A framework for advancing sustainable magnetic resonance imaging access in Africa.

Magnetic resonance imaging (MRI) technology has profoundly transformed current healthcare systems globally, owing to advances in hardware and software research innovations. Despite these advances, MRI remains largely inaccessible to clinicians, patients, and researchers in low-resource areas, such as Africa. The rapidly growing burden of noncommunicable diseases in Africa underscores the importance of improving access to MRI equipment as well as training and research opportunities on the continent. The Consortium for Advancement of MRI Education and Research in Africa (CAMERA) is a network of African biomedical imaging experts and global partners, implementing novel strategies to advance MRI access and research in Africa. Upon its inception in 2019, CAMERA sets out to identify challenges to MRI usage and provide a framework for addressing MRI needs in the region. To this end, CAMERA conducted a needs assessment survey (NAS) and a series of symposia at international MRI society meetings over a 2-year period. The 68-question NAS was distributed to MRI users in Africa and was completed by 157 clinicians and scientists from across Sub-Saharan Africa (SSA). On average, the number of MRI scanners per million people remained at less than one, of which 39% were obsolete low-field systems but still in use to meet daily clinical needs. The feasibility of coupling stable energy supplies from various sources has contributed to the growing number of higher-field (1.5 T) MRI scanners in the region. However, these systems are underutilized, with only 8% of facilities reporting clinical scans of 15 or more patients per day, per scanner. The most frequently reported MRI scans were neurological and musculoskeletal. The CAMERA NAS combined with the World Health Organization and International Atomic Energy Agency data provides the most up-to-date data on MRI density in Africa and offers a unique insight into Africa's MRI needs. Reported gaps in training, maintenance, and research capacity indicate ongoing challenges in providing sustainable high-value MRI access in SSA. Findings from the NAS and focused discussions at international MRI society meetings provided the basis for the framework presented here for advancing MRI capacity in SSA. While these findings pertain to SSA, the framework provides a model for advancing imaging needs in other low-resource settings.

A novel approach to SBRT patient quality assurance using EPID-based real-time transit dosimetry : A step to QA with in vivo EPID dosimetry.

PURPOSE: Intra- and inter-fraction organ motion is a major concern in stereotactic body radiation therapy (SBRT). It may cause substantial differences between the planned and delivered dose distribution. Such delivery errors may lead to medical harm and reduce life expectancy for patients. The project presented here investigates and improves a rapid method to detect such errors by performing online dose verification through the analysis of electronic portal imaging device (EPID) images. METHODS: To validate the method, a respiratory phantom with inhomogeneous insert was examined under various scenarios: no-error and error-simulated measurements. Simulation of respiratory motions was practiced for target ranges up to 2 cm. Three types of treatment planning technique - 3DCRT (three-dimensional conformal radiation therapy), IMRT (intensity modulated radiation therapy), and VMAT (volumetric modulated arc therapy - were generated for lung SBRT. A total of 54 plans were generated to assess the influence of techniques on the performance of portal dose images. Subsequently, EPID images of 52 SBRT patients were verified. Both for phantom and patient cases, dose distributions were compared using the gamma index method according to analysis protocols in the target volume. RESULTS: The comparison of error-introduced EPID-measured images to reference images showed no significant differences with 3%/3 mm gamma evaluation, though target coverage was strongly underestimated. Gamma tolerance of 2%/2 mm reported noticeable detection in EPID sensitivity for simulated errors in 3DCRT and IMRT techniques. The passing rates for 3DCRT, IMRT, and VMAT with 1%/1 mm in open field were 84.86%, 92.91%, and 98.75%, and by considering MLC-CIAO + 1 cm (threshold 5%), were 68.25%, 83.19%, and 95.29%, respectively. CONCLUSION: This study demonstrates the feasibility of EPID for detecting the interplay effects. We recommend using thin computed tomography slices and adding sufficient tumor margin in order to limit the dosimetric organ motion in hypofractionated irradiation with preserved plan quality. In the presence of respiratory and gastrointestinal motion, tighter criteria and consequently using local gamma evaluation should be considered, especially for VMAT. This methodology offers a substantial step forward in in vivo dosimetry and the potential to distinguish errors depending on the gamma tolerances. Thus, the approach/prototype provides a fast and easy quality assurance procedure for treatment delivery verification.

Stereotactic radiosurgery for facial nerve schwannomas: A preliminary assessment and review of the literature.

