HIV infection is associated with compromised tumor microenvironment adaptive immune reactivity in Hodgkin Lymphoma.

The impact of Human Immunodeficiency Virus (HIV) infection on the tumor microenvironment (TME) of classic Hodgkin lymphoma (cHL), one of the most common co-morbidities following HIV infection, is not well understood. Here, we have employed multiplexed immunofluorescence (mIF) and spatial transcriptomic analysis to dissect the impact of viral infections (EBV, HIV/EBV) on cHL TME. Compared to HIV-EBV-, HIV-EBV+ cHL TME was characterized by higher cell densities of CD8high T cells co-expressing inhibitory receptors (PD-1, TIGIT), macrophage subsets and an in situ inflammatory molecular profile associated with increased expression of TCR and BCR cell signaling pathways. Compared to HIV-EBV+, HIV+EBV+ cHL TME was characterized by significantly less CD8high T cells co-expressing PD-1 and TIGIT, a profile concomitant with significantly increased cell densities of CD155high neoplastic cells. Significant downregulation of in situ TCR-signaling and upregulation of extracellular matrix reorganization pathways were found in HIV+EBV+ cHL TME, in line with an altered topological organization of CXCL13 and heparan sulfate, an extracellular matrix glycosaminoglycan. Our data reveal the complexity of the cellular and molecular composition of cHL TME in the presence of viral infections, with possible implications for combinatorial immunotherapies. Furthermore, the data suggest specific molecular targets and pathways for further investigation that could improve our understanding of possible mechanistic links between HIV and lymphomagenesis.

Targeting ATP12A, a Nongastric Proton Pump α Subunit, for Idiopathic Pulmonary Fibrosis Treatment.

Idiopathic pulmonary fibrosis (IPF) is a pathological condition of unknown etiology that results from injury to the lung and an ensuing fibrotic response that leads to the thickening of the alveolar walls and obliteration of the alveolar space. The pathogenesis is not clear, and there are currently no effective therapies for IPF. Small airway disease and mucus accumulation are prominent features in IPF lungs, similar to cystic fibrosis lung disease. The ATP12A gene encodes the α-subunit of the nongastric H+, K+-ATPase, which functions to acidify the airway surface fluid and impairs mucociliary transport function in patients with cystic fibrosis. It is hypothesized that the ATP12A protein may play a role in the pathogenesis of IPF. The authors' studies demonstrate that ATP12A protein is overexpressed in distal small airways from the lungs of patients with IPF compared with normal human lungs. In addition, overexpression of the ATP12A protein in mouse lungs worsened bleomycin induced experimental pulmonary fibrosis. This was prevented by a potassium competitive proton pump blocker, vonoprazan. These data support the concept that the ATP12A protein plays an important role in the pathogenesis of lung fibrosis. Inhibition of the ATP12A protein has potential as a novel therapeutic strategy in IPF treatment.

Bowel habits, faecal microbiota and faecal bile acid composition of healthy adults consuming fruit pomace fibres: two-arm, randomised, double-blinded, placebo-controlled trials.

Dietary fibre modulates gastrointestinal (GI) health and function, providing laxation, shifting microbiota, and altering bile acid (BA) metabolism. Fruit juice production removes the polyphenol- and fibre-rich pomace fraction. The effects of orange and apple pomaces on GI outcomes were investigated in healthy, free-living adults. Healthy adults were enrolled in two double-blinded, crossover trials, being randomised by baseline bowel movement (BM) frequency. In the first trial, subjects (n 91) received orange juice (OJ, 0 g fibre/d) or OJ + orange pomace (OJ + P, 10 g fibre/d) for 4 weeks, separated by a 3-week washout. Similarly, in the second trial, subjects (n 90) received apple juice (AJ, 0 g fibre/d) or AJ + apple pomace (AJ + P, 10 g fibre/d). Bowel habit diaries, GI tolerance surveys and 3-d diet records were collected throughout. Fresh faecal samples were collected from a participant subset for microbiota and BA analyses in each study. Neither pomace interventions influenced BM frequency. At Week 4, OJ + P tended to increase (P = 0·066) GI symptom occurrence compared with OJ, while AJ + P tended (P = 0·089) to increase flatulence compared with AJ. Faecalibacterium (P = 0·038) and Negativibacillus (P = 0·043) were differentially abundant between pre- and post-interventions in the apple trial but were no longer significant after false discovery rate (FDR) correction. Baseline fibre intake was independently associated with several microbial genera in both trials. Orange or apple pomace supplementation was insufficient to elicit changes in bowel habits, microbiota diversity or BA of free-living adults with healthy baseline BM. Future studies should consider baseline BM frequency and habitual fibre intake.

