Left Temporo-occipital Region Research Articles

Nonconvulsive status epilepticus manifesting as pure alexia (alexia without agraphia)

Pure alexia is a rare disorder usually caused by an ischemic or hemorrhagic stroke. We describe a case of pure alexia due to nonconvulsive status epilepticus (NCSE). This 57-year-old man presented in a hyperosmolar, nonketotic state with fluctuations in mental status and an inability to read. His EEG was diagnostic of NCSE originating from the left temporo-occipital region. MRI of the brain revealed increased FLAIR signal over the left occipitotemporal region. Following initiation of antiepileptic treatment, his neurological examination normalized concomitantly with resolution of the NCSE. A follow-up MRI scan of the brain obtained 1 month later was normal. NCSE can have unusual clinical manifestations, and a high index of suspicion is necessary to correctly diagnose these patients.

Gardner's syndrome: Genetic testing and colonoscopy are indicated in adolescents and young adults with cranial osteomas: A case report

We present a case of a 25-year-old female with diagnosed familial adenomatous polyposis and elevated carcinoembryonic antigen with negative family history. The suspicion of Gardner's syndrome was raised because extirpation of an osteoma of the left temporo-occipital region was made 10 years ago. Restorative procto-colectomy and ileal pouch anal anastomosis was made but histology delineated adenocarcinoma of the rectum (Dukes C stage). We conclude that cranial osteomas often precede gastrointestinal manifestations of familial adenomatous polyposis or Gardner's syndrome and such patients should be evaluated with genetic testing followed by colonoscopy if results are positive to prevent the development of colorectal carcinoma. If the diagnosis is positive all family members should be evaluated for familial adenomatous polyposis.

The Neuropsychiatry of Shamanism

The shamanic state is a human constant, arising from the substrate of the brain. Hunter-gatherer shamanism is based on altered states of consciousness, induced by a variety of means.This paper examines shamanism from a neuropsychiatric perspective, looking at disorders of self, hallucinations, epilepsy, schizophrenia and other psychoses, lycanthropy, and sleep disorders. While the majority of shamanic individuals are normal in that they do not have neuropsychiatric disorders, examination of these conditions can illustrate the underlying brain mechanisms.The speciation of Homo sapiens led to lateralisation of the brain with significant expansion in the left temporo-occipital region that allowed the use of symbolism. Laterality changes - decreased left/increased right hemisphere dominance - link schizophrenia, schizotypy and increased creativity. From this it was a short step to the phenomena intrinsic to shamanism.

Magnetic resonance imaging in occipital lobe epilepsy with frequent seizures

Magnetic resonance imaging and single-photon emission computed tomography provide useful information in the evaluation of the pathophysiology of epileptic foci. Ictal magnetic resonance imaging in a 7-year-old male with occipital lobe epilepsy revealed mild swelling of the left temporo-occipital region, with hyperintensity on T 2-weighted and fluid attenuated inversion recovery images. This lesion, however, was not detected on diffusion-weighted imaging. An ictal single-photon emission computed tomography study using 99mTc-ECD demonstrated left temporo-occipital hyperperfusion. T 2-weighted and fluid attenuated inversion recovery images revealed hyperintensity without atrophy 4 months after control of his seizures. The focus in nonconvulsive status epilepticus has been reported as showing hyperintensity on T 2-weighted, fluid attenuated inversion recovery and diffusion-weighted images. Since hyperintensity on diffusion-weighted imaging reflects cytotoxic intracellular edema due to excitotoxicity, and his ictal diffusion-weighted image exhibited no remarkable change, the lesions in the left temporo-occipital region resulted from vasogenic edema. Cytotoxic edema resulting from excitotoxicity leads to neuronal death, causing cortical atrophy. Thus, diffusion-weighted imaging is a useful tool to predict the prognosis of frequent seizures.

