The legal implications of error in radiology.

Evaluation of the legal implications of error in radiology and therefore the assessment of criminal and civil liability in the practice of the profession requires an analysis of how the public perception of the right to health has radically changed. This change has initiated a defensive approach to medicine and radiology that tends to be oriented towards precautionary measures, with a proliferation of often unnecessary imaging studies. In radiology, errors of omission or commission are frequent. A critical appraisal of the different types of error in radiology will help practitioners undertake the essential corrective measures. Through analysis of several cases derived from legal or insurance proceedings brought against radiologists, the most common forms of error are described, and their implications for criminal and civil liability are illustrated, although it is emphasised that the existence of an error does not always translate into the presence of malpractice.

Multislice CT in emergency room management of patients with chest pain and medium-low probability of acute coronary syndrome.

PURPOSE: The main cause of acute chest pain, which accounts for 6.5% of urgent medical examinations in emergency rooms in Italy, is acute coronary syndrome (ACS). We performed this prospective study to evaluate the diagnostic accuracy of a 16-channel computed tomography (CT) scanner with dedicated software in a group of patients with chest pain and medium to low risk of ACS. MATERIALS AND METHODS: This study involved a selected group of 31 patients reporting chest pain with a medium to low probability of ACS, defined on the basis of preliminary tests [electrocardiogram (ECG) and serum cardiac markers]. Coronary angiography, performed within 24 h of MSCT, was used as the gold standard. RESULTS: MSCT identified the presence of occlusions and significant (>50%) or nonsignificant stenoses in the main coronary segments, with a sensitivity of 65%, a specificity of 98.8%, a positive predictive value (PPV) of 81.2%, a negative predictive value (NPV) of 97.3% and an accuracy of 96.4%. Significant stenoses and occlusions were detected with a sensitivity of 71.4%, a specificity of 99.6%, a PPV of 93.7%, an NPV of 97.7% and an accuracy of 97.5%. CONCLUSIONS: Due to its high NPV, this technique can rule out significant stenoses or coronary occlusions provided that image quality is excellent. In patients with a medium to low coronary risk, MSCT is a more accurate indicator of the need for coronary angiography than is exercise stress testing, which is less expensive but has lower predictive values.

Atherosclerotic renovascular disease: medical therapy versus medical therapy plus renal artery stenting in preventing renal failure progression: the rationale and study design of a prospective, multicenter and randomized trial (NITER).

BACKGROUND: Many studies suggest a major prevalence of atherosclerotic renovascular disease (ARVD), caused by mono or bilateral renal artery stenosis (RAS). Unfortunately, there is no definite therapy to cure this disease to date; therefore, ARVD is burdened by important clinical complications with high social and economic costs. The last few years have seen important advancements in both medical therapy and in interventional radiology (for example, percutaneous transluminal renal artery stenting (PTRS)). All of them could affect, in some way, the natural history of ARVD, but to date the optimal strategy has not been established. METHODS: The protocol of a prospective, multicenter, randomized trial "Nephropathy Ischemic Therapy (NITER)" is presented. It enrolls patients with stable renal failure (glomerular filtration rate (GFR) >or=30 ml/min) and hypertension, and hemodynamically significant atherosclerotic ostial RAS (>or=70%) diagnosed by duplex Doppler (DD) ultrasonography and confirmed by magnetic resonance angiography (MRA). This study aims to evaluate whether medical therapy plus interventional PTRS is superior to medical therapy alone according to the following combined primary endpoint: death or dialysis initiation or reduction by >20% in estimated GFR after 0.5, 1, and 2 yrs of follow-up and an extended follow-up until the 4th year. Medical therapy means drugs to control hypertension, improve dyslipidemia and optimize platelet anti-aggregant therapy. The sample size is estimated in 50 patients per group to achieve a statistical significance of 0.05 in case of a reduction by 50% in the combined endpoints.

Spinal intradural extramedullary haemangioma: MRI and neurosurgical findings.