The Effect of Multi-Vitamin/Multi-Mineral Supplementation on Nutritional Status in Older Adults Receiving Drug Therapies: A Double-Blind, Placebo-Controlled Trial.

Polypharmacy regimens may increase the susceptibility of older adults to micronutrient inadequacy and deficiency via impairment of nutritional status. We hypothesized that a multi-vitamin-mineral supplement (MVMS) could improve nutritional status in older adults prescribed diuretics, metformin, and/or proton pump inhibitors (PPIs). We conducted a randomized, double-blind, placebo controlled, parallel clinical trial in which eligible subjects were instructed to consume either a MVMS or placebo for 16 wk. Fasting blood was collected at baseline, 8, and 16 wk and the status of selected vitamins and minerals determined. Thirty-five and 19 men and women aged 45-75 yrs in the in MVMS and placebo arms, respectively, completed the trial. The mean total number of medications among the three drug classes taken by participants did not differ between two groups. The status of vitamins B1, B12, C and folate and calcium, copper, magnesium and zinc at baseline were within normal ranges. The MVMS group had a greater change in nutrient status after 16 wk compared to the placebo group for serum folate (7.5 vs. -1.6 ng/mL, p < 0.0001), vitamin B12 (159.2 vs. -33.9 pg/mL, p = 0.007), and plasma vitamin C (0.2 vs. 0.0 mg/dL, p = 0.004). Other measured vitamins and minerals were not significantly changed during the intervention. In conclusion, the status of vitamins B12, C and folate improved with MVMS but remained within normal ranges in older adults taking diuretics, metformin, and/or PPIs.

Infective thrombophlebitis after great saphenous vein cyanoacrylate embolization.

The use of cyanoacrylate embolization has increased in interest as a safe, effective, and minimally invasive method to treat symptomatic saphenous reflux. The procedure is generally well tolerated by patients, and complications such as phlebitis are minor and usually self-limiting. Postprocedural infections have been described but occur infrequently and usually in the early postoperative course. In the present case report, we have described a late-onset infective thrombophlebitis of the great saphenous vein after cyanoacrylate embolization, requiring surgical excision of the treated vein.

Resolution of Diplopia and Torsion Following Yttrium Aluminum Garnet (YAG) Laser Capsulotomy in a Patient With the Ocular Tilt Reaction.

The ocular tilt reaction is a rare neuro-ophthalmological phenomenon commonly occurring due to an injury to the vestibulo-ocular pathway, or a thalamic, brainstem, or cerebellar lesion. Most ocular tilt reactions are transient and demonstrate spontaneous recovery. This report documents the immediate resolution of diplopia and the patient's ocular tilt reaction following visual recovery from left yttrium aluminum garnet laser capsulotomy.

Transduction of Pig Small Airway Epithelial Cells and Distal Lung Progenitor Cells by AAV4.

Cystic fibrosis (CF) is caused by genetic mutations of the CF transmembrane conductance regulator (CFTR), leading to disrupted transport of Cl- and bicarbonate and CF lung disease featuring bacterial colonization and chronic infection in conducting airways. CF pigs engineered by mutating CFTR develop lung disease that mimics human CF, and are well-suited for investigating CF lung disease therapeutics. Clinical data suggest small airways play a key role in the early pathogenesis of CF lung disease, but few preclinical studies have focused on small airways. Efficient targeted delivery of CFTR cDNA to small airway epithelium may correct the CFTR defect and prevent lung infections. Adeno-associated virus 4 (AAV4) is a natural AAV serotype and a safe vector with lower immunogenicity than other gene therapy vectors such as adenovirus. Our analysis of AAV natural serotypes using cultured primary pig airway epithelia showed that AAV4 has high tropism for airway epithelia and higher transduction efficiency for small airways compared with large airways. AAV4 mediated the delivery of CFTR, and corrected Cl- transport in cultured primary small airway epithelia from CF pigs. Moreover, AAV4 was superior to all other natural AAV serotypes in transducing ITGα6ß4+ pig distal lung progenitor cells. In addition, AAV4 encoding eGFP can infect pig distal lung epithelia in vivo. This study demonstrates AAV4 tropism in small airway progenitor cells, which it efficiently transduces. AAV4 offers a novel tool for mechanistical study of the role of small airway in CF lung pathogenesis in a preclinical large animal model.

