Magnetic Resonance Image-Guided Radiotherapy (MRIgRT): A 4.5-Year Clinical Experience.

AIMS: Magnetic resonance image-guided radiotherapy (MRIgRT) has been clinically implemented since 2014. This technology offers improved soft-tissue visualisation, daily imaging, and intra-fraction real-time imaging without added radiation exposure, and the opportunity for adaptive radiotherapy (ART) to adjust for anatomical changes. Here we share the longest single-institution experience with MRIgRT, focusing on trends and changes in use over the past 4.5 years. MATERIALS AND METHODS: We analysed clinical information, including patient demographics, treatment dates, disease sites, dose/fractionation, and clinical trial enrolment for all patients treated at our institution using MRIgRT on a commercially available, integrated 0.35 T MRI, tri-cobalt-60 device from 2014 to 2018. For each patient, factors including disease site, clinical rationale for MRIgRT use, use of ART, and proportion of fractions adapted were summated and compared between individual years of use (2014-2018) to identify shifts in institutional practice patterns. RESULTS: Six hundred and forty-two patients were treated with 666 unique treatment courses using MRIgRT at our institution between 2014 and 2018. Breast cancer was the most common disease, with use of cine MRI gating being a particularly important indication, followed by abdominal sites, where the need for cine gating and use of ART drove MRIgRT use. One hundred and ninety patients were treated using ART in 1550 fractions, 67.6% (1050) of which were adapted. ART was primarily used in cancers of the abdomen. Over time, breast and gastrointestinal cancers became increasingly dominant for MRIgRT use, hypofractionated treatment courses became more popular, and gastrointestinal cancers became the principal focus of ART. DISCUSSION: MRIgRT is widely applicable within the field of radiation oncology and new clinical uses continue to emerge. At our institution to date, applications such as ART for gastrointestinal cancers and accelerated partial breast irradiation (APBI) for breast cancer have become dominant indications, although this is likely to continue to evolve.

Quality of life impact of childhood skin conditions measured using the Children's Dermatology Life Quality Index (CDLQI): a meta-analysis.

BACKGROUND: The Children's Dermatology Life Quality Index (CDLQI) is the most widely used instrument for measuring the impact of skin disease on quality of life (QoL) in children. OBJECTIVES: To provide a meta-analysis of all published QoL scores for a range of childhood skin conditions. METHODS: Studies using the CDLQI questionnaire to measure QoL in skin conditions were identified by searching Medline and Embase from January 1995 (CDLQI creation) to December 2014. Studies were grouped according to condition and baseline scores were combined using meta-analysis. RESULTS: Sixty-seven studies using the CDLQI met the inclusion criteria. The overall estimated CDLQI scores for conditions reported more than once were [point estimate (95% confidence interval, CI), number of studies (n), score range]: atopic eczema [8·5 (7·1-9·8), n = 38, 0-29], acne [5·3 (1·9-8·5), n = 5, 0-30], alopecia [3·1 (0-7·7), n = 2, 0-6], molluscum contagiosum [3·5 (0·6-6·7), n = 5, 0-27], psoriasis [8·0 (3·9-12·1), n = 6, 0-29], scabies [9·2 (0·0-20·3), n = 2, 1-26], urticaria [7·1 (0-15·4), n = 2, 0-22], vitiligo [6·5 (0·7-12·2), n = 2, 0-20] and warts [2·9 (0-5·8), n = 4, 0-16]. Overall, the mean effect on QoL [weighted average CDLQI score 4·6 (95% CI 3·9-5·4)] for children with these conditions was small. However, many children were found to experience a very large impact on QoL (34% of children with atopic eczema, 10% with molluscum contagiosum and 1-5% with acne) in studies where the distributions of scores were provided. CONCLUSIONS: Most skin conditions in children have a 'small' mean effect on QoL. However, the range is large and a significant proportion of children with many common skin conditions will experience a very large effect on quality of life.

An automated method for adaptive radiation therapy for prostate cancer patients using continuous fiducial-based tracking.

Electromagnetic tracking technology is primarily used for continuous prostate localization during radiotherapy, but offers potential value for evaluation of dosimetric coverage and adequacy of treatment for dynamic targets. We developed a highly automated method for daily computation of cumulative dosimetric effects of intra- and inter-fraction target motion for prostate cancer patients using fiducial-based electromagnetic tracking. A computer program utilizing real-time tracking data was written to (1) prospectively determine appropriate rotational/translational motion limits for patients treated with continuous isocenter localization; (2) retrospectively analyze dosimetric target coverage after daily treatment, and (3) visualize three-dimensional rotations and translations of the prostate with respect to the planned target volume and dose matrix. We present phantom testing and a patient case to validate and demonstrate the utility of this application. Gamma analysis of planar dose computed by our application demonstrated accuracy within 1%/1 mm. Dose computation of a patient treatment revealed high variation in minimum dose to the prostate (D(min)) over 40 fractions and a drop in the D(min) of approximately 8% between a 5 mm and a 3 mm PTV margin plan. The infrastructure has been created for patient-specific treatment evaluation using continuous tracking data. This application can be used to increase confidence in treatment delivery to targets influenced by motion.

Duration of daily bull exposure on resumption of ovulatory activity in postpartum, primiparous, suckled, beef cows.

