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G Maresca

Publications and source records attributed to G Maresca.

At least 37 records · Page 2Linked to original sources
PubMed1996

[T2-dependent sequences in the study of hepatic focal lesions: comparison of the conventional spin echo sequence and the 0.5 T fast spin echo].

T2-weighted spin echo MR images are widely used in the detection and characterization of focal liver lesions. The main pitfall of this technique is its relatively long acquisition time. Fast spin echo sequences can provide the same contrast as conventional T2-weighted SE images in a shorter scanning time. Our study prospectively compared the effectiveness of T2-weighted conventional spin echo (CSE) versus fast spin echo (FSE) sequences in MRI of focal liver lesions. We examined 24 patients with this condition. All lesions were submitted to percutaneous biopsy and to the diagnostic gold standard technique, which was intraoperative US (13 patients), Lipiodol CT (10 patients) or 6-month follow-up (1 patient). MR images were analyzed from both a quantitative (signal-to-noise and contrast-to-noise ratios) and a qualitative viewpoints (overall image quality, lesion detection rate, number of lesions as compared with the gold standard, lesion conspicuity, internal features and the absence of artifacts). There was no statistically significant difference in contrast-to-noise ratio between the two sequences (p = 0.713). In the qualitative analysis, CSE sequences were superior to FSE for overall image quality in 50% of cases, for lesion conspicuity in 41.5% of cases and for internal features and the absence of artifacts in 46% of cases, FSE sequences had a higher detection rate in 17% of cases, even though both types of sequences underestimated the number of lesions in 29% of cases, as compared with the gold standard. To conclude, FSE sequences were inferior to CSE for image quality, lesion conspicuity, internal features and the absence of artifacts. FSE sequences were superior in the detection and characterization of fluid and nearly fluid lesions.

Adult↗
PubMed1996

[Synovial cyst of the cruciate ligament. Findings with magnetic resonance in 8 symptomatic cases].

Intraarticular ganglion cysts are uncommon findings: only 30 cases have been reported since the first paper by Caan in 1924 and they were all associated with cruciate ligaments. Many different cystic or pseudocystic lesions are found in articular knee conditions: the most common cystic lesions are popliteal cysts (Baker's cysts), followed by synovial pseudocysts of the posterior cruciate ligament, meniscal cysts and, finally, ganglion cysts of the cruciate ligaments. In our series of 1600 knee MR exams carried out in our MR department since June, 1994, we have found 8 ganglion cysts of the cruciate ligaments. MR studies are always performed on a dedicated 0.2-T permanent magnet (Artoscan, Esaote Biomedica, Genoa, Italy). Five patients were operated on with arthroscopy. The ganglion cysts affected the anterior cruciate ligaments in 4 cases and the posterior cruciate ligaments in 4 cases. The symptoms were mainly pain radiating to the medial side and worsening in forced flexion or extension. The diagnostic suspicion was meniscal tears in 4 patients, chondral lesions in 3 and a loose intraarticular body in one patient. The shape and structure of ganglion cysts in the cruciate ligaments are clearly depicted with MRI. The ganglion cysts in the anterior cruciate ligaments are usually spindle-shaped and within the ligament, while those in the posterior cruciate ligaments have a well-defined outline, with multilocular appearance, and they are usually localized along the ligament, most often on the dorsal aspect. MR signal studies show intermediate signal intensity on SE T1-weighted images and markedly increased signal intensity on SE T2-weighted images. These typical patterns may change depending on lesion content, for instance in the presence of hemoglobin due to an associated angioma. The origin of ganglion cysts in the cruciate ligaments is still unknown, even though many theories have been suggested, including a synovial herniation in ligament fibers, the ectopic inclusion of synovial tissue, a posttraumatic connectival degeneration and, finally, the proliferation of totipotent mesenchymal cells. From a histologic point of view, "synovial ganglion" is a much better definition than "synovial ganglion cyst", because the typical wall of real synovial cysts is missing. The MR patterns are typical of the morphological features described and of the presence of high protein fluid content.

Adult↗
PubMed1995

Healing of the patellar tendon after harvesting of its mid-third for anterior cruciate ligament reconstruction and evolution of the unclosed donor site defect.

