[Study of the liver and the portal venous system with digital rotational angiography]. / Studio del fegato e del sistema venoso portale con angiografia digitale con rotazione.

PURPOSE: Digital subtraction angiography is of common clinical use for the evaluation of vascular disease. The rotation of the X-ray tube around the patient's body during contrast medium injection was first proposed in the early seventies in the neuroradiologic field; only recently it has been applied to the evaluation of vascular structures and abdominal parenchymatous organs. We investigated the potential clinical value of digital rotational subtraction angiography in the evaluation of the hepatic arteries and of the portal venous system. MATERIALS AND METHODS: Digital rotational subtraction angiography was performed in 46 patients (34 males and 12 females), mean age 59.3 years (range: 43-72). All the patients underwent digital rotational subtraction angiography after ultrasonographic, CT and/or MRI imaging for evaluation of hepatocellular carcinoma (31 patients) prior to trans-arterial chemoembolization, hepatic metastases from gastrointestinal cancer (9 patients) and pre-surgical study in portal hypertension (6 patients). Digital rotational subtraction angiography was performed using the following technical parameters: a maximum frame rate of 10 views per second, a 1024 x 1024 matrix, a rotation time of 5 seconds, a rotational arch of 90 degrees with a speed of 30 degrees/second. Digital rotational subtraction angiography of the liver was carried out after positioning of a Cobra angiographic catheter in the proper hepatic artery or in the left or right hepatic artery, and subsequent injection of 20-30 ml on contrast medium at a flow rate of 4-7 ml/sec. Conversely, in the portal study the catheter was placed in the splenic or superior mesenteric artery and contrast was administered at 10 ml/sec for an amount of 40-60 ml. Conventional, non-rotational angiography was always obtained with the same catheter and less contrast medium (15-25 at 4-7 ml/sec in the hepatic study, 25-40 ml at 5-7 ml/sec in the portal study). We have evaluated the diagnostic quality (rated as equal, superior or inferior) and the presence of image noise of digital rotational subtraction angiography when compared to digital non-rotational subtraction angiography. We also evaluated the tolerability and the mean time to perform the examination. RESULTS: Compared to non-rotational digital subtraction angiography, the diagnostic quality of digital rotational subtraction angiography was superior in 26 cases, equal in 20 and never inferior: these results are particularly evident in cine-mode. Diagnostic efficacy was similar in the arterial phase and generally better in the venous phase. Image noise was always perceptible, mostly in lateral and oblique views and is related to the patient's size. Noise especially hindered evaluation of the portal venous phase. Digital rotational subtraction angiography was well tolerated by all patients, although its most significative drawback was the prolonged apnea time required (about 8 seconds per single rotation) which can sometimes be difficult for elderly patients. Examination duration is about 5 to 10 minutes. Contrast medium doses required never exceeded 20-60 ml. DISCUSSION: Current evaluation of an hepatic lesion requires injections and multiple views to fully delineate arterial anatomy. This requires the radiologist to create a mental 3-D rendering based upon a 2-D view, obtained on the basis of the radiologist's experience. Rotational angiography, when reviewed in cine-loop, allows a better 3-D rendering than conventional angiography, increasing the advantages of the multiple views obtained from a single angiographic run and allowing an exact imaging of the course and direction of the hepatic arterial branching, making selective catheterization during trans-arterial chemoembolization or other interventional procedures easier. Magnification further improves the evaluation of a mass and of the arterial tree. In hepatic surgery, the most important problem is the precise knowledge of the segment involved and the position of the lesion inside the segment, since a mass in the middle of the segment requires a segmentectomy while a mass near the borders is treated by a larger resection. Digital rotational subtraction angiography improves the visibility of vascular anatomy, allows a better knowledge of hepatic artery branches and improves the angiographic investigation of the liver, permitting a correct spatial assessment. CONCLUSION: Digital rotational subtraction angiography is a useful tool for the evaluation of the liver as well as for transarterial chemoembolization or other interventional procedures. Images are obtained during a single contrast injection, with a better 3-D rendering of the hepatic artery and the portal venous system: no other method provides as complete a visualization of liver vascular anatomy after a single injection of contrast medium in one examination series. (ABSTRACT TRUNCATED)

Three-year follow-up of 62 cirrhotic patients with hepatocellular carcinoma treated with chemoembolization.

