Highlights • Objective IQ for T2WI was at 1.5T under optimized parameters comparable to 3T. • SNR and CNR of DWI were significantly higher at 3T. • Subjective IQ on was significantly better at 3T. • ...PI-RADS v2 scores were similar at 3T and 1.5T.
Purpose
This study evaluates the feasibility of performing less than two core biopsies per MRI-lesion when performing targeted MR-guided in-bore prostate biopsy.
Methods
Retrospectively evaluated ...were 1545 biopsy cores of 774 intraprostatic lesions (two cores per lesion) in 290 patients (66 ± 7.8 years; median PSA 8.2 ng/ml) regarding prostate cancer (PCa) detection, Gleason score, and tumor infiltration of the first (FBC) compared to the second biopsy core (SBC). Biopsies were acquired under in-bore MR-guidance.
Results
For the biopsy cores, 491 were PCa positive, 239 of 774 (31 %) were FBC and 252 of 771 (33 %) were SBC (
p
= 0.4). Patient PCa detection rate based on the FBC vs. SBC were 46 % vs. 48 % (
p
= 0.6). For clinically significant PCa (Gleason score ≥4 + 3 = 7) the detection rate was 18 % for both, FBC and SBC (
p
= 0.9). Six hundred and eighty-seven SBC (89 %) showed no histologic difference. On the lesion level, 40 SBC detected PCa with negative FBC (7.5 %). Twenty SBC showed a Gleason upgrade from 3 + 3 = 6 to ≥3 + 4 = 7 (2.6 %) and 4 to ≥4 + 3 = 7 (0.5 %).
Conclusion
The benefit of a second targeted biopsy core per suspicious MRI-lesion is likely minor, especially regarding PCa detection rate and significant Gleason upgrading. Therefore, a further reduction of biopsy cores is reasonable when performing a targeted MR-guided in-bore prostate biopsy.
Key Points
•
Higher PI-RADS overall score (IV-V) correlated well with PCa detection rate
•
In more than 80 % SBC was concordant regarding overall PCa detection
•
In almost 90 % there was no Gleason upgrading by the SBC
•
Only 2/54 (3.7 %) csPCa was missed when the SBC was omitted
•
For IB-GB a further reduction of biopsy cores is reasonable
•Objective IQ for T2WI was at 1.5T under optimized parameters comparable to 3T.•SNR and CNR of DWI were significantly higher at 3T.•Subjective IQ on was significantly better at 3T.•PI-RADS v2 scores ...were similar at 3T and 1.5T.
This study prospectively evaluates objective image quality (IQ), subjective IQ, and PI-RADS scoring of prostate MRI at 3.0T (3T) and 1.5T (1.5T) within the same patients.
Sixty-three consecutive patients (64±9years) were prospectively included in this non-inferiority trial, powered at 80% to demonstrate a ≤10% difference in signal-to-noise (SNR) and contrast-to-noise ratio (CNR) of T2-weighted and diffusion-weighted imaging (T2WI, DWI) at 1.5T compared to 3T. Secondary endpoints were analysis of subjective IQ and PI-RADS v2 scoring.
All patients received multi-parametric prostate MRI on a 3T (T2WI, DWI, DCE) and bi-parametric MRI (T2WI, DWI) on a 1.5T scanner using body coils, respectively. SNR and CNR of T2WI were similar at 1.5T and 3T (p=0.7–1), but of DWI significantly lower at 1.5T (p<0.01). Subjective IQ was significantly better at 3T for both, T2WI and DWI (p<0.01). PI-RADS scores were comparable for both field strengths (p=0.05–1). Inter-reader agreement was excellent for subjective IQ assessment and PI-RADS scoring (k=0.9–1).
Prostate MRI at 1.5T can reveal comparable objective image quality in T2WI, but is inferior to 3T in DWI and subjective IQ. However, similar PI-RADS scoring and thus diagnostic performance seems feasible independent of the field strength even without an endorectal coil.
The Zagros foreland basin is an important sedimentary archive for the tectonic and paleoclimatic evolution of the Zagros Mountains and the entire Neotethyan Arabia–Iran collision zone. By combining ...new geochemical high‐resolution whole rock XRF data with clay mineralogy and soluble salt geochemistry we propose an evolution of the sedimentary environment in the Lurestan arc from the Serravallian to the early Pleistocene, closing a gap in understanding the complex exhumation history of the central Zagros mountain belt. An increase in ultramafic sedimentary input indicates a shift from provenance 1 to provenance 2 by ophiolite exhumation at ca.10 Ma in the Imbricated Zagros north of the Lurestan arc. Our data further indicates that the sedimentary environment of parts of the Lahbari Mb within the Lurestan arc represents a piedmont deposition of fine‐grained alluvial fans and siltstones with aeolian contribution deposited under hyper‐arid climate conditions. These represent provenance shift 3 and were likely sourced from evaporites of the underlying Gachsaran Fm and fluvial deposits of the Lower Aghajari Mb (provenance 1 and provenance 2), uplifted by the Mountain Front Flexure at around 5.6 Ma. Combining XRF whole rock data with clay mineral data refines formation conditions of the clay minerals in the foreland basin such as palygorskite, which is revealed to be authigenic in origin in the Lower Aghajari Mb. as a function of varying Mg‐content due to variations of erosion of the ultramafic and mafic rocks in the Imbricate Zagros belt. Palygorskite in the Lahbari Member is likely both inherited from the Neogene Gachsaran evaporites as well as of authigenic origin.
