Variability in muscle adaptation to electrical stimulation.

The aims were to investigate the plasticity of the myosin heavy chain (MHC) phenotype following neuromuscular electrical stimulation (NMES) and to assess the correlation between MHC isoform distribution and muscle fibre conduction velocity (MFCV).14 men were subjected to 24 sessions of quadriceps NMES. Needle biopsies were taken from the dominant vastus lateralis and neuromuscular tests were performed on the dominant thigh before and after training. NMES significantly increased the quadriceps maximal force by 14.4±19.7% (P=0.02), vastus lateralis thickness by 10.7±8.6% (P=0.01), vastus lateralis MFCV by 11.1±3.5% (P<0.001), vastus medialis MFCV by 8.4±1.8% (P<0.001). The whole spectrum of possible MHC isoform adaptations to training was observed: fast-to-slow transition (4 subjects), bi-directional transformation from MHC-1 and MHC-2X isoforms toward MHC-2A isoform (7 subjects), shift toward MHC-2X (2 subjects), no MHC distribution change (1 subject). No significant correlation was observed between MHC-2 relative content and vastus lateralis MFCV (pre-training: R2=0.04, P=0.46; post-training: R2=0.02, P=0.67). NMES elicited distinct adaptations in the MHC composition and increased force, muscle thickness, and MFCV. The MHC isoform distribution did not correlate with MFCV, thus implying that the proportion of different fibre types cannot be estimated from this electrophysiological variable.

The latest in ultrasound: three-dimensional imaging. Part II.

INTRODUCTION: The three-dimensional (3D) reconstruction of ultrasound images has become a widespread option in ultrasound equipment. Specific softwares have become available and 3D reconstruction feasible since the early 1990s, particularly since 1994. POSSIBLE CLINICAL APPLICATIONS: Several clinical applications are feasible in all parenchymatous organs (mainly the liver and prostate), hollow viscera (e.g. the bladder and gallbladder), peripheral vessels (supra-aortic trunks and limb vessels) and central (the aorta and iliac arteries) or cerebral vessels. Moreover, tumoral vessels in parenchymatous organs can be reconstructed, and even the fetus in the uterine cavity, with excellent detailing. The recent introduction of echocontrast agents and second harmonic imaging has permitted to study normal and abnormal peripheral, central and parenchymatous vessels, with similar patterns to those obtained with digital angiography. The spatial relationships between the vascular structures of the liver, kidney and placenta were studied with 3D ultrasound angiograms. The applications of this new technique include the analysis of vascular anatomy and the potential assessment of organ perfusion. THE LATEST APPLICATIONS--INTRAVASCULAR STUDIES: Some catheters with an ultrasound transducer in the tip have been tested for intravascular studies. Just like conventional transducers, they provide two-dimensional (2D) images which are then postprocessed into longitudinal 3D or volume reconstructions. The former resemble angiographic images and can be viewed 3D rotating the image along its longitudinal axis. Volume images, which are more complex and slower to obtain, can be rotated on any spatial plane and provide rich detailing of the internal vascular lumen. The clinical importance of intravascular ultrasound with 3D volume reconstructions lies in the diagnosis of vascular conditions and the assessment and monitoring of intravascular interventional procedures--e.g. to detect inaccurate deployment of intravascular stents and endoluminal grafts during the maneuver. Three-dimensional reconstructions involve geometric data assembly and volumetric interpolation of a spatially related sequence of tomographic cross sections generated by an ultrasound catheter withdrawn at a constant rate through a vascular segment of interest, resulting in the display of a straight segment. Therefore particular care is needed and there are some useful hints to avoid mistakes. CONCLUSIONS: Three dimensional reconstructions of B-mode and color Doppler images are no longer a work in progress and their clinical importance and possible applications are both established and ever-increasing. On the other hand, independent of the different types of energy used, also computed tomography and magnetic resonance 3D reconstructions are very useful from a clinical viewpoint and they have become an established routine technique for both these methods. It is very likely that 3D volume reconstructions in ultrasound will find numerous applications in the near future. They may help to increase the diagnostic confidence and to facilitate diagnosis, intraprocedure monitoring in interventional radiology and follow-up and also to reduce the number of invasive examinations with iodinated contrast agents. This could result in cutting the cost and duration of the most expensive examinations. New, although invasive, applications can be hypothesized for intravascular or intraluminal catheters with an ultrasound transducer inside.

