Tomografía computada de alta resolución en el diagnóstico de la fibrosis pulmonar idiopática / High resolution computed tomography in the diagnosis of idiopathic pulmonary fibrosis

El patrón de neumonía intersticial usual (NIU) en la tomografía computada de alta resolución (TCAR) tiene un alto grado de correlación con el patrón histológico lo que permite obviar en dichos casos la necesidad de realizar biopsia pulmonar. La exactitud del diagnóstico de NIU en TCAR se basa en la detección de signos específicos de fibrosis como el panal y las densidades reticulares con bronquiolectasias por tracción. La actualización de las guías 2018 de práctica clínica de la ATS/ERS/JRS/ALAT de Fibrosis Pulmonar Idiopática (FPI) y la declaración de consenso de la Sociedad Fleischner proponen una nueva forma de clasificar los patrones tomográficos tomando en cuenta los aspectos antes considerados. Si bien la presencia de panal sigue siendo el hallazgo principal para caracterizar el patrón NIU, la distribución del reticulado intersticial y la presencia de bronquiolectasias por tracción en el contexto clínico especifico puede ser suficiente para realizar el diagnóstico de fibrosis pulmonar idiopática.

Usual interstitial pneumonia pattern (UIP) in high-resolution computed tomography (HRCT) has a high degree of correlation with the histological pattern which makes it possible to obviate in these cases the need for lung biopsy. The accuracy of a UIP diagnosis in HRCT is based on the detection of specific signs of fibrosis such as honeycomb and reticular densities with traction bronchiolectasis. The update of the 2018 Clinical Practice Guidelines of the ATS / ERS / JRS / ALAT of Idiopathic Pulmonary Fibrosis (IPF) and the Fleischner Society White Paper proposed a new way of classifying the tomographic patterns taking into account the aspects previously considered. Although the presence of honeycomb remains the main finding to characterize the UIP pattern, the distribution of interstitial reticulate and the presence of traction bronchiolectasis, in the specific clinical context, may be sufficient to make the diagnosis of idiopathic pulmonary fibrosis.

[Early detection of lung cancer using computed tomography among patients with chronic obstructive pulmonary disease]. / Detección precoz de cáncer pulmonar con tomografía computarizada de tórax en pacientes con enfermedad pulmonar obstructiva crónica tabáquica.

BACKGROUND: Chest computed tomography (CT) scan may improve lung cancer detection at early stages in high risk populations. AIM: To assess the diagnostic performance of chest CT in early lung cancer detection in patients with chronic obstructive pulmonary disease (COPD). PATIENTS AND METHODS: One hundred sixty one patients aged 50 to 80 years, active or former smokers of 15 or more pack-years and with COPD were enrolled. They underwent annual respiratory functional assessment and chest computed tomography for three years and were followed for five years. RESULTS: Chest CT allowed the detection of lung cancer in nine patients (diagnostic yield: 5.6%). Three cases were detected in the initial CT and six cases in follow-up scans. Most patients were in early stages of the disease (6 stage Ia and 1 stage Ib). Two patients were diagnosed at advanced stages of the disease and died due to complications of cancer. Two thirds of patients had nonspecific pulmonary nodules on the initial chest CT scan (100 patients, 62%). Seventy four percent had less than three nodules and were of less than 5 mm of diameter in 57%. In 92% of cases, these were false positive findings. In the follow-up chest CT, lung nodules were detected in two thirds of patients and 94% of cases corresponded to false positive findings. CONCLUSIONS: Chest CT scans may detect lung cancer at earlier stages in COPD patients.

Detección precoz de cáncer pulmonar con tomografía computarizada de tórax en pacientes con enfermedad pulmonar obstructiva crónica tabáquica / Early detection of lung cancer using computed tomography among patients with chronic obstructive pulmonary disease

Background: Chest computed tomography (CT) scan may improve lung cancer detection at early stages in high risk populations. Aim: To assess the diagnostic performance of chest CT in early lung cancer detection in patients with chronic obstructive pulmonary disease (COPD). Patients and Methods: One hundred sixty one patients aged 50 to 80 years, active or former smokers of 15 or more pack-years and with COPD were enrolled. They underwent annual respiratory functional assessment and chest computed tomography for three years and were followed for five years. Results: Chest CT allowed the detection of lung cancer in nine patients (diagnostic yield: 5.6%). Three cases were detected in the initial CT and six cases in follow-up scans. Most patients were in early stages of the disease (6 stage Ia and 1 stage Ib). Two patients were diagnosed at advanced stages of the disease and died due to complications of cancer. Two thirds of patients had nonspecific pulmonary nodules on the initial chest CT scan (100 patients, 62%). Seventy four percent had less than three nodules and were of less than 5 mm of diameter in 57%. In 92% of cases, these were false positive findings. In the follow-up chest CT, lung nodules were detected in two thirds of patients and 94% of cases corresponded to false positive findings. Conclusions: Chest CT scans may detect lung cancer at earlier stages in COPD patients.

