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At least 613 records · Page 34Linked to original sources
PubMed2005

Clinical utility of sonography in diagnosing plantar fasciitis.

OBJECTIVE: The purpose of this study was to investigate the efficacy of sonography in the detection of plantar fasciitis (PF) compared with magnetic resonance imaging (MRI) findings in subjects with inferior heel pain. METHODS: Seventy-seven patients with unilateral (n = 9) and bilateral (n = 68) heel pain were studied. Seventy-seven age- and sex-matched asymptomatic subjects served as a control group. Magnetic resonance imaging was used to establish a diagnosis of PF with sagittal T1-weighted, T2-weighted, and short tau inversion recovery sequences. The sonographic appearances of PF were compared with MRI findings. Plantar fascia and heel pad thickness were also measured on both imaging modalities. RESULTS: Compared with MRI, sonography showed 80% sensitivity and 88.5% specificity in assessing PF. A strong correlation was found between plantar fascia and fat pad thickness measurements done by sonography (P < .001; r = 0.854) and MRI (P < .001; r = 0.798). Compared with the asymptomatic volunteers, patients with PF had significant increases in plantar fascia and heel pad thicknesses, weight, and body mass index (P = .0001). Heel pad thickness was also significantly increased with pain duration (P = .021). CONCLUSIONS: Although MRI is the modality of choice in the morphologic assessment of different plantar fascia lesions, sonography can also serve as an effective tool and may substitute MRI in the diagnosis of PF.

Adult↗
PubMed1999

[Fundamental study of the detection of metastatic bone tumors with whole-body MR imaging].

Preliminary studies were performed to evaluate the usefulness of whole-body magnetic resonance imaging (WB-MRI) in the screening of bone metastases. The fast short TI inversion recovery sequence was the most suitable method because of its minimal image distortion and uniformity of fat suppression in a large field of view. In 4 cases of malignant tumor, the localization of all 8 bone metastases detected with bone scintigraphy (BS) could be clarified with WB-MRI. Furthermore, WB-MRI with fast STIR alone could depict 4 lesions undetected by BS, and WB-MRI combined with contrast enhancement could depict 5 such lesions.

Bone Neoplasms↗
PubMed1999

The MR imaging assessment of submandibular gland sialoadenitis secondary to sialolithiasis: correlation with CT and histopathologic findings.

BACKGROUND AND PURPOSE: MR imaging has been proved to be effective in depicting wide variety of pathologic changes of the salivary gland. Therefore, we evaluated clinical usefulness of MR imaging for sialolithiasis. METHODS: Sixteen patients with sialolithiasis of the submandibular gland underwent MR imaging. MR images of the glands were obtained with a conventional (T1-weighted), fast spin-echo (fat-suppressed T2-weighted) and short inversion time-inversion recovery sequences. Contrast enhancement was not used. MR imaging features then were compared with clinical symptoms, histopathologic features of excised glands, and CT imaging features. RESULTS: Submandibular glands with sialolithiasis could be classified into three types on the basis of clinical symptoms and MR imaging features of the glands. Type I glands were positive for clinical symptoms and MR imaging abnormalities, and were characterised histopathologically by active inflammation (9 [56%] of 16). Type II glands were negative for clinical symptoms and positive for MR imaging abnormalities (4 [25%] of 16), and the glands were replaced by fat. Type III glands were negative for clinical symptoms and MR imaging abnormalities (3 [19%] of 16). CT features of these glands correlated well with those of MR imaging. CONCLUSION: These results suggest that MR imaging features may reflect chronic and acute obstruction, and a combination of CT and MR imaging may complement each other in examining glands with sialolithiasis.

Adipose Tissue↗
PubMed2000

Does diving damage the brain? MR control study of divers' central nervous system.

