Spectral power ratio as a measure of EEG changes in mild cognitive impairment due to Alzheimer's disease: a case-control study.

Adopting preventive strategies in individuals with subclinical Alzheimer's disease (AD) has the potential to delay dementia onset and reduce healthcare costs. Thus, it is extremely important to identify inexpensive, scalable, sensitive, and specific markers to track disease progression. The electroencephalography spectral power ratio (SPR: the fast to slow spectral power ratio), a measure of the shift in power distribution from higher to lower frequencies, holds potential for aiding clinical practice. The SPR is altered in patients with AD, correlates with cognitive functions, and can be easily implemented in clinical settings. However, whether the SPR is sensitive to pathophysiological changes in the prodromal stage of AD is unclear. We explored the SPR of individuals diagnosed with amyloid-positive amnestic mild cognitive impairment (Aß+aMCI) and its association with both cognitive function and amyloid load. The SPR was lower in Aß+aMCI than in the cognitively unimpaired individuals and correlated with executive function scores but not with amyloid load. Hypothesis-generating analyses suggested that aMCI participants with a lower SPR had an increased probability of a positive amyloid positron emission tomography. Future research may explore the potential of this measure to classify aMCI individuals according to their AD biomarker status.

Summary: Appropriate Use Criteria for Lymphoscintigraphy in Sentinel Node Mapping and Lymphedema/Lipedema.

Expert representatives from 11 professional societies, as part of an autonomous work group, researched and developed appropriate use criteria (AUC) for lymphoscintigraphy in sentinel lymph node mapping and lymphedema. The complete findings and discussions of the work group, including example clinical scenarios, were published on October 8, 2022, and are available at https://www.snmmi.org/ClinicalPractice/content.aspx?ItemNumber=42021 The complete AUC document includes clinical scenarios for scintigraphy in patients with breast, cutaneous, and other cancers, as well as for mapping lymphatic flow in lymphedema. Pediatric considerations are addressed. These AUC are intended to assist health care practitioners considering lymphoscintigraphy. Presented here is a brief overview of the AUC, including the rationale and methodology behind development of the document. For detailed findings of the work group, the reader should refer to the complete AUC document online.

Delayed hospital discharges and the trolley crisis.

We audited use of acute hospital beds in Connolly Hospital over a 3-month period (January-March 2020) which coincided with increased provision of step-down (nursing home) beds. Our results show both ineffective and inefficient baseline uses of these acute beds. Increased step-down beds improve patient care by reducing the trolley count, shortening average length of stay and reducing waiting lists. These data confirm that more step-down beds are a high priority for our Health Service to improve the effectiveness and efficiency of our hospitals i.e. better care at less cost.

Superficial and functional imaging of the tricipital lymphatic pathway: a modern reintroduction.

PURPOSE: The tricipital, or Caplan's, lymphatic pathway has been previously identified in cadavers and described as a potential compensatory pathway for lymphatic drainage of the upper extremity, as it may drain lymphatic fluid directly to the scapular lymph nodes, avoiding the axillary lymph node groups. The aim of this study was to map the anatomy of the tricipital pathway in vivo in patients without lymphatic disease. METHODS: A retrospective review was performed to identify patients with unilateral breast cancer undergoing preoperative Indocyanine green (ICG) lymphography prior to axillary lymph node dissection from May 2021 through January 2022. Exclusion criteria were evidence or known history of upper extremity lymphedema or non-linear channels visualized on ICG. Demographic, oncologic, and ICG imaging data were extracted from a Lymphatic Surgery Database. The primary outcome of this study was the presence and absence of the tricipital pathway. The secondary outcome was major anatomical variations among those with a tricipital pathway. RESULTS: Thirty patients underwent preoperative ICG lymphography in the study period. The tricipital pathway was visualized in the posterior upper arm in 90% of patients. In 63% of patients, the pathway had a functional connection to the forearm (long bundle variant) and in 27%, the pathway was isolated to the upper arm without a connection to the forearm (short bundle variant). In those with a long bundle, the contribution was predominantly from the posterior ulnar lymphosome. Anatomic destinations of the tricipital pathway included the deltotricipital groove and the medial upper arm channel, which drains to the axilla. CONCLUSION: When present, the tricipital pathway coursed along the posterior upper arm with variability in its connections to the forearm distally, and the torso proximally. Long-term follow-up studies will help determine the significance of these anatomic variations in terms of individual risk of lymphedema after axillary nodal dissection.