OBJECTIVE: Facial nerve schwannomas (FNS) are rare tumors, and their appropriate management remains the subject of considerable debate. This report details the results of a series of patients with FNS treated with stereotactic radiosurgery (SRS) at the University of Virginia. METHODS: We performed a retrospective review of the clinical and imaging outcomes of 5 patients who underwent Gamma Knife RS (GKRS) for small-to-medium-sized (<5 mL) FNS at our institution. The study population consisted of 3 males and 2 females with a median age of 35 years. All patients presented with varying degrees of facial palsy and/or hearing dysfunction. Tumor volumes at GKRS ranged from 0.1 to 5 (median=0.8) mL. The median maximum radiosurgical dose and tumor margin dose were 24 Gy and 12 Gy, respectively. RESULTS: After a median follow-up period of 12 (range, 6-36) months, three tumors were radiographically smaller and two remained stable. Facial function improved in three patients, remained stable in one patient, and slightly declined from House-Brackmann grade I to II in one patient. Hearing function was preserved in three patients and deteriorated in two patients, one from Gardner-Robertson grade I to II and the other from serviceable hearing grade II to III. CONCLUSION: SRS appears to offer a reasonable rate of facial nerve preservation and tumor control for patients with small-to-medium-sized FNS. Considering the published outcomes achieved with resection, RS may be the preferred first-line treatment for these tumors.

Gamma knife radiosurgery for the treatment of gynecologic malignancies metastasizing to the brain: clinical article.

Gynecologic malignancies represent some of the commonest causes of cancer in the female population. Despite their overall high prevalence, gynecologic malignancies have seldom been reported to metastasize to the brain. The incidence of gynecologic cancers spreading to the brain has been rising, and the optimal management of these patients is not well defined. A retrospective analysis of patients treated over the past ten years with gamma knife radiosurgery (GKRS) for metastatic gynecologic cancer to the brain was performed. Radiographic treatment response, tumor control, metastatic disease progression and survival data were analyzed. Eight patients with ovarian cancer, six patients with endometrial cancer and two separates who carried a diagnosis of cervical cancer or leiomyosarcoma harbored metastatic disease to the brain that was treated with GKRS. The median dose to the tumor margin was 20 Gy (range 10-22 Gy), and the median maximum radiosurgical dose was 31 Gy (range 16-52.9 Gy). Tumor control was achieved in all patients who had follow up imaging studies. Patients with ovarian cancer had prolonged median survival following GKRS compared to patients with endometrial cancer (22.3 vs 8.3 months, p = 0.02). The patient with cervical cancer survived 8 months following her GKRS in the setting of metastatic brain tumor progression, whereas the patient with leiomyosarcoma passed away within several weeks of treatment secondary to disseminated extracranial primary disease. GKRS is a safe and effective means of achieving intracranial tumor control for patients with gynecologic cancer that has spread to the brain.

PET imaging for a very early detection of rapid eye movement sleep behaviour disorder and Parkinson's disease - A model-based cost-effectiveness analysis.

Parkinson's disease (PD) is the second most prevalent neurodegenerative condition after Alzheimer's disease and it represents one of the fastest emerging neurological diseases worldwide. PD is usually diagnosed after the third decade of life with symptoms like tremors at rest and muscle stiffness. Rapid Eye Movement sleep behavioral disorder (RBD) is another disorder that is caused by a loss of typical muscle relaxation during sleep with a lot of motor activity. Usually, RBD is strongly associated with PD. Recent studies have demonstrated that PD reduces the life expectancy of patients to 10 and 20 years after being diagnosed. In addition, delayed diagnosis and treatment of these neurological disorders have significant socio-economic impacts on patients, their partners and on the general public. Often, it is not clear about PD associated financial burdens both in low and high-income countries. On the other hand, PD triggers neurological variations that affect differences in the dopamine transporter (DAT) and in glucose metabolism. Therefore, positron emission tomography (PET) using specific DAT radiotracers and fluorine-18 labeled desoxyglucose (FDG) has being considered a key imaging technique that could be applied clinically for the very early diagnosis of RBD and in PD. However, a few myths about PET is that it is very expensive. Here, we looked at the cost of treatment of PD and RBD in relation to early PET imaging. Our finding suggests that PET imaging might also be a cost sparing diagnostic option in the management of patients with PD and RBD, not only for first world countries as it is the case now but also for the third world countries. Therefore, PET is a cost-effective imaging technique for very early diagnostic of RBD and PD.

Enhancing Sleep Quality: Assessing the Efficacy of a Fixed Combination of Linden, Hawthorn, Vitamin B1, and Melatonin.

