Magnetic resonance of the rheumatoid hand

The purpose of this study was to evaluate MRI diagnostic accuracy in rheumatoid arthritis (RA), to compare MRI and radiological findings and to correlate these findings with the clinical and serological profile of the disease. The hands of 24 patients (20 females, 4 males) affected with typical RA (ARA criteria) were studied using a tomograph Magnetom 1.0 T Siemens. Two patients affected with RA refractory to conventional second-line drugs who received a bolus of methylprednisolone (1 g) were studied before and after such treatment. The hands of healthy volunteers were examined as controls. Besides MRI study all patients underwent: (1) radiological examination of the hands performed with a standard technique and (2) clinical and serological investigation aimed at characterizing diseases activity and extent. The radiographic and MRI findings were evaluated by two different observers who found 15 pathological elementary lesions and assigned a MRI and a radiological score to each patient. MRI exhibited significantly higher accuracy than radiography in evaluating rheumatoid soft-tissue changes and in detecting minimal skeletal lesions, while severe skeletal lesions were better detected by radiology. No correlation was found between pathological MRI findings, radiological results and clinical or serological data. A significant drop in soft-tissue effusion was observed after methylprednisolone pulse in two patients. This study confirms MRI potential in the study of rheumatoid joint lesions and in the early detection of minimal soft-tissue changes. Its use appears to be suitable for accurate monitoring of RA patients under specific therapy.     

Radiographic study of severe Influenza-A (H1N1) disease in children

Objective

To characterize the radiographic findings of pediatric patients with severe Influenza-A (H1N1) disease.

Methods

A retrospective study of data from chest X-ray, CT and MRI exam of 29 pediatric patients treated in intensive care unit for severe Influenza-A (H1N1) disease.

Results

Disease developed quickly at early stage. Here are four types of radiographic findings. The disease continued to progress for 2-3 days and X-ray showed that all 29 patients had increased solid lesions with the existence of interstitial lesions. Four days later, all lung lesions showed absorption to certain degree. Fifteen days later, X-ray and CT showed complete or significant absorption in 19 cases (85.5%); delayed recovery was identified in 8 cases (27.6%), pulmonary fibrosis was found in 3 cases (10.3%), and 3 patients (10.3%) died. But the latter identified more lesions. Cranial CT and MRI were performed for 8 patients who had neurological symptoms. Of them, 3 cases (10.3%) were abnormal, showed symmetrical long T1 and T2 signal shadow in bilateral thalamus and longer T1 and T2 signals in the between. 3 cases had autopsy completed.

Conclusion

The severe Influenza-A (H1N1) among children progression was generally rapid in the first 3 days. The overall radiographic findings are similar to acute respiratory distress syndrome (ARDS). A small portion of the patients occurred acute necrotizing encephalopathy and plastic bronchitis.     

Progressive multifocal leukoencephalopathy.

The radionuclide, radiographic and pathologic findings in a patient with progressive multifocal leukoencephalopathy were correlated. Radionuclide imaging demonstrated the largest two of the many lesions observed at pathology. On repeated studies, one of the lesions developed a "doughnut" sign due to central necrosis. Cerebral angiography disclosed only one lesion which was initially suggestive of tumor encasement, but four weeks later, this deteriorated into an avascular zone. There were no characteristic features of the lesions demonstrated by radionuclide imaging and cerebral angiography that could be specifically attributed to progressive multifocal leukoencephalopathy.     

Juxta-articular erosions in reflex sympathetic dystrophy

Thirty-one patients with documented reflex sympathetic dystrophy syndrome (RSDS) were reviewed for their radiographic changes. Juxta-articular and metaphyseal bone loss was found in the majority of the patients. Juxta-articular bone loss closely resembling erosions seen in rheumatoid arthritis was found in all the patients. The significance of these findings is discussed.     

Relative roles of radionuclide scanning and radiographic imaging in eosinophilic granuloma

Twenty-four skeletal lesions were studied in seven patients with eosinophilic granuloma by radiographic skeletal surveys and radionuclide bone imaging. The radiographs detected 22 (92%) of these lesions and missed only two, whereas the scintiscans identified only 16 (67%) of these lesions, and missed eight. Radiographic skeletal survey and radionuclide bone imaging are complementary procedures in detecting bone lesions in bone marrow disorders, including eosinophilic granuloma. Use of either method alone is fraught with the danger of missing bone lesions of eosinophilic granuloma.     

