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Benjamin C. Warf, John Mugamba and Abhaya V. Kulkarni

Object

In Uganda, childhood hydrocephalus is common and difficult to treat. In some children, endoscopic third ventriculostomy (ETV) can be successful and avoid dependence on a shunt. This can be especially beneficial in Uganda, because of the high risk of infection and long-term failure associated with shunting. Therefore, the authors developed and validated a model to predict the chances of ETV success, taking into account the unique characteristics of a large sub-Saharan African population.

Methods

All children presenting with hydrocephalus at CURE Children's Hospital of Uganda (CCHU) between 2001 and 2007 were offered ETV as first-line treatment and were prospectively followed up. A multivariable logistic regression model was built using ETV success at 6 months as the outcome. The model was derived on 70% of the sample (training set) and validated on the remaining 30% (validation set).

Results

Endoscopic third ventriculostomy was attempted in 1406 patients. Of these, 427 were lost to follow-up prior to 6 months. In the remaining 979 patients, the ETV was aborted in 281 due to poor anatomy/visibility and in 310 the ETV failed during the first 6 months. Therefore, a total of 388 of 979 (39.6% and [55.6% of completed ETVs]) procedures were successful at 6 months. The mean age at ETV was 12.6 months, and 57.8% of cases were postinfectious in origin. The authors' logistic regression model contained the following significant variables: patient age at ETV, cause of hydrocephalus, and whether choroid plexus cauterization was performed. In the training set (676 patients) and validation set (303 patients), the model was able to accurately predict the probability of successful ETV (Hosmer-Lemeshow p value > 0.60 and C statistic > 0.70). The authors developed the simplified CCHU ETV Success Score that can be used in the field to predict the probability of ETV success.

Conclusions

The authors' model will allow clinicians to accurately identify children with a good chance of successful outcome with ETV, taking into account the unique characteristics and circumstances of the Ugandan population.

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Lingling Li, Abinash Padhi, Sylvia L. Ranjeva, Sarah C. Donaldson, Benjamin C. Warf, John Mugamba, Derek Johnson, Zephania Opio, Bhushan Jayarao, Vivek Kapur, Mary Poss and Steven J. Schiff

Object

Infantile hydrocephalus in East Africa is predominantly postinfectious. The microbial origins remain elusive, since most patients present with postinfectious hydrocephalus after antecedent neonatal sepsis (NS) has resolved.

Methods

To characterize this syndrome in Ugandan infants, the authors used polymerase chain reaction targeting bacterial 16S ribosomal DNA from CSF to determine if bacterial residua from recent infections were detectable. Bacteria were identified based on the relationship of genetic sequences obtained with reference bacteria in public databases. The authors evaluated samples from patients presenting during dry and rainy seasons and performed environmental sampling in the villages of patients.

Results

Bacterial DNA was recovered from 94% of patients. Gram-negative bacteria in the phylum Proteobacteria were the most commonly detected. Within this phylum, Gammaproteobacteria dominated in patients presenting after infections during the rainy season, and Betaproteobacteria was most common following infections during the dry season. Acinetobacter species were identified in the majority of patients admitted after rainy season infection.

Conclusions

Postinfectious hydrocephalus in Ugandan infants appears associated with predominantly enteric gram-negative bacteria. These findings highlight the need for linking these cases with antecedent NS to develop more effective treatment and prevention strategies.

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Benjamin C. Warf, Vita Stagno and John Mugamba

Object

This study characterizes the first clinical series of encephalocele (EC) from East or Central Africa, and is the largest reported from the African continent. The authors explored survival, the efficacy of primary endoscopic management of associated hydrocephalus, and ethnic differences in EC location.