[Pulmonary alveolar microlithiasis: Report of one case]. / Microlitiasis alveolar pulmonar: caso clínico.

Pulmonary alveolar microlithiasis is an extremely rare disease characterized by intra-alveolar accumulation of calcified spherical particles (called microliths), due to a mutation of the gene encoding a membrane transport protein of the alveolar surface. Most patients are asymptomatic at diagnosis. The course of the disease is slowly progressive, with development of pulmonary fibrosis and respiratory failure. The "sandstorm" pattern is the characteristic finding of this disease. We report a 39-year-old female presenting with progressive dyspnea. A chest X ray showed ground-glass opacities and a high resolution CT scan showed numerous calcified lung micronodules. A surgical lung biopsy confirmed the diagnosis of pulmonary alveolar microlithiasis.

Microlitiasis alveolar pulmonar: caso clínico / Pulmonary alveolar microlithiasis: Report of one case

Pulmonary alveolar microlithiasis is an extremely rare disease characterized by intra-alveolar accumulation of calcified spherical particles (called microliths), due to a mutation of the gene encoding a membrane transport protein of the alveolar surface. Most patients are asymptomatic at diagnosis. The course of the disease is slowly progressive, with development of pulmonary fibrosis and respiratory failure. The "sandstorm" pattern is the characteristic finding of this disease. We report a 39-year-old female presenting with progressive dyspnea. A chest X ray showed ground-glass opacities and a high resolution CT scan showed numerous calcified lung micronodules. A surgical lung biopsy confirmed the diagnosis of pulmonary alveolar microlithiasis.

Signos radiológicos: el signo de la galaxia / Radiology signs: the galaxy sign

El signo de la galaxia representa una lesión tipo masa, compuesta por innumerables nódulos granulomatosos coalescentes, más concentrados en el centro que en la periferia. Inicialmente se describió en paciente con sarcoidosis, y se denominó el signo de la galaxia sarcoidea. Actualmente se sabe que puede estar presente en otras entidades como la tuberculosis, el cáncer pulmonar y la fibrosis pulmonar masiva de las neumoconiosis. Es importante su identificación y adecuada interpretación, dado que en asociación con otros signos tomográficos permite una orientación al diagnóstico de sarcoidosis.

The galaxy sign represents a mass-like lesion, composed of innumerable coalescing granulo-matous nodules, more concentrated in the center than at the periphery. It was initially described in patients with sarcoidosis, and was referred to as the "sarcoid galaxy" sign. It is now known to be present in other entities such as tuberculosis, lung cancer and the pulmonary fibrosis mass of pneumoconiosis. Its identification and adequate interpretation is important, given that in association with other tomographic signs it allows an orientation toward the diagnosis of sarcoidosis.

Pólipo fibrovascular esofágico: Estudio por imágenes multimodalidad / Endoluminal excision of an esophageal fibrovascular polyp: Report of one case

We report a 47 years old woman presenting with dysphagia. A chest CAT scan and barium swallow showed an endoluminal mass that extended to four vertebrae. An endoluminal sonography localized the pediculum of the mass, that was excised endoscopically. The pathological study disclosed a fibrovascular polyp. After 18 months of follow up, the patient is asymptomatic.

[Fusion of SPECT with computed tomography or magnetic resonance for the interpretation of abnormal tracer uptake]. / Utilidad clínica de la fusión SPECT/CT con marcadores externos en patología oncológica.

BACKGROUND: Interpretation of abnormal foci with high tracer uptake may require morphological correlation. Fusion of functional images obtained by single photon emission computed tomography (SPECT) and anatomical images obtained by computed tomography (CT) or magnetic resonance (RM) allows an integrated comprehension of complementary information. AIM: To demonstrate that SPECT/CT fusion with external markers is useful in clinical practice to clarify the location and pathological meaning of questionable foci. MATERIAL AND METHODS: Thirty four pairs of images from separate equipments (31 SPECT/CT and 3 SPECT/RM) pertaining to 29 patients, were fused. Fifty one foci of abnormal tracer uptake of uncertain pathological meaning were analyzed. These were classified before and after the fusion as probably malignant or probably benign. RESULTS: Seventy percent of patients had a differentiated thyroid carcinoma. The fusion localized 100% of foci. Nine percent had a normal and 26% an abnormal anatomy. Before fusion 82% of foci were classified as potentially malignant. This figure changed to 59% after the fusion (p <0.01). Therefore the suspicion of malignancy was presumptively confirmed in 72% of foci and fusion results would have reached a 27% of incremental diagnostic value in 14 cases that changed of category (11 with differentiated thyroid carcinoma, one with colorectal cancer, one with a nasal Ewing sarcoma and one with a brain tumor). CONCLUSIONS: The fusion of SPECT and CT is useful in selected patients, specially those with differentiated thyroid carcinoma. The fusion of SPECT and RM is also feasible.