The pitfalls of planar three-phase bone scintigraphy in nontraumatic hip avascular osteonecrosis.

PURPOSE: This study documented the previously reported lower sensitivity of routine planar three-phase bone scintigraphy (BS) performed using a high-resolution parallel-hole collimator compared with MRI to diagnose nontraumatic avascular necrosis of the hip (AVN). METHODS: Six observers reviewed 143 bone scintigrams obtained in patients with nontraumatic hip pain (n = 120) or a control group (n = 23). All patients had a standard radiograph and MRI within 2 months of the BS. Of 280 hips, 148 (53%) were painful on the day of the examination. The osteonecrosis group (AVN) consisted of 93 instances of AVN in 58 patients. Although it departs from the clinical situation, this method evaluated the intrinsic performance of the imaging method. The data were analyzed using a receiver operating characteristic method. RESULTS: For the six observers, the A(z) values were 0.65, 0.67, 0.66, 0.67, 0.73, and 0.79, respectively, and 0.66, 0.71, 0.75, 0.81, 0.81, 0.82, and 0.84 after removing hip diseases other than AVN through data manipulation. Bone marrow edema, as seen on MRI, was the most frequently reported misleading sign in false-positive diagnoses, especially in the early or late phases of the disease. False-negative diagnoses misclassified the scans as "asymptomatic hips" in 28 of 30 cases. Twenty-two of 30 scans appeared normal, but these AVN lesions were small (<25%) and were discovered by chance on MRIs that displayed bilateral involvement associated with radiographic evidence (stage 0 or 1). Thirteen of 20 patients were followed for 3 or more years, and only one worsened. CONCLUSIONS: BS is not indicated to diagnose possible contralateral AVN if the hip is asymptomatic. This study emphasizes the results from the literature; if indicated, a radionuclide hip investigation requires the use of a pin-hole collimator, a SPECT study with scatter correction and iterative reconstruction algorithms, or both.     

Do MRI features at baseline predict radiographic joint space narrowing in the medial compartment of the osteoarthritic knee 2 years later?

PURPOSE: The purpose of the study was to relate magnetic resonance imaging (MRI) features at baseline with radiographically determined joint space narrowing (JSN) in the medial compartment of the knee after 2 years in a group of patients with symptomatic osteoarthritis at multiple joint sites. MATERIALS AND METHODS: MRI of the knee and standardized radiographs were obtained at baseline and after 2 years in 186 patients (81% female; aged 43-76 years; mean 60 years). MRI was analyzed for bone marrow lesions, cysts, osteophytes, hyaline cartilage defects, joint effusion, and meniscal pathology in the medial compartment. Radiographs were scored semiquantitatively for JSN in the medial tibiofemoral joint using the Osteoarthritis Research Society International (OARSI) atlas. Radiological progression was defined as >/=1 grade increase. Associations between baseline magnetic resonance (MR) parameters and subsequent radiographic JSN changes were assessed using logistic regression. Relative risk (RR) was then calculated. RESULTS: Radiographic progression of JSN was observed in 17 (9.1%) of 186 patients. Eleven patients had a Kellgren and Lawrence (KL) score of >/=2. A significant association was observed between all patients and meniscal tears (RR 3.57; confidence interval (CI) 1.08-10.0) and meniscal subluxation (RR 2.73; CI 1.20-5.41), between KL < 2 and meniscal subluxation (RR 11.3; CI 2.49-29.49) and KL >/= 2 and meniscus tears (RR 8.91; CI 1.13-22.84) and radiographic JSN 2 years later. Follow-up MR in 15 of 17 patients with progressive JSN showed only new meniscal abnormalities and no progression of cartilage loss. CONCLUSION: Meniscal pathology (tears and/or meniscal subluxation) was the only MRI parameter to be associated with subsequent radiographic progression of JSN in the medial tibiofemoral compartment on a radiograph 2 years later, as assessed by the OARSI score.     

Posterior fossa intra-axial tumors: a comparison of computed tomography with other imaging methods.

