Search Results

You are looking at 11 - 20 of 26 items for

  • Author or Editor: Christopher M. Bonfield x
Clear All Modify Search
Restricted access

Robert Kellogg, Philip Lee, Christopher P. Deibert, Zachary Tempel, Nathan T. Zwagerman, Christopher M. Bonfield, Stephen Johnson and Stephanie Greene

OBJECTIVE

The authors reviewed 20 years’ experience with the surgical management of open myelomeningocele in a well-defined retrospective cohort from a single large academic medical center. Their goal was to define the characteristics of a modern cohort of children with myelomeningocele to allow for evidence-based decision-making for the treatment of these patients.

METHODS

After IRB approval was obtained, the authors queried an operative database maintained by the Department of Neurological Surgery at Children’s Hospital of Pittsburgh for patients who underwent closure of a myelomeningocele between 1995 and 2015. They identified 153 infants, and a retrospective chart review was performed.

RESULTS

Eighty-eight percent of the patients required placement of a ventriculoperitoneal shunt, and 15% of these patients acquired shunt-related infections. Eighteen percent of patients underwent Chiari malformation type II (CM-II) decompression. Sixteen percent of patients underwent a tethered cord release. Three percent of patients died within the 1st year of life. Predictors of an early demise included poor Apgar scores, large head circumference, and need for early CM-II decompression. Functional motor outcome was slightly better than predicted by anatomical level of defect.

CONCLUSIONS

Myelomeningoceles represent a severe birth defect with life-threatening complications. The authors provide long-term follow-up data and insight into factors that contribute to early death.

Free access

Scott L. Zuckerman, Colin T. Prather, Aaron M. Yengo-Kahn, Gary S. Solomon, Allen K. Sills and Christopher M. Bonfield

OBJECTIVE

Arachnoid cysts (ACs) are congenital lesions bordered by an arachnoid membrane. Researchers have postulated that individuals with an AC demonstrate a higher rate of structural brain injury after trauma. Given the potential neurological consequences of a structural brain injury requiring neurosurgical intervention, the authors sought to perform a systematic review of sport-related structural-brain injury associated with ACs with a corresponding quantitative analysis.

METHODS

Titles and abstracts were searched systematically across the following databases: PubMed, Embase, CINAHL, and PsycINFO. The review was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) statement. Peer-reviewed case reports, case series, or observational studies that reported a structural brain injury due to a sport or recreational activity (hereafter referred to as sport-related) with an associated AC were included. Patients were excluded if they did not have an AC, suffered a concussion without structural brain injury, or sustained the injury during a non–sport-related activity (e.g., fall, motor vehicle collision). Descriptive statistical analysis and time to presentation data were summarized. Univariate logistic regression models to assess predictors of neurological deficit, open craniotomy, and cystoperitoneal shunt were completed.

RESULTS

After an initial search of 994 original articles, 52 studies were found that reported 65 cases of sport-related structural brain injury associated with an AC. The median age at presentation was 16 years (range 4–75 years). Headache was the most common presenting symptom (98%), followed by nausea and vomiting in 49%. Thirteen patients (21%) presented with a neurological deficit, most commonly hemiparesis. Open craniotomy was the most common form of treatment (49%). Bur holes and cyst fenestration were performed in 29 (45%) and 31 (48%) patients, respectively. Seven patients (11%) received a cystoperitoneal shunt. Four cases reported medical management only without any surgical intervention. No significant predictors were found for neurological deficit or open craniotomy. In the univariate model predicting the need for a cystoperitoneal shunt, the odds of receiving a shunt decreased as age increased (p = 0.004, OR 0.62 [95% CI 0.45–0.86]) and with male sex (p = 0.036, OR 0.15 [95% CI 0.03–0.88]).

CONCLUSIONS

This systematic review yielded 65 cases of sport-related structural brain injury associated with ACs. The majority of patients presented with chronic symptoms, and recovery was reported generally to be good. Although the review is subject to publication bias, the authors do not find at present that there is contraindication for patients with an AC to participate in sports, although parents and children should be counseled appropriately. Further studies are necessary to better evaluate AC characteristics that could pose a higher risk of adverse events after trauma.

Full access

Matthew B. Maserati, Matthew J. Tormenti, David M. Panczykowski, Christopher M. Bonfield and Peter C. Gerszten

Object

The authors report the use and preliminary results of a novel hybrid dynamic stabilization and fusion construct for the surgical treatment of degenerative lumbar spine pathology.

Methods

The authors performed a retrospective chart review of all patients who underwent posterior lumbar instrumentation with the Dynesys-to-Optima (DTO) hybrid dynamic stabilization and fusion system. Preoperative symptoms, visual analog scale (VAS) pain scores, perioperative complications, and the need for subsequent revision surgery were recorded. Each patient was then contacted via telephone to determine current symptoms and VAS score. Follow-up was available for 22 of 24 patients, and the follow-up period ranged from 1 to 22 months. Clinical outcome was gauged by comparing VAS scores prior to surgery and at the time of telephone interview.

