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Here in our personalized cancer care era, accurate staging and imaging are foundational for optimal treatment recommendations. Radiation oncologists are increasingly dependent upon diagnostic rads for precise identification and enumeration of metastatic disease to guide that therapy.

The Magic Word: As Christopher Straka, MD, noted in the ARRS Online Course Radiation Oncology for the Diagnostic Radiologist, many patients are managed primarily by medical oncologists—who may only trigger a referral to a rad onc if they see the specific term: oligometastatic.

So, to open up the black box of rad onc and improve outcomes, Dr. Straka shared some suggestions:

• Enumerate: Provide a clear count of metastatic sites in your impression.
• Prostate-Specific: For PSMA PET scans, specifically enumerate the number of extra-axial metastases.
• Resolve Equivocals: If a lesion is uncertain, don’t just call it equivocal; please suggest the next modality that would provide more certainty.
• Breadcrumbs: Use arrows, annotations, and slice numbers to help rad oncs quickly locate targets.

RadFYI: Effective communication between rads and treating oncs has never been more important for metastasis-directed therapy. Ultimately, for the complex cases, direct consultation is still everyone’s best bet.

Posterior shoulder dislocations are notoriously difficult to spot, often described as clinically and radiographically occult. In fact, misses are so common, they could be called, colloquially, the standard of care. Not that they have to be, however.

Manickam “Nicks” Kumaravel, team doctor for the NFL’s Houston Texans, highlighted why posterior dislocations remain so frequently missed in chest and shoulder trauma during his ARRS Annual Meeting lecture.

Glow On! On a standard AP view, look for the classic light bulb appearance of the humeral head. If a post-fall image simply doesn’t look right, voilà, that’s your cue to dig deeper.

N.B. You cannot rely on a single projection…

• Scapular Y view is the critical orthogonal projection.
• It clearly demonstrates the posterior displacement that AP can hide.

RadFYI: To avoid a miss, maintain a high index of suspicion, always verifying with orthogonal views.

Fournier’s gangrene is a rapidly progressing polymicrobial necrotizing fasciitis of the perineal, perianal, and genital regions. Because of its high mortality rate, immediate diagnosis and intervention are non-negotiable.

As illustrated by Paul Nikolaidis, MD, during the ARRS Online Course Imaging of Pathologies of Male External Genitalia, this surgical emergency typically affects middle-aged men—particularly those with risk factors like diabetes, indwelling catheters, recent surgery, or immunosuppression from cancer treatments.

• Down & Dirty? Look for dirty shadowing or ring-down artifacts caused by gas within the soft tissues, along with significant skin thickening.
• Notable Normality: The testes, themselves, usually appear normal, as the infection follows fascial planes, rather than involving the scrotal contents directly.
• Gold Map: CT comes in clutch in the ED to confirm the diagnosis and, more importantly, to show the extent of involvement for the surgical team.

Whereas imaging is vital, roughly 10% of patients will not show visible gas on initial scans; therefore, clinical suspicion must remain high (even if those classic dirty shadows are absent).

RadFYI: Early diagnosis is the only way to ensure survival. Once identified, management must include aggressive antibiotic therapy and immediate surgical debridement of all affected areas.

A 43-year-old patient in Rochester, MN, presented to Mayo Clinic’s Ceylan Colak, MD, with complex hand trauma following a snowblower accident. While multiple phalangeal fractures were immediately apparent, as Dr. Colak recounted during the ARRS Online Course Imaging of Small Joints: A Review for Clinical Practice, a comminuted thumb fracture was initially overlooked due to the severity of the patient’s way more overt injuries.

Distal Distraction: Distal phalangeal and tuft fractures are not just common; they account for nearly 50% of all hand fractures. In the setting of high-energy trauma—vis-à-vis a southeastern Minnesota snowblower injury—rads can easily fall victim to “satisfaction of search,” missing these small yet clinically significant injuries:

• Initial Findings: Multiple displaced and non-displaced phalangeal fractures.
• All Thumb: A comminuted, minimally displaced fracture of the thumb distal phalanx.
• Call Kirschner: The patient ultimately required K-wire placement for stabilization of the multiple hand fractures.

Bottom Line: When assessing a bad hand fracture, always perform a systematic check of each and every digit. Don’t let the most dramatic injuries distract you from the tuft; it’s where half of hand fractures happen.