Methods

One hundred ten consecutive children presented to CURE Children's Hospital of Uganda for treatment of EC over a 9-year period. Clinical data, including patient demographic information, birth date, lesion type (sincipital, parietal, or occipital), operative data, and subsequent course had been entered prospectively into a clinical database. Home visits to update the status of those lost to follow-up were done when possible. With appropriate institutional approvals, the database was reviewed for this retrospective study. Two-tailed probability values calculated using the Fisher exact test were used to assess the significance of differences among groups, with p < 0.05 being considered significant. The Kaplan-Meier method was used for analysis of survival and treatment success probabilities.

Results

There were 53 (48%) occipital, 33 (30%) sincipital, and 24 (22%) parietal lesions. Occipital lesions were significantly more common among children of Bantu origin (p = 0.02). Nilotes demonstrated a roughly equal distribution among sincipital, parietal, and occipital locations. The female/male ratio was 1.2, with no difference between EC types (range 1.0–1.4, p = 0.6–0.8). Of 110 patients, 108 (98%) underwent surgical repair at a median age of 1 month (mean 15.7 months), whereas 2 had treatment for hydrocephalus only. Wound revision was required in 13% of cases. Surgery-related mortality was 3%. One-year and 5-year survival rates were 87% (95% CI 0.79–0.93) and 61% (95% CI 0.51–0.70), respectively. Hydrocephalus required treatment in 32%, and was equally common among the 3 EC types. Thirteen patients were treated with combined endoscopic third ventriculostomy/choroid plexus cauterization (ETV/CPC) and 2 with ETV alone, whereas 18 patients received primary shunt placement. Predicted treatment success at 1 year was 79% for ETV or ETV/CPC (95% CI 0.50–0.94) and 47% for shunt placement (95% CI 0.24–0.71).

Conclusions

Analysis of this first EC series from this region suggests that sincipital lesions are 3 times more common in East than in West Africa. Occipital lesions predominate in patients of Bantu origin, but not among those of Nilotic descent. Hydrocephalus incidence was equally common among different EC types, and endoscopic treatment was more successful (79%) than shunting (47%) at 1 year. The 5-year mortality rate was similar to that for infants with myelomeningocele in Uganda, and more than twice that for their unaffected peers.

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Benjamin C. Warf, Michael Dewan and John Mugamba

Object

Dandy-Walker complex (DWC) is a continuum of congenital anomalies comprising Dandy-Walker malformation (DWM), Dandy-Walker variant (DWV), Blake pouch cyst, and mega cisterna magna (MCM). Hydrocephalus is variably associated with each of these, and DWC-associated hydrocephalus has mostly been treated by shunting, often with 2-compartment shunting. There are few reports of management by endoscopic third ventriculostomy (ETV). This study is the largest series of DWC or DWM-associated hydrocephalus treated by ETV, and the first report of treatment by combined ETV and choroid plexus cauterization (ETV/CPC) in young infants with this association.

Methods

A retrospective review of the CURE Children's Hospital of Uganda clinical database between 2004 and 2010 identified 45 patients with DWC confirmed by CT scanning (25 with DWM, 17 with DWV, and 3 with MCM) who were treated for hydrocephalus by ETV/CPC. Three were excluded because of other potential causes of hydrocephalus (2 postinfectious and 1 posthemorrhagic).

Results

The median age at treatment was 5 months (88% of patients were younger than 12 months). There was a 2.4:1 male predominance among patients with DWV. An ETV/CPC (ETV only in one) was successful with no further operations in 74% (mean and median follow-up 24.2 and 20 months, respectively [range 6–65 months]). The rate of success was 74% for DWM, 73% for DWV, and 100% for MCM; 95% had an open aqueduct, and none required posterior fossa shunting.

Conclusions

Endoscopic treatment of DWC-associated hydrocephalus should be strongly considered as the primary management in place of the historical standard of creating shunt dependence.

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Benjamin C. Warf, Sarah Tracy and John Mugamba

Object

The authors have previously reported on the overall improved efficacy of endoscopic third ventriculostomy (ETV) combined with choroid plexus cauterization (CPC) for infants younger than 1 year of age. In the present study they specifically examined the long-term efficacy of ETV with or without CPC in 35 infants with congenital aqueduct stenosis treated at CURE Children's Hospital of Uganda during the years 2001–2006.