A Single Institution Multi-disciplinary Approach to Power-assisted Liposuction for the Management of Lymphedema.

OBJECTIVE: To implement and evaluate outcomes from a comprehensive, multi-disciplinary debulking program in the United States. SUMMARY OF BACKGROUND DATA: Interest in and access to surgical treatment for chronic lymphedema (LE) in the United States have increased in recent years, yet there remains little attention on liposuction, or debulking, as an effective treatment option. In some other countries, debulking is a common procedure for the surgical treatment of LE, is covered by insurance, and has demonstrated excellent, reproducible outcomes. In this study we describe our experience implementing a debulking technique from Sweden in the United States. METHODS: Patients who presented with chronic LE followed a systematic multi-disciplinary work-up. For debulking with power assisted liposuction, the surgical protocol was modeled after that developed by Håkan Brorson. A retrospective review of consecutive patients who underwent debulking at our institution was conducted. RESULTS: Between December 2017 and January 2020, 39 patients underwent 41 debulking procedures with power assisted liposuction, including 23 upper and 18 lower extremities. Mean patient age was 58 years and 85% of patients had LE secondary to cancer, the majority of which (64%) was breast cancer. Patients experienced excess volume reductions of 116% and 115% in the upper and lower extremities, respectively, at 1 year postoperatively. Overall quality of life (LYMQOL) improved by a mean of 33%. Finally, patients reported a decreased incidence of cellulitis and decreased reliance on conservative therapy modalities postoperatively. CONCLUSIONS: Debulking with power assisted liposuction is an effective treatment for patients with chronic extremity LE. The operation addresses patient goals and improves quality of life, and additionally reduces extremity volumes, infection rates and reliance on outpatient therapy. A comprehensive, multi-disciplinary debulking program can be successfully implemented in the United States healthcare system.

Impact of multisession 40Hz tACS on hippocampal perfusion in patients with Alzheimer's disease.

BACKGROUND: Alzheimer's disease (AD) is associated with alterations in cortical perfusion that correlate with cognitive impairment. Recently, neural activity in the gamma band has been identified as a driver of arteriolar vasomotion while, on the other hand, gamma activity induction on preclinical models of AD has been shown to promote protein clearance and cognitive protection. METHODS: In two open-label studies, we assessed the possibility to modulate cerebral perfusion in 15 mild to moderate AD participants via 40Hz (gamma) transcranial alternating current stimulation (tACS) administered 1 h daily for 2 or 4 weeks, primarily targeting the temporal lobe. Perfusion-sensitive MRI scans were acquired at baseline and right after the intervention, along with electrophysiological recording and cognitive assessments. RESULTS: No serious adverse effects were reported by any of the participants. Arterial spin labeling MRI revealed a significant increase in blood perfusion in the bilateral temporal lobes after the tACS treatment. Moreover, perfusion changes displayed a positive correlation with changes in episodic memory and spectral power changes in the gamma band. CONCLUSIONS: Results suggest 40Hz tACS should be further investigated in larger placebo-controlled trials as a safe, non-invasive countermeasure to increase fast brain oscillatory activity and increase perfusion in critical brain areas in AD patients. TRIAL REGISTRATION: Studies were registered separately on ClinicalTrials.gov ( NCT03290326 , registered on September 21, 2017; NCT03412604 , registered on January 26, 2018).

Use of non-contrast MR in diagnosing secondary lymphedema of the upper extremities.