Haemangiomas, have rarely been encountered in the spinal intradural extramedullary space and the MRI findings of this entity have been described only in a few cases. We present the Magnetic Resonance Imaging (MRI) and surgical findings of a rare case of intradural extramedullary cavernous angioma located at the T1-T2 level in a 65-year-old man presented progressive paraparesis and upper thoracic back pain. On MRI, a well-circumscribed intradural solid mass, 1 cm in diameter, was detected and another enhancing nodular mass was found at the nerve roots of the cauda equina. The thoracic spinal lesion was removed and the histological diagnosis confirmed cavernous haemangioma. Although very uncommon, haemangioma should be included in the differential diagnosis when a spinal intradural extramedullary lesion is discovered and some neuroradiological findings could allow a presumptive diagnosis.

Focal nodular hyperplasia: morphologic and functional information from MR imaging with gadobenate dimeglumine.

PURPOSE: To determine whether gadobenate dimeglumine (Gd-BOPTA) is able to provide morphologic and functional information for characterization of focal nodular hyperplasia (FNH). MATERIALS AND METHODS: Sixty-three consecutive patients with proved FNH were retrospectively examined. Magnetic resonance (MR) imaging with T2-weighted turbo spin-echo and T1-weighted gradient-echo sequences was performed. Images were acquired prior to and during the dynamic phase of contrast-material enhancement and 1-3 hours after administration of 0.1 mmol/kg Gd-BOPTA. Qualitative analysis of signal intensity and homogeneity on images in the various phases of the MR study and examination for the presence of central scar or atypical features were performed. On the basis of features observed in the precontrast and dynamic phases, lesions were defined as typical or atypical. Intensity and enhancement patterns of the lesions and scars were also evaluated in the delayed phase. RESULTS: One hundred FNHs were depicted on MR images. Seventy-nine of 100 lesions demonstrated typical morphologic and enhancement characteristics. On delayed phase images, 72% of 100 FNHs appeared hyperintense; 21%, isointense; and 7%, slightly hypointense. The delayed pattern of enhancement was homogeneous, heterogeneous, and peripheral in 58%, 22%, and 20% of 100 FNHs, respectively. Atypical morphologic features and lesion and/or scar enhancement were observed in 21 of 100 FNHs. On delayed phase images, 76% of 100 atypical FNHs appeared hyperintense, 14% isointense, and 10% slightly hypointense. Hyperintensity and isointensity allowed the correct characterization in 90% of atypical FNHs. CONCLUSION: Gd-BOPTA during both dynamic and delayed phases provides morphologic and functional information for the characterization of FNH.

Hepatic adenomas: imaging and pathologic findings.

Hepatocellular adenoma is a rare benign lesion that is most often seen in young women with a history of oral contraceptive use. It is typically solitary, although multiple lesions have been reported, particularly in patients with glycogen storage disease and liver adenomatosis. Because of the risk of hemorrhage and malignant transformation, hepatocellular adenomas must be identified and treated promptly. At pathologic analysis, hepatocellular adenoma is usually a well-circumscribed, nonlobulated lesion, and at gross examination, resected adenomas frequently demonstrate areas of hemorrhage and infarction. Most adenomas are not specifically diagnosed at ultrasonography (US) and are usually further evaluated with computed tomography (CT) or other imaging modalities. Color Doppler US may help differentiate hepatocellular adenoma from focal nodular hyperplasia. Multiphasic helical CT allows more accurate detection and characterization of focal hepatic lesions. Hepatocellular adenomas are typically bright on T1-weighted magnetic resonance images and predominantly hyperintense relative to liver on T2-weighted images. The prognosis of hepatic adenoma is not well established. Criteria that guide treatment include the number and size of the lesions, the presence of symptoms, and the surgical risk incurred by the patient. Understanding the imaging appearance of hepatocellular adenoma can help avoid misdiagnosis and facilitate prompt, effective treatment.

Accuracy of mammography and echography versus clinical palpation in the assessment of response to primary chemotherapy in breast cancer patients with operable disease.

