Fluoroscopy: An essential diagnostic modality in the age of high-resolution cross-sectional imaging

The importance of fluoroscopy as an imaging modality has been minimized relative to other cross-sectional modalities, including high-resolution computed tomography (CT), magnetic resonance imaging (MRI) and ultrasound. Fluoroscopy examinations have decreased in clinical practice due to reduced appreciation of its usefulness, insufficient training of residents, fewer staff with adequate expertise, and poor reimbursements relative to other modalities. We revisit and build upon the prior literature and history of this decreased utilization. We then seek to prove continued value, through categorized examples and within multiple subspecialties, wherein fluoroscopy plays an integral part toward clinical diagnoses as well as optimizing patient outcomes. This is particularly true for motility and esophageal disorders, where structure and function with real-time evaluation is essential.  We additionally show several post-operative cases where the synergy of fluoroscopy with CT and endoscopy is apparent.  The fluoroscopic radiologist also has the unique ability to vary patient positioning, as opposed to traditional CT or MRI, where orthogonal views are employed without positional or temporal changes. We turn attention to the modern era, with synergistic and novel cases demonstrating that fluoroscopy remains instrumental toward achieving a diagnosis alongside other modalities. Our cases stress the need to maintain expertise in fluoroscopy skill, and underline its continued importance in residency training programs.  We conclude that fluoroscopy is a relatively inexpensive modality that is often under-appreciated in diagnostic radiology. We suggest that competency in fluoroscopy is crucial for future generations of radiologists to both work with their peers, as well as to aid clinicians in the optimal treatment of patients.

PET and CT features differentiating infectious/inflammatory from malignant mediastinal lymphadenopathy: A correlated study with endobronchial ultrasound-guided transbronchial needle aspiration

Purpose:

To explore the advantages of differentiating inflammatory from malignant thoracic lymph nodes by integrating their features on positron emission tomography (PET) and computed tomography (CT).

Material and method:

Following institutional review board approval, PET and CT parameters of thoracic lymph nodes were examined based on their pathologic diagnosis via endobronchial ultrasound-guided transbronchial needle aspiration. The standardized uptake value (SUV) of PET and CT findings of the long- and short-axis diameters, axial short to long diameter ratios (S/L), and measured nodal CT values of the lymph nodes were compared and analyzed statistically.

Results:

A total of 124 lymph nodes from 70 patients were studied. The inflammatory and malignant lymph nodes differed significantly in their SUV (P = 0.008), short-axis diameters (SAD, p < 0.001), long-axis diameters (LAD, p = 0.002) and S/L ratios (p < 0.001). They did not differ significantly in non-contrast enhanced CT values (p = 0.304). The sensitivities, specificities, positive predictive values, negative predictive values, diagnostic accuracies and diagnostic odds ratios (DOR) were: 1) elevated SUV alone - 95.31% (61/64), 20% (12/60), 55.96% (61/109), 80% (12/15), 58.87% (73/124), and 5; 2) combined SUV + SAD - 89.06%, 53.33%, 67.06%, 82.05%, 71.77%, and 9.31; 3) combined SUV + S/L ratio - 87.5%, 93.33%, 93.33%, 87.5%, 90.32%, and 98, respectively.

Conclusion:

Increased SUV, SAD, LAD, and S/L ratio are accurate PET/CT parameters to characterize inflammatory or malignant lymph nodes. SUV has high sensitivity but low specificity, low positive and negative predictive values, and low DOR. The SUV + SAD and SUV + S/L ratios have higher specificity, positive and negative predictive values, diagnostic accuracy and DOR.