Fifty patients with posterior fossa intra-axial tumors were evaluated by computed tomography and the results compared with routine skull films, radionuclide brain scanning vertebral angiography, and cerebral air studies. The routine skull series was found to be of little benefit. Computed tomography was more sensitive than the radionuclide brain scan in detecting all of the lesions except astrocytoma, for which sensitivity was comparable. Angiography was the most sensitive means of detecting hemangioblastoma, and was the only reliable radiographic method of differentiating hemangioblastoma from astrocytoma. Cerebral air studies were the most sensitive and specific means of evaluating brainstem gliomas.     

Comparison of whole-body STIR-MRI and <Superscript>99m</Superscript>Tc-methylene-diphosphonate scintigraphy in children with suspected multifocal bone lesions

The study was performed to compare whole-body short time inversion recovery (STIR) MR imaging and ^99mTc-methylene diphosphonate planar scintigraphy in the examination of children with suspected multifocal skeletal malignant lesions. Sixteen patients with known or suspected malignant skeletal disease underwent both whole-body STIR MR imaging and bone scintigraphy. The lesions were described and numbered according to scintigraphic evaluation criteria. Thus, 16 regions were analyzed in each patient for the comparison between the two modalities. Histology was proven in the primary malignant regions. Follow-up MRIs were registered. Scintigraphy and MRI follow-up were evaluated as gold standard. A total of 139 different lesions was observed by both modalities. Baseline whole-body MRI revealed 119 bone lesions in 256 possible sites (46.5%); scintigraphy revealed only 58 lesions (22.6%). Congruence was observed in only four patients (25%). According to the location of the lesion, correlation was observed in 39/139 lesions (28%). In all, 57.5% of the lesions were detected only by MRI and 14.5% of the lesions were detected only by scintigraphy. Whole-body MRI was more sensitive (P<0.001). Of all lesions numbered which could be separated in the initial MRI, whole-body MRI detected 178 lesions in the patients. The results suggest that whole-body MRI using a STIR sequence is an effective radiation free method for examination of children with suspected multifocal bone lesions. MRI showed more lesions than conventional ^99mTc-methylene diphosphonate scintigraphy. Therefore, whole-body MRI may be feasible as a screening modality for metastatic and skip lesions in osteosarcoma, PNET, Ewing sarcoma and Langerhans cell histiocytosis in children.     

The multiscan appearance of eosinophilic granuloma.

A case of multifocal eosinophilic granuloma is presented in which a 99mTc-methylene diphosphonate bone scan revealed areas of increased, normal, and decreased uptake of the radionuclide. A radiographic bone survey demonstrated some but not all of the lesions seen on the bone scan; additionally, certain lesions were demonstrated only by the radiographs. A radionuclide bone scan is therefore unreliable as the sole diagnostic procedure for evaluating the distribution of eosinophilic granuloma and should always be complemented with a radiographic bone survey.     

MRI-Guided Intervention for Breast Lesions Using the Freehand Technique in a 3.0-T Closed-Bore MRI Scanner: Feasibility and Initial Results

Objective

To report the feasibility of magnetic resonance imaging (MRI)-guided intervention for diagnosing suspicious breast lesions detectable by MRI only, using the freehand technique with a 3.0-T closed-bore MRI scanner.

Materials and Methods

Five women with 5 consecutive MRI-only breast lesions underwent MRI-guided intervention: 3 underwent MRI-guided needle localization and 2, MRI-guided vacuum-assisted biopsy. The interventions were performed in a 3.0-T closed-bore MRI system using a dedicated phased-array breast coil with the patients in the prone position; the freehand technique was used. Technical success and histopathologic outcome were analyzed.

Results

MRI showed that four lesions were masses (mean size, 11.5 mm; range, 7-18 mm); and 1, a nonmass-like enhancement (maximum diameter, 21 mm). The locations of the lesions with respect to the breast with index cancer were as follows: different quadrant, same breast - 3 cases; same quadrant, same breast - 1 case; and contralateral breast - 1 case. Histopathologic evaluation of the lesions treated with needle localization disclosed perilobular hemangioma, fibrocystic change, and fibroadenomatous change. The lesions treated with vacuum-assisted biopsy demonstrated a radial scar and atypical apocrine hyperplasia. Follow-up MRI after 2-7 months (mean, 4.6 months) confirmed complete lesion removal in all cases.

