Reproductive and fetal toxicity studies of histamine H3 receptor antagonist DL76 used in mice to prevent maximal electroshock-induced seizure.

Introduction: Brain histamine is considered an endogenous anticonvulsant and histamine H1 receptor. H1R antagonists have, in earlier studies, been found to induce convulsions. Moreover, research during the last two decades has provided more information concerning the anticonvulsant activities of histamine H3R (H3R) antagonists investigated in a variety of animal epilepsy models. Methods: Therefore, the in vivo anticonvulsant effect of the H3R antagonist DL76, with proven high in vitro affinity, in vitro selectivity profile, and high in vivo antagonist potency in mice against maximal electroshock (MES)-induced seizures in mice, was assessed. Valproic acid (VPA) was used as a reference antiepileptic drug (AED). In addition, DL76 was tested for its reproductive and fetal toxicity in the same animal species. Results and discussion: Our observations showed that acute systemic administration (intraperitoneal; i.p.) of DL76 (7.5 mg/kg, 15 mg/kg, 30 mg/kg, and 60 mg/kg, i.p.) provided significant and dose-dependent protection against MES-induced seizures in female and male mice. Moreover, the DL76-provided protective effects were comparable to those offered by the VPA and were reversed when animals were co-administered the CNS-penetrant selective H3R agonist R-(α)-methylhistamine (RAM, 10 mg/kg, i.p.). Furthermore, the administration of single (7.5 mg/kg, 15 mg/kg, 30 mg/kg, or 60 mg/kg, i.p.) or multiple doses (3 × 15 mg/kg, i.p.) of H3R antagonist DL76 on gestation days (GD) 8 or 13 failed to affect the maternal body weight of mice when compared with the control mice group. No significant alterations were detected in the average number of implantations and resorptions between the control and DL76-treated groups at the early stages of gestation and the organogenesis period. In addition, no significant differences in the occurrence of skeletal abnormalities, urogenital abnormalities, exencephaly, exomphalos, facial clefts, and caudal malformations were observed. The only significant abnormalities witnessed in the treated groups of mice were in the length of long bones and body length. In conclusion, the novel H3R antagonist DL76 protected test animals against MES-induced seizures and had a low incidence of reproductive and fetal malformation with decreased long bone lengths in vivo, signifying the potential therapeutic value of H3R antagonist DL76 for future preclinical as well as clinical development for use in the management of epilepsy.

The Neurostimulation Appropriateness Consensus Committee (NACC)®: Recommendations for Spinal Cord Stimulation Long-term Outcome Optimization and Salvage Therapy.

INTRODUCTION: The International Neuromodulation Society (INS) has recognized a need to establish best practices for optimizing implantable devices and salvage when ideal outcomes are not realized. This group has established the Neurostimulation Appropriateness Consensus Committee (NACC)® to offer guidance on matters needed for both our members and the broader community of those affected by neuromodulation devices. MATERIALS AND METHODS: The executive committee of the INS nominated faculty for this NACC® publication on the basis of expertise, publications, and career work on the issue. In addition, the faculty was chosen in consideration of diversity and inclusion of different career paths and demographic categories. Once chosen, the faculty was asked to grade current evidence and along with expert opinion create consensus recommendations to address the lapses in information on this topic. RESULTS: The NACC® group established informative and authoritative recommendations on the salvage and optimization of care for those with indwelling devices. The recommendations are based on evidence and expert opinion and will be expected to evolve as new data are generated for each topic. CONCLUSIONS: NACC® guidance should be considered for any patient with less-than-optimal outcomes with a stimulation device implanted for treating chronic pain. Consideration should be given to these consensus points to salvage a potentially failed device before explant.

The Neurostimulation Appropriateness Consensus Committee (NACC)®: Recommendations for the Mitigation of Complications of Neurostimulation.

INTRODUCTION: The International Neuromodulation Society convened a multispecialty group of physicians based on expertise and international representation to establish evidence-based guidance on the mitigation of neuromodulation complications. This Neurostimulation Appropriateness Consensus Committee (NACC)® project intends to update evidence-based guidance and offer expert opinion that will improve efficacy and safety. MATERIALS AND METHODS: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from 2017 (when NACC last published guidelines) to October 2023. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on the strength of evidence or consensus when evidence was scant. RESULTS: The NACC examined the published literature and established evidence- and consensus-based recommendations to guide best practices. Additional guidance will occur as new evidence is developed in future iterations of this process. CONCLUSIONS: The NACC recommends best practices regarding the mitigation of complications associated with neurostimulation to improve safety and efficacy. The evidence- and consensus-based recommendations should be used as a guide to assist decision-making when clinically appropriate.