The purpose of this study was (a) to evaluate by ultrasonography the healing of the patellar tendon after its mid-third was removed for anterior cruciate ligament (ACL) reconstruction in two randomized groups of patients in whom the tendon donor site was either left open or closed; (b) to compare clinical, radiographic, and isokinetic studies of these two groups to evaluate the incidence of patellofemoral disorders. We performed 61 ACL reconstructions (22 males, 39 females) using the arthroscopically assisted in-out technique. All operations were performed by the same surgeon, and the patients were all subjected to the same postoperative protocol. The tendon defect was left open in 25 subjects (group A) and was closed in 36 subjects (group B). Postoperative patellar tendon behavior was evaluated in these two groups by ultrasonography at 3, 6, 9, and 12 months. The vertical position of the patella was measured in the follow-up lateral view at 45 degrees of flexion and compared to that of the untreated knee. A clinical evaluation was performed throughout the follow-up period, and patellofemoral problems (pain, stiffness, patello-femoral crepitus) were evaluated and recorded using a modified Larsen and Lauridsen rating scale. Isokinetic evaluation was carried out at 6 months, and a quadriceps index of the two groups was recorded. Ultrasonography showed that healing of the patellar tendon initially progressed with a compensatory hypertrophy in width and thickness. The width was greater in group B (P < 0.01). In group A we observed in the cross-sections a characteristic image of two cords separated by a low signal bridge which we defined as a "binocular pattern." Areas of high ultrasound signal intensities persisted after 1 year in the open group; such areas were filled with scar tissue. In the closed group the ultrasound tendon signal returned to normal at 1 year. At 6 months the clinical, radiographic and isokinetic findings did not significantly differ between the open and closed groups. We conclude that defect closure after patellar tendon harvesting does not significantly influence the extensor apparatus.

Adolescent↗
PubMed1995

[The tissue characterization of focal liver lesions with magnetic resonance imaging].

This study was aimed at assessing the accuracy of Magnetic Resonance Imaging (MRI) in the characterization of focal liver masses. We prospectively examined 51 patients with focal liver masses: the morphological features were investigated with different pulse sequences and the functional characteristics were studied after the i.v. administration of Gd-DTPA (2 mmol/kg). MR findings were compared with those of gold standard methods, i.e., percutaneous biopsy, surgery or, for hemangiomas, 99mTc-labelled blood cell liver scintigraphy. All hemangiomas presented with typical features: signal intensity was very high on long TE images (> 140 msec) and a globular enhancement pattern, with centripetal progression, was observed after dynamic studies. This signal pattern on T2-weighted images is highly indicative of hemangioma. Five of 7 focal nodular hyperplasias (71%) were isointense with hepatic parenchyma on all pulse sequences; the central scar was observed in 5/7 cases on short TR/TE images and in all cases on long TR/TE images in 16/17 cases (94%). High signal intensity on T1-weighted images was statistically significant for HCC. A pseudocapsule was observed in 12 cases (70%). A mosaic pattern on T2-weighted images was observed in 3 cases. Seventy-four per cent of HCCs exhibited signal enhancement during the arterial phase of the dynamic study. Metastases presented a uniform pattern, i.e., they were hypointense on T1-weighted and hyperintense on T2-weighted images in 12/13 cases (92%). A central hypointense area on T2-weighted images is indicative of coagulative necrosis. A lesion with these morphological features and hypovascular signal is suggestive of metastasis.

Biopsy, Needle↗
PubMed1995

[The tissue characterization of focal liver lesions by color Doppler echography].

To investigate color-Doppler capabilities in tissue characterization, 47 hepatic lesions were studied. The real-time morphologic appearance of the lesions was studied first and then color flow images were acquired, assessing color areas and the distribution of blood flow for each lesion. For quantitative Doppler study, the color Doppler signal was used as a guide to obtain the Doppler spectrum and to measure flow velocities and pulsatility index (PI) values. Data were plotted and analyzed statistically; criteria for differentiating malignant from benign hepatic tumors and the patterns suggestive of either condition were proposed. Absolutely no Doppler signal was observed in avascular or necrotic lesions and in low-flow tumors, e.g., metastases (10%) and hemangiomas (63%). Many color signals at the periphery and within tumor masses were observed in highly vascular lesions, e.g., hepatocellular carcinomas (60%) and focal nodular hyperplasia (80%). Multiple afferent vessels and a "basket-like" pattern were detected in a high percentage of hepatocellular carcinomas. High-flow velocities (> 0.85 m/s perilesional systolic velocity and > 0.80 m/s intralesional systolic velocity) and high PI values (> 1.5 perilesional PI and > 0.90 intralesional PI) are suggestive of malignancy. Particularly, 0.90 intralesional PI cutoff value exhibits 89% specificity and 82% sensitivity in benign versus malignant differential diagnosis. Our results suggest that color-Doppler US is a useful means of studying the hemodynamics of hepatic tumors which increases US diagnostic accuracy.

