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R Lagalla

Publications and source records attributed to R Lagalla.

At least 55 records · Page 3Linked to original sources
PubMed1999

[Color Doppler-echo in rheumatoid arthritis with extra-articular location. Preliminary experience].

INTRODUCTION: Chronic inflammation in rheumatoid arthritis usually involves articular synovia and extends to other joint components such as bursae, tendons and sheaths. Conventional US with high frequency transducers is an accurate tool for assessing abnormal changes in evolutive rheumatoid arthritis. We investigated the role of color and power Doppler imaging in staging extra-articular involvement, monitoring local inflammatory changes and drug treatment response. MATERIAL AND METHODS: We used a color Doppler unit with a 5-10 Mhz transducer and automatic power Doppler switch to examine 23 patients with tenosynovitis of the flexor (4/23) and extensor (8/23) tendons of the hand, Achilles (6/23) and posterior tibial (3/23) tendons, and long head of biceps (2/23) in acute rheumatoid arthritis. Only minimal pressure was exerted with the probe on the patients' skin to avoid compression and collapse of blood vessels. Ten normal volunteers were also examined as a control group. RESULTS: In all 23 acute rheumatoid arthritis patients, conventional US showed tendon involvement with intra-articular fluid, thickened tendons with partial tear and markedly hypoechoic thickened sheaths. Color signals were shown in all patients. Mid-caliber vessels were visualized coursing straight from the sheath deep into the tendon. Intra-articular signals were seen in 10/12 patients only. Spectral analysis showed arterial flow, with RI ranging .40-.70. Power Doppler added no important information, but improved vessel depiction relative to color Doppler thanks to its higher accuracy in detecting flow signals. There were no color signals in the tendons of the 10 healthy volunteers in the control group. No color signals were seen in both joints and tendons in 12 patients submitted to medical treatment. CONCLUSION: Color and power Doppler can be a necessary and useful integration to high resolution US for flow mapping in rheumatoid arthritis patients with tendon and extra-articular involvement. These modes depict local circulation changes related to disease stage and treatment response.

Adult↗
PubMed1998

Monitoring treatment response with color and power Doppler.

Color and power Doppler are now widely used to monitor treatment response because of the latest technologic advances and of the increasing use of echo-enhancing agents. The assessment of treatment response is based on the amount of necrosis obtained and changes in local vascularization indicate a successful treatment. To date, clinical experiences have mainly concerned the treatment of hepatocellular carcinomas, hyperfunctioning nodules of the thyroid and parathyroid glands and the neoadjuvant chemotherapy of breast cancer. Aim of this review is to describe the role and potentials of color and power Doppler in this field. Hepatocellular carcinomas are currently treated with surgery or percutaneous ethanol injection and/or chemoembolization. Treatment response can be monitored with color Doppler: after a successful treatment, color signals are no longer detectable on color Doppler images. Conversely, the presence of arterial signals indicates persistent viable tumor. Unfortunately, color Doppler is limited when the hepatocellular carcinoma is hypovascular, small or deep. Echo-enhancing agents may help overcome these limitations, although spiral computed tomography or dynamic magnetic resonance imaging cannot be replaced yet in the definitive assessment of tumor necrosis. Color and power Doppler are well-established tools in the study of functioning thyroid and parathyroid adenomas after percutaneous ethanol injection. Echo-enhancing agents may improve Doppler sensitivity in the detection of residual viable tissue. Other interesting applications of color and power Doppler in this field are secondary hyperparathyroidism and hyperfunctioning thyreopathies (Graves' disease) treated with mercaptoimidazole. The evaluation of systolic flow velocity in the inferior thyroid artery is more reliable than the quantitative analysis of color signals in monitoring treatment response in Graves' disease. In our experience, systolic velocity in the inferior thyroid artery decreased from 150-250 to 60-80 cm/s after medical therapy. Finally, Doppler studies have provided good results in the follow-up of breast cancers after neoadjuvant therapy. In our experience on 18 patients treated with local parenteral repeated administration of antiblastic drugs, sonography showed no more signals within the lesion in 16 patients at the end of therapy. In the remaining two cases with persistent tumor at ultrasound, some color spots were still present and histopathology confirmed residual tumor cells. In conclusion, the results of color and power Doppler are encouraging. Thus, we believe that Doppler will be increasingly used in monitoring treatment response.

