The effect of contrast media on the synovial membrane

OBJECTIVE

To examine the effect of intra-articular injection of contrast media, sorbitol and normal saline on the synovial membrane.

MATERIALS AND METHODS

Sixty three rabbits (126 knees) were used in this study. We injected the knees with amidotrizoate, ioxaglate, iopamidol, iotrol and diluted gadolinium-DTPA (2 mmol/l). Normal saline and sorbitol 27.25% were used for comparison. A histological and histochemical examination of the knees was carried out 1, 2, 10, 20, 30, 40 and 60 days after the injection.

RESULTS

On histological examination, the knees injected with normal saline, ioxaglate and gadolinium-DTPA had a normal appearance. Intra-articular injection of amidotrizoate, iopamidol, iotrol and sorbitol caused early, mild and transient histological changes of the synovium (synovial hyperplasia, infiltration by leucocytes). Furthermore, the knees injected with amidotrizoate presented with late, extensive histological changes (severe synovial hyperplasia, moderate vascular dilatation, severe infiltration by leukocytes).

CONCLUSION

The results suggest that the chemical structure and not the osmolality of the contrast media is the main cause for the histological changes of the synovium.

[Cervical vascular penetrating trauma]

The case of a 25 year old male with a stab wound of common carotid artery and the internal jugular vein is reported. He was admitted in severe hemorrhagic shock and immediately treated successfully by arterial reconstruction by means of a venous patch. Mild, declining neurological deficits correlated in magnetic resonance imaging with disturbances in the perfusion area of the medial cerebral artery. A survey of the literature shows that the fast repair of the carotid artery is clearly to be given preference to ligature. First can be executed successfully in exceptional emergency cases also by non-carotid surgeons, if basic vascular-surgical techniques are controlled.

Magnetic resonance imaging (MRI) for detection of active sacroiliitis--a prospective study comparing conventional radiography, scintigraphy, and contrast enhanced MRI

OBJECTIVE

Sacroiliitis is often difficult to diagnose in the absence of radiographic alterations. For the diagnosis of active sacroiliitis, plain radiography, scintigraphy, and contrast enhanced magnetic resonance imaging (MRI) were evaluated in a prospective study.

METHODS

In 44 consecutive patients with complete clinical and laboratory evaluation, plain radiographs, quantitative sacroiliac (SI) scintigraphy, and MRI were performed to evaluate the contribution of these imaging techniques to the diagnosis of active sacroiliitis. Scintiscanning and MRI were done in 20 control subjects to define the normal range of imaging findings. We determined the sensitivity and specificity for each imaging method using a reference standard based on clinical symptoms of inflammatory low back pain with or without laboratory signs, and on clinical and radiographic followup during 1.5-2.5 years to confirm diagnosis.

RESULTS

MRI was most sensitive (95%) and superior to quantitative SI scintigraphy (48%) or conventional radiography (19%) for the detection and confirmation of active sacroiliitis. For the assessment of inflammatory signs, MRI had higher specificity (100%) than scintigraphy (97%) or plain radiography (47%). At repeat MRI after 2-30 months, there was persistent pathologic signal intensity in the subchondral bone area despite clinically successful antiinflammatory drug therapy.

CONCLUSION

For the assessment of active changes in the synovial portion and the subchondral bone marrow, contrast enhanced MRI is superior to quantitative SI scintigraphy or conventional radiography. MRI picks up an additional 75% of early cases not diagnosed by plain radiography. Scintigraphy is only of limited value. Persistent pathologic signal intensity in the subchondral bone marrow seems to be closely associated with previous inflammatory episodes, thus limiting specificity of MRI for active sacroiliitis. Based on our findings we suggest an algorithm for the evaluation of patients with suspected active sacroiliitis.

[Computerized tomography findings score in the differentiation of adrenal tumors in patients with extra-adrenal malignomas]

PURPOSE

In a retrospective study the diagnostic accuracy of computed tomography for the differentiation of benign from malignant adrenal masses in patients with extra-adrenal malignancies was evaluated. For this differentiation a new score system was tested.

PATIENTS AND METHODS

Size, density, structure, and borders of adrenal masses in 60 patients with extra-adrenal tumours were analysed and scored. The single criteria and the total score values were correlated with the final diagnosis achieved either by histology or by follow-up CT examinations.

