The active papillary muscle sign in 18F-FDG PET/CT cardiac sarcoidosis exams and its relationship with myocardial suppression.

OBJECTIVE: Papillary muscle (PM) activity may demonstrate true active cardiac sarcoidosis (CS) or mimic CS in 18FDG-PET/CT if adequate myocardial suppression (MS) is not achieved. We aim to examine whether PM uptake can be used as a marker of failed MS and measure the rate of PM activity presence in active CS with different dietary preparations. MATERIALS AND METHODS: We retrospectively reviewed PET/CTs obtained with three different dietary preparations. Diet-A: 24-h ketogenic diet with overnight fasting (n = 94); Diet-B: 18-h fasting (n = 44); and Diet-C: 72-h daytime ketogenic diet with 3-day overnight fasting (n = 98). Each case was evaluated regarding CS diagnosis (negative, positive, and indeterminant) and presence of PM activity. MaxSUV was measured from bloodpool, liver, and the most suppressed normal myocardium. Linear mixed-effects models were used to compare these factors between those with PM activity and those without. RESULTS: PM activity was markedly lower in the Diet-C group compared with others: Diet-C: 6 (6.1%), Diet-A: 36 (38.3%), and Diet-B: 26 (59.1%) (p < 0.001). MyocardiumMaxSUV was higher, and MyocardiummaxSUV/BloodpoolmaxSUV, MyocardiummaxSUV/LivermaxSUV ratios were significantly higher in the cases with PM activity (p < 0.001). Among cases that used Diet-C and had PM activity, 66.7% were positive and 16.7% were indeterminate. If Diet-A or Diet-B was used, those with PM activity had a higher proportion of indeterminate cases (Diet-A: 61.1%, Diet-B: 61.5%) than positive cases (Diet-A: 36.1%, Diet-B: 38.5%). CONCLUSION: Lack of PM activity can be a sign of appropriate MS. PM activity is less common with a specific dietary preparation (72-h daytime ketogenic diet with 3-day overnight fasting), and if it is present with this particular preparation, the likelihood that the case being true active CS might be higher than the other traditional dietary preparations.

Contrast enhancement in cerebral adrenoleukodystrophy: a comparison of T1 TSE and MPRAGE sequences.

PURPOSE: To compare conventional T1 TSE with MPRAGE for enhancement detection in cerebral adrenoleukodystrophy (CALD). MATERIALS AND METHODS: Contrast-enhanced T1 TSE and MPRAGE sequences of 34 CALD patients demonstrating enhancement were evaluated. Contrast ratios were calculated by drawing ROIs to the most enhancing part of demyelination and normal-appearing deep white matter on both T1 TSE and MPRAGE. A comparison was performed between ratios using paired T test. RESULTS: Mean age of 34 included male children was 8 (5-11 years). There was no statistically significant difference between T1 TSE and MPRAGE ratios. However, in 4 out of 34 examinations, minimal contrast enhancement was noted only in T1 TSE sequence. CONCLUSION: Our data indicate that both T1 TSE and MPRAGE sequences are valuable in determining contrast enhancement in CALD. Although there is not a statistically significant difference between the two techniques, T1 TSE sequence appears to be more sensitive for low degree of enhancement.

A bicentric retrospective analysis of clinical utility of 18F-fluciclovine PET in biochemically recurrent prostate cancer following primary radiation therapy: is it helpful in patients with a PSA rise less than the Phoenix criteria?

PURPOSE: 18F-Fluciclovine PET imaging has been increasingly used in the restaging of prostate cancer patients with biochemical recurrence (BCR); however, its clinical utility in patients with low prostate-specific antigen (PSA) levels following primary radiation therapy has not been well-studied. This study aims to determine the detection rate and diagnostic accuracy of 18F-fluciclovine PET and the patterns of prostate cancer recurrence in patients with rising PSA after initial radiation therapy, particularly in patients with PSA levels below the accepted Phoenix definition of BCR (PSA nadir +2 ng/mL). METHODS: This retrospective study included patients from two tertiary institutions who underwent 18F-fluciclovine PET scans for elevated PSA level following initial external beam radiation therapy, brachytherapy, and/or proton therapy. Logistic regression and receiver operating characteristic (ROC) curve analyses were performed to determine the diagnostic accuracy of 18F-fluciclovine PET and associations of PSA kinetic parameters with 18F-fluciclovine PET outcome. RESULTS: One hundred patients were included in this study. The overall detection rate on a patient-level was 79% (79/100). 18F-Fluciclovine PET was positive in 62% (23/37) of cases with PSA below the Phoenix criteria. The positive predictive value of 18F-fluciclovine PET was 89% (95% CI: 80-94%). In patients with PSA below the Phoenix criteria, the PSA velocity had the highest predictive value of 18F-fluciclovine PET outcome. PSA doubling time (PSADT) and PSA velocity were associated with the presence of extra-pelvic metastatic disease. CONCLUSION: 18F-Fluciclovine PET can identify recurrent disease at low PSA level and PSA rise below accepted Phoenix criteria in patients with suspected BCR after primary radiation therapy, particularly in patients with low PSADT or high PSA velocity. In patients with low PSADT or high PSA velocity, there is an increased probability of extra-pelvic metastases. Therefore, these patients are more likely to benefit from PET/CT or PET/MRI than pelvic MRI alone.