Sleep is essential for overall health, yet various sleep disorders disrupt normal sleep patterns, affecting duration, quality, and timing. This pilot study investigate the impact of a food supplement (SPINOFF®) on both sleep quality and mental well-being in 41 participants (mean age: 45.3 years). Initial assessments revealed sleep disturbances (Pittsburgh Sleep Quality Index-PSQ-mean score: 8.2) and insomnia symptoms (Insomnia Severity Index-ISI- mean score: 12.7). Mental health assessments showed psychological distress (Dass-21 Depression mean score: 4.2, Anxiety mean score: 6.9, Stress mean score: 11.6, Total mean score: 22.7). This study assessed sleep continuity using Awakenings per Night (ApN) via a smartwatch (HELO HEALTH®) and conducted the study in two phases: baseline (T0) and after 30 days of treatment (T1) (Phase A). No placebo-control was used in this study. After 30 days (Phase B), 21 patients were selected for reassessment. Eleven continued treatment for another 30 days (T2), while ten discontinued. Following the intervention, we observed remarkable improvements in sleep quality and mental distress. The SPINOFF® supplement significantly reduced the PSQI scores (22.4%), indicating enhanced sleep quality. Additionally, there was a 19.6% decrease in ISI scores, demonstrating a reduction in insomnia symptoms. Moreover, overall psychological distress decreased by 19.5% signifying improved psychological well-being. In the second phase, participants who continued treatment experienced more substantial improvements, with a mean decrease of 0.8 points in PSQI scores (±0.9) and a mean decrease of 0.9 points in ISI scores. Our findings suggest that the SPINOFF® supplement has the potential to effectively address both sleep disturbances and psychological distress in our study population.

Challenges and Solutions for Functional Neurosurgery in Developing Countries.

Functional neurosurgery techniques remain integral to the neurosurgical treatment armamentarium but data on global implementation remains scarce. In comparison to high-income countries (HIC), low- and middle-income countries (LMIC) suffer from an increased prevalence of diseases like epilepsy, which may be amenable to functional techniques, and therefore, LMIC may benefit from an increased utilization of these treatment modalities. However, functional techniques tend to be expensive and thus difficult to implement in the LMIC setting. A review was performed to assess the current status of functional neurosurgical techniques in LMIC as a starting point for future initiatives. For methodology, a review of the current body of literature on functional neurosurgery in LMIC was conducted through the United States National Library of Medicine Pubmed search engine. Search terms included "functional neurosurgery," "developing countries," "low and middle income," and other related terms. It was found that though five billion people lack access to safe surgical care, the burden of disease amenable to treatment with functional neurosurgical procedures remains unknown. Increasingly, reports of successful, long-term, international neurosurgical collaborations are being reported, but reports in the sub-field of functional neurosurgery are lacking. In conclusion, awareness of global surgical disparities has increased dramatically while global guidelines for functional techniques are currently lacking. A concerted effort can harness these techniques for wider practice. Partnerships between centers in LMIC and HIC are making progress to better understand the burden of disease in LMIC and to create context-specific solutions for practice in the LMIC setting, but more collaborations are warranted.

Natural and surgical history of Chiari malformation Type I in the pediatric population.

OBJECT The natural and surgical history of Chiari malformation Type I (CM-I) in pediatric patients is currently not well described. In this study the authors discuss the clinical and radiological presentation and outcomes in a large cohort of pediatric CM-I patients treated with either conservative or surgical management. METHODS The authors retrospectively reviewed 95 cases involving pediatric patients with CM-I who presented between 2004 and 2013. The patients ranged in age from 9 months to 18 years (mean 8 years) at presentation. The cohort was evenly split between the sexes. Twenty-five patients underwent posterior fossa decompression (PFD) with either dural splitting or duraplasty. Seventy patients were managed without surgery. Patients were followed radiologically (mean 44.8 months, range 1.2-196.6 months) and clinically (mean 66.3 months, range 1.2-106.5 months). RESULTS Seventy patients were treated conservatively and followed with serial outpatient neurological and radiological examinations, whereas 25 patients were treated with PFD. Of these 25 surgical patients, 11 were treated with duraplasty (complete dural opening) and 14 were treated with a dura-splitting technique (incomplete dural opening). Surgical intervention was associated with better clinical resolution of symptoms and radiological resolution of tonsillar ectopia and syringomyelia (p = 0.0392). Over the course of follow-up, 20 (41.7%) of 48 nonsurgical patients who were symptomatic at presentation experienced improvement in symptoms and 18 (75%) of 24 symptomatic surgical patients showed clinical improvement (p = 0.0117). There was no statistically significant difference in resolution of symptoms between duraplasty and dura-splitting techniques (p = 0.3572) or between patients who underwent tonsillectomy and tonsillopexy (p = 0.1667). Neither of the 2 patients in the conservative group with syrinx at presentation showed radiological evidence of resolution of the syrinx, whereas 14 (87.5%) of 16 patients treated with surgery showed improvement or complete resolution of syringomyelia (p = 0.0392). In the nonsurgical cohort, 3 patients (4.3%) developed new or increased syrinx. CONCLUSIONS The overwhelming majority of CM-I patients (92.9%) managed conservatively do not experience clinical or radiological progression, and a sizeable minority (41.7%) of those who present with symptoms improve. However, appropriately selected symptomatic patients (sleep apnea and dysphagia) and those presenting with syringomyelia should be considered surgical candidates because of the high rates of clinical (75%) and radiological improvement (87.5%).

