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E Quaia

Publications and source records attributed to E Quaia.

13 recordsLinked to original sources
PubMed2005

Analysis of different contrast enhancement patterns after microbubble-based contrast agent injection in liver hemangiomas with atypical appearance on baseline scan.

BACKGROUND: We describe different possible enhancement patterns in liver hemangiomas with atypical appearance on baseline ultrasound after microbubble-based contrast agent injection. METHODS: From a series of 253 consecutive lesions that were indeterminate on baseline ultrasound and then scanned after injection of air-filled microbubble contrast agent, 65 focal liver lesions were retrospectively selected on the basis of a diagnosis of liver hemangioma on multiphase contrast-enhanced computed tomography (n = 23), magnetic resonance imaging (n = 27), or histology (n = 15). Each lesion was scanned during arterial phase (30 s after microbubble injection) and late phase (5 min after injection). On-site sonologists performed retrospective assessment of contrast-enhancement patterns by consensus. RESULTS: Centripetal fill-in preceded (n = 50) or not preceded (n = 3) by peripheral nodular/rim-like enhancement was the prevalently observed contrast-enhancement pattern, equivalent to the typical enhancement pattern of liver hemangiomas on contrast-enhanced computed tomography or magnetic resonance imaging. In the remaining lesions, additional enhancement patterns (diffuse contrast enhancement with rapid fill-in and a late hyper-isoechoic appearance, n = 6; peripheral nodular enhancement with a late hypoechoic appearance, n = 3; or persistent heterogeneous and hyperechoic appearance, n = 3) were observed. CONCLUSION: Different contrast-enhancement patterns are possible in atypical liver hemangiomas after microbubble injection. Typical centripetal fill-in is the prevalent pattern and its evidence allows diagnosis.

Adult↗
PubMed2002

The feasibility of urethral color ultrasound imaging in the diagnosis of female intrinsic sphincter deficiency: preliminary results.

STUDY DESIGN: Prospective study. OBJECTIVES: To evaluate the feasibility of color ultrasound imaging of the urethra in association with UPP to diagnose intrinsic sphincter deficiency (ISD). SETTING: Italy. METHODS: We studied a group of 13 normal female volunteers (mean age 29 years) during the estrogenic phase and a group of 15 patients (mean age 63.9 years) with ISD. All patients and normal volunteers underwent color ultrasound imaging using a 4-7 MHz convex broad band transducer. Translabial sagittal scans of the urethra were obtained. The color ultrasound parameters were optimized for detection of parenchymal slow flows. A subjective score of the degree of vascularization along the entire urethra was established as follows: (a) minimal or absent (1), (b) poor (2), (c) moderate (3), (d) good (4). Statistical analysis, using the non-parametric Mann-Whitney rank sum test, was carried out to determine differences of ultrasound scores between volunteers and patients. RESULTS: The statistical evaluation showed that the differences between the ultrasound scores in the two groups was statistically significant (P<0.001). CONCLUSION: We affirm that color ultrasound imaging of the urethra seems to be feasible and useful in association with UPP in the diagnosis of ISD even if this echographic investigation needs further observations.

Adult↗
PubMed2000

Characterization of unifocal liver lesions with pulse inversion harmonic imaging after Levovist injection: preliminary results.