COMPARISON OF THE EFFECT OF THREE DIFFERENT DIETARY MODIFICATIONS ON MYOCARDIAL SUPPRESSION IN 18F-FDG PET/CT EVALUATION OF PATIENTS FOR SUSPECTED CARDIAC SARCOIDOSIS.

Rationale: A definitive dietary preparation recommendation is not possible based on literature in achievement of myocardial suppression for diagnosis of cardiac sarcoidosis (CS) with 18F-FDG PET/CT. Our goal is to compare three different dietary preparations in achievement of the best myocardial suppression and CS diagnosis. Methods: We retrospectively reviewed and compared three dietary preparations used at our institution. Three different diets were applied from 03/2014 to 12/2019. 24-h ketogenic diet with overnight fasting (n = 94); 18h-fasting (n = 44); 72-h daytime ketogenic diet with 3-day overnight fasting (n = 98). The interpretation of initial reports was recorded, and an independent radiologist (observer) retrospectively re-evaluated each case regarding CS diagnosis (Negative, Positive, Indeterminant) and myocardial suppression (Complete, Failed, Partial). Interobserver agreement was analyzed. We measured MaxSUV from bloodpool, liver, and the most suppressed normal myocardium. Results: We identified superior myocardial suppression with the 72-h preparation indicated by a higher bloodpool/myocardium and liver/myocardium ratios (P<0.001). Myocardial suppression rates for 72-h ketogenic diet, 24-h ketogenic diet and 18-h fasting preparations are as follows; Complete myocardial suppression: 96.9%/68.1%/52.3%, Failed myocardial suppression: 0%/23.4%/25%, Partial myocardial suppression: 3.1%/8.5%/22.7%) (P<0.001). The 72-hour preparation had significantly fewer "indeterminant" and "positive" exams. CS diagnosis rates for 72-h ketogenic diet, 24-h ketogenic diet and 18-h fasting preparations are as follows; Negative: 82.7%/52.1%/27.3%, Indeterminant: 2.0%/24.5%/40.9%, Positive: 15.3%/23.4%/31.8% (P<0.001). High agreement was present with the observer and the report (κ=0.88) Conclusion: A 72-h daytime ketogenic diet with 3-day overnight fasting, achieved substantially superior myocardial suppression versus 24-h ketogenic diet with overnight fasting and 18h-fasting using 18F-FDG PET/CT. This 72-h preparation results in significantly fewer "indeterminant" and potentially "false positive" CS results.

Role of Susceptibility-Weighted Imaging in Detecting Retinal Hemorrhages in Children with Head Trauma.

PURPOSE: This study was carried out to evaluate the utility of susceptibility-weighted imaging (SWI) in demonstrating retinal hemorrhages (RH) in pediatric head trauma. METHODS: Over a period of 7 years 67 children (age 0-4 years) with head trauma and MRI were included as either abusive head trauma (AHT) (n = 23), non-abusive head trauma (NAHT) (n = 38), or indeterminate (n = 6). Two pediatric neuroradiologists jointly reviewed the MR images for the presence of RH and sensitivity and specificity of SWI and T2WI were calculated. RESULTS: The dilated fundoscopic examination (DFE) was positive for RH in 18/23 (78.3%) of the AHT group, 5/38 (13.2%) in the NAHT group, and 4/6 (66.7%) in the indeterminate group. Regarding the SWI MRI findings, SWI was positive for RH in 13/23 (%56.5), while T2WI was positive in 6/23 (%26.1) of the AHT group. Based on utilizing DFE as a standard, the sensitivity and specificity of SWI in the detection of RH was 63% and 100%, respectively and 30% and 100%, respectively on T2WI. CONCLUSION: Our results suggest that SWI is a useful diagnostic tool for detection of RH in pediatric head trauma in whom DFE is difficult to perform.