Ultrasound contrast agents: basic principles.

INTRODUCTION: Ultrasonography lacked substances to be administered to patients to improve or increase the diagnostic yield, which is peculiar considering that contrast agents have long been used with all the other imaging techniques. Fortunately some contrast agents, most of them consisting in gas microbubbles, have been recently introduced for ultrasound imaging too: this review will focus on their history, behavior, current applications and future developments. Echocontrast agent research is in progress and many new agents are expected to be marketed this and next year, to be added to Levovist by Schering AG (Berlin, Germany), to enhance the ultrasound signal safely and effectively. No definitive conclusions can be drawn yet on the actual merits of each contrast agent, but all of them seem to be both effective and safe, meaning that their future success will depend on the relative cost-effectiveness and peculiarities. THE BASIC PRINCIPLES OF ECHOCONTRAST AGENTS: The microbubbles act as echo-enhancers by basically the same mechanism as that determining echo-scattering in all the other cases of diagnostic ultrasound, namely that the backscattering echo intensity is proportional to the change in acoustic impedance between the blood and the gas making the bubbles. The different acoustic impedance at this interface is very high and in fact all of the incident sound is reflected, even though not all of it will of course go back to the transducer. But the acoustic wave reflection, though nearly complete, would not be sufficient to determine a strong US enhancement because the microbubbles are very small and are sparse in the circulation. Moreover, reflectivity is proportional to the fourth power of a particle diameter but also directly proportional to the concentration of the particles themselves. SECOND HARMONIC IMAGING: As we said above, the microbubbles reached by an ultrasound signal resonate with a specific frequency depending on microbubble diameter. However, the main resonance frequency is not the only resonance frequency of the bubble itself and multiple frequencies of the fundamental one are emitted, just like in a musical instrument. These harmonic frequencies have decreasing intensity, but the second frequency, known as the second harmonic, is still strong enough to be used for diagnostic purposes. The theoretical advantage of the harmonic over the fundamental frequency is that only contrast agent microbubbles resonate with harmonic frequencies, while adjacent tissues do not resonate, or else their harmonic resonation is very little. Thus, using a unit especially set to produce ultrasounds at a given frequency (3.5 MHz) and receive an ultrasound signal twice as powerful (7 MHz) it will be possible to show the contrast agent only, without any artifact from the surrounding anatomical structures, with a markedly improved signal-to-noise ratio. A similar effect to digital subtraction in angiography can thus be obtained, even though through a totally different process. Moreover, second harmonic imaging permits to show extremely small vessels (down to 40 microm) with very slow flow, which would be missed with a conventional method. B-mode imaging can also depict the microbubbles in the myocardium suppressing nearly all the artifacts from cardiac muscle motion. Recently a peculiar behavior of microbubbles has been observed which may permit contrast agent detection even in capillaries. This method is variously known as sonoscintigraphy, loss of correlation, stimulated acoustic emission and transient scattering. The contrast agent microbubbles reached by an ultrasound beam powerful enough explode producing a strong and very short backscatter echo which is read by the unit as a Doppler signal and results in a color pixel where the individual microbubble exploded. CONCLUSIONS: The microbubble contrast agents developed and introduced as safe and effective echo-enhancers in present-day clinical practice will open up new oppurtunities

Contrast enhancing agents in ultrasonography: clinical applications.