The Role of Oat Nutrients in the Immune System: A Narrative Review.

Optimal nutrition is the foundation for the development and maintenance of a healthy immune system. An optimal supply of nutrients is required for biosynthesis of immune factors and immune cell proliferation. Nutrient deficiency/inadequacy and hidden hunger, which manifests as depleted nutrients reserves, increase the risk of infectious diseases and aggravate disease severity. Therefore, an adequate and balanced diet containing an abundant diversity of foods, nutrients, and non-nutrient chemicals is paramount for an optimal immune defense against infectious diseases, including cold/flu and non-communicable diseases. Some nutrients and foods play a larger role than others in the support of the immune system. Oats are a nutritious whole grain and contain several immunomodulating nutrients. In this narrative review, we discuss the contribution of oat nutrients, including dietary fiber (ß-glucans), copper, iron, selenium, and zinc, polyphenolics (ferulic acid and avenanthramides), and proteins (glutamine) in optimizing the innate and adaptive immune system's response to infections directly by modulating the innate and adaptive immunity and indirectly by eliciting changes in the gut microbiota and related metabolites.

Long-term Results of 180 Consecutive Patients with Abdominal Aortic Aneurysm Treated with the Endurant Stent Graft System.

BACKGROUND: Registry studies have shown that the Endurant stent graft is associated with low rates of all-cause and aneurysm-related mortality when used for the endovascular treatment of abdominal aortic aneurysm (AAA). However, many were limited by length of follow-up and all had a proportion of patients lost to follow-up. The aim of this study is to report results from a large, real-world experience using Endurant, utilizing methods to ensure complete ascertainment of mortality. METHODS: This study describes a large, single vascular unit experience using the Endurant stent graft in consecutive patients treated between August 2008 and March 2019. RESULTS: One-hundred eighty patients (mean age 76.0 ± 8.6 years; 90% male) with mean AAA diameter of 57.5 ± 10.5 mm underwent endovascular aneurysm repair (EVAR). Technical success was achieved in all cases. At median follow-up of 55.0 months (interquartile range 29.8-79.0), 51 (28.3%) patients had died. Kaplan-Meier estimate of 5-year overall survival and freedom from aneurysm-related death was 71.6% and 99.4%, respectively. Lower survival rates were observed in patients who underwent EVAR at age ≥80 years (59.2% vs. 78.3%, P < 0.01) and with aneurysm diameter ≥70 mm (55.6% vs. 73.8%, P = 0.03). Thirteen endoleaks (7.2%; 4 type 1A, 2 type 1B, 7 type 2) were observed during follow-up (mean time from implantation 8.7 ± 4.2, range 1-52 months). Eleven patients (6.1%) required secondary intervention for limb occlusion (n = 7), endoleak (n = 3), and restenosis (n = 1). Patients treated within (n = 104; 57.8%) and outside (n = 76; 42.2%) the manufacturer's instructions for use (IFU) had similar rates of endoleak (7 [6.7%] vs. 6 [7.9%]; P = 0.76), secondary re-intervention (7 [6.7%] vs. 4 [5.3%]; P = 0.74) and overall-survival (72 [69.2%] vs. 55 [72.3%]; P = 0.46). CONCLUSIONS: Results from this real-world study of consecutive patients treated for AAA using the Endurant stent graft demonstrate that it is safe and effective, with excellent long-term outcomes for anatomy that falls both inside and outside IFU recommendations.

Highly Bioavailable Forms of Curcumin and Promising Avenues for Curcumin-Based Research and Application: A Review.

Curcumin exerts a wide range of beneficial physiological and pharmacological activities, including antioxidant, anti-amyloid, anti-inflammatory, anti-microbial, anti-neoplastic, immune-modulating, metabolism regulating, anti-depressant, neuroprotective and tissue protective effects. However, its poor solubility and poor absorption in the free form in the gastrointestinal tract and its rapid biotransformation to inactive metabolites greatly limit its utility as a health-promoting agent and dietary supplement. Recent advances in micro- and nano-formulations of curcumin with greatly enhanced absorption resulting in desirable blood levels of the active forms of curcumin now make it possible to address a wide range of potential applications, including pain management, and as tissue protective. Using these forms of highly bioavailable curcumin now enable a broad spectrum of appropriate studies to be conducted. This review discusses the formulations designed to enhance bioavailability, metabolism of curcumin, relationships between solubility and particle size relative to bioavailability, human pharmacokinetic studies involving formulated curcumin products, the widely used but inappropriate practice of hydrolyzing plasma samples for quantification of blood curcumin, current applications of curcumin and its metabolites and promising directions for health maintenance and applications.