Breast Neoplasms↗
PubMed1998

Image quality control in breast ultrasound.

Sonography is well suited for breast studies. Adequate equipment is needed to acquire high quality images because several technical factors influence ultrasound images. Thus, the use of high frequency dynamic scanning probes, the ultrasound beam focusing corrected for the near field, the adjustment of the gain and image contrast may all interfere with ultrasound beam reflection and scattering, determined by the heterogeneity of the gland parenchyma. In the last few years, a line of ultrasound equipment dedicated to this kind of application has been developed with 'small parts' transducers and frequencies ranging 10-13 MHz. These units can improve the evaluation of superficial structures and provide diagnostic results that conventional equipment cannot achieve. The higher the quality, the more a sonographic image corresponds to real anatomy. This capability depends on the different kinds of system resolution. Axial spatial resolution is the capability to resolve discrete structures along the beam axis. Pulse length is inversely proportional to frequency and thus, the higher the transducer frequency, the better the axial resolution. However, the increase in frequency reduces the depth of penetration of the ultrasound beam. The spectrum of frequencies emitted by the crystal has been recently modified in order to obtain a good trade-off between the beam resolution and its penetration. Indeed, the development of the multifrequency technology allowed to improve the near field resolution while retaining a good penetration into the distant field. Furthermore, the use of compound ceramics with a broad bandwidth helps Doppler analysis because flow studies are optimized by low frequencies, whereas two-dimensional morphologic imaging is optimized by high frequencies. Lateral spatial resolution is the capability to resolve discrete structures perpendicular or lateral to the beam axis. This parameter strictly depends on the size of the ultrasound beam section and it is optimal only in the focal area. Therefore, it improves with narrow beams. Several transducers are available in breast sonography, but the most adequate one is currently the annular transducer. The equipment should be able to detect even slight differences in acoustic impedance between the several breast tissues. This may be obtained by optimizing the dynamic range and the pre- and postprocessing setting. Apart from equipment, two other technical factors should be optimized to obtain high quality images, namely beam intensity and gain curve. A new Doppler technique has been recently introduced: power Doppler, which allows the demonstration of breast nodule vascularization with higher sensitivity than color Doppler. Finally, a rigorous examination technique is required to obtain high quality images. In the last few years, several quality assurance programs have been introduced. Dedicated phantoms are generally used. Recently, computer systems have been also developed.

Breast Diseases↗
PubMed1998

Color Doppler ultrasonography of soft-tissue masses.

PURPOSE: To evaluate the capability of color Doppler ultrasonography to differentiate between benign and malignant soft-tissue tumors. MATERIAL AND METHODS: We reviewed the ultrasonographic (US) and color Doppler (CD) findings in 46 consecutive patients with a palpable periskeletal mass. The presence of 3 or more vascular hila and of tortuous and irregular internal vessels within the lesions was considered an indication of malignancy. The CD diagnosis was compared with that obtained at US alone. RESULTS: The sensitivity and specificity of CD were respectively 85% and 92%; these values were higher than those obtained at US alone, respectively 75% and 50%. Arteriovenous malformations presented as lesions with large internal vessels that had low vascular impedance and were easily diagnosed. The wave form patterns within solid tumors were not specific. CONCLUSION: At present, US is commonly employed to confirm the presence of a suspected soft-tissue mass, to locate it accurately, and to indicate its nature. CD finding enhance the role of the US technique in such lesions. The combined use of US and CD can allow the differentiation of benign from malignant lesions, and thus provide a better basis for treatment.