INTRODUCTION: As ultrasound remains a poorly sensitive method, echocontrast agents make a real difference. At least 29 echocontrast agents are currently on trial worldwide; their chemical composition, mechanisms of action and possible clinical applications are different. The state of the art of echocontrast agents is discussed: their established applications, those expected in the near future and finally their hypothetical, ideal applications. POTENTIAL CLINICAL APPLICATIONS: An extravascular and a vascular domain can be considered. The former includes the gastrointestinal tract and body cavities--both the normal (bladder, uterus, tubes and so on) and the abnormal (abscesses, fistulas, pericardium, peritoneum and so on) ones. Echocontrast agents can: (1) create or improve an acoustic window; (2) distend some organs and fill them with a liquid, with homogenous attenuation of the ultrasound beam; (3) displace the air-containing intestinal loops; (4) depict the walls, the shape and the contours of a normal or abnormal cavity; (5) detect abnormal communications, fistulas and drainages; and (6) evaluate the amount of fluid in the pleural, pericardial or peritoneal cavities. As for vascular applications, this domain sees the highest number of echocontrast agents on trial or on the market. The best know of them are: Levovist (Schering AG, Berlin, Germany), BR1 (Bracco, Milan, Italy) and EchoGen (Abbott, USA). All these act by enhancing arteries, veins and capillaries. The clinical applications validated in clinical trials mainly regard studies in intracranial and neck vessels and the vascularity of upper and especially lower limbs of renal vessels. Tumor macrovascularity (and in the future, hopefully microvascularity) can also be studied in parenchymatous and/or glandular organs, as well as in intra- and extra-abdominal parenchymatous organs in the periskeletal soft tissues. Clinical validation has also been obtained in the follow-up of tumors submitted to ablation therapy (chemoembolization, ethanol injection, thermal ablation) and in echocardiography, both for morphological studies in the cardiac cavities and for the cardiac wall perfusion. CONCLUSIONS: In a subgroup of 513 out of 1275 patients examined Europe-wide, the contrast agent Levovist increased the diagnostic confidence from 27.4 +/- 22.5 to 77.2 +/- 22.5%. Such data encourage further trials to validate current preliminary results.

Ultrasound and MRI for the long-term evaluation of surgical repair of the rotator cuffs.

About 1 year after surgery to repair the rotator cuff, a total of 20 patients (80% monotendinous injuries, 20% bitendinous injuries) were submitted to ultrasound and MRI to evaluate repair, quality of residual tissue, and to reveal any discrepancies between the two instrumental tests. The results showed that there was normal tendinous integrity in 16 cases (group A), while there were partial injuries, without evidence of complete lesion, in 4 cases (group B); tendinous thinning was evident in 10 patients (50%), while there were areas of intratendinous degeneration in 40% of the cases. The authors observed agreement between the data obtained by the two methods in 75% of cases, and emphasize the effectiveness of the two methods in postoperative evaluation of the cuff; they also confirm the tendinous dishomogeneousness observed in the patients in group B, not associated with poor clinical results, considering the absence of significant differences in the functional results between the two groups.

Topical role and future perspectives of sonographic contrast agents in the differential diagnosis of solid thyroid lesions.

Gray scale sonography and US-guided biopsy are cost-effective and reliable procedures in the differential diagnosis of focal thyroid lesions. The frequent presence of multiple foci can make multiple biopsies intolerable to the patient. The use of a sonographic contrast agent (Levovist) composed of microbubbles was evaluated in the differential diagnosis of focal solid lesions of the thyroid. Time/intensity curves after bolus injection of contrast were studied with samplings at the level of focal lesions, extranodular parenchyma and common carotid in 29 lesions of 25 patients (16 females and 9 males) ranging in age 21 to 68 years. The evaluated parameters were: the curve morphology, the time to peak value, the mean enhancement time and the wash-in/out variate gamma curve. All focal lesions underwent biopsy. No significant differences were observed as for mean enhancement time while for time to peak values only two malignant lesions seemed to show values different from those of other solid lesions. Wash-in/out variate gamma curves seemed more interesting; they presented a dual morphology: 1) parenchymal for hyperplastic areas, pseudonodular neoformations during thyroiditis and healthy thyroid parenchyma, 2) vascular for malignant lesions and carotid lumen. Autonomous nodules showed an intermediate morphology. In spite of major limitations, the results seem to pave the way for additional possibilities of noninvasive differential diagnosis in the evaluation of focal solid thyroid lesions.

