1/20. Surgery or gamma -knife for the treatment of arteriovenous malformations?decision making for either surgery or gamma-knife for the treatment of arteriovenous malformations (AVMs) cannot be uniform. The skill of the neurosurgeon in operating on AVMs is now being compared with that of the gamma-knife. The decision varies from case to case and is to be taken by the neurosurgeon. This report presents three cases in which such decision making was not easy. Case 1 was a non-ruptured cingulate AVM of 2.5 cm diameter in the cingulate cortex. The operative field was anticipated to be very narrow between the parietal bridging veins. Case 2 was a tiny ruptured AVM in the speech-motor area which was buried underneath the cortex. Case 3 was a large ruptured thalamo-stiriate-capsular AVM with feeders from the anterior and posterior choroidal arteries. All cases were operated without serious morbidity. A combination of pre-operative intravascular surgery (cases 1 and 3) or postoperative gamma-knife (case 3) was adopted. In conclusion, there is no unitary rule to decide on surgery or gamma-knife for the treatment of AVMs. It depends on what good or harm the responsible surgeon or the gamma-knife does.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
2/20. Surgical indications and microsurgical anatomy of the transchoroidal fissure approach for lesions in and around the ambient cistern.OBJECTIVE: Opening the temporal part of the choroidal fissure (CF) makes it possible to expose the crural cistern, the ambient cistern, and the medial temporal lobe. We examined the microsurgical anatomy and the surgical indications for use of the trans-CF approach. methods: The microsurgical anatomy encountered in the trans-CF approach for lesions in and around the ambient cistern was studied in three cadavers. On the basis of these cadaveric studies, the trans-CF approach was used during surgery in three live patients with such lesions. RESULTS: The angiographic "plexal point," which indicates the entrance of the anterior choroidal artery as it enters the temporal horn of the lateral ventricle, was thought to be a key anatomic landmark of the trans-CF approach. A cortical incision for entry into the temporal horn should be made in the inferior temporal gyrus to minimize the potential damage to the optic radiations and to the speech centers. After the CF is opened posteriorly to the plexal point between the tenia fimbria and the choroid plexus, the posterior cerebral artery (PCA) in the ambient cistern can be observed with minimal caudal retraction of the hippocampus. In this study, surgical procedures using the trans-CF approach were successfully performed on patients with high-positioned P2 aneurysms whose PCA ran close to the plexal point or higher, whose medial temporal arteriovenous malformations were fed mainly by the PCA, and whose tentorial hiatus meningiomas protruded into the temporal horn through the CF, with no resulting postoperative visual or memory disturbances. CONCLUSION: The trans-CF approach is especially useful in surgery for lesions in and around the ambient cistern.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
3/20. Bilateral paramedian thalamic infarct in the presence of an unpaired thalamic perforating artery.Bilateral paramedian thalamic infarction is rare. The suggested mechanism is occlusion of a central unpaired thalamic perforating artery--an anatomic variant. In the few existing reports of this condition, the diagnosis was based on computed tomography (CT) or magnetic resonance imaging (MRI) findings alone. Other causes of thalamic lesions were not ruled out, and there was no angiographic demonstration of the presumed variant artery. We present a case of a 48-year-old man with a bilateral thalamic infarction seen on CT and MRI. Initial neurological examination revealed lethargy, severe combined motor and sensory aphasia, and a mild upward gaze limitation. The patient had no focal motor deficits. After 24 hours, the patient was more alert and his speech became more fluent, but Korsakoff-type amnesia with poor attention span became apparent. The patient improved slowly over 6 months of rehabilitation. Bilateral thalamic lesions can be caused by several conditions. Among those are thiamine deficiency, cerebral lupus, toxoplasmosis, cysticercosis, cerebral syphilitic gumma, and even tumors and fungal infections. All these were ruled out in our case. Superselective digital subtraction angiography (DSA) demonstrated a single unpaired thalamic perforator. To our knowledge, this is the first time this anatomical variant has been demonstrated in vivo in association with bilateral thalamic infarction.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
4/20. language localization with activation positron emission tomography scanning.We report the first instance of the use of 3-dimensional magnetic resonance imaging anatomically correlated to positron emission tomography (PET) scanning to identify language areas in a patient with an arteriovenous malformation (AVM) in the posterior speech region. The patient was a 24-year-old right-handed woman with an angiographically proven AVM (3-4 cm) in the left mid-posterior second temporal convolution in whom a left intracarotid injection of sodium Amytal produced significant language disruption. A baseline PET cerebral blood flow study identified the AVM, and an activation PET scan performed during the reading and speaking of simple words showed increased activity in the left parastriate cortex (the second visual area), in the left posterior third frontal convolution (Broca's area), and in the left inferior and midtemporal gyri (Wernicke's area). Increased activity was also noted in the right and left transverse temporal (Heschl's) gyri, in the left precentral gyrus, in the left medial superior frontal gyrus (the supplementary motor area), and in the right cerebellum. We conclude that activation PET scanning is useful in the preoperative assessment of patients who harbor cerebral AVMs in classically described speech regions.- - - - - - - - - - ranking = 2keywords = speech (Clic here for more details about this article) |