BACKGROUND: The aim of this study is to present our experience in 62 patients suffering from hepatocellular carcinoma (HCC) treated with transcatheter arterial chemoembolization (TACE) in two years. METHODS: TACE was performed with injection of doxorubicin mixed with lipiodol before embolization with spongostan. This procedure was repeated for 3 cycles almost. Follow-up was performed by US and CT and by assessment of clinical status and biochemical tests. TACE results were assessed comparing size, local spread and TACE technique with patients' survival. The lesion was single in 51 while multiple in 11. In 6 patients the lesion was greater than 5 cm while in 56 less than 5 cm. RESULTS: Overall survival rates were 95.7% at 6 months, 78.3% at 1 year, 46% at 2 years, 40% at 3 years. The best responses were obtained with single lesions smaller than 5 cm and treated with at least 3 cycles of TACE. CONCLUSIONS: We can conclude that TACE is an efficacious therapeutic choice in the HCC patients who cannot undergo surgery.

[Spiral computerized tomography in the diagnosis of acute occlusion of the abdominal aorta. A case report]. / La Tomografia Computerizzata spirale nella diagnosi dell'occlusione acuta dell'aorta addominale. Descrizione di un caso.

Aim of this report is to present a case of acute occlusion of the abdominal aorta recognized by spiral-CT. After a brief description of the etiology and pathology of abdominal aorta acute occlusion, stress is laid on diagnostic role of spiral-CT, based on personal and literature data. The advantage of spiral respect to non-spiral CT is the quicker examination time which is very important, mostly in emergencies. On the contrary, the diagnosis of acute abdominal aorta occlusion is not modified by volumetric CT respect to non-spiral and it is based on the absence of aorta contrast enhancement above the occlusion level.

[Computerized tomography of the lungs in patients with congenital immunodeficiency. Comparison with clinicoradiologic assessment]. / Valutazione con Tomografia Computerizzata del polmone dei pazienti con immunodeficienze congenite. Confronto con la valutazione clinico radiologica.

PURPOSE: Primary immunodeficiencies (PI) are a heterogeneous and relatively uncommon group of conditions. As a result of one or more immune system abnormalities, PI decrease the body resistance to infections. The respiratory tract is affected in most cases as a result of its natural exposure to pathogenic agents; repeated infections can lead to pulmonary alterations. We investigated the yield of High Resolution CT (HRCT) and Helical CT in pediatric patients with different PI and then correlated the CT patterns with the patients' clinical history and physical status. MATERIAL AND METHODS: We examined 19 pediatric patients with different types of PI. All patients presented recurrent infections (rhinosinusitis, bronchitis, bronchopneumonia) with cough and chronic catarrh for at least 3 months a year. Fifteen patients were examined with HRCT and 4 with Helical CT. Images were evaluated for presence and severity of alveolitis, bronchiectasis, peribronchial thickening, mucous plugs, air trapping, bronchiolitis, consolidation, abscesses, bullae, emphysema and fibrotic changes. All parameters were given a score and a partial and an overall score calculated for each parameter. All scores were compared to study the correlations between CT patterns, clinical history and patients' status and for possible characterization of the different groups by CT patterns. Finally, all alterations were classified by their anatomical distribution in each pulmonary lobe. RESULTS: Scores ranged 0 to 18, with a mean of 8.1 points. There were no correlations between CT patterns, patients' history and clinical status and any disease type. The midlobe was the preferential site for bronchiectasis while lower lobes were more involved by other conditions, such as consolidation, air trapping and alveolitis. CONCLUSIONS: Both HRCT and Helical CT proved to be useful tools for monitoring PI patients. The two techniques can be especially valuable in symptomatic patients with negative radiographic findings because they can show (non-)reversible damage, which helps improve planning of drug and/or physical therapy. The scoring system, even if not closely correlated with clinical signs, could be a major tool for PI follow-up and for monitoring treatment success.

[Unusual application of computerized tomography: the study of musical instruments]. / Un'insolita applicazione della Tomografia Computerizzata: lo studio degli strumenti musicali.

