Oklu, Rahmi

The gastroduodenal artery (GDA) is frequently embolized in cases of upper GI bleed that has failed endoscopic therapy. Additionally, it may be done for GDA pseudoaneurysms or as an adjunctive procedure prior to Yttrim-90 (Y90) treatment of hepatic tumors. This clinical review will summarize anatomy and embryology of the GDA, indications, outcomes and complications of GDA embolization.

Of all procedures in interventional radiology, percutaneous transhepatic biliary drainage (PTBD) is amongst the most technically challenging. Successful placement requires a high level of assorted skills. While this procedure can be life-saving, it can also lead to significant iatrogenic harm, often manifesting as bleeding. Readers of this article will come to understand the pathophysiology and anatomy underlying post-PTBD bleeding, its incidence, its varied clinical manifestations and its initial management. Additionally, a structured approach to its treatment emphasizing endovascular and percutaneous methods is given.

Cross-sectional imaging has become a critical aspect in the evaluation of arterial injuries. In particular, angiography using computed tomography (CT) is the imaging of choice. A variety of techniques and options are available when evaluating for arterial injuries. Techniques involve contrast bolus, various phases of contrast enhancement, multiplanar reconstruction, volume rendering, and maximum intensity projection. After the images are rendered, a variety of features may be seen that diagnose the injury. This article provides a general overview of the techniques, important findings, and pitfalls in cross sectional imaging of arterial imaging, particularly in relation to computed tomography. In addition, the future directions of computed tomography, including a few techniques in the process of development, is also discussed.

Colovaginal and/or rectovaginal fistulas cause significant and distressing symptoms, including vaginitis, passage of flatus/feces through the vagina, and painful skin excoriation. These fistulas can be a challenging condition to treat. Although most fistulas can be treated with surgical repair, for those patients who are not operative candidates, limited options remain. As minimally-invasive interventional techniques have evolved, the possibility of fistula occlusion has enriched the therapeutic armamentarium for the treatment of these complex patients. In order to offer optimal treatment options to these patients, it is important to understand the imaging and anatomical features which may appropriately guide the surgeon and/or interventional radiologist during pre-procedural planning.

Quadrilateral space syndrome (QSS) is a rare disorder characterized by axillary nerve and posterior humeral circumflex artery (PHCA) compression within the quadrilateral space. Impingement is most frequently due to trauma, fibrous bands, or hypertrophy of one of the muscular borders. Diagnosis can be complicated by the presence of concurrent traumatic injuries, particularly in athletes. Since many other conditions can mimic QSS, it is often a diagnosis of exclusion. Conservative treatment is often first trialed, including physical exercise modification, physical therapy, and therapeutic massage. In patients unrelieved by conservative measures, surgical decompression of the quadrilateral space may be indicated.

Genotype, particularly Ras status, greatly affects prognosis and treatment of liver metastasis in colon cancer patients. This pilot aimed to apply word frequency analysis and a naive Bayes classifier on radiology reports to extract distinguishing imaging descriptors of wild-type colon cancer patients and those with v-Ki-ras2 Kirsten rat sarcoma viral oncogene homolog (KRAS) mutations. In this institutional-review-board-approved study, we compiled a SNaPshot mutation analysis dataset from 457 colon adenocarcinoma patients. From this cohort of patients, we analyzed radiology reports of 299 patients (> 32,000 reports) who either were wild-type (147 patients) or had a KRAS (152 patients) mutation. Our algorithm determined word frequency within the wild-type and mutant radiology reports and used a naive Bayes classifier to determine the probability of a given word belonging to either group. The classifier determined that words with a greater than 50% chance of being in the KRAS mutation group and which had the highest absolute probability difference compared to the wild-type group included: “several”, “innumerable”, “confluent”, and “numerous” (p < 0.01). In contrast, words with a greater than 50% chance of being in the wild type group and with the highest absolute probability difference included: “few”, “discrete”, and “[no] recurrent” (p = 0.03). Words used in radiology reports, which have direct implications on disease course, tumor burden, and therapy, appear with differing frequency in patients with KRAS mutations versus wild-type colon adenocarcinoma. Moreover, likely characteristic imaging traits of mutant tumors make probabilistic word analysis useful in identifying unique characteristics and disease course, with applications ranging from radiology and pathology reports to clinical notes.