PURPOSE: To evaluate the prevalence of cerebral white matter changes on MR imaging in healthy elderly compressed air divers with a long diving history in comparison with control subjects who have never dived. MATERIAL AND METHODS: The investigation employed 59 experienced elderly divers and 48 control subjects matched for age, body mass index, alcohol and smoking history. MR studies included a fluid attenuated inversion recovery sequence and T1- and T2-weighted pre- and postcontrast images in axial orientation of the whole brain to localize white matter changes. RESULTS: MR images did not show any morphologic abnormalities in the brains of divers. Both groups - divers and controls - did not differ significantly with respect to white matter changes of the brain. CONCLUSION: No increased prevalence of cerebral white matter changes in compressed air divers compared with a healthy worker sample of similar age were found. Thus, extensive compressed air diving may not necessarily be related to radiological changes on MR.

Adult↗
PubMed2000

Unbalanced X-chromosome inactivation with a novel FVIII gene mutation resulting in severe hemophilia A in a female.

This report is of a 14-month-old girl affected with severe hemophilia A. Both her parents had normal values for factor VIII activity, and von Willebrand disease type 2N was excluded. Karyotype analysis demonstrated no obvious alteration, and BclI Southern blot did not reveal F8 gene inversions. Direct sequencing of F8 gene exons revealed a frameshift-stop mutation (Q565delC/ter566) in the heterozygous state in the proposita only. F8 gene polymorphism analysis indicated that the mutation must have occurred de novo in the paternal germline. Furthermore, analysis of the pattern of X chromosome methylation at the human androgen receptor gene locus demonstrated a skewed inactivation of the derived maternal X chromosome from the lymphocytes of the proband's DNA. Thus, the severe hemophilia A in the proposita results from a de novo F8 gene frameshift-stop mutation on the paternally derived X chromosome, associated with a nonrandom pattern of inactivation of the maternally derived X chromosome. (Blood. 2000;96:4373-4375)

Child, Preschool↗
PubMed2001

[An operated case of bitemporal lobe epilepsy associated with old infarction in the left occipital lobe].

A 15-year-old female, who presented with bitemporal lobe epilepsy associated with old infarction in the left occipital lobe, was reported. MRI with fluid attenuated inversion recovery sequence demonstrates cortical atrophy with hyperintensity of the white matter in the left occipital lobe as well as volume loss and hyperintensity of the left hippocampus. Interictal positron emission tomography with [18F]fluorodeoxy glucose (FDG-PET) and single photon emission computed tomography with technetium-99m-ethyl-cysteinate dimer indicate hypometabolism and hypoperfusion in the left occipital lobe and the left temporal lobe, respectively. Scalp recorded EEG did not lateralize the side of the epileptogenic zone. Chronic subdural electrode recording demonstrated that the ictal onset zones were located in the bilateral side of the temporal lobe. Eighty-nine percent of 19 spontaneous seizures were left sided onset. The anterior temporal lobectomy with hippocampectomy was performed for the left side. Although temporal lobe epilepsy is sometimes a bilateral disease, unilateral lobectomy for a strong predominant side, based on the MRI and FDG-PET findings, is effective for some patients.

Adolescent↗
PubMed2001

The value of MR neurography for evaluating extraspinal neuropathic leg pain: a pictorial essay.

SUMMARY: Fifteen patients with neuropathic leg pain referable to the lumbosacral plexus or sciatic nerve underwent high-resolution MR neurography. Thirteen of the patients also underwent routine MR imaging of the lumbar segments of the spinal cord before undergoing MR neurography. Using phased-array surface coils, we performed MR neurography with T1-weighted spin-echo and fat-saturated T2-weighted fast spin-echo or fast spin-echo inversion recovery sequences, which included coronal, oblique sagittal, and/or axial views. The lumbosacral plexus and/or sciatic nerve were identified using anatomic location, fascicular morphology, and signal intensity as discriminatory criteria. None of the routine MR imaging studies of the lumbar segments of the spinal cord established the cause of the reported symptoms. Conversely, MR neurography showed a causal abnormality accounting for the clinical findings in all 15 cases. Detected anatomic abnormalities included fibrous entrapment, muscular entrapment, vascular compression, posttraumatic injury, ischemic neuropathy, neoplastic infiltration, granulomatous infiltration, neural sheath tumor, postradiation scar tissue, and hypertrophic neuropathy.

