Potential utility of myocardial blood flow quantification with single photon emission computed tomography in a patient undergoing treatment for breast cancer.

Diagnosis and management of cardiac complications of cancer treatment can be challenging. Few PET data suggest a potential role of dynamic perfusion imaging with measurements of absolute myocardial blood flow and flow reserve (MFR). We report the case of a 72-year-old woman with a history of bilateral breast cancer who underwent dynamic cardiac scintigraphy. Relative perfusion analysis was normal, whereas MFR was impaired in all territories suggesting diffuse microvascular dysfunction. Flow parameters derived from dynamic cardiac scintigraphy could thus be an interesting tool in cardio-oncology.

Regadenoson versus dipyridamole: Evaluation of stress myocardial blood flow response on a CZT-SPECT camera.

BACKGROUND: Regadenoson is a selective adenosine receptor agonist. It is currently unclear if the level of hyperemia differs between stress agents. We compared Myocardial Blood Flow (MBF) and Myocardial Flow Reserve (MFR) response on CZT-SPECT Myocardial Perfusion Imaging (MPI) to evaluate if dipyridamole and regadenoson could induce the same level of hyperemia. METHODS: 228 patients with dynamic CZT-SPECT MPI were retrospectively analyzed (66 patients stressed with regadenoson and 162 with dipyridamole) in terms of MBF and MFR. To rule out confounding factors, two groups of 41 patients were matched for clinical characteristics in a sub-analysis, excluding high cardiovascular risk patients. RESULTS: Overall stress MBF was higher in regadenoson patients (1.71 ± 0.73 vs. 1.44 ± 0.55 mL·min-1·g-1 for regadenoson and dipyridamole, respectively, p < .05). However, when confounding factors were ruled out, stress MBF (1.57 ± 0.56 vs. 1.61 ± 0.62 mL·min-1·g-1 for dipyridamole and regadenoson, respectively, p = .88) and MFR (2.62 ± 0.77 vs. 2.46 ± 0.76 for dipyridamole and regadenoson, respectively, p = .40) were not different between regadenoson and dipyridamole. CONCLUSIONS: Our results suggest that dipyridamole and regadenoson induce equivalent hyperemia in dynamic SPECT with similar stress MBF and MFR in comparable patients.

Impact of attenuation correction for CZT-SPECT measurement of myocardial blood flow.

OBJECTIVES: Most of cardiac dedicated CZT-SPECT systems are not equipped with CT, whereas PET systems are. We evaluated the impact of AC correction on CZT-SPECT myocardial blood flow (MBF) and myocardial flow reserve (MFR) measurements. METHODS: 104 patients were included. SPECT data were acquired on cadmium zinc telluride (CZT)-based pinhole cardiac camera in listmode using a stress (250 ± 17 MBq)/rest (511 ± 23 MBq) 1-day Tc-99m-tetrofosmin protocol. Low-dose CT was acquired on another SPECT/CT camera in the same position. All analysis was performed using Corridor4DM. RESULTS: Stress and rest MBF were significantly lower when AC was applied (P < 0.001). For regional and global MFR, there was no significant difference between AC and NAC measurements (P > 0.25 at least). Mean global LV MFR was 2.43 ± 0.87 and 2.33 ± 0.89, respectively, for NAC and AC measurements. Using a threshold of 2, 86 patients (83%) remained classified as normal and abnormal regarding global LV MFR whether AC was applied or not. Mean difference between NAC and AC values for the 18 other patients was 0.3. CONCLUSION: AC correction does not significantly affect MFR measurement both in regional and global LV analyses.

Assessing the Parasitic Burden in a Late Antique Florentine Emergency Burial Site.

Excavation (2008-2014) carried out under the Uffizi Gallery (Florence, Italy) led to the discovery of 75 individuals, mostly buried in multiple graves. Based on Roman minted coins, the graves were preliminarily dated between the second half of the 4th and the beginning of the 5th centuries CE. Taphonomy showed that this was an emergency burial site associated with a catastrophic event, possibly an epidemic of unknown etiology with high mortality rates. In this perspective, paleoparasitological investigations were performed on 18 individuals exhumed from 9 multiple graves to assess the burden of gastrointestinal parasitism. Five out of eighteen individuals (27.7%) tested positive for ascarid-type remains; these are considered as "decorticated" Ascaris eggs, which have lost their outer mammillated coat. Roundworms (genus Ascaris) commonly infest human populations under dire sanitary conditions. Archaeological and historical evidence indicates that Florentia suffered a period of economic crisis between the end of 4th and the beginning of the 5th centuries CE, and that the aqueduct was severely damaged at the beginning of the 4th century CE, possibly during the siege of the Goths (406 CE). It is more than plausible that the epidemic, possibly coupled with the disruption of the aqueduct, deeply affected the living conditions of these individuals. A 27.7% frequency suggests that ascariasis was widespread in this population. This investigation exemplifies how paleoparasitological information can be retrieved from the analysis of sediments sampled in cemeteries, thus allowing a better assessment of the varying frequency of parasitic infections among ancient populations.