Y/Ni versus Cr/V diagram (Hiscott, 1984) as an indicator of ultramafic input for samples from the Gachsaran Fm, the Lower Aghajari Mb and the Lahbari Mb UM‐ultramafic, GR‐granitic, ME‐metamorphic endmembers and mixing hyperboles modified from Dinelli et al. (1999).
The Zagros Mountain belt in Iran comprises an extensive record of Mesozoic and Cenozoic deposits uplifted by collision of the Arabian and Iranian continental plates. This area has been shown to ...provide important information to decipher the climatic history of Western Asia, especially regarding the evolution of deserts in Mesopotamia and Northern Arabia. In a high-resolution geological record of 84 samples, we combine clay mineralogy and micropalaeontological observations to refine the late Neogene climate record in Northern Arabia. We investigated a 2.6-km-thick sedimentary profile from the Simply Folded Zagros Mountain belt spanning ca. 10.2 myrs from the late Middle Miocene (Serravallian) to earliest Pleistocene (Gelasian) comprising floodplain sediments and saline mudstones with a strong aeolian contribution. The clay fraction < 2 µm reveals palygorskite, smectite, illite, chlorite and the zeolite mineral erionite. Using clay mineralogy, arid conditions during the Serravallian and early Tortonian in Northern Arabia are identified, followed by semi-arid conditions during the late Tortonian. Clay mineralogy suggests a transition to sustained arid conditions during the early Messinian and provides a more complex picture on a previously proposed period of hyperaridity (NADX) in Northern Arabia penecontemporaneous with the apex of the Messinian salinity crisis.
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•Carbonatites of the Fen complex experienced intense hydrothermal alteration.•The first alteration event (pyritization) caused the crystallization of sulphides.•Carbonatite-derived ...fluids caused remobilization of REE, Ti, Th, Nb, Fe and Al.
We present detailed textural and chemical analyses of the hydrothermal sulfide- and REE-Th-Nb-mineralization observed in the Fen complex (southern Norway), which is the biggest carbonatite-related REE and Th deposit in Europe. The alkaline silicate rocks and carbonatites of the Fen complex underwent two hydrothermal alteration events that caused (i) the formation of sulfides and (ii) (re)-mobilization of REE, Fe and Al. This renders the Fen complex an ideal locality to study the genesis of hydrothermal sulfide and REE mineralization in carbonatites. Our observations record a hydrothermal alteration history of the Fen carbonatite complex, which is relevant to many carbonatite complexes worldwide.
The first alteration event (pyrite-stage) caused the crystallization of sulfides (mostly pyrite) in all lithologies and was induced by a sulfide-rich fluid 1 that was probably derived from adjacent mafic alkaline silicate rocks. Veins formed during this hydrothermal event show a typical succession from magnetite via pyrite I + hematite + magnetite to pyrite II.
A subsequent alteration event is characterized by the interaction of two evolving fluids, namely (1) a REE-rich fluid 2 that was probably derived from the carbonatites (autometasomatic fluid) and (2) an oxidizing meteoric fluid 3 that mainly introduced Si and was in equilibrium with the basement host rocks. The interaction of these two fluids with the carbonatitic rocks resulted in various characteristic types of calcite-hematite rocks locally called rødberg. During their late-stage silicification by fluid 3, P was mobilized from magmatic apatite and reprecipitated in close-by rødberg veins as small fluorapatite-monazite veins.
The interaction of the carbonatite-derived fluid 2 and meteoric fluid 3 also resulted in the formation of distinct zones of LREE-phases, notably REE-F-carbonates (bastnäsite, parisite, synchysite), monazite and allanite, and HREE-phases (including samarskite, aeschynite and an unnamed Nb-Fe-REE-Th-oxide. The most pronounced HREE-enrichment occurs in domains of strongest hydrothermal alteration, which was probably caused by preferential precipitation of HREE-rich complexes coupled with later partial leaching of LREE by F-rich fluids during silicification. Thorium-rich minerals were precipitated in close association with HREE-rich minerals implying similar hydrothermal behaviour of Th and HREE.
