A review of the clinical significance of lumbar puncture in the diagnostic approach of Aneurysmal Subarachnoid Hemorrhage (SAH): A case report of CT-Negative and Lumbar Puncture–Positive SAH

@#Headaches are a common presentation in the emergency department (ED). Even though not all are potentially serious, some such as subarachnoid hemorrhage (SAH) can be more dangerous than others. SAH is a medical emergency with an almost 50% mortality rate. It is crucial not to miss the diagnosis of SAH, as a missed or delayed diagnosis can be severely detrimental. It classically presents as thunderclap headache, a severe, sudden-onset headache. There are various approaches in diagnosing or excluding SAH, which is classically done by performing a computed tomography (CT) scan followed by a lumbar puncture (LP). But with the improved sensitivity of more modern diagnostic tools, more physicians are in support of changing this classical teaching. The aim of this case report is to review the advantages and disadvantages of LP in diagnosing SAH, along with other diagnostic tools commonly used.

The Brain-MR Studies in the Brain Death Patient: Report of 3 Cases: The Utility of the Anesthetic Mapleson Circuit-F System

Brain-MR studies are sensitive to intracranial ischemia and vascular flow. However, brain MR study for brain death is clinically limited because keeping the ventilation is difficult during study. In our hospital, three 'brain death patients' brain-MR studies were performed under the anesthetic Mapleson's circuit-F system. Three patients' clinical states were not changed after the studies. We confirmed that brain herniation, absent intracranial flow void, no intracranial contrast enhancement, poor gray/white matter differentiation, and prominent nasal enhancement findings. The value of brain-MR study for brain death may be possible.

Evaluation of the Somatotopic Organization of Corticospinal Tracts in the Internal Capsule and Cerebral Peduncle: Results of Diffusion-Tensor MR Tractography

OBJECTIVE: We have used diffusion tensor tractography (DTT) for the evaluation of the somatotopic organization of corticospinal tracts (CSTs) in the posterior limb of the internal capsule (PLIC) and cerebral peduncle (CP). MATERIALS AND METHODS: We imaged the brains of nine healthy right-handed subjects. We used a spin-echo echo-planar imaging (EPI) sequence with 12 diffusion-sensitized directions. DTT was calculated with an angular threshold of 35 degrees and a fractional anistropy (FA) threshold of 0.25. We determined the location of the CSTs by using two regions of interest (ROI) at expected areas of the pons and expected areas of the lateral half of the PLIC, in the left hemisphere of the brain. Fiber tracts crossing these two ROIs and the precentral gyrus (PCG) were defined as CSTs. Four new ROIs were then defined for the PCG, from the medial to lateral direction, as ROI 1 (medial) to ROI 4 (lateral). Finally, we defined each fiber tract of the CSTs between the pons and each ROI in the PCG by using two ROIs methods. RESULTS: In all subjects, the CSTs were organized along the long axis of the PLIC, and the hand fibers were located anterior to the foot fibers. The CSTs showed transverse orientation in the CP, and the hand fibers were located usually medial to the foot fibers. CONCLUSION: Corticospinal tracts are organized along the long axis of the PLIC and the horizontal direction of the CP.

MR Imaging of a Cerebello-Pontine Angle Epidermoid Cyst with a Malignant Transformation: Case Report

The malignant transformation of an epidermoid cyst can be discovered at the same time as a pre-existing epidermoid cyst, or during a follow-up examination after an incomplete excision. We describe a rare case of malignant transformation of a cerebello-pontine angle epidermoid cyst which extended into the middle cerebellar peduncle.

Antenatal Diagnosis of Iniencephaly: Sonographic and MR Correlation: A Case Report

Iniencephaly is an uncommon and fatal neural tube defect involving the occiput and inion, this occurs together with rachischisis of the cervical and thoracic spine, and retroflexion of the head. We report the ultrasound (US) and magnetic resonance (MR) imaging findings of a case of iniencephaly with clubfeet and arthrogryposis. The diagnosis of iniencephaly is easy to make on ultrasound due to the typical star-gazing fetus. However, the details of the fetal brain and spinal cord may not be adequately delineated on US. We found MR imaging to be superior for depicting central nervous system abnormalities. MR imaging has evolved as an imaging modality and it is complementary to fetal US, yet US remains the screening modality of choice.