Methods

Infants with congenital aqueductal stenosis were treated during 2 distinct treatment epochs: all underwent ETV alone, and subsequently all underwent ETV-CPC. Prospectively collected data in the clinical database were reviewed for all infants with an age < 1 year who had been treated for hydrocephalus due to congenital aqueductal stenosis. Study exclusion criteria included: 1) a history or findings on imaging or at the time of ventriculoscopy that suggested a possible infectious cause of the hydrocephalus, including scarred choroid plexus; 2) an open aqueduct or an aqueduct obstructed by a membrane or cyst rather than by stenosis; 3) severe malformations of the cerebral hemispheres including hydranencephaly, significant segments of undeveloped brain, or schizencephaly; 4) myelomeningocele, encephalocele, Dandy-Walker complex, or tumor; or 5) previous shunt insertion. The time to treatment failure was analyzed using the Kaplan-Meier method to construct survival curves. Log-rank (Mantel-Cox) and Gehan-Breslow-Wilcoxon tests were used to determine whether differences between the 2 treatment groups were significant.

Results

Thirty-five patients met the study criteria. Endoscopic third ventriculostomy alone was performed in 12 patients (mean age 4.7 months), and combined ETV-CPC was performed in 23 patients (mean age 3.5 months). For patients without treatment failure, the mean and median follow-ups were, respectively, 51.6 and 48.0 months in the ETV group and 31.2 and 26.4 months in the ETV-CPC group. Treatment was successful in 48.6% of the patients who underwent ETV alone, as accurately predicted by the Endoscopic Third Ventriculostomy Success Score (ETVSS), and in 81.9% of the patients who underwent ETV-CPC (p = 0.0119, log-rank test; p = 0.0041, Gehan-Breslow-Wilcoxon test; HR 6.42 [95% CI 1.51–27.36]).

Conclusions

Combined ETV-CPC is significantly superior to ETV alone for infants younger than 1 year of age with congenital aqueductal stenosis. The fact that the outcome for ETV alone was accurately predicted by the ETVSS suggests that these results are applicable in developed countries.

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James Drake

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Benjamin C. Warf, Salman Bhai, Abhaya V. Kulkarni and John Mugamba

Object

It is not known whether previous endoscopic third ventriculostomy (ETV) affects the risk of shunt failure. Different epochs of hydrocephalus treatment at the CURE Children's Hospital of Uganda (CCHU)—initially placing CSF shunts in all patients, then attempting ETV in all patients, and finally attempting ETV combined with choroid plexus cauterization (CPC) in all patients—provided the opportunity to assess whether prior endoscopic surgery affected shunt survival.

Methods

With appropriate institutional approvals, the authors reviewed the CCHU clinical database to identify 2329 patients treated for hydrocephalus from December 2000 to May 2007. Initial ventriculoperitoneal (VP) shunt placement was performed in 900 patients under one of three circumstances: 1) primary nonselective VP shunt placement with no endoscopy (255 patients); 2) VP shunt placement at the time of abandoned ETV attempt (with or without CPC) (370 patients); 3) VP shunt placement subsequent to a completed but failed ETV (with or without CPC) (275 patients). We analyzed time to shunt failure using the Kaplan-Meier method to construct survival curves, Cox proportional hazards regression modeling, and risk-adjusted analyses to account for possible confounding differences among these groups.

Results

Shunt failure occurred in 299 patients, and the mean duration of follow-up for the remaining 601 was 28.7 months (median 18.8, interquartile range 4.1–46.3). There was no significant difference in operative mortality (p = 0.07 by log-rank and p = 0.14 by Cox regression adjusted for age and hydrocephalus etiology) or shunt infection (p = 0.94, log-rank) among the 3 groups. There was no difference in shunt survival between patients treated with primary shunt placement and those who underwent shunt placement at the time of an abandoned ETV attempt (adjusted hazard ratio [HR] 1.14, 95% CI 0.86–1.51, p = 0.35).