Diagnosis, Differential↗
PubMed1995

[Color Doppler echography in the tissue characterization of renal masses].

To investigate color-Doppler US capabilities in tissue characterization, 42 renal masses were studied from November, 1993, to July, 1994. B-mode morphologic patterns were studied first and then integrated with color flow patterns; color areas and blood flow distribution were assessed for each lesion. Color signals were used as a guide to obtain arterial and venous Doppler spectra and to calculate flow velocities and pulsatility index (PI). Based on the us morphologic appearance, the 42 lesions were divided into 3 groups: A) lesions with morphologic and volumetric patterns of malignancy; B) small lesions (< 3 cm, > 3 cm < 5 cm); C) complex cysts. Data were organized and analyzed statistically; some findings were found to be typical of malignancy: hypervascularity, intralesional arterial signals with high flow velocities (systolic peak cut-off: 0.3-0.4 m/sec), high PI values (> 1) and, finally, color signals inside complex cysts. Our results suggest that color-Doppler US is a useful tool to assess renal masses vascularity, with the color-Doppler technique increasing US diagnostic accuracy. Nevertheless, small lesions need more careful study because their features are poorly demonstrated even with CT and MRI.

Adenocarcinoma↗
PubMed1994

Color Doppler ultrasonography in the differential diagnosis of focal hepatic lesions. The SH U 508 A (Levovist) experience.

The differential diagnosis of focal hepatic lesions is a current problem even though many study methods are available. Color Doppler US has been recently suggested as a diagnostic technique capable of depicting lesion vascularization patterns to better understand lesion nature. However, this examination is often difficult and long. In this study, we investigated the role of a US contrast agent SH U 508 A (Levovist) enhancing the color Doppler signals for easier and better depiction of lesion vascularization. Seventy-four patients with one or more focal hepatic lesions (mean diameter: 5.6 cm) were examined. The lesions were 38 HCCs, 4 cholangiocarcinomas, 1 intrahepatic biliary duct carcinoma, 1 case of multiple adenomas, 2 regenerations nodules in cirrhosis, 2 cases of FNH, 18 metastases and 8 hemangiomas. In 54 cases the US contrast agent allowed the visualization of some vessels inside the lesions which had been missed at baseline examinations. Moreover, the vessels which had been depicted on baseline images were better demonstrated. In all but one patient with severe hepatic steatosis, normal parenchymal vessels were markedly enhanced. Our results in the different kinds of tumors are here reported.

Color↗
PubMed1993

[Echo-Doppler in the study of pre- and post-hepatic portal hypertension].

Portal hypertension is due to a number of pathologic processes; these conditions cause hypertension mostly by hindering the portal flow. The obstacle to portal flow may be located at three different levels--i.e., subhepatic, intrahepatic and suprahepatic. The intrahepatic obstacle is observed in 95% of patients with portal hypertension, while the extra-hepatic causes are rare. This paper is aimed at assessing the diagnostic capabilities of color-Doppler US in the evaluation of pre- and posthepatic portal hypertension. This technique, combining morphologic and Doppler data, allows hypertension to be demonstrated and its degree to be assessed. Color-Doppler US can also define the intra/extrahepatic cause and the level of the obstacle to portal flow. In the diagnosis of the involved processes, the role of color-Doppler US is discussed and compared to the roles of other techniques.

Budd-Chiari Syndrome↗
PubMed1990

Plasma and urinary growth hormone and insulin-like growth factor I in children with chronic renal insufficiency.

