Publications

PURPOSE: To minimize the sensitivity of inhomogeneous magnetization transfer gradient-echo (ihMT-GRE) imaging to radiofrequency (RF) transmit field ( B1+ ) inhomogeneities at 3 T.

METHODS: The ihMT-GRE sequence was optimized by varying the concentration of the RF saturation energy over time, obtained by increasing the saturation pulse power while extending the sequence repetition time (TR). Different protocols were tested using numerical simulations and human in vivo experiments in the brain white matter (WM) of healthy subjects at 3 T. The sensitivity of the ihMT ratio (ihMTR) to B1+ variations was investigated by comparing measurements obtained at nominal transmitter adjustments and following a 20% global B1+ drop. The resulting relative variations (δihMTR ) were evaluated voxelwise as a function of the local B1+ distribution. The reproducibility of the protocol providing minimal B1+ bias was assessed in a test-retest experiment.

RESULTS: In line with simulations, ihMT-GRE experiments conducted at high concentration of the RF energy over time demonstrated strong reduction of the B1+ inhomogeneity effects in the human WM. Under the optimal conditions of 350-ms TR and 3-µT root mean square (RMS) saturation power, 73% of all WM voxels presented δihMTR below 10%. Reproducibility analysis yielded a close-to-zero systematic bias (ΔihMTR = -0.081%) and a high correlation (ρ² = 0.977) between test and retest experiments.

CONCLUSION: Concentrating RF saturation energy in ihMT-GRE sequences mitigates the sensitivity of the ihMTR to B1+ variations and allows for clinical-ready ihMT imaging at 3 T. This feature is of particular interest for high and ultra-high field applications.

OBJECTIVE: During COVID-19, Harvard Medical School pivoted to online learning. A large student cohort took a completely virtual Radiology clerkship with daily programming including virtual small group teaching sessions or "homerooms."

MATERIALS AND METHODS: One hundred and eleven medical students were divided into 12 virtual small group sessions which emphasized foundational concepts. Uniform teaching materials were used across all homerooms in order to deepen understanding and allow insight into the working methods of radiologists. Students evaluated the homeroom learning and teachers for utility and benefit to their educational experience.

RESULTS: Most students (93%) felt the homerooms provided an educational benefit and reinforced topics studied (77%). Most students (84%) felt the leaders created an environment conducive to learning. Despite being virtual, students were able to form interpersonal connections with the homeroom leaders.

CONCLUSIONS: Incorporating virtual small group learning can be a valuable component of a virtual or hybrid Radiology clerkship, solidifying foundational concepts with the homeroom leaders playing a major role. While developed by necessity due to COVID-19, virtual small group learning with engaged leaders is an educational strategy whose benefit can continue even as there is return to in-person learning.

A standardized guideline and scoring system should be used for the MR imaging diagnosis of peripheral neuropathy. The MR imaging-based Neuropathy Score Reporting and Data System (NS-RADS) is a newly devised classification system (in press in AJR) that can be used to communicate both type and severity of peripheral neuropathy in the light of clinical history and examination findings. The spectrum of neuropathic conditions and peripheral nerve disorders covered in this system includes nerve injury, entrapment, neoplasm, diffuse neuropathy, and post-interventional states. This classification system also describes the temporal MR imaging appearances of regional muscle denervation changes. This review article is based on the multicenter validation study pre-published in American journal of Roentgenology and discusses technical considerations of optimal MR imaging for peripheral nerve evaluation and discusses the NS-RADS classification and its severity scales with illustration of conditions that fall under each classification. The readers can gain knowledge of the NS-RADS classification system and learn to apply it in their practices for improved inter-disciplinary communications and timely patient management.

PURPOSE: To determine institutional practice requirements for personal protective equipment (PPE) in cross-sectional interventional radiology (CSIR) procedures among a variety of radiology practices in the USA and Canada.

METHODS: Members of the Society of Abdominal Radiology (SAR) CSIR Emerging Technology Commission (ETC) were sent an eight-question survey about what PPE they were required to use during common CSIR procedures: paracentesis, thoracentesis, thyroid fine needle aspiration (FNA), superficial lymph node biopsy, deep lymph node biopsy, solid organ biopsy, and ablation. Types of PPE evaluated were sterile gloves, surgical masks, gowns, surgical hats, eye shields, foot covers, and scrubs.