Conclusion

MRI-guided intervention for breast lesions using the freehand technique with a 3.0-T closed-bore MRI scanner is feasible and accurate for diagnosing MRI-only lesions.     

Indeterminate or suspicious breast lesions detected initially with MR imaging: value of MRI-directed breast ultrasound

RATIONALE AND OBJECTIVES: To retrospectively determine the value of magnetic resonance imaging (MRI)-directed breast ultrasonography (US) in the evaluation of indeterminate or suspicious lesions identified on contrast-enhanced, breast MRI. MATERIALS AND METHODS: A total of 395 patients presenting for breast MRI during a 4-year period was retrospectively reviewed. Seventy-one patients were recommended for MRI-directed US for further characterization of indeterminate or suspicious breast lesions detected on MRI. Fifty-five patients (all female; age 31-80 years) had US. Their MRI and US were reviewed and tested for correlations with histologic results or long term follow-up. Logistic regression analyses were used to test for associations between MRI lesion characteristics and US detection rate. RESULTS: US identified 46 of 97 (47%) lesions depicted at MRI from 55 patients (47 [85%] of these patients had histories of breast malignancies). Twelve cancers were found from the 97 lesions (12%). Biopsy was avoidable in 10 lesions (10%). The detection rate with US was slightly higher with "mass" (55% [23/42]) lesions described in MRI than "non-mass" lesions or lymph nodes (42% [23/55]). There was a significant positive association (odd ratio = 1.23: 95% CI = 1.05-1.43, P = .01) between US detection rate and MRI mass lesion size. There was no statistical significance between US detection rate and the presence of malignancies; 42% (5/12) of MRI malignant lesions were not visualized with US. CONCLUSIONS: MRI-directed US reduced the number of biopsies required for indeterminate or suspicious MRI lesions. Nevertheless, the lesions which were biopsied had a low rate of malignancy.     

骨的纤维结构不良的X线与MRI表现对比

目的探讨骨的纤维结构不良的X线分型及其相应的MRI表现：方法回顾性分析18例经手术病理证实的骨的纤维结构不良的X线和MRI表现,MRI均做平扫和增强。结果全部病例均为长管状骨,单骨型17例：股骨10例,肱骨5例,桡骨2例;多骨型1例,同时侵犯股骨和胫骨。X线表现分型：磨玻璃型10例,囊肿型6例,丝瓜络型2例;相应MR表现——磨玻璃型：T1WI呈均匀或不均匀等低信号,T2WI呈均匀或不均匀等高信号;囊肿型：T1WI呈均匀极低信号,T2WI为均匀或欠均匀高信号;丝瓜络型：T1WI呈不均匀低信号,T2WI呈不均匀高信号。全部病灶边界清楚,周围可见完整或不完整硬化带,未见明显软组织肿块及骨膜反应,增强后均表现为不同程度均匀或不均匀强化,囊变区边缘强化。结论X线平片仍是诊断骨纤维异常增殖症的良好首选方法,MRI对判断病灶组织变化有帮助,后者是前者有益的补充。     

Three-phase radionuclide bone imaging and magnetic resonance imaging detection of occult knee fractures in athletes

Twelve athletes presenting acute knee injury with normal radiological findings underwent both three-phase radionuclide bone imaging (TPBI) and magnetic resonance imaging (MRI). The association of these highly sensitive diagnostic procedures detected occult fractures in all patients. The areas of signal intensity alterations on MRI corresponded to those of increased radionuclide uptake in blood pool images. However, the same areas seemed to be more extended on delayed TPB images. TPBI yielded early diagnostic information about lesion sites and functional activities, while MRI provided better anatomical definition and specific information about associated soft tissue lesions and served to establish the correct therapeutic approach and follow-up. Correspondence to: I. Baschieri     