Avocado Consumption Increases Macular Pigment Density in Older Adults: A Randomized, Controlled Trial.

Lutein is selectively incorporated into the macula and brain. Lutein levels in the macula (macular pigment; MP) and the brain are related to better cognition. MP density (MPD) is a biomarker of brain lutein. Avocados are a bioavailable source of lutein. This study tests the effects of the intake of avocado on cognition. This was a six-month, randomized, controlled trial. Healthy subjects consumed one avocado (n = 20, 0.5 mg/day lutein, AV) vs. one potato or one cup of chickpeas (n = 20, 0 mg/day lutein, C). Serum lutein, MPD, and cognition were assessed at zero, three, and six months. Primary analyses were conducted according to intent-to-treat principles, with repeated-measures analysis. At six months, AV increased serum lutein levels by 25% from baseline (p = 0.001). C increased by 15% (p = 0.030). At six months, there was an increase in MPD from baseline in AV (p = 0.001) and no increase in C. For both groups, there was an improvement in memory and spatial working memory (p = 0.001; p = 0.032, respectively). For AV only there was improved sustained attention (p = 0.033), and the MPD increase was related to improved working memory and efficiency in approaching a problem (p = 0.036). Dietary recommendations including avocados may be an effective strategy for cognitive health.

Collagen peptides ameliorate intestinal epithelial barrier dysfunction in immunostimulatory Caco-2 cell monolayers via enhancing tight junctions.

Dysfunction of the intestinal barrier plays a key role in the pathogenesis of inflammatory bowel disease (IBD) and multiple organ failure. The effect of Alaska pollock skin-derived collagen and its 3 tryptic hydrolytic fractions, HCP (6 kDa retentate), MCP (3 kDa retentate) and LCP (3 kDa permeate) on TNF-α induced barrier dysfunction was investigated in Caco-2 cell monolayers. TNF-α induced barrier dysfunction was significantly attenuated by the collagen and its peptide fractions, especially LCP, compared to TNF-α treated controls (P < 0.05). Compared to a negative control, 24 h pre-incubation with 2 mg mL-1 LCP significantly alleviated the TNF-α induced breakdown of the tight junction protein ZO-1 and occludin and inhibited MLC phosphorylation and MLCK expression. The activation of NFκB and Elk-1 was suppressed by LCP. Thus, collagen peptides may attenuate TNF-α induced barrier dysfunction of Caco-2 cells by inhibiting the NFκB and ERK1/2-mediated MLCK pathway with associated decreases in ZO-1 and occludin protein expression.

CT Colonographic Screening of Patients With a Family History of Colorectal Cancer: Comparison With Adults at Average Risk and Implications for Guidelines.

OBJECTIVE: The purposes of this study were to compare rates of lesion detection at CT colonographic (CTC) screening of adults without symptoms who had and who did not have a family history of colorectal cancer according to American Cancer Society guidelines and to consider the clinical implications. MATERIALS AND METHODS: Over 134 months, consecutively registered CTC cohorts of adults without symptoms who had (n = 156; 88 [56.4%] women; 68 [43.6%] men; mean age, 56.3 years) and who did not have (n = 8857; 4757 [53.7%] women; 4100 [46.3%] men; mean age, 56.6 years) an American Cancer Society-defined family history of colorectal cancer (first-degree relative with diagnosis before age 60 years or two first-degree relatives with diagnosis at any age) were compared for relevant colorectal findings. RESULTS: For the family history versus no family history cohorts, the frequency of all nondiminutive polyps (≥ 6 mm) reported at CTC was 23.7% versus 15.5% (p = 0.007); small polyps (6-9 mm), 13.5% versus 9.1% (p = 0.068); and large polyps (≥ 10 mm), 10.2% versus 6.5% (p = 0.068). The rate of referral for colonoscopy was greater for the family history cohort (16.0% vs 10.5%; p = 0.035). However, the frequencies of proven advanced adenoma (4.5% vs 3.2%; p = 0.357), nonadvanced adenoma (5.1% vs 2.6%; p = 0.070), and cancer (0.0% vs 0.4%; p = 0.999) were not significantly increased. The difference in positive rates between the two cohorts (11.5% vs 4.3%; p < 0.001) was primarily due to nonneoplastic findings of no colorectal cancer relevance, such as small hyperplastic polyps, diverticular disease, and false-positive CTC findings. CONCLUSION: Although the overall CTC-positive and colonoscopy referral rates were higher in the family history cohort, the clinically relevant frequencies of advanced neoplasia and cancer were not sufficiently increased to preclude CTC screening. These findings support the use of CTC as a front-line screening option in adults with a family history of colorectal cancer.