Adolescent↗
PubMed1998

[The heart of the patient with beta thalassemia major. Study with magnetic resonance].

PURPOSE: The main cause of death in beta-thalassemia major patients is congestive heart failure which is traditionally referred to myocardial iron overload. Recently, some investigators have found that cardiac failure is not caused by the iron overload. In their opinion, left-sided heart failure develops years after the onset of acute myocarditis and might be related to a late autoimmune process. Right-sided heart failure is related to the combination of left ventricular diastolic restriction and pulmonary hypertension. The aim of this work is to study myocardial iron overload by MRI and to correlate the signal intensity changes of the myocardium with cardiac function. MATERIAL AND METHODS: Sixteen patients with beta-thalassemia major were examined with a .5 super-conducting unit. SE and cine-GE sequences were used in the 4 chamber and 2 chamber views. Left ventirclar ejection fraction (EF) was calculated by using the biplane area-length method. Right ventricular size was assessed by measuring the end-diastolic anteroposterior diameter (APD). Myocardial signal intensity was evaluated qualitatively and quantitatively (myocardium/subcutaneous fat) in all the beta-thalassemia patients and in 10 normal volunteers. RESULTS: Left ventricular function was decreased (EF < 55%) in 2/16 patients. The right ventricle was dilated in 5/16 patients (APD > 42 mm). The myocardium had a lower signal intensity than that of normal volunteers in 15/16 patients. No statistical correlation was found between myocardial signal intensity and serum ferritine levels or cardiac function. CONCLUSIONS: The small number of patients in our series does not allow any definitive statements. However, our results show that cardiac function is not influenced by myocardial iron overload.

Adolescent↗
PubMed1998

[The assessment of skin tumors with magnetic resonance with high resolution and a paramagnetic contrast medium].

INTRODUCTION: The technologic improvement of surface coils in MRI has allowed better visualization of the skin and thus permitted the clinical use of this technique in dermatology. MRI allows to assess the depth and extent of skin tumors and to detect any malignant transformation. The MR differentiation between benign and malignant skin lesions relies on morphological criteria which however do not have an absolute diagnostic value. We investigated the role of paramagnetic contrast agents in the differentiation between benign and malignant skin lesions. MATERIAL AND METHODS: Forty-one patients, 33 with benign and 8 with malignant skin tumors, were submitted to MRI. All the examinations were performed with a 1.5 T superconductive unit, with a 2.5 cm surface coil. Axial T1- and T2-weighted SE images were acquired with 2 mm slice thickness. Paramagnetic contrast material was administered to all patients. The signal intensity of the skin lesions was calculated before and after paramagnetic contrast agent administration positioning a region of interest. A percentage ratio of contrast enhancement was calculated to quantify contrast agent uptake and the relative values were compared between benign and malignant lesions. A qualitative analysis was also performed rating the contrast enhancement of each lesion as high, intermediate, or absent. RESULTS: The quantitative analysis showed a statistically significant difference (p < .5) between the contrast enhancement values of benign and malignant lesions. In particular, malignancies had values ranging 117.3 (+/- 28.7) to 125 (+/- 32.4), while benign lesions had -20.6 to 99.8 (+/- 21.1). Conversely, no difference in contrast enhancement was found at qualitative analysis. CONCLUSIONS: MRI is a promising tool for characterizing skin tumors. Our preliminary results should be confirmed on larger series of patients with the use of high temporal resolution imaging sequences.

Adolescent↗
PubMed1998

[Magnetic resonance imaging of seronegative sacroiliitis].

