To evaluate the efficacy of STIR (short tau inversio recovery) image in the diagnosis of orbital diseases, we compared the STIR images with conventional SE(spin-echo) images in 17 patients. The fat signal was reliably nulled at inversion time of approximately 160-170 msec in all cases. We analyzed all the cases in the aspects of the detection of lesion and the lesion-to-back ground contrast retrospectively. Regarding lesion, the detection rates of STIR, T1 and T2-weighted images were 89, 88 and 83% respectively. In the aspect of lesion-to-background contrast, the contrast ratios of STIR and T1, T2-weighted image were 87% and 64, 56%, respectively. In conclusion, STIR images were similar to T1-and T2-weighted images in the detection of lesion, but superior in the aspect of lesion-to-background contrast. So the STIR images may be a useful adjunct to conventional SE images for the diagnosis of orbital disease.
Diagnosis* ; Humans ; Orbit* ; Orbital Diseases* ; Retrospective Studies

Diabetes insipidus(DI) of central origin is a clinical syndrome resulting from low blood levels of antidiuretic hormone secreted from the posterior lobe of the pituitary gland, which is usually caused by lesions involving the hypothalamus-neurohypophyseal axis. MR imaging can reveal absence of the posterior pituitary bright signal(PPBS)in DI. The authors reviewed four patients with intracranial germinomas who had DI due to hypothalamus involvement. All patients before radiotherapy revealed absence of PPBS on MRI. Three cases recovered from DI after radiotherapy and showed reappearance of PPBS. Another one patients who continued DI didn't show signal change of the posterior pituitary gland. Ws speculated that the reappearance of PPBS is related to clinical improvement of DI.
Diabetes Insipidus* ; Follow-Up Studies* ; Germinoma* ; Humans ; Hypothalamus ; Magnetic Resonance Imaging ; Pituitary Gland ; Pituitary Gland, Posterior ; Radiotherapy*

PURPOSE: To investigate the localization and functional lateralization of the supplementary motor area (SMA) in motor activation tests in comparison to that of the primary motor area. MATERIALS AND METHODS: Seven healthy volunteers obtained echoplanar imaging blood oxygen level dependent technique. This study was carried on 1.5T Siemens Magneton Vision system with the standard head coil. Parameters of EPI were followed as ; TR/TE; 1.0/66.0 msec. flip angle : 90degree, field of view : 22cmx22cm, matrix : 128x128, slice number/slice thickness/gap : 10/4mm/0.8mm with fat suppression technique. Motor task as finger opposition in each hand consisted of 3 sets of alternative rest and activation periods. Postprocessing were done on Stimulate 5.0 by using cross-correlation statistics. To compare the functional lateralization of the SMA in the right and left hand tests, each examination was evaluation for the percent change of signal intensity and the number of activated voxels both in the SMA and in the primary motor area. Hemispheric asymmetry was defined as difference of summation of the activated yokels between each hemisphere. RESULTS: Percent change of signal intensity in the SMA (2.49-3.06%) is lower than that of primary motor area(4.4-7.23%). Percent change of signal intensity including activated voxels were observed almost equally in the right and left SMA. As for summation of activated voxels primary motor area had significant difference between each hemisphere but not did the SMA. CONCLUSION: Preferred contralateral dominant hemisphere and hemispheric asymmetry were detected in the primary motor area but not in the SMA.
Echo-Planar Imaging ; Fingers ; Hand* ; Head ; Healthy Volunteers ; Magnetic Resonance Imaging* ; Oxygen

No abstract available.
Adult ; Biopsy ; Brain ; Child ; Deception ; Dermis ; Facial Bones ; Female ; Hair ; Humans ; Melanins ; Neurofibromatoses* ; Scalp ; Skin ; Temporal Muscle ; Zygoma

The real time high resolution mechanical neurosonographic sector scanner is a convenient and useful instrumentfor detection of intracranial lesions in premature infants as well as low birth weight. From this experience,authors report with 104 neonates and infants who had been suspected intracranial hemorrhage and had been detectedand graded by sonography. The results were as followed: 1. The incidence of intracranial hemorrhage is 20 of 46(43.5%) neonates who had been studied before 3 days of age. But 7 of 16(43.7%) neonates showed ICH between the 4-7days of age. 2. There was no difference of prevalence in sex ratio in neonates with ICH. 3. There was closerelationship between ICH and gestational weeks. 15 of 27 (55.6%) neonates who were born under 32 gestational weeksshowed ICH was graded as 3 or 4 in 7 of 10. 4. 10 of 16(62.5%) neonate who were born under 1,500 gram body weighthad ICH within first 4 days. The severity of ICH was graded as 3 or 4 in 7 of 10. 5. The mode of deliveryinfluenced neonatal ICH incase of difficulty delivery such as forcep(4/4, 100%), vacuum (7/10, 70%), breech (3/3,100%), and C/S(13/33, 39.4%). 6. Incidence of ICH in neonates with pathologica lung conditions (29/40, 72.5%) washigher than ICH with normal chest findins(15/64, 23.4%). 7. For frequent follow up study of brain, neurosonographywas very helpul and economic in case of ICH, and could find congenital glioblastoma multiformed(1), and low gradeastrocytoma(1) incidentally.
Brain ; Follow-Up Studies ; Glioblastoma ; Humans ; Incidence ; Infant ; Infant, Low Birth Weight ; Infant, Newborn ; Infant, Premature ; Intracranial Hemorrhages ; Lung ; Prevalence ; Sex Ratio ; Thorax ; Vacuum

