Pelvic lymph node dissection in prostate cancer

CONTEXT: Pelvic lymph node dissection (PLND) is considered the most reliable procedure for the detection of lymph node metastases in prostate cancer (PCa); however, the therapeutic benefit of PLND in PCa management is currently under debate. OBJECTIVE: To systematically review the available literature concerning the role of PLND and its extent in PCa staging and outcome. All of the existing recommendations and staging tools determining the need for PLND were also assessed. Moreover, a systematic review was performed of the long-term outcome of node-positive patients stratified according to the extent of nodal invasion. EVIDENCE ACQUISITION: A Medline search was conducted to identify original and review articles as well as editorials addressing the significance of PLND in PCa. Keywords included prostate cancer, pelvic lymph node dissection, radical prostatectomy, imaging, and complications. Data from the selected studies focussing on the role of PLND in PCa staging and outcome were reviewed and discussed by all of the contributing authors. EVIDENCE SYNTHESIS: Despite recent advances in imaging techniques, PLND remains the most accurate staging procedure for the detection of lymph node invasion (LNI) in PCa. The rate of LNI increases with the extent of PLND. Extended PLND (ePLND; ie, removal of obturator, external iliac, hypogastric with or without presacral and common iliac nodes) significantly improves the detection of lymph node metastases compared with limited PLND (lPLND; ie, removal of obturator with or without external iliac nodes), which is associated with poor staging accuracy. Because not all patients with PCa are at the same risk of harbouring nodal metastases, several nomograms and tables have been developed and validated to identify candidates for PLND. These tools, however, are based mostly on findings derived from lPLND dissections performed in older patient series. According to these prediction models, a staging PLND might be omitted in low-risk PCa patients because of the low rate of lymph node metastases found, even after extended dissections (<8%). The outcome for patients with positive nodes is not necessarily poor. Indeed, patients with low-volume nodal metastases experience excellent survival rates, regardless of adjuvant treatment. But despite few retrospective studies reporting an association between PLND and PCa progression and survival, the exact impact of PLND on patient outcomes has not yet been clearly proven because of the lack of prospective randomised trials. CONCLUSIONS: On the basis of current data, we suggest that if a PLND is indicated, then it should be extended. Conversely, in view of the low rate of LNI among patients with low-risk PCa, a staging ePLND might be spared in this patient category. Whether this approach is also safe from oncologic perspectives is still unknown. Patients with low-volume nodal metastases have a good long-term prognosis; to what extent this prognosis is the result of a positive impact of PLND on PCa outcomes is still to be determined.

Expression and function of 5-HT7 receptors in smooth muscle preparations from equine duodenum, ileum, and pelvic flexure

In horses, gastrointestinal (GI) disorders occur frequently and cause a considerable demand for efficient medication. 5-Hydroxytryptamine receptors (5-HT) have been reported to be involved in GI tract motility and thus, are potential targets for treating functional bowel disorders. Our studies extend current knowledge on the 5-HT(7) receptor in equine duodenum, ileum and pelvic flexure by studying its expression throughout the intestine and its role in modulating contractility in vitro by immunofluorescence and organ bath experiments, respectively. 5-HT(7) immunoreactivity was demonstrated in both smooth muscle layers, particularly in the circular one, and within the myenteric plexus. Interstitial cells of Cajal (ICC), identified by c-Kit labeling, show a staining pattern similar to that of 5-HT(7) immunoreactivity. The selective 5-HT(7) receptor antagonist SB-269970 increased the amplitude of contractions in spontaneous contracting specimens of the ileum and in electrical field-stimulated specimens of the pelvic flexure concentration-dependently. Our in vitro experiments suggest an involvement of the 5-HT(7) receptor subtype in contractility of equine intestine. While the 5-HT(7) receptor has been established to be constitutively active and inhibits smooth muscle contractility, our experiments demonstrate an increase in contractility by the 5-HT(7) receptor ligand SB-269970, suggesting it exerting inverse agonist properties.