Prospective Evaluation of Reduced Dose Computed Tomography for the Detection of Low-Contrast Liver Lesions: Direct Comparison with Concurrent Standard Dose Imaging.

OBJECTIVES: To prospectively compare the diagnostic performance of reduced-dose (RD) contrast-enhanced CT (CECT) with standard-dose (SD) CECT for detection of low-contrast liver lesions. METHODS: Seventy adults with non-liver primary malignancies underwent abdominal SD-CECT immediately followed by RD-CECT, aggressively targeted at 60-70 % dose reduction. SD series were reconstructed using FBP. RD series were reconstructed with FBP, ASIR, and MBIR (Veo). Three readers-blinded to clinical history and comparison studies-reviewed all series, identifying liver lesions ≥4 mm. Non-blinded review by two experienced abdominal radiologists-assessing SD against available clinical and radiologic information-established the reference standard. RESULTS: RD-CECT mean effective dose was 2.01 ± 1.36 mSv (median, 1.71), a 64.1 ± 8.8 % reduction. Pooled per-patient performance data were (sensitivity/specificity/PPV/NPV/accuracy) 0.91/0.78/0.60/0.96/0.81 for SD-FBP compared with RD-FBP 0.79/0.75/0.54/0.91/0.76; RD-ASIR 0.84/0.75/0.56/0.93/0.78; and RD-MBIR 0.84/0.68/0.49/0.92/0.72. ROC AUC values were 0.896/0.834/0.858/0.854 for SD-FBP/RD-FBP/RD-ASIR/RD-MBIR, respectively. RD-FBP (P = 0.002) and RD-MBIR (P = 0.032) AUCs were significantly lower than those of SD-FBP; RD-ASIR was not (P = 0.052). Reader confidence was lower for all RD series (P < 0.001) compared with SD-FBP, especially when calling patients entirely negative. CONCLUSIONS: Aggressive CT dose reduction resulted in inferior diagnostic performance and reader confidence for detection of low-contrast liver lesions compared to SD. Relative to RD-ASIR, RD-FBP showed decreased sensitivity and RD-MBIR showed decreased specificity. KEY POINTS: • Reduced-dose CECT demonstrates inferior diagnostic performance for detecting low-contrast liver lesions. • Reader confidence is lower with reduced-dose CECT compared to standard-dose CECT. • Overly aggressive dose reduction may result in misdiagnosis, regardless of reconstruction algorithm. • Careful consideration of perceived risks versus benefits of dose reduction is crucial.

A pictorial review of reconstructive foot and ankle surgery: hallux abductovalgus.

This pictorial review focuses on basic procedures performed within the field of podiatric surgery, specifically for the hallux abductovalgus or "bunion" deformity. Our goal is to define objective radiographic parameters that surgeons utilize to initially define deformity, lead to procedure selection and judge post-operative outcomes. We hope that radiologists will employ this information to improve their assessment of post-operative radiographs following reconstructive foot surgeries. First, relevant radiographic measurements are defined and their role in procedure selection explained. Second, the specific surgical procedures of the distal metatarsal, metatarsal shaft, metatarsal base, and phalangeal osteotomies are described in detail. Additional explanations of arthrodesis of the first metatarsal-phalangeal and metatarsal-cuneiform joints are also provided. Finally, specific plain film radiographic findings that judge post-operative outcomes for each procedure are detailed.

Percutaneous Microwave Ablation of an Insulinoma in a Patient with Refractory Symptomatic Hypoglycemia.

Insulinomas are the most common functioning pancreatic neuroendocrine tumors (pNETs). Surgical excision is the preferred therapy, and medical treatment with diazoxide or octreotide is typically reserved for those who are poor surgical candidates. A recent emergence of minimally invasive treatment modalities has led to reports of successful radiofrequency and ethanol ablation of insulinomas. We report the first use of microwave ablation for treatment of an insulinoma in a patient with medical comorbidities contraindicating surgery.