AI-powered automation is moving upstream, shifting the focus from just lesion detection to the very beginning of the imaging process: acquisition and post-processing. Most imaging costs are tied to these upstream tasks. By automating them, Linda Moy, MD, explained at ARRS 2026, providers can improve image quality while simultaneously lowering costs and increasing operational efficiency…

• On the DL: Deep learning (DL) reconstruction tools allow for noisier or lower-resolution initial imaging that AI then transforms into high-quality images. DL algos can reduce MRI scan times by >50%—while maintaining, or even improving, diagnostic quality.
• Keep the Noise Down: AI denoising algorithms have demonstrated a 60% reduction in radiation dose, alongside a 39% reduction in image noise.
• Table for 3D? Using three-dimensional ceiling cameras and infrared imaging to automate table height and positioning can save 32 seconds per exam, as well as reduce radiation dose by some 20%.
• No Contrast: Synthetic AI images can now simulate contrast-enhanced MRI, without actual contrast agents. This is a breakthrough for pregnant patients, those with severely impaired renal function, or populations concerned about gadolinium deposition.

These advancements significantly improve the patient experience, particularly for peds patients who may no longer require sedation, and claustrophobic patients who benefit from shorter time in the scanner.

Mind the Mirage: Rads must remain vigilant regarding AI “hallucinations.” While rare, these tools can occasionally invent lesions that do not exist or remove true lesions during the reconstruction process.

Bottom Line: AI reconstruction works seamlessly in the background to provide higher signal-to-noise ratios and reduced artifacts, allowing rads to focus on downstream diagnostic tasks with better data in less time.

When rads encounter symmetric macroscopic fat in the perirenal space, the initial instinct is often to fear well-differentiated liposarcoma or lymphoma. Distinguishing these from benign extra-adrenal perirenal myelipoma is critical to avoiding unnecessary clinical anxiety and aggressive surgical intervention.

Impressive Abs! In this excerpt from the ARRS 2026 Challenging Abdominal Cases Instructional Course, Cooky Menias, MD, presents a patient with abdominal bloating who revealed a symmetric retroperitoneal process pressing on the kidneys. Despite the lack of subcutaneous fat, the patient exhibited significant intra-abdominal fat that really impressed on the renal parenchyma.

The Diagnosis:

• Extra-adrenal myelipoma is a rare, benign mesenchymal tumor composed of fat and hematopoietic cells.
• They typically appear in the 5th to 6th decades of life.
• The most common extra-adrenal locations are the perirenal and presacral spaces.

The Pearls:

• Fat Chance: Unlike perirenal fibrosis (IgG4-related disease) or Erdheim-Chester, which encase the kidneys and lack fat, myelipomas contain macroscopic fat and embed (i.e., “impress”) upon the renal tissue.
• PET-CT Utility? While not diagnostic, PET-CT can be reassuring by showing a lack of significant uptake, helping to rule out high-grade lymphoma or aggressive malignancy.
• Stress Test: These tumors may arise from ectopic adrenal tissue or reticular endothelial cells that become exuberant during chronic stress, endocrine dysfunction, or inflammation.

Bottom Line: If you see symmetric macroscopic fat embedding the kidneys in an older patient with low metabolic activity on PET, think extra-adrenal myelipoma. While biopsy (even open biopsy) may be required for definitive comfort, recognizing this embedding fat pattern can narrow the differential significantly.

A landmark California Court of Appeal decision is shielding out-of-state remote professionals from Golden State taxation. In Garcia-Rojas v. California Franchise Tax Board, the court ruled that a Texas teleradiologist is not subject to California income tax, despite serving California patients.

So, California attempted to use a complex corporate tax theory to claim income from a contractor who never physically entered the state.

• The Provider: Dr. Xavier Garcia-Rojas, a Texas-based radiologist, performed contract reads for San Diego-based StatRad from 2018 to 2020.
• The Dispute: The Franchise Tax Board (FTB) claimed Dr. Garcia-Rojas owed taxes because he used StatRad’s software, was licensed in California, and served Cali patients.
• The Numbers: The doctor originally paid roughly $48,000 in taxes, penalties, and interest under protest before suing for a refund.

Legal Pivot: The court rejected FTB’s attempt to apply the unitary business doctrine (usually reserved for multi-state corporations) to a single-person sole proprietorship.

• The Rule: A nonresident providing remote professional services does not automatically become part of a unitary business just because their client is in California.
• The Result: Because the actual labor (i.e., image interpretation) happened at a desk in Texas, the income is not California-sourced.

As Bloomberg noted, Garcia-Rojas v. CAFTB sets a binding precedent for thousands of remotely contracted lawyers and consultants, as well as the surfeit of tech sector labor, working for California firms. Indeed, it confirms that location of labor—not the location of the client—is the deciding factor for individual income sourcing.

