Cognitive performance changes in chronic kidney disease patients related to cardiovascular risc factors and diseases over a 2-year-follow-up

Einleitung. Viele Patienten mit einer chronischen Nierenerkrankung (CKD) weisen kognitive Defizite und gleichzeitig kardiovaskuläre Risikofaktoren und Erkrankungen auf. Wie sich die kognitive Leistung bei CKD-Patienten im zeitlichen Verlauf ändert und welche Rolle dabei kardiovaskuläre Risikofaktoren und Erkrankungen spielen, ist bislang unklar. Methode. In unserer Studie wurden 120 Probanden (73 Patienten mit CKD, Stadium 3-5D, Alter 64,3 ± 13,6 Jahre und 47 Kontrollpatienten mit vergleichbaren kardiovaskulären Risikofaktoren und Erkrankungen, Alter 62,6 ± 10,2 Jahre) im Rahmen der Studie „New Tools for the Prevention of Cardiovascular Disease in Chronic Kidney Disease“ (NTCVD) bei Baseline und nach 2 Jahren untersucht. Die Nierenfunktion wurde anhand von eGFR beurteilt. Die neuropsychologische Untersuchung bestand aus zehn Tests, die fünf kognitive Bereiche erfassten. Ergebnisse. Die Nierenfunktion, kardiovaskuläre Risikofaktoren und Erkrankungen sowie kognitive Leistungen blieben innerhalb von 2 Jahren in den beiden Patientengruppen sehr stabil. Der Summenwert für globale kognitive Leistung veränderte sich von Baseline (BL) zum Follow-up (FU) in den beiden Patientengruppen nahezu nicht (z = -0,63 ± 0,76 bei BL vs. z = -0,54 ± 0,79 bei FU, p = 0,113 für CKD-Patienten; z = -0,01 ± 0,59 bei BL vs. z = 0,01 ± 0,70 bei FU, p = 0,862 für Kontrollpatienten). Es gab eine signifikante Verbesserung im kognitiven Bereich „Sprache“ bei CKD-Patienten (z = -0,61 ± 0,85 bei BL vs. z = 0,41 ± 0,94 bei FU, p = 0,008). Das Gesamtcholesterin verringerte sich in den beiden Patientengruppen innerhalb des Untersuchungszeitraums signifikant, die Intima-Media-Dicke nahm in der CKD-Gruppe signifikant ab. Die wichtigsten Prädiktoren für eine Verschlechterung bzw. geringere Verbesserung der globalen kognitiven Leistung in multivariablen Regressionsanalysen waren hohes Alter und hohe kognitive Leistung zum Zeitpunkt der Baseline. Diskussion. In der NTCVD-Kohorte, die engmaschig untersucht und optimal behandelt wurde, trat keine kognitive Verschlechterung innerhalb von 2 Jahren auf. Unsere Daten betonten die Bedeutung der Auswahl einer geeigneten Kontrollgruppe mit kardiovaskulären Risikofaktoren. Außerdem erlaubten unsere Ergebnisse anzunehmen, dass bei einer optimalen medizinischen Behandlung von CKD-Patienten eine kognitive Verschlechterung im Erkrankungsverlauf vermieden werden könnte

Pseudorandom Selective Excitation in NMR

In this work, average Hamiltonian theory is used to study selective excitation in a spin-1/2 system evolving under a series of small flip-angle $\theta-$pulses $(\theta\ll 1)$ that are applied either periodically [which corresponds to the DANTE pulse sequence] or aperiodically. First, an average Hamiltonian description of the DANTE pulse sequence is developed; such a description is determined to be valid either at or very far from the DANTE resonance frequencies, which are simply integer multiples of the inverse of the interpulse delay. For aperiodic excitation schemes where the interpulse delays are chosen pseudorandomly, a single resonance can be selectively excited if the $\theta$-pulses' phases are modulated in concert with the time delays. Such a selective pulse is termed a pseudorandom-DANTE or p-DANTE sequence, and the conditions in which an average Hamiltonian description of p-DANTE is found to be similar to that found for the DANTE sequence. It is also shown that averaging over different p-DANTE sequences that are selective for the same resonance can help reduce excitations at frequencies away from the resonance frequency, thereby improving the apparent selectivity of the p-DANTE sequences. Finally, experimental demonstrations of p-DANTE sequences and comparisons with theory are presented.Comment: 23 pages, 8 figure

The assessment of left ventricular mechanical dyssynchrony from gated 99mTc-tetrofosmin SPECT and gated 18F-FDG PET by QGS: a comparative study