Wide-field imaging and flow cytometric analysis of cancer cells in blood by fluorescent nanodiamond labeling and time gating.

Nanodiamonds containing high density ensembles of negatively charged nitrogen-vacancy (NV(-)) centers are promising fluorescent biomarkers due to their excellent photostability and biocompatibility. The NV(-) centers in the particles have a fluorescence lifetime of up to 20 ns, which distinctly differs from those (<10 ns) of cell and tissue autofluorescence, making it possible to achieve background-free detection in vivo by time gating. Here, we demonstrate the feasibility of using fluorescent nanodiamonds (FNDs) as optical labels for wide-field time-gated fluorescence imaging and flow cytometric analysis of cancer cells with a nanosecond intensified charge-coupled device (ICCD) as the detector. The combined technique has allowed us to acquire fluorescence images of FND-labeled HeLa cells in whole blood covered with a chicken breast of ~0.1-mm thickness at the single cell level, and to detect individual FND-labeled HeLa cells in blood flowing through a microfluidic device at a frame rate of 23 Hz, as well as to locate and trace FND-labeled lung cancer cells in the blood vessels of a mouse ear. It opens a new window for real-time imaging and tracking of transplanted cells (such as stem cells) in vivo.

Hemosuccus Pancreaticus: A Mysterious Cause of Gastrointestinal Bleeding.

Hemosuccus pancreaticus (bleeding from the pancreatic duct into the gastrointestinal tract via the ampulla of Vater) is a rare, potentially life-threatening and obscure cause of upper gastrointestinal bleeding. It is caused by rupture of the psuedoaneurysm of a peripancreatic vessel into pancreatic duct or pancreatic psuedocyst in the context of pancreatitis or pancreatic tumors. It can pose a significant diagnostic and therapeutic dilemma due to its anatomical location and that bleeding into the duodenum is intermittent and cannot be easily diagnosed by endoscopy. A 61-year-old female with HIV and alcoholism presented with 3 weeks of intermittent abdominal pain and melena. Examination revealed hypotension with pallor and mild epigastric tenderness. She was found to have severe anemia and a high serum lipase. It was decided to perform a contrast-enhanced computed tomography (CT) scan that demonstrated a hemorrhagic pancreatic pseudocyst with possible active bleeding into the cyst. An emergent angiogram showed a large pseudoaneurysm of the pancreaticoduodenal artery that was successfully embolized. Subsequent endoscopy showed blood near ampulla of Vater confirming the diagnosis of hemosuccus pancreaticus. Thus the bleeding pseudocyst was communicating with pancreatic duct. The patient had no further episodes of gastrointestinal bleeding. Hemosuccus pancreaticus should be considered in patients with intermittent crescendo-decrescendo abdominal pain, gastrointestinal bleeding and a high serum lipase. Contrast-enhanced CT scan can be an excellent initial diagnostic modality and can lead to prompt angiography for embolization of the bleeding pseudoaneurysm and can eliminate the need for surgery.

The validity and reliability of preoperative radiographic canal diameter measurements of the femur.

BACKGROUND: The femoral canal is frequently measured preoperatively in cases where an intramedullary device is planned for operative fixation of a fracture. To our knowledge, a formal assessment of validity and reliability of preoperative canal measurements has not been previously performed. QUESTIONS/PURPOSES: This study aims to determine the validity and reliability of preoperative canal measurements of the femur made on plain radiographs using comparison with curved planar reformation software as the gold standard. METHODS: Fifty-six patients were identified based on availability of anterior-posterior (AP) and lateral radiographs of the femur and computed tomography (CT) of the lower extremity. Four "raters" measured the canal diameter at its narrowest point and the distance from the lesser trochanter to the isthmus on the AP, lateral radiograph, and CT. The width of the femoral nail on AP radiographs was also measured to determine magnification error. Curved planar reformation (CPR) was used to provide the most accurate calculation of the canal diameter. RESULTS: Compared to the isthmus position determined by CPR, the measurement was most accurate on an AP and the diameter of the canal was most accurate using coronal CT, followed by AP radiographs. The measured canal diameter of the fractured femur on APs was compared to that of the used implant and varied by 1 mm. DISCUSSION/CONCLUSION: The AP plain radiographic measurement was found to be more accurate for determination of the canal diameter compared to the lateral radiograph. These findings confirm the utility of preoperative canal measurements in predicting the feasibility of placing a specific size intramedullary implant.