Colin J. McCarthy

Hepatocellular Carcinoma: Illustrated Guide to Systematic Radiologic Diagnosis and Staging According to Guidelines of the American Association for the Study of Liver Diseases

Hepatocellular carcinoma is a malignancy that predominantly occurs in the setting of cirrhosis. Its incidence is rising worldwide. Hepatocellular carcinoma differs from most malignancies because it is commonly diagnosed on the basis of imaging features alone, without histologic confirmation. The guidelines from the American Association for the Study of Liver Diseases (AASLD) are a leading statement for the diagnosis and staging of hepatocellular carcinoma, and they have recently been updated, incorporating several important changes. AASLD advocates the use of the Barcelona Clinic Liver Cancer (BCLC) staging system, which combines validated imaging and clinical predictors of survival to determine stage and which links staging with treatment options. Each stage of the BCLC system is outlined clearly, with emphasis on case examples. Focal liver lesions identified at ultrasonographic surveillance in patients with cirrhosis require further investigation. Lesions larger than 1 cm should be assessed with multiphasic computed tomography or magnetic resonance imaging. Use of proper equipment and protocols is essential. Lesions larger than 1 cm can be diagnosed as hepatocellular carcinoma from a single study if the characteristic dynamic perfusion pattern of arterial hyperenhancement and venous or delayed phase washout is demonstrated. If the imaging characteristics of hepatocellular carcinoma are not met, the alternate modality should be performed. Biopsy should be used if neither modality is diagnostic of hepatocellular carcinoma. Once the diagnosis has been made, the cancer should be assigned a BCLC stage, which will help determine suitable treatment options. Radiologists require a systematic approach to diagnose and stage hepatocellular carcinoma with appropriate accuracy and precision.

Rapid needle-out patient-rollover time after percutaneous CT-guided transthoracic biopsy of lung nodules: effect on pneumothorax rate.

PURPOSE To assess the effect of a rapid needle-out patient-rollover time approach on the rate of pneumothorax after computed tomography (CT)-guided transthoracic needle biopsy of pulmonary nodules. MATERIALS AND METHODS The institutional review board approved the study, and all patients gave written informed consent. Between January 2008 and December 2009, percutaneous CT-guided lung biopsy was performed in 201 patients. Eighty-one biopsies were performed without (group 1) and 120 were performed with (group 2) a rapid needle-out patient-rollover time approach (defined as the time between removal of the biopsy needle and placing the patient biopsy-side down). Multivariate analysis was performed between groups for risk factors for pneumothorax, including patient demographic characteristics, lesion characteristics, and biopsy technique. RESULTS Mean rapid needle-out patient-rollover time (± standard deviation) was 9.5 seconds ± 4.8. Seventy-six percent of patients (75 of 98) achieved a needle-out patient-rollover time of 10 seconds or less. Unsuitability for the rapid needle-out patient-rollover time technique resulted in exclusion of 1.8% of patients. An increased number of pneumothoraces (25 [37%] vs 22 [23%]; P = .04) and an increased number of drainage catheter insertions were noted in group 1 compared with group 2 (10 [15%] versus four [4%], respectively; P = .029). At multiple regression analysis for group 1, lesion size and emphysema along the needle track were independent risk factors for pneumothorax (P = .032 and .021, respectively), and emphysema along the needle track was an independent predictor for insertion of a drainage catheter (P = .005). No independent predictor was identified for pneumothorax or insertion of a drainage catheter in group 2. CONCLUSION Rapid needle-out patient-rollover time during percutaneous CT-guided transthoracic lung biopsy reduces the rate of overall pneumothorax and pneumothorax necessitating a drainage catheter. Use of this technique attenuates the influence of traditional risk factors for pneumothorax.

Air Embolism: Diagnosis, Clinical Management and Outcomes

Air embolism is a rare but potentially fatal complication of surgical procedures. Rapid recognition and intervention is critical for reducing morbidity and mortality. We retrospectively characterized our experience with air embolism during medical procedures at a tertiary medical center. Electronic medical records were searched for all cases of air embolism over a 25-year period; relevant medical and imaging records were reviewed. Sixty-seven air embolism cases were identified; the mean age was 59 years (range, 3–89 years). Ninety-four percent occurred in-hospital, of which 77.8% were during an operation/invasive procedure. Vascular access-related procedures (33%) were the most commonly associated with air embolism. Clinical signs and symptoms were related to the location the air embolus; 36 cases to the right heart/pulmonary artery, 21 to the cerebrum, and 10 were attributed to patent foramen ovale (PFO). Twenty-one percent of patients underwent hyperbaric oxygen therapy (HBOT), 7.5% aspiration of the air, and 63% had no sequelae. Mortality rate was 21%; 69% died within 48 hours. Thirteen patients had immediate cardiac arrest where mortality rate was 53.8%, compared to 13.5% (p = 0.0035) in those without. Air emboli were mainly iatrogenic, primarily associated with endovascular procedures. High clinical suspicion and early treatment are critical for survival.

Air Embolism: Practical Tips for Prevention and Treatment

Air embolism is a rarely encountered but much dreaded complication of surgical procedures that can cause serious harm, including death. Cases that involve the use of endovascular techniques have a higher risk of air embolism; therefore, a heightened awareness of this complication is warranted. In particular, central venous catheters and arterial catheters that are often placed and removed in most hospitals by a variety of medical practitioners are at especially high risk for air embolism. With appropriate precautions and techniques it can be preventable. This article reviews the causes of air embolism, clinical management and prevention techniques.