A cost comparative study of Gamma Knife radiosurgery versus open surgery for intracranial pathology.

Resection is the traditional treatment for common intracranial pathologies including brain metastases, arteriovenous malformations (AVM), and acoustic neuromas. However, more recently Gamma Knife radiosurgery (GKRS; Elekta AB, Stockholm, Sweden) has emerged as an effective, alternative treatment modality. There are limited data investigating the cost effectiveness of these two treatment modalities. In this study, we compare the costs of GKRS and open surgical excision. This was a retrospective study including all patients at a single-institution across a 3 year period with at least 12 months of post-resection follow-up for brain metastases, acoustic neuromas, or AVM. The costs of care were then totaled and compared to known average costs for GKRS at the same institution. The average 12 month costs of treating patients with brain metastases, acoustic neuromas, and AVM using open surgery were USD$55,938, $67,538, and $78,332, respectively. The average 12 month costs of treating brain metastases, acoustic neuromas, and AVM with GKRS were USD$23,069, $37,840, and $46,293, respectively. This shows that GKRS was on average 58.8%, 44.0%, and 40.9% of the cost of open surgery for brain metastases, acoustic neuromas, and AVM, respectively. GKRS is a cost effective, first-line, alternative to open surgery for treatment of brain metastatic lesions, acoustic neuromas, and AVM in selected patients. This result conforms to previous studies, which also demonstrate that radiosurgery is the more cost-effective treatment for brain metastases and acoustic neuromas when patients are well suited for either approach. Further prospective studies are needed to show that this result is valid at other institutions.

Sudden unilateral hearing loss and vascular loop in the internal auditory canal: case report and review of literature.

OBJECTIVE: We present a patient with unilateral sudden sensorineural hearing loss (SSNHL) who was found to have a vascular loop in the ipsilateral internal auditory canal (IAC), and we review the literature regarding this association. Underlying pathophysiologic factors surrounding microvascular compression of the vestibulocochlear nerve are poorly understood and make treatment recommendations, especially the option of microvascular decompression, difficult if not controversial. The current report represents an attempt to understand this clinical entity as discussed in the current literature.Case summary: A 77-year-old female with a long history of progressive right-sided hearing loss and episodic vertigo developed unilateral right SSNHL, tinnitus, vertigo, and disequilibrium. She was originally diagnosed with a vestibular schwannoma on magnetic resonance imaging (MRI) and was referred to our institution for Gamma Knife radiosurgery. Repeat MRI demonstrated a loop of the anterior inferior cerebellar artery (AICA) compressing the vestibulocochlear nerve within the right IAC. There was no evidence of a schwannoma on the repeat MRI. She was not offered radiosurgery, and she elected conservative management. CONCLUSION: Vascular compression of cranial nerves can lead to neuronal dysfunction, and this has been rarely described in patients involving the vestibulocochlear nerve complex. There is evidence that microvascular decompression (MVD) of the vestibulocochlear nerve can be effective in selected patients who exhibit pulsatile tinnitus or disabling positional vertigo in the setting of a vascular loop within the ipsilateral IAC, but available evidence at this time does not support MVD for SSNHL.

Gamma Knife radiosurgery of large skull base meningiomas.