PURPOSE: To elucidate the incidence of Gd-DTPA enhancement of the optic nerve/sheath complex (ONC) in patients with various ophthalmopathies using fat-suppression MRI. MATERIALS AND METHODS: Orbit MRI with fat-suppression technique (ChemSat) was performed in 58 patients with normal and various orbital lesions. The fat-suppression MR was done with and without Gd-DTPA injection in all cases. MR findings were reviewed retrospectively in a blind fashion with respect to presence or absence of contrast enhancement of the O NC. RESULTS: Contrast enhancement of the ONC was seen in 86% (6/7) of cavernous sinus lesions, 80% (8/10) of intraconal lesions excluding the ONC, 57% (16/28) of ONC lesions, 38% (3/8) of ocular lesions, and 2% (1/55) of normal orbits. The ONC enhancement was the most common in optic nerve/sheath tumors (10/10), and pseudotumors (6/6), cavernous sinus dural arteriovenous malformations (3/3) and cavernous sinus thrombosis (2/2), and less frequently seen in optic neuritis (3/14). CONCLUSION: Enhancement of the ONC may be seen in lesions of the cavernous sinusand orbit other than optic nerve/sheath lesion.
Arteriovenous Malformations ; Cavernous Sinus ; Cavernous Sinus Thrombosis ; Gadolinium DTPA ; Humans ; Incidence* ; Magnetic Resonance Imaging* ; Optic Neuritis ; Orbit* ; Retrospective Studies

PURPOSE: To evaluate the value of fast field echo(FE) technique in accesing temporOmandibular joint(TMJ) dynamics. MATERIALS AND METHODS: A series of 120 TMJ MRI examinations of 60 symptomatic patients was performed. The fast FE technique was used to provide dynamic images of the TMJs in various phase of mouth opening with a step-bite-block. RESULTS: Among 120 cases, there were 30 cases which were normal, 21 cases of anterior displacement with reduction, 66 cases of anterior displacement without reduction, 11 cases of deformity of menisci, 23 cases of bony deformity, and 3 cases of medial displacement. The menisci and condyles were clearly delineated and the motions of the menisci during jaw opening were well evaluated in both normal and pathologic conditions. CONCLUSION: The dynamic TMJ MRI scan using fast FE technique permits both fast scanning and study of joint dynamics as well as TMJ anatomy.
Congenital Abnormalities ; Humans ; Jaw ; Joints ; Magnetic Resonance Imaging* ; Mouth ; Temporomandibular Joint*

PURPOSE: Functional MR imaging is the method of demonstrating changes in regional cerebral blood flow produced by sensory, motor, and any other tasks. Functional MR of visual cortex os performed as a patient stares a photic stimulation, so adaptable photic stimulation is necessary. The purpose of this study to evaluate whether the size of photic stimulation can affect the degree of visual cortex activation. MATERIALS AND METHODS: Functional MR imaging was performed in 5 volunteers with normal visual acuity. Photic stimulator was made by 39 light-emitting diodes on a plate ,operating at 8 Hz. The sizes of photic stimulator were full field, half field and focal central field. The MR imager was Siemens 1.5-T Magenton Vision system, using standard head coil. Functional MRI utilized EPI sequence (TR/TE=1.0/51. 0msec, matrix No.=98x128, slice thickness=8mm) with 3sets of 6 imaging during stimulation and 6 imaging during stimulation and 6 imaging during rest, all 36 scanning were obtained. Activated images were obtained using postprocessing software(statistical analysis by Z-zone, and these images were combined with T-1 weighted anatomical images. The activated signals were quantified by numbering the activated pixels, and activation index was obtained by dividing the pixel number of each stimulator size with the sum of the pixel number of 3 study using 3 kinds of stimulators. The correlation between the activation index and the stimulation size was analysed. RESULTS: Mean increase of signal intensities on the activation area using full field photic stimulator was about 9.6%. The activation index was greatest on full field. second on half field and smallest in focal central field in 4, The index of half field was greater than that of full field in 1. The ranges of activation index were full field 43-73%(mean 55%), half field 22-40%(mean 32%), and focal central field 5-24%(13%). CONCLUSION: The degree of visual cortex activation increases with the size of photic stimulator.
Head ; Humans ; Magnetic Resonance Imaging* ; Photic Stimulation ; Visual Acuity ; Visual Cortex* ; Volunteers

No abstract available.

No abstract available.
Cytomegalovirus* ; DNA* ; Humans* ; Polymerase Chain Reaction*