Adolescent↗
PubMed2001

CT and MR imaging features of pyogenic ventriculitis.

BACKGROUND AND PURPOSE: Pyogenic ventriculitis is an uncommon manifestation of severe intracranial infection that might be clinically obscure. We hypothesized that determining characteristic imaging features of pyogenic ventriculitis in patients with appropriate risk factors might improve recognition of this severe infection. METHODS: Review of the medical records from 1990 to 2000 revealed 17 cases (12 men, five women) that satisfied inclusion criteria of abscess (n = 3) and/or positive cultures or increased white cells and protein in ventricular (n = 12) or cisternal (n = 1) cerebrospinal fluid. In one case, the diagnosis of ventriculitis was based on the combination of bacterial growth in lumbar cerebrospinal fluid and follow-up imaging. Staphylococcus species and Enterobacter species were the most common organisms. Two neuroradiologists independently evaluated imaging studies for hydrocephalus, ventricular debris, periventricular attenuation or signal abnormality, ependymal enhancement, and signs of meningitis or abscess. Sixteen studies in 11 patients were performed after the intravenous administration of contrast material. RESULTS: Ventricular debris was detected in 16 (94%) of 17 cases and was irregular in 13 (81%) of 16 cases. Hydrocephalus was present in 13 (76%) of 17 cases. Periventricular hyperintense signal was present in most (seven [78%] of nine) cases with MR imaging and was most conspicuous on fluid-attenuated inversion recovery sequences. Ependymal enhancement was detected in seven (64%) of 11 cases in which contrast material was administered. Signs of meningitis (eg, pial or duraarachnoid signal abnormality or enhancement) were present in 13 (76%) of 17 cases. Three cases had imaging signs of abscess. CONCLUSION: Ventricular debris was the most frequent sign of ventriculitis in this series. An irregular level was characteristic of debris in ventriculitis. Hydrocephalus and ependymal enhancement were less frequent signs. Detection of ventricular debris might facilitate diagnosis of pyogenic ventriculitis, a potentially fatal infection, and thus permit appropriate therapy.

Adult↗
PubMed2002

Erythropoietin therapy for acute stroke is both safe and beneficial.

BACKGROUND: Erythropoietin (EPO) and its receptor play a major role in embryonic brain, are weakly expressed in normal postnatal/adult brain and up-regulated upon metabolic stress. EPO protects neurons from hypoxic/ ischemic injury. The objective of this trial is to study the safety and efficacy of recombinant human EPO (rhEPO) for treatment of ischemic stroke in man. MATERIALS AND METHODS: The trial consisted of a safety part and an efficacy part. In the safety study, 13 patients received rhEPO intravenously (3.3 X 10(4) IU/50 ml/30 min) once daily for the first 3 days after stroke. In the double-blind randomized proof-of-concept trial, 40 patients received either rhEPO or saline. Inclusion criteria were age <80 years, ischemic stroke within the middle cerebral artery territory confirmed by diffusion-weighted MRI, symptom onset <8 hr before drug administration, and deficits on stroke scales. The study endpoints were functional outcome at day 30 (Barthel Index, modified Rankin scale), NIH and Scandinavian stroke scales, evolution of infarct size (sequential MRI evaluation using diffusion-weighted [DWI] and fluid-attenuated inversion recovery sequences [FLAIR]) and the damage marker S100ss. RESULTS: No safety concerns were identified. Cerebrospinal fluid EPO increased to 60-100 times that of nontreated patients, proving that intravenously administered rhEPO reaches the brain. In the efficacy trial, patients received rhEPO within 5 hr of onset of symptoms (median, range 2:40-7:55). Admission neurologic scores and serum S100beta concentrations were strong predictors ofoutcome. Analysis of covariance controlled for these two variables indicated that rhEPO treatment was associated with an improvement in follow-up and outcome scales. A strong trend for reduction in infarct size in rhEPO patients as compared to controls was observed by MRI. CONCLUSION: Intravenous high-dose rhEPO is well tolerated in acute ischemic stroke and associated with an improvement in clinical outcome at 1 month. A larger scale clinical trial is warranted.

