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T Sugahara

Publications and source records attributed to T Sugahara.

At least 73 records · Page 4Linked to original sources
PubMed1999

Contrast enhancement of intracranial lesions: conventional T1-weighted spin-echo versus fast spin-echo MR imaging techniques.

BACKGROUND AND PURPOSE: The T1-weighted fast spin-echo (T1-FSE) MR imaging sequence is not used routinely, since the speed advantage is not as dramatic as it is in T2-weighted imaging. We evaluated the T1-FSE sequence to determine whether this technique can replace the conventional T1-weighted spin-echo (T1-SE) sequence for routine contrast-enhanced imaging. METHODS: Sixty-nine patients with intracranial enhancing lesions underwent both T1-SE and T1-FSE sequences in a random order after administration of contrast agent. Acquisition time was 55 seconds for the T1-FSE sequence and 2 minutes 38 seconds for the SE sequence. The conspicuity of enhancing lesions, peritumoral edema, and gray-to-white matter contrast as well as motion and flow artifacts were analyzed. Signal-to-noise ratios of enhancing lesions, gray matter, and white matter as well as contrast-to-noise ratios (CNRs) of enhancing lesions, with gray matter with white matter as the standard, were calculated. RESULTS: The conspicuity of enhancing lesions was better on T1-FSE sequences than on T1-SE sequences, although the difference in the CNRs of enhancing lesions did not reach significance. Images obtained with the T1-FSE sequence showed less flow and motion artifacts than did those obtained with the T1-SE sequence. The conspicuity of peritumoral edema and gray-to-white matter contrast was lower on the T1-FSE images than on the T1-SE images. CONCLUSION: The T1-FSE sequence reduces imaging time and has the potential to replace the conventional T1-SE sequence for the evaluation of enhancing lesions in the brain when time is a consideration.

Adolescent↗
PubMed1998

Lethality of high linear energy transfer cosmic radiation to Escherichia coli DNA repair-deficient mutants during the 'SL-J/FMPT' space experiment.

We investigated the lethal and mutagenic effects of high linear energy transfer cosmic radiation on 11 strains of Escherichia coli, including DNA repair-deficient mutants, using the Radiation Monitoring Container and Dosimeter in the space shuttle 'Endeavour' as part of the 'SL-J/FMPT' space experiment, the 'Fuwatto '92' project. After the return to earth of the shuttle, we evaluated survival and mutations of samples in space and matched controls. The surviving fractions were determined by means of colony count on broth agar plates, and the mutation frequencies were estimated by appearance of arg' revertants on minimal agar plates. The average of the total equivalent dose rate during this space flight was 0.202 mSv/day as measured by the plastic radiation detectors and the thermoluminescent dosimeters in the Radiation Monitoring Container and Dosimeter. The combined action of DNA polymerase and 3'-->5' exonuclease activities was found to make the greatest contribution to the repair of cosmic radiation-induced DNA damage, 5'-->3' exonuclease and recombination repair enzyme activities made a moderate contribution, whereas UV endonuclease activity was not involved in this DNA repair process.

Colony Count, Microbial↗
PubMed1998

A novel function of enolase from rabbit muscle; an immunoglobulin production stimulating factor.

Rabbit muscle enolase stimulates immunoglobulin production by a human hybridoma line, HB4C5 cells under serum-free condition. IgM productivity of HB4C5 cells was enhanced more than 20-fold by this enzyme at 220 micro/ml. Human peripheral blood lymphocytes were also facilitated their IgM and IgG productivity in the serum-free medium. However, baker's yeast enolase was ineffective to accelerate immunoglobulin production by HB4C5 cells, in spite of the same specific enzymatic activity as rabbit muscle enolase. There were differences in sensitivities against heat treatment and trypsin digestion between IPSF and enzymatic activities of enolase. These results imply that the immunoglobulin production stimulating effect of rabbit muscle enolase is irrelevant to its enzymatic function and reaction products. This fact also means that this enzyme has another function other than enzymatic one in glycolysis. Rabbit muscle enolase enhanced IgM production of transcription-suppressed HB4C5 cells treated with actinomycin D. Cycloheximide treatment of HB4C5 cells was useless to inhibit the expression of immunoglobulin production stimulating activity. However, inhibition of post-transcriptional process by monensin invalidated the activity of enolase. These findings suggest that enolase from rabbit muscle accelerates the steps between translation and post-translational processes to enhance immunoglobulin productivity. In addition, laser confocal microscopic analysis revealed that enolase from rabbit muscle was subsequently incorporated by HB4C5 cells.