PURPOSE: The purpose of the study is to determine if a combination of dermal thickening and subcutaneous fluid honeycombing on non-contrast MRI, termed the dermal rim sign (DRS), can be diagnostically analogous to dermal backflow seen on lymphoscintigraphy in patients with secondary upper extremity lymphedema. MATERIALS AND METHODS: Upper extremity MRI and lymphoscintigraphy were performed on patients referred to a multidisciplinary lymphedema clinic for suspicion of secondary lymphedema. Sensitivity, specificity, and positive and negative predictive values of DRS on MRI in detecting dermal backflow on lymphoscintigraphy and the correlation between DRS, Indocyanine Green (ICG) lymphography, bioimpedence L-Dex® ratio and MRI Lymphedema Staging were calculated. Weighted interobserver agreements on the presence and location of DRS on MRI were calculated. RESULTS: Of the 45 patients in the study, 91.1% (41/45) of patients had history of breast cancer. The average age was 58.4 ± 10.5 years, with a mean symptom duration of 4.7 ± 4.4 years. The mean BMI was 30.5 ± 7.0 kg/m2. Interobserver agreement on the presence and the extent of DRS on MRI was 0.93 [95% confidence-interval: 0.80-1]. DRS was present in 97% (32/33) of patients who demonstrated dermal backflow on lymphoscintigraphy. Sensitivity, specificity, PPV, and NPV of DRS were 96.6% [81.7%-99.9%], and 75.0% [47.6%-92.7%], 87.5% [74.9%-94.3%], and 92.3% [63.1%-98.8%]. DRS was associated with severity on ICG lymphography and bioimpedance (both p < 0.001). CONCLUSIONS: DRS on non-contrast MRI is highly predictive of dermal backflow and correlates with clinical measures of lymphedema severity. DRS may be used as an independent diagnostic biomarker to identify patients who would benefit from dedicated exams.

LTP-like plasticity is impaired in amyloid-positive amnestic MCI but independent of PET-amyloid burden.

Transcranial magnetic stimulation (TMS) reveals decreased efficacy of long-term potentiation-like (LTP-like) neuroplastic mechanisms in Alzheimer's disease (AD). However, it is not yet known whether LTP-like plasticity is also impaired in prodromal AD, or how abnormal TMS measures are related to established AD biomarkers. Here, we investigated the LTP-like response to intermittent theta-burst stimulation in 17 amyloid-positive participants with amnestic mild cognitive impairment (MCI) and 10 cognitively unimpaired controls. Our results showed a lack of LTP-like neuromodulation in MCI compared with controls that was unrelated to quantitative amyloid-beta burden on positron emission tomography. Surprisingly, greater LTP-like response was related to worse memory function in the MCI group, highlighting the complex role of neuroplasticity in the prodromal stages of AD. Overall, our results demonstrate abnormal LTP-like plasticity using intermittent theta-burst stimulation assessment in amyloid-positive participants with MCI. These findings support the potential for development of TMS measures as prognostic markers or therapeutic targets in early-stage symptomatic AD.

MRI staging of upper extremity secondary lymphedema: correlation with clinical measurements.

OBJECTIVES: Staging of upper extremity lymphedema is needed to guide surgical management, but is not standardized due to lack of accessible, quantitative, or precise measures. Here, we established an MRI-based staging system for lymphedema and validate it against existing clinical measures. METHODS: Bilateral upper extremity MRI and lymphoscintigraphy were performed on 45 patients with unilateral secondary lymphedema, due to surgical intervention, who were referred to our multidisciplinary lymphedema clinic between March 2017 and October 2018. MRI short-tau inversion recovery (STIR) images were retrospectively reviewed. A grading system was established based on the cross-sectional circumferential extent of subcutaneous fluid infiltration at three locations, labeled MRI stage 0-3, and was compared to L-Dex®, ICG lymphography, volume, lymphedema quality of life (LYMQOL), International Society of Lymphology (ISL) stage, and lymphoscintigraphy. Linear weighted Cohen's kappa was calculated to compare MRI staging by two readers. RESULTS: STIR images on MRI revealed a predictable pattern of fluid infiltration centered on the elbow and extending along the posterior aspect of the upper arm and the ulnar side of the forearm. Patients with higher MRI stage were more likely to be in ISL stage 2 (p = 0.002) or to demonstrate dermal backflow on lymphoscintigraphy (p = 0.0002). No correlation was found between MRI stages and LYMQOL. Higher MRI stage correlated with abnormal ICG lymphography pattern (rs = 0.63, p < 0.0001), larger % difference in limb volume (rs = 0.68, p < 0.0001), and higher L-Dex® ratio (rs = 0.84, p < 0.0001). Cohen's kappa was 0.92 (95% CI, 0.85-1.00). CONCLUSION: An MRI staging system for upper extremity lymphedema offers an improved non-invasive precision marker for lymphedema for therapeutic planning. KEY POINTS: • Diagnosis and staging of patients with secondary upper extremity lymphedema may be performed with non-contrast MRI, which is non-invasive and more readily accessible compared to lymphoscintigraphy and evaluation by lymphedema specialists. • MRI-based staging of secondary upper extremity lymphedema is highly reproducible and could be used for long-term follow-up of patients. • In patients with borderline clinical measurements, MRI can be used to identify patients with early-stage lymphedema.