Results

A total of 24 consecutive patients underwent lumbar arthrodesis surgery in which the hybrid system was used for adjacent-level dynamic stabilization. The mean preoperative VAS score was 8.8, whereas the mean postoperative VAS score was 5.3. There were five perioperative complications that included 2 durotomies and 2 wound infections. In addition, 1 patient had a symptomatic medially placed pedicle screw that required revision. These complications were not thought to be specific to the DTO system itself. In 3 patients treatment failed, with treatment failure being defined as persistent preoperative symptoms requiring reoperation.

Conclusions

The DTO system represents a novel hybrid dynamic stabilization and fusion construct. The technique holds promise as an alternative to multilevel lumbar arthrodesis while potentially decreasing the risk of adjacent-segment disease following lumbar arthrodesis. The technology is still in its infancy and therefore follow-up, when available, remains short. The authors report their preliminary experience using a hybrid system in 24 patients, along with short-interval clinical and radiographic follow-up.

Full access

Matthew J. Tormenti, Matthew B. Maserati, Christopher M. Bonfield, David O. Okonkwo and Adam S. Kanter

Object

The authors recently used a combined approach of minimally invasive transpsoas extreme lateral interbody fusion (XLIF) and open posterior segmental pedicle screw instrumentation with transforaminal lumbar interbody fusion (TLIF) for the correction of coronal deformity. The complications and radiographic outcomes were compared with a posterior-only approach for scoliosis correction.

Methods

The authors retrospectively reviewed all deformity cases that were surgically corrected at the University of Pittsburgh Medical Center Presbyterian Hospital between June 2007 and August 2009. Eight patients underwent combined transpsoas and posterior approaches for adult degenerative thoracolumbar scoliosis. The comparison group consisted of 4 adult patients who underwent a posterior-only scoliosis correction. Data on intra- and postoperative complications were collected. The pre- and postoperative posterior-anterior and lateral scoliosis series radiographic films were reviewed, and comparisons were made for coronal deformity, apical vertebral translation (AVT), and lumbar lordosis. Clinical outcomes were evaluated by comparing pre- and postoperative visual analog scale scores.

Results

The median preoperative coronal Cobb angle in the combined approach was 38.5° (range 18–80°). Following surgery, the median Cobb angle was 10° (p < 0.0001). The mean preoperative AVT was 3.6 cm, improving to 1.8 cm postoperatively (p = 0.031). The mean preoperative lumbar lordosis in this group was 47.3°, and the mean postoperative lordosis was 40.4°. Compared with posterior-only deformity corrections, the mean values for curve correction were higher for the combined approach than for the posterior-only approach. Conversely, the mean AVT correction was higher in the posterior-only group. One patient in the posterior-only group required revision of the instrumentation. One patient who underwent the transpsoas XLIF approach suffered an intraoperative bowel injury necessitating laparotomy and segmental bowel resection; this patient later underwent an uneventful posterior-only correction of her scoliotic deformity. Two patients (25%) in the XLIF group sustained motor radiculopathies, and 6 of 8 patients (75%) experienced postoperative thigh paresthesias or dysesthesias. Motor radiculopathy resolved in 1 patient, but persisted 3 months postsurgery in the other. Sensory symptoms persisted in 5 of 6 patients at the most recent follow-up evaluation. The mean clinical follow-up time was 10.5 months for the XLIF group and 11.5 months for the posterior-only group. The mean visual analog scale score decreased from 8.8 to 3.5 in the XLIF group, and it decreased from 9.5 to 4 in the posterior-only group.

Conclusions

Radiographic outcomes such as the Cobb angle and AVT were significantly improved in patients who underwent a combined transpsoas and posterior approach. Lumbar lordosis was maintained in all patients undergoing the combined approach. The combination of XLIF and TLIF/posterior segmental instrumentation techniques may lead to less blood loss and to radiographic outcomes that are comparable to traditional posterior-only approaches. However, the surgical technique carries significant risks that require further evaluation and proper informed consent.

Full access

Zackary D. Brown, Amita K. Bey, Christopher M. Bonfield, Ashly C. Westrick, Katherine Kelly, Kevin Kelly and John C. Wellons III

OBJECTIVE

Disparities in surgical access and timing to care result from a combination of complex patient, social, and institutional factors. Due to the perception of delayed presentation for overall health care services and treatment in African American patients on the part of the senior author, this study was designed to identify and quantify these differences in access and care between African American and Caucasian children with craniosynostosis. In addition, hypotheses regarding reasons for this difference are discussed.

METHODS

A retrospective study was conducted of 132 children between the ages of 0 and 17 years old who previously underwent operations for craniosynostosis at a tertiary pediatric care facility between 2010 and 2013. Patient and family characteristics, age at surgical consultation and time to surgery, and distance to primary care providers and the tertiary center were recorded and analyzed.