Subsecond changes of global brain state in illusory multistable motion perception

This study explored transient changes in EEG microstates and spatial Omega complexity associated with changes in multistable perception. 21-channel EEG was recorded from 13 healthy subjects viewing an alternating dot pattern that induced illusory motion with ambiguous direction. Baseline epochs with stable motion direction were compared to epochs immediately preceding stimuli that were perceived with changed motion direction ('reference stimuli'). About 750 ms before reference stimuli, Omega complexity decreased as compared to baseline, and two of four classes of EEG microstates changed their probability of occurrence. About 300 ms before reference stimuli, Omega complexity increased and the previous deviations of EEG microstates were reversed. Given earlier results on Omega complexity and microstates, these sub-second EEG changes might parallel longer-lasting fluctuations in vigilance. Assumedly, the discontinuities of illusory motion thus occur during sub-second dips in arousal, and the following reconstruction of the illusion coincides with a state of relative over-arousal.

Valgus Hip With High Antetorsion Causes Pain Through Posterior Extraarticular FAI

BACKGROUND: Valgus hips with increased antetorsion present with lack of external rotation and posterior hip pain that is aggravated with hip extension and external rotation. This may be the result of posterior femoroacetabular impingement (FAI). QUESTIONS/PURPOSES: We asked whether (1) the range of motion (ROM); (2) the location of anterior and posterior bony collision zones; and (3) the prevalence of extraarticular impingement differ between valgus hips with increased antetorsion compared with normal hips and hips with idiopathic FAI. METHODS: Surface models based on CT scan reconstructions of 13 valgus hips with increased antetorsion, 22 hips with FAI, and 27 normal hips were included. Validated three-dimensional collision detection software was used to quantify the simulated hip ROM and the location of impingement on the acetabular and the femoral sides. RESULTS: Hips with coxa valga and antetorsion showed decreased extension, external rotation, and adduction, whereas internal rotation in 90° of flexion was increased. Impingement zones were more anteroinferior on the femur and posteroinferior on the acetabular (pelvic) side; and the zones were more frequently extraarticular, posterior, or to a lesser degree anterior against the inferior iliac spine. We found a higher prevalence of extraarticular impingement for valgus hips with increased antetorsion. CONCLUSIONS: Valgus hips with increased antetorsion predispose to posterior extraarticular FAI and to a lesser degree anteroinferior spine impingement. LEVEL OF EVIDENCE: Level II, prognostic study. See Guidelines for Authors for a complete description of levels of evidence.

Direction detection thresholds of passive self-motion in artistic gymnasts

In this study, we compared direction detection thresholds of passive self-motion in the dark between artistic gymnasts and controls. Twenty-four professional female artistic gymnasts (ranging from 7 to 20 years) and age-matched controls were seated on a motion platform and asked to discriminate the direction of angular (yaw, pitch, roll) and linear (leftward–rightward) motion. Gymnasts showed lower thresholds for the linear leftward–rightward motion. Interestingly, there was no difference for the angular motions. These results show that the outstanding self-motion abilities in artistic gymnasts are not related to an overall higher sensitivity in self-motion perception. With respect to vestibular processing, our results suggest that gymnastic expertise is exclusively linked to superior interpretation of otolith signals when no change in canal signals is present. In addition, thresholds were overall lower for the older (14–20 years) than for the younger (7–13 years) participants, indicating the maturation of vestibular sensitivity from childhood to adolescence.

The von Mises-Fisher distribution of the first exit point from the hypersphere of the drifted Brownian motion and the density of the first exit time

A characterization is provided for the von Mises–Fisher random variable, in terms of first exit point from the unit hypersphere of the drifted Wiener process. Laplace transform formulae for the first exit time from the unit hypersphere of the drifted Wiener process are provided. Post representations in terms of Bell polynomials are provided for the densities of the first exit times from the circle and from the sphere.