INTRODUCTION: We report on the use of CT in the study of bowed stringed instruments to assess structural defects and/or damage before proceeding to any repair. MATERIAL AND METHODS: Two antique masterpieces from the Castello Sforzesco Museum of Antique Musical Instruments were analyzed with CT. They were an exquisite wood and ivory guitar from Naples (Italy) and a very rare Giuseppe Guarneri "del Gesù" violin from Cremona (Italy), both crafted in the early years of the 18th century. We evaluated the wood thickness, the neck and its heel. In the wood structure we studied the course and thickness of hypo- and hyperdense lines. RESULTS: The examination showed three types of signs: normal wood structure: hypodense, thin, parallel lines; wormholes: hypodense lines with irregular course and variable thickness; previous repair signs: thin or thick more or less parallel hyperdense lines. CONCLUSIONS: The study confirmed that CT is a valuable tool to investigate normal structure, defects and damage, providing accurate information for the evaluation and repair of antique stringed instruments.

[Computer-assisted image postprocessing in intraoral digital radiography]. / L'elaborazione computerizzata delle immagini nella radiografia digitale endorale.

INTRODUCTION: Computer-assisted postprocessing was performed on selected digital dental radiographs using a professional software for photographic retouching. MATERIALS AND METHODS: The optical characteristics of 22 digital intraoral images (radio-videographies) taken on 18 patients were modified as regards their density and contrast values. Three different kinds of densitometric curves, corresponding to particular changes in post-processing parameters, were preliminary defined as the most effective for the demonstration of root canals and of alveolar bone. They were then applied to each X-ray image and the pictures thus modified were subsequently printed and read on a blind basis by three observers who considered the conspicuity of each structure of interest (root canals and alveolar bone). RESULTS: The results, submitted to statistical analysis, demonstrate that computer-assisted postprocessing can improve the visual yield and the diagnostic effectiveness of digital dental images in 67% of cases for the periapical bone and in 86% of cases for the root canals. CONCLUSIONS: The most effective sets of post-processing parameters established for each structure of interest are proposed together with a pre-programmed function to be introduced into the software of digital radiographic equipments.

[Splenomegaly and hypersplenism in cirrhotic patients before and after orthotopic liver transplantation]. / Splenomegalia e ipersplenismo nei pazienti cirrotici prima e dopo trapianto ortotopico del fegato.

PURPOSE: To measure the spleen length in patients with cirrhosis and portal hypertension with US and compare the measurements before and after orthotopic liver transplantation. To correlate splenic measures with laboratory data and Doppler flowmetry (mean portal vein flow velocity). MATERIALS AND METHODS: May, 1993, to January, 1997, fifteen patients with cirrhosis, portal hypertension and splenomegaly were examined and underwent orthotopic liver transplantation. The spleen length was measured before and after transplantation in 15/15 patients and it was also measured twice after transplantation in 10/15 patients. The mean portal venous flow velocity was measured before and after transplantation in 10/15 patients. The results were analyzed using the Student's t-test for paired and unpaired data; the association between the variables was evaluated by linear regression analysis; two-tailed p values were used. RESULTS: At the first control after orthotopic liver transplantation (mean time from transplantation 5.5 +/- 2.6 months; range 2.5-12.5 months) a significant decrease was found in spleen length (179 +/- 32 to 149 +/- 30 mm, p = .0001; mean percent decrease = 16.7 +/- 9.9%), hypersplenism disappeared in 9/13 cases, mean portal venous flow velocity, measured in 10/15 patients, showed an increasing trend (16.0 +/- 9.0 to 22.3 +/- 9.0 cm/s). At the first control the correlation between the values of mean portal flow velocity measured before and after transplantation was not significant (r = .558, p = .0939); the same was true for the correlation between mean portal flow velocity and spleen length. The second measurement of the spleen length after transplantation (mean time from the first follow-up 18.1 +/- 7.8 months; range 6.4-32.8 months) in 10/15 subjects demonstrated no significant changes in the spleen dimensions relative to the first examination (139 +/- 24 mm to 138 +/- 26 mm), and in 1/10 case hypersplenism disappeared. CONCLUSIONS: The measurement of the spleen length is proposed for the follow-up of the patients with cirrhosis and hypersplenism before and after orthotopic liver transplantation. In our study, the mean decrease in spleen length was 17% in the period from transplantation to the first US examination. In the patients who underwent a second measurement after transplantation no significant change in spleen length was observed.