The objective of this experiment was to determine if duration of daily bull exposure influences length of postpartum anestrus in primiparous, anovular, suckled, beef cows. The null hypotheses were that intervals from calving or the start of bull exposure (D 0) to resumption of ovulatory activity (OA), and proportions of cows that resumed OA during the experiment does not differ among cows exposed to bulls for 0h, 6h, or 12h daily, and that there is no relationship between the duration of bull exposure and interval to resumption of OA in cows exposed to bulls for 0h, 6h, or 12h daily. At 51.5+/-2.3d (+/-SE) after calving, cows were assigned randomly to be exposed for 12h (BE12; n=15) or 6h daily (BE6; n=14) to bulls, or not exposed to bulls (NE; n=10) for 45 d. Interval from calving or from D 0 to resumption of OA was shorter (P<0.05) and the proportion of cows that resumed OA during the experiment was greater (P<0.05) for BE12 than for NE cows. Interval from D 0 to resumption of OA did not differ (P>0.10) between BE6 cows and either BE12 or NE cows. However, interval from calving to resumption of OA was shorter (P<0.05) for BE6 than NE cows. The proportion of cows that resumed OA did not differ (P>0.10) between BE6 cows and BE12 cows; however, the proportion of cows that resumed OA during the experiment tended (P=0.08) to be greater for BE6 cows than for NE cows. There was a linear relationship between intervals from calving (b(1)=-7.64 d/h; P<0.05) and D 0 (b(1)=-3.3 d/h; P<0.05) to resumption of OA and duration of daily bull exposure. Thus, the duration of bull-pheromone stimuli that cows perceive each day is related to when primiparous, postpartum, anestrous, suckled cows respond to this stimulus and undergo the physiological changes necessary to resume ovulatory activity.

Comparison of controlled internal drug release device and melengesterol acetate as progestin sources in an estrous synchronization protocol for beef heifers.

The objectives of this experiment were to compare estrous synchronization responses and AI pregnancy rates of beef heifers using protocols that included either CIDR or MGA as the progestin source. The hypotheses tested were that: (1) estrous synchronization responses after (a) progestin removal, and (b) PGF(2alpha); and, (2) AI pregnancy rates, do not differ between heifers synchronized with either progestin source. At the start of the experiment (Day 0) in both years, heifers were assigned randomly to receive, MGA supplement for 14 days (MGA-treated; n=79) or CIDR for 14 days (CIDR-treated; n=77). On Day 14 progestin was removed and heifers were observed for estrus up to and after PGF(2alpha) on Days 31 and 33 for CIDR-treated and MGA-treated heifers, respectively. Heifers that exhibited estrus within 60h after PGF(2alpha) were inseminated by AI 12h later; the remaining heifers were inseminated at 72h after PGF(2alpha) and given GnRH (100mug). More (P<0.05) CIDR-treated heifers exhibited estrus within 120h after progestin removal than MGA-treated heifers. Intervals to estrus after progestin removal were shorter (P<0.05) for CIDR-treated heifers than MGA-treated heifers. More (P<0.05) CIDR-treated heifers exhibited estrus and were inseminated within 60h after PGF(2alpha) than MGA-treated heifers. Pregnancy rates did not differ (P>0.10) between MGA-treated (66%) and CIDR-treated (62%) heifers. In conclusion, the use of CIDR as a progestin source in a 14-day progestin, PGF(2alpha), and timed AI and GnRH estrous synchronization protocol was as effective as the use of MGA to synchronize estrus and generate AI pregnancies in beef heifers.

Long-term follow-up of upper extremity implanted venous access devices in oncology patients.

PURPOSE: To evaluate function and assess incidence of complications relating to upper extremity implanted venous access devices placed in oncology patients primarily for chemotherapy. MATERIALS AND METHODS: The authors retrospectively evaluated the clinical course of 205 upper extremity implanted venous access devices placed with fluoroscopic and sonographic guidance in 204 patients during a 2-year period. All patients had a diagnosis of malignancy for which chemotherapy was planned. Follow-up data were collected by patient examination, direct evaluation of device function, as well as chart review and review of relevant imaging procedures. A modified technique for device placement is described. RESULTS: The devices were placed successfully on the initial attempt in all cases. Clinical follow-up was obtained for 195 devices (95.1%) for a total device service period of 33,619 days (mean service interval = 169 days). Seventy-eight devices (40%) had service intervals greater than 180 days. Thirty-seven devices (19% of total devices) led to 39 complications (0.116 event/100 days). No immediate procedural complications were incurred. Eight complications occurred after 180 days of port service. Nineteen devices (9.7% of total devices followed) required removal as a result of complication. Common complications included port malfunction requiring urokinase to clear (n = 10; 0.030 event/100 days), ipsilateral upper extremity deep venous thrombosis (n = 9; 0.027), and local infection (n = 7, 0.021). A comparison of these results relative to other published series of similar devices placed for mixed indications is presented. CONCLUSIONS: Implanted venous access devices are an effective means of long-term venous access in oncology patients. Complication rates in this large series compared favorably to other published radiologic and surgical series. Analysis of complications in a subgroup of extended use implanted venous access devices (greater than 180 days follow-up) showed no statistically significant (P < .05) difference from the larger group of devices.

Improved liquid chromatographic determination of riboflavin in milk and dairy products.

Reported here is a simple liquid chromatographic (LC) method for the determination of riboflavin in milk (liquid, evaporated, and dry), yogurt, and cheese. The method involves passing liquid samples or filtrates of semisolid and solid samples through a C18 cartridge. Retained riboflavin is then eluted with an aliquot of 50% methanol in 0.02M acetate buffer of pH 4. A volume of the eluate is injected into the LC system consisting of a C18 column, a solvent of water-methanol-acetic acid (65 + 35 + 0.1, v/v) with a flow rate of 1 mL/min, and a UV detector set at 270 nm. The method is precise and accurate and compares favorably with the present AOAC method. Moreover, it involves fewer sample preparation steps and has a total analysis time of less than 1 h.