Pinhole imaging of <Superscript>131</Superscript>I-metaiodobenzylguanidine (<Superscript>131</Superscript>I-MIBG) in an animal model of neuroblastoma

Purpose To evaluate ¹³¹I-MIBG scintigraphic localization of xenotransplanted and spontaneously arising neuroblastomas in murine models of high-risk neuroblastoma.Methods Neuroblastoma xenografts were created by inoculation of human neuroblastoma cell suspensions into the subcutaneous flanks of athymic nude mice. In addition, spontaneous paraspinal neuroblastomas were detected by direct palpation in MYCN transgenic mice. After measured tumor volumes exceeded 200 mm³, each mouse received an intraperitoneal injection of 18 Ci/g ¹³¹I-metaiodobenzylguanidine (¹³¹I-MIBG). Pinhole scintigraphy was performed to evaluate the MIBG biodistribution and to attempt to visualize the tumors. Each mouse was imaged on a gamma camera equipped with a 3-mm pinhole on one head and an HEGP collimator on the other.Results Images demonstrated absorption of radiolabeled MIBG and visualization of tumors. Analysis of the images allowed for quantification of relative MIBG uptake and for determination of linear and area measurements of the tumors.Conclusion High-energy pinhole imaging effectively demonstrates uptake of radiolabeled MIBG by human neuroblastoma tumors in murine laboratory models. This technique allows for in vivo assessment of tumor burden. In the future, we plan to use this method to evaluate sensitivity for detecting metastatic spread as well as investigating the therapeutic efficacy of high-dose ¹³¹I-MIBG in combination with radiosensitizing agents.     

Femtosecond laser deep lamellar keratoplasty

We aimed to develop a novel and effective technique for creating a smooth deep lamellar dissection of the cornea using a femtosecond (FS) laser for deep anterior lamellar keratoplasty (DALK), we conducted a retrospective eye bank study. Thirteen fresh human corneas were mounted on an artificial anterior chamber, and deep lamellar cuts were made with a 500-kHz VisuMax FS laser at a level of 50–80 mm anterior to the Descemet’s membrane (DM). A posterior diameter of 8 mm with a side cut angle of 110° was used for the anterior penetrating side cut. The anterior lamellar tissue was bluntly dissected. The residual posterior stromal beds and side cuts were examined with microscopy and intraoperative optical coherence tomography (OCT) and post-cut endothelial cell evaluations. All corneas revealed a smooth residual posterior stromal bed without any visible irregularities or ridges by microscopy and OCT imaging. Six corneas were suitable for post-cut endothelial cell evaluation 2 days after laser cut, with no significant endothelial cell loss post-laser and blunt dissection of the posterior stroma. FS laser deep lamellar keratoplasty utilizing an ultrafast laser to produce a smooth deep stromal dissection followed by blunt dissection and removal of the anterior stromal tissue yields a consistent and smooth residual stromal bed. The creation of a smooth lamellar dissection in the deep posterior cornea may result in more consistent DALK without the need for air bubble or manual baring of DM that has the risk for DM perforation.     

A scoring system for AML patients aged 70 years or older,eligible for intensive chemotherapy: a study based on a large European data set using the DATAML,SAL, and PETHEMA registries

In a context of therapeutic revolution in older adults with AML, it is becoming increasingly important to select patients for the various treatment options by taking account of short-term efficacy and toxicity as well as long-term survival. Here, the data from three European registries for 1,199 AML patients aged 70 years or older treated with intensive chemotherapy were used to develop a prognostic scoring system. The median follow-up was 50.8 months. In the training set of 636 patients, age, performance status, secondary AML, leukocytosis, and cytogenetics, as well as NPM1 mutations (without FLT3-ITD), were all significantly associated with overall survival, albeit not to the same degree. These factors were used to develop a score that predicts long-term overall survival. Three risk-groups were identified: a lower, intermediate and higher-risk score with predicted 5-year overall survival (OS) probabilities of ≥12% (n = 283, 51%; median OS = 18 months), 3–12% (n = 226, 41%; median OS = 9 months) and <3% (n = 47, 8%; median OS = 3 months), respectively. This scoring system was also significantly associated with complete remission, early death and relapse-free survival; performed similarly in the external validation cohort (n = 563) and showed a lower false-positive rate than previously published scores. The European Scoring System ≥70, easy for routine calculation, predicts long-term survival in older AML patients considered for intensive chemotherapy.Subject terms: Acute myeloid leukaemia, Risk factors     

Improving Physician Knowledge: A Necessary but Not Sufficient Requirement of Improving Intrauterine Contraception Access in Canada

ObjectiveThis study sought to identify knowledge gaps and attitudinal barriers to prescribing intrauterine contraception (IUC).MethodsA national, Web-based survey of Canadian gynaecology (GYN) and family medicine (FM) physicians was conducted. The survey was distributed through several channels, including physicians’ databases, invitations through a commercial email aggregating service, and contacting residency programs. For knowledge-based questions, correct answers were those consistent with Canadian practice guidelines. Ethics approval was granted through Queen's Health Sciences Research Ethics Board. Project funding was through a research grant from Bayer, Inc. (Canadian Task Force Classification III).ResultsA total of 600 responses were received. GYN physicians’ knowledge about IUC (number correct / 40) was better than that of the FM and FM with additional women's health training (FMWH) groups (median [interquartile range] 39 [37–40], 36 [32–38], and 37 [35–39]; P < 0.0001). Factors associated with lower scores included rural practice location, lack of affiliation with medical trainees, extremes of practice duration, and self-perceived lack of knowledge about IUC. Most respondents prescribed IUC (93.7%). Among prescribers, 97.0% inserted IUC. The most common reasons for not prescribing or inserting IUC included lack of training, lack of comfort, and referral to other physicians to provide this service. Respondents indicated that they would be more likely to prescribe and/or insert IUC if cost barriers were removed, patient interest was increased, or if there was improved access to patient-centred educational materials and hands-on training modules.ConclusionThis study suggests that although many GYN and FM physicians are offering IUC, misconceptions regarding contraindications still exist, and several barriers are related to deficiencies in providers’ knowledge. Therefore, educational efforts should be prioritized to increase the usage of IUC.