Dosimetric and toxicity comparison between Syed-Neblett and Fletcher-Suit-Delclos Tandem and Ovoid applicators in high dose rate cervix cancer brachytherapy.

PURPOSE: To compare patient and tumor characteristics, dosimetry, and toxicities between interstitial Syed-Neblett and intracavitary Fletcher-Suit-Delclos Tandem and Ovoid (T&O) applicators in high dose rate (HDR) cervical cancer brachytherapy. METHODS: A retrospective analysis was performed for cervical cancer patients treated with 3D-based HDR brachytherapy from 2011 to 2023 at a single institution. Dosimetric parameters for high-risk clinical target volume and organs at risk were obtained. Toxicities were evaluated using the Common Terminology Criteria for Adverse Events version 5.0. RESULTS: A total of 115 and 58 patients underwent Syed and T&O brachytherapy, respectively. Patients treated with Syed brachytherapy were more likely to have larger tumors and FIGO stage III or IV disease. The median D2cc values to the bladder, small bowel, and sigmoid colon were significantly lower for Syed brachytherapy. Patients treated with Syed brachytherapy were significantly more likely to be free of acute gastrointestinal (44% vs. 21%, p = 0.003), genitourinary (58% vs. 36%, p = 0.01), and vaginal toxicities (60% vs. 33%, p = 0.001) within 6 months following treatment compared to patients treated with T&O applicators. In contrast, Syed brachytherapy patients were more likely to experience late gastrointestinal (68% vs. 49%, p = 0.082), genitourinary (51% vs. 35%, p = 0.196), and vaginal toxicities (70% vs. 57%, p = 0.264). CONCLUSIONS: Syed-Neblett and T&O applicators are suitable for HDR brachytherapy for cervical cancer in distinct patient populations. Acute toxicities are more prevalent with T&O applicators, while patients treated with Syed-Neblett applicators are more likely to develop late toxicities.

Chemoradiation to the submental muscles alters hyoid movement during swallowing in a rat model.

Hyolaryngeal dysfunction is a commonly reported swallowing problem after chemoradiation treatment for head and neck cancer. The displacement of the hyolaryngeal complex during swallowing protects the airway and assists in opening the upper esophageal sphincter. Activation of the submental muscles, specifically the mylohyoid and geniohyoid muscles, is thought to facilitate movement of the hyoid. The purpose of this study was to determine if targeted radiation to the submental muscles given concurrently with chemotherapy alters hyolaryngeal displacement 1 mo after treatment. We hypothesized that chemoradiation treatment would result in abnormal patterns of hyoid movement compared with controls. Furthermore, we propose that these changes are associated with alterations in bolus size and discoordination of the jaw during drinking. Eighteen rats underwent either chemoradiation, radiation, or no treatment. Radiation treatment was targeted to submental muscles using a clinical linear accelerator given in 12 fractions of 4 Gy (3 days per week). Cycles of 1 mg/kg of cisplatin were administered concurrently each week of radiation. One month posttreatment, videofluoroscopy swallow studies (VFSS) were performed in self-drinking rats using a fluoroscope customized with a high-speed camera. The hyoid, jaw, and hard palate were tracked during swallowing from VFSS. Hyoid kinematics were analyzed from the start to the end of hyoid movement, and parameters were compared with bolus size and jaw movement. Significant differences in hyoid retraction parameters were found postchemoradiation. Alterations in the trajectory of hyoid motion during swallowing were observed. The findings demonstrate early changes in hyoid motion during swallowing associated with chemoradiation treatment.NEW & NOTEWORTHY Chemoradiation treatment for head and neck cancer can cause functional impairments in swallowing, which can adversely affect quality of life. This study provides new evidence that chemoradiation targeted to the submental muscles provokes early adaptations in hyoid movement during swallowing, which correlate with changes in bolus size. We also demonstrate a method for tracking the hyoid during swallowing in a rat model of chemoradiation injury.

Multimorbidity analysis and hospitalizations for diabetes before and after lockdown due to the COVID-19 pandemic in Peru.

COVID-19 has disrupted the treatment of non-communicable diseases (NCDs). This study conducted a multimorbidity analysis and evaluated hospital admissions and death rates among diabetic patients before and after the implementation of lockdown due to the COVID-19 pandemic in Peru. Data from the Ministry of Health (MINSA) of Peru from January 2017 to December 2020 was used. Hospital death, discharge and the percentage of death/hospital admissions were defined as outcomes of interest. We performed an interrupted time series analysis to assess the aggregate change in the outcomes of interest before and after mandatory lockdown in response to the COVID-19 pandemic in Peru (n = 65,935). Additionally, a network analysis was performed to evaluate the frequency of occurrence of hospital admissions before and after the mandatory lockdown according to demographic characteristics. The average monthly hospital admissions among diabetic patients in Peru decreased by 29% after the implementation of the lockdown. The largest reduction was observed in women (-41%) and for patients 60 years or older (-35%). Furthermore, there was a 92% increase in the average number of monthly deaths. The largest percentage change occurred in men (+113%) and in the group of 40-59 years (+144%). After the implementation of lockdown in Peru, hospital admissions among diabetic patients significantly decreased while in-hospital mortality slightly increased. Our findings shed light on the limitations of the Peruvian health system and the importance of ensuring continued care of NCDs as part of the response strategy during times of crisis.

Determinants of Eye Care Service Utilization among Peruvian Adults: Evidence from a Nationwide Household Survey.