The Polyanalgesic Consensus Conference (PACC)®: Intrathecal Drug Delivery Guidance on Safety and Therapy Optimization When Treating Chronic Noncancer Pain.

INTRODUCTION: The International Neuromodulation Society convened a multispecialty group of physicians and scientists based on expertise with international representation to establish evidence-based guidance on intrathecal drug delivery in treating chronic pain. This Polyanalgesic Consensus Conference (PACC)® project, created more than two decades ago, intends to provide evidence-based guidance for important safety and efficacy issues surrounding intrathecal drug delivery and its impact on the practice of neuromodulation. MATERIALS AND METHODS: Authors were chosen on the basis of their clinical expertise, familiarity with the peer-reviewed literature, research productivity, and contributions to the neuromodulation literature. Section leaders supervised literature searches of MEDLINE, BioMed Central, Current Contents Connect, Embase, International Pharmaceutical Abstracts, Web of Science, Google Scholar, and PubMed from 2017 (when PACC® last published guidelines) to the present. Identified studies were graded using the United States Preventive Services Task Force criteria for evidence and certainty of net benefit. Recommendations are based on the strength of evidence or consensus when evidence is scant. RESULTS: The PACC® examined the published literature and established evidence- and consensus-based recommendations to guide best practices. Additional guidance will occur as new evidence is developed in future iterations of this process. CONCLUSIONS: The PACC® recommends best practices regarding intrathecal drug delivery to improve safety and efficacy. The evidence- and consensus-based recommendations should be used as a guide to assist decision-making when clinically appropriate.

Boosting Confidence: Enhancing Spinal Cord Stimulator Needle and Lead Placement Through Simulation Training.

Background This pilot study aims to examine the effectiveness of a spinal cord stimulator (SCS) simulator training system in improving the confidence of pain fellows in SCS placement. Methodology Five Ukrainian physicians (neurologists, neurosurgeons, and an anesthesiologist) completed a 10-item survey regarding their confidence in various aspects of SCS placement and their opinions on how effective SCS models were for educational purposes. After placing SCS leads using the SCS simulator, the physicians took the same survey again. The Mann-Whitney U test was used to determine if there was a significant difference in total scores pre and post-simulator training. The software PAST (PAleontological STatistics) was used for statistical analysis. Results Overall, five participants had a 38% statistically significant increase in survey scores before and after the intervention (mean: 4.2 vs. 6.2, p = 0.0055). With regards to each item of the survey, participants had a significantly increased confidence in driving leads (2.6 vs. 5.2, p = 0.008) and in overall technical skills for the SCS procedure after the training (2.8 vs. 5.2, p = 0.0188). Although the other eight survey items were not statistically significant (p > 0.05), participants had a 28% increase in confidence when inserting epidural needles, a 20% increase in interpreting simulated X-rays, a 32% increase in navigating challenging anatomical variations, a 12% increase in identifying key anatomical landmarks, a 20% increase in ensuring the correct placement of the lead, or a 53% increase in preparedness for performing an SCS procedure in a real clinical setting. The participant's perspective on how valuable the stimulator training was for enhancing procedural skills increased by 38% and how well the simulator replicated real-life SCS procedure increased by 52%, although both were statistically insignificant (p > 0.05). Conclusions This pilot study shows that the utilization of simulated neuromodulation training is a viable means of augmenting neuromodulation education by increasing physician's confidence in aspects of the SCS placement procedure. The extent to which simulator training improves procedural skills in a real-life SCS placement needs to be investigated further.

Exploring the Patient Experience and Perspective in Virtual-First Primary Care: A Cross-Sectional Study from an Integrated Health System.

