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Michael C. Dewan, Justin Onen, Hansen Bow, Peter Ssenyonga, Charles Howard, and Benjamin C. Warf

There is inadequate pediatric neurosurgical training to meet the growing burden of disease in low- and middle-income countries (LMIC). Subspecialty expertise in the management of hydrocephalus and spina bifida—two of the most common pediatric neurosurgical conditions—offers a high-yield opportunity to mitigate morbidity and avoid unnecessary death. The CURE Hydrocephalus and Spina Bifida (CHSB) fellowship offers an intensive subspecialty training program designed to equip surgeons from LMIC with the state-of-the-art surgical skills and equipment to most effectively manage common neurosurgical conditions of childhood. Prospective fellows and their home institution undergo a comprehensive evaluation before being accepted for the 8-week training period held at CURE Children’s Hospital of Uganda (CCHU) in Mbale, Uganda. The fellowship combines anatomy review, treatment paradigms, a flexible endoscopic simulation lab, daily ward and ICU rounds, radiology rounds, and clinic exposure. The cornerstone of the fellowship is the unique operative experience that includes a high volume of endoscopic third ventriculostomy with choroid plexus cauterization, myelomeningocele closure, and ventriculoperitoneal shunting, among many other procedures performed at CCHU. Upon completion, fellows return to their home institution to establish or rejuvenate a robust pediatric practice as part of a worldwide network of CHSB trainees committed to the care of underserved children. To date, the fellowship has graduated 33 surgeons from 20 different LMIC who are independently performing thousands of hydrocephalus and spina bifida operations each year.

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Edith Mbabazi-Kabachelor, Meghal Shah, Kerry A. Vaughan, John Mugamba, Peter Ssenyonga, Justin Onen, Esther Nalule, Kush Kapur, and Benjamin C. Warf

OBJECTIVE

Clinical and economic repercussions of ventricular shunt infections are magnified in low-resource countries. The efficacy of antibiotic-impregnated shunts in this setting is unclear. A previous retrospective cohort study comparing the Bactiseal Universal Shunt (BUS) and the Chhabra shunt provided clinical equipoise; thus, the authors conducted this larger randomized controlled trial in Ugandan children requiring shunt placement for hydrocephalus to determine whether there was, in fact, any advantage of one shunt over the other.

METHODS

Between April 2013 and September 2016, the authors randomly assigned children younger than 16 years of age without evidence of ventriculitis to either BUS or Chhabra shunt implantation in this single-blind randomized controlled trial. The primary outcome was shunt infection, and secondary outcomes included reoperation and death. The minimum follow-up was 6 months. Time to outcome was assessed using the Kaplan-Meier method. The significance of differences was tested using Wilcoxon rank-sum, chi-square, Fisher’s exact, and t-tests.

RESULTS

Of the 248 patients randomized, the BUS was implanted in 124 and the Chhabra shunt in 124. There were no differences between the groups in terms of age, sex, or hydrocephalus etiology. Within 6 months of follow-up, there were 14 infections (5.6%): 6 BUS (4.8%) and 8 Chhabra (6.5%; p = 0.58). There were 14 deaths (5.6%; 5 BUS [4.0%] vs 9 Chhabra [7.3%], p = 0.27) and 30 reoperations (12.1%; 15 BUS vs 15 Chhabra, p = 1.00). There were no significant differences in the time to primary or secondary outcomes at 6 months’ follow-up (p = 0.29 and 0.17, respectively, Wilcoxon rank-sum test).

CONCLUSIONS

Among Ugandan infants, BUS implantation did not result in a lower incidence of shunt infection or other complications. Any recommendation for a more costly standard of care in low-resource countries must have contextually relevant, evidence-based support.

Clinical trial registration no.: PACTR201804003240177 (http://www.pactr.org/)

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Jessica R. Lane, Paddy Ssentongo, Mallory R. Peterson, Joshua R. Harper, Edith Mbabazi-Kabachelor, John Mugamba, Peter Ssenyonga, Justin Onen, Ruth Donnelly, Jody Levenbach, Venkateswararao Cherukuri, Vishal Monga, Abhaya V. Kulkarni, Benjamin C. Warf, and Steven J. Schiff

OBJECTIVE

This study investigated the incidence of postoperative subdural collections in a cohort of African infants with postinfectious hydrocephalus. The authors sought to identify preoperative factors associated with increased risk of development of subdural collections and to characterize associations between subdural collections and postoperative outcomes.