Animals↗
PubMed1998

Virtual MRI endoscopy of the intracranial cerebrospinal fluid spaces.

We used constructive interference in steady state (CISS) 3D Fourier transform (3DFT) MRI data sets to obtain three-dimensional (3D) virtual MRI endoscopic views of the intracranial cerebrospinal fluid (CSF) spaces, processing them with a commercially available perspective endoscopic algorithm. We investigated the potential of the intracranial virtual MRI endoscopy applied to visualisation of the pathology in 13 patients with surgically confirmed trigeminal neuralgia (3), hemifacial spasm (3), acoustic neuroma (3), suprasellar germinoma (1), Langerhans cell histiocytosis (1), lateral ventricle nodules (1) and pituitary dwarfism (1). All images were acquired using a 1.5-T imager employing a circular polarised head coil. The CISS-3DFT data sets were transferred to a workstation for processing with the perspective endoscopic algorithm. Postprocessing for virtual MRI endoscopy was possible for all data sets. The lesions in 12 patients, and their complex anatomical relationships with the surrounding structures, were well seen on the 3D images. A small acoustic neuroma in the internal auditory meatus was not seen using virtual endoscopy. Although virtual MRI endoscopy has limitations, it provides 3D images which cannot be acquired using any other procedure.

Adolescent↗
PubMed1998

Rapid three-dimensional measuring system for facial surface structure.

A noncontact three-dimensional measuring system (liquid crystal range finder system) is described. Three-dimensional facial surface data (more than 30,000 points) could be obtained in 1 second, and the resolution was approximately 0.4 mm. The reliability and repeatability of the results were validated with a calibrating apparatus and a highly accurate contact-type three-dimensional digitizer. Consequently, the average of the measurement errors on a facial plaster model was 0.3 mm. Repeatability in measuring human faces was approximately 0.3 mm. Therefore, the total error in measuring human faces was approximately 0.5 mm. Because of the shortness of measuring time, this system was capable of scanning faces of infants without the need for sedation. The output of the liquid crystal range finder was demonstrated on an infant with cleft lip. The surface points improved by cheiloplasty, and the residual deformities were observed clearly. This system was thought to be the most suitable apparatus for measuring faces of infants (especially infants with cleft lip) and enabled us to analyze facial surface structure both qualitatively and quantitatively.

Adult↗
PubMed1998

CT angiography in vascular intervention for steno-occlusive diseases: role of multiplanar reconstruction and source images.

The aim of this study was to assess the efficacy of CT angiography for steno-occlusive diseases before and after interventional procedures, focusing on the role of multiplanar reconstruction (MPR) and source images. 17 patients with 20 steno-occlusive lesions underwent CT angiography before and after interventional procedures. For each lesion, the percentage stenosis obtained on CT angiography was compared with that on conventional angiography. In addition, MPR and source images were evaluated for the presence of wall thickening and calcification before interventional procedures, and the presence of dissection and luminal shape after interventional procedures. These findings were compared with those of conventional angiography. Although the percentage stenosis depicted on CT angiography correlated well with that on conventional angiography, MPR and source images clearly demonstrated the effect of intervention and the residual stenosis. MPR and source images clearly depicted wall thickening, wall calcification, the presence of dissection and the luminal shape. CT angiography provides useful information before intervention, while MPR and source images are of value in evaluating arterial wall abnormalities and morphological changes associated with interventional procedures.

Adult↗
PubMed1998

Inhibition of immunoglobulin production stimulating activity of glyceraldehyde-3-phosphate dehydrogenase by nucleotides.

We have previously identified glyceraldehyde-3-phosphate dehydrogenase as an immunoglobulin production stimulating factor (IPSF) which facilitated immunoglobulin production by hybridomas and lymphocytes. The IPSF activity of this enzyme was suppressed by the coexistence of some sorts of nucleotides. We now report that the IPSF effect of GAPDH was suppressed by the coexistence of DNA, the inhibiting effect of degraded DNA being inferior to that of long-chain DNA. Both single-stranded and double-stranded synthetic polyribonucleotides also inhibited the IPSF activity of GAPDH. Moreover, nicotinamide adenine dinucleotide (NAD+) repressed the IPSF effect.

