Accuracy of hepatobiliary scintigraphy and added value of SPECT/CT versus planar imaging for diagnosing biliary atresia.

OBJECTIVE: Hepatobiliary scintigraphy (HBS) is an important tool in diagnosing biliary atresia in infants. There is limited evidence on the use of single photon emission computed tomography/computed tomography (SPECT/CT) as an additional imaging method to planar imaging. We evaluated the value of SPECT/CT in unclear cases of planar HBS. SUBJECTS AND METHODS: Consecutive patients with suspected biliary atresia who underwent guideline-compliant HBS from January 2010 until March 2020 were reviewed, and cases with SPECT/CT were identified. Each step within the imaging procedure (dynamic, static [early and late], and SPECT/CT) was blindly reread in consensus by two observers and categorized based on a 5-point scale: 0, definitely no bowel excretion (i.e., atresia confirmed); 1, probably positive; 2,equivocal; 3, probably negative; and 4, definite negative (i.e., atresia not confirmed). In this analysis, categories were dichotomized as negative for biliary atresia (scores 3-4) or positive (scores 0-2, including equivocal scans). Available follow-up information constituted the standard of truth (SoT). RESULTS: Twenty-three infants had HBS, among which ten (4 boys and 6 girls; mean age 36 days; range 8-108) underwent SPECT/CT. Single photon emission computed tomography SPECT/CT was performed as early examination (<8h) in 3 subjects and late (8 to 24 h) in 7 infants. Reread SPECT/CT was categorized as positive for atresia in three infants and negative in seven infants. The SoT showed biliary atresia in one of ten patients. Single photon emission computed tomography/CT was true positive in one case, false positive in two, and true negative in seven. No false negative cases were noted. The diagnostic performance of SPECT/CT showed a sensitivity of 100%, specificity of 78%, positive predictive value (PPV) of 33%, negative predictive value (NPV) of 100%, and accuracy of 90%. For comparison, the diagnostic performance of planar HBS showed a sensitivity of 100%, specificity of 67%, PPV of 25%, NPV of 100%, and accuracy of 70%. In summary, the addition of SPECT/CT to planar HBS improved specificity andaccuracyand marginally improved PPV. Single photon emission computed tomography/CT provided more confidence in the final conclusion in 8/10 patients. In the remaining two cases, SPECT/CT did not improve the level of confidence (one remained equivocal, and one changed from probably no excretion to equivocal). CONCLUSION: These preliminary data demonstrated increased accuracy of add-on SPECT to planar HBS predominantly due to improved specificity. This finding is consistent with the existing but limited literature and supports the recommendation of routine use of SPECT/CT or SPECT.

Incidental detection of colorectal lesions on 18 F-FDG-PET/CT is associated with high proportion of malignancy: A study in 549 patients.

Background and study aims Further diagnostics of incidental colorectal lesions on 18 F-fluorodeoxyglucose (FDG) positron emission tomography/computed tomography (PET/CT) is questionable. Therefore, we aimed to evaluate the clinical importance of incidentally detected colorectal lesions on FDG-PET/CT. Patients and methods In the North Denmark Region, a retrospective study was performed among 19,987 patients who had an FDG-PET/CT from January 2006 to December 2015. Among these patients, we identified patients with a colonoscopy within 12 months from the PET/CT scan and a description of incidental colorectal PET-avid lesions on the PET/CT. PET findings were compared with colonoscopy-detected lesions and eventually histopathology. Results Incidental PET-avid lesions were observed in 549 patients. Colonoscopy revealed lesions in 457 (83 %), among whom 338 patients had a final histopathological diagnosis. Malignant and premalignant lesions were found in 297 patients (54 % among patients with a PET-avid lesion). The lesions were cancer in 76 patients and adenoma in 221 patients of whom 30 had high-grade and 191 low-grade adenomas. The findings changed patient management in 166 cases (30 % of all patients with a PET-avid lesion). A colonoscopy-based surveillance program was initiated for 80 % of patients with high-grade adenoma. No patients with PET-avid lesions but normal colonoscopy developed colorectal cancer during 3 years of observation (median observation time 7 years). Conclusions Incidental colorectal FDG uptake was infrequently observed, but when present, it was associated with a high rate of malignant or premalignant lesions. Our results indicate that patients with incidental colorectal FDG uptake should be referred to diagnostic work-up including colonoscopy.

Nuclear imaging methods for the prediction of postoperative morbidity and mortality in patients undergoing localized, liver-directed treatments: a systematic review.