Paleoparasitology of Merovingian Corpses Buried in Stone Sarcophagi in the Saint-Martin-au-Val Church (Chartres, France).

Paleoparasitological analysis was carried on 4 Merovingian skeletons, dated from the late-5th to the late-9th centuries, and recovered in the church of Saint-Martin-au-Val in Chartres (Center region, France). The corpses were buried in stone sarcophagi, which were still sealed at the time of excavation. Parasite marker extraction was conducted on sediment samples taken from the abdominal and pelvic regions, but also on samples taken from under the head and the feet as control samples. Microscopic observation revealed the presence of 3 gastrointestinal parasites, namely the roundworm (Ascaris lumbricoides), the whipworm (Trichuris trichiura) and the fish tapeworm (genus Diphyllobothrium). This analysis contributes to a better knowledge of the health status and the lifestyle of ancient medieval populations during the Merovingian period, for which very few paleoparasitological data were available, up until now. It demonstrates the presence of the fish tapeworm for the first time during this period.

Palaeoparasitology and palaeogenetics: review and perspectives for the study of ancient human parasites.

While some species of parasites can be identified to species level from archaeological remains using microscopy (i.e. Enterobius vermicularis, Clonorchis sinensis), others can only be identified to family or genus level as different species produce eggs with similar morphology (i.e. Tænia sp. and Echinococcus sp.). Molecular and immunological approaches offer the possibility to provide more precise determination at the species level. They can also identify taxa when classic parasite markers such as eggs or cysts have been destroyed over time. However, biomolecules can be poorly preserved and modern reference DNA is available only for a limited number of species of parasites, leading to the conclusion that classic microscopic observation should be combined with molecular analyses. Here we present a review of the molecular approaches used over the past two decades to identify human pathogenic helminths (Ascaris sp., Trichuris sp., E. vermicularis, Fasciola sp. etc.) or protists (Giardia sp., Trypanosoma sp., Leishmania sp. etc.). We also discuss the prospects for studying the evolution of parasites with genetics and genomics.

A First Case of Human Trichuriasis from a Roman Lead Coffin in France.

A paleoparasitological study was carried out on 2 lead coffins recovered from the Roman site of Jaunay-Clan (near Poitiers, France). For the first time, this particular type of burial gave positive parasitological results, and eggs of the whipworm Trichuris trichiura were identified in 1 individual. In the present case, thanatomorphose associated with funerary practices may explain the scarcity of the recovered eggs. However, human whipworm has now been observed in 9 individuals dated to the Roman period. The very high frequency of Trichuris sp. eggs in Roman archaeological sites (up to 80%) suggests that fecal peril, hygiene, and waste management were problematic during this period. Finally, due to the fact that very few analyses have been conducted on human bodies dated to the Roman period, more analyses must be performed in the future to provide further information about diseases in the Roman world.

Viruses in a 14th-century coprolite.

Coprolites are fossilized fecal material that can reveal information about ancient intestinal and environmental microbiota. Viral metagenomics has allowed systematic characterization of viral diversity in environmental and human-associated specimens, but little is known about the viral diversity in fossil remains. Here, we analyzed the viral community of a 14th-century coprolite from a closed barrel in a Middle Ages site in Belgium using electron microscopy and metagenomics. Viruses that infect eukaryotes, bacteria, and archaea were detected, and we confirmed the presence of some of them by ad hoc suicide PCR. The coprolite DNA viral metagenome was dominated by sequences showing homologies to phages commonly found in modern stools and soil. Although their phylogenetic compositions differed, the metabolic functions of the viral communities have remained conserved across centuries. Antibiotic resistance was one of the reconstructed metabolic functions detected.

Comprehensive literature review of oral and intravenous contrast-enhanced PET/CT: a step forward?