[Bone callus: possible assessment with color Doppler ultrasonography. Normal bone healing process]. / Il callo osseo: possibilità di valutazione mediante eco color Doppler. Processo osteoriparativo normale.

Conventional US demonstrates bone callus dimensions and structure, which permits to monitor the bone healing process. January, 1993, through May, 1995, we examined 108 patients with simple fractures of humerus, femur and tibia; all the fractures had been treated with an external or intramedullary metallic fixator. All the patients were submitted to conventional and color-Doppler US of the fracture focus on all possible scanning planes. We considered morphological parameters (the presence/absence of vessels, their number and shape) and functional parameters (the resistive index and the presence of a telesystolic notch). Color-Doppler US and the spectral analysis allowed us to add functional data, on bone callus and newly formed bone vascularization, to morphological studies. In the patients with positive fracture evolution, the caliber of afferent vessels progressively increased, their number decreased and branches appeared. The RI progressively increased, up to similar values to those of nutrient vessels (.36 to .90). Within the second month of fracture, a telesystolic notch appears: this indicates a muscular tunic in the vessel wall, meaning a mature, and no longer a newly formed, vessel. The normal evolution of bone healing may be interrupted by several mechanical and biohumoral factors which reportedly act in a similar way by reducing the number of vessels and increasing peripheral resistance in residual vessels because of fibrosclerotic involution of bone healing. Color-Doppler US permits noninvasive, repeatable and nearly real-time monitoring of bone fracture healing, which suggests this technique could be used: -to assess the results of treatment changes (e.g., loading, external fixator adjustments); -to study the definitive callus; -for the medicolegal assessment of delayed bone healing and of pseudoarthrosis; -for real-time treatment planning, according to color-Doppler findings, and to monitor treatment results.

[Echography in the study of periskeletal soft tissues: technique, normal and pathologic pictures]. / L'ecografia nello studio dei tessuti molli perischeletrici: tecnica, quadri normali e patologici.

Ultrasonography (US) is the method of choice in the study of normal soft tissue patterns thanks to its intrinsic features. The exam must be performed following strict directions relative to US units (last-generation), to probes (high-frequency, high axial and lateral resolution, focusing), the type of scan (orthogonal and oblique scans), the use of silicon pads. Exam reporting and the exact knowledge of possible image artifacts are of the utmost importance. Normal patterns in the skin, subcutaneous tissue, striate muscles, tendons and bursae, nerves, vessels and bone are reported and correlated with the corresponding US patterns in pathologic conditions. In inflammatory processes, muscles and tendons exhibit blurred, irregular and poorly-defined outlines; neither the anatomical structures nor the tissues nearby are infiltrated. Similar patterns are observed in some benign tumors, while in malignant lesions soft tissue echostructure is more or less alterated and the adjacent tissues are infiltrated. Color-Doppler US yields morphologic and functional information as to pathologic vascularization; typical findings, similar to those obtained by means of angiography, are seen in malignant lesions.

[Rheumatoid arthritis: echographic study of lesions of the periskeletal soft tissues]. / Artrite reumatoide: studio ecografico delle lesioni dei tessuti molli perischeletrici.

