Gregory Kicska
University of Washington
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Featured researches published by Gregory Kicska.
Radiographics | 2013
Christopher M. Walker; David A. Saldaña; Gregory W. Gladish; Demetrius L. Dicks; Gregory Kicska; Lee M. Mitsumori; Gautham P. Reddy
As survival rates continue to increase for patients with childhood and adult malignancies, imaging utilization in these patients will likely increase substantially. It is important to detect disease recurrence and to recognize the potential complications that occur after treatment with oncologic medications and therapeutic radiation. The most common cardiotoxic side effect of the anthracycline drug class is a dose-dependent decline in ejection fraction, which may result in dilated cardiomyopathy. Multiple-uptake gated acquisition (MUGA) scanning plays an important role in diagnosis of this subclinical cardiac dysfunction. Other less common cardiotoxic side effects of chemotherapeutic medications include arrhythmia, myocarditis, coronary artery disease, tamponade, pericarditis, and pericardial effusion. Radiation therapy can also lead to cardiotoxicity when the heart or pericardium is included in the radiation portal. Radiation-induced conditions include pericardial disease, coronary artery disease, valvular disease, and cardiomyopathy. Many of these side effects are asymptomatic until late in the course of the disease. With imaging, these pathologic conditions can often be diagnosed before symptom onset, which may allow early intervention. Radiologists should be familiar with the current knowledge and pathophysiology regarding cardiac complications related to chemotherapy and radiation therapy of malignant neoplasms and the appearances of treatment-related cardiotoxicity that can be found at radiography, nuclear medicine examinations, and cross-sectional imaging. Supplemental material available at http://radiographics.rsna.org/lookup/suppl/doi:10.1148/rg.336125005/-/DC1.
International Journal of Cardiovascular Imaging | 2013
Abhishek Chaturvedi; Randy Lau; Gregory Kicska; Gautham P. Reddy
Congenital or acquired communication between left ventricle and right atrium is rare and can be easily overlooked as an eccentric tricuspid regurgitation jet. MRI is the ideal modality for accurate diagnosis, providing details for surgical planning about the location and size of the defect.
Journal of Thoracic Imaging | 2014
Daniel Ocazionez; Demetrius L. Dicks; Jennifer L. Favinger; Girish S. Shroff; Sidhdharth Damani; Gregory Kicska; Gautham P. Reddy
Patient safety is a priority for patients undergoing magnetic resonance imaging (MRI). This article reviews MRI safety issues related to devices, pharmacologic stress agents, contrast agents, anesthesia, and external equipment, focusing on cardiothoracic MRI.
Radiology | 2017
Tina D. Tailor; Gregory Kicska; Jill E. Jacobs; Miguel H. Pampaloni; Diana Litmanovich; Gautham P. Reddy
Ischemic heart disease is the number one cause of death of women in the United States, accounting for over a quarter of a million annual female deaths. Evidence within the last several decades supports sex-specific differences in the prevalence, symptoms, and prognosis of ischemic heart disease between men and women. Despite women having a lower burden of obstructive coronary artery disease compared with men, the prevalence of angina and mortality from ischemic heart disease is higher for women than men. In addition to ischemic heart disease, certain nonischemic conditions may also have sex-specific differences in clinical presentation and occurrence. With the rising utilization of noninvasive modalities for the diagnosis and management of ischemic heart disease, it is important for radiologists to be familiar with the unique considerations for imaging women with heart disease. The purpose of this review is to discuss challenges for detection of heart disease in women, examine performance of noninvasive modalities in the detection of ischemic heart disease, and discuss nonischemic cardiomyopathies unique to or prevalent in women. Considerations for cardiac imaging in pregnancy are also discussed.
Clinical Imaging | 2016
Rachael M. Edwards; Gautham P. Reddy; Gregory Kicska
Functional single ventricle (FSV) encompasses a spectrum of severe congenital heart disease. Patients with FSV are living longer than decades prior resulting in more frequent imaging both for surgical planning and functional evaluation. At each stage of surgical intervention, imaging plays a critical role in detecting postoperative complications and preprocedural planning. This article describes the unique imaging findings, including complications, that are most important to the referring physician or surgeon at each surgical stage of FSV management. A description of lesions that embody the diagnosis of FSV is also included.
Journal of Biomechanical Engineering-transactions of The Asme | 2015
Alexander I. Veress; George S. K. Fung; Taek Soo Lee; Benjamin M. W. Tsui; Gregory Kicska; W. Paul Segars; Grant T. Gullberg
This paper describes the process in which complex lesion geometries (specified by computer generated perfusion defects) are incorporated in the description of nonlinear finite element (FE) mechanical models used for specifying the motion of the left ventricle (LV) in the 4D extended cardiac torso (XCAT) phantom to simulate gated cardiac image data. An image interrogation process was developed to define the elements in the LV mesh as ischemic or infarcted based upon the values of sampled intensity levels of the perfusion maps. The intensity values were determined for each of the interior integration points of every element of the FE mesh. The average element intensity levels were then determined. The elements with average intensity values below a user-controlled threshold were defined as ischemic or infarcted depending upon the model being defined. For the infarction model cases, the thresholding and interrogation process were repeated in order to define a border zone (BZ) surrounding the infarction. This methodology was evaluated using perfusion maps created by the perfusion cardiac-torso (PCAT) phantom an extension of the 4D XCAT phantom. The PCAT was used to create 3D perfusion maps representing 90% occlusions at four locations (left anterior descending (LAD) segments 6 and 9, left circumflex (LCX) segment 11, right coronary artery (RCA) segment 1) in the coronary tree. The volumes and shapes of the defects defined in the FE mechanical models were compared with perfusion maps produced by the PCAT. The models were incorporated into the XCAT phantom. The ischemia models had reduced stroke volume (SV) by 18-59 ml. and ejection fraction (EF) values by 14-50% points compared to the normal models. The infarction models, had less reductions in SV and EF, 17-54 ml. and 14-45% points, respectively. The volumes of the ischemic/infarcted regions of the models were nearly identical to those volumes obtained from the perfusion images and were highly correlated (R² = 0.99).