Background: Little is known about the implication of launching virtual-first primary care (VPC) in a health system. Our experience and survey can guide others to establish their virtual-first programs. This study examines implementation, patient perspectives, and satisfaction with VPC at University of Pittsburgh Medical Center (UPMC). Methods: We conducted a Web-based survey to examine factors associated with the likelihood of early adoption and continued use of VPC. We used bivariate comparisons and cluster analysis to evaluate the results. The survey was sent to 1,420 patients seen between August 2022 and January 2023. Responses related to demographics, doctor-patient relations, savings, experience, and future preferences of use were aggregated. To evaluate the relationship between demographics and survey responses, we conducted univariate analysis. Results: Females and patients between 40 and 50 years of age were the primary users and indicated the most interest in continued use. Health insurance status seems not to be a significant predictor in the selection and use of VPC. Most (78%) felt that the physician-patient relationship was unimpaired. The survey showed that 90% of patients saved time by using VPC, and 66% reported saving money on tolls, childcare, or gasoline. Only 13% reported not wanting to continue VPC. Discussion: A majority of surveyed patients felt the doctor-patient relationship was not negatively affected in VPC. VPC programs can be implemented with high patient satisfaction in an integrated health system. VPC is acceptable to most patients, and further expansion of the model is warranted.

Analysis of Blood Cultures from Major Burns Patients in a Tertiary Care Burn Unit in Oman.

Objectives: This study aimed to review the blood stream infections of major burn patients in a tertiary care burn unit to determine the most prevalent infecting organisms in order to have a better empirical therapy protocol. Methods: This retrospective study analysed the blood stream infection of 155 major burn (>20% Total Body Surface Area [TBSA]) patients in Khoula Hospital, Muscat, Oman between January 2014 to December 2019. Results: The median age was 33 years and 57.42% of patients were male. The median TBSA was 38%, mortality was 25.16% and 50.9% of patients had positive blood cultures. The expired patients had higher TBSAs, Abbreviated Burns Severity Index scores and earlier first positive blood cultures. Candida was commonly grown in all the blood cultures, but the most prevalent organisms were Acinetobacter, Staphylococci, Klebsiella, Enterococcus and Pseudomonas. All Acinetobacter species are multidrug resistant. Of the 17 patients who had Kelbsiella grown in the blood culture, 8 grew multidrug-resistant Klebsiella. Only 4 patients' blood cultures grew methicillin-resistant Staphylococcus aureus. The number of blood culture samples taken ranged between 1-28 (median = 6). The first positive blood culture showed that Staphylococcus epidermidis and Acinetobacter were the most common infecting organisms. Conclusions: Multidrug-resistant Acinetobacter was the most predominant microorganism grown from the blood cultures of major burn patients in a tertiary care burn unit. Empirical therapy should include antibiotics that are effective against this organism to reduce the mortality.

A Definition of Neuromodulation and Classification of Implantable Electrical Modulation for Chronic Pain.

OBJECTIVES: Neuromodulation therapies use a variety of treatment modalities (eg, electrical stimulation) to treat chronic pain. These therapies have experienced rapid growth that has coincided with escalating confusion regarding the nomenclature surrounding these neuromodulation technologies. Furthermore, studies are often published without a complete description of the effective stimulation dose, making it impossible to replicate the findings. To improve clinical care and facilitate dissemination among the public, payors, research groups, and regulatory bodies, there is a clear need for a standardization of terms. APPROACH: We formed an international group of authors comprising basic scientists, anesthesiologists, neurosurgeons, and engineers with expertise in neuromodulation. Because the field of neuromodulation is extensive, we chose to focus on creating a taxonomy and standardized definitions for implantable electrical modulation of chronic pain. RESULTS: We first present a consensus definition of neuromodulation. We then describe a classification scheme based on the 1) intended use (the site of modulation and its indications) and 2) physical properties (waveforms and dose) of a neuromodulation therapy. CONCLUSIONS: This framework will help guide future high-quality studies of implantable neuromodulatory treatments and improve reporting of their findings. Standardization with this classification scheme and clear definitions will help physicians, researchers, payors, and patients better understand the applications of implantable electrical modulation for pain and guide informed treatment decisions.