The role of US was investigated in the study of rheumatoid arthritis, since the method depicts the changes in the periskeletal soft tissues--i.e., where the disorder preferably locates in both its early and late phases. A hundred and fifty-eight patients affected with rheumatoid arthritis according to American Rheumatism Association criteria were examined: the hand (wrist, carpus, metacarpus and fingers), the knee and the foot (metatarsus and toes) were studied in all patients. The study population was divided into two groups according to the time of onset of the disease: in 82 of them (52%) the onset of symptoms dated back to less than a year, while 76 of them (48%) had been suffering for over a year. US appears as the most accurate method to study the early phases of rheumatoid arthritis, for it makes early diagnosis possible, thus allowing the correct treatment to be chosen and preventing the disease from causing the irreversible lesions which progressively disable the patient. In the early phases of rheumatoid arthritis, US detects the exudative effects of synovial inflammation in periskeletal soft tissues. Joint effusions and synovial pannus are also depicted by US, as well as the thickening of tendon sheaths and tendon ruptures and rheumatoid nodules. In the late phases of rheumatoid arthritis, US supports conventional radiology, the latter remaining the irreplaceable method of choice to demonstrate skeletal lesions. Nonetheless, in such phases US yields further information on periarticular soft tissue involvement which no other method would make available--e.g., the presence of effusions, bulgings, synovial pannus, joint cartilage erosions, damaged tendons and sheaths, hypoplasia of the muscles ending on the involved joint and finally periarticular changes. Finally, US proves of great value in the early demonstration of reactivating phases, with unquestionable prognostic advantages.

[Echographic assessment of the hand: normal anatomy and pathologic patterns]. / Studio ecografico della mano: anatomia normale e quadri patologici.

Ultrasonography (US) can ben used to study the hand thanks to small-parts probes whose frequency ranges 7.5 MHz to 20 MHz. Due to the complex hand anatomy, the clinician often needs further data relative to periskeletal soft tissues and vessels, which are provided by color Doppler US. Our personal series included 465 patients and a group of 20 healthy volunteers. A silicon pad was used to ensure max. adhesion to probe surface, given the uneven surface of the examined structures. Besides normal anatomic patterns, US demonstrated pathologic features in tendons, sheaths and muscles. As for tendons, stenosing and hypertrophic-exudative tenosynovites were depicted, as well as cysts and ruptures. As for muscles, the main findings were ruptures and, rarely, tumors. Relative to joints, arthrogenous ganglia and rheumatism were observed. Finally, the carpal tunnel syndrome was accurately investigated, where US revealed tenovaginalitis with sheath thickening and deformed and compressed median nerve in the carpal tunnel. Also the benign and malignant masses whose primary location is the nervous tissue are easily demonstrated on US, their typical shape being ovalar. To conclude, US proved extremely accurate in all the surgical patients, exhibiting 100% sensitivity in all of them; its specificity ranged from 84% for tendons, to 81% for muscles, 79% for nervous tissues and finally 82% for joint disorders.

[Evaluation of results of leg tendon reconstruction. Ultrasonography features]. / Valutazione dei risultati della ricostruzione dei tendini della gamba. Aspetti ecografici.

INTRODUCTION: The role of ultrasound (US) in the postoperative assessment of tendon reconstruction is not clearly defined and there is no systematic arrangement of US patterns. MATERIAL AND METHODS: We examined 34 patients submitted to surgery or conservative treatment for total/partial tear or musculotendinous detachment of patellar or Achilles tendon in the last 5 years. All patients underwent physical and US examinations. RESULTS: The surgical tendon exhibited the same US patterns in 23/28 patients: it was markedly enlarged (three-/fourfold the normal diameter) and more rounded, with inhomogeneous and hypoechoic appearance not only at the tear/surgical site but also above and below it, for some cm. Small hyperechoic images, mainly dots, were seen in 19 cases, which were referrable to small calcifications and stitches. More and larger calcifications were found in 8 patients, where they were associated with anechoic degeneration areas. Color Doppler US showed moderate or strong hypervascularization around the tear in the first months postinjury. US patterns did not correlate with physical findings, but color Doppler patterns did. In 6 cases of musculotendinous detachment submitted to conservative treatment, US showed enlargement and hypoechogenicity in the injury site only, with no involvement of the remaining tendon. US was also used to time and guide drainage of perilesional hematomas, which were often quite large. CONCLUSIONS: US is the method of choice in the postoperative follow-up of tendon tears and musculotendinous detachments because it shows abnormal signs which are missed at clinics and provides additional information needed for treatment planning.