Journal of Cystic Fibrosis | 2017
Siddhartha G. Kapnadak; Gregory Kicska; Kathleen J. Ramos; Desiree A. Marshall; Tamara Y. Carroll; Sudhakar Pipavath; Michael S. Mulligan; Christopher H. Goss; Moira L. Aitken
BACKGROUND Tracheal diverticula (TD) are rare anomalies that may harbor infected secretions, posing potential risk to patients with lung disease. In an end-stage cystic fibrosis (CF) cohort, we describe the characteristics and associated post-lung transplant (LTx) outcomes of TD. METHODS Pre-transplant computed tomography (CT)s were reviewed in CF patients undergoing LTx. TD were characterized radiographically and on autopsy when available. Pre-transplant clinical variables and post-transplant outcomes were compared by TD status. RESULTS Of 93 patients, 35 (37.6%) had TD. 58% of TD had fat-stranding, and post-mortem TD examinations revealed histology carrying intense submucosal inflammation, and purulent contents that cultured identical species to sputum. There was no difference in post-LTx survival [HR 1.77 (0.82-3.82), p=0.147], bacterial re-colonization, or rejection in patients with TD compared to those without. Patients with TD were more likely to die from infection, but the result was not statistically significant [HR 2.02 (0.62-6.63), p=0.245]. CONCLUSIONS We found a high prevalence of TD in end-stage CF, where diverticula may represent a large-airway bacterial reservoir. TD were not associated with differences in post-LTx outcomes, but given the infectious concerns further investigation is necessary.
Journal of Computer Assisted Tomography | 2016
Rachael M. Edwards; J. David Godwin; Dan S. Hippe; Gregory Kicska
Objective It is known that atelectasis demonstrates greater contrast enhancement than pneumonia on computed tomography (CT). However, the effectiveness of using a Hounsfield unit (HU) threshold to distinguish pneumonia from atelectasis has never been shown. The objective of the study is to demonstrate that an HU threshold can be quantitatively used to effectively distinguish pneumonia from atelectasis. Methods Retrospectively identified CT pulmonary angiogram examinations that did not show pulmonary embolism but contained nonaerated lungs were classified as atelectasis or pneumonia based on established clinical criteria. The HU attenuation was measured in these nonaerated lungs. Receiver operating characteristic (ROC) analysis was performed to determine the area under the ROC curve, sensitivity, and specificity of using the attenuation to distinguish pneumonia from atelectasis. Results Sixty-eight nonaerated lungs were measured in 55 patients. The mean (SD) enhancement was 62 (18) HU in pneumonia and 119 (24) HU in atelectasis (P < 0.001). A threshold of 92 HU diagnosed pneumonia with 97% sensitivity (confidence interval [CI], 80%–99%) and 85% specificity (CI, 70–93). Accuracy, measured as area under the ROC curve, was 0.97 (CI, 0.89–0.99). Conclusions We have established that a threshold HU value can be used to confidently distinguish pneumonia from atelectasis with our standard CT pulmonary angiogram imaging protocol and patient population. This suggests that a similar threshold HU value may be determined for other scanning protocols, and application of this threshold may facilitate a more confident diagnosis of pneumonia and thus speed treatment.
Clinics in Chest Medicine | 2015
Rachael M. Edwards; Gregory Kicska; Rodney A. Schmidt; Sudhakar Pipavath
High-resolution chest computed tomography (CT) is one of the most useful techniques available for imaging bronchiolitis because it shows highly specific direct and indirect imaging signs. The distribution and combination of these various signs can further classify bronchiolitis as either cellular/inflammatory or fibrotic/constrictive. Emphysema is characterized by destruction of the airspaces, and a brief discussion of imaging findings of this class of disease is also included. Typical CT findings include destruction of airspace, attenuated vasculatures, and hyperlucent as well as hyperinflated lungs.
Respiratory Care | 2013
Alan C Kwan; Sudhakar Pipavath; Peter J. Leary; Gregory Kicska
Lung transplant patients commonly undergo transbronchial biopsy to evaluate for rejection. Post-biopsy radiographs are used to exclude pneumothorax, one of the most common major complications. We report a lung transplant patient who developed a pneumothorax 5 months after transbronchial biopsy, with multiple intervening chest computed tomograms documenting that the pneumothorax developed from the biopsy site. This case illustrates that in transplant patients transbronchial biopsy can evolve to pneumothorax several months later, despite normal post-biopsy radiographs.