[Survival of 184 patients with hepatocellular carcinoma in cirrhotic liver treated with chemoembolization. A multicenter study]. / La sopravvivenza di 184 pazienti con carcinoma epatocellulare nel fegato cirrotico trattati con chemioembolizzazione. Studio multicentrico.

INTRODUCTION: We report the results of a multicenter study of 184 cirrhotic patients with hepatocellular carcinoma (HCC) treated with transcatheter arterial chemoembolization (TACE) and compare our results with those reported in the literature. MATERIAL AND METHODS: We treated 184 cirrhotic FNB-proved HCC patients with TACE in a 2 years' period; 159 were men and 25 women and their mean age was 59 years (range: 46-75 years). TACE was performed with selective or superselective injection of Doxorubicin chlorhydrate (20-50 mg) mixed with Lipiodol Ultrafluid before embolization with Spongostan. This procedure was repeated after 4-6 weeks for at least 3 cycles. Follow-up was performed by means of periodic US, CT and MR scans and by assessment of the clinical status and serum biochemical tests--alpha-fetoprotein, platelet and blood cell counts, protein electrophoresis, bilirubin and other standard liver and renal function tests. TACE results were assessed comparing site, size and local spread of tumor and TACE technique (lobar or segmental, number of performed procedures) with survival in each patient. The lesion was single in 85 (46.2%) and multiple in 99 (53.8%) patients. It exceeded 5 cm in 128 patients (69.5%) and was < 5 cm in 57 (30.5%). RESULTS: Angiography, CT and MRI showed complete necrosis in 148 patients (80.4%) and an unchanged pattern in 36 (19.6%). Overall survival rates were 95.7% at 6 months, 78.3% at 1 year, 46.0% at 2 years, 40.0% at 3 years. The best responses were obtained with lesions < 5 cm--with 100% survival at 6 months, 94.8% at 12 months, 71.4% at 18 months, 54.7% at 24 months and 50.0% at 36 months. Other factors affecting treatment response were singleness of lesion (96.4% at 6 months, 93.9% at 12 months, 71.4% at 18 months, 58.9% at 24 months, and 50.0% at 36 months) and at least 3 cycles of TACE (100% at 6 months, 87.8% at 12 months, 70.1% at 18 months, 48.7% at 24 months and 37.5% at 36 months). Abdominal pain and fever were the most frequent complications, particularly in the first TACE procedure, but both were mild and transient. Lipiodol cholecystitis was found in 3 patients but they were asymptomatic. No patients had evidence of cardiac toxicity or experienced significant leukopenia or thrombocytopenia as a result of systemic toxicity from Doxorubicin. CONCLUSIONS: We can conclude that TACE proves to be an efficacious treatment in the HCC patients who cannot undergo surgery.

[Digital rotational angiography in the study of vascular diseases: technical note and initial clinical applications]. / L'angiografia digitale con rotazione del tubo radiogeno nello studio delle malattie vascolari: note di tecnica e prime applicazioni cliniche.

INTRODUCTION: Digital rotational angiography is a technique characterized by a C-arm acquiring images as it rapidly rotates around the patient. We studied the clinical potentials of this technique in the assessment of vascular diseases of the abdominal aorta and of the carotid, lower limbs and renal arteries. MATERIAL AND METHODS: We examined 108 patients (66 men and 42 women; mean age: 54.3 years, range: 34-69): 42 had vascular diseases in the carotid arteries, 47 in the abdominal aorta and lower limbs and 19 in the renal arteries. All the patients underwent digital rotational and non-rotational angiography and we analyzed the diagnostic yield, amount of contrast agent and the utility of additional views for each technique. All the examinations were reviewed with(out) subtraction, in cine-loop mode and frame by frame, as well as with(out) magnification. Finally, we considered background noise in both rotational and non-rotational images. RESULTS: The diagnostic quality of the digital rotational technique was always the same as or superior to that of the non-rotational technique. The former allows better 3D rendering, especially when viewed in the cine-loop mode; the examination is shorter and less contrast agent is needed. In contrast, image noise was increased, especially in lateral and oblique views. Digital rotational angiography was fairly well tolerated but the long breath-hold required was a problem especially to elderly patients. CONCLUSIONS: Digital rotational angiography is a useful tool to study vascular diseases in the carotid arteries and lower limbs using a lower radiation dose and less contrast agent than non-rotational examinations. As for the abdominal aorta and renal arteries, the rotational technique can be a valid adjunct to the conventional one.