The integration of diagnostic CT scans into PET/CT facilitates a comprehensive single examination, presenting potential advantages for patients seeking a thorough one-shot check-up. The introduction of iodinated contrast media during PET scanning raises theoretical concerns about potential interference with uptake quantification, due to the modification of tissue density on CT. Nevertheless, this impact appears generally insignificant for clinical use, compared to the intrinsic variability of standardized uptake values. On the other hand, with the growing indications of PET, especially 18F-FDG PET, contrast enhancement increases the diagnostic performances of the exam, and provides additional information. This improvement in performance achieved through contrast-enhanced PET/CT must be carefully evaluated considering the associated risks and side-effects stemming from the administration of iodinated contrast media. Within this article, we present a comprehensive literature review of contrast enhanced PET/CT, examining the potential impact of iodinated contrast media on quantification, additional side-effects and the pivotal clinically demonstrated benefits of an all-encompassing examination for patients. In conclusion, the clinical benefits of iodinated contrast media are mainly validated by the large diffusion in PET protocols. Contrary to positive oral contrast, which does not appear to offer any major advantage in patient management, intravenous iodine contrast media provides clinical benefits without significant artifact on images or quantification. However, studies on the benefit-risk balance for patients are still lacking.

Osteonecrosis of the Femoral Head as a Potential Pitfall in 18 F-PSMA-1007 PET.

ABSTRACT: PSMA-targeted PET agents are mainly involved for prostate cancer; however, unspecific bone uptakes can be challenging for the clinician. We report the case of a 71-year-old man with history of recurrent prostate cancer initially treated by surgery and radiation therapy. 18 F-PSMA 1007 PET/CT was performed. Beside hyperfixing lymph nodes, focal uptake was found in right femoral head with shell subchondral hypofixation and no morphologic correlate on CT. MRI found bilateral osteonecrosis of the femoral head. This case emphasizes that osteonecrosis of the femoral head can mimic a metastasis uptake, even with normal CT, without however the fixation being constant.

3D-Ring CZT System With New Low- and Medium-Energy Range: Ultrafast Dual-Isotope Lung SPECT/CT Improvement.

ABSTRACT: New 3D-ring CZT systems with low- and medium-energy-range detectors allow for simultaneous dual-isotope lung scintigraphy. We compared 10-, 7-, 5-, and 3-minute acquisitions for 99m Tc and 81m Kr performed simultaneously on StarGuide CZT-SPECT/CT and reframed in 50 patients. Ventilation/perfusion mismatches were calculated (mean, 15.6% ± 28%), and Spearman correlation coefficients of mismatches were 0.994, 0.994, and 0.984 between 10- and 7-, 5-, and 3-minute acquisitions, respectively. No visual difference in image quality or final diagnosis was found. 3D-ring CZT-SPECT with low and medium energy range detectors allows ultrafast dual-isotope lung scintigraphy up to 3 minutes.

Extinction of Lipomatous Hypertrophy of the Interatrial Septum FDG Uptake With Propranolol Premedication.

ABSTRACT: Lipomatous hypertrophy of the interatrial septum is a rare lesion of the heart. CT and cardiac MR are often sufficient to determine the benign lipomatous nature of the tumor and can avoid the need for histological confirmation. Lipomatous hypertrophy of the interatrial septum contains variable amounts of brown adipose tissue, resulting in different degrees of 18 F-FDG uptake in PET. We report the case of a patient with an interatrial lesion suspected of malignancy, discovered on CT and failing cardiac MR, with initial 18 F-FDG uptake. Final characterization was made thanks to 18 F-FDG PET with ß-blocker premedication, avoiding an invasive procedure.

Dynamic CZT-SPECT: Characterizing the Lower Values of Myocardial Blood Flow and Reserve.

ABSTRACT: CZT-SPECT myocardial perfusion enables quantification of myocardial blood flow (MBF). Normal values and thresholds have been accurately defined in PET but remain unclear in SPECT. The aim of this study was to report normal MBF and myocardial flow reserve values in very low-risk patients referred for coronary artery disease screening with dynamic SPECT, in comparison with patients experiencing coronary artery disease. Eighty-four patients (31 male) were analyzed. The mean 10 years risk of fatal cardiovascular events score was 2.7% ± 1.4%. The mean global stress MBF and myocardial flow reserve were 1.6 ± 0.6 mL/min/g and 2.7 ± 0.7.