Síndrome de Parry-Romberg asociado a epilepsia refractaria, atrofia de la duramadre y leucoencefalopatía quística cerebral

We report the clinical and radiologic observation in a man patient of 20 years old. He developed gravity left progressive facial hemiatrophy. In associated form, he presented numerous visual sensories and complex partials seizures. The single and combined treatment with several antiepileptic drugs was ineffective for the control of the epilepsy. The magnetic resonance investigation of the cranium facial structures showed the gravity and intensivity of the dysmorphia. The same procedure showed the strong of the duramadre atrophy in the convexity of the brain, as well as, the existence of the cystic formation in the white matter of the left temporo occipital region at the face affected. We considered, that this is the first report documented fully, about the Parry Romberg syndrome with refractory epilepsy, duramadre atrophy and cystic leukoencephalopaty, published in Peru.

Event-related potential index of semantic mnemonic dysfunction in abstinent alcoholics

Background: The objective of the study was to expand the investigation of the match/mismatch mnemonic impairment in the semantic domain in sober alcoholics. Methods: Event-related potentials (ERPs) were recorded from 28 healthy adults and 36 sober alcoholics in a category (either animals or fruits/vegetables) match/nonmatch S1–S2 paradigm. Results: There was a significant interaction of ERP amplitude (c3) between groups (controls vs. alcoholics) and stimulus conditions (category match vs. nonmatch) at the posterior brain regions; the c3 component was smaller for the category match than for nonmatch trials in controls, with the absence of such c3 differences in alcoholics. There were no significant ERP differences between the two groups in processing the sample stimuli. The ERPs (c2) elicited by the animal category were larger than those for the vegetable category in both groups. The alcoholics showed prominent suppressed activation of left temporo-occipital brain regions under both matching and nonmatching conditions, as demonstrated by the current source density maps. The alcoholics were also slower and less accurate than the controls in judging both category matching and nonmatching stimuli, while neither of the two groups demonstrated shorter response times to the matching stimuli. Conclusions: These data suggest that alcoholics are less efficient in the semantic mnemonic match/nonmatch process, and are less likely to be deteriorated in the stage of forming the template for such match/nonmatch comparisons.

EEG Changes during Mental Activation

Desynchronization of the EEG in relation to mental activity can be demonstrated through various means. The acceleration spectrum entropy (ASE) is a method that quantifies the desynchronization of the EEG. It is a measure of the randomness or irregularity of a time series and ranges from 0 (straight line) to 100 (discrete random signal). The ASE was calculated for 20 EEGs under four conditions: "eyes closed," "eyes open," "eyes closed and mental arithmetic" and "eyes open and mental arithmetic." There was a significant increase between the conditions "eyes closed" and "eyes open" and a significant increase between the conditions "eyes closed" and "eyes closed and mental arithmetic." During eye opening the largest increase was seen in the occipital areas. Mental arithmetic showed an asymmetrical increase, namely in the left temporo-occipital region and in the right centro-temporal region. It is suggested that the ASE can be used to study cortical activation due to mental activity.

Neuronal migrational disorders: diffuse cortical dysplasia or the “double cortex” syndrome

We report a 10-year-old girl who presented with a single episode of partial complex seizure. Neurological examination and psychological evaluation were normal. Electroencephalogram showed abnormalities in the left temporo-occipital region. Magnetic resonance imaging revealed a bilateral layer of tissue iso-intense with gray matter, between the wall of the lateral ventricle and the cortex, extending from the frontal to the occipital region, and enlarged left lateral ventricle. The images indicated diffuse cortical dysplasia, also known as band heterotopia or "double cortex", and left cortical hemiatrophy.

Miosis and internal ophthalmoplegia as a manifestation of partial seizures

We present a patient whose only physical manifestation of a partial sensory seizure was bilateral pupillary constriction and internal ophthalmoplegia. The onset and offset of each attack corresponded distinctly with an electroencephalographic discharge of the left temporo-occipital region. We propose involvement of a cortical pupillary constrictive center in the temporal-occipital area.