INTRODUCTION: The inflammatory involvement of the sacroiliac joint is frequent during seronegative spondylarthritis. The clinical diagnosis of sacroiliitis may be very difficult, especially in the early stage, because joint motion cannot be assessed directly and the clinical picture is very similar to that of lumbar pain. Conventional radiography is negative as long as the structural change in the joint is limited to the synovial membrane and the cartilage (early stage). Computed Tomography (CT) also has many drawbacks, and thus the changes can be shown only when chondritis and enthesitis have already damaged the bone. The disease onset is usually preceded by a long latency; early diagnosis is needed for a proper and timely treatment, which can be made only with a highly sensitive and specific technique. We investigated the diagnostic accuracy of MRI in the early detection of sacroiliitis during seronegative spondylarthritis. MATERIAL AND METHODS: Forty patients with suspected sacroiliitis and negative radiographic findings were submitted to MRI; thirty-seven of them were HLA B27 positive. MRI was performed with a .5 T superconducting unit; T1-weighted SE, T2-weighted FSE, T2* GE, and STIR images were acquired on the oblique coronal plane parallel to the anterior sacrum. Ten asymptomatic volunteers were also examined as a control group. RESULTS: An irregular sacral border and marrow changes at the insertion of the sacroiliac ligaments were seen in 3/10 asymptomatic volunteers. MRI was negative in 7/40 patients, while the synovial compartment was replaced by some tissue with low signal intensity of T1 and high signal on T2 in the other 33 patients; this finding was referred to synovial pannus. Persisting low-signal foci were seen in the synovial compartment in 16/33 patients, which were referred to spared cartilage. High-signal regions were depicted at the bone periphery in 9/33 patients, which areas were consistent with bone erosion; the subchondral bone was markedly hypointense in 5 of these patients, indicating sclerosis. Finally, diffuse high signal intensity was found in the bone marrow in 3/33 patients and referred to infectious sacroiliitis. CONCLUSIONS: MRI appears the method of choice for the early detection of seronegative sacroiliitis because it can show the early changes in cartilage and subchondral bone, filling the gap between the onset of symptoms and radiographic evidence. Moreover, MRI uses no ionizing radiations and makes therefore a precious tool for the diagnosis and follow-up of young patients, hopefully decreasing the use of CT which however provides better detailing of bone and bone degeneration.

Arthritis↗
PubMed1997

Magnetic resonance findings in scuba diving-related spinal cord decompression sickness.

Scuba diving is associated with risk of severe decompression sickness (DCS type II), which results from rapid reduction of the environmental pressure sufficient to cause the formation into tissue or blood of inert gas bubbles previously loaded within tissues as a soluble phase. DCS type II constitutes a unique subset of ischemic insults to the central nervous system (CNS) with primarily involvement of the spinal cord. Ten patients with diving-related barotrauma underwent neurologic examination. Two of them presented progressive sensory and motor loss in the extremities at admission and were presumed affected by spinal cord DCS. Magnetic resonance imaging (MRI) demonstrated abnormalities in the white-matter tracts of the spinal cord in these patients, in each case corresponding to an area of the cord believed to be clinically involved. After a course of therapeutic recompressions, one patient was able to stand and walk a short distance, and MRI revealed a decreased extension of areas of spinal cord abnormalities. MRI has proved to be reliable in the detection of pathologic changes of spinal cord decompression sickness that were previously undetectable by other neuroimaging methods and also has proved to be useful in the follow-up during therapeutic hyperbaric recompressions.

Adolescent↗
PubMed1997

Blood-ocular barrier damage: use of contrast-enhanced MRI.

The blood-ocular barrier (BOB) shares similar neuroepithelial origin, microanatomy and functions with the blood-brain barrier. There are many natural (e. g. diabetes, hypertension) or iatrogenic (chemotherapy, retinal photocoagulation) conditions which can cause a BOB breakdown, resulting in visual acuity impairment or loss. The authors examined 42 patients affected by BOB damage in different pathological conditions. All patients previously underwent a conventional fluoroangiographic (FA) study. Nine patients with normal FA exam were evaluated also. Despite normal MRI findings immediately after Gd-DTPA injection, contrast leakage into the vitreous body or into the aqueous fluid was demonstrated in delayed scans (40-50 min after contrast administration), proving the existence of a BOB damage (sensitively 94 %). Although FA exam remains the choice modality in BOB breakdown demonstration, we propose MRI as a useful diagnostic tool when optic media opacity (cataract, haemovitreous, intraocular silicon oil) occurs, preventing direct retinal fundus imaging and/or an early screening tool.