Diffusion-Weighted Imaging with Sensitivity Encoding (SENSE) for Detecting Cranial Bone Marrow Metastases: Comparison with T1-Weighted Images

OBJECTIVE: This study was designed to determine whether diffusion-weighted imaging (DWI) with sensitivity encoding (SENSE) could detect bone marrow involvement in patients with cranial bone marrow (CBM) metastases. DWI results obtained were compared with T1-weighted imaging (T1WI) findings. MATERIALS AND METHODS: DWI with sensitivity encoding (SENSE; b value = 1,000) was performed consecutively in 13 patients with CBM metastases diagnosed pathologically and radiologically. CBM lesions were dichotomized according to the involved site, i.e., skull base or calvarium. Two radiologists qualitatively evaluated the relative conspicuousness of CBM lesions and image qualities in B0 and in isotropic DWI and in T1WI. According to region of interest analysis of normal and pathologic marrow for these three sequences, absolute signal difference percentages (SD%) were calculated to quantitatively analyze lesion contrast. RESULTS: All 20 lesions in 13 patients with CBM metastases revealed abnormal DWI signals in areas corresponding to T1WI abnormalities. Both skull base and calvarial lesions provided better lesion conspicuousness than T1WI and B0 images. Although the image quality of DWI was less satisfactory than that of T1WI, relatively good image qualities were obtained. Quantitatively, B0 images (SD%, 82.1+/-7.9%) showed better lesion contrast than isotropic DWI (SD%, 71.4+/-13.7%) and T1WI (SD%, 65.7+/-9.3%) images. CONCLUSION: For scan times of less than 30 seconds, DWI with SENSE was able to detect bone marrow involvement, and was superior to T1WI in terms of lesion conspicuity. DWI with SENSE may be helpful for the detection of cranial bone/bone marrow metastases when used in conjunction with conventional MR sequences.

The Significance of Vascular MR Contrast Enhancement in Carotid Stenosis

PURPOSE: To determine the significance of vascular MR contrast enhancement in carotid stenosis. MATERIALS AND METHODS: Forty patients that had angiographically proved carotid stenosis were selected for the study. A blind interpretation of vascular enhancement on an enhanced T1 weighted image, the lesion pattern on a DWI (diffusion weighted image), a perfusion defect on a MR perfusion image, the degree of stenosis, and collateral flow on cerebral DSA (digital subtraction angiography) was made by two observers, retrospectively. DWI lesion patterns were classified as having no high signal intensity, small PAI (perforating artery infarcts), large PAI, pial infarcts, territorial infarcts, and border zone infarcts. We evaluated the statistical correlation between vascular enhancement and the degree of stenosis, collateral flow, the DWI lesion pattern and the presence of a perfusion defect, respectively. RESULTS: The degree of carotid stenosis and the frequency of vascular enhancement correlated statistically (p=0.000). The presence of retrograde collateral flow on cerebral DSA and the border zone infarcts pattern on DWI were related with the occurrence of vascular enhancement (p=0.002, p=0.004). In 23 patients that underwent a MR perfusion study, the presence of a perfusion defect was also related to the occurrence of vascular enhancement (p=0.002). CONCLUSION: Vascular MR contrast enhancement may indicate a cerebral hypoperfusion in carotid stenosis.

Usefulness of Post-enhanced Delayed FLAIR Imaging for Making the Diagnosis of Leptomeningitis

PURPOSE: To evaluate the usefulness of post-enhanced delayed FLAIR (fluid-attenuated inversion-recovery) images in the diagnosis of leptomeningitis. MATERIALS AND METHODS: We obtained the pre- and post-enhanced FLAIR images of 7 rabbits every hour after infusing triple doses of contrast, and we measured the signal intensities of the CSF (cerebrospinal fluid) and the brain parenchyma. Five leptomeningitis patients and 5 volunteers were enrolled to obtain the pre-enhanced FLAIR images, the early post-enhanced FLAIR images and the delayed post-enhanced FLAIR images, with using a standard dose of contrast, and to measure the signal intensities of the CSF and brain parenchyma. The statistical significances were determined by a mixed procedure and the Wilcoxon rank-sum test (p<0.05). RESULTS: In the rabbits, the signal intensities of the CSF began to increase after an hour of contrast infusion, but those of the parenchyma did not increase. The time of maximum CSF enhancement was 2 hours after contrast infusion (p<0.001; standard estimate=750.43) and we obtained the post-enhanced delayed FLAIR images for clinical studies according to this result. The signal intensities of the CSF in the subarachnoid space were higher in the patient group compared with those of the normal control group on both the early post-enhanced FLAIR images and the delayed post-enhanced FLAIR images (p=0.0096) (p=0.0391). In the patient group, changes of signal intensities of the CSF in the subarachnoid space were more conspicuous on the delayed post-enhanced FLAIR images than on the early post-enhanced FLAIR images (p=0.0042). However, those of the parenchyma were not different in either group. CONCLUSION: The post-enhanced delayed FLAIR images obtained at 2 hours after contrast infusion are more useful for making the the diagnosis of leptomeningitis than are the post-enhanced early FLAIR images.