Selection of patients for carotid endarterectomy: the role of ultrasound.

Stroke is the third leading cause of death in the western world and the major cause of disability among the middle aged and elderly populations. Carotid artery stenosis is the single most important risk factor for stroke. The North American Symptomatic Carotid Endarterectomy Trial and the European Carotid Surgery Trial have demonstrated that the risk of stroke is reduced by surgery in patients with high grade stenosis. Carotid plaque morphology also plays an important role; plaques which are ulcerated and echolucent are associated with a higher risk of stroke. Arteriography has long been regarded as the gold standard diagnostic tool for evaluation of carotid artery disease, but it is an invasive and costly technique which carries the risk of potentially serious complications. Doppler ultrasound can provide functional and anatomical information on vessel stenosis and plaque morphology at sub-millimetric resolutions and is an inexpensive and noninvasive tool. Color and spectral Doppler ultrasound are now recognized as the best screening tests for carotid artery stenosis. The evidence for its use as the sole diagnostic imaging modality prior to carotid endarterectomy is examined. The recent availability of ultrasound contrast agents helps to distinguish between pseudo- and true occlusions, improves ultrasound images and should help to reduce operator variability.

[Role of color coded duplex sonography in the study of thyroid pathology. Personal experience]. / Ruolo della colour coded duplex sonography nello studio della patologia tiroidea. Esperienza personale.

The authors examined 110 patients with suspected pathologic conditions of the thyroid by means of color-coded duplex US. In addition to the information yielded by conventional US, this technique allows organ vascularization to be demonstrated. Five normal patients were considered as a control group: no tissue vascularization was demonstrated in these cases. In 8 patients presenting with carcinoma or recurrences, vascularization was markedly increased both peripheral and central to the nodule. A few doubts are still to be solved as to the diagnostic value of color-coded duplex US in the evaluation of non-carcinomatous nodular pathologic conditions. As a matter of fact, non-functioning avascular adenomas can be demonstrated only in a very low percentage of cases (66%). Color-coded duplex US proved extremely sensitive and specific in depicting malignant neoplasms. Moreover, the use of fine-needle biopsy could be optimized and subsequently reduced. Color-coded duplex US proved to be markedly superior to other methods and techniques in the study of thyroid diseases, especially thyroiditis and multiple pathologic conditions. The simultaneous presence of hypocapture at scintigraphy and peripheral and central vascularization in a single nodule or within multinodular struma at color-Doppler was highly suggestive of malignant thyroid neoplasm. Color-coded duplex US is a low-cost technique, which can be performed on an outpatient basis. Moreover, it is not invasive, nor does it damage the thyroid. That is why its use is almost mandatory in the study of pathologic conditions of the thyroid.

Color Doppler imaging of liver metastases. The value phase-III of a US contrast agent: SH U 508 A (Levovist) Schering.

In a phase-III multicenter clinical trial, the color Doppler vascular patterns were studied of 34 liver metastases in 18 patients before and after the i.v. injection of SH U 508 A (Levovist), with different US units and probes. The patients were selected as having poor color Doppler signals at unenhanced examinations. Lesion size ranged .8 to 9 cm (mean: 3.5 cm). The primary lesion site was the colon in 14 cases, the breast in 8 cases, the lung in 4, the stomach in 4 cases, the ovary in 3 and finally unknown in 4 cases. Each patient received two to four contrast agent injections, with suggested doses and concentrations (10 ml x 300 mg/ml, 8 ml x 400 mgr/ml). No adverse reactions were observed. Thirteen of 34 lesions exhibited no vascular signals at baseline examinations, 10 exhibited some perilesional color spots or small vessel branches, 5 some internal color spots or vessels and 4 small internal and peripheral vessels. After contrast agent infusion, the vascular patterns were better demonstrated in 28/34 lesions and the signal-to-noise ratio was markedly improved, in a concentration-dependent manner, from 40 to 240s. Five lesions remained avascular, 11 exhibited "basket"-like vascular patterns, 10 "internal flow" patterns and finally 10 lesions exhibited both. No major correlation was observed between vascular pattern and lesion size. To conclude, the use of the intravenous contrast agent SH U 508 A (Levovist) appears to be a promising technique to improve the color Doppler demonstration of focal metastatic liver lesions. Nonetheless, further studies on larger series of cases are needed to differentiate the different primary sites of the metastases.

