Imaging of Chronic Thromboembolic Disease.

Acute pulmonary embolism (PE) is a leading cause of cardiovascular morbidity. The most common long-term complication of acute PE is chronic thromboembolic disease, a heterogenous entity which ranges from asymptomatic imaging sequelae to persistent symptoms. Chronic thromboembolic pulmonary hypertension (CTEPH) is a rare disease that can develop in this population and represents the only treatable type of pulmonary hypertension. Recognition of the characteristic findings of chronic pulmonary embolism and CTEPH provides not only diagnostic information, but is also crucial for guiding therapy. The present state-of-the-art review focuses on the multimodality imaging features of chronic pulmonary embolism. Detailed description and illustrations of relevant imaging findings will be demonstrated for ventilation/perfusion (V/Q) scan, CT scan and Dual-Energy CT and MRI and features that distinguish chronic PE from common imaging mimics.

Single-subject classification of presymptomatic frontotemporal dementia mutation carriers using multimodal MRI.

Background: Classification models based on magnetic resonance imaging (MRI) may aid early diagnosis of frontotemporal dementia (FTD) but have only been applied in established FTD cases. Detection of FTD patients in earlier disease stages, such as presymptomatic mutation carriers, may further advance early diagnosis and treatment. In this study, we aim to distinguish presymptomatic FTD mutation carriers from controls on an individual level using multimodal MRI-based classification. Methods: Anatomical MRI, diffusion tensor imaging (DTI) and resting-state functional MRI data were collected in 55 presymptomatic FTD mutation carriers (8 microtubule-associated protein Tau, 35 progranulin, and 12 chromosome 9 open reading frame 72) and 48 familial controls. We calculated grey and white matter density features from anatomical MRI scans, diffusivity features from DTI, and functional connectivity features from resting-state functional MRI. These features were applied in a recently introduced multimodal behavioural variant FTD (bvFTD) classification model, and were subsequently used to train and test unimodal and multimodal carrier-control models. Classification performance was quantified using area under the receiver operator characteristic curves (AUC). Results: The bvFTD model was not able to separate presymptomatic carriers from controls beyond chance level (AUC = 0.570, p = 0.11). In contrast, one unimodal and several multimodal carrier-control models performed significantly better than chance level. The unimodal model included the radial diffusivity feature and had an AUC of 0.646 (p = 0.021). The best multimodal model combined radial diffusivity and white matter density features (AUC = 0.680, p = 0.005). Conclusions: FTD mutation carriers can be separated from controls with a modest AUC even before symptom-onset, using a newly created carrier-control classification model, while this was not possible using a recent bvFTD classification model. A multimodal MRI-based classification score may therefore be a useful biomarker to aid earlier FTD diagnosis. The exclusive selection of white matter features in the best performing model suggests that the earliest FTD-related pathological processes occur in white matter.

Acute zonal occult outer retinopathy: a classification based on multimodal imaging.

IMPORTANCE: We describe the multimodal imaging in a group of patients showing a distinct clinical entity that best represents acute zonal occult outer retinopathy (AZOOR). OBJECTIVE: To propose a classification of AZOOR based on clinical fundus and multimodal imaging. DESIGN, SETTING AND PARTICIPANTS: A retrospective review of patients diagnosed as having AZOOR at 2 centers. After reviewing more than 400 cases diagnosed or referred to us as AZOOR or AZOOR complex, we assembled 30 cases that fit our current definition; (48 eyes) with a median age at diagnosis of 47 years (age range, 17-86 years) and a mean follow-up period of 39 months. Twenty patients were female. Eighteen patients had initially been seen with bilateral lesions, mostly asymmetric (4 cases were symmetric). Most patients had no remarkable medical or ocular history. The median visual acuity at the time of presentation was 20/25 (range, 20/20 to 20/400). MAIN OUTCOMES AND MEASURES: Multimodal imaging, including fundus photography, fluorescein and indocyanine green angiography, fundus autofluorescence imaging, and corresponding eye-tracked spectral-domain coherence tomography imaging. RESULTS: Each patient was initially seen with visual symptoms of photopsia and scotoma, and most had a detectable lesion in the fundus evident clinically or detected on multimodal imaging. The clinical appearance of the AZOOR lesions varied depending on their duration and location, but some features were characteristic, including a demarcating line of the progression at the level of the outer retina and a trizonal pattern of sequential involvement of the outer retina, retinal pigment epithelium, and choroid, as well as frequent zonal progression. Advanced cases of AZOOR demonstrated disruption of the inner and outer retina and severe damage or loss of the retinal pigment epithelium and the choroid. CONCLUSIONS AND RELEVANCE: A specific definition of AZOOR based on multimodal imaging is proposed to help physicians distinguish it from other diseases of the posterior fundus, including white spot syndromes and autoimmune, hereditary, paraneoplastic, toxic, and other inflammatory retinopathies.

Cáncer de mama re-estadificado con PET/CT / The restaging of breast cancer with PET/CT

El cáncer de mama constituye el tipo de malignidad más frecuente en las mujeres, con un 26% de todos los cánceres femeninos, según publicaciones internacionales. De acuerdo con estadísticas nacionales, entre 2000 y 2006 hubo más de 10.000 fallecimientos por esta causa. El incremento en la disponibilidad y mejoras tecnológicas en cuanto al diagnóstico por imagen soportan un proceso de etapificación más completa en este tipo de pacientes. La tomografía por emisión de positrones (PET) ha mostrado gran impacto en la re-estadificación y detección de metástasis en pacientes con cáncer. Se presenta el caso de una paciente con carcinoma de mama y sospecha de recaída, la cual fue confirmada mediante PET/CT con hallazgos de enfermedad metastásica ganglionar y ósea.

Breast cancer represents the most frequent malignancy in women, accounting for 26% of all female cancers, according to international publications. During the period 2000 to 2006, more than 10,000 breast cancer deaths were recorded in Colombia. Greater availability of advanced technology for image based diagnosis buttresses an improved staging process for patients with this disease. Positron emission tomography (PET) has made an enormous impact on the restaging and metastasis detection in cancer patients. A case study is presented of a breast cancer patient suspected of relapse, subsequently confirmed by PET/CT which revealed lymph node and bone metastasis.