MR findings in Acute Disseminated Encephalomyelitis in Children

PURPOSE: We reviewed the distribution of lesion and the characteristics of the MR findings of acute disseminated encephalomyelitis (ADEM) in children. We evaluated the differences in the imaging findings and the clinical outcomes between the patients with deep gray matter involvement and the patients without deep gray matter involvement. MATERIALS AND METHODS: We retrospectively reviewed the 62 MR examinations of 21 patients who were discharged with the clinical diagnosis of ADEM. The patients were aged from 13 months to 12 years old (mean age: 4.5 years). Follow-up MR examinations were done one to 5 times (mean: 3 times) for 2 weeks to 4 years (mean: 3 months) after the initial examination. We compared the signal intensity on T2WI, the enhancement and residue on the MR images and the clinical outcomes between the patients with deep gray matter involvement and the patients without deep gray matter involvement. RESULTS: A total of 21 patients had white matter abnormalities on their initial MR. Fifteen patients (71%) had foci of increased signal intensity on T2WI in the deep gray matter: thalamus (n=15), globus pallidus (n=14) and putamen (n=10). On the follow-up images, all patients showed decreased signal intensity and enhancement of their lesion. We could not find the significant differences in signal intensity, enhancement and residue on the MRIs and also the clinical outcomes between the patients with deep gray matter involvement and the patients without deep gray matter involvement (<.05). CONCLUSION: There were no significant differences in the characteristics of the imaging and the clinical outcomes between the ADEM patients with deep gray matter involvement and those ADEM patients without deep gray matter involvement.

PROPELLER (periodically rotated overlapping parallel lines with enhanced reconstruction) and EPI Diffusion-weighted MR Imaging at 3.0T: Pontine Magnetic Susceptibility Artifacts Depend on Pneumatization of the Sphenoid Sinus

PURPOSE: In the case of well pneumatized sphenoid sinus, magnetic susceptibility artifact can be visualized at the brainstem and especially at the pons on echo-planar imaging (EPI) diffusion-weighted imaging. Fast spin-echo periodically rotated overlapping parallel lines with enhanced reconstruction (PROPELLER) is a novel imaging method that can reduce these artifacts. In 3.0T MR, we first evaluate the degree of the relationship of pneumatization of the sphenoid sinus with the occurrence of magnetic susceptibility artifacts (MSA) on the echo planar imaging (EPI) diffusion-weighted imaging (DWI), and we evaluated using PROPELLER-DWI for cancellation of MSAs of the pons in the patients who had MSAs on the EPI-DWI. MATERIALS AND METHODS: Sixty subjects (mean age: 58 years old and there were 30 men) who were classified according to the two types of sphenoid sinus underwent EPI-DWI. The two types of sphenoid sinus were classified by the degree of pneumatization on the sagittal T2-weighted image. The type-1 sphenoid sinus was 0% to less than 50% aeration of the bony sellar floor, and type-2 was 50% or more aeration of the boney sellar floor. Each of 10 subjects (n=20/60, mean age: 53) of the two types had PROPELLER and EPI-DWI performed simultaneously. We first evaluated the absence or presence of MSAs at the pons in the two types, and we compared EPI and PROPELLER-DWI in the subjects who underwent the two MR sequences simultaneously. We used 3.0T MR (Signa VHi, GE, MW, U.S.A.) with a standard head coil. All the MR images were interpreted by one neuroradiologiest. RESULTS: For the type-1, two (6.7%) cases had MSAs and 28 (93.7%) cases did not have MSAs on the EPI-DWI. For the type-2, twenty-seven (90%) cases had MSAs and 3 (10%) cases did not have MSAs on the EPI-DWI. The degree of pneumatization of the sphenoid sinus was related with the occurrence of MSAs of the pons, according to the chi-square test (p=0.000). All twenty cases who had PROPELLER-DWI performed had no MASs at the pons regardless of the type of sphenoid sinus. But all ten cases of type-2 produced MASs on the EPI-DWIs CONCLUSION: For EPI-DWI, a well aerated sphenoid sinus can induce MASs at the pons, and we should recognize this phenomenon to differentiate it from true infarcted lesion. PROPELLER DWI can be an optional tool to use for canceling this artifact.