The response to primary chemotherapy is an important prognostic factor in patients with non metastatic breast cancer. In this study we compared the assessment of response performed by clinical palpation to that performed by echography and mammography in 141 out of 157 consecutive breast cancer patients (T2-4, N0-1, M0) submitted to primary chemotherapy. A low relationship was recorded between tumor size assessed clinically and that evaluated by either mammography: Spearman R = 0.38 or echography: R = 0.24, while a greater correlation was found between the tumor dimension obtained by the two imaging techniques (R = 0.62). According to the WHO criteria, the grade of response of breast cancer to primary chemotherapy, showed by mammography and echography, was less marked than the grade of response seen at clinical examination. Residual tumor size assessed clinically depicted a stronger correlation with pathological findings (R = 0.68) than the residual disease assessed by echography (R = 0.29) and mammography (R = 0.33). Post-chemotherapy histology evaluation revealed pathological complete response in three cases (2.1%). Two of these cases were judged as complete responders by clinical palpation but only one was recognized by mammography, and none by echography. Clinical response, but not the response obtained by the two imaging techniques, was a significant predictor for longer disease free survival (p = 0.04). To conclude, physical examination measurements remain the method of choice in evaluating preoperatively the disease response in trials of primary chemotherapy. Prediction of pathological outcome is not improved by echography and mammography.

Congenital absence of portal vein with nodular regenerative hyperplasia of the liver.

Congenital absence of the portal vein is a very rare anomaly. The intestinal and splenic venous drainage bypasses the liver and drain into the inferior vena cava (IVC). Two cases of such anomaly are described. Both cases were investigated by US coupled with echo-colour Doppler examination, CT and MR imaging, followed by digital subtraction angiography (DSA) and liver biopsy. In the first case the splenic and superior mesenteric vein formed a venous trunk which emptied directly into the IVC; in the second case, the splanchnic blood flowed into a dilated hepatofugal inferior mesenteric vein which connected to the left internal iliac vein. In both cases nodular regenerative hyperplasia of the liver was present, presumably due to an abnormal hepatic cell response to the absent portal flow. The particular contribution of MR imaging to the diagnosis of both vascular abnormalities and liver parenchyma derangement and its advantages over the other diagnostic techniques is emphasized. The clinical and radiological features of 17 previously reported cases are reviewed.

The pseudocapsule in hepatocellular carcinoma: correlation between dynamic MR imaging and pathology.

Nodular hepatocellular carcinoma (HCC) is characterized by the presence of a pseudocapsule (constructed usually from connective fibrous tissue) that appears hypointense on T1- and T2-weighted spin-echo (SE) and gradient-echo (GE) MR imaging sequences without a contrast medium. The presence of vascular structures inside the tumor, which are verified by histological exam, affects enhancement of the PC after administrating the contrast medium: The impregnation is more evident in the dynamic study but also persists on the delayed T1-weighted SE images. The accuracy of MR in detecting the pseudocapsule of HCC and contrast enhancement of the pseudocapsule during dynamic studies were evaluated and related to pathological findings. Thirty-seven HCC were examined in 33 patients and afterwards resected. In capsulated nodules, besides usual hematoxylin, eosin, and trichrome stainings, histochemical and immunohistochemical methods were performed. On a 1.5-T MR unit, T1- and T2-weighted SE and GE FLASH 2D sequences after intravenous injection of Gd-DTPA (dynamic study) were used. In a later phase, T1-weighted SE sequences were repeated. Histologically, the pseudocapsule (thickness 0.2-6 mm) was present in 26 of 37 nodules (70%). The dynamic study was the most suitable technique to show the pseudocapsule, which was recognized in 80.7% (21 of 26 nodules). In 5 of 26 cases, the pseudocapsule, not demonstrated by MR, was thinner than 0.4 mm. In 16 of 21 cases, in the early portal phase (30-60 s), the pseudocapsule had an early enhancement, which was more evident later; in 5 of 21 cases the enhancement was observed only in the late portal phase (1-2 min). At histological examination, 14 of 16 pseudocapsules with early enhancement showed a more prominent vasculature than those with enhancement in the equilibrium phase. Magnetic resonance was a reliable tool in demonstrating the pseudocapsule of HCC. The histological examination demonstrated a good correlation between the enhancement behavior and the vessel number of the pseudocapsule.