The “football sign” is a pathognomonic indicator of massive pneumoperitoneum on supine abdominal radiographs, characterized by a large, oval radiolucent area shaped like an American football.

SIP: In extremely low birth weight infants, this finding often signals spontaneous intestinal perforation (SIP), a condition distinct from necrotizing enterocolitis (NEC). Recognizing the difference is critical because SIP is often an isolated vascular insult, and as Susan D. John, MD, illustrated during Mastering Radiology: A Comprehensive Board Review for Residents and Refresher for Radiologists in Practice, some cases may heal without surgical intervention.

Three Tips from Dr. John:

1. Radiolucent Oval—Massive free air collects anterior to the abdominal viscera, distending the peritoneal cavity and creating a sharp interface with the parietal peritoneum.
2. Laces Out—The air outlines longitudinal structures of the anterior abdominal wall, most commonly the falciform ligament in the right upper abdomen. It may also outline the median umbilical ligament (urachal vestige) or medial umbilical ligaments (umbilical arteries).
3. Bowel Appearance—A key clue for SIP is that the bowel often appears normal in caliber without evidence of pneumatosis intestinalis, which would typically be present in NEC.

Bottom Line: While frequently associated with spontaneous perforation in premature infants (ca. 24 weeks gestation), the football sign can also be seen in cases of iatrogenic trauma, such as rectal perforation resulting from the placement of a rectal tube. If the sign is suspected on a supine film, a decubitus view can be used to confirm the presence of free air.

Distinguishing between oligodendroglioma and IDH-mutant astrocytoma is a high-yield challenge for neurorads, as both typically present as infiltrative, T2-hyperintense masses with variable enhancement.

1p/19q: While both tumors fall under the umbrella of IDH-mutant adult gliomas, their molecular signatures—and, consequently, imaging phenotypes—offer specific smoking guns for diagnosis.

• Oligodendroglioma: Defined by IDH mutation and 1p/19q codeletion.
• Astrocytoma: IDH-mutant but 1p/19q intact.

As part of the dynamic, rapid-fire Neuroradiology Case Review during the 2026 ARRS Annual Meeting, Susana Calle, MD, pointed out some key discriminators…

T2-FLAIR Mismatch: This is the strongest predictor for IDH-mutant astrocytoma, boasting a specificity of 90–100%.

• The lesion shows homogeneous high signal on T2-weighted images but complete or near-complete signal suppression on T2-FLAIR.
• The presence of this sign virtually rules out oligodendroglioma (although its absence does not exclude an astrocytoma diagnosis).

Worm-like: If you see gyroform cortical calcifications, think oligodendroglioma.

• Calcification occurs in up to 90% of oligodendrogliomas.
• These tumors have a strong frontal lobe predominance and tend to be more cortically based than astrocytomas.
• Astrocytomas are far less likely to calcify.

Perfusion Paradox: Typically, high cerebral blood volume (CBV) indicates high-grade malignancy, but oligodendrogliomas are the exception.

• Elevated CBV is often seen in oligodendrogliomas, regardless of grade, due to their characteristic “chicken-wire” fine intratumoral capillaries, rather than true neoangiogenesis.

Bottom Line: Calcified cortical tumor in the frontal lobe? Sway toward oligodendroglioma. T2-FLAIR mismatch sign identified? Think IDH-mutant astrocytoma. Accurate noninvasive identification of these genotypes is critical because 1p/19q codeletion in oligodendrogliomas is associated with a better response to chemoradiation and significantly improved overall survival.

For patients with severe aortic stenosis and a life expectancy greater than one year, the choice between transcatheter aortic valve replacement (TAVR) and surgical aortic valve replacement (SAVR) is a complex decision made by a multidisciplinary heart team.

Three Things: Although TAVR was initially the standard for patients with high surgical risk, its use is rapidly increasing. Today, TAVR’s approved for low-risk patients, too. However, as noted by Matthew Stib, MD, of Mayo Clinic Arizona during the ARRS Online Course Mastering CT for TAVR and TMVR, the choice still hinges on three primary features: age, surgical risk, and life expectancy.

• <65 years: SAVR is preferable. Surgical valves have established longevity, whereas TAVR has only been in use for about a decade, and its long-term durability is less certain.
• 65–80 years: Both are viable options; the choice depends on patient preference and specific clinical or anatomical factors.
• >80 years: TAVR is the preferred approach.
• High Surgical Risk: TAVR is favored, regardless of age.

Two Tips: Pre-procedural CT remains the reference standard for TAVR planning, serving two critical roles: sizing the prosthesis at the aortic root and evaluating vascular access in the thorax, abdomen, and pelvis.

