Post natal use of analgesics: comparisons between conventional postnatal wards and a maternity hotel

Aim To investigate factors related to analgesic use after delivery, and especially whether rates of analgesic use were different in a midwife-managed maternity hotel as compared to conventional postnatal wards. Setting One maternity hotel and two conventional postnatal wards at Ullev?l University Hospital in Oslo, Norway. Method Data were obtained from hospital records for 804 women with vaginal deliveries. Main outcome measure Postnatal analgesic use. Results Overall, approximately half the women used analgesics after vaginal delivery in both conventional postnatal wards and maternity hotel. The factors that were significantly associated with use of analgesics postnatally in multivariate analysis were multiparity, having a non-Western ethnicity, smoking in pregnancy, younger age, instrumental delivery, analgesic use during labour, maternal complications post partum, and duration of postnatal stay 4 days or more. Conclusion The use of analgesics is determined by socio-demographic and obstetric factors rather than the organisation of the ward.     

The expanding landscape of diffusion-weighted MRI in prostate cancer

The added value of diffusion-weighted magnetic resonance imaging (DW-MRI) for the detection, localization, and staging of primary prostate cancer has been extensively reported in original studies and meta-analyses. More recently, DW-MRI and related techniques have been used to noninvasively assess prostate cancer aggressiveness and estimate its biological behavior. The present article aims to summarize the potential applications of DW-MRI for noninvasive optimization of pretherapeutic risk assessment, patient management decisions, and evaluation of treatment response.     

l-kynurenine combined with probenecid and the novel synthetic kynurenic acid derivative attenuate nitroglycerin-induced nNOS in the rat caudal trigeminal nucleus

Systemic administration of the nitric oxide (NO) donor nitroglycerin (NTG) triggers a delayed attack without aura in many migraineurs, but not in healthy volunteers. In rats, 4 h after the systemic administration of NTG (10 mg/kg bw, s.c.), the neurons of the caudal trigeminal nucleus (TNC) are activated and the expression of neuronal NO synthase (nNOS) in the same area is increased suggesting a self-amplifying process in the trigeminal system, which seems to be crucial in migraine pathogenesis. Kynurenic acid (KYNA) and its analogues may exert modulatory effects in many neuropathological conditions, probably via N-methyl-d-aspartate (NMDA) antagonism. Since NMDA receptors play a crucial role in trigeminal pain processing, the aim of our experiments was to compare the effects of l-kynurenine (l-KYN) combined with probenecid (PROB) or with 2-(2-N,N-dimethylaminoethylamine-1-carbonyl)-1H-quinolin-4-one hydrochloride alone, a newly synthetized KYNA derivative, on the NTG-induced nNOS expression in the rat TNC. Pretreatment with l-KYN (300 mg/kg bw, i.p.) together with PROB (200 mg/kg bw, i.p.) and KYNA derivative (300 mg/kg bw, i.p.) attenuated the NTG-induced nNOS expression in the rat TNC. Our data suggest that the stimulating effect of NTG, and thus of NO, on the expression of nNOS might be modulated by increasing the KYNA level in the brain, probably through the NMDA receptors. These data could help promote a better understanding of the pathogenesis of headaches and the action of antimigraine drugs.     

Combined endorectal and phased-array MRI in the prediction of pelvic lymph node metastasis in prostate cancer

OBJECTIVE: The objectives of our study were to evaluate the accuracy of combined endorectal and phased-array MRI in detecting pelvic lymph node metastasis (LNM) in patients with prostate cancer and to determine whether radiologists' predictions of LNM improve with the incorporation of Partin nomogram or MRI findings (or both) regarding extracapsular extension or seminal vesicle invasion. SUBJECTS AND METHODS: Between May 1999 and September 2003, 411 consecutive patients with clinically localized prostate cancer underwent MRI before surgery. Serum prostate-specific antigen (PSA) level, Gleason grade, clinical stage, greatest percentage of cancer and percentage of positive cores in all biopsy cores, presence of perineural invasion on biopsy, and likelihood of LNM based on the Partin tables (2001 version) were recorded. MRI studies were interpreted prospectively, but the risks of LNM, extracapsular extension, and seminal vesicle invasion were scored retrospectively on the basis of the MRI reports. Surgical pathology constituted the standard of reference. The accuracy of LNM prediction was assessed using areas under receiver operating characteristic curves (AUCs) and univariate and multivariate logistic regression analyses. For multivariate models, the jackknife method was used for bias correction. A p value below 0.05 denoted statistical significance. RESULTS: At surgical pathology, LNM was present in 22 (5%) of 411 patients. MRI was an independent statistically significant predictor of LNM (p = 0.002), with positive and negative predictive values of 50% and 96.36%, respectively. On multivariate analysis, prediction of lymph node status using the model that included all MRI variables (extracapsular extension, seminal vesicle invasion, and LNM) along with the Partin nomogram results had a significantly greater AUC than the univariate model that included only MRI LNM findings (AUC = 0.892 vs 0.633, respectively; p < 0.01). CONCLUSION: Incorporation of the Partin nomogram results and MRI findings regarding both extracapsular extension and seminal vesicle invasion improves the MR prediction of LNM in patients with prostate cancer.     