The aim of this study was to evaluate capabilities of pulse inversion harmonic imaging (PIHI) in characterization of unifocal liver lesions. We evaluated with PIHI (HDI5000, ATL, Bothell, Wash.) and spiral CT 46 consecutive patients with a single liver lesion identified by fundamental US [7 hepatocellular carcinomas (HCC), 2 cholangiocarcinomas, 7 focal nodular hyperplasias (FNH), 17 hemangiomas and 13 metastases]. The PIHI was performed before and 30 s, 2 and 4 min after bolus administration of Levovist (2.5 g, 300 mg/ml). Scans were digitally stored and reviewed using a dedicated software. Hepatocellular carcinoma was hyperechoic on 30-s scan, and hypoechoic (n = 5) or isoechoic (n = 2) on 2-min scan. Cholangiocarcinoma had inhomogeneous persistent enhancement. Focal nodular hyperplasia was hyperechoic (n = 5) or isoechoic (n = 2) on 30-s scan, hyperechoic (n = 4), isoechoic (n = 2) or slightly hypoechoic (n = 1) on 2-min scan. Large hemangioma revealed peripheral enhancement on 30-s scan which extended centripetally on 2-min scan. Small hemangioma appeared isoechoic on 2-min scan in all but two cases in which they were hypoechoic on 2-min scans and hyperechoic on 4-min scan. Metastasis was hypoechoic on all scans, 70% with rim enhancement. Similar changes in enhancement pattern have been observed at spiral CT. The 30-s and the 2-min scans revealed a conclusive importance in characterization of HCC, cholangiocarcinoma, and large hemangioma. The 2-min scan often furnished enough information for characterization of small hemangioma and metastasis. The 4-min scan allowed characterization of two hemangiomas which appeared hypoechoic on 2-min scans. In the other cases it did not provide further information. Diagnosis of FNH is usually reached with Colour Doppler US; PIHI should be used when colour Doppler is biased by artefacts or when colour Doppler findings are not characteristic. Our results seem to show that PIHI could be a valuable alternative diagnostic approach to spiral CT for unifocal liver lesion characterization. This hypothesis needs to be confirmed with an increased number of lesions.

Adult↗
PubMed1999

Detection of liver metastases with pulse inversion harmonic imaging: preliminary results.

The aim of this study is to evaluate capability of contrast enhanced ultrasonography (US) using pulse inversion harmonic imaging (PIHI) to detect liver metastases in comparison to fundamental B-mode ultrasound and spiral CT. Thirty-six consecutive patients with known malignancies and sonographically proved or suspicious liver metastases have been examined with fundamental B-mode US, with PIHI 2', 4' and 6' after Levovist injection and with four phase spiral-CT. Presence, conspicuity and number of lesions have been evaluated comparing PIHI with fundamental B-mode US and spiral-CT. A strong grey-scale enhancement of the liver parenchyma has been observed 2' and 4' after Levovist injection. The optimum parenchymal enhancement and contrast difference between liver and metastases was observed during the 2' measurements. PIHI revealed more lesions than fundamental B-mode US in 56 % of patients, while in 39 % and in 5 % revealed respectively the same number and fewer lesions. PIHI and spiral-CT were in agreement in 67 % of patients, while in 22 % and 11 % PIHI revealed respectively more and fewer lesions. PIHI accurancy presents restrictions in anterior superficial and in deep liver areas, whereas it may be superior to spiral-CT in studying sub-diaphragmatic liver regions.

Aged↗
PubMed1998

Transcranial Doppler: state of the art.

INTRODUCTION: Transcranial color Doppler sonography permits the accurate assessment of intracranial arteries. The latest Doppler units, using the color and power techniques, can show even very small flow volumes (1 x 1 mm). Low frequency (2-2.5 MHz) and very focused transducers are used in transcranial color Doppler. The skull is a very strong barrier for ultrasounds, which requires the use of some acoustic windows like some thin portions of the skull bone or some natural skull foramina. The use of echocontrast agents in color Doppler seems to increase the applications of transcranial studies. OBJECTIVE: (1) To report on transcranial color Doppler technique and findings. (2) To assess the role of contrast agents in the visualization of intracranial vessels. (3) To define the main indications of this technique. MATERIAL AND METHODS: The temporal, the orbital and the suboccipital are the main acoustic windows used for transcranial color Doppler studies. We use phased-array transducers (2-2.5 MHz) and, preferrably, the echocontrast agent. We examined 15 patients with severe internal carotid artery stenoses after the infusion of Levovist (Schering AG, Berlin, Germany) suspension (8 ml at 300 mg Galactose/ml, infused at 0.5 ml/s). RESULTS: Levovist infusion permitted to depict the main intracranial vessels in all cases. The middle and the anterior cerebral arteries are shown through the temporal window. The former is the main cerebral artery, it is the easiest to identify and presents the highest peak systolic velocity. The orbital window can be used to visualize the ophthalmic artery and the internal carotid artery siphon, while the vertebral and the basilar arteries are demonstrated through the suboccipital window. DISCUSSION: We report the most important findings and discuss the main indications of transcranial color Doppler studies. In addition to flow presence and direction, the main indices of arterial flow can be measured thanks to contrast agent administration, namely the peak systolic velocity, the end diastolic velocity, the resistance index and the pulsatility index. A morphological assessment of the Willis circle can also be carried out with color and power Doppler. Functional studies can be performed to assess the residual autoregulatory function of the cerebral circle in the patients with internal carotid artery stenosis or occlusion. The development of intracranial collateral circles can also be studied in these patients. Moreover, the M1 segment of the middle cerebral artery and the internal carotid artery siphon can be demonstrated directly. Transcranial color Doppler is also a useful tool to detect vasospasm after subarachnoid hemorrhage and to monitor blood flow velocity in the middle cerebral artery during carotid endarterectomy. The assessment of blood supply to arteriovenous malformations and to intracranial neoplasms is another application. CONCLUSION: With reference to internal carotid stenoses, the main applications of transcranial color Doppler are the study of intracranial vessels, of intracranial arterial stenosis, of arteriovenous malformations and of Willis circle aneurysms, as well as the monitoring of blood flow velocity during carotid endarterectomy. Echocontrast agents play an important role in the visualization of intracranial vessels.