Precision of Myocardial Blood Flow and Flow Reserve Measurement During CZT SPECT Perfusion Imaging Processing: Intra- and Interobserver Variability.

The aim of this study was to evaluate the reproducibility of myocardial blood flow (MBF) and myocardial flow reserve (MFR) measurement in patients referred for dynamic SPECT. Methods: We retrospectively analyzed patients referred for myocardial perfusion imaging. SPECT data were acquired on a cadmium zinc telluride-based pinhole cardiac camera in list mode using a stress (251 ± 15 MBq)/rest (512 ± 26 MBq) 1-d 99mTc-tetrofosmin protocol. Kinetic analyses were done with software using a 1-tissue-compartment model and converted to MBF using a previously determined extraction fraction correction. MFR was analyzed and compared globally and regionally. Motion detection was applied, but not attenuation correction. Results: In total, 124 patients (64 male, 60 female) were included, and SPECT acquisitions were twice reconstructed by the same nuclear medicine board-certified physician for 50 patients and by 2 different physicians for 74. Both intra- and interobserver measurements of global MFR had no significant bias (-0.01 [P = 0.94] and 0.01 [P = 0.67], respectively). However, rest MBF and stress MBF were significantly different in global left ventricular evaluation (P = 0.001 and P = 0.002, respectively) and in the anterior territory (P < 0.0001) on interuser analysis. The average coefficient of variation was 15%-30% of the mean stress MBF if the analysis was performed by the same physician or 2 different physicians and was around 20% of the mean MFR independently of the processing physician. Using the MFR threshold of 2, we noticed good intrauser agreement, whereas it was moderate when the users were different (κ = 0.75 [95% CI, 0.56-0.94] vs. 0.56 [95% CI, 0.36-0.75], respectively). Conclusion: Repeated measurements of global MFR by the same physician or 2 different physicians were similar, with an average coefficient of variation of 20%. Better reproducibility was achieved for intrauser MBF evaluation. Automation of processing is needed to improve reproducibility.

From modern-day parasitology to paleoparasitology: the elusive past record and evolution of Cryptosporidium.

Recent efforts have been made to review the state of the art on a variety of questions and targets in paleoparasitology, including protozoan taxa. Meanwhile, these efforts seemed to let aside Cryptosporidium, and we then intended to review its paleoparasitological record to assess its past distribution and favored detection methods, and eventually highlight needed research trajectories. This review shows that contrary to other parasites, most of the positive results came from South-American sites and coprolites rather than sediment samples, highlighting the need to test this kind of material, notably in Europe where many negative results were reported in the published literature from sediment samples. Moreover, aDNA-based detections are nearly absent from the paleoparasitological record of this parasite, though punctually shown successful. With their potential to address the evolutionary history of Cryptosporidium species, notably through their 18S rRNA tree, aDNA-based approaches should be encouraged in the future. In sum, and though the limits of currently used methods and materials remain unclear, this review highlights the potential role of coprolites and aDNA for the study of Cryptosporidium species in the past and how this history shaped their current diversity and distribution, notably among human populations but also farm animals.

Implications of the prevalence of Ascaris sp. in the funerary context of a Late Antique population (5th-7th c.) in Granada (Spain).

OBJECTIVE: To evaluate the prevalence of gastro-intestinal parasites in human remains from Late Antiquity (5th - 7th c.) Granada (Spain). MATERIALS: The study included pelvic and cranial control samples from 17 skeletons from the archaeological sites of Los Mondragones (n = 13) and Rafael Guillén (n = 4). METHODS: In the paleoparasitological study, soil samples from pelvic area and cranium were analyzed using the rehydration, homogenization, and micro-sieving method and visualization under brightfield microscopy. RESULTS: Ascaris sp. eggs were detected in pelvic samples from seven individuals. CONCLUSIONS: These findings may indicate that this parasite was endemic. Its detection frequency is one of the highest reported at group level in an osteological series from Late Antiquity. SIGNIFICANCE: The prevalence of Ascaris sp. associated with skeletal remains has implications for assessing the lifestyle and health of populations in southern Spain during the Late Antique period. LIMITATIONS: The number of individuals is small and taphonomic processes could have limited paleoparasitological findings SUGGESTIONS FOR FURTHER RESEARCH: Future interdisciplinary studies of this type are warranted in larger osteological series to improve knowledge of parasitosis in the past.