Phytochemical screening and evaluation of antioxidant, total phenolic and flavonoid contents in various weed plants associated with wheat crops

Abstract This study explores the antioxidant activity, phytochemical screening, total phenolic and flavonoids contents in the extracts of four locally available weeds plants namely Convolvulus arvensis, Chenopodium murale, Avena fatua and Phalaris minor with different solvents. The antioxidant activities of these extracts were determined via various in-vitro methods such as total antioxidant activity (TAA), reducing power (RP), DPPH (2,2-Diphenyl-1-Picrylhydrazyl) free radical scavenging and hydrogen peroxide scavenging assays. Phytochemical screening was performed both qualitatively as well as quantitatively. Total phenolic content (TPC) and total flavonoid content (TFC) were determined through Folin- Ciocalteu reagent and aluminium chloride methods respectively. Methanol-chloroform solvent showed the presence of a high amount of TPC in milligram of gallic acid equivalent per gram of dry weight (mg of GAE/g of DW) in the extracts of all weeds. Their descending sequence was Avena fatua (74.09) Phalaris minor (65.66) Chenopodium murale (64.04) Convolvulus arvensis (61.905), while, chloroform solvent found to be best solvent for the extraction of TFC. Methanol-chloroform solvent was also found to be best solvent for TAA (Total antioxidant activity assay) which showed values in milligram of ascorbic acid equivalent per gram of dry weight (mg of AAE /g of DW), for DPPH scavenging activity, reducing power (antioxidant activity) and hydrogen peroxide scavenging activity. Phytochemical screening indicated the presence of polyphenols, flavonoids, tannins, saponins, alkaloids and glycosides in these weeds.

Resumo Este estudo investiga a atividade antioxidante, a triagem fitoquímica, os teores de fenólicos totais e de flavonoides nos extratos de quatro plantas daninhas disponíveis localmente, quais sejam, Convolvulus arvensis, Chenopodium murale, Avena fatua e Phalaris minor com diferentes solventes. As atividades antioxidantes desses extratos foram determinadas por meio de vários métodos in vitro, tais como atividade antioxidante total (TAA), poder redutor (RP), sequestro de radicais livres DPPH (2,2-Difenil-1-Picril-hidrazil) e ensaios de sequestro de peróxido de hidrogênio. A triagem fitoquímica foi realizada tanto qualitativamente quanto quantitativamente. O teor de fenólicos totais (TPC) e o teor de flavonoides totais (TFC) foram determinados pelos métodos do reagente de Folin-Ciocalteu e do cloreto de alumínio, respectivamente. O solvente metanol-clorofórmio mostrou a presença de elevada quantidade de TPC em miligramas de ácido gálico equivalente por grama de peso seco (mg de GAE/g de DW) nos extratos de todas as plantas daninhas. Sua sequência descendente foi Avena fatua (74,09) Phalaris minor (65,66) Chenopodium murale (64,04) Convolvulus arvensis (61,905), enquanto o solvente clorofórmio foi o melhor solvente para a extração de TFC. O solvente metanol-clorofórmio também foi considerado o melhor solvente para AAT (ensaio de atividade antioxidante total), que apresentou valores em miligramas de equivalente de ácido ascórbico por grama de peso seco (mg de AAE/g de DW), para atividade sequestrante de DPPH, RP (atividade antioxidante) e atividade de sequestro de peróxido de hidrogênio. A triagem fitoquímica indicou a presença de polifenóis, flavonoides, taninos, saponinas, alcaloides e glicosídeos nessas plantas daninhas.

Congress of Neurological Surgeons Systematic Review and Evidence-Based Guidelines for Occipital Nerve Stimulation for the Treatment of Patients With Medically Refractory Occipital Neuralgia: Update.

BACKGROUND: The Guidelines Task Force conducted a systematic review of the relevant literature on occipital nerve stimulation (ONS) for occipital neuralgia (ON) to update the original 2015 guidelines to ensure timeliness and accuracy for clinical practice. OBJECTIVE: To conduct a systematic review of the literature and update the evidence-based guidelines on ONS for ON. METHODS: The Guidelines Task Force conducted another systematic review of the relevant literature, using the same search terms and strategies used to search PubMed and Embase for relevant literature. The updated search included studies published between 1966 and January 2023. The same inclusion/exclusion criteria as the original guideline were also applied. Abstracts were reviewed, and relevant full text articles were retrieved and graded. Of 307 articles, 18 were retrieved for full-text review and analysis. Recommendations were updated according to new evidence yielded by this update . RESULTS: Nine studies were included in the original guideline, reporting the use of ONS as an effective treatment option for patients with medically refractory ON. An additional 6 studies were included in this update. All studies in the original guideline and this current update provide Class III evidence. CONCLUSION: Based on the availability of new literature, the current article is a minor update only that does not result in modification of the prior recommendations: Clinicians may use ONS as a treatment option for patients with medically refractory ON.

Conversion of Laparoscopic to Open Cholecystectomy: Experience in A Tertiary Care Hospital.