METHODS

The study was a post hoc analysis of a randomized controlled trial at a single center in Mbale, Uganda, involving infants (age < 180 days) with postinfectious hydrocephalus randomized to receive either an endoscopic third ventriculostomy plus choroid plexus cauterization or a ventriculoperitoneal shunt. Patients underwent assessment with the Bayley Scales of Infant and Toddler Development, Third Edition (Bayley-III; sometimes referred to as BSID-III) and CT scans preoperatively and then at 6, 12, and 24 months postoperatively. Volumes of brain, CSF, and subdural fluid were calculated, and z-scores from the median were determined from normative curves for CSF accumulation and brain growth. Linear and logistic regression models were used to characterize the association between preoperative CSF volume and the postoperative presence and size of subdural collection 6 and 12 months after surgery. Linear regression and smoothing spline ANOVA were used to describe the relationship between subdural fluid volume and cognitive scores. Causal mediation analysis distinguished between the direct and indirect effects of the presence of a subdural collection on cognitive scores.

RESULTS

Subdural collections were more common in shunt-treated patients and those with larger preoperative CSF volumes. Subdural fluid volumes were linearly related to preoperative CSF volumes. In terms of outcomes, the Bayley-III cognitive score was linearly related to subdural fluid volume. The distribution of cognitive scores was significantly different for patients with and those without subdural collections from 11 to 24 months of age. The presence of a subdural collection was associated with lower cognitive scores and smaller brain volume 12 months after surgery. Causal mediation analysis demonstrated evidence supporting both a direct (76%) and indirect (24%) effect (through brain volume) of subdural collections on cognitive scores.

CONCLUSIONS

Larger preoperative CSF volume and shunt surgery were found to be risk factors for postoperative subdural collection. The size and presence of a subdural collection were negatively associated with cognitive outcomes and brain volume 12 months after surgery. These results have suggested that preoperative CSF volumes could be used for risk stratification for treatment decision-making and that future clinical trials of alternative shunt technologies to reduce overdrainage should be considered.

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Claire Karekezi, Abdeslam El Khamlichi, Abdessamad El Ouahabi, Najia El Abbadi, Semevo Alidegnon Ahokpossi, Kodjo Mensah Hobli Ahanogbe, Ibrahima Berete, Soueilem Mohamed Bouya, Oumar Coulibaly, Ibrahim Dao, Ben Ousmanou Djoubairou, Agbeko Achille Komlan Doleagbenou, Komi Prosper Egu, Hugues Brieux Ekouele Mbaki, Sinclair Brice Kinata-Bambino, Laminou Mahamane Habibou, Adio Nabil Mousse, Trésor Ngamasata, Jeff Ntalaja, Justin Onen, Kisito Quenum, Diawara Seylan, Youssouf Sogoba, Franco Servadei, and Isabelle M. Germano

OBJECTIVE

Sub-Saharan Africa (SSA) represents 17% of the world’s land, 14% of the population, and 1% of the gross domestic product. Previous reports have indicated that 81/500 African neurosurgeons (16.2%) worked in SSA—i.e., 1 neurosurgeon per 6 million inhabitants. Over the past decades, efforts have been made to improve neurosurgery availability in SSA. In this study, the authors provide an update by means of the polling of neurosurgeons who trained in North Africa and went back to practice in SSA.

METHODS

Neurosurgeons who had full training at the World Federation of Neurosurgical Societies (WFNS) Rabat Training Center (RTC) over the past 16 years were polled with an 18-question survey focused on demographics, practice/case types, and operating room equipment availability.

RESULTS

Data collected from all 21 (100%) WFNS RTC graduates showed that all neurosurgeons returned to work to SSA in 12 different countries, 90% working in low-income and 10% in lower-middle-income countries, defined by the World Bank as a Gross National Income per capita of ≤ US$995 and US$996–$3895, respectively. The cumulative population in the geographical areas in which they practice is 267 million, with a total of 102 neurosurgeons reported, resulting in 1 neurosurgeon per 2.62 million inhabitants. Upon return to SSA, WFNS RTC graduates were employed in public/private hospitals (62%), military hospitals (14.3%), academic centers (14.3%), and private practice (9.5%). The majority reported an even split between spine and cranial and between trauma and elective; 71% performed between 50 and more than 100 neurosurgical procedures/year. Equipment available varied across the cohort. A CT scanner was available to 86%, MRI to 38%, surgical microscope to 33%, endoscope to 19.1%, and neuronavigation to 0%. Three (14.3%) neurosurgeons had access to none of the above.

CONCLUSIONS

Neurosurgery availability in SSA has significantly improved over the past decade thanks to the dedication of senior African neurosurgeons, organizations, and volunteers who believed in forming the new neurosurgery generation in the same continent where they practice. Challenges include limited resources and the need to continue expanding efforts in local neurosurgery training and continuing medical education. Focus on affordable and low-maintenance technology is needed.