Utilidad clínica de la fusión SPECT/CT con marcadores externos en patología oncológica / Fusion of SPECT with computed tomography or magnetic resonance for the interpretation of abnormal tracer uptake

Background: Interpretation of abnormal foci with high tracer uptake may require morphological correlation. Fusion of functional images obtained by single photon emission computed tomography (SPECT) and anatomical images obtained by computed tomography (CT) or magnetic resonance (RM) allows an integrated comprehension of complementary information. Aim To demonstrate that SPECT/CT fusion with external markers is useful in clinical practice to clarify the location and pathological meaning of questionable foci. Material and methods: Thirty four pairs of images from separate equipments (31 SPECT/CT and 3 SPECT/RM) pertaining to 29 patients, were fused. Fifty one foci of abnormal tracer uptake of uncertain pathological meaning were analyzed. These were classified before and after the fusion as probably malignant or probably benign. Results: Seventy percent of patients had a differentiated thyroid carcinoma. The fusion localized 100 percent of foci. Nine percent had a normal and 26 percent an abnormal anatomy. Before fusion 82 percent of foci were classified as potentially malignant. This figure changed to 59 percent after the fusion (p <0.01). Therefore the suspicion of malignancy was presumptively confirmed in 72 percent of foci and fusion results would have reached a 27 percent of incremental diagnostic value in 14 cases that changed of category (11 with differentiated thyroid carcinoma, one with colorectal cancer, one with a nasalEwingsarcoma and one with a brain tumor). Conclusions: The fusion of SPECT and CT is useful in selected patients, specially those with differentiated thyroid carcinoma. The fusion of SPECT and RM is also feasible.

Evaluación de arterias coronarias con tomografía multicorte / Evaluation of coronary arteries with multislice computed tomography

La resonancia magnética (RM) tiene un tremendo potencial para el estudio de la cardiopatía coronaria. Actualmente la RM en cine es considerada el estándar de referencia para la medición de varios parámetros de función ventricular global como los volúmenes ventriculares, fracción de eyección y masa ventricular. En comparación con otras técnicas, la RM presenta menor variabilidad intra e interobservador en la medición de volúmenes ventriculares. Tiene la ventaja de no utilizar radiación ionizante y es un examen independiente del operador. Con RM también es posible analizar la función miocárdica regional visualizando los distintos segmentos del ventrículo izquierdo durante el ciclo cardiaco. Por otra parte, la RM con uso de gadolinio EV es capaz de mostrar las zonas de infarto y reemplazo fibroso con gran exactitud. Cuando se asocia la detección de fibrosis miocárdica con la evaluación del movimiento segmentario de la pared, es posible predecir recuperación contráctil después de la revascularización.

The magnetic resonance (MR) is a technique in constant evolution for evaluation of coronary artery disease. Cine-MR techniques are currently the main imaging tools for measurement of several parameters of global ventricular function such as ventricular volumes, ejection fraction and the ventricular mass. MR has shown less variability inter-observer than other techniques for measurement of ventricular volumes; it does not use radiation and is operator independent. Regional contractile function is also well assessed by cine-MR with visual inspection of wall motion and thickening for the left ventricle. After gadolinium administration, MR can assess myocardial infarct and replacement fibrosis. When the detection of myocardial fibrosis is associated with segmental wall motion analysis by cine images, it can be possible to predict improvement recover of contractile function after revascularization.

Rol de la resonancia magnética en cardiopatía isquémica / Role of magnetic resonance in ischemic cardiopaty

La resonancia magnética (RM) tiene un tremendo potencial para el estudio de la cardiopatía coronaria. Actualmente la RM en cine es considerada el estándar de referencia para la medición de varios parámetros de función ventricular global como los volúmenes ventriculares, fracción de eyección y masa ventricular. En comparación con otras técnicas, la RM presenta menor variabilidad intra e interobservador en la medición de volúmenes ventriculares. Tiene la ventaja de no utilizar radiación ionizante y es un examen independiente del operador. Con RM también es posible analizar la función miocárdica regional visualizando los distintos segmentos del ventrículo izquierdo durante el ciclo cardiaco. Por otra parte, la RM con uso de gadolinio EV es capaz de mostrar las zonas de infarto y reemplazo fibroso con gran exactitud. Cuando se asocia la detección de fibrosis miocárdica con la evaluación del movimiento segmentario de la pared, es posible predecir recuperación contráctil después de la revascularización.