Solitary Penile Metastasis of Prostate Cancer on 18F-Fluciclovine PET/CT Imaging in a Patient With PSA of 1 ng/mL.

An 85-year-old asymptomatic man with suspected biochemical recurrence of prostate cancer underwent an F-fluciclovine PET/CT scan, which revealed a solitary suspicious tracer uptake in the dorsal right corporal body of the proximal pendulous penis. The patient underwent ultrasound-guided fine-needle aspiration of the penile lesion, which revealed metastatic prostate cancer. The patient had definitive external beam radiation therapy 3 years before the examination. At the time of scan, the prostatic-specific antigen (PSA) was only 1.0 ng/mL, although the PSA doubling time was 2.6 months. It is unusual to detect a solitary penile metastasis in a patient with a low level of PSA.

"CHOICES": An acronym to aid in delineating potential causes of non-metabolic, non-infectious acute toxic leukoencephalopathy.

PURPOSE: To describe non-metabolic, non-infectious etiologies of acute toxic leukoencephalopathy (ATL) on DWI MRI, and provide a useful acronym to remember them. MATERIAL AND METHODS: Our PACS archive was reviewed, yielding 185 patients with suspected ATL per MRI reports and clinical follow up; infectious or metabolic causes were excluded. RESULT/DISCUSSION: The 87 included non-infectious, non-metabolic ATL patients' etiologies are represented by the acronym 'CHOICES': chemotherapy ('C',n = 34); heroin-induced ('H',n = 6), opioid analogues ('O',n = 14); immunosuppressant ('I',n = 11) or imidazole (n = 2); cocaine ('C',n = 1); environmental or ethanol abuse ('E',n = 5), splenial lesions ('S',n = 9), and 'other' (n = 5). CONCLUSION: The "CHOICES" acronym delineates various toxic etiologies of ATL.

Utility of Likert scale (Deauville criteria) in assessment of Chemoradiotherapy response of primary oropharyngeal squamous cell Cancer site.

INTRODUCTION: The aim of this study is to determine whether Likert scale (Deauville criteria) can be used to classify oropharyngeal squamous cell cancer (OPSCC) patients as 'responders' and 'nonresponders' by utilizing FDG-PET/CT for primary tumor site. The second aim is to compare the performance of methods used in interpretation of posttreatment PET/CT scans (Likert scale, SUVmax, ratios of SUVmax primary lesion to mediastinum 'SUVmax P/M' and SUVmax primary lesion to liver 'SUVmax P/L') in predicting treatment response. METHODS: Seventy-seven PET/CT scans were assessed by Deauville criteria, five-point Likert scale. SUVmax of primary lesion, SUVmax primary to mediastinum and SUVmax primary to liver ratios on first follow-up PET/CT were measured and calculated. Pathology results, clinical and imaging follow-up were used as standart reference. RESULTS: Sensitivity, specificity, positive predictive and negative predictive value of Likert scale were found to be 80%, 89.5%, 53.3% and 96.8% respectively. When Likert scale and PET parameters were compared, no statistically significant difference was found. Receiver operating characteristic (ROC) was used to determine the optimal cut-off points for SUVmax (found as 4) and for ratios (SUVmax P/M = 1.67and SUVmax P/L = 1.7) with the highest specificity and NPV. CONCLUSION: Likert scale adequately categorize patients as 'responders' and 'non-responders'. Since its NPV is high and interpretation is relatively easy, it can be utilized to evaluate OPSCC response to treatment in first follow up FDG PET/CT.

Various Cranial and Orbital Imaging Findings in Pediatric Abusive and Non-abusive Head trauma, and Relation to Outcomes.