Those who underwent shunt placement after a completed but failed ETV (with or without CPC) had a lower risk of shunt failure (p = 0.008, log-rank), with a hazard ratio (adjusted for age at shunting and etiology) of 0.72 (95% CI 0.53–0.98), p = 0.03, compared with those who underwent primary shunt placement without endoscopy; but this was observed only in patients with postinfectious hydrocephalus (PIH) (adjusted HR 0.55, 95% CI 0.36–0.85, p = 0.007), and no effect was apparent for hydrocephalus of noninfectious etiologies (adjusted HR 0.98, 95% CI 0.64–1.50, p = 0.92). Improved shunt survival after failed ETV in the PIH group may be an artifact of selection arising from the inherent heterogeneity of ventricular damage within that group, or a consequence of the timing of shunt placement. The anticipated benefit of CPC in preventing future ventricular catheter obstruction was not observed.

Conclusions

A paradigm for infant hydrocephalus involving intention to treat by ETV with or without CPC had no adverse effect on mortality or on subsequent shunt survival or infection risk. This study failed to demonstrate a positive effect of prior ETV or CPC on shunt survival.

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Jordan D. Lane, John Mugamba, Peter Ssenyonga and Benjamin C. Warf

Object

Antibiotic-impregnated shunts have yet to find widespread use in the developing world, largely due to cost. Given potential differences in the microbial spectrum, their effectiveness in preventing shunt infection for populations in low-income countries may differ and has not been demonstrated. This study is the first to compare the efficacy of a Bactiseal shunt system with a non–antibiotic-impregnated system in a developing country.

Methods

The Bactiseal Universal Shunt (BUS) was placed in 80 consecutive Ugandan children who required a shunt. In this retrospective cohort study, the outcome for that group was compared with the outcome for the immediately preceding 80 consecutive children in whom a Chhabra shunt had been placed. The primary end points were shunt failure, shunt infection, and death. Shunt survival was analyzed using the Kaplan-Meier method. Significance of differences between groups was tested using the log-rank test, chi-square analysis, Fisher's exact test, and t-test.

Results

There was no difference between groups in regard to age, sex, or etiology of hydrocephalus. Mean follow-up for cases of nonfailure was 7.6 months (median 7.8 months, interquartile range 6.5–9.5 months). There was no significant difference between groups for any end point. The BUS group had fewer infections (4 vs 11), but the difference was not significant (p = 0.086, log-rank test). Gram-positive cocci were the most common culturable pathogens in the Chhabra group, while the only positive culture in the BUS group was a gram-negative rod.

Conclusions

These results provide equipoise for a randomized controlled trial in the same population and this has been initiated. It is possible that the observed trends may become significant in a larger study. The more complex task will involve determining not only the efficacy, but also the cost-effectiveness of using antibiotic-impregnated shunt components in limited-resource settings.

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Jason G. Mandell, Kenneth L. Hill, Dan T. D. Nguyen, Kevin W. Moser, Robert E. Harbaugh, James McInerney, Brian Kaaya Nsubuga, John K. Mugamba, Derek Johnson, Benjamin C. Warf, Warren Boling, Andrew G. Webb and Steven J. Schiff

OBJECT

The incidence of temporal lobe epilepsy (TLE) due to mesial temporal sclerosis (MTS) can be high in developing countries. Current diagnosis of MTS relies on structural MRI, which is generally unavailable in developing world settings. Given widespread effects on temporal lobe structure beyond hippocampal atrophy in TLE, the authors propose that CT volumetric analysis can be used in patient selection to help predict outcomes following resection.