Retained seminal vesicles after radical prostatectomy: frequency, MRI characteristics, and clinical relevance

OBJECTIVE: Changes after radical prostatectomy (RP) may present potential pitfalls in the interpretation of pelvic MRI studies in post-RP patients. One such change is retained seminal vesicles (SVs). The purpose of this study was to characterize the MRI features and evaluate the frequency of retained SV remnants in patients after RP. CONCLUSION: Retained SV remnants are a common finding after RP. Most are fibrotic distal tips. Recognition of SV remnants may prevent their misinterpretation as local recurrences.     

MR imaging of renal cortical tumours: qualitative and quantitative chemical shift imaging parameters

Objectives

To assess qualitative and quantitative chemical shift MRI parameters of renal cortical tumours.

Methods

A total of 251 consecutive patients underwent 1.5-T MRI before nephrectomy. Two readers (R1, R2) independently evaluated all tumours visually for a decrease in signal intensity (SI) on opposed- compared with in-phase chemical shift images. In addition, SI was measured on in- and opposed-phase images (SI^IP, SI^OP) and the chemical shift index was calculated as a measure of percentage SI change. Histopathology served as the standard of reference.

Results

A visual decrease in SI was identified significantly more often in clear cell renal cell carcinoma (RCCs) (R1, 73 %; R2, 64 %) and angiomyolipomas (both, 80 %) than in oncocytomas (29 %, 12 %), papillary (29 %, 17 %) and chromophobe RCCs (13 %, 9 %; all, P?<?0.05). Median chemical shift index was significantly greater in clear cell RCC and angiomyolipoma than in the other histological subtypes (both, P?<?0.001). Interobserver agreement was fair for visual (kappa, 0.4) and excellent for quantitative analysis (concordance correlation coefficient, 0.80).

Conclusions

A decrease in SI on opposed-phase chemical shift images is not an identifying feature of clear cell RCCs or angiomyolipomas, but can also be observed in oncocytomas, papillary and chromophobe RCCs. After excluding angiomyolipomas, a decrease in SI of more than 25 % was diagnostic for clear cell RCCs.

Key Points

? Chemical shift MRI offers new information about fat within renal tumours. ? Opposed-phase signal decrease can be observed in all renal cortical tumours. ? A greater than 25 % decrease in signal appears to be diagnostic for clear cell RCCs     

Tumor hypoxia imaging in orthotopic liver tumors and peritoneal metastasis: a comparative study featuring dynamic <Superscript>18</Superscript>F-MISO and <Superscript>124</Superscript>I-IAZG PET in the same study cohort

Purpose The purpose of this paper is to compare the uptake of two clinically promising positron emission tomography (PET) hypoxia targeting agents, ¹²⁴I-iodoazomycin galactopyranoside (¹²⁴I-IAZG) and ¹⁸F-fluoromisonidazole (¹⁸F-FMISO), by dynamic microPET imaging, in the same rats bearing liver tumors and peritoneal metastasis. Methods Morris hepatoma (RH7777) fragments were surgically implanted into the livers of four nude rats. Tumors formed in the liver and disseminated into the peritoneal cavity. Each rat had a total of two to three liver tumors and peritoneal metastasis measuring 10–15 mm in size. Animals were injected with ¹⁸F-FMISO, followed on the next day (upon complete ¹⁸F decay) by ¹²⁴I-IAZG. The animals were imaged in list mode on the microPET system from the time of injection of each tracer for 3 h and then again at 6 h and 24 h for the long-lived ¹²⁴I-IAZG tracer (4.2-day half-life). Micro computed tomography (CT) scans of each rat were performed for co-registration with the microPET scans acquired with a liver contrast agent, allowing tumor identification. Regions of interest (ROIs) were drawn over the heart, liver, muscle, and the hottest areas of the tumors. Time–activity curves (TACs) were drawn for each tissue ROI. Results The ¹⁸F-FMISO signal increased in tumors over the 3-h time course of observation. In contrast, after the initial injection, the ¹²⁴I-IAZG signal slowly and continuously declined in the tumors. Nevertheless, the tumor-to-normal-tissue ratios of ¹²⁴I-IAZG increased, but more slowly than those of ¹⁸F-FMISO and as a result of the differentially faster clearance from the surrounding normal tissues. These pharmacokinetic patterns were seen in all 11 tumors of the four animals. Conclusions ¹⁸F-FMISO localizes in the same intra-tumor regions as ¹²⁴I-IAZG. The contrast ratios (tumor/background) reach similar values for the two hypoxia tracers, but at later times for ¹²⁴I-IAZG than for ¹⁸F-FMISO and, therefore, with poorer count statistics. As a consequence, the ¹⁸F-FMISO images are of superior diagnostic image quality to the ¹²⁴I-IAZG images in the Morris hepatoma McA-R-7777 tumor model. Supported in part by R25-CA096945-3 (C.C.R., P.B., H.H., J.L.H.) and by NCI grant PO1 CA115675 on the Detection of Tumor Hypoxia by Non Invasive Nuclear Imaging Methods (C.C.L and J.L.H).