Now-a-days Laparoscopic cholecystectomy is regarded as the gold standard treatment for benign gallbladder disease but in certain situations conversion to open cholecystectomy is extremely important for the safety of the patient. The objective of this study was to evaluate the reason for conversion of this operation to open surgery. This prospective study was carried out on 392 patients in a single unit of Department of Surgery, Bangabandhu Sheikh Mujib Medical University, Dhaka, Bangladesh and in a private hospital from July 2013 to December 2018. Maximum (28.3%) patients were 31-40 years age group. Majority (75.3%) was female and 24.7% were male. It was observed that only 2.1% were converted due to dense adhesion (n=3), severe inflammation (n=2), difficult to define anatomy of Calot's triangle (n=2) and Mirizzi syndrome (n=1). Meticulous dissection and proper case selection can reduce the rate of conversion to open surgery.

Commissioning, clinical implementation, and initial experience with a new brain tumor treatment package on a low-field MR-linac.

To evaluate the image quality, dosimetric properties, setup reproducibility, and planar cine motion detection of a high-resolution brain coil and integrated stereotactic brain immobilization system that constitute a new brain treatment package (BTP) on a low-field magnetic resonance imaging (MRI) linear accelerator (MR-linac). Image quality of the high-resolution brain coil was evaluated with the 17 cm diameter spherical phantom and the American College of Radiology (ACR) Large MRI Phantom. Patient imaging studies approved by the institutional review board (IRB) assisted in selecting image acquisition parameters. Radiographic and dosimetric evaluation of the high-resolution brain coil and the associated immobilization devices was performed using dose calculations and ion chamber measurements. End-to-end testing was performed simulating a cranial lesion in a phantom. Inter-fraction setup variability and motion detection tests were evaluated on four healthy volunteers. Inter-fraction variability was assessed based on three repeat setups for each volunteer. Motion detection was evaluated using three-plane (axial, coronal, and sagittal) MR-cine imaging sessions, where volunteers were asked to perform a set of specific motions. The images were post-processed and evaluated using an in-house program. Contrast resolution of the high-resolution brain coil is superior to the head/neck and torso coils. The BTP receiver coils have an average HU value of 525 HU. The most significant radiation attenuation (3.14%) of the BTP, occurs through the lateral portion of the overlay board where the high-precision lateral-profile mask clips attach to the overlay. The greatest inter-fraction setup variability occurred in the pitch (average 1.08 degree) and translationally in the superior/inferior direction (average 4.88 mm). Three plane cine imaging with the BTP was able to detect large and small motions. Small voluntary motions, sub-millimeter in magnitude (maximum 0.9 mm), from motion of external limbs were detected. Imaging tests, inter-fraction setup variability, attenuation, and end-to-end measurements were quantified and performed for the BTP. Results demonstrate better contrast resolution and low contrast detectability that allows for better visualization of soft tissue anatomical changes relative to head/neck and torso coil systems.

Centrality measures of financial system interconnectedness: A multiple crises study.

We explore how asset returns could be a good proxy to detect interlinkages in the financial system. This paper employs a US dataset for the 2002-2021 period. Pairwise returns correlation indicate the interconnectedness at the preliminary stage. The Principal Component Analysis captures a significant portion of variance and detects the co-movement and highly connected state of the financial market during crises. Granger centrality tested with pairwise directional variance decomposition indicates the importance of banks and insurance companies in the US financial system. This paper recommends policymakers use multiple network models to validate and calibrate the SIFIs list.

Effects of Age, Gender and Soil-Transmitted Helminth Infection on Prevalence of Plasmodium Infection among Population Living in Bata District, Equatorial Guinea.