[SPECT with 99m-TC HM PAO in the study of classical hemicrania]. / La SPET con 99mTc-HM PAO nello studio dell'emicrania classica.

Five patients presenting with migraine attacks underwent Electroencephalography (EEC), Computed Tomography (CT) and Single Photon Emission Tomography (SPECT) with 99mTc-HM PAO. EEG and SPECT were subsequently repeated in the intercritical period. We observed that: two patients only showed non-specific abnormalities in EEG; scans were normal in all patients; all subjects exhibited diffuse cortical hypoperfusion. A strong correlation was always found between clinical presentation and hemispheric impairment. One patient exhibited asymmetrical perfusion between cerebellum hemispheres; intercritical SPECT showed homogeneous distribution of the radio-tracer in four patients. In the last one minimal residual hypoperfusion was observed, although less marked than in the acute phase. Therefore SPECT with 99mTc-HM PAO can be reasonably employed as the examination of choice when a migraine attack is clinically suspected, because of its reproducibility and reliability. It can be easily performed in every nuclear medical center supplied with modern tomographic gamma-cameras.

[Ultrasonography in the preoperative staging of carcinoma of the breast]. / L'ecotomografia nella stadiazione preoperatoria del carcinoma mammario.

Data relative to 51 patients operated for breast carcinoma were retrospectively reviewed. All patients had undergone US and mammographic evaluation of max diameter of the neoplastic nodule. The above data were correlated with pathologic measurements of the surgical specimens. US-pathologic correlation coefficient was extremely high (r = 0.94). US proved especially helpful in those cases where mammography had failed to visualize the mass-namely in patients with dense breasts. Nearly all evaluated carcinomas had a typical US pattern: a hypoechoic lesion with irregular outline. US is recommended in evaluating tumor response to nonsurgical conservative treatment.

[The role of echotomography in sports traumatology of the lower extremity]. / Ruolo dell'ecotomografia nella traumatologia da sport dell'arto inferiore.

Sonography, which is commonly used in the evaluation of muscular traumas following exercise, quite often provides the radiologist with normal findings. One hundred and fifty-nine athletes were considered (170 US examinations), and the clinical diagnoses the patients had been referred for were compared with US findings: the pathologic condition was confirmed in 59% of the cases, while the extant 41% had normal findings. The highest percentage of positive findings was observed in the Achilles tendon region (75%), while the figure dropped to 38% in the thigh. In the latter location, muscular ruptures were confirmed in 69% of the cases, versus 17% in case of muscular distraction. As for the Achilles tendon, pathologic conditions both along the axis and in the insertion of the tendon were confirmed in 20% of the cases, but clinical accuracy was improved by US in 47% and 20% of the patients, respectively, and the diagnosis was changed in 10% and 20% of the cases, respectively. Therefore, clinical accuracy was demonstrated to depend on the pathologic condition as well as on the anatomical region involved.

[Clinical applications of color-Doppler: the parathyroid glands]. / Applicazioni cliniche del color-Doppler: le ghiandole paratiroidi.