CT and MR Imaging Findings of Subdural Dermoid Cyst Extending into the Right Foramen Ovale: A Case Report

Intracranial dermoid cyst is a rare congenital benign disease, representing less than 0.5% of primary brain tumors. Nevertheless, if ruptured spontaneously or during surgery, it has a poor prognosis due to chemical meningitis. Therefore, it is essential to perform accurate diagnosis and proper treatment. We report an intracranial subdural dermoid cyst that may be misdiagnosed as extracranial or epidural lesion because of extension into the right foramen ovale, and describe the CT and MR imaging findings.

Histogram Analysis of Noise Performance on Fractional Anisotropy Brain MR Image with Different Diffusion Gradient Numbers

PURPOSE: We wished to analyze, qualitatively and quantitatively, the noise performance of fractional anisotropy brain images along with the different diffusion gradient numbers by using the histogram method. MATERIALS AND METHODS: Diffusion tensor images were acquired using a 3.0 T MR scanner from ten normal volunteers who had no neurological symptoms. The single-shot spin-echo EPI with a Stejskal-Tanner type diffusion gradient scheme was employed for the diffusion tensor measurement. With a b-valuee of 1000 s/mm2, the diffusion tensor images were obtained for 6, 11, 23, 35 and 47 diffusion gradient directions. FA images were generated for each DTI scheme. The histograms were then obtained at selected ROIs for the anatomical structures on the FA image. At the same ROI location, the mean FA value and the standard deviation of the mean FA value were calculated. RESULTS: The quality of the FA image was improved as the number of diffusion gradient directions increased by showing better contrast between the WM and GM. The histogram showed that the variance of FA values was reduced as the number of diffusion gradient directions increased. This histogram analysis was in good agreement with the result obtained using quantitative analysis. CONCLUSION: The image quality of the FA map was significantly improved as the number of diffusion gradient directions increased. The histogram analysis well demonstrated that the improvement in the FA images resulted from the reduction in the variance of the FA values included in the ROI.

Brain Diffusion Tensor MR Imaging

The development of MR imaging techniques during the past decade has enabled researchers to use MR imaging as a noninvasive tool for evaluating structural and physiologic states in biologic tissues by measuring the diffusion process of water molecules. More recently, diffusion tensor MR imaging (DTI) technique based on the dependency of molecular diffusion on the orientation of white matter fiber tracts has been used to analyze the trajectory, shape, fiber structure, location, topology and connectivity of neuronal fiber pathways in living humans. Numerous efforts have been made by MR physicists, brain scientists, and medical doctors to advance MR techniques and computer-based algorithms which result in more accurate quantification of diffusion tensor and the generation of white matter fiber tract maps and to determine the pathophysiology of brain disease by DTI and useful clinical applications of DTI. In this article, we describe the tensor theory used to characterize molecular diffusion in white matter and a process of measuring tensor elements using diffusion-sensitive MR images to fiber mapping. We then provide review of current literature and some clinical examples that have been published and are on-going.

Imaging of the Ischemic Penumbra in Acute Stroke

One of the main reasons for the soaring interest in acute ischemic stroke among radiologists is the advent of new magnetic resonance techniques such as diffusion-weighted imaging. This new modality has prompted us to seek a better understanding of the pathophysiologic mechanisms of cerebral ischemia/infarction. The ischemic penumbra is an important concept and tissue region because this is the target of various recanalization treatments during the acute phase of stroke. In this context, it is high time for a thorough review of the concept, especially from the imaging point of view.

Assessment of Tissue Viability Using Diffusion- and Perfusion-Weighted MRI in Hyperacute Stroke