5/20. Surgical approach to arteriovenous malformation of the medial temporal lobe--report of three cases.We report three cases of arteriovenous malformation (AVM) of the medial temporal lobe and the surgical approaches used. The AVM was fed by the anterior choroidal artery (AChA) in two cases (Cases 1 and 2) and by the posterior cerebral artery in one (Case 3). The trans-Sylvian approach was first used for cerebrospinal fluid aspiration to retract the brain in all cases, and for confirming the feeding arteries to prevent premature bleeding from the AVM in Cases 1 and 2. In Case 1, a corticotomy was then made in the fusiform gyrus via the subtemporal approach to avoid the development of speech disturbance and visual field defects, while in Cases 2 and 3, a cortical incision was made in the middle temporal gyrus because visual field defects were preoperatively present. Cases 1 and 2 achieved good recoveries, but Case 3 suffered postoperative speech disturbance and died of rebleeding from a recurrent AVM fed by the AChA 22 months after the operation. This AVM was not demonstrated on the postoperative angiograms. We emphasize the usefulness of the combination of trans-Sylvian and subtemporal approaches for this lesion, because the feeding arteries are easily identified and retraction of the temporal lobe is alleviated. A corticotomy in the fusiform gyrus is also recommended to avoid the development of not only visual field defects but also aphasia.- - - - - - - - - - ranking = 2keywords = speech (Clic here for more details about this article) |
6/20. Crossed anomic aphasia: mild naming deficits following right brain damage in a dextral patient.A detailed case study is reported of crossed aphasia (CA) in a dextral patient, bearing upon such controversial issues as intrahemispheric localisation of language function and hemispheric reversal of nonverbal function. DA, a man aged 37, developed a mild naming problem due to right temporal lobe haematoma. Apart from a mild acquired stutter, his continuous speech was fluent and had a normal proportion of open to closed class lexical items. His naming deficit appears to originate in the 'blocking' or 'disconnection' of the phonological lexicon: he could usually give a functional definition of un-named items and retrieve them with the help of a phonemic cue. Lexical retrieval appears his only language deficit, as he had no comprehension or phonological discrimination deficits. DA showed no visuo-spatial or auditory-nonverbal deficits, suggesting the complete reversal of hemispheric specialisation.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
7/20. Cerebellar mutism after posterior fossa surgery.A large midline posterior fossa medulluloblastoma and a cerebellar arteriovenous malformation with associated clot were moved with postoperative mutism. mutism was immediate and resolved into an ataxic dysarthria with residual mild dysarthria at 3 months. The literature is reviewed, and the clinicopathological and neurophysiological data of cerebellar function in speech are discussed. Acute injury to the midportion of the cerebellum with or without dentate nuclear involvement can cause a spectrum of speech disturbances. The more widespread the injury to the midportion of the cerebellum with dentate nuclei involvement the greater the risk of developing postoperative mutism.- - - - - - - - - - ranking = 2keywords = speech (Clic here for more details about this article) |
8/20. Dichotic listening in an aphasic male patient after a subcortical hemorrhage in the left fronto-parietal region.Dichotic listening (DL) performance to consonant-vowel (CV) syllables is reported in an aphasic right-handed male patient. The patient suffered initially from a complete expressive aphasia after an intracerebral hemorrhage caused by the rupture of an arteriovenous malformation (AVM) underlying Broca's area. The patient was tested three times with DL; one week after the hemorrhage, five weeks after, and after at about 6 months. At the first test he could not speak, but understood well. At the second test he uttered one-syllable words, and could answer "yes" and "no" to questions. At the third test he could speak whole sentences, although slow and "stutter-like." Dichotic listening performance showed an almost perfect match with speech recovery. At the first test he showed a left ear advantage which changed to no ear advantage at the second test, and to a right ear advantage at the third test. The overall performance was markedly reduced at the first test, but improved at the following test. It is concluded that dichotic listening may be a valid complement to traditional language assessment procedures after unilateral brain lesions.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
9/20. Neologistic speech automatisms during complex partial seizures.There are no documented cases of seizures causing reiterative neologistic speech automatisms. We report an 18-year-old right-handed woman with stereotypic ictal speech automatisms characterized by phonemic jargon and reiterative neologisms. Video-EEG during the reiterative neologisms demonstrated rhythmic delta activity, which was most prominent in the left posterior temporal region. At surgery, there was an arteriovenous malformation impinging on the left supramarginal gyrus and the posterior portion of the superior temporal gyrus. Though intelligible speech automatisms can result from seizure foci in either hemisphere, neologistic speech automatisms may implicate a focus in the language-dominant hemisphere.- - - - - - - - - - ranking = 8keywords = speech (Clic here for more details about this article) |
10/20. Emotional behavior after a Wada test in a patient with secondary mania.Soon after treatment of a right basotemporal vascular malformation using an embolization procedure, a 25-year-old patient developed an acute episode of mania. Two months later the patient was still manic, and a second embolization was scheduled. Before it was conducted, a Wada test was carried out to determine speech dominance. No changes in manic symptoms were observed after amytal injections into the left middle cerebral, right frontopolar, or right middle cerebral arteries. This finding suggests that secondary mania may not be the result of "release" of the left hemisphere following a right hemisphere lesion but instead may be related to specific disturbances within the right hemisphere.- - - - - - - - - - ranking = 1keywords = speech (Clic here for more details about this article) |
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