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Background: Previous studies to determine memory lateralization with functional MR imaging (fMRI) have used encoding or recall tasks. The convergence between the results of both tasks, however, is unknown., Objective: The objective of this study was to investigate hemispheric asymmetries of temporal lobe activity (parahippocampus and fusiform gyri) in patients with temporal lesions by using both kinds of fMRI tasks., Methods: By using blood oxygenation level-dependent fMRI, hemispheric asymmetries of 25 consecutive patients admitted for presurgical evaluation of memory and 12 healthy control participants were studied. Activation was induced by using the picture-encoding task (processing of complex scenes) and the hometown-walking task (requiring mental navigation through one's hometown by using landmarks given by participants themselves)., Results: Results in the control group showed that both tasks activated the parahippocampus similarly. The picture-encoding task, however, yielded greater posterior activations in the parahippocampus than did the hometown-walking task. As observed in other studies, more than half the patients showed contralesional representation of memory in each task. It is important to note that estimated memory lateralization from each task was different in 30% of patients, and several cases showed clear discrepancies between both tasks., Conclusion: Although previous studies showed that both tasks were useful for evaluating memory lateralization, the present study suggested that the administration of both tasks is necessary for presurgical evaluation of memory lateralization in patients with lesions in the temporal lobe. Therefore, both encoding and recall processes should at least be considered in the evaluation of memory.

The aim of this paper is to review the specific problems of the microsurgical management of the acoustic neuromas not suitable for radiosurgical treatment , that is measuring more than 8 cc in volume or 2.5 cm in maximum diameter in the cerebelopontine angle. A total of 18 lesions have been included with a mean volume of 27.4 cc, representing a lesion measuring 3.8 cm in its three main diameters. The mean follow-up has been 48.7 months. There has been no mortality. All lesions were completely excised without recurrences. The anatomic conservation of the facial nerve was achieved in the 66.7% of the cases but the functional recovery (House-Brackmann grades I-II) was reached only in the 27.8%, without any grade I case. As permanent deficit all patients had postoperative cophosis, two had trigeminal hyposthesia with corneal anesthesia and one had a cerebellar deficit. The main conclussion is that the microsurgical radical resection of large acoustic neuromas not suitable for radiosurgical treatment is followed by a high postoperative morbidity mainly related with the facial nerve lesion. Therefore, it seems rationale to design specific strategies directed to reduce and alleviate these permanent deficits.

The assessment of memory functions related to medial temporal lobe has become one of the most important issues on current neuropsychology. On this communication, we review the results which our research group has achieved using two functional magnetic resonance Image procedures to assess memory function: Hometown walking task and an encoding/retrieval task using complex images. Nine patients with tumoural temporal lesions performed the hometown walking task. The results of these patients showed either a bilateral or contralesional representation of memory function. These results confirm those obtained by Jokeit, Okujava y Woermann (2001), and they seem to prove that this protocol is useful to determine the preservation of memory function in the non damaged hemisphere. On the other hand, the images encoding/retrieval task has been run by two groups of four patients diagnosed as Alzheimer disease and mild cognitive impairment, and another group of five patients who participated as a control group. According to our hypothesis, the results have shown a lower activation at the left parahippocampal gyrus in mild cognitive impairment and Alzheimer disease patients than controls, just as a lower bilateral activation in the same structure for the Alzheimer group than the control group. As a whole, our results show how important may become functional magnetic resonance image for neuropsychological assessment of memory, and as a diagnostic tool for CNS diseases.

Aims: This paper reviews and describes cases involving useful protocols for pre-surgical evaluation in functional magnetic resonance imaging (fMRI) of the motor, mnemonic and linguistic functions., Development: The application of fMRI in pre-surgical evaluation allows us to pinpoint the anatomical location of a function in relation to the lesion. This technique therefore appears as an alternative to the classical intraoperative tests, which are more aggressive and costly. The paper describes aspects and considerations of fMRI with regard to the methodology and procedure employed in its application, as well as the control of contaminating variables that can affect results. The language protocols are described in terms of lateralisation and localisation, and are divided into expressive and receptive language protocols, together with linguistic protocols for overall stimulation that allow the localisation of both expressive and receptive areas. Concerning the motor protocols, we describe the procedures for patients with and without difficulties in their movement. Lastly, we review and describe the memory protocols that give rise to bilateral stimulation in the mesial temporal areas, which allows both lateralisation and localisation of the hippocampal and parahippocampal areas that are functionally significant for the patients' memory. Each of the protocols is illustrated with cases carried out by our work team., Conclusions: The development of new protocols for pre-surgical evaluation must be guided by greater delimitation and consistency in functional stimulation, as well as analysis of the behaviour displayed.

A patient with association of Klippel-Feil syndrome and posterior fossa dermoid cyst is presented. The patient, a 36-year-old man, presented with an acute obstructive hydrocephalus due to the cyst and exhibited the typical triad of the Klippel-Feil abnormality with short neck, low hairline implantation and limited neck motion along with a complex cervical vertebrae fusion. The anatomical and clinical features as well as the pathophysiology of this rare association are discussed after a review of the literature.

The personal experience in the treatment of the spinal and paraspinal thoracic pathology using the paraspinal retropleural approach is presented. A total of 18 patients with neoplastic, traumatic and discal lesions were operated on. Improvement of neurological disturbances and pain was noted in all patients. The surgical technique for spinal cord and root decompression and also for anterior and/or posterior stabilization of the spine is described. The paraspinal retropleural approach is compared with the anterior transthoracic approach. The advantages of the paraspinal retropleural approach are: low rate of complications; allows a very wide decompression of the neurological elements as well as an anterior and/or posterior stabilization of the spine by a single approach; and it can be easily tailored for each lesion. These advantages are enhanced in the management of lesions located in the upper thoracic or thoracocervical levels.

Objective: To compare clinical and radiologically three methods of cervical arthrodesis after anterolateral one-level discectomy for non-traumatic disk disease., Materials and Methods: Three groups of patients were studied retrospectively. In group 1 (20 patients) a tricortical autologous iliac crest bone interbody graft was used. In group 2 (10 patients) the bone graft was associated to an anterior cervical plate (Stryker). In group 3 (10 patients) a cage-plate filled with iliac crest trabecular bone was implanted (plate-cage GD). Clinical and radiological parameters were recorded preoperatively and 6-9 months postoperatively., Results: There was a significant clinical improvement in all three groups, with similar complications and hospitalization time. There were not hard-ware failures. There was a significant increase in the disc height in group 3 when compared with group 1 and a significant correction of the preoperative kyphosis in group 3 in relation to both group 1 and 2: There was a significant increase in postoperative radiological stability rate and also in the operative time in groups 2 and 3 when compared with group 1., Conclusions: Cervical arthrodesis after discectomy is an useful method for treatment of cervicobrachialgia. Arthrodesis with internal fixation achieves best clinical and radiological results and it has some other advantages in relation to bone graft artrhodesis. GD cage-plate minimizes the surgical and clinical problems associated with use of bone graft and cervical plate and reaches the best radiological performances.