[General adverse reactions to contrast agents. Classification and general concepts]. / Reacciones adversas generales a los contrastes. Clasificación y conceptos generales.

General adverse reactions to intravenous contrast agents are uncommon, although relevant due to the growing number of radiologic tests that use iodinated or gadolinium-based contrast agents. Although most of these reactions are mild, some patients can experience significant reactions that radiologists should know how to prevent and treat.

Reacciones adversas generales a los contrastes. Clasificación y conceptos generales / General adverse reactions to contrast agents. Classification and general concepts

Las reacciones adversas generales a los medios de contraste de administración intravenosa son una entidad infrecuente, aunque relevante debido al número cada vez mayor de exploraciones radiológicas que emplean medios de contraste yodados o de gadolinio. Aunque en su mayor parte son de carácter leve, algunos pacientes pueden tener efectos considerables que el radiólogo debe saber prevenir y eventualmente tratar (AU)

General adverse reactions to intravenous contrast agents are uncommon, although relevant due to the growing number of radiologic tests that use iodinated or gadolinium-based contrast agents. Although most of these reactions are mild, some patients can experience significant reactions that radiologists should know how to prevent and treat (AU)

Manejo inicial del ictus isquémico agudo / No disponible

No disponible

[Noninvasive diagnosis of cerebral venous thrombosis]. / Diagnóstico de trombosis venosas cerebrales mediante técnicas no invasivas.

OBJECTIVES: Cerebral venous thrombosis (CVT) is an uncommon condition. Its variable, unspecific clinical presentation causes delays in diagnosis. We analyze the validity of different neuroimaging techniques, including CT, MRI, MR angiography, and conventional angiography in the diagnosis of CVT. MATERIAL AND METHODS: We review the imaging findings of 12 patients with the final diagnosis of CVT. All 12 patients underwent CT as the initial imaging test; all 12 underwent MRI; 11 underwent MR angiography; and 4 underwent conventional angiography. Visualization of the thrombus or filling defects in the affected vessel were considered direct signs of CVT, whereas findings compatible with venous infarction were considered indirect signs. RESULTS: Of the 12 CT examinations, 4 showed direct signs, 2 indirect signs, and 6 only normal findings. Indirect signs of CVT were seen on follow-up CT in three of the patients with normal initial CT examination. CT failed to show the real extent of the process except in one case in which a cortical vein was affected. MRI detected thrombi in the affected territory in 6 cases; the empty delta sign was seen in 2 and signs of venous infarction in 8. MRI failed to diagnose CVT in one case. MR angiography showed direct signs of CVT in all cases, even without intravenous contrast, and the results were similar to those seen at conventional angiography. More than two locations were affected in 11 patients. CONCLUSIONS: At CT, indirect signs of CVT are seen, although sometimes not immediately. Direct signs can be so subtle that they can only be interpreted with experience. Furthermore, CT does not show the real extent of the process. Nevertheless, given its availability, contrast-enhanced CT should be the primary imaging test, both to rule out other possibilities and to indicate other neuroimaging studies, in this case MRI and MR angiography. The results obtained when these two techniques are performed simultaneously, even without contrast administration, are sufficient for diagnosis and are comparable to those at conventional angiography, but without the risks entailed and without exposing the patient to ionizing radiation.

Diagnóstico de trombosis venosas cerebrales mediante técnicas no invasivas / Noninvasive diagnosis of cerebral venous thrombosis

Objetivos. La trombosis venosa cerebral (TVC) es una patología poco frecuente. Su presentación clínica es inespecífica y variable, lo que ocasiona retrasos en el diagnóstico. Analizamos la validez de las diferentes pruebas de neuroimagen, tomografía computarizada (TC), resonancia magnética (RM), angio-resonancia magnética (RMV) y angiografía, en el diagnóstico de TVC. Material y métodos. Estudio retrospectivo sobre 12 pacientes con diagnóstico final de TVC. Se realizó TC, que fue la prueba inicial, y RM a todos los pacientes, a 11 RMV y en 4 ocasiones se hizo angiografía. Se valoraron como signos directos la visualización del trombo o defectos de repleción en el vaso afecto y como signo indirecto la identificación de hallazgos compatibles con infarto venoso. Resultados. De las 12 TC, 4 mostraron signos directos, 2 indirectos y 6 fueron normales; de éstas, en 3 pacientes se objetivaron signos indirectos en TC evolutivos. No mostró la extensión real del proceso salvo en un caso de afectación localizada de una vena cortical. En la RM se objetivó ocupación de los vasos del territorio venosos afecto en 6 casos, en 2 se apreció el signo del delta vacío y en 8 signos de infarto venoso. En una ocasión no fue diagnóstica. En todas las RMV se visualizaron signos directos de TVC, incluso sin contraste intravenoso. Los resultados fueron similares a los de las angiografías. Once pacientes presentaban afectación de más de 2 localizaciones. Conclusiones. La TC pone de manifiesto signos indirectos, a veces de modo tardío, y signos directos tan sutiles que requieren experiencia para ser interpretados. Además no valora la extensión real del proceso. De todos modos debe utilizarse como técnica de primer nivel, con contraste intravenoso, dada su disponibilidad en la mayoría de los centros, para excluir otras causas y servir para la indicación de otras pruebas de neuroimagen, en este caso RM y RMV. Los resultados obtenidos con la realización simultánea de ambas son equiparables a los de la angiografía, evita los riesgos de esta técnica, no expone al paciente a radiaciones ionizantes y es diagnóstica incluso sin la administración de contraste