RESULTS

Score values above 4 indicated always metastases and score values below 2 were benign lesions. An overlap occurred at score values between 2 and 3 resulting in an overall accuracy of 83.3%.

CONCLUSION

Single CT criteria are not reliable enough to differentiate benign from malignant adrenal lesions: better results are achieved by using our scoring system.

HIV-related metabolic abnormalities in the brain: depiction with proton MR spectroscopy with short echo times

PURPOSE

To analyze brain metabolite changes in human immunodeficiency virus (HIV)-positive neurologically asymptomatic patients and patients with acquired immunodeficiency syndrome (AIDS) dementia complex (ADC).

MATERIALS AND METHODS

Twelve ADC patients, 11 HIV-positive asymptomatic patients, and 10 healthy control subjects underwent magnetic resonance (MR) imaging and proton MR spectroscopy with short echo times. Changes in N-acetyl aspartate (NAA), choline (Cho), myoinositol (MI), and creatine (Cr) were presented as ratios with Cr as the reference.

RESULTS

Statistically significant (P < .05) differences were noted. In ADC patients, all with MR findings of brain atrophy and diffuse white matter disease, NA/Cr decreased (white matter, -31.8%; gray matter, -22.3%), MI/Cr increased (white matter, +42.5%; gray matter, +51.8%), and Cho/Cr increased (white matter, +20.6%; gray matter, +51.7%) compared with healthy control subjects. In HIV-positive asymptomatic patients, NA/Cr decreased slightly (white matter, -6.9%; gray matter, -5.1%), MI/Cr increased slightly (white matter, +13.7%; gray matter, +10.7%), and Cho/Cr did not change.

CONCLUSION

ADC has a uniform pathologic metabolic pattern that affects NAA, MI, and Cho. Proton MR spectroscopy with short echo times helps detect early abnormalities in clinically asymptomatic patients.

[Phantom studies of ultrasound equipment for quality improvement in breast diagnosis]

AIM

According to the German guidelines for quality control of ultrasonic equipment, the following conditions are required for breast ultrasound: A transducer frequency between 5-7.5 MHz and a minimum field of view of 5 cm. Satisfactory images must be obtained in a depth between 0.5 and 4 cm with a wide tolerance of the focal zones. This allows the use of poor quality equipment which does not produce satisfactory image quality and it excludes a number of high frequency and high resolution transducers with a field of view below 5 cm. This study with a test phantom was performed to define image quality objectively.

METHOD

Sixteen ultrasound instruments in different price categories were used to perform standardized examinations on a breast phantom model 550 (ATS Laboratories, Bridgeport, USA). Contrast and spatial resolution in different penetration depths were investigated on cyst phantoms from 1-4 mm diameter and wire targets with defined distances between 0.5-3 mm 4 investigations reported the images.

RESULTS

A positive correlation was seen between price category and image quality.

CONCLUSION

This study demonstrates that transducer frequency and image geometry do not allow sufficient quality control. An improvement of ultrasound diagnosis is only possible if equipment guidelines are based on standard examinations with test phantoms.

[Ultrasound and mammography follow-up of findings after breast saving operation and adjuvant irradiation]

AIM

The aim of our controlled retrospective study was to assess the diagnostic value of sonography for detection and characterisation of changes compared to mammography and palpation.

METHOD

In 80 patients sonographic and clinical follow-up examinations were performed every 3 to 6 months, mammography examinations were performed every 6 to 12 months during the first 2 years after breast-preserving therapy (BPT) and irradiation. Extension, echogenicity, and configuration of lesions in sonography, and semiquantitiative description of diffuse or circumscribed changes in mammography were the basis of comparative follow-up observation.

RESULTS

Postoperative seromas and haematomas, initially presenting echo-free or as hypoechoic lesions, showed an increase in echogenicity within 18 months after irradiation. Fat necrosis occurred in 9.5% of patients, lymph cysts developed in 4%, granuloma in 3%, recurrence of neoplasma in 1.6%. The diffuse loss of transparency in mammography that was associated with radiation therapy, showed a peak 6-12 months after irradiation.

CONCLUSION

Sonography and sonographic guided puncture are mandatory tools to characterise circumscribed unclear lesions after breast-conserving therapy and irradiation in specialised centers. We recommend a 6-month interval for combined sonography, palpation, and mammography within the first 2 years after BPT and irradiation, because shorter control intervals did not result in relevant diagnostic advantages.