BACKGROUND AND PURPOSE: Differentiating Abusive Head Trauma (AHT) from Non-abusive Head trauma (NAHT) has profound clinical prognostic and legal implications, as certain imaging findings can individually be more suggestive of NAHT, while others are more suggestive of AHT. This study was set out to evaluate for an association between the various imaging findings in AHT with outcome. MATERIAL AND METHODS: Over 7-years, 55 children (age 0-4 years') with head trauma and magnetic resonance imaging (MRI) were included as either: abusive (n = 16), non-abusive (n = 35), or indeterminate (n = 4). Two pediatric neuroradiologists jointly reviewed the imaging. The frequency of imaging findings and their association with ≥6 months' outcome were calculated. RESULTS: Comparing abusive versus non-abusive head trauma, complex subdural hematoma was present in 81% (n = 13/16) and 29% (n = 10/35), hypoxic-ischemic injury in 44% (n = 7/16) and 6% (n = 2/35), and diffuse axonal injury in 12% (n = 2/16) and 26% (n = 9/35), respectively. Susceptibility-weighted imaging (SWI) retinal hemorrhages were absent in non-abusive trauma (0/35), but present in 44% (n = 7/16) of the abusive group. In abuse, simple subdural hematomas were absent. Significant associations were found between the presence of abusive trauma with both hypoxic ischemic insult (OR = 12.83, p = 0.0024) and complex subdural hematoma (OR = 10.83, p = 0.0007). The presence of hypoxic ischemic injury (HII) did correlate significantly with clinical outcome (p = 0.017), while retinal hemorrhages on SWI and complex subdural hematoma did not (p = 0.1696-p = 0.2496). CONCLUSION: Neuroimaging findings can be helpful in discriminating these two conditions on presentation, as well as in helping solidify the suspicion of AHT. Regarding eventual outcome in AHT, the most important predictor is clearly HII.

Pretreatment quantitative 18F-FDG PET/CT parameters as a predictor of survival in adenoid cystic carcinoma of the salivary glands.

PURPOSE: The aim of this study was to determine the unique prognostic value of quantitative 18F-FDG PET/CT parameters to assess progression-free survival (PFS), distant metastasis-free survival (DMFS), and overall survival (OS) in patients with salivary gland adenoid cystic carcinoma (ACC). METHODS: We performed a retrospective study including 23 patients (15 men, 8 women; median age, 58 years; range, 21-91 years) with salivary gland ACC between January 2009 and October 2017 who underwent 18F-FDG PET/CT scan prior to treatment. Maximum, mean, peak, tumor-to-mediastinal blood pool and tumor-to-liver standardized uptake values (SUVmax, SUVmean, SUVpeak, SUVratio[med] and SUVratio[liver]), metabolic tumor volume (MTV), and total lesion glycolysis (TLG) were obtained from 18F-FDG PET/CT. The prognostic value of quantitative 18F-FDG PET/CT parameters and other clinicopathological variables were evaluated utilizing the Cox proportional regression analysis. RESULTS: The 3-year and 5-year OS for all the patients were 90.9%, and 62.3%, respectively. Log rank test determined that the SUVratio[med], SUVratio[liver], MTV and TLG were predictive factors of DMFS, PFS, and OS (p < 0.05), furthermore, SUVmax, minor salivary gland tumors and DM at initial diagnosis (M1 stage) were predictor for PFS; M1 stage and overall stage 3-4 predicted DMFS (all p < 0.05). Cox regression analyses confirmed that the higher SUVratio[med], SUVratio[liver], MTV, and TLG values predicted DMFS, PFS and OS independently, whereas SUVmax was an independent predictor of only PFS (p < 0.05). CONCLUSIONS: The pretreatment metabolic 18F-FDG PET/CT parameters may reflect tumor aggressiveness in patients with salivary gland ACC and may potentially be utilized as a prognostic biomarker.

The efficacy of fluoroscopy-guided epidural blood patch in the treatment of spontaneous and iatrogenic cerebrospinal fluid leakage.

OBJECTIVE: To evaluate patient outcomes following fluoroscopy-guided epidural blood patch (FGEBP), factors affecting the outcome, and to identify the rate of fluoroscopy-guided lumbar punctures (FGLP) requiring FGEBP. METHODS: All FGLPs and FGEBPs between January 2014 and May 2017 were retrospectively evaluated. Information regarding patient characteristics, details of previous dural puncture (DP), details of the FGEBP, and FGEBP outcome were recorded. The outcome was classified into three categories as "complete response", "partial response", and "no response". Patients with "complete response" were compared to the combined group of "no response" and "partial response", classified as "incomplete response". Two-sample/Fisher's exact (continued/categorical variables) tests were used (p < 0.05). RESULTS: Sity-seven FGEBPs were performed in 63 patients (female/male, 36/27; mean age/BMI 38/28.2). Fifty-nine were referred following DP; 31 were performed by radiologists. The rate of FGLPs requiring FGEBP was 1.78% within 3.5 years. The mean DP-FGEBP interval was 4.8 days. "Complete response" was achieved in 56 (84.8%), "no response" was found following 4 (6%) procedures. Average applied blood volume was 16 cc (5-30 cc). No difference was found between "complete response" and "incomplete response" groups regarding age, sex, BMI, DP performer, DP level, DP fluoroscopy time, DP needle caliber/type, FGEBP level, FGEBP needle caliber/type, FGEBP fluoroscopy time, FGEBP performer, and applied blood volume (p > 0.05). Despite approaching significance, no statistically significant difference was found regarding the presence of previous DP (p = 0.06). CONCLUSIONS: The efficacy of FGEBP is high in a group of patients referred to radiology for treatment of CSF leakage with complete response in 84.8% of patients. KEY POINTS: • Fluoroscopy-guided epidural blood patch completely resolved symptoms in 85% of post-dural puncture headaches. • The success approaches 95% when including the patients with partial resolution of symptoms. • Epidural blood patch rate is found 1.8% following 1703 fluoroscopy-guided lumbar punctures.