Beyond the Valve: Recent research indicates that rads should look at more than just the valve to predict patient outcomes. Features of right heart failure identified on pre-procedure CT are independent predictors of 1-year mortality after TAVR:

• Pulmonary Artery Dilation: A median main size of 3.2 cm was associated with death within 1 year, compared to 2.9 cm in survivors.
• Pericardial Effusion: The presence of a moderate-to-large pericardial effusion is a strong predictor of mortality, even when adjusting for the Society of Thoracic Surgeons clinical risk score.

Bottom Line: As TAVR becomes more common, the rad’s role is expanding from procedural planning to risk stratification. Identifying signs of right heart failure—like a dilated PA or pericardial effusion—can help identify high-risk candidates who may have poor outcomes, despite a technically successful procedure.

In small capacity joints, septic arthritis doesn’t stay contained—it bursts! Apropos, William Morrison, MD, of Thomas Jefferson University Hospital coined a very specific, Saturday Night Live-forward metaphor to help rads recognize the larger-than-life presentation of infection in tiny spaces.

The Chris Farley Finding: Just as the late physical comedy genius would don one-size-too-small outfits to accentuate his larger frame, septic arthritis in small joints creates an angry effusion that so often appears too big for its britches.

• The Mechanism: Because joints like the fingers, sternoclavicular, or sacroiliac (SI) have very small capacities, infection pops out of the capsule early on.
• The Look: Imaging reveals massive periarticular edema and enhancement disproportionate to the joint size.

Holy Schnikes! As Dr. Morrison described in MSK Infection Update: What Do I Need to Say and Do?, recognizing this bursting effect is critical for early diagnosis, especially in the sacroiliac joint.

• The Great Imitator: Septic sacroiliitis often presents as sciatica because the inflammation irritates the sciatic nerve sitting directly in the sciatic notch.
• The Diagnostic Trap: Clinicians may mistake the pain for a disc herniation and order a lumbar spine MRI.
• The Rad’s Role: Looking all the way to the edge of the image for SI joint edema, you may be the first to catch the infection.

Bottom Line: Beyond the Chris Farley finding, you’ll also want to watch for three more classic signs of septic arthritis in small joints:

• Erosions: Destruction of the joint surface.
• Loss of subchondral white line: A key indicator of joint space infection.
• Disproportionate soft-tissue involvement: Massive edema surrounding a tiny joint.

No, it’s not yet another template. ACR’s Neck Imaging Reporting and Data System (NI-RADS) is really about a strategic sales pitch and local adaptation. Paul Bunch, MD, ACR NI-RADS Committee Chair, explained to AJR Neuroradiology Imaging Senior Editor Carlos Zamora, MD, PhD, in this Video Article how he successfully integrated NI-RADS MRI version 2025 recommendations at Wake Forest by focusing on clinical buy-in and implementation science.

How Concerned Are You? Standardized reporting like NI-RADS MRI v2025 eliminates ambiguity. Before implementation, tumor boards often struggled with reports where the rad’s level of concern was unclear. Post-implementation, 100% of surveyed referring physicians agreed that the numeric scoring system was valuable for patient management.

Steps for Success: Dr. Bunch followed a four-point roadmap to move NI-RADS from a white paper to daily clinical practice:

1. ID Your Champs—The push at Wake Forest actually began with a request from clinical colleagues at multidisciplinary tumor boards who saw the potential benefit.
2. Pitch Perfect—Dr. Bunch presented to his neuro group, framing NI-RADS not as a radical change to their interpretation skills, but as a tool for uniform communication.
3. 90 Days—The department ran an optional 3-month trial, using surveys and data mining to track usage and satisfaction alike among both rads and referring doctors.
4. Adaptation & Context—Following principles of implementation science, the team kept the core identity of NI-RADS (e.g., suspicion levels and linked recommendations), while modifying peripheral details to fit local needs. 

Local Mods: Dr. Bunch was quick to note that rigid adherence can hinder adoption. To gain full buy-in, his colleagues made two key adjustments:

1. Flexible Follow-Up: They removed that 3-month timeframe for short-interval follow-up to prevent insurance authorization issues and allow clinicians more flexibility.
2. Worst-First Lead: To ensure referring MDs didn’t stop reading after a NI-RADS 1 primary site score, Bunch et al. added an overall assessment score at the top of the report reflecting the most concerning finding in the entire study.

Bottom Line: By treating implementation as a collaborative effort rather than a top-down mandate, Dr. Bunch’s team turned NI-RADS into a templated tool that virtually eliminated “how worried are you?” questions during tumor boards.