OBJECTIVE: The aim of this study was to investigate the relationship between the diffusion and perfusion parameters in hyperacute infarction, and we wanted to determine the viability threshold for the ischemic penumbra using diffusion- and perfusion-weighted imaging (DWI and PWI, respectively). MATERIALS AND METHODS: Both DWI and PWI were performed within six hours from the onset of symptoms for 12 patients who had suffered from acute stroke. Three regions of interest (ROIs) were identified: ROI 1 was the initial lesion on DWI; ROI 2 was the DWI/PWI mismatch area (the penumbra) that progressed onward to the infarct; and ROI 3 was the mismatch area that recovered to normal on the follow-up scans. The ratios of apparent diffusion coefficient (ADC), the relative cerebral blood volume (rCBV), and the time to peak (TTP) were calculated as the lesions' ROIs divided by the contralateral mirror ROIs, and these values were then correlated with each other. The viability threshold was determined by using the receiver operating characteristic (ROC) curves. RESULTS: For all three ROIs, the ADC ratios had significant linear correlation with the TTP ratios (p < 0.001), but not with the rCBV ratios (p = 0.280). There was no significant difference for the ADC and rCBV ratios within the ROIs. The mean TTP ratio/TTP delay between the penumbras' two ROIs showed a significant statistical difference (p < 0.001). The cutoff value between ROI 2 and ROI 3, as the viability threshold, was a TTP ratio of 1.29 (with a sensitivity and specificity of 86% and 73%, respectively) and a TTP delay of 7.8 sec (with a sensitivity and specificity of 84% and 72%, respectively). CONCLUSION: Determining the viability thresholds for the TTP ratio/delay on the PWI may be helpful for selecting those patients who would benefit from the various therapeutic interventions that can be used during the acute phase of ischemic stroke.

The Usefulness of 3T-TOF MR angiography in Patients with Cerebral Infarction

PURPOSE: This study was designed to evaluate the usefulness of 3T-TOF MR angiography (3T-TOF MRA) compared with transcranial Doppler sonography (TCD) and conventional angiography (CA) in patients with suspected cerebral infarction. MATERIALS AND METHODS: Fifty four patients with clinical symptoms of cerebral infarction were involved in this study, and had undergone 3T-TOF MRA and TCD, with CA in 11 patients. On the basis of divisions of the carotid artery, four groups were designated: group I, both vertebral arteries and basilar artery; group II, segment between 2 cm below bifurcation of common carotid artery and genu portion of internal carotid artery; group III, segment between petrous portion of internal carotid artery and bifurcation of anterior and middle cerebral artery; group IV, from bifurcation of anterior and middle cerebral artery to thier distal branches. Two radiologists retrospectively reviewed the vascular imaging and stenosis in 3T-TOF MRA, TCD, and CA. RESULTS: A total of 432 arteries, 108 in each group, were available. The assessment of vascular imaging quality in 3T-TOF MRA is scored 2.98, 2.96, 2.91, 2.88 in 4 groups, respectively. Agreement among 3TTOF MR angiography, TCD, and CA was high. CONCLUSION: 3T-TOF MR angiography may be useful method for the assessment of stenotic lesions of cranial vasculature in patients with cerebral infarction.

Postcontrast T1-weighted Brain Magnetic Resonance Imaging in Pediatric Patients: Comparison Between Postcontrast Fat-suppression Imaging and Conventional T1-weighted or Magnetization Transfer Imaging

PURPOSE: We wished to assess the merits and weaknesses of postcontrast fat-suppression (FS) brain MR imaging in children for the evaluation of various enhancing lesions as compared with postcontrast conventional T1-weighted or magnetization transfer (MT) imaging. MATERIALS AND METHODS: We reviewed the records of those patients with enhancing lesions on brain MR imaging who had undergone both FS imaging and one of the conventional T1-weighted or MT imaging as a postcontrast T1-weighted brain MR imaging. Thirty-one patients (21 male, 10 female; mean age, 8.7 years) with 38 enhancing lesions (18 intra-axial, 16 extra-axial and 4 orbital locations) were included in this study. There were 27 pairs of FS and conventional imagings, and 13 pairs of FS and MT imagings available for evaluation. Two radiologists visually assessed by consensus the lesions' conspicuity, and they also looked for the presence of flow or susceptibility artifacts in a total of 40 pairs of MR imagings. For 19 measurable lesions (14 pairs of FS and conventional T1-weighted imagings, 5 pairs of FS and MT imagings), the contrast ratios between the lesion and the normal brain ([SIlesion-SIwater]/[SInormal brain-SIwater]) were calculated and compared. RESULTS: Compared with conventional imaging, the lesion conspicuity on FS imaging was better in 10 cases (7 extra-axial lesions, 2 orbital lesions and 1 fat-containing intra-axial lesion), equal in 16 cases, and worse in one case. Compared with MT imaging, the lesion conspicuity on FS imaging was better in 3 cases (2 extra-axial lesions and 1 intra-axial lesion), equal in 8 cases, and worse in 2 cases. Image quality of FS imaging was compromised by flow or susceptibility artifacts for 7 patients. The contrast ratios for FS imaging were not significantly different from those for conventional imaging (2.2+/-0.7 vs. 2.2+/-0.6, respectively, p=0.914) and they were significantly lower than those for MT imaging (2.4+/-0.8 vs. 4.5+/-1.5, respectively, p=0.018). CONCLUSION:Postcontrast FS brain MR imaging appears to be better than the conventional T1-weighted imaging and comparable to MT imaging for the visual assessment of enhancing lesions. Especially, the FS imaging has the merit to delineate orbital and extra-axial enhancing lesions or fat-containing lesions, whereas it is disadvantageous when flow or susceptibility artifacts occur.