Review of diffuse cortical injury on diffusion-weighted imaging in acutely encephalopathic patients with an acronym: "CRUMPLED".

PURPOSE: Acute encephalopathic syndromes can present a diagnostic challenge due to the wide range of possible etiologies, which also can have vastly different outcomes. The presence of diffuse cortical injury (DCI) on diffusion-weighted imaging (DWI) can help narrow the differential diagnosis. The aim of this review is to categorize the range of possible etiologies of DCI into a useful acronym, "CRUMPLED". METHODS: A review of the PACS system was completed to find a characteristic example of patients with DCI on DWI from different etiologies. The diagnosis was confirmed for each example via a subsequent review of the electronic medical record used to assess for data such as biopsy results, laboratory values, and clinical correlation. The electronic exhibit intends to demonstrate several sample cases of each letter within the acronym, and to demonstrate which types of DCI are potentially reversible or irreversible. FINDINGS/DISCUSSION: The possible etiologies of DCI on DWI can be organized using the acronym "CRUMPLED": 'C' = Creutzfeldt-jakob disease, 'R' =  reversible cerebral vasoconstriction syndrome; 'U' = urea cycle disorders (hyperammonemia) and Uremia; 'M' = mitochondrial (cytopathy/encephalopathy); 'P' = prolonged seizure and posterior reversible encephalopathy (PRES); 'L' = laminar necrosis (hypoxic-ischemic encephalopathy) and liver disease (acute hepatic encephalopathy); 'E' = encephalitis (infectious meningoencephalitis); 'D' = diabetes mellitus (hypoglycemia). Other secondary imaging findings (outside of DWI) can be used to help differentiate between the aforementioned etiologies, such as the use of ADC maps, FLAIR imaging, intravenous contrast. CONCLUSION: "CRUMPLED" is proposed as a convenient acronym for the categorization of a diverse range of acute etiologies associated with DCI on DWI, arising from varying degrees of cytotoxic edema. These etiologies can range from being potentially reversible (e.g. hyperammonemia or prolonged seizures) to irreversible (e.g. hypoxic-ischemic injury).

Differentiating Transudative From Exudative Ascites Using Quantitative B-Mode Gray-Scale Ultrasound Histogram.

OBJECTIVE: The purpose of this article is to differentiate exudative from transudative ascites using B-mode gray-scale ultrasound histogram analysis. SUBJECTS AND METHODS: Sixty-two consecutive patients with ascites were prospectively studied from June 2014 through June 2015. All underwent ultrasound (US) and paracentesis in the radiology department. Five patients were excluded (three with hemorrhage and two with peritoneal carcinomatosis). The remaining 57 patients were divided into those with exudative and transudative ascites according to results of paracentesis. Electronically recorded US images were transferred to a workstation, and gray-scale histograms were generated. The ascites-to-rectus abdominis muscle echogenicity ratio (ARAER) was obtained from ascites adjacent to the rectus abdominis muscle. ROC curves were used to evaluate the sensitivity and specificity of this method in differentiating exudative from transudative ascites. RESULTS: ARAERs for exudative ascites were significantly higher than those for transudative ascites (p < 0.001). ROC was done to evaluate ARAERs for exudative ascites. The best cutoff value for ARAER histogram was 0.002. The sensitivity and specificity of ARAER were 87.5% and 79.2% (AUC = 0.843), respectively. CONCLUSION: ARAER is an easily applicable noninvasive quantitative sonographic method with high sensitivity and specificity in differentiating exudative from transudative ascites.