BACKGROUND: Several nuclear imaging methods may predict postoperative liver function and outcome, but none has achieved recommendations in clinical guidelines. The purpose of this systematic review was to summarize the existing knowledge on this topic. METHODS: MEDLINE and Web of Science were searched for studies investigating nuclear medicine imaging methods for the prediction of postoperative liver function in patients undergoing localized, liver-directed treatments. The postoperative endpoints were clinical outcome (morbidity and mortality) as well as measures of postoperative liver function, e.g., liver function assessed by biochemical tests or nuclear imaging. RESULTS: A total of 1352 references were identified, of which 82 fulfilled the eligibility criteria and were included in the review. Most studies (n = 63) were retrospective studies. The vast majority of studies assessed [99mTc]Tc-galactosyl serum albumin (GSA) (n = 57) and [99mTc]Tc-mebrofenin (n = 19). Liver resection was entirely or partly major (involved at least three segments) in 78 reports. There were notable variations in the research methodology, e.g., image acquisition, imaging variables, and endpoints. Thirty-seven studies reported on postoperative mortality, of which most reported descriptive data at the patient level. Of the four reports that performed multivariate analyses, two showed significant predictive results of isotope-based preoperative tests. Fifty-two papers presented data on postoperative liver failure. Multivariate predictive analyses were performed in eighteen trials, of which fifteen showed the significant value of nuclear medicine tests. CONCLUSION: There is sparse evidence supporting the significant value of nuclear medicine imaging methods in predicting postoperative mortality. In contrast, a notable number of trials showed a significant prediction of liver failure in multivariate analyses. The research methodology was heterogeneous and exploratory in most trials. Documentation of nuclear medicine tests in this setting awaits the results of properly designed, prospective trials with the standardization of both the nuclear medicine test and endpoints.

Improvement in image quality of Tc-99m-based ventilation/perfusion single-photon emission computed tomography in patients with chronic obstructive pulmonary disease through pretest continuous positive airway pressure treatment.

Ventilation/perfusion single-photon emission computed tomography performed using an aerosol of carbon-coated technetium is frequently used for diagnosing pulmonary embolism. Certain patients may suffer from chronic obstructive pulmonary disease (COPD); for such patients, the formation of mucus clots in airways can cause accumulation of the aerosol in the larger airways. This centralized deposition of the aerosol leads to insufficient activity in peripheral lung segments and subsequently results in ventilation images of substandard or even nondiagnostic quality. Continuous positive airway pressure (CPAP) therapy improves airway dynamics and quality of life for COPD patients. We report for the first time the results for two patients for whom initial ventilation scans were of insufficient quality, but diagnostic-quality images were obtained after CPAP therapy.

Prospective comparative study of 18F-sodium fluoride PET/CT and planar bone scintigraphy for treatment response assessment of bone metastases in patients with prostate cancer.

AIM: To compare 18F-sodium fluoride positron emission tomography/computed tomography (NaF PET/CT) and 99mTc-labelled diphosphonate bone scan (BS) for the monitoring of bone metastases in patients with prostate cancer undergoing anti-cancer treatment. MATERIAL AND METHODS: Data from 64 patients with prostate cancer were included. The patients received androgen-deprivation therapy (ADT), next-generation hormonal therapy (NGH) or chemotherapy. The patients had a baseline scan and 1-3 subsequent scans during six months of treatment. Images were evaluated by experienced nuclear medicine physicians and classified for progressive disease (PD) or non-PD according to the Prostate Cancer Working Group 2 (PCWG-2) criteria. The patients were also classified as having PD/non-PD according to the clinical and prostate-specific antigen (PSA) responses. RESULTS: There was no difference between NaF PET/CT and BS in the detection of PD and non-PD during treatment (McNemar's test, p = .18). The agreement between BS and NaF PET/CT for PD/non-PD was moderate (Cohen's kappa 0.53, 95% confidence interval 0.26-0.79). Crude agreement between BS and NaF PET/CT for the assessment of PD/non-PD was 86% (89% for ADT, n = 28; 88% for NGH, n = 16, and 80% for chemotherapy, n = 20). In most discordant cases, BS found PD when NaF PET/CT did not, or BS detected PD on an earlier scan than NaF PET/CT. Biochemical progression (27%) occurred more frequently than progression on functional imaging (BS, 22% and NaF PET/CT, 14%). Clinical progression was rare (11%), and almost exclusively seen in patients receiving chemotherapy. CONCLUSION: There was no difference between NaF PET/CT and BS in the detection of PD and non-PD; however, BS seemingly detects PD by the PCWG-2 criteria earlier than NaF-PET, which might be explained by the fact that NaF-PET is more sensitive at the baseline scan.