Malignant Fibrous Histiocytoma of the Occipital Bone with Intracranial Extension

The authors present a rare case of malignant fibrous histiocytoma originating in the cranial bone. A 72-year-old male was admitted with a diffuse painless swelling in the left occipital region but no neurological abnormality. Plain skull x-ray films and computed tomographic scans showed a large tumor in the left temporo-occipital bone. The tumor invading subcutaneous tissue was totally excised and histologically diagnosed as malignant fibrous histiocytoma. Postoperatively, 40-Gy irradiation was given to the left temporo-occipital region. Several months later, however, the tumor recurred in the posterior fossa. Neuroradiological examination showed tumor extension into the occipital bone and muscle and the subdural space of the posterior fossa. A second operation extirpated all tumors except in the cerebellum. He died of pneumonia on the 14th postoperative day. Autopsy revealed malignant fibrous histiocytoma invading into the bilateral cerebellar hemispheres. Radiation and chemotherapy should be given as soon as possible following extensive surgery for malignant fibrous histiocytoma of the cranial bone.

The ability of patients with brain damage to generate mental visual images.

The ability to form mental visual images was investigated in normal controls, patients with localized brain damage, and patients with Parkinson's disease. Verbal and visuospatial imagery tasks were compared with tasks in the same modality that did not demand the formation of visual images. In the verbal part, memorizing of word pairs was tested for abstract words, concrete words without imagery instruction, and concrete words with imagery instruction. In the visuospatial part, three tests required the evaluation of spatial features of imagined letters. In one of them mental rotations had to be performed in the exploration of the imagined stimulus. The visuospatial control tasks tested the ability to judge the position of perceived dots and mentally to rotate a seen mannekin. The pattern of results was determined mainly by the differential sensitivity of visuospatial and verbal tasks to right and left brain damage, respectively. Multidimensional scaling of correlations between test results did not show a close relationship between the results of verbal and visuospatial imagery tasks, but suggested that brain damage affected visuospatial imagery tasks differentially from visuospatial control tasks. Analysis of single cases showed that patients with lesions of the left temporo-occipital region failed to benefit from the imagery instruction in the memorizing of concrete words. These patients could nonetheless solve correctly the visuospatial imagery tasks. Possibly this dissociation is due to differences in the amount or the quality of information conveyed by the visual images rather than to the verbal or visuospatial mode of processing to which the images are subjected.

Mitral Valve Prolapse

• A 30-year-old man was admitted to the hospital with a history of sudden onset of bizarre behavior and difficulty in speaking that initially was attributed to drug intoxication. Examination disclosed a confused young man with receptive and expressive aphasia. A late systolic murmur was heard in the mitral area and echocardiography confirmed the presence of mitral valve prolapse. A computed tomographic scan of the head and cerebral angiography showed abnormalities consistent with an infarct of the left temporo-occipital region. Since no other predisposing factors were present, this patient's stroke was probably related to mitral valve prolapse. (<i>Arch Intern Med</i>1982;142:1215-1216)

Mitral valve prolapse: association with bizarre behavior, a confusional state, and aphasia

A 30-year-old man was admitted to the hospital with a history of sudden onset of bizarre behavior and difficulty in speaking that initially was attributed to drug intoxication. Examination disclosed a confused young man with receptive and expressive aphasia. A late systolic murmur was heard in the mitral area and echocardiography confirmed the presence of mitral valve prolapse. A computed tomographic scan of the head and cerebral angiography showed abnormalities consistent with an infarct of the left temporo-occipital region. Since no other predisposing factors were present, this patient's stroke was probably related to mitral valve prolapse.

LXXXII. Brain Abscess of Otitic Origin in the Left Temporo-Occipital Region with All the Typical Symptoms. Operation. Recovery

LXXXII. Brain Abscess of Otitic Origin in the Left Temporo-Occipital Region with All the Typical Symptoms. Operation. Recovery