Arterial Occlusive Diseases↗
PubMedDate not supplied

Color Doppler sonographic appearance of renal perforating vessels in subjects with normal and impaired renal function.

PURPOSE: The purpose of this study was to assess the prevalence and color Doppler sonographic characteristics of perforating vessels-small arteries and veins connecting the intrarenal vasculature with the capsular plexus-in healthy subjects, in hypertensive patients, and in patients with renal failure due to hypertensive nephroangiosclerosis or ischemic nephropathy. METHODS: Fifteen healthy subjects 24-34 years old, 15 healthy subjects 68-80 years old, 25 hypertensive patients, 25 patients with hypertension and chronic renal failure (15 mild, 10 severe), and 12 patients with hypertension and chronic renal failure and acute renal insufficiency due to ischemic nephropathy underwent color Doppler sonography of both kidneys. RESULTS: The few perforating arteries in healthy and hypertensive patients had various resistance indices and flow toward the capsule. Perforating veins in these patients were much more common than perforating arteries. Perforating arteries with a lower mean resistance index than the mean interlobar resistance index and flow toward the capsule were detected in 76% of kidneys in the patients with mild chronic renal failure and in 20% of those in patients with severe chronic renal failure. Only a few perforating veins were seen in patients with chronic renal failure. In 64% of the kidneys with renal artery stenosis detected in the patients with chronic renal failure complicated by acute renal insufficiency, there were perforating arteries with flow toward the kidney and a mean resistance index higher than the mean interlobar resistance index. CONCLUSIONS: Perforating vessels are recognizable using color Doppler sonography both in healthy subjects and in patients with renal failure. The prevalence and flow characteristics of perforating vessels differ between healthy subjects, patients with mild and with severe chronic renal failure, and patients with chronic renal failure complicated by acute renal insufficiency caused by renal artery stenosis.

Adult↗
PubMedDate not supplied

[Current role of color Doppler ultrasound in acute renal failure].

Acute Renal Failure (ARF) is characterized by a rapid decline of the glomerular filtration rate, due to hypotension (prerenal ARF), obstruction of the urinary tract (post-renal ARF) or renal parenchymal disease (renal ARF). The differential diagnosis among different causes of ARF is based on anamnesis, clinical symptoms and laboratory data. Usually ultrasound (US) is the only imaging examination performed in these patients, because it is safe and readily available. In patients with ARF gray scale US is usually performed to rule out obstruction since it is highly sensitive to recognize hydronephrosis. Patients with renal ARF have no specific changes in renal morphology. The size of the kidneys is usually normal or increased, with smooth margins. Detection of small kidneys suggests underlying chronic renal pathology and worse prognosis. Echogenicity and parenchymal thickness are usually normal, but in some cases there are hyperechogenic kidneys, increased parenchymal thickness and increased cortico-medullary differentiation. Evaluation of renal vasculature with pulsed Doppler US is useful in the differential diagnosis between prerenal ARF and acute tubular necrosis (ATN), and in the diagnosis of renal obstruction. Latest generation US apparatus allow color Doppler and power Doppler evaluation of renal vasculature up to the interlobular vessels. A significant, but non specific, reduction in renal perfusion is usually appreciable in the patients with ARF. There are renal pathologic conditions presenting with ARF in which color Doppler US provides more specific morphologic and functional information. In particular, color Doppler US often provides direct or indirect signs which can lead to the right diagnosis in old patients with chronic renal insufficiency complicated with ARF, in patients with acute pyelonephritis, hepatic disease, vasculitis, thrombotic microangiopathies, and in patients with acute thrombosis of the renal artery and vein. Contrast enhanced US is another useful diagnostic tool in patients with ARF which has been recently introduced in clinical practice. Microbubble administration may reduce technical failure in the evaluation of the renal artery. Moreover, perfusion defects due to stenosis or thrombosis of the renal segmentary vessels are better recognized. New diagnostic possibilities of enhanced US include evaluation of both cortical and medullar vessels, and functional evaluation of renal perfusion. Measuring the transit time of the microbubbles is useful for the diagnosis of renal artery stenosis and, in transplanted kidneys, for differential diagnosis between ATN and acute rejection.