Developing a Lymphatic Surgery Program: A First-Year Review.

BACKGROUND: Lymphedema is a chronic condition that carries a significant physical, psychosocial, and economic burden. The authors' program was established in 2017 with the aims of providing immediate lymphatic reconstruction in high-risk patients undergoing lymphadenectomy and performing delayed lymphatic reconstruction in patients with chronic lymphedema. The purpose of this study was to describe the authors' clinical experience in the first year. METHODS: A retrospective review of our clinical database was performed on all individuals presenting to the authors' institution for lymphatic surgery consideration. Patient demographics, clinical characteristics, and surgical management were reviewed. RESULTS: A total of 142 patients presented for lymphatic surgery evaluation. Patients had a mean age of 54.8 years and an average body mass index of 30.4 kg/m. Patients with lymphedema were more likely to be referred from an outside facility compared to patients seeking immediate lymphatic reconstruction (p < 0.001). For patients with lymphedema, the most common cause was breast cancer related. Thirty-two percent of all patients evaluated underwent a lymphatic procedure. Of these, 32 were immediate lymphatic reconstructions and 13 were delayed lymphatic reconstructions. In the authors' first year, 94 percent of eligible patients presenting for immediate lymphatic reconstruction underwent an intervention versus only 38 percent of eligible lymphedema patients presenting for delayed lymphatic reconstruction (p < 0.001). CONCLUSIONS: First-year review of our lymphatic surgery experience has demonstrated clinical need evidenced by the number of patients and high percentage of outside referrals. As a program develops, lymphatic surgeons should expect to perform more time-sensitive immediate lymphatic reconstructions, as evaluation of chronic lymphedema requires development of a robust team for workup and review.

Society of Nuclear Medicine and Molecular Imaging Efforts Toward Standardization: From Procedure Standards to Appropriate Use Criteria.

The Society of Nuclear Medicine and Molecular Imaging (SNMMI) continues to develop clinical guidance documents to synthesize and disseminate clinical information for optimal patient care. Clinical guidelines help standardize delivery of care and improve quality. Chronology of SNMMI efforts in the development of nuclear medicine procedure standards (PS) and appropriate use criteria (AUC) is reviewed. Historically, the Society has focused its efforts on developing PS describing the accepted methodology for performing nuclear medicine procedures. However, legislative mandates and lack of existing evidence-based documents prompted SNMMI to take a lead in developing AUC for high-value nuclear medicine procedures. AUC presents common clinical scenarios where the use of nuclear medicine procedures is or is not appropriate. Methodology used by SNMMI for the development of PS and AUC is described. Following a multidisciplinary, transparent, and widely acceptable process can result in the development of widely acceptable clinical guidance documents that can standardize best practices, improve quality, and result in effective and efficient patient care. The Society has been developing and/or revising new PS and AUC documents for high-value nuclear medicine procedures. Updated real-time information on these clinical guidelines can be found at www.snmmi.org/ps and www.snmmi.org/auc.

FDG PET/CT: EANM procedure guidelines for tumour imaging: version 2.0.

The purpose of these guidelines is to assist physicians in recommending, performing, interpreting and reporting the results of FDG PET/CT for oncological imaging of adult patients. PET is a quantitative imaging technique and therefore requires a common quality control (QC)/quality assurance (QA) procedure to maintain the accuracy and precision of quantitation. Repeatability and reproducibility are two essential requirements for any quantitative measurement and/or imaging biomarker. Repeatability relates to the uncertainty in obtaining the same result in the same patient when he or she is examined more than once on the same system. However, imaging biomarkers should also have adequate reproducibility, i.e. the ability to yield the same result in the same patient when that patient is examined on different systems and at different imaging sites. Adequate repeatability and reproducibility are essential for the clinical management of patients and the use of FDG PET/CT within multicentre trials. A common standardised imaging procedure will help promote the appropriate use of FDG PET/CT imaging and increase the value of publications and, therefore, their contribution to evidence-based medicine. Moreover, consistency in numerical values between platforms and institutes that acquire the data will potentially enhance the role of semiquantitative and quantitative image interpretation. Precision and accuracy are additionally important as FDG PET/CT is used to evaluate tumour response as well as for diagnosis, prognosis and staging. Therefore both the previous and these new guidelines specifically aim to achieve standardised uptake value harmonisation in multicentre settings.