[Is mammography useful in the detection of breast cancer in women 35 years of age or younger?]. / E utile la mammografia nel cancro della mammella nelle donne con età pari o inferiore a 35 anni?

Breast cancer in women 35 years old or younger is unusual. It accounts for 1-3.6% of all breast cancers but is the leading cause of cancer mortality in women 15-35 years old. The diagnostic delay, with T2 or more advanced cancer at clinical presentation, is due to the patient's age and the opinion of low mammographic reliability for cancer diagnosis in this age group. To assess the usefulness of mammography in breast cancer patients aged 35 years or younger, we reviewed the clinical, mammographic and histologic data of 65 cancers collected in 7 breast diagnosis and counseling centers in Lombardy. Fifty-three patients (81.5%) were referred for a palpable breast mass, which was a T2 or more advanced cancer in 23 cases. Mammography showed malignant patterns (spiculated opacities, clusters of microcalcifications, casting, branching and ductal type calcifications) in 31 patients (47.7%). Mammography was not definitive but correctly suggested further examinations in 30 women and it had only 4 false negatives. Ultrasonography performed in 43 patients was negative in 3 (7%), pathologic and pathognomonic for cancer in 27 (62.8%) and pathologic but not indicative of malignancy in 13 (20.2%). The cytologic or histologic diagnosis of breast cancer was made under US guidance in 24 cases. In women aged 35 years or younger mammography was effective in identifying breast cancers; US and fine-needle aspiration biopsy (FNAB) complete mammography. We believe that mammography can be a valuable screening tool in young women at high risk for breast cancer because of family history.

[Magnetic resonance angiography with TOF-TONE tridimensional sequences in the study of steno-occlusive diseases of the renal arteries. Comparison with digital angiography]. / Angiografia con Risonanza Magnetica con sequenze tridimensionali TOF-TONE nello studio delle malattie steno-occlusive delle arterie renali. Confronto con angiografia digitale.

The authors examined 32 patients (68 renal arteries in all) with suspected renovascular hypertension with MRA (3D TOF-TONE sequences) and DSA. MRA visualization of the renal vessels was considered good in 96.8%, 91.6%, 76.6% and 16.6% of cases for the ostium, the proximal third, the distal third and the hilum, respectively. MRA correctly assessed the 4 occlusions in our series and 19/20 atherosclerotic stenoses, all in proximal site. In proximal stenosis detection, MRA had 100% sensitivity and 98% specificity in atherosclerotic sclerosis-occlusion grading considering a 50% caliber reduction as the cut-off value. The two techniques were in agreement in 68% of cases; MRA overestimated stenosis grade in 25% of cases. The 3D TOF-TONE sequence is a reliable diagnostic tool in the study of the proximal tract of the renal arteries, but its major limitation remains in distal tract studies. Nevertheless, this technique has elective indications in a selected group of patients, namely the elderly with hypertension and impaired renal function.

[Malignant mesothelioma of the pleura: correlations between thoracoscopy and radiology]. / Mesoteliomi maligni della pleura: correlazioni tra toracoscopia e radiologia.

The frequency of malignant pleural mesothelioma has increased greatly in the past three decades; it is a tumor of great clinical, epidemiologic and therapeutical interest. Therapy should not be started before the tumor has been correctly diagnosed and staged with thoracoscopy and computed tomography (CT) which have replaced plain chest radiography. To help optimize the combination of these techniques, the authors report on their experience in 37 patients examined with conventional radiology and then with thoracoscopy. In 26 patients with CT findings of malignant pleural mesothelioma, the authors compared thoracoscopy and CT findings in the assessment of neoplastic spread to the parietal (stage IA) and/or visceral (stage IB) pleura. CT appears to be the technique of choice after plain chest radiography: if the suspected malignant pleural mesothelioma is classified as stage II, III or IV, thoracoscopy should be used only for histologic confirmation. Conversely, in stages IA and IB, thoracoscopy--besides histology--should be used to confirm malignant spread to the visceral pleura.

[The role of magnetic resonance angiography in the assessment of arterial stenosis in the transplanted kidney]. / Ruolo dell'angiografia con Risonanza Magnetica nella valutazione delle stenosi dell'arteria del rene trapiantato.