Acute Kidney Injury↗
PubMedDate not supplied

[Magnetic resonance of the elbow: technique optimization and definitions of normal anatomical features and their variations].

INTRODUCTION: MRI is a very accurate technique to study the elbow joint, tendon, ligament and chondral structures. In the last years elbow disorders were described by several MR investigators, while we studied MR capabilities in depicting normal elbow anatomy. This investigation might permit the correct differentiation of normal from abnormal MR patterns. MATERIAL AND METHODS: Eleven healthy volunteers (6 men and 5 women, mean age: 27.5 years) were examined. All studies were performed on a 1.5 T imager (Magnetom SP 4000) with two types of receiver: the knee coil was used in 7 volunteers examined in the prone position, with the arm above their head, the elbow extended and the forearm supine and the shoulder coil was used in 4 volunteers examined in the prone position, with the arm above their head, the elbow flexed and the forearm prone. We acquired T1-weighted SE sequences (TR/TE = 690/15 ms, FA 90 degrees, MA 256 x 512, NEX 2,20 3-mm sections with .3-mm interslice gap, FOV 20-22 cm) on the axial, coronal and sagittal planes and T2-weighted GE sequences (TR/TE = 450/10 ms, MA 256 x 256, 3 NEX, 18 4-mm sections with .4-mm interslice gap, FOV 13-18 cm) on the coronal plane. Two MR-expert radiologists studied the images and identified the main anatomical structures of the elbow and 12 smaller reference elements (2 anatomical variants, 4 ligaments, 3 nerves and 3 arteries) describing their MR appearance and pointing out the most effective planes for their representation. Finally, the image quality of the knee coil was compared with that of the shoulder coil. RESULTS: All bones were clearly depicted on the coronal and axial planes, while the semilunar groove and its anatomical variants were best seen on the sagittal plane. The joint cartilage was best depicted on the coronal plane with T2-weighted GE sequences. Collateral ligaments were best seen with the elbow extended and the forearm supine (knee coil), on coronal T1-weighted SE images, where the radial and ulnar collateral ligaments were visible in 71.4% and 85.7% of the subjects, respectively. Annular ligaments, muscles and tendons were best demonstrated on the axial plane with the elbow extended and the forearm supine (knee coil), while the triceps tendon was best recognized on the sagittal plane with the elbow flexed and the forearm prone (shoulder coil). Vessels and nerves were also best seen on the axial plane with the elbow extended and the forearm supine; in particular, the median nerve was visible in 71.4% of the subjects. DISCUSSION AND CONCLUSION: MRI is very effective in representing elbow anatomical structures. Its accuracy depends on elbow (flexed or extended) and forearm (prone or supine) position. The coronal images with the elbow extended and the forearm supine (knee coil) are the most effective to show the ligaments and the joint surfaces between the radial head and the coronoid process of ulna with the capitellum and trochlea of distal humerus, while the axial images best depicted the muscles, vessels and nerves. The coronal and axial planes, with the elbow flexed and the forearm prone (shoulder coil) are poorly effective for anatomical detailing, even though this position is more comfortable for the patient, while the sagittal plane is best suited to depict the triceps tendon. This position may be used when the elbow cannot be fully extended or when the triceps tendon is studied.

Adult↗