Adult↗
PubMed1997

Arrhythmogenic right ventricular dysplasia: MR features.

Arrhythmogenic right ventricular dysplasia (ARVD) is a heart disease characterized by a total or partial fat replacement of the myocardium. A total of 30 patients were studied with a suspected diagnosis of ARVD. Clinical criteria used for evaluation of ARVD were: (a) ventricular origin arrhythmias with a left bundle branch block configuration, (b) T-wave inversion in the anterior precordial leads, (c) ventricular kinetic alterations observed using echocardiography and angiography and (d) cardiac failure when there are no pathologies attributable to other heart diseases. All patients had serial EKG and echocardiography tests. One third of patients underwent angiocardiography; 7 of 30 had Holter; 7 of 30 had exercise test just to evaluate the effectiveness of the anti-arrhythmic therapy. All patients underwent MRI examination. The following MRI criteria were used: (a) high-intensity areas indicating the fatty substitution of the myocardium, (b) ectasia of the right ventricular outflow tract, (c) dyskinetic bulges, (d) dilation of the right ventricle and (e) enlargement of the right atrium. The diagnosis of ARVD was classified as highly probable for patients manifesting at least three positive criteria, probable with two positive criteria, dubious with one and negative in the absence of all criteria. Highly probable diagnosis of ARVD was made in 8 patients, probable in 4, dubious in 7 and negative in 11. The MRI technique is very effective in the assessment of ARVD. The MRI criteria may be helpful in the diagnosis of this condition.

Adipose Tissue↗
PubMed1997

Absence of the common crus in Goldenhar syndrome.

We describe an unusual labyrinthine malformation in a case of Goldenhar syndrome studied with CT and steady-state MR imaging. A single posterosuperior semicircular canal was found with no common crus formation. The malformation could not be attributed to any embryologic development. Nosologic considerations are discussed.

Abnormalities, Multiple↗
PubMed1997

[Normal anatomy and pathologic features of the supraspinatus muscle: comparison between ultrasonography and surgery. Analysis of the potential sources of diagnostic errors].

The supraspinatus muscle performs about 60% of the elevation-abduction motion of the arm; therefore, it has a prominent functional role among the extrarotational muscles of the shoulder and is the most injured in subacromial space conditions. Seventy-four patients, aged 21-64 years, were examined to compare ultrasonography (US) results with surgical findings in supraspinatus conditions and to analyze the possible pitfalls in US diagnosis. All the patients underwent conventional X-ray, US and then surgery or arthroscopy. The following criteria were considered: morphology, thickness, echotexture, the convexity of the superior border of supraspinatus tendon, the relationships with the subacromial bursa and the tendon of the biceps long head, the regularity of the bone cortex of the humeral head. US showed: chronic degenerative tendinopathy in 10 patients; perforating focal injuries in 21 patients; deep focal injuries in 10 patients; intramural focal injuries in 6 patients; superficial focal injuries in 8 patients; complete tendon tear with detachment in 19 cases. 62/74 US diagnoses were surgically confirmed, with a specificity of 83.7%. In our experience, US provided very useful information about the pattern, size and site of the injuries and was very helpful in the surgical planning.

Adult↗
PubMed1997

[Biomechanics and semiology of transient lateral patellar dislocation: reliability of magnetic resonance diagnosis].