Resident iPad use: has it really changed the game?

PURPOSE: The purpose of this study was to assess residents' usage patterns and opinions of the iPad as a tool for radiology education and clinical practice at an academic medical center. METHODS: All 38 radiology residents in our radiology program (postgraduate years 2 to 5) were provided with iPad 2 tablets and subscriptions to e-Anatomy and STATdx. After 6 months of device use, residents were surveyed to assess their opinions regarding the technology as a tool for education and clinical practice. RESULTS: A total of 36 residents (95%) completed the survey. Eighty-six percent reported daily iPad use. Radiology-specific applications, particularly e-Anatomy, were used weekly or daily by 88% of respondents. Most preferred to read journal articles on the iPad (70%), but the number of respondents preferring to read textbooks on the iPad (48.5%) compared with the traditional bound form (48.5%) was evenly divided. Residents were also divided on the clinical utility of the iPad. Most had not used the iPad to view radiologic examinations (75%). Fewer than half (47%) used their iPads during readout. Finally, only 12% had used the iPad to edit dictated reports. CONCLUSIONS: The iPad has generated excitement within the radiology community, particularly among resident educators, who are increasingly recognizing the unique needs of "millennial learners." This study showed that the majority of residents at the authors' institution have incorporated the iPad as an educational tool and use it as a learning aid. Incorporation of the iPad into clinical workflow has been less pronounced.

Sources of apical defects on a high-sensitivity cardiac camera: experiences from a practice performance assessment.

UNLABELLED: Apical perfusion artifacts seen on a high-sensitivity camera warranted a practice performance assessment to evaluate contributions from soft-tissue attenuation, patient positioning, and image processing techniques. METHODS: Cardiac perfusion studies (n = 534) spanning 5 mo were retrospectively reviewed. Images were acquired with the patient in the upright position, and attenuation correction was used. Regression analysis and contingency tables correlated clinical data to the presence of apical artifacts. RESULTS: There was a positive correlation of with female sex (χ(2) = 32, P < 0.001), degree of overlying soft tissues (χ(2) = 20, P < 0.002), and breast cleavage (χ(2) = 7, P < 0.008) and a negative correlation with angiography-confirmed disease (χ(2) = 6, P < 0.02). There was moderate interobserver agreement between 2 observers in determining the presence of apical defects (κ= 0.44, 95% confidence interval = 0.19-0.69), and there was a perceived improvement of apical defects using fewer iterative updates (χ(2) = 8, P < 0.003). CONCLUSION: An understanding of sources contributing to imaging artifacts is a crucial portion of quality assessment in radiology and nuclear medicine. A practice performance assessment study at our institution showed that apical artifacts on a new-generation cardiac camera can be partially attributed to overlying soft-tissue attenuation and ameliorated by altering the reconstruction.

Update on appropriate use criteria for amyloid PET imaging: dementia experts, mild cognitive impairment, and education. Amyloid Imaging Task Force of the Alzheimer's Association and Society for Nuclear Medicine and Molecular Imaging.

Amyloid PET imaging is a novel diagnostic test that can detect in living humans one of the two defining pathologic lesions of Alzheimer disease, amyloid-ß deposition in the brain. The Amyloid Imaging Task Force of the Alzheimer's Association and Society for Nuclear Medicine and Molecular Imaging previously published appropriate use criteria for amyloid PET as an important tool for increasing the certainty of a diagnosis of Alzheimer disease in specific patient populations. Here, the task force further clarifies and expands 3 topics discussed in the original paper: first, defining dementia experts and their use of proper documentation to demonstrate the medical necessity of an amyloid PET scan; second, identifying a specific subset of individuals with mild cognitive impairment for whom an amyloid PET scan is appropriate; and finally, developing educational programs to increase awareness of the amyloid PET appropriate use criteria and providing instructions on how this test should be used in the clinical decision-making process.