We investigated the plasma and urinary growth hormone (GH) levels, and plasma insulin-like growth factor (IGF-I) in 15 (8 prepubertal and 7 pubertal) subjects with chronic renal insufficiency. Four of our 7 pubertal patients had a short stature (standard deviation score from -2.7 to -4.0). Significantly increased plasma GH and IGF-I levels were found in pubertal subjects alone (p less than 0.05). The urinary GH levels was significantly increased in prepubertal and pubertal subjects (p less than 0.001 and 0.05, respectively). A significantly inverse correlation between urinary GH excretion and creatinine clearance was found (r = -0.55; p less than 0.05). Increased plasma GH, IGF-I and urinary GH levels seem to suggest a complex alteration of GH and somatomedin metabolism in central and peripheral (receptor) cells.

Adolescent↗
PubMed1988

Recurrence of ovarian and uterine neoplasms: diagnosis with transrectal US.

Twenty-one patients with clinically suspected recurrence of ovarian (n = 3) or uterine (n = 18) carcinoma were examined with suprapubic ultrasound (US) and transrectal US with high-frequency linear probes. The examinations were performed 3, 6, 9, and 15 months after surgery and radiation therapy. Eight patients underwent radiation therapy before surgery and ten after surgery; three underwent only surgery. Criteria for recurrence included increased anteroposterior diameter of the vaginal cuff (greater than 2.2 cm); structural alterations or presence of a mass in the vaginal cuff; and infiltration of the rectovaginal septum, bladder, and parametria. Transrectal US findings were true positive for recurrence in nine cases, true negative in ten, and false positive in two. US findings were true positive in three cases, true negative in seven, false positive in two, and false negative in three. In six cases results from US were technically poor, and no diagnosis could be made. Transrectal US was highly sensitive in detection of pelvic recurrent carcinomas, while US had little diagnostic value. The authors believe transrectal US can replace US in the evaluation of patients at risk for recurrent pelvic neoplasm.

Adult↗
PubMed1988

[Embolization of the splenic artery in cirrhotic patients with portal hypertension. Ultrasound results and follow-up].

Over the last four years the authors performed transcatheter embolization of the splenic artery by Gianturco coils in 32 consecutive cirrhotic patients with portal hypertension, splenomegaly, cytopenia and gastro-esophageal varices endoscopically proved. This procedure was especially useful for treatment of splenomegaly and cytopenia because a constant reduction of spleen dimensions and increase in platelet count were registered. The effectiveness of transcatheter embolization and follow-up are based on clinic, hematologic and sonographic findings. We believe sonographic monitoring to be very useful both to evaluate splenomegaly and signs of portal hypertension and to reveal splenic complications (abscesses). We never registered severe complications.

Adult↗
PubMed1987

[Hemobilia: comparison of diagnostic technics. Considerations on 14 patients].

Fourteen cases of hemobilia of traumatic (six), vascular (six) or neoplastic (two) origin were reviewed. Eleven patients obtained correct diagnosis only be integration of at least two diagnostic procedures out of Ultrasonography, Computed Tomography, arteriography and cholangiography. Although US and CT are extremely useful as screening procedures, correct diagnosis should be only possible by integration of more diagnostic technics. Arterial embolization represents a successful alternative to surgical intervention; moreover US may also be helpful for follow-up of treated patients.

Cholangiography↗
PubMed1986

Sonographic patterns in splenic infarct.

The sonographic findings in eight cases of splenic infarct at their onset and at different phases of their development have been retrospectively analyzed. A wide range of appearances was seen (single or multiple, rounded or wedge-shaped, echo-free, hypoechoic, and hyperechoic lesions). In our opinion, such variable appearances are related to the age of the infarct (hypoechoic or echo-free in the earlier stages, hyperechoic in healed infarcts). A presumptive diagnosis is possible in the earlier stages since the detection of changes (in echogenicity and/or in size) over a period of time strongly suggests an infarct. On the other hand, a hyperechoic wedge-shaped lesion is fairly typical of healed infarcts.

Adult↗
PubMed1986

[Ultrasonic diagnosis, staging and follow-up of prostatic neoplasms].

120 patients with clinical suspected prostatic neoplasm were evaluate by transrectal linear sonography. 26 normal glands, 57 hypertrophic adenomas and 37 adenocarcinomas were recognized. We had 17 false positive cases for adenocarcinoma in hypertrophic adenomas. We had no false negatives. All diagnosis were confirmed bioptically, by CT or surgically. The findings of 37 adenocarcinomas are examined. The US criteria for early diagnosis (T1-T2), advantages and limits of transrectal linear probe in staging and follow-up, are discussed.

Adenocarcinoma↗