Biological Factors↗
PubMed1998

Effects of presurgical orthopedic treatment in infants with complete bilateral cleft lip and palate.

OBJECTIVE: To align the protruding premaxilla in infants with bilateral cleft lip and palate (BCLP), an intraoral appliance (i.e., Hotz plate) and an extraoral appliance consisting of a band covering the head and elastics are used as a presurgical orthopedic treatment in our clinic. The aim of this study was to analyze the configuration and position of the premaxilla and the vomer in infants with BCLP and to investigate the factors generating deviation and bending of the vomer and twisting of the premaxilla. PATIENTS: Palatal casts were obtained serially from 10 infants with complete BCLP from 1 to 3 months of age. MEASUREMENTS: These casts were automatically measured using a highly accurate contact-type measuring apparatus. After three-dimensional wire frame models generated from the serial casts were automatically superimposed, the magnitude and direction of the shift were calculated. A discriminant analysis was used for investigation of predictor variables generating the twisting or bending vomer. RESULTS AND CONCLUSIONS: The vomer was found to be bent in two infants and the premaxilla was twisted in three infants. In the infants whose vomers were bent, the magnitude of the posterior shift of the premaxilla was greater than that of the inferior shift. A discriminant analysis indicated that at 1 month of age, a greater inclination and a smaller deviation of the vomer and a longer distance between the cleft edges of the lateral segments had a tendency to be associated with bending of the vomer or twisting of the premaxilla.

Cleft Lip↗
PubMed1998

Correlation of MR imaging-determined cerebral blood volume maps with histologic and angiographic determination of vascularity of gliomas.

OBJECTIVE: Our purpose was to evaluate the relationships between the ratio of maximum relative cerebral blood volume (rCBV) (rCBV ratio = rCBV[tumor]/rCBV[contralateral white matter]) and histologic and angiographic vascularities of gliomas using the gradient-echo echoplanar MR imaging technique. We also evaluated the usefulness of rCBV maps for grading gliomas. SUBJECTS AND METHODS: We examined 30 patients with histologically verified gliomas. Gliomas were classified as glioblastoma, anaplastic glioma with enhancement, anaplastic glioma without enhancement, and low-grade glioma. The maximum rCBV ratio of each glioma was compared with both histologic and angiographic vascularities, and the relationship between the maximum rCBV ratios and each type of glioma was established. RESULTS: The maximum rCBV ratios of the gliomas significantly correlated with both histologic and angiographic vascularities (p < .001). Mean values and SDs of maximum rCBV ratios of each type of tumor were 7.32+/-4.39 for glioblastomas, 5.84+/-1.82 for anaplastic gliomas with enhancement, 1.53+/-0.75 for anaplastic gliomas without enhancement, and 1.26+/-0.55 for low-grade gliomas. The maximum rCBV ratios of the glioblastomas were significantly higher than those of the anaplastic gliomas without enhancement (p = .002) and the low-grade gliomas (p < .001). The maximum rCBV ratios of the anaplastic gliomas with enhancement were higher than those of the anaplastic gliomas without enhancement and the low-grade gliomas, but the differences were not statistically significant (p = .08 and p = .03, respectively). CONCLUSION: The results of perfusion-sensitive MR imaging with gradient-echo echoplanar technique correlated with both histologic and angiographic vascularities.

Adolescent↗
PubMed1998

Inhibition in a microgravity environment of the recovery of Escherichia coli cells damaged by heavy ion beams during the NASDA ISS phase I program of NASA Shuttle/Mir mission no. 6.