[Diagnostic imaging in the selection of candidates to orthotopic transplantation of the liver. Experience at a hospital lacking a transplantation department]. / Diagnostica per immagini nella selezione dei candidati al trapianto ortotopico del fegato. Esperienza in un ospedale non dotato di centro per trapianti.

We report the experience of our general hospital in selecting the patients for orthotopic liver transplantation (OLT). Fifty-one patients with cirrhosis were examined and 20 of them submitted to OLT from August, 1992, to November, 1995. For liver studies, the 20 transplant recipients were examined with US and plain and dynamic CT; 15/20 were submitted to CTAP, 10/20 to Lipiodol CT and 17/20 to angiography. The accuracy of these techniques in HCC detection was assessed by correlation with resected whole livers. The accuracy of duplex Doppler and color flow Doppler for portal and/or mesenteric vein thrombosis was evaluated by correlation with resected livers, CT and angiographic findings. Pathologic examinations diagnosed HCC in 5/20 transplant recipients: 2 lesions (1.5 cm and 2 cm; 2 cm and 3.5 cm) were found in 2 resected specimens (total hepatectomy) and 1 lesion was found in 3 cases (2.5 cm, 1.5 cm, 1 cm). The sensitivity of US, plain and dynamic CT in identifying HCC patients was 20%; US and CT specificity rates were 100% and 87%, respectively. CTAP sensitivity was 75% and the sensitivity of Lipiodol CT and angiography was 100%. Therefore, in our series, US was poorly sensitive in the detection of liver cancers, which may depend on the small number of patients, lesion size (< or = 3.5 cm) and the radiologists ignoring clinical and laboratory data on purpose. Nevertheless, the patients with a single HCC not exceeding 5 cm phi or with no more than 3 tumors, none of them exceeding 3 cm phi, are generally considered eligible for transplantation: therefore, our patients chosen for OLT on the basis of US and CT findings were actually eligible for transplantation in spite of US and CT false negative results. At US, the portal vein had an average caliber of 13.5 +/- 2.5 mm in 21/51 patients; the average caliber of the common hepatic artery was 6 +/- 1.5 mm in 49/51 patients; average spleen length was 174 +/- 38 mm. US showed ascites in 28/51 cases. In conclusion, considering also the long stand-by list for OLT, the first selection of transplant candidates could be performed with US and color flow Doppler, plain and dynamic CT. The patients who are ruled out as candidates for OLT on the basis of the findings of these imaging techniques and of clinical and laboratory findings are submitted to no further examination and referred to the transplantation unit. Otherwise, if conventional and color flow Doppler US and conventional CT are not enough to exclude a patient from OLT, the subject is submitted to more invasive (angiography, CTAP, Lipiodol CT) or less widespread (spiral CT, MRI) techniques.

[Digital radiology in dentistry: experience with direct intraoral techniques (radiovideography)]. / La radiologia digitale nell'odontoiatria: esperienza con le tecniche d'acquisizione endo-orale diretta (radiovideografia).

The aim of this paper was to discuss the techniques for intraoral digital radiography (radiovisiography) and to compare their accuracy in dental radiographical diagnosis. Emphasis was given to their potential applications in oral radiology. Radiovisiography was compared with intraoral films and electronic magnifications from digital panoramic radiographs in 38 patients, for a total amount of 36 caries, 27 periapical conditions and 58 metal implants. Moreover, the accuracy of the measurements made with the three techniques was assessed on a specimen of mandibular and maxillary arches containing 28 extracted teeth with endodontic files of known length. Radiovisiography was as effective as intraoral films and more effective than digital panoramic radiographs in the diagnosis of caries and periapical lesions. Nevertheless, it produced a significant magnification and yielded unreliable measurements of root canals and metal implants. Radiovisiography is very easy to use and does not require dark room procedures nor chemicals of any kind. In addition, it reduces patient's X-ray exposure by over 50% with respect to film studies. For these reasons, this technique seems to be worthy of widespread use in dental radiography, with the exception of the conditions requiring an exact measurement of working length.

[The measurement parameters in dental radiography: a comparison between traditional and digital technics]. / Parametri di misura nella radiografia dentale: confronto fra tecniche tradizionali e digitali.

Digital and conventional techniques for dental, panoramic and intraoral radiography, were compared to assess measurement accuracy. The study was carried out on two plastic models of maxillary and mandibular arches, each containing 14 teeth extracted and positioned in their anatomical site. The teeth were prepared by opening the pulpal cavity and inserting endodontic wires within the canals. Intraoral x-ray images were taken with long-cone technique using a commercial high-resolution film and with a charge coupled device (CCD) sensor (radiovisiography). The models were then submitted to panoramic tomography with photostimulable phosphor plates. The length of the canals was measured on each image and compared to the length of the inserted wires. For the digital pictures, the measurement was performed directly on the monitor with the aid of electronic calipers. Magnification averages 3.40%, 9.47% and 14.11% for anterior teeth in intraoral radiography, in radiovisiography and panoramic radiography, respectively. The results demonstrate the presence of some degree of magnification for every radiographic procedure. This effect becomes statistically significant for both radiovisiography and digital panoramic techniques, especially in the latter. In spite of their well-known practical and dosimetric advantages, digital techniques in dental radiology must be used carefully whenever a reliable measurement is required.

[A comparison between endoral radiography and electronic magnification of digital orthopantomography]. / Confronto tra radiografia endo-orale e ingrandimento elettronico da ortopantomografia digitale.

We compared the electronic magnifications obtained from digital panoramic radiographs with intraoral radiographs with a new high resolution film. Fifty-two patients were submitted to both examinations--76 comparative studies and 217 teeth studied in all. The two techniques appeared substantially comparable in terms of diagnostic effectiveness. The measurement of the alveolar ridge was strictly equivalent for the two examinations (< 1 mm disagreement in 80% of cases). The profile of lamina dura and the image of the radicular canal were better depicted with intraoral films. A useful advantage offered by digital images was the possibility of recognizing the soft tissues. In dental caries intraoral films was more effective than digital images and were correctly depicted small carious cavities (< 2 mm depth, 87 vs 74%). Digital panoramic radiography can be considered a promising alternative to panoramic film. Its electronic magnification may be a valuable diagnostic complement to intraoral films for the study of periodontal disease, but it cannot replace intraoral films for the assessment of fine dental details, small caries in particular. The new intraoral film was substantially equivalent to digital images for the assessment of bone lesions and of periodontal disease.

[The spatial resolution of the digital storage phosphor system. The monitor and film compared]. / La risoluzione spaziale del sistema digitale con fosfori a memoria. Monitor e pellicola a confronto.

The physical characteristics of radiographic images, namely spatial resolution and contrast, have obvious effects upon diagnostic image usefulness. We investigated the spatial resolution of both radiographs and magnified digital obtained with a storage phosphor system, in comparison with a film-screen combination. This study was carried out on the conventional radiographs of a phantom grid 0.5 mm thick, with resolution ranging from 0.5 to 10 lp/mm. Each examination was compared at naked eye and with the electronic evaluation of a region of interest on both standard and magnified views or by digitization with a charge coupled detector (CCD) television camera followed by the computing of the modulation transfer function curve. Our results demonstrate a higher spatial resolution of direct magnification, on both digital and film-screen pictures (over 5 lp/mm). On the contrary, the electronic magnification on the monitor yields the same spatial resolution as non-magnified digital images (up to 4.3 lp/mm). By selecting appropriate regions of interest, we could demonstrate the compression of the non-magnified images on the monitor. The modulation transfer curves show that direct magnification yields higher spatial resolution than electronic magnification and non-magnified views. Viewing electronically magnified images on the monitor yields the same resolution as contact radiographs: the monitor offers the advantage of an easier study of the regions of interest.