INTRODUCTION: Malaria and soil-transmitted helminth (STH) co-infection is an important parasitic infection affecting populations in co-endemic countries including Equatorial Guinea. To date, the health impact of STH and malaria co-infection is inconclusive. The current study aimed to report the malaria and STH infection epidemiology in the continental region of Equatorial Guinea. METHODS: We performed a cross-sectional study between October 2020 and January 2021 in the Bata district of Equatorial Guinea. Participants aged 1-9 years, 10-17 years and above 18 were recruited. Fresh venous blood was collected for malaria testing via mRDTs and light microscopy. Stool specimens were collected, and the Kato-Katz technique was used to detect the presence of Ascaris lumbricoides, Trichuris trichiura, hookworm spp. and intestinal Schistosoma eggs. RESULTS: A total of 402 participants were included in this study. An amount of 44.3% of them lived in urban areas, and only 51.9% of them reported having bed nets. Malaria infections were detected in 34.8% of the participants, while 50% of malaria infections were reported in children aged 10-17 years. Females had a lower prevalence of malaria (28.8%) compared with males (41.7%). Children of 1-9 years carried more gametocytes compared with other age groups. An amount of 49.3% of the participants infected with T. trichiura had malaria parasites compared with those infected with A. lumbricoides (39.6%) or both (46.8%). CONCLUSIONS: The overlapping problem of STH and malaria is neglected in Bata. The current study forces the government and other stakeholders involved in the fight against malaria and STH to consider a combined control program strategy for both parasitic infections in Equatorial Guinea.

Libyan Healthcare Professionals', Patients' and Caregivers' Perceptions and Religious Beliefs about Cancer Pain and its Management: A Descriptive Qualitative Study.

Cancer pain remains a significant problem worldwide. It is often undertreated and presents in about half of cancer patients. Although several guidelines and pharmacological interventions for cancer pain management (CPM) exist, inadequate assessment and undertreatment of cancer pain are well-documented globally, especially in developing countries, including Libya. Perceptions, cultural and religious beliefs of healthcare professionals (HCP), patients, and caregivers about cancer pain and opioids are reported as barriers to CPM globally. This qualitative descriptive study aimed to explore Libyan HCPs', patients', and caregivers' views and religious beliefs about CPM and involved semi-structured interviews with 36 participants: 18 Libyan cancer patients, 6 caregivers, and 12 Libyan HCPs. Thematic analysis was used to analyse the data. Patients, caregivers, and newly qualified HCPs were concerned about poor tolerance and drug addiction. HCPs perceived a lack of policies and guidelines, pain rating scales, and professional education and training as CPM barriers. Some patients were unable to pay for medicines if they faced financial difficulties. Instead, patients and caregivers emphasised religious and cultural beliefs for managing cancer pain, including the use of the Qur'an and cautery. Our results suggest that religious and cultural beliefs, lack of knowledge and training in CPM among HCPs, and economic and Libyan healthcare system-related factors negatively affect CPM in Libya.

Impact of MRI resolution for Linac-based stereotactic radiosurgery.

Objective: Magnetic resonance imaging (MRI) is a standard imaging modality in intracranial stereotactic radiosurgery (SRS) for defining target volumes. However, wide disparities in MRI resolution exist, which could directly impact accuracy of target delineation. Here, sequences with various MRI resolution were acquired on phantoms to evaluate the effect on volume definition and dosimetric consequence for cranial SRS. Materials/Methods: Four T1-weighted MR sequences with increasing 3D resolution were compared, including two Spin Echo (SE) 2D acquisitions with 5mm and 3mm slice thickness (SE5mm, SE3mm) and two gradient echo 3D acquisitions (TFE, BRAVO). The voxel sizes were 0.4×0.4×5.0, 0.5×0.5×3.0, 0.9×0.9×1.25, and 0.4×0.4×0.5 mm3, respectively. Four phantoms with simulated lesions of different shape and volume (range, 0.53-25.0 cm3) were imaged, resulting in 16 total sets of MRIs. Four radiation oncologists provided contours on individual MR image set. All observer contours were compared with ground truth, defined on CT image according to the absolute dimensions of the target structure, using Dice similarity coefficient (DSC), Hausdorff distance (HD), mean distance-to-agreement (MDA), and the ratio between reconstructed and true volume (Ratiovol ). For dosimetric consequence, SRS plans targeting observer volumes were created. The true Paddick conformity index ( C I p a d d i c k t r u e ), calculated with true target volume, was correlated with quality of observer volume. Results: All measures of observer contours improved as increasingly higher MRI resolution was provided from SE5mm to BRAVO. The improvement in DSC, HD and MDA was statistically significant (p<0.01). Dosimetrically, C I p a d d i c k t r u e   strongly correlated with DSC of the planning observer volume (Pearson's r=0.94, p<0.00001). Conclusions: Significant improvement in target definition and reduced inter-observer variation was observed as the MRI resolution improved, which also improved the quality of SRS plans. Results imply that high resolution 3D MR sequences should be used to minimize potential errors in target definition, and multi-slice 2D sequences should be avoided.