Blood Platelets↗
PubMed2003

Brain microembolism.

PURPOSE: To alert clinicians about the occurrence of a subtype of brain infarction, its suspected etiology, and its detection by specific neuroimaging techniques. METHODS: The article presents 5 nonconsecutive patients admitted to the stroke services of 2 tertiary care hospitals, who presented with acute or subacute symptoms suspicious, but at times atypical, of brain ischemia. FINDINGS: Each patient had evidence of 3 to > 20 small areas of recent brain infarction detected by diffusion-weighted imaging (DWI). When available, brain computerized tomography images were not helpful for the diagnosis of these recent infarcts. Most lesions were present on magnetic resonance imaging fluid-attenuated inversion recovery sequences, but the diffusion-weighted images allowed the determination of their acuity. Further evaluation revealed a potential source of embolism in each patient. Brain microembolism was suspected in all cases. CONCLUSION: Small and multiple areas of acute or subacute brain infarction occasionally present with clinical features atypical for brain embolism. They can be detected by magnetic resonance DWI studies.

Aged↗
PubMed2003

Thalamic involvement in sporadic Creutzfeldt-Jakob disease: a diffusion-weighted MR imaging study.

BACKGROUND AND PURPOSE: Recent neuropathologic research suggests thalamic involvement in sporadic Creutzfeldt-Jakob disease (sCJD), which has been disregarded in imaging studies. Diffusion-weighted (DW) MR imaging has the highest sensitivity for the detection of signal intensity (SI) abnormalities in CJD. We hypothesized that pathologic changes in the thalamus in sCJD can be detected by using a subtle analysis of DW MR imaging. METHODS: Six sCJD patients and nine healthy controls were examined with a 1.5-T system by using DW single-shot spin-echo echo planar (b = 0, 1000 s/mm(2)), T2-weighted turbo spin-echo, and fluid-attenuated inversion recovery sequences. One patient was examined serially (3, 4, and 8 months after onset of symptoms). MR images were reviewed for SI changes in the striatum, hippocampus, mediodorsal thalamic nucleus (MD), and pulvinar thalami. Apparent diffusion coefficients (ADCs) were measured in these areas. RESULTS: All sCJD patients showed increased SI on DW images in the striatum bilaterally. ADCs in these areas were significantly reduced. Four of six sCJD patients showed increased SI on DW images in the pulvinar thalami, whereas ADCs were significantly reduced in all patients (mean ADC +/- SEM: in patients with SI changes, 701 +/- 38; in patients without SI changes, 684 +/- 37; in controls, 853 +/- 15 [P <.0001]). No patient showed SI changes in the MD on DW images, whereas ADCs were significantly reduced in all (664 +/- 28 as compared with 800 +/- 24 in controls [P =.0011]). Serial measurements in one sCJD patient showed ADC reduction in the pulvinar thalami preceding the SI changes on DW images. CONCLUSION: A quantitative analysis of DW images with ADC measurements shows slight MR imaging changes in the thalamus in sCJD when abnormal SI may not be present.

Aged↗
PubMed1992

[A case of foreign-body granuloma treated with steroid hormone].

A 68-year-old woman was admitted to Nagasaki University Hospital complaining of gait disturbance. She had suffered from hemifacial spasm since the age of 56 and had undergone neurovascular decompression for the spasm in another hospital five years before admission. At surgery, the vertebral and posterior inferior cerebellar arteries had been separated from the facial nerve with cotton string and attached to the clivus with alpha-cyanoacrylate monomer. Although the hemifacial spasm had improved postoperatively, the patient had suffered from gait disturbance and headache for two months after surgery, and hearing disturbance and hemifacial palsy on the same side as the hemifacial spasm for seven months after surgery. At the time of the present admission, contrast-enhanced CT scan revealed a mass at the left cerebello-pontine angle. In the T1-weighted inversion recovery sequence of MRI, the mass showed a slightly lower intensity than that of surrounding tissues. In the T2-weighted spin echo sequence of MRI, it showed a heterogenously low intensity with some high intensity spots. We diagnosed this mass as a foreign-body granuloma and treated it with dexamethasone injected intramuscularly. Edema decreased around the granuloma, and her gait disturbance improved markedly. But the hearing disturbance and hemifacial palsy did not improve at all, indicating that these two symptoms might not be caused only by brain edema but also by direct damage due to granuloma or inflammation. We thought that the steroid hormone elicited good results in the treatment of inoperable foreign-body granuloma.