BACKGROUND Due to partly conflicting studies, further research is warranted with the QGS software package, with regard to the performance of gated FDG PET phase analysis as compared to gated MPS as well as the establishment of possible cut-off values for FDG PET to define dyssynchrony. METHODS Gated MPS and gated FDG PET datasets of 93 patients were analyzed with the QGS software. BW, Phase SD, and Entropy were calculated and compared between the methods. The performance of gated PET to identify dyssynchrony was measured against SPECT as reference standard. ROC analysis was performed to identify the best discriminator of dyssynchrony and to define cut-off values. RESULTS BW and Phase SD differed significantly between the SPECT and PET. There was no significant difference in Entropy with a high linear correlation between methods. There was only moderate agreement between SPECT and PET to identify dyssynchrony. Entropy was the best single PET parameter to predict dyssynchrony with a cut-off point at 62%. CONCLUSION Gated MPS and gated FDG PET can assess LVMD. The methods cannot be used interchangeably. Establishing reference ranges and cut-off values is difficult due to the lack of an external gold standard. Further prospective research is necessary

Response to 225Ac-PSMA-I&T after failure of long-term 177Lu-PSMA RLT in mCRPC

Purpose!#!With the spread of transjugular intrahepatic portosystemic shunts (TIPS), portosystemic shunt surgery (PSSS) has decreased and leaves more complex patients with great demands for accurate preoperative planning. The aim was to evaluate the role of imaging for predicting the most suitable PSSS approach.!##!Material and methods!#!Forty-four patients who underwent PSSS (2002 to 2013) were examined by contrast-enhanced CT (n = 33) and/or MRI (n = 15) prior to surgery. Imaging was analyzed independently by two observers (O1 and O2) with different levels of experience (O1 > O2). They recommended two shunting techniques (vessels and anastomotic variant) for each patient and ranked them according to their appropriateness and complexity. Findings were compared with the actually performed shunt procedure and its outcome.!##!Results!#!The first two choices taken together covered the performed PSSS regarding vessels in 88%/100% (CT/MRI, O1) and 76%/73% (O2); and vessels + anastomosis in 79%/73% (O1) and 67%/60% (O2). The prediction of complex surgical procedures (resection of interposing structures, additional thrombectomy, use of a collateral vessel, and use of a graft interposition) was confirmed in 87%, resulting in 80% sensitivity and 96% specificity. Larger shunt vessel distances were associated with therapy failure (p = 0.030) and a vessel distance of ≥ 20 mm was identified as optimal cutoff, in which a graft interposition was used. There was no significant difference between MRI and CT in predicting the intraoperative decisions (p = 0.294 to 1.000).!##!Conclusion!#!Preoperative imaging and an experienced radiologist can guide surgeons in PSSS. CT and MRI provide the information necessary to identify technically feasible variants and complicating factors

Initial Evaluation of Therapy Response after Adjuvant Radioiodine Therapy in Patients with Early-Stage Papillary Thyroid Cancer-Does Time Matter?

Simple Summary In recent years, there has been a clear trend toward personalized therapy procedures in patients with thyroid cancer with the aim to avoid unnecessary overtreatment of patients and to ensure an improved quality of life. We confirmed that early diagnostic control at 6 months after initial radioiodine therapy shows no significant disadvantages compared to a delayed control after 9 months. Further, it was observed that patients stimulated by hormone withdrawal before radioiodine therapy had significantly better outcomes compared to patients stimulated exogenously with recombinant human thyroid-stimulating hormone (rhTSH). However, early diagnostic control after TSH stimulation represents the most balanced solution for the patient, specifically regarding hypothyroidism symptoms after hormone withdrawal. Background: The aim was to assess ablation success after initial radioiodine (RAI) therapy in early-stage PTC patients and compare outcomes of first diagnostic control after 6 and 9 months (6m/9m-DC) to examine whether time could possibly avoid unnecessary overtreatment. Methods: There were 353 patients who were matched regarding age, sex, and tumor stage and divided in two groups depending on time of first DC (6m- and 9m-DC). Therapy response was defined as thyroglobulin level <0.5 ng/mL, no pathological uptake in the diagnostic I-131 whole-body scintigraphy (WBS), and no further RAI therapy courses. The 6m-DC group was further divided into endogenously and exogenously stimulated TSH before RAI therapy and compared regarding outcome. Results: No significant differences were found between 6m-DC vs. 9m-DC regarding I-131 uptake in WBS (p = n.s.), Tg levels (p = n.s.), re-therapy rates (p = n.s.), and responder rates (p = n.s.). Significantly less relevant pathological I-131 uptake was found in WBS (p = 0.006) in endogenously compared to exogenously stimulated 6m-DC patients, resulting in lower re-therapy (p = 0.028) and higher responder rates (p = 0.001). Conclusion: DC at 6 months after RAI therapy and stimulation with recombinant human thyroid-stimulating hormone (rhTSH) represent the most balanced solution. Particularly regarding quality of life and mental relief of patients, early DC with rhTSH represents sufficient and convenient assessment of ablation success