PURPOSE: This study analyzes the factors associated with eye care service utilization among Peruvians 50 years of age and older, measured as self-reporting of having undergone examination of visual acuity during the last 12 months. METHODS: A secondary analysis of the 2019 Demographic and Family Health Survey (ENDES, for its acronym in Spanish) database was carried out. We estimated the weighted proportion of adults 50 years of age and older that reported having undergone a visual acuity examination in the previous 12 months and the frequency according to the variables of interest. Crude (PR) and adjusted prevalence ratios (aPR) of eye care service utilization were constructed using generalized linear models. RESULTS: Approximately 28.8% of Peruvians 50 years of age and older underwent a visual acuity examination in the previous 12 months. Having a higher education (aPR = 1.79; 95% CI: 1.33-2.40), health insurance such as EsSalud (aPR = 1.54; 95% CI: 1.28-1.87), a previous diagnosis of cataracts (aPR = 1.86; 95% CI: 1.67-2.09) and being part of the richest wealth quintile (aPR = 2.36; 95% CI: 1.74-3.20) were associated with greater utilization of eye care services, while living in the jungle was associated with a lower likelihood of utilization of these services. CONCLUSION: The unequal distribution of health resources within the territory and socioeconomic gaps among the population could explain our findings. Further efforts are needed to fulfill the eye health needs of the Peruvian population.

Diagnostic Reference Levels for Common X-ray Procedures in Peru.

Diagnostic reference levels (DRLs) for X-ray procedures have been established in many countries since 1996. In Peru, data from the literature are used as guidelines as DRLs research is limited. The objective of this study is to analyze the parameters and variables which are used in radiological techniques such as kV, mAs, and type of machine (conventional or digital); study the geographical distribution of radiological X-ray machines, and establish DRLs in Peru. Two radiological procedures were considered, general X-rays (fixed and mobile) and intraoral X-rays (fixed, mobile, and portable). An Unfors RaySafe Xi detector (Unfors RaySafe AB, Billdal, Sweden) was used; air kerma was measured at a source to image distance that varied depending on the procedure, and the entrance skin dose was subsequently calculated using the Arcal XLIX formalism. The data were collected over a period of three years (2015-2017). Only results from the last evaluation during this period were taken into consideration for each X-ray machine. DRLs were calculated at 0.21 mSv, and 0.25 mSv for posterior-anterior chest examinations in conventional and digital machines, respectively; 4.39 mSv and 6.01 mSv for conventional and digital antero-posterior lumbar spine examinations, respectively; and at 4.21 mSv for the dental intraoral procedure. The largest amount of X-ray machines is concentrated in the city of Lima. These results reflect the standard of practice in Peru.

Simple and low cost alternative method for detecting photoneutrons produced in some radiotherapy treatments using SSNTDs.

A simple and low cost alternative which is able to identify thermal and fast neutrons in a clinical environment of radiotherapy is presented. CR-39 and LR-115 Solid State Nuclear Track Detectors (SSNTDs) were used, estimating their viability. In order to register alpha tracks due to thermal neutrons, natural boric acid tablets were placed in close contact to the detector, whereas in order to detect epithermal neutrons, some were additionally covered in a thin cadmium layer. Different configurations were assembled, changing the position of the converter with respect to the detector and the incident neutron fluence, which was evaluated in different positions of a radiotherapy table. The contribution due to environmental 222Rn and its daughters to the track density registered by the detector during the measurements was found to be negligible. It is concluded that the designed experimental set up constitutes a trustworthy and affordable method to carry out neutron measurements with the recommended configurations provided for the CR-39 detector, and not with LR-115.

Comparación de aspectos de seguridad radiológica en odontopediatras con profesionales de distintas especialidades odontológicas de Lima ­ Perú

Objetivo: En los últimos años se viene realizando una labor de control y certificación de calidad en los temas relacionados a la radiación ionizante para obtener diversos objetivos; entre ellos, optimizar tratamientos, promover la salud ocupacional, etc. La presente investigación analiza el cumplimiento -por parte de profesionales en odontología- del uso de un protocolo de seguridad radiológica, creado a partir de leyes peruanas y recomendaciones internacionales. Metodología: Se elaboró una escala denominada "Protocolo de Seguridad Radiológica", integrada por 15 afirmaciones, cada uno con tres posibles respuestas y un puntaje, cuya suma representa el índice de cumplimiento de las normas de protección radiológica. Las afirmaciones y el protocolo en su conjunto pasaron por un análisis estadístico, con la finalidad de establecer la validez de confiabilidad de los mismos. La población de estudio abarcó profesionales de odontología de las especialidades de Endodoncia, Periodoncia, Odontopediatría; Rehabilitación Oral, Estética y Ortodoncia, de la Universidad Científica del Sur de Lima-Perú. De ella se seleccionó una muestra no probabilística de tipo intencional, integrada por 108 personas (34 hombres y 74 mujeres). Resultados: Se halló que los endodoncistas (puntaje promedio en la escala: 15.89, que representa el 52.97% del puntaje total de la misma) y odontopediatras (promedio 16.68, que representa el 55.6% del puntaje total) son los profesionales de las especialidades que menos se rigen en el "Protocolo de Seguridad Radiológica". Conclusiones: Se determinó que las prácticas o comportamientos de los diversos especialistas odontólogos, relacionados al cumplimiento del uso del "Protocolo de Seguridad Radiológica", no garantizan calidad en relación al mismo.