Objectives. Cerebral venous thrombosis (CVT) is an uncommon condition. Its variable, unspecific clinical presentation causes delays in diagnosis. We analyze the validity of different neuroimaging techniques, including CT, MRI, MR angiography, and conventional angiography in the diagnosis of CVT. Material and methods. We review the imaging findings of 12 patients with the final diagnosis of CVT. All 12 patients underwent CT as the initial imaging test; all 12 underwent MRI; 11 underwent MR angiography; and 4 underwent conventional angiography. Visualization of the thrombus or filling defects in the affected vessel were considered direct signs of CVT, whereas findings compatible with venous infarction were considered indirect signs. Results. Of the 12 CT examinations, 4 showed direct signs, 2 indirect signs, and 6 only normal findings. Indirect signs of CVT were seen on follow-up CT in three of the patients with normal initial CT examination. CT failed to show the real extent of the process except in one case in which a cortical vein was affected. MRI detected thrombi in the affected territory in 6 cases; the empty delta sign was seen in 2 and signs of venous infarction in 8. MRI failed to diagnose CVT in one case. MR angiography showed direct signs of CVT in all cases, even without intravenous contrast, and the results were similar to those seen at conventional angiography. More than two locations were affected in 11 patients. Conclusions. At CT, indirect signs of CVT are seen, although sometimes not immediately. Direct signs can be so subtle that they can only be interpreted with experience. Furthermore, CT does not show the real extent of the process. Nevertheless, given its availability, contrast-enhanced CT should be the primary imaging test, both to rule out other possibilities and to indicate other neuroimaging studies, in this case MRI and MR angiography. The results obtained when these two techniques are performed simultaneously, even without contrast administration, are sufficient for diagnosis and are comparable to those at conventional angiography, but without the risks entailed and without exposing the patient to ionizing radiation

Prestroke dementia.

OBJECTIVE: To determine the frequency, associated factors and outcome of dementia previous to a stroke. DESIGN: Cross-sectional study of a cohort of 324 consecutive unselected stroke patients (mean age 70.9 years, range 20-98; 255 ischaemic, 46 haemorrhagic and 25 indefinite). METHODS: Cognitive and functional status prior to stroke were assessed by means of an interview to a relative, a short version of the Informant Questionnaire on Cognitive Decline in the Elderly and the Barthel Index. The DSM-III-R criteria were used to establish the diagnosis of prestroke dementia. Clinical and CT features of patients with and without prestroke dementia were compared. RESULTS: Forty-nine patients (15%) were demented before stroke; they were significantly older, less well educated, they had more frequently female gender, prior cerebrovascular disease, cerebral and medial temporal lobe atrophy and leukoaraiosis in the CT scan, and they had a higher mortality rate. Female sex (OR 3.7, CI 95% 1.2-12), low education (OR 2.1, CI 95% 1.1-4.2), previous stroke (OR 3.6, CI 95% 1.2-11), and cerebral atrophy (OR 3.8, CI 95% 1.7-8.3) were independently associated with prestroke dementia in the logistic regression analysis. CONCLUSIONS: Fifteen percent of stroke patients have prestroke dementia and they have a worse outcome. Factors associated with prestroke dementia are reminiscent both of degenerative and vascular brain pathology.

Phyllodes tumors of the breast.