The magnetic resonance (MR) is a technique in constant evolution for evaluation of coronary artery disease. Cine-MR techniques are currently the main imaging tools for measurement of several parameters of global ventricular function such as ventricular volumes, ejection fraction and the ventricular mass. MR has shown less variability inter-observer than other techniques for measurement of ventricular volumes; it does not use radiation and is operator independent. Regional contractile function is also well assessed by cine-MR with visual inspection of wall motion and thickening for the left ventricle. After gadolinium administration, MR can assess myocardial infarct and replacement fibrosis. When the detection of myocardial fibrosis is associated with segmental wall motion analysis by cine images, it can be possible to predict improvement recover of contractile function after revascularization.

Tromboembolismo pulmonar: venografía por tomografía computada versus ecografía Doppler, para detección de trombosis venosa profunda de extremidades inferiores / Pulmonary embolism: CT venography versus Doppler echography in the diagnostic of deep venous thrombosis at the lower limbs

Resumen: El tromboembolismo pulmonar (TEP) es un cuadro de alta morbimortalidad. La principal fuente embolígena, es la trombosis venosa profunda (TVP) de las extremidades inferiores (EEII), por ello, el estudio de un paciente con sospecha clínica de TEP, incluye la evaluación de estas venas. La venografía por tomografía computada (TC) ha demostrado utilidad en la evaluación de la TVP, existiendo numerosos trabajos que avalan su buena correlación con el Doppler venoso de EEII. Nuestro estudio compara ambos métodos en la detección de TVP de las EEII en estos pacientes. Encontramos una muy buena correlación entre ambos métodos, con una sensibilidad del 100 por ciento y una especificidad de 88,9 por ciento para la venografía por TC comparado con el Doppler, lo que concuerda con lo descrito en la literatura.

Manifestaciones radiográficas de la tuberculosis pulmonar / Radiographic manifestations of pulmonary tuberculosis

La tuberculosis (TBC) es una patología que ha acompañado al hombre desde los comienzos de la historia, y a pesar de que hace más de medio siglo se cuenta con antibióticos eficaces y se puede considerar una enfermedad prevenible, tratable y erradicable, esta meta está lejos de ser alcanzada. En Chile se diagnostican semanalmente entre 40-70 casos, lo que significa que el médico está constantemente enfrentado este cuadro. Por lo general, el diagnóstico se sospecha sobre la base de la sintomatología y antecedentes epidemiológicos, siendo la radiografía de tórax el primer examen de aproximación diagnóstica. Diversos patrones radiológicos, con compromiso parenquimatoso y/o intersticial, son característicos y las manifestaciones son dependientes de la edad del paciente, de su estado inmunológico, de la exposición previa y de sí estamos frente a un cuadro primario o posprimario. Presentamos distintos patrones radiológicos de la TBC pulmonar, en pacientes atendidos durante el primer semestre de este año en el Hospital Clínico de la Universidad de Chile y en el Hospital San Juan de Dios.

Enfoque diagnóstico y terapéutico de los pacientes adultos con sospecha de sinusitis aguda / Diagnosis and treatment of adult patients with acute sinusitis suspicion

La sinusitis aguda bacteriana es una causa frecuente de consulta ambulatoria de pacientes adultos y debe ser distinguida de aquellos casos con etiología viral. Un alto porcentaje de los casos tiende a la resolución espontánea sin el concurso de un tratamiento antimicrobiano, aunque esta opción terapéutica permite acortar el período sintomático y aliviar la intensidad de los síntomas. Para reconocer adecuadamente los casos de sinusitis aguda bacteriana se dispone de diferentes estrategias diagnósticas. La alternativa de referencia, la punción sinusal con cultivo, es de carácter invasor y no es aplicable en atención primaria. La detección de casos mediante el reconocimiento de algunos síntomas y signos específicos ofrece una sensibilidad y especificidad razonable, similar al rendimiento asociado al estudio radiológico convencional y además de menor costo. El diagnóstico por ecografía o tomografía axial computarizada no incrementa los valores asociados a las estrategias señaladas. Amoxicilina continúa siendo el fármaco de elección en el manejo de esta condición, debido a su demostrada eficacia, tolerancia y bajo costo. El advenimiento de nuevos compuestos no ha superado la eficacia asociada a amoxicilina, así como tampoco la emergencia de aislamientos de S. pneumoniae o H. influenzae resistentes a penicilina ha limitado su utilidad clínica. La alta resistencia ante cotrimoxazol presente en aislamientos nacionales de S. pneumoniae impide su recomendación en nuestro medio como un antimicrobiano de primera línea. Los pacientes deben ser tratados por un período de 10 días.