Cortical cerebral blood flow in HIV-1-related dementia complex

Dementia complex is a syndrome that affects a high percentage of AIDS patients. Neuroradiological findings may be non-specific and the diagnosis can be difficult in its earlier stages. Preliminary radionuclide studies have recently reported derangements of regional cerebral blood flow (CBF) which may be present before overt anatomical injury. This study reports on cortical and cerebellar CBF changes in 26 patients studied with 99Tcm-HM-PAO and single photon emission computed tomography (SPECT). Extensive cortical CBF derangements were observed in all patients and an evident cerebellar hypoperfusion was also present in three. The prevalence of hypoperfusion was highest in the frontal and parietal lobes. The extension of the hypoperfusion showed a highly significant correlation with the severity of the dementia complex (P less than 0.01 by chi 2 test). The SPECT also showed hypoperfused areas in three patients with normal CT scans and in two patients with normal MRI scans. These results confirm previous preliminary reports on the high prevalence of cortical hypoperfusion in dementia complex and suggest the use of this radionuclide technique to assist in the early diagnosis and follow-up of AIDS patients, especially when CT and MRI are still normal.     

MRI in the diagnosis and treatment of suspected malignant spinal cord compression

It remains unclear whether MRI is essential in all patients with suspected malignant spinal cord compression (MSCC), or whether some patients can be treated on the basis of plain radiographic findings and neurological examination. A prospective study was carried out of 280 consecutive patients with suspected MSCC, and the results of neurological examination plus plain radiographs were compared with MRI. 201 patients had MSCC (186 extradural, 5 intradural extramedullary and 10 intramedullary) and 11 patients had thecal sac compression without evidence of spinal cord compression. 25% of patients with MSCC had two or more levels of compression, 69% of these involving more than one region of the spine. A paraspinal mass was noted at the site of extradural spinal cord compression in 28%, and only one-third of these were detected on plain radiography. Focal radiographic changes and consistent neurology were present in 91 (33%) patients who had not had previous radiotherapy. MRI confirmed the presence of MSCC in 89/91 patients (specificity and positive predictive value of radiographic/clinical findings 98%) and the level of disease in all. MRI led to a change in the radiotherapy plan in 53% of patients (21% major change). The sensory level when present was four or more segments below the MRI level in 25/121 (21%) patients, and two or more levels above in 8/121 (7%) patients. Although focal radiographic abnormalities with consistent neurological findings, when present, accurately predicted the presence and level of MSCC, whole spine MRI is indicated in most patients with suspected MSCC because the additional information may alter the management plan. Treatment may be appropriately initiated on the basis of focal radiographic changes and consistent neurology if MRI is contraindicated or delayed, and in patients with a poor prognosis. In patients in whom there are no focal radiographic abnormalities and consistent neurological findings, urgent MRI is mandatory before radiotherapy is commenced.     

Comparing computerized tomography and magnetic resonance in the study of articular pathology of the knee

The authors present a comparison between the diagnostic accuracy of computed tomography (CT) and magnetic resonance imaging (MRI) in the articular pathologies of the knee. CT and MRI were performed in 30 patients who subsequently underwent surgery. CT and MRI results were compared on three bases: technique, definition of normal anatomy, and diagnostic accuracy. CT allowed a standardization of the technique, while MRI was superior in defining normal anatomy--especially in the study of capsulo-ligamentous structures. In all cases the use of both CT and MRI allowed a correct diagnosis, showing the site, extent and gravity of the lesion. CT proved to be superior to MRI in 4 cases, while MRI corrected CT diagnosis in 11 cases; in 15 patients both techniques had the same diagnostic accuracy. Meniscal tears were better identified by CT, while MRI was superior in the detection of ligamentous lesions and in the characterization of PVNS and tendinitis of the patellar tendon. In conclusion, MRI should be performed in selected cases only, or when CT cannot be trusted; on the other hand, it might also be used as a first-choice diagnostic procedure for synovial pathologies and acute lesions of the anterior cruciate ligament.     

Liver lesion detection,characterization, and effect on patient management: Comparison of single-phase spiral CT and current MR techniques