Transient patellar dislocation is a rare finding. It is usually due to direct trauma in mediolateral direction or to indirect trauma related to violent quadriceps muscle contraction. The clinical diagnosis of transient forms is usually rather difficult because the associated signs (hemarthros and pain at the joint and/or at the vastus medialis insertion) are not specific. Conventional radiography and CT are very accurate in bone studies, but exhibit major limitations in the detection of capsular injuries with intramedullary and/or cartilaginous bone involvement. We investigated MR diagnostic reliability in the study of the injuries caused by transient patellar dislocation. 526 MR examinations of the knee were reviewed retrospectively; fifteen of them were positive for transient patellar dislocation. We used a .5 T superconductive MR unit with a circumferential extremity coil. Axial, coronal and sagittal T1-weighted spin echo, T2*-weighted gradient echo and axial STIR images were acquired. The following criteria were considered specific for the diagnosis of former lateral patellar dislocation: retinacular changes; patella site; signal intensity changes in femoral and patellar intramedullary bone; joint effusion; cartilage and subchondral bone changes. All the patients with transient patellar dislocation had hemarthros with inner retinaculum involvement. The femoropatellar joint was incongruous in 115 cases; patellar subluxation was external in 8/11 patients and lateral in the remaining 3 patients. Medullary bruises were found in 8/15 cases and cartilage injuries in 13/15. Finally, other joint components, such as the posterior horn of the medial meniscus or the anterior cruciate ligament were involved in 6/13 cases. Arthroscopy was performed in 6 patients with associated injuries and confirmed all MR findings (100% agreement). To conclude, in our experience MRI was a very reliable tool to study the injuries due to transient patellar dislocation because it showed specific changes and possible associated traumas, which helps choose the most suitable treatment.

Adolescent↗
PubMed1997

[Potential uses of color Doppler in periskeletal soft tissue neoplasms].

Integrated imaging plays a fundamental role in the study of periskeletal soft tissue tumors, for both diagnosis and treatment planning. The steady and progressive technologic progress of color Doppler US equipment now permits the integration of conventional morphostructural parameters with the biofunctional data of lesion flow patterns and relative qualitative features. To assess color Doppler capabilities in differentiating benign from malignant soft tissue tumors, we reviewed the B-mode and color Doppler findings of 43 consecutive patients with a palpable periskeletal soft tissue mass. All patients were examined with a real time unit (Ultramark 9 HDI), with a broadband (5-10 MHz) linear transducer operating at 6.5 MHz for Doppler measurements. The PRF was set at 1500 to 800 Hz with 70% color gain; a 100 Hz wall filter was used. We kept the color box in the area of interest as small as possible to keep the frame rate high; pulsed Doppler studies were performed with a small sample volume and 2000 Hz PRF. The following signs were considered: morphostructural features; the presence/absence of color signals; the (peripheral/internal) site of vascular branches, their caliber and course; the number of afferent vascular poles; resistance index. As a rule, malignant masses tend to differ from benign masses for the presence of multiple vascular afferent branches, especially if they have an irregular pattern and caliber, and for the variability of the resistance index measured in different parts of the same mass. Further examinations, performed with second level imaging (CT and MRI) and microhistologic tests, respectively after biopsy and surgical resection, confirmed the high predictive value of color Doppler US, with only 1 false negative and 2 false positives; color Doppler sensitivity and specificity were 94.7% and 91.6%, respectively, which are higher values than those obtained with US alone (63% and 66.6%). Therefore, we believe that color Doppler US can be systematically applied to the study of periskeletal soft tissue masses, integrating conventional US for the correct selection of the patients to be submitted to second level investigations.

Adolescent↗
PubMed1996

MRI of the inner ear: use of modified GRASS and fast spin-echo sequences. A preliminary study.

We report our experience with MRI of the normal and pathological inner ear with fast spin-echo and modified gradient recalled at steady state sequences. Although earlier studies on temporal bone MRI were discouraging, improvements in MR technology combined with the use of paramagnetic contrast media can make MRI a useful diagnostic tool for the assessment of inner ear pathology. Conventional spin-echo imaging seems not to be the modality of choice because of the relatively thick slices and the long acquisition times.

Chronic Disease↗