Predictive Value of PET Response Combined with Baseline Metabolic Tumor Volume in Peripheral T-Cell Lymphoma Patients.

Peripheral T-cell lymphoma (PTCL) is a heterogeneous group of aggressive non-Hodgkin lymphomas with poor outcomes on current therapy. We investigated whether response assessed with PET/CT combined with baseline total metabolic tumor volume (TMTV) could detect early relapse or refractory disease. Methods: From 7 European centers, 140 patients with nodal PTCL who underwent baseline PET/CT were selected. Forty-three had interim PET (iPET) performed after 2 cycles (iPET2), 95 had iPET performed after 3 or 4 cycles (iPET3/4), and 96 had end-of-treatment PET (eotPET). Baseline TMTV was computed with a 41% SUVmax threshold, and PET response was reported using the Deauville 5-point scale. Results: With a median of 43 mo of follow-up, the 2-y progression-free survival (PFS) and overall survival (OS) were 51% and 67%, respectively. iPET2-positive patients (Deauville score ≥ 4) had a significantly worse outcome than iPET2-negative patients (P < 0.0001, hazard ratio of 6.8 for PFS; P < 0.0001, hazard ratio of 6.6 for OS). The value of iPET3/4 was also confirmed for PFS (P < 0.0001) and OS (P < 0.0001). The 2-y PFS and OS for iPET3/4-positive (n = 28) and iPET3/4-negative (n = 67) patients were 16% and 32% versus 75% and 85%, respectively. The eotPET results also reflected patient outcome. A model combining TMTV and iPET3/4 stratified the population into distinct risk groups (TMTV ≤ 230 cm3 and iPET3/4-negative [2-y PFS/OS, 79%/85%]; TMTV > 230 cm3 and iPET3/4-negative [59%/84%]; TMTV ≤ 230 cm3 and iPET3/4-positive [42%/50%]; TMTV > 230 cm3 and iPET3/4-positive [0%/18%]). Conclusion: iPET response is predictive of outcome and allows early detection of high-risk PTCL patients. Combining iPET with TMTV improves risk stratification in individual patients.

Diagnostic accuracy of imaging methods for the diagnosis of skeletal malignancies: A retrospective analysis against a pathology-proven reference.

OBJECTIVES: To examine the diagnostic accuracy of imaging modalities in skeletal tumours versus pathology reports. MATERIALS AND METHODS: Pathology reports of bone biopsies were compared to diagnostic imaging with X-ray, computed tomography (CT), magnetic resonance imaging (MRI), bone scintigraphy (BS), and (18)F-fluorodeoxyglucose positron emission tomography (FDG-PET/CT) performed within 6 months of biopsy. RESULTS: A total of 409 biopsies were included. Sensitivity and specificity were significantly different among the five modalities (p<0.0001). The sensitivity of MRI and PET/CT was better than CT, but CT had a better specificity than PET/CT. In general, these methods outperformed BS and X-ray. The sensitivity for osteolytic lesions varied significantly between modalities (p<0.0001), with MRI and PET/CT being more sensitive than CT. Differences in sensitivity were also observed in mixed lesions (p=0.0002) but not in osteosclerotic lesions. In spine lesions, MRI showed the best sensitivity followed by PET/CT and CT (p<0.0005 vs. MRI). There was no significant differences among non-spine lesions. CONCLUSIONS: MRI and FDG-PET/CT showed comparable diagnostic characteristics in general, in individual tumour types, and in different bone lesions and locations. Nominally, they outperformed CT in most situations. The diagnostic accuracy of X-ray and BS were notably inferior to other modalities.

Skin pH, atopic dermatitis, and filaggrin mutations.

BACKGROUND: The acidic pH of the skin plays a role in antimicrobial defense by regulating the bacterial skin flora and aspects of barrier. Filaggrin is a co-factor in maintaining a low skin pH because of its degradation into acidic amino acids. Accordingly, lack of filaggrin due to filaggrin mutations may influence skin pH. OBJECTIVE: We aimed to determine the epidermal pH in different groups stratified by filaggrin mutations and atopic dermatitis. Further, we investigated the changes in pH according to severity of mutational status among patients with dermatitis, irrespective of skin condition. METHODS: pH was measured with a multiprobe system pH probe (PH 905), and the study population was composed of 67 individuals, who had all been genotyped for 3 filaggrin mutations (R501X, 2282del4, R2447X). RESULTS: We found no clear pattern in relation to filaggrin mutation carrier status. Individuals with wild-type filaggrin displayed both the most acidic and most alkaline values independent of concomitant skin disease; however, no statistical differences between the groups were found. CONCLUSIONS: The lack of significant diversity in skin pH in relation to filaggrin mutation carrier status suggests that the effect of filaggrin mutations on skin pH is not pronounced.