We participated in a space experiment, part of the National Space Development Agency of Japan (NASDA) Phase I Space Radiation Environment Measurement Program, conducted during the National Aeronautics and Space Administration (NASA) Shuttle/Mir Mission No. 6 (S/MM-6) project. The aim of our study was to investigate the effects of microgravity on the DNA repair processes of living organisms in the in orbit. Heavy ion beam radiation- or ç-irradiation-damaged biological samples of Escherichia coli and the radioresistant bacterium Deinococcus radiodurans were prepared and placed in a biospecimen box, which was loaded into the RRMD III sensor unit of the Space Shuttle. Two identical sets of samples were left in the Spacehab's Payload Processing Facility (SPPF) in Florida, USA, as a control. (flight No. STS-84) was launched from NASA John F. Kennedy Space Center (KSC) in Florida, USA, on May 15, 1997. The mission duration was 9.22 days. An astronaut activated the biological samples in the biospecimen box in the Spacehab during orbit in order to start repair of the DNA damaged by heavy ion beams or ç-irradiation and the samples were incubated for 19 h 35 min at about 22ûC, the cabin temperature. The control specimens in the SPPF were subjected to the same treatment under terrestrial gravity. After returned to earth, we investigated cell recovery by comparing the repair of the radiation-damaged DNA of E. coli and D. radiodurans in the microgravity environment in space with that on Earth. The results indicated that the DNA repair process of E. coli, but not of D. radiodurans, cells was inhibited in a microgravity environment.

Cell Survival↗
PubMed1998

Three-dimensional FISP imaging in the evaluation of carotid cavernous fistula: comparison with contrast-enhanced CT and spin-echo MR.

PURPOSE: The purpose of this study was to assess the value of three-dimensional fast imaging with steady-state precession (FISP) MR sequences relative to contrast-enhanced CT and spin-echo MR imaging in the diagnosis of carotid cavernous fistula (CCF). METHODS: Seventeen patients with 19 angiographically proved CCFs had contrast-enhanced CT, spin-echo MR imaging, and 3-D FISP imaging. Three observers assessed these imaging studies as well as those of 43 control sides in a blinded manner for the presence or absence of CCF. Receiver operating characteristic analysis was used to assess the diagnostic utility of each imaging technique. In a nonblinded study, contrast-enhanced 3-D FISP images were also evaluated. RESULTS: Higher diagnostic accuracy was obtained with 3-D FISP sequences, as the shunt flow within the cavernous sinus was well seen. Sensitivity of 3-D FISP images was 83% and specificity was 100% in the blinded study. In the receiver operating characteristic analysis, the diagnostic performance of observers was found to be better with the 3-D FISP images than with the spin-echo MR images. Although there were no significant difference between 3-D FISP and contrast-enhanced CT, higher diagnostic performance was obtained with 3-D FISP images. In three CCFs without anterior drainage, a diagnosis was made only from the 3-D FISP images. The contrast-enhanced 3-D FISP images were not helpful, since the cavernous sinuses enhanced. CONCLUSION: Three-dimensional FISP imaging is superior to spin-echo MR imaging and contrast-enhanced CT in the diagnosis of CCF. Contrast-enhanced 3-D FISP images are not helpful for the evaluation of CCF.

Adolescent↗
PubMed1998

Contrast-enhanced T1-weighted three-dimensional gradient-echo MR imaging of the whole spine for intradural tumor dissemination.

BACKGROUND AND PURPOSE: When evaluating intradural tumor dissemination in the spine, contrast-enhanced T1-weighted 2D spin-echo (2D-SE) images are frequently problematic because most of the lesions are very small. Our purpose was to compare 2D-SE images with 3D gradient-echo (3D-GE) postcontrast images to determine which technique is better for depicting intradural tumor dissemination. METHODS: Ten patients with and 10 without intradural tumor dissemination were examined prospectively with MR imaging. After contrast administration, all patients underwent sagittal imaging with 2D-SE and 3D-GE sequences. Subsequently, the 2D-SE, 3D-GE, and multiplanar reconstruction (MPR) images of the 3D-GE sequence were evaluated for image quality, lesion detectability, signal-to-noise ratio (SNR), and contrast-to-noise ratio (CNR) of the disseminated lesions. RESULTS: Although delineation of spinal cord from CSF was slightly poorer on the 3D-GE sequences than on the 2D-SE sequences, the difference was not significant. In the evaluation of image artifacts and contrast between spinal cord and CSF, there was no significant difference. In seven patients with nodular enhancement, the 3D-GE sequence detected 46 lesions and the 2D-SE sequence detected 36. With MPR, the greatest number of lesions (n = 51) was detected, and vascular enhancement was clearly distinguished. There was no difference in SNR and CNR of lesions between the 3D-GE and 2D-SE sequences. CONCLUSION: The contrast-enhanced 3D-GE technique offers advantages over 2D-SE imaging in detecting intradural tumor dissemination, especially when the MPR technique is applied. This technique should be used for detecting intradural tumor dissemination.