The high-resolution appearance of enlarged parathyroid glands is well known. Thus, real-time gray-scale US alone fails to provide, in ENT surgery, adequate sensitivity and specificity rates to differentiate between parathyroid glands, hypoechoic thyroid adenomas and other hypoechoic neck masses. Since parathyroid tissue, in both normal and enlarged glands, is hypervascular, color-Doppler US is used as a sort of non-invasive angiography to identify parathyroid glands. The combined use of B-mode and color-Doppler US allows the vascular features of thyroid masses to be satisfactorily demonstrated, with easy differentiation between enlarged parathyroid glands, featuring diffuse internal vascularization, and thyroid adenomas characterized by rounded peripheral vessels and also lymph nodes and cysts exhibiting different vascular patterns. We studied 25 patients with clinical and biochemical signs of hyperparathyroidism (19 primary and 6 secondary) submitted to surgery in the last 20 months. Every patient was scanned with both B-mode and color-Doppler US. At surgery, 19 parathyroid adenomas were found--16 of them correctly identified preoperatively with color-Doppler US and 3 false negatives (retrotracheal glands). Moreover, 1 false positive was observed due to a small Plummer's adenoma misdiagnosed as an intrathyroid parathyroid adenoma: both lesions had the same vascular pattern on US images. Sensitivity was 84.5% and specificity 93.7%. In secondary HPT patients, 23 hyperplastic glands were found at surgery--21 of them correctly identified preoperatively by color-Doppler US, with 2 false negatives. No false positive was found. Sensitivity was 87.5% and specificity 100%. Sensitivity does not differ very much from what reported in literature. Specificity is clearly increased by the use of color-Doppler US. The possible source of error represented by Plummer's adenomas lead us to investigate pulsed Doppler capabilities in differentiating Plummer's adenomas from PT glands, since color-Doppler findings were similar in the two conditions. Peak velocities recorded with both color and pulsed Doppler showed velocity to range 6 to 40 cm/s in parathyroid glands (mean +/- SD: 14.6 +/- 11.7) and 38 to 120 cm/s in thyrotoxic nodules (mean +/- SD: 78.4 +/- 23). The statistical analysis of the results showed a highly significant difference between the two groups of velocities. Peak velocities as recorded in the main, vessels of the parathyroid glands with color and pulsed Doppler were correlated with the activity of the parathyroid glands.(ABSTRACT TRUNCATED AT 400 WORDS)

[Color Doppler in the echographic evaluation of breast nodules]. / Il contributo del Color Doppler nella valutazione ecografica dei noduli mammari.

The authors report on their experience with color Doppler sonography in the diagnosis of solid breast masses. Twenty-two patients were examined; breast masses were studied with B-mode US first, and then with color Doppler US to evaluate eventual tumor vascularization. Color Doppler US demonstrated only one vascular pole in histologically confirmed benign masses. On the contrary, in 92.8% of histologically confirmed malignant masses, color Doppler easily depicted 2 or more groups of nutritional arteries. Color Doppler makes the diagnosis of malignant masses easier, thus allowing, in the author's opinion, a reduction in the number of biopsies of solid breast masses clinically/mammographically detected. The use of color Doppler US is therefore suggested: the technique is noninvasive, fast, and easy and its widespread use would translate into advantages for both the patient and the clinician.

[Diagnostic reliability of ultrasonography in the preoperative staging of the N parameter in head and neck neoplasms]. / Attendibilità diagnostica dell'ecotomografia nella stadiazione preoperatoria del parametro N nelle neoplasie del capo-collo.

The demonstration of metastatic involvement of neck nodes is a crucial step in the staging of patients with head and neck tumors. Diagnostic accuracy, sensitivity, and specificity of US in the detection of lymph node metastases were evaluated in 48 patients with this type of malignancy. The patients subsequently underwent surgical node dissection. Comparison of US, clinical and histological data demonstrated US to have 93.7% diagnostic accuracy, 100% sensitivity, and 84% specificity--the corresponding clinical values being 81%, 79%, and 84%, respectively. Among several US parameters, a substantial role in differentiating metastatic from tumor-free lymph nodes was played by the evaluation of roundness index (RI), and by the demonstration of an intranodal hyperechoic stria: RI value was always higher than 2 in tumor-free nodes and the hyperechoic stria was always absent in metastatic nodes. US approach never failed to demonstrate metastatic nodes while clinics missed them in 6 patients. Thus, US appears the most valuable diagnostic tool for staging head and neck tumors; its diagnostic accuracy can be increased by the combination with US-guided aspiration biopsy.