RESULTS: 26/38 surveys were completed by respondents at 20/22 (91%) institutions. The most common PPE was sterile gloves, required by 20/20 (100%) institutions for every procedure. The second most common PPE was masks, required by 14/20 (70%) institutions for superficial and deep procedures and 12/12 (100%) institutions for ablation. Scrubs, sterile gowns, eye shields, and surgical hats were required at nearly all institutions for ablation, whereas approximately half of institutions required their use for deep lymph node and solid organ biopsy. Compared with other types of PPE, required mask and eye shield use showed the greatest increase during the SARS-CoV-2 pandemic.

CONCLUSION: PPE use during common cross-sectional procedures is widely variable. Given the environmental and financial impact and lack of consensus practice, further studies examining the appropriate level of PPE are needed.

Background Emotional harm incidents in health care may result in lost trust and adverse outcomes. However, investigations of emotional harm in radiology departments remain lacking. Purpose To better understand contributors and clinical scenarios in which emotional harm can occur in radiology, to document incidences, and to develop preventative countermeasures. Materials and Methods A large tertiary hospital adverse event reporting system was retrospectively searched for submissions under the category of dignity and respect in radiology between December 2014 and December 2020. Submissions were assigned to one of 14 categories per a previously developed classification system. Root-cause analysis of events was performed with a focus on countermeasures for future prevention. The person experiencing emotional harm (patient or staff) was noted. Results Of all radiology-related submissions, 37 of 3032 (1.2%) identified 43 dignity and respect incidents: failure to be patient centered (n = 23; 54%), disrespectful communication (n = 16; 37%), privacy violation (n = 2; 5%), minimization of patient concerns (n = 1; 2%), and loss of property (n = 1; 2%). Failure to be patient centered (n = 23) was subcategorized into disregard for patient preference (12 of 23; 52%), delay in care (eight of 23; 35%), and ineffective communication (three of 23; 13%). Of the 43 incidents, 32 involved patients (74%) and 11 involved staff (26%). Emotional harm in staff was because of disrespectful communication from other staff (eight of 11; 73%). Seventy-three countermeasures were identified: staff communication training (n = 32; 44%), individual feedback (n = 18; 25%), system innovation (n = 16; 22%), improvement of existing communication processes (n = 3; 4%), process reminders (n = 3; 4%), and unclear (n = 1; 1%). Individual feedback and staff communication training that focused on active listening, asking for the patient's preferences, and closed-loop communication addressed 34 of the 43 incidents (79%). Conclusion Most emotional harm incidents were from disrespectful communication and failure to be patient centered. Providing training focused on active listening, asking for patient's preferences, and closed-loop communication would potentially prevent most of these incidents. © RSNA, 2021 See also the editorial by Bruno in this issue.

Mucin-producing neoplasms in the abdomen and pelvis are a distinct entity, separate from simple fluid-containing neoplasms and loculated fluid collections. Mucin is a thick gelatinous substance and-owing to its high water content-has imaging features that can be mistaken for those of simple fluid-containing neoplasms with multiple imaging modalities. However, mucin-producing neoplasms arise from specific organs in the abdomen and pelvis, with unique imaging appearances, knowledge of which is important to guide accurate diagnosis and management. With its large field of view and high soft-tissue resolution, MRI has advantages over other imaging modalities in characterizing these neoplasms. The authors focus on the spectrum of MRI features of such mucin-producing neoplasms and illustrate how-despite a varied organ origin-some of these neoplasms share similar MRI and histopathologic features, thereby helping narrow the differential diagnosis. One common finding in these tumors is that the presence of internal complexity and solid enhancing components increases as the degree of malignant transformation increases. Lack of internal complexity generally indicates benignity. These tumors have a varied range of prognosis; for example, a low-grade appendiceal mucinous neoplasm is indicative of a good prognosis, while a mucinous tumor of the rectum is known to manifest at an early age with aggressive behavior and poorer prognosis compared with its nonmucinous counterpart. Online supplemental material is available for this article. ©RSNA, 2022.