Adolescent↗
PubMed1997

Design of stable biologically active recombinant lutropin analogs.

Glycoprotein hormones are noncovalent heterodimers comprised of a common alpha subunit and a hormone-specific beta subunit. Secretion and biologic action of these hormones are dependent on the formation of the heterodimer. The human LH beta subunit is unique among the other beta subunits in that it assembles inefficiently with the alpha subunit. To bypass this rate-limiting step, we constructed the LH single chains where the carboxy terminus of beta was fused to the amino terminus of alpha subunit through a linker. Compared to the human LH heterodimer, the extent of secretion was greater for the tethers although the rate was dependent on the nature of the linker. The LH single chains were biologically active even though there was loss of recognition by a LH-specific monoclonal antibody. This suggests that receptor binding of the single chains is not impaired by changes in the heterodimeric configuration resulting from tethering the subunits. In addition, single chains exhibited a remarkably greater in vitro stability than the heterodimer, implying that these analogs will be useful as diagnostic reagents and that their purification will be facilitated.

Animals↗
PubMed1997

Palatal configuration in complete bilateral cleft lip and palate infants before and after cheiloplasty.

OBJECTIVE: The purpose of this study was to analyze the three-dimensional configuration of the premaxilla, vomer, and lateral segments in bilateral cleft lip and palate (BCLP) infants and to investigate the early changes in the configuration following one- and two-stage cheiloplasty. METHODS: This study consisted of 10 complete BCLP infants. One-stage operations were performed in five patients according to Manchester's method at 4 months of age. Two-stage operations were done for the remaining five patients using a triangular flap according to Tennison's method, at 4 and 8 months of age. Serial plaster models before and after the cheiloplasty were measured with a computer-controlled, highly accurate, contact-type measuring apparatus. Temporal changes in the configuration and form of the premaxilla were observed using an automatic superimposition method. The inclination and deviation of the vomer were evaluated using an approximation technique to a straight line with least squares. The distance between the lateral segments and a three-dimensional coordinate of the incisal point were also measured. RESULTS AND CONCLUSIONS: The following differences in palatal configuration between the one- and two-stage cheiloplasties were observed: 1) In the two-stage group, the premaxilla shifted toward the cleft edge where the cheiloplasty was performed in both first- and second-stage operations. After the two-stage operation, the premaxilla did not shift greatly, and the premaxilla in cases 4 and 5 shifted downward and toward the cleft edge of the lateral segments where the first operation was performed. Protrusion of the premaxilla remained in the two-stage group. 2) In the one-stage group, the premaxilla in case 4 descended downward and backward without twisting or bending. The premaxilla of the other patients descended downward with twisting and bending. 3) Patients in the two-stage group had a stronger tendency toward medial collapse of the lateral segments than did those in the one-stage group.

Calcium Sulfate↗
PubMed1997

Comparison of HASTE and segmented-HASTE sequences with a T2-weighted fast spin-echo sequence in the screening evaluation of the brain.

OBJECTIVE: The purpose of this study was to evaluate the neuroradiologic application of half-Fourier acquisition single-shot turbo spin-echo (HASTE) and segmented-HASTE (s-HASTE) sequences in comparison with a T2-weighted fast spin-echo sequence. MATERIALS AND METHODS: First, HASTE, s-HASTE, and fast spin-echo sequences were evaluated for blurring artifacts with a stationary phantom and for motion artifacts with a moving phantom, which repeated constant or intermittent to-and-fro motions at variable intervals. Second, 30 consecutive patients with various intracranial diseases were prospectively examined with the three sequences. Lesions were classified into four groups according to size and signal intensity on fast spin-echo MR images as follows: large hyperintense, small hyperintense, small markedly hyperintense, and hypointense lesions. Signal intensities of the lesion, putamen, and gray matter were compared with the signal intensity of white matter, and contrast-to-noise ratios were calculated. Overall image quality, conspicuity of lesions, delineation of the junction between gray matter and white matter, conspicuity of the putamen, and certain types of artifacts were evaluated qualitatively. RESULTS: In the phantom study, the HASTE sequence was least affected by motion artifacts and the fast spin-echo sequence was most affected although the images of the HASTE sequence were most degraded by blurring artifacts. In the clinical study, we found no significant differences among the three sequences for contrast-to-noise ratios or conspicuity of large hyperintense and small markedly hyperintense lesions. However, the contrast-to-noise ratios of hypointense lesions and gray matter, and the conspicuity of hypointense lesions were significantly poorer for the HASTE sequence than for the fast spin-echo sequence. The contrast-to-noise ratios of small hyperintense lesions and the putamen, conspicuity of small hyperintense lesions and putamen, and delineation of the junction between gray matter and white matter were significantly poorer for HASTE and s-HASTE sequences than for the fast spin-echo sequence. Ghost artifacts, which were observed during the s-HASTE sequence, were sometimes superimposed on the image. CONCLUSION: The HASTE and s-HASTE sequences afford substantial time reduction and also decrease motion artifacts and thus have potential advantages for neuroradiologic application, especially in uncooperative or unsedated children. The s-HASTE sequence may be preferable to the HASTE sequence because of fewer blurring artifacts and higher T2 contrast. However, small hyperintense and hypointense lesions may be overlooked when HASTE and s-HASTE sequences are used.