Assessment of pain response in capsaicin-induced dynamic mechanical allodynia using a novel and fully automated brushing device.

BACKGROUND: Dynamic mechanical allodynia is traditionally induced by manual brushing of the skin. Brushing force and speed have been shown to influence the intensity of brush-evoked pain. There are still limited data available with respect to the optimal stroke number, length, force, angle and speed. Therefore, an automated brushing device (ABD) was developed, for which brushing angle and speed could be controlled to enable quantitative assessment of dynamic mechanical allodynia. OBJECTIVES: To compare the ABD with manual brushing using capsaicin-induced allodynia, and to investigate the role of stroke angle and speed on pain intensity. METHODS: Experimental dynamic mechanical allodynia was induced by an intradermal injection of capsaicin (100 µg) into the volar forearm of 12 healthy, male volunteers. Dynamic mechanical allodynia was rated on a 10 cm visual analogue scale (VAS) after each set of strokes at angles of 30°, 60° and 90° with speeds of 17 mm/s, 21 mm/s and 25 mm/s for each angle. A two-way ANOVA with repeated measures was performed to assess the influence of brushing parameters. To evaluate test-retest reliability, Bland-Altman 95% limits of agreement, including a coefficient of repeatability and an intraclass correlation coefficient (ICC), were determined. RESULTS: The angle and speed exhibited a significant impact on pain intensity (P<0.001 and P<0.015, respectively). Post hoc analysis showed that the highest pain intensity was recorded with an angle of 30° regardless of brushing speed. The ABD demonstrated superior test-retest reliability (coefficient of repeatability = 1.9 VAS; ICC=0.91) compared with manual brushing (coefficient of repeatability = 2.8 VAS; ICC=0.80; P<0.05). The most reliable combination of parameters (coefficient of repeatability = 1.3 VAS; ICC=0.97) was an angle of 60° and a speed of 21 mm/s. CONCLUSIONS: A controlled, automatic brushing method can be used for quantitative investigations of allodynic reactions, and is more reliable for quantitative assessment of dynamic mechanical allodynia compared with traditional manual brushing.

[Research in regional hospitals in two Danish regions]. / Forskning på regionshospitaler i Region Midtjylland og Region Nordjylland.

The quantity of interest, experience, and barriers to research in non-university hospitals in Denmark is undocumented. Therefore, a questionnaire was distributed to all employees at non-university hospitals in two Danish regions. The results showed that a substantial number of medical doctors were engaged in ongoing research. 24% of the respondents were supervisors in research projects, and 19% conducted contract research. Thus, Danish non-university hospitals have employees with both interest and experience in medical research. The four most commonly stated barriers for research were lack of time, funding, supervision, and training courses.

[A survey of research funding at Danish regional hospitals]. / Forskning ved regionale hospitalsenheder i Vestdanmark.

INTRODUCTION: According to recently passed Danish legislation, all Danish hospitals are obliged to take part in scientific research. As data on financial support for research activities are lacking, we assessed the resources allocated to research from the budget of the central hospital management as a percentage of the total budget at Danish regional hospitals in 2007. MATERIAL AND METHODS: A postal survey was conducted at 13 hospitals in the Western part of Denmark. The questionnaire comprised items in the following major categories: 1) budget allocated specifically for research and travel grants; 2) employment of scientific and technical support staff; 3) facilities and equipment for research; and 4) research dissemination. RESULTS: Questionnaires were returned from 11 hospitals. Six hospitals reported to have dedicated fixed amounts on the budget for research, exact figures were reported in four cases only equivalent to 0.1%, 0.3%, 0.3% and 0.6% of the total budget. Most hospitals had associate professors, but only five had full professors. Seven hospitals supplied laboratories and technical facilities, eight hospitals held staff-meetings on a regular basis and four published an annual report on research activities. CONCLUSION: In the majority of regional hospitals in Western Denmark, less than 0.3% of the total budget administered by the central hospital management was allocated specifically for research. These figures, however, may not be accurate as individual departments may allocate additional resources from local budgets. We recommend that regional hospitals define research strategies and allocate the necessary funding in their budgets.