This study compares liver lesion detection, characterization, and effect on patient management between single-phase spiral CT and MRI using spoiled gradient echo (SGE), T2-weighted fat-suppressed spin echo, and serial post gadolinium SGE. All patients with suspected liver lesions who underwent spiral CT and MRI within a 1-month period between January 1993 and September 1996 were included in the study. Spiral CT and MRI were interpreted prospectively in a blinded fashion by separate individual experienced investigators, and lesion detection and characterization were determined. Confirmation was obtained by surgery (6 patients), biopsy (18 patients), imaging follow-up (36 patients), or combined reading of all imaging studies and clinical follow-up (29 patients). Effect on patient management was determined by combined chart review and interview of the patients' physicians and by retrospective clinical assessment performed by a surgical oncologist and medical oncologist separately. Eighty-nine patients were included in the study. Regarding true positive lesion detection, 295 and 519 lesions were detected on spiral CT and MR images, respectively, which was significantly different on a patient-by-patient basis (P < .001). More lesions were detected on MR than on spiral CT in 44 of 89 patients (49.4%), and 11 of these 44 patients had lesions shown on MRI in whom no lesions were apparent on CT images. No patients had true positive lesions shown on spiral CT that were not shown on MRI. Regarding lesion characterization, 129 and 466 lesions were characterized on spiral CT and MRI images, respectively, which was significantly different on a patient-by-patient basis (P < .001). More lesions were characterized on MR than CT images in 67 patients (75.3%). Regarding effect on patient management, chart review with physician interview demonstrated that findings on MRI provided information that altered patient management as compared with findings on spiral CT in 57 patients. Retrospective clinical evaluation by the surgical and medical oncologist showed that MRI was considered to have a greater effect on patient management than spiral CT in 58 and 55 patients, respectively. Comparing current MRI technique to single-phase spiral CT, MRI detected more lesions in 49.4% and characterized more lesions in 75.3% of patients investigated for focal liver disease. MRI had a greater effect on patient management in each of the three methods than singlephase spiral CT in more than 61% of patients.     

Small (<or= 2 cm) hepatic lesions in colorectal cancer patients: detection and characterization on mangafodipir trisodium-enhanced MRI

OBJECTIVE: The purpose of this study was to evaluate whether mangafodipir trisodium (MnDPDP)-enhanced MRI improves the detection and characterization of small ( 2.0 cm). The differences between MnDPDP-enhanced MRI and helical CT with regard to the detection rates for hepatic lesions and metastases and with regard to the false-positive rates for hepatic metastases were analyzed using the McNemar test. The performances of MnDPDP-enhanced MRI and helical CT in indicating metastases of focal liver lesions were analyzed using receiver operating characteristic curves. RESULTS: No statistically significant differences were seen between MnDPDP-enhanced MRI and helical CT in the detection of all hepatic lesions (p = 0.383) and small lesions (p = 0.210). However, concerning the differentiation between benign and metastatic lesions, MnDPDP-enhanced MRI was superior to helical CT both for all hepatic lesions (p = 0.023) and for small lesions (p = 0.015), and remained better when the analyses were restricted to patients with histopathologic confirmation (p = 0.023 for both). MnDPDP-enhanced MRI changed the diagnosis of hepatic metastasis in nine (13.0%) of 69 patients. Of 12 metastases that were found on MnDPDP-enhanced MRI and missed on helical CT, 11 lesions (91.7%) were small. MnDPDP-enhanced MRI showed a significantly greater detection rate than helical CT for small hepatic metastases (p = 0.022). MnDPDP-enhanced MRI was better when the analyses were restricted to patients with histopathologic confirmation (p = 0.043). CONCLUSION: Although MnDPDP-enhanced MRI is equal to helical CT in detection of both all hepatic lesions and small lesions in patients with colorectal carcinoma, it is superior to CT in characterization of the lesions.     

MRI and CT evaluation of primary bone and soft-tissue tumors

Twenty-six patients with primary tumors of bone or somatic soft tissues underwent both magnetic resonance imaging (MRI) and computed tomography (CT); 15 of the patients had radionuclide bone scans as well. Only in a minority of cases did these tomographic methods provide information needed for diagnosis that could not be derived from the plain radiographs alone; however, for assessing the extent of the disease, both CT and MRI proved very valuable, particularly MRI. Specifically, MRI was superior to CT in delineating the extent of the neoplasms and their relation to surrounding structures in 21 of the patients, equal in four, and inferior in only one. Furthermore, in the 13 patients with tumors of long bone, MRI was judged superior to CT in visualizing marrow abnormality in 12 cases, and equal in only one case. Radionuclide scans demonstrated the lesions in 14 of the 15 cases; its primary utility was in excluding additional lesions. It is concluded that for these patients, MRI was the imaging method of choice in assessing the extent of bone and soft-tissue tumors.