Ivacaftor Imaging Response in Cystic Fibrosis

A 27-year-old Irish adult with cystic fibrosis (CF; DF508/G551D genotype) was commenced on ivacaftor in January 2011. Ivacaftor addresses the underlying cause of CF in individuals with the G551D genotype by increasing chloride transport through cell surface CF transmembrane conductance regulator. Before this, he suffered two to three respiratory exacerbations per year, none requiring hospital admission. Sputum was positive for Staphylococcus aureus and Pseudomonas aeruginosa. After 2 years of treatment, the patient’s FEV1 increased from 79% predicted to 95% predicted, and he was completely free of respiratory exacerbations during this time. A previous chest computed tomography scan (CT) in 2011 showed mild diffuse bilateral upper lobe bronchiectasis (Figure 1A, arrowhead), mild diffuse airway wall thickening (straight arrows) and diffuse mucus plugging (curved arrows). A follow-up chest CT in 2013 showed stabilization of bronchiectasis (Figure 1B, arrowhead), marked improvement in airway wall thickening (straight arrows), and extensive clearing of mucus plugging (curved arrows). The stabilization of bronchiectasis and reduction in airway thickening and mucus plugging demonstrated by CT in this patient correlate with his improvement in lung function and are likely a result of chronic therapy with ivacaftor. High-resolution CT imagingmay be a useful tool to gauge response to therapy with ivacaftor for patients with CF with the G551D mutation. n

Evaluation of the Particulate Concentration in a Gelatin-Based Phantom for Sonographically Guided Lesion Biopsy

The purpose of this study was to determine the particulate concentration in a gelatin‐based ultrasound phantom for lesion biopsy at 6 cm in depth to reduce visualization of the biopsy needle in the near field, simulating subcutaneous fat and tissue echogenicity, and maintain target lesion visualization.

Images of pheochromocytoma in adrenal glands

Pheochromocytomas are relatively rare tumors of the adrenal medulla. A wide spectrum of imaging findings has been described. The aim of this article is to describe the multimodality imaging features of pheochromocytomas including diagnostic pearls that can help differentiate them from other adrenal lesions and pitfalls to avoid.

GIST with a twist--upregulation of PDGF-B resulting in metachronous gastrointestinal stromal tumor and dermatofibrosarcoma protuberans.

Case ReportA 61-year-old male was referred following an incidental radiological discovery of an intra-abdominal mass. His medical history included excision of a lumbar dermatofibrosarcoma protuberans (DFSP) 5 years previously. A CT scan of the abdomen revealed a mass arising from the greater curvature of the stomach. Upper GI endoscopy was normal. He underwent successful laparoscopic resection of this mass.Materials and MethodsThe histology of the abdominal mass revealed a gastrointestinal stromal tumor (GIST) with poor prognostic indicators. Immunohistochemical analysis of the GIST and his previous DFSP was performed.ResultsImmunohistochemistry suggested a link between the GIST and his previous DFSP involving the PDGF signalling system.DiscussionBoth GIST and DFSP are extremely rare tumors. A mutation in the platelet-derived growth factor receptor alpha (PDGFR-α) has been described in 5–15% of GISTs. It has been shown that DFSP is frequently associated with a translocation between PDGF-B (Chr 22) and COL1A1 (Chr 17), causing continuous activation of PDGFR-β. Literature review confirms that there are no previously reported cases of both of these tumors occurring in the same patient.ConclusionWe hypothesize that this patient may have a previously undescribed genetic mutation involving the PDGF signalling system, resulting in these two very rare malignancies. Immunohistochemistry studies confirmed the link on this occasion. Improvements in our understanding of the molecular biology of the PDGF system may novel therapeutic targets in the future.

Decision Making: Thermal Ablation Options for Small Renal Masses

Renal cell carcinoma is a relatively common tumor, with an estimated 63,000 new cases being diagnosed in the United States in 2016. Surgery, be it with partial or total nephrectomy, is considered the mainstay of treatment for many patients. However, those patients with small renal masses, typically less than 3 to 4 cm in size who are deemed unsuitable for surgery, may be suitable for percutaneous thermal ablation. We review the various treatment modalities, including radiofrequency ablation, microwave ablation, and cryoablation; discuss the advantages and disadvantages of each method; and review the latest data concerning the performance of the various ablative modalities compared with each other, and compared with surgery.

Chest CT abnormalities and quality of life: relationship in adult cystic fibrosis

BACKGROUND To evaluate the relationship between lung parenchymal abnormalities on chest CT and health-related quality of life in adult cystic fibrosis (CF). METHODS The chest CT scans of 101 consecutive CF adults (mean age 27.8±7.9, 64 males) were prospectively scored by two blinded radiologists in consensus using a modified Bhalla score. Health-related quality of life was assessed using the revised Quittner Cystic Fibrosis Questionnaire (CFQ-R). Multiple regressions were performed with each of the CFQ-R domains and all clinical and imaging findings to assess independent correlations. RESULTS There were 18 inpatients and 83 outpatients. For the cohort of inpatients, CT abnormalities were significantly (P<0.005 for all) associated with Respiratory Symptoms (Air Trapping), and also with Social Functioning (Consolidation) and Role Functioning (Consolidation). For outpatients, CT abnormalities were significantly (P<0.005 for all) associated with Respiratory Symptoms (Consolidation) and also with Physical Functioning (Consolidation), Vitality (Consolidation, Severity of Bronchiectasis), Eating Problems (airway wall thickening), Treatment Burden (Total CT Score), Body Image (Severity of Bronchiectasis) and Role Functioning (Tree-in-bud nodules). Consolidation was the commonest independent CT predictor for both inpatients (predictor for 2 domains) and outpatients (predictor in 3 domains). Several chest CT abnormalities excluded traditional measures such as FEV1 and BMI from the majority of CFQ-R domains. CONCLUSIONS Chest CT abnormalities are significantly associated with quality of life measures in adult CF, independent of clinical or spirometric measurements.