The aim of this study was to describe the clinical, mammographic, and sonographic findings of phyllodes tumor of the breast and correlate them to the benign or malignant pathological nature of the lesion and its clinical behavior. We retrospectively reviewed the clinical, radiologic, and pathologic findings of 12 cases of phyllodes tumors diagnosed in our hospital in the past 6 years, 6 of which were malignant. The surgical management and clinical course of the patients were also reviewed. Mammographically, soft tissue masses ranging from 2.5 to 15 cm were present in all patients. One patient had a mixed fat and water density mass and 2 patients had masses associated with coarse calcifications. At sonography, all tumors were well circumscribed; two of them were homogeneously hypoechoic, and the rest had heterogeneous internal echoes. Eight patients showed internal cystic areas. None of these characteristics proved to be useful in ascertaining the benign or malignant nature of the tumor. At surgery, 5 patients underwent mastectomy and 7 patients local excision of the tumor. Three of the later tumors, one benign and two malignant, recurred after several months. Fine-needle aspiration biopsy suggested the diagnosis of phyllodes tumor in only 3 cases. After surgery, six tumors were classified as benign and six as malignant, three of which being of low-grade malignancy. None of the clinical or radiologic characteristics of the tumors were useful in predicting their histological nature or their behavior after surgery. Preoperative fine-needle aspiration biopsy often misdiagnosed the tumor as benign fibroadenoma. Only the histopathologic features of the excised mass proved to be helpful in assessing malignancy.

Imaging findings in renal hydatid disease.

The aim of this work is to describe the image findings of renal hydatid disease, especially on MR. Four cases of echinococcal involvement of the kidney were retrospectively reviewed. All patients had intravenous urography (IVU) and US performed. Computed tomography examination was available in three patients and MR in two cases. Intravenous urography demonstrated communication of the cyst to the collecting system in one case. Ultrasound revealed multicystic appearance in three cases and unilocular in one case. Computed tomography demonstrated unilocular thick-walled or multilocular cysts with well-defined walls, calcified in one case. In multilocular cysts the CT densities of the fluid of daughter cysts was significantly lower than the fluid of mother cysts. This typical appearance was present in three of our cases. The presence of a hypointense rim and a multicystic appearance were distinctive in MR imaging. The combined findings of these different imaging modalities aid greatly in establishing the correct diagnosis. Magnetic resonance imaging is of value in determining the presence of a characteristic rim and enables the evaluation of anatomical relationships.

Transrectal ultrasonography in the diagnosis of urethral diverticula in women.

The diagnosis of urethral diverticula in women can be difficult. Several imaging modalities have been described for evaluating this entity: urethrography; transabdominal, transrectal, transvaginal, and transperineal ultrasonography; computed tomography (CT); and magnetic resonance (MR) can be helpful in evaluating a diverticulum and its relationship to the urethra. We report on four women aged 36 to 42 years with urethral diverticula. Transrectal ultrasonography (TRU) was the most useful diagnostic test in our series. TRU showed 7 urethral diverticula and provided information about its shape, volume, and content as well as its spatial relationship about its shape, volume, and content as well as its spatial relationship to the urethra. In two cases, multiple diverticula were detected when only a single lesion was clinically suspected. Transabdominal sonography failed to demonstrate small diverticula. CT examination did not provide additional information except for the passage of the contrast from the urethra to the diverticulum in one of the cases. Voiding cystourethrogram was positive in only one patient.

Calcified amyloidoma of the larynx.

We describe a case of laryngeal amyloidoma in a 39-year-old man in whom CT examination disclosed a calcifield soft-tissue mass arising in the epiglottis. The presence of focal calcifications suggested a cartilaginous tumor.

Abdominal cystic lymphangiomas: US and CT findings.

We retrospectively analyzed six cases of abdominal cystic lymphangiomas (CL), who had undergone surgical resection. These cases had been evaluated by several modalities: ultrasonography (US), computed tomography (CT), angiography and fine needle aspiration. No age predilection was found. All patients were symptomatic. The most common presenting symptoms were abdominal pain (66%), palpable mass (66%), fever (50%) and vomiting (30%). US showed septations (85%) and unicameral mass (15%); in three cases (50%) echogenic material within the cyst was found, probably due to hemorrhage and infection. CT showed capsular enhancement in all cases. Capsular and septation thickness were slightly increased in cases of infection or bleeding. At CT the contents were usually of fluid attenuation (66%); in 33% the attenuation values were higher, probably because of internal bleeding and infection. US was superior to CT in the demonstration of septations and the internal nature of the cysts. The major role of imaging is to demonstrate the cystic nature of these abdominal masses, because they do not have specific signs or symptoms that could allow a clinical diagnosis.

Real-time ultrasound evaluation of tuberculous pleural effusions.

An evaluation of 21 patients with tuberculous pleurisy was carried out to assess the role of ultrasonography in the diagnosis of tuberculous pleural effusion. Ultrasonography revealed winding structures of different lengths and thicknesses (winding bands) in 8 patients, and filiform structures of a higher echogenicity and a shorter length (linear echoes) in 13. These findings were associated with exudates having a high content of fibrin and protein, respectively, suggesting that winding bands might be formed by fibrin and linear echoes by protein macroaggregates. Based upon these observations, ultrasonography seems to be a useful method for identifying tuberculous pleural effusion.