OBJECT: Stereotactic radiosurgery (SRS) has become a common treatment modality for intracranial meningiomas. Skull base meningiomas greater than 8 cm3 in volume have been found to have worse outcomes following SRS. When symptomatic, patients with these tumors are often initially treated with resection. For tumors located in close proximity to eloquent structures or in patients unwilling or unable to undergo a resection, SRS may be an acceptable therapeutic approach. In this study, the authors review the SRS outcomes of skull base meningiomas greater than 8 cm3 in volume, which corresponds to a lesion with an approximate diameter of 2.5 cm. METHODS: The authors reviewed the data in a prospectively compiled database documenting the outcomes of 469 patients with skull base meningiomas treated with single-session Gamma Knife radiosurgery (GKRS). Seventy-five patients had tumors greater than 8 cm3 in volume, which was defined as a large tumor. All patients had a minimum follow-up of 6 months, but patients were included if they had a complication at any time point. Thirty patients were treated with upfront GKRS, and 45 were treated following microsurgery. Patient and tumor characteristics were assessed to determine predictors of new or worsening neurological function and tumor progression following GKRS. RESULTS: After a mean follow-up of 6.5 years (range 0.5-21 years), the tumor volume was unchanged in 37 patients (49%), decreased in 26 patients (35%), and increased in 12 patients (16%). Actuarial rates of progression-free survival at 3, 5, and 10 years were 90.3%, 88.6%, and 77.2%, respectively. Four patients had new or worsened edema following GKRS, but preexisting edema decreased in 3 patients. In Cox multivariable analysis, covariates associated with tumor progression were 1) presentation with any cranial nerve (CN) deficit from III to VI (hazard ratio [HR] 3.78, 95% CI 1.91-7.45; p<0.001), history of radiotherapy (HR 12.06, 95% CI 2.04-71.27; p=0.006), and tumor volume greater than 14 cm3 (HR 6.86, 95% CI 0.88-53.36; p=0.066). In those patients with detailed clinical follow-up (n=64), neurological function was unchanged in 37 patients (58%), improved in 16 patients (25%), and deteriorated in 11 patients (17%). In multivariate analysis, the factors predictive of new or worsening neurological function were history of surgery (OR 3.00, 95% CI 1.13-7.95; p=0.027), presentation with any CN deficit from III to VI (OR 3.94, 95% CI 1.49-10.24; p=0.007), and decreasing maximal dose (OR 0.76, 95% CI 0.63-0.93; p=0.007). Tumor progression was present in 64% of patients with new or worsening neurological decline. CONCLUSIONS: Stereotactic radiosurgery affords a reasonable rate of tumor control for large skull base meningiomas and does so with a low incidence of neurological deficits. Those with a tumor less than 14 cm3 in volume and without presenting CN deficit from III to VI were more likely to have effective tumor control.

Improving Brain Tumor Research in Resource-Limited Countries: A Review of the Literature Focusing on West Africa.

Neoplasms of the brain are often overlooked in resource-limited countries. Our literature search via AJOL and PubMed demonstrated that brain tumor research is still a rarity in these regions. We highlight the current status, importance, challenges, and methods of improving brain tumor research in West Africa. We suggest that more attention be given to basic, clinical, and epidemiological brain tumor research by national governments, private organizations, international organizations, non-governmental organizations (NGOs), and individuals in this region.

Whole-sellar stereotactic radiosurgery for functioning pituitary adenomas.

BACKGROUND: Functioning pituitary adenomas (FPAs) can be difficult to delineate on postoperative magnetic resonance imaging, making them difficult targets for stereotactic radiosurgery (SRS). In such cases, radiation delivery to the entire sella has been utilized as a radiosurgical equivalent of a total hypophysectomy. OBJECTIVE: To evaluate the outcomes of a cohort of patients with FPA who underwent SRS to the whole-sellar region. METHODS: This is a retrospective review of patients who underwent whole-sellar SRS for FPA between 1989 and 2012. Sixty-four patients met the inclusion criteria: they were treated with whole-sellar SRS following surgical resection for persistently elevated hormone levels, and (1) no visible lesions on imaging studies and/or (2) tumor infiltration of dura or adjacent venous sinuses observed at the time of a prior resection. The median radiosurgical volume covering sellar structures was 3.2 mL, with a median margin dose of 25 Gy. RESULTS: The median endocrine follow-up was 41 months; 22 (68.8%) patients with acromegaly, 20 (71.4%) patients with Cushing disease, and 2 (50.0%) patients with prolactinoma achieved endocrine remission. The 2-, 4-, and 6-year actuarial remission rates were 54%, 78%, and 87%, respectively. New-onset neurological deficit was found in 4 (6.3%) patients following treatment. New-onset hypopituitarism was observed in 27 (43.5%) patients, with panhypopituitarism in 2 (3.2%). Higher margin/maximum dose were significantly associated with a higher remission rate and development of post-SRS hypopituitarism. CONCLUSION: Whole-sellar SRS for invasive or imaging-negative FPA following failed resection can offer reasonable rates of endocrine remission. Hypopituitarism following whole-sellar SRS is the most common complication.