METHODS

Ten pediatric patients received preoperative CT scans and temporal resections at the CURE Children's Hospital of Uganda. Engel classification of seizure control was determined 12 months postoperatively. Temporal lobe volumes were measured from CT and from normative MR images using the Cavalieri method. Whole brain and fluid volumes were measured using particle filter segmentation. Linear discrimination analysis (LDA) was used to classify seizure outcome by temporal lobe volumes and normalized brain volume.

RESULTS

Epilepsy patients showed normal to small brain volumes and small temporal lobes bilaterally. A multivariate measure of the volume of each temporal lobe separated patients who were seizure free (Engel Class IA) from those with incomplete seizure control (Engel Class IB/IIB) with LDA (p < 0.01). Temporal lobe volumes also separate normal subjects, patients with Engel Class IA outcomes, and patients with Class IB/IIB outcomes (p < 0.01). Additionally, the authors demonstrated that age-normalized whole brain volume, in combination with temporal lobe volumes, may further improve outcome prediction (p < 0.01).

CONCLUSIONS

This study shows strong evidence that temporal lobe and brain volume can be predictive of seizure outcome following temporal lobe resection, and that volumetric CT analysis of the temporal lobe may be feasible in lieu of structural MRI when the latter is unavailable. Furthermore, since the authors' methods are modality independent, these findings suggest that temporal lobe and normative brain volumes may further be useful in the selection of patients for temporal lobe resection when structural MRI is available.

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Paul J. Marano, Scellig S. D. Stone, John Mugamba, Peter Ssenyonga, Ezra B. Warf and Benjamin C. Warf

OBJECT

The role of reopening an obstructed endoscopic third ventriculostomy (ETV) as treatment for ETV failure is not well defined. The authors studied 215 children with ETV closure who underwent successful repeat ETV to determine the indications, long-term success, and factors affecting outcome.

METHODS

The authors retrospectively reviewed the CURE Children's Hospital of Uganda database from August 2001 through December 2012, identifying 215 children with failed ETV (with or without prior choroid plexus cauterization [CPC]) who underwent reopening of an obstructed ETV stoma. Treatment survival according to sex, age at first and second operation, time to failure of first operation, etiology of hydrocephalus, prior CPC, and mode of ETV obstruction (simple stoma closure, second membrane, or cisternal obstruction from arachnoid scarring) were assessed using the Kaplan-Meier survival method. Survival differences among groups were assessed using log-rank and Wilcoxon methods and a Cox proportional hazards model.

RESULTS

There were 125 boys and 90 girls with mean and median ages of 229 and 92 days, respectively, at the initial ETV. Mean and median ages at repeat ETV were 347 and 180 days, respectively. Postinfectious hydrocephalus (PIH) was the etiology in 126 patients, and nonpostinfectious hydrocephalus (NPIH) in 89. Overall estimated 7-year success for repeat ETV was 51%. Sex (p = 0.46, log-rank test; p = 0.54, Wilcoxon test), age (< vs > 6 months) at initial or repeat ETV (p = 0.08 initial, p = 0.13 repeat; log-rank test), and type of ETV obstruction (p = 0.61, log-rank test) did not affect outcome for repeat ETV (p values ≥ 0.05, Cox regression). Those with a longer time to failure of initial ETV (> 6 months 91%, 3–6 months 60%, < 3 months 42%, p < 0.01; log-rank test), postinfectious etiology (PIH 58% vs NPIH 42%, p = 0.02; log-rank and Wilcoxon tests) and prior CPC (p = 0.03, log-rank and Wilcoxon tests) had significantly better outcome.

CONCLUSIONS

Repeat ETV was successful in half of the patients overall, and was more successful in association with later failures, prior CPC, and PIH. Obstruction of the original ETV by secondary arachnoid scarring was not a negative prognostic factor, and should not discourage the surgeon from proceeding. Repeat ETV may be a more durable solution to failed ETV/CPC than shunt placement in this context, especially for failures at more than 3 months after the initial ETV. Some ETV closures may result from an inflammatory response that is less robust at the second operation.