Aged↗
PubMed2003

Association between right-to-left shunts and brain lesions in sport divers.

BACKGROUND: Recent studies suggest that healthy sport divers may develop clinically silent brain damage, based on the association between a finding of multiple brain lesions on MRI and the presence of right-to-left shunt, a pathway for venous gas bubbles to enter the arterial system. METHODS: We performed echocontrast transcranial Doppler sonography in 42 sport divers to determine the presence of a right-to-left shunt. Cranial MRI was carried out using a 1.5 T magnet. A lesion was counted if it was hyperintense on both T2-weighted and T2-weighted fluid attenuated inversion recovery sequences. To test the hypothesis that the occurrence of postdive arterial gas emboli is related to brain lesions on MRI, we measured postdive intravascular bubbles in a subset of 15 divers 30 min after open water scuba dives. RESULTS: Echocontrast transcranial Doppler sonography revealed a right-to-left shunt in 16 of the divers (38%). Only one hyperintensive lesion of the central white matter was found and that was in a diver with no evidence of a right-to-left shunt. Postdive arterial gas emboli were detected in 3 out of 15 divers; they had a right-to-left shunt, but no pathologic findings on cranial magnetic resonance imaging. CONCLUSIONS: Our data support the theory that right-to-left shunts can serve as a pathway for venous gas bubbles into the arterial circulation. However, we could not confirm an association between brain lesions and the presence of a right-to-left shunt in sport divers.

Adult↗
PubMed2003

Cerebral infarction in a 24-year-old pilot.

Ischemic stroke is a rare event in young adults. We report on a 24-yr-old pilot with cerebral infarction of undetermined etiology, temporally associated with chain smoking. The patient exhibited dysphasia, stupor (confused consciousness), and right facial-nerve palsy. Computed-tomography revealed a low-density area in the left insular cortex. Cerebroangiography showed severe stenosis in a branch of the left middle cerebral artery. After admission, the patient made a rapid and uneventful recovery within 72 h. MRI showed an area of hyperintensity on T2-weighted images 2 mo after the attack. Based on the hyperintense area on FLAIR (fluid attenuated inversion recovery sequence) images obtained in MRI performed 10 mo after the attack, we diagnosed a cerebral infarction. In the Japan Air Self-Defense Force, cerebral infarction is an aeromedically disqualifying condition. However, in the evaluation 2 mo after the attack, differentiation from reversible ischemic neurological deficit was difficult. We discuss the criteria used for diagnosis and the risk factors for cerebral infarction in young adults, as well as the aeromedical disposition of young pilots.

Adult↗
PubMed1992

Technical advances in magnetic resonance imaging.

Magnetic resonance (MR) imaging continues to develop at a rapid rate. Major new innovations include functional neuroimaging, fast spin-echo, magnetization transfer, the fluid attenuated inversion recovery sequence, MR angiography and measurement of cerebrospinal fluid (CSF) flow. Further developments of functional imaging and interventional techniques are expected.

Central Nervous System↗
PubMed2004

Noninvasive MR cisternography with fluid-attenuated inversion recovery and 100% supplemental O(2) in the evaluation of neurocysticercosis.

SUMMARY: We describe an MR protocol for the noninvasive imaging of the subarachnoid space, which we use in patients with suspected neurocysticercosis in this space. It consists of a fluid-attenuated inversion recovery sequence performed 5 minutes after the continuous inhalation of 100% O(2) with a resultant increase in the signal intensity of the CSF that leads to a greater conspicuity of cyst walls in relation to the cortex and the extraventricular CSF.

Administration, Inhalation↗
PubMed2004

Magic angle effects in MR neurography.

