increased production of cell-free DNA (cf-DNA), a marker of inflammation, cell death and degeneration, has been observed in stroke and severe traumatic brain injury among other medical conditions. The purpose of the present study was to evaluate the significance of cf-DNA in patients with focal epilepsy., Methods: cf-DNA was measured in 167 consecutive well-evaluated patients with focal epilepsy (147 with refractory epilepsy). Epilepsy was characterized based on the patient history, electroclinical findings, neuroimaging results and etiology. 250 healthy individuals served as control subjects., Results: The majority of the patients (125/167; 74.8%) had increased concentrations of cf-DNA. The median concentration of cf-DNA was significantly higher in the patients (0.867 μg/ml) compared to the control group (0.759 μg/ml) (p<0.001). Symptomatic etiology was associated with increased concentrations of cf-DNA compared to probably symptomatic etiology (p=0.036)., Conclusions: The study confirms that the release of cf-DNA is more active in symptomatic refractory focal epilepsy, whereas this process is less pronounced in patients with unknown cause of epilepsy., (Copyright © 2013 Elsevier B.V. All rights reserved.)