Quantitative myocardial perfusion SPECT/CT for the assessment of myocardial tracer uptake in patients with three-vessel coronary artery disease: Initial experiences and results

BACKGROUND To evaluate quantitative myocardial perfusion SPECT/CT datasets for routine clinical reporting and the assessment of myocardial tracer uptake in patients with severe TVCAD. METHODS MPS scans were reconstructed as quantitative SPECT datasets using CTs from internal (SPECT/CT, Q_INT) and external (PET/CT, Q_EXT) sources for attenuation correction. TPD was calculated and compared to the TPD from non-quantitative SPECT datasets of the same patients. SUVmax, SUVpeak, and SUVmean were compared between Q_INT and Q_EXT SPECT datasets. Global SUVmax and SUVpeak were compared between patients with and without TVCAD. RESULTS Quantitative reconstruction was feasible. TPD showed an excellent correlation between quantitative and non-quantitative SPECT datasets. SUVmax, SUVpeak, and SUVmean showed an excellent correlation between Q_INT and Q_EXT SPECT datasets, though mean SUVmean differed significantly between the two groups. Global SUVmax and SUVpeak were significantly reduced in patients with TVCAD. CONCLUSIONS Absolute quantification of myocardial tracer uptake is feasible. The method seems to be robust and principally suitable for routine clinical reporting. Quantitative SPECT might become a valuable tool for the assessment of severe coronary artery disease in a setting of balanced ischemia, where potentially life-threatening conditions might otherwise go undetected

Evolution of Neuropsychological Deficits in First-Ever Isolated Ischemic Thalamic Stroke and Their Association With Stroke Topography: A Case-Control Study.

BACKGROUND The thalamus plays an essential role in cognition. Cognitive deficits have to date mostly been studied retrospectively in chronic thalamic stroke in small cohorts. Studies prospectively evaluating the evolution of cognitive deficits and their association with thalamic stroke topography are lacking. This knowledge is relevant for targeted patient diagnostics and rehabilitation. METHODS Thirty-seven patients (57.5±17.5 [mean±SD] years, 57% men) with first-ever acute isolated ischemic stroke covering the anterior (n=5), paramedian (n=12), or inferolateral (n=20) thalamus and 37 in-patient controls without stroke with similar vascular risk factors matched for age and sex were prospectively studied. Cognition was evaluated using predefined tests at 1, 6, 12, and 24 months. Voxel-based lesion-symptom mapping was used to determine associations between neuropsychological deficits and stroke topography. RESULTS Patients with anterior thalamic stroke revealed severe deficits in verbal memory (median T score [Q1-Q3]: 39.1 [36.1-44.1]), language (31.8 [31.0-43.8]), and executive functions (43.8 [35.5-48.1]) at 1 month compared with controls (verbal memory: 48.5 [43.6-61.0], language: 55.7 [42.3-61.1], executive functions: 51.3 [50.1-56.8]). Patients with paramedian thalamic stroke showed moderate language (44.7 [42.8-55.9]) and executive (49.5 [44.3-55.1]) deficits and no verbal memory deficits (48.1 [42.5-54.7]) at 1 month compared with controls (59.0 [47.0-64.5]; 59.6 [51.1-61.3]; 52.5 [44.2-55.3]). The language and executive deficits in paramedian thalamic stroke patients almost completely recovered during follow-up. Intriguingly, significant deficits in verbal memory (44.7 [41.5-51.9]), language (47.5 [41.8-54.1]), and executive functions (48.2 [46.2-59.7]) were found in inferolateral thalamic stroke patients at 1 month compared with controls (50.5 [46.7-59.9]; 57.0 [51.2-62.9]; 57.4 [51.2-60.7]). Language, but not executive deficits persisted during follow-up. Voxel-based lesion-symptom mapping revealed an association of verbal memory deficits with anterior thalamus lesions and an association of non-verbal memory, language, and executive deficits with lesions at the anterior/paramedian/inferolateral border. CONCLUSIONS All 3 stroke topographies exhibited significant deficits in diverse cognitive domains, which recovered to a different degree depending on the stroke localization. Our study emphasizes the need for comprehensive neuropsychological diagnostics to secure adequate patient rehabilitation