BACKGROUND AND PURPOSE: Magic angle effects are well recognized in MR imaging of tendons and ligaments, but have received virtually no attention in MR neurography. We investigated the hypothesis that signal intensity from peripheral nerves is increased when the nerve's orientation to the constant magnetic induction field (B(0)) approaches 55 degrees (the magic angle). METHODS: Ten volunteers were examined with their peripheral nerves at different orientations to B(0) to detect any changes in signal intensity and provide data to estimate T2. Two patients with rheumatoid arthritis also had their median nerves examined at 0 degrees and 55 degrees. RESULTS: When examined with a short TI inversion-recovery sequence with different TEs, the median nerve showed a 46-175% increase in signal intensity between 0 degrees and 55 degrees and an increase in mean T2 from 47.2 to 65.8 msec. When examined in 5 degrees to 10 degrees increments from 0 degrees to 90 degrees, the median nerve signal intensity changed in a manner consistent with the magic angle effect. No significant change was observed in skeletal muscle. Ulnar and sciatic nerves also showed changes in signal intensity depending on their orientation to B(0). Components of the brachial plexus were orientated at about 55 degrees to B(0) and showed a higher signal intensity than that of nerves in the upper arm that were nearly parallel to B(0). A reduction in the change in signal intensity in the median nerve with orientation was observed in the two patients with rheumatoid arthritis. CONCLUSION: Signal intensity of peripheral nerves changes with orientation to B(0). This is probably the result of the magic angle effect from the highly ordered, linearly orientated collagen within them. Differences in signal intensity with orientation may simulate disease and be a source of diagnostic confusion.

Adult↗
PubMed1992

[Studies of the correlations between morphological brain changes on MRI and computerized EEG changes in schizophrenics].

Several researchers have investigated the relationships between computed tomographic and electroencephalographic abnormalities in schizophrenics. In this present investigation, 28 medicated schizophrenic patients fulfilling the DSM-III-R criteria for schizophrenia and 21 normal volunteers were studied by means of MRI and EEG examinations. All subjects had given informed consent to the investigation. The schizophrenic patients (14 males, 14 females) were aged from 21 to 39 with a mean age of 30.2. The control group consisted of age- and sex-matched healthy volunteers (11 males, 11 females) with no history of neurological disease or head trauma. All the subjects were right-handed as determined by the Edinburgh Inventory. Schizophrenic and control subjects underwent MRI scan and EEG within two weeks. Three trained psychiatrists evaluated patients for BPRS and SANS and the score each item was the median of the three raters. MRI scans were performed by a Asahi Super 200 scanner operating at a 2.0 Tesla magnetic field. A midsagittal scan (8 mm thickness, Spin Echo 500/26) was taken. Subsequently, 15 axial and coronal slices of 5 mm interslice with 2 mm gap were obtained using an Inversion-Recovery sequence (TR: 3000, TI: 800, TE: 14). For measurement purposes, the three MRI scans (Fig-1) were recorded on transparent film, and the boundaries of the cerebral structures were taken traced from the film onto a digitizing tablet. The EEGs were recorded from 16 scalp electrodes of the standard 10/20 system referenced to linked ear electrodes at rest and digitized by a topographic system (Neuromap system MCE-5100, QCE-510B, Nihon Kohden). To calculate EEG power, the frequency spectrum was divided into six EEG frequency bands by 0.25 Hz bands. Each power value was taken from the average percentage of total power and then log-transformed. Schizophrenic patients showed a significantly larger VBR on the axial and coronal planes than control subjects. The areas of the bilateral anterior horns, left body, left posterior horn of the lateral ventricle and the third ventricle were significantly larger in schizophrenic patients than in control subjects. The area of middle half of the corpus callosum in schizophrenic patients was smaller than in control subjects. Schizophrenic patients showed more delta and theta activities in the centro-parieto-occipital regions than control subjects. Schizophrenic patients also showed more beta 1 and beta 2 activities in front-central regions than control subjects. On the other hand, schizophrenic patients showed a markedly decrease in alpha 2 activity in all regions.(ABSTRACT TRUNCATED AT 400 WORDS)

Adult↗