Artifacts↗
PubMed1997

Evaluation of intracranial lesions with inversion recovery half-Fourier single-shot turbo spin-echo MR: initial observations.

PURPOSE: To determine the value of inversion recovery half-Fourier single-shot turbo spin-echo (IR-HASTE) MR sequences in the characterization of a variety of intracranial lesions, with the focus on differentiating between epidermoids and nonneoplastic cystic lesions. METHODS: We used a 1.5-T MR unit to study five epidermoids, seven arachnoid cysts, seven other nonneoplastic cysts (three neuroepithelial cysts, two interhemispheric cysts, and two Rathke's cleft cysts), and eight solid neoplasms (three meningiomas, two astrocytomas, one subependymoma, one cavernoma, and one metastatic tumor) using IR-HASTE sequences with variable inversion times (TI). Imaging time for each section was 2 seconds for the sequence. The TI nulling values were analyzed statistically. RESULTS: The TI nulling values were 1200 to 2300 for the epidermoids, 2800 to 3000 for the arachnoid cysts, 300 and 800, respectively, for the Rathke's cleft cysts, 2500 to 3000 for the other nonneoplastic cysts, and 300 to 1500 for the solid neoplasms. There was no overlap of TI nulling values between the arachnoid cysts and the epidermoids; the difference was statistically significant. Both patients with interhemispheric cysts had two lesions in which the TI nulling values were different. CONCLUSION: IR-HASTE sequences provide a rapid and reliable imaging method for differentiating among epidermoids, arachnoid cysts, and solid neoplasms. This technique also provides information about the continuity of the multicystic lesions in terms of the differences in their TI nulling values. For solid intraaxial masses, the use of IR-HASTE helps to differentiate intratumoral cysts and necrosis from solid components.

Adolescent↗
PubMed1997

T2 shortening in the visual cortex: effect of aging and cerebrovascular disease.

PURPOSE: To evaluate the effect of aging and cerebrovascular disease on T2 shortening in the visual cortex at MR imaging. METHODS: MR images of 72 neurologically normal subjects (45 men and 27 women, 35 to 92 years old) and 32 (13 men and 19 women, 54 to 92 years old) with cerebrovascular disease were evaluated retrospectively. On T2-weighted spin-echo images, the signal intensity of the visual, motor, and sensory cortices was divided into three grades and compared with the signal intensity of the frontal subcortical white matter. RESULTS: Decreased signal intensity (grade III) was rarely seen in the visual and sensory cortices of the neurologically normal subjects who were less than 60 years old. The signal intensity of the motor cortex decreased rapidly after the age of 50 years. At 61 to 70 years of age, 53% of these subjects had grade III intensity, and at age 71 years or older, 94% had reached grade III. The frequency of progression from grade I to grade III was lower in the visual cortex than in the motor cortex; 22% of these subjects had grade III appearance at age 61 to 70 years, and at age 71 years older, 56% had reached grade III. In patients with cerebrovascular disease who were older than 60 years of age, the frequency of grade III signal intensity in the visual cortex was almost equal to that in the neurologically normal subjects. CONCLUSIONS: T2 shortening in the visual cortex is frequently seen in neurologically normal older persons. These findings are compatible with a previously reported histochemical study of normal iron deposition in the visual cortex. Cerebrovascular disease has no effect on T2 shortening in the visual cortex.

Adult↗