RESULTS

Of the 132 patients in this cohort, 88% were Caucasian and 12% were African American. The median patient age was 5 months (interquartile range [IQR] 2–8 months). African Americans had a significantly greater age at consult compared with Caucasians (median 341 days [IQR 192–584 days] vs median 137 days [IQR 62–235 days], respectively; p = 0.0012). However, after being evaluated in consultation, there was no significant difference in time to surgery between African American and Caucasian patients (median 56 days [IQR 36–98 days] vs median 64 days [IQR 43–87 days], respectively). Using regression analysis, race and type of synostoses were found to be significantly associated with a longer wait time for surgical consultation (p = 0.01 and p = 0.04, respectively, using cutoff points of ≤ 180 days vs > 180 days). Distance traveled to primary care physicians and to the tertiary care facility did not significantly differ between groups. Other factors such as parental education, insurance type, household income, and referring physician type also showed no significant difference between racial groups.

CONCLUSIONS

This study identified a correlation between race and age at consultation, but no association with time to surgery, distance, or family characteristics such as household income, parental education, insurance type, and referring physician type. This finding implies that delays in early health-seeking behaviors and subsequent referral to surgical specialists from primary care providers are the main reason for this delay among African American craniofacial patients. Future studies should focus on further detail in regards to these barriers, and educational efforts should be designed for the community and the health care personnel caring for them.

Restricted access

Christopher M. Bonfield, Jade Basem, D. Douglas Cochrane, Ash Singhal and Paul Steinbok

OBJECTIVE

At British Columbia Children’s Hospital (BCCH), pediatric patients with nonsyndromic craniosynostosis are admitted directly to a standard surgical ward after craniosynostosis surgery. This study’s purpose was to investigate the safety of direct ward admission and to examine the rate at which patients were transferred to the intensive care unit (ICU), the cause for the transfer, and any patient characteristics that indicate higher risk for ICU care.

METHODS

The authors retrospectively reviewed medical records of pediatric patients who underwent single-suture or nonsyndromic craniosynostosis repair from 2011 to 2016 at BCCH. Destination of admission from the operating room (i.e., ward or ICU) and transfer to the ICU from the ward were evaluated. Patient characteristics and operative factors were recorded and analyzed.

RESULTS

One hundred fourteen patients underwent surgery for single-suture or nonsyndromic craniosynostosis. Eighty surgeries were open procedures (cranial vault reconstruction, frontoorbital advancement, extended-strip craniectomy) and 34 were minimally invasive endoscope-assisted craniectomy (EAC). Sutures affected were sagittal in 66 cases (32 open, 34 EAC), coronal in 20 (15 unilateral, 5 bilateral), metopic in 23, and multisuture in 5. Only 5 patients who underwent open procedures (6%) were initially admitted to the ICU from the operating room; the reasons for direct admission were as follows: the suggestion of preoperative elevated intracranial pressure, pain control, older-age patients with large reconstruction sites, or a significant medical comorbidity. Overall, of the 107 patients admitted directly to the ward (75 who underwent an open surgery, 32 who underwent an EAC), none required ICU transfer.

CONCLUSIONS

Overall, the findings of this study suggest that patients with nonsyndromic craniosynostosis can be managed safely on the ward and do not require postoperative ICU admission. This could potentially increase cost savings and ICU resource utilization.

Free access

Emily W. Chan, Stephen R. Gannon, Chevis N. Shannon, Jeffrey E. Martus, Gregory A. Mencio and Christopher M. Bonfield

OBJECTIVE

Adolescent idiopathic scoliosis (AIS), the most common type of scoliosis, often presents immediately prior to a woman’s childbearing years; however, research investigating the impact of AIS on women’s health, particularly pregnancy delivery outcomes, is sparse, with existing literature reporting mixed findings. Similarly limited are studies examining the change in scoliotic curve during or after pregnancy. Therefore, this study aims to determine 1) the impact of scoliotic curvature on obstetric complications (preterm births, induction of labor, and urgent/emergency caesarean section delivery), 2) regional anesthetic decision making and success during delivery for these patients, and 3) the effect of pregnancy on curve progression.

METHODS

Records of all pregnant patients diagnosed with AIS at the authors’ institution who delivered between January 2002 and September 2016 were retrospectively reviewed. Demographic information, pre- and postpartum radiographic Cobb angles, and clinical data for each pregnancy and delivery were recorded and analyzed. The Wilcoxon rank-sum test and the Wilcoxon signed-rank test were used for statistical analyses.

RESULTS

Fifty-nine patients (84 deliveries) were included; 14 patients had undergone prior posterior spinal fusion. The median age at AIS diagnosis was 15.2 years, and the median age at delivery was 21.8 years. Overall, