Iodine-based radiographic contrast medium may precipitate metformin-associated lactic acidosis in diabetic patients. A case report, literature review and practical approach.

Lactic acidosis in diabetic patients undergoing metformin therapy is a widely recognized, rare but usually serious adverse event, particularly in presence of comorbidities such as cardiorespiratory disease, sepsis and renal failure. As demonstrated by the case of an elderly woman presented, administration of radiographic iodine-based contrast agents may precipitate lactic acidosis through worsening of renal function. Awareness of this condition, identification of at-risk patients, adequate prevention following published guidelines, early diagnosis and treatment including hemodialysis are necessary to avoid a fatal outcome.

Acute adverse reactions to radiographic iodinated and gadolinium-based contrast media: incidence, risk factors and premedication: from published evidence to a practical approach.

Although relatively uncommon especially in their severe manifestations, adverse reactions (ARs) to radiographic contrast media (CM) may represent a source of concern to both physicians and patients because of the large number of CT and MR imaging procedures daily performed. In this paper the current literature is reviewed regarding incidence and risk factors for acute ARs to both iodinated and gadolinium-based CM, and about the usefulness of pharmacological premedication to reduce risk. A practical approach for everyday clinical practice is proposed.

Extrahepatic recurrence and second malignancies after treatment of hepatocellular carcinoma: spectrum of imaging findings.

PURPOSE: To describe diagnostic imaging features (with a focus on CT findings) of extrahepatic relapses of treated hepatocellular carcinoma and to propose a post-treatment follow-up protocol. MATERIAL AND METHODS: During a six-year span, 226 patients (aged 32-88 years) with chronic hepatitis/cirrhosis were diagnosed as having hepatocellular carcinoma confined to the liver and treated percutaneously with radiofrequency (RF) ablation. A total of 313 treatment sessions were performed. Post-therapeutic follow-up is based upon clinical evaluation, laboratory and imaging (with CT holding the key role) studies. RESULTS: Mean duration of follow-up was 17 months. After successful treatment, actuarial probability of neoplastic relapse is 30.7% after 1 year and 58.5% after 2 years. Eighty-eight patients had recurrence of hepatocellular carcinoma after a variable time interval (mean 7.3 months). Extrahepatic neoplastic relapse was observed in 14 patients, half of these without active hepatic disease. Distribution of extrahepatic sites of recurrence was as follows: abdominal lymph nodes (6 cases), bone (3), peritoneum (2), adrenal (2), lung (1). Five patients (2.2%) had a second primary neoplasm. CONCLUSIONS: Extrahepatic hepatocellular carcinoma is uncommon and occurs in advanced stages, but may represent a pattern of post-treatment relapse. The distinctive hypervascularity of this tumour histology may be observed in adenopathies and adrenal metastases. Second primary neoplasms should be considered in the differential diagnosis of lesions observed during follow-up.

Ultrasound of thyroid, parathyroid glands and neck lymph nodes.

In the past 15 years high-frequency B-mode sonography and colour-power Doppler have become the most important and most widely employed imaging modalities for the study of the neck, in particular for thyroid gland, parathyroids and lymph nodes. Sonography allows not only the detection but often also the characterization of the diseases of these organs, distinguishing benign from malignant lesions with high sensitivity and specificity, which could be further improved by the employ of ultrasound contrast agents and harmonic imaging. Although no single sonographic criterion is specific for benign or malignant nature of the lesions, the combination of different signs can be markedly helpful to speed up the diagnostic process. Fine-needle aspiration biopsy (FNAB) remains the most accurate modality for the definitive assessment of thyroid gland nodules and of any doubtful case of nodal disease. In association with clinical findings and serum levels of parathormone, FNAB has specificity close to 100% for the characterization of parathyroid adenomas. A combined approach with sonography and FNAB is generally highly effective.

Essential techniques for successful radio-frequency thermal ablation of malignant hepatic tumors.

Radio-frequency thermal ablation is one of the most promising minimally invasive techniques for the treatment of nonresectable hepatic tumors. Essential technical tips to successful radio-frequency ablation therapy were collected from five international experts. They were organized into five categories: understanding the mechanisms and principles of radio-frequency ablation, modulation of tissue physiologic characteristics to increase tumor destruction, strategies of overlapping ablations, strategies to improve ablation according to tumor location, and imaging strategies after ablation to ensure adequate therapy. Established factors for optimal ablation, as well as emerging technical tips, are addressed with illustrations in each section. These essential tips will be very helpful for physicians performing radio-frequency ablation of hepatic tumors.

[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)

Radiofrequency thermal ablation of hepatic metastases.

Percutaneous radiofrequency (RF) ablation is a promising therapeutic option for liver metastases, which may result in prolonged survival and chance for cure. Recent technological advancements provide larger coagulation volumes, allowing treatment of medium- and large-size metastases. Candidates are patients with metachronous liver metastases from colorectal or other primary cancers, in whom surgery is contraindicated and with one to four nodules each smaller than approx. 4 cm. We treated 109 patients with 172 colorectal metastases in the liver. Local control was obtained in 70.4% of lesions. Recurrence was significantly more frequent in lesions >3 cm. One major complication occurred (0.6% of sessions), a large bowel perforation requiring surgery. Seven minor complications did not require therapy. New metastases developed at follow-up in 50.4% of patients. Survival rates are 67% and 33% after 2 and 3 years, respectively; estimated median survival being 30 months. RF ablation advantages include minimal-invasiveness (no mortality, significantly lower complications), reduced costs and hospital stays compared to surgery, feasibility in non-surgical candidates, and the potential of repeated treatment if local recurrence occurs or new metastases develop.

Multiple myeloma index: verification of a new prognostic approach with evaluation of treatment response.

BACKGROUND AND OBJECTIVE: Currently adopted prognostic criteria for multiple myeloma (MM) still lack reliable predictive ability to select subsets of patients for different therapies, in particular for intensive treatment protocols. In this work we aimed to test the prognostic value of the MM Prognostic Index (MMPI), developed in 1996 by Grignani et al. from Pavia University as a clinical and investigational tool. DESIGN AND METHODS: Ninety-three MM patients were eligible for the study. All received initial induction therapy based on a standard 6-month melphalan + prednisone (M + P) protocol. Clinical and laboratory parameters, conventional staging and bone marrow infiltration percentage and cytopathology (BMIC) were assessed at diagnosis, while treatment response (TR) was evaluated using criteria after induction therapy. Cox's multivariate survival analysis was applied on prognostic data. RESULTS: In our patients independent prognostic value was confirmed for British Medical Research Council staging, BMIC and TR, the three factors considered in MMPI. Risk classes obtained via MMPI identify patients with different outcomes; moreover, the index discriminates significantly among Stage II patients. INTERPRETATION AND CONCLUSIONS: This new approach to MM prognosis is simple and reliable from the prognostic point of view; it refers not only to neoplastic mass, but also to intrinsic proliferative capacity of the malignant clone and to tumor-host interactions. We recommend its adoption in clinical practice and in the evaluation and design of therapeutic trials.

[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.

Verification and comparison of two different predictive equations in Hodgkin's disease.

BACKGROUND AND OBJECTIVE: In recent years, two predictive equations to estimate median expected survival at diagnosis for patients affected with Hodgkin's disease have been developed at the University of Pavia Medical School. The present retrospective work was aimed at testing correlation between mean survival estimated using the two equations and observed survival, and at comparing the results of the two different equations. METHODS: Fifty-three deceased patients were considered from a series of 114 consecutive ones. All these patients had been treated in a conventional way according to therapeutic modalities similar to those used in the series from which the two equations were derived. Expected median survival values calculated with the older, linear equation and with the newer exponential one were compared with observed survival. RESULTS: Mean survival of the whole series was over 24 years, with survival probabilities of 85% after 5 years and 74% after 10 years. Using the first predictive equation on the 53 deceased patients resulted in a satisfactory correlation between estimated median survival and real survival: Pearson's R correlation coefficient value is 0.5996, with a t value of 5.35 and p < 0.001. The more recent exponential predictive equation showed a better correlation between estimated median survival and observed survival: R = 0.7338, t = 7.71, p < 0.001. INTERPRETATION AND CONCLUSIONS: The new exponential equation, while apparently complex, is superior to the older one, and is a very reliable and straightforward tool for estimating median expected survival: its forecast proves to be an important pretreatment parameter in every HD patient. These observations support widespread use of this tool in clinical practice to evaluate the prognosis of Hodgkin patients in a more accurate and flexible way.