Artery stenosis in the transplanted kidney is the most frequent vascular complication; hypertension onset or worsening may be associated and, at an end stage, also renal insufficiency. The diagnosis must be early and accurate and provide guidelines for medical, interventional or surgical therapy. To assess the diagnostic reliability or MRA, 27 patients were examined. On the basis of clinical, biochemical, pharmacological (Captopril test) and instrumental (color-Doppler US) examinations, the artery of the transplanted kidney was considered normal in 6 patients and stenotic in 21. In the control group, MRA results were in agreement with color-Doppler findings. On the contrary, in 8 of 21 abnormal conditions, the two techniques were in disagreement. Digital angiography, considered as the gold standard, was performed in any questionable case, confirming a slight overestimation of the stenoses by MRA (3 cases) and 2 false positives by color-Doppler US. The authors believe color-Doppler US to be a reliable technique for screening stenosed arteries in the transplanted kidney. MRA is proposed as a complementary investigation useful to define stenosis type and to provide guidelines for treatment.

[Do clinical or physiopathological parameters exist for rationalizing the demand for thoracic radiograms in patients admitted to an intensive care unit]. / Esistono parametri clinici o fisiopatologici per razionalizzare la richiesta di radiogrammi del torace nei pazienti ricoverati in un centro di rianimazione?

To rationalize the demand of chest radiography in Intensive Care Unit patients, 423 radiographs of 35 patients were studied prospectively. The radiologic findings were compared with clinical data, blood gas analysis and laboratory data. No significant correlation was demonstrated between pulmonary radiographic changes and patient clinical conditions classified as unchanged, improving and worsening. In contrast, a good correlation (R = 0.65; p < 0.001) was observed between the chest radiographic score of pulmonary changes and the PaO2/FiO2 ratio. Changes in this parameter may be a good reason to perform bedside chest radiographs, whereas this exam appears rather useless when PaO2/FiO2 ratio is unchanged.

[Comparison of ultrasonography, computerized tomography, and magnetic resonance in the study of parotid masses]. / Ecotomografia, tomografia computerizzata e risonanza magnetica a confronto nello studio delle lesioni espansive della parotide.

One hundred and seven patients were examined to compare advantages and pitfalls of the imaging methods currently used to stage parotid masses. Thirty patients underwent US and CT, 44 were investigated with US and MRI and 33 with US, CT and MRI. The accuracy of the three techniques was analyzed in detecting and assessing the intra-/extraglandular location of the parotid lesions and their benign/malignant nature. The intraglandular lesion spread to superficial/deep lobes was also investigated, together with its relationship to the surrounding structures. The findings were correlated with the cytohistological data from US-guided biopsy or from surgical resection. US was less accurate than CT and MRI, the latter being not statistically superior to the former. Because of the low incidence of pitfalls, US with fine-needle aspiration cytology should be the technique of choice; CT and MRI must be used for lesions > 3 cm or for masses in the deep gland lobes. In conclusion, CT accurately assesses parotid lesions but MRI demonstrates the relationship to adjacent structures better.

[Anatomo-radiologic definition of minimal interstitial silicosis and diagnostic contribution of high-resolution computerized tomography]. / Definizione anatomo-radiologica della silicosi minima interstiziale e contributo diagnostico della tomografia computerizzata con alta risoluzione.

Minimal interstitial silicosis (MIS) is a histologic entity characterized by questionable radiologic findings--i.e., the p/p 0/1 and 1/0 classes of the International Labour Office (ILO) 1980 classification. Thus, the condition may be responsible for borderline radiologic findings ("suspect" phase of pneumoconiosis). In order to test an alternative method to conventional radiology (CR), HRCT was performed on 35 workers exposed to silica and with histologic diagnosis of MIS: HRCT scans were compared with posteroanterior chest radiographs by using the ILO classification. Histology was the gold standard. HRCT identified many more MIS lesions. Moreover, the superiority of HRCT over CR was also proved by its better correlation with pathologic findings. HRCT provided pieces of information which could not always be obtained by means of conventional chest films. Thus, HRCT can be considered the method of choice in MIS before transbronchial lung biopsy.