Measuring of the Cerebellar Volume of Normal Koreans in Their 20s and 40s Using Magnetic Resonance Imaging

PURPOSE: This study purposed to measure the standard volume of the cerebellum of normal Koreans who were in their 20s and 40s, and we also wished to find out the difference in the volume of the cerebellum according to gender and age. MATERIALS AND METHODS: This study collected MR brain images from 118 people in their 20s (males: 58, females: 60) and 100 people in their 40s (males: 41, females: 59), for a total of 218 people. For each of sagittal, coronal and axial sections, the cerebellar part of the images was segmented using automatic and manual methods, and the volume was then measured. In order to observe differences according to gender and age and also to observe the interactive effect between gender and age, a two-way ANOVA test was performed using gender (2 levels) and age (2 levels) as independent variables. RESULTS:The average volume of the cerebellum of Koreans in their 20s was 133.74 (cm3) and that of Koreans in their 40s was 121.83 (cm3). The average volume of the cerebellum of male Koreans in their 20s and 40s was 134.55 (cm3) and that of female Koreans was 123.06 (cm3). The volume of the cerebellum was significantly larger in Koreans in their 20s than those volumes of the cerebellum of Koreans in their 40s, and the cerebellum volumes in male Koreans were larger than those of the Korean females. Moreover, the reduction of the volume of the cerebellum with age was significantly larger in male Koreans than in the Korean females. CONCLUSION: According to the results of measuring the volume of the cerebellum for normal Koreans in their 20s and 40s, the volume was significantly different according to gender and age, and the reduction of the volume of the cerebellum with age was significantly larger in men than in women.

Middle Cranial Fossa Epidermoid Cyst: A Case Report of Unusual CT and MR Findings

Intracranial epidermoid cysts usually show homogeneous hypodensity on CT scans, hypointensity on T1-weighted MR images and hyperintensity on T2-weighted MR images. Most of them arise in the cerebellopontine angle and parasellar areas. We report a case of middle cranial fossa epidermoid tumor with unusual image findings. The entire tumor mass showed inhomogeneous low density, without any enhancing solid portion on the CT scans. The lateral portion of the tumor showed homogeneous T1 low signal intensity and T2 high signal intensity. The medial portion of the tumor showed heterogeneous T1 and T2 intermediate to high signal intensity. On the gadolinium enhanced MR images, enhancement of the thickened dura was observed behind the tumor. Surgery and pathologic examination revealed the presence of an extradural epidermoid cyst.

Somatotopic Mapping of the Supplementary Motor Area

PURPOSE: The purpose of this study was to assess supplementary motor area (SMA) activation during motor, sensory, word generation, listening comprehension, and working memory tasks using functional magnetic resonance imaging (fMRI). MATERIALS AND METHODS: Sixteen healthy right-handed subjects (9M, 7F) were imaged on a Siemens 1.5T scanner. Whole brain functional maps were acquired using BOLD EPI sequences in the axial plane. Each paradigm consisted of five epochs of activation vs. the control condition. The activation tasks consisted of left finger complex movement, hot sensory stimulation of the left hand, word generation, listening comprehension, and working memory. The reference function was a boxcar waveform. Activation maps were thresholded at an uncorrected p=0.0001. The thresholded activation maps were placed into MNI space and the anatomic localization of activation within the SMA was compared across tasks. RESULTS: SMA activation was observed in 16 volunteers for the motor task, 11 for the sensory task, 15 for the word generation task, 5 for the listening comprehension task, and 15 for the working memory task. The rostral aspects of the SMA showed activity during the word generation and working memory tasks, and the caudal aspects of the SMA showed activity during the motor and sensory tasks. Right (contralateral) SMA activation was observed during the motor and sensory tasks, and left SMA activation during the word generation and memory tasks. CONCLUSION: Our results suggest that SMA is involved in a variety of functional tasks including motor, sensory, word generation, and working memory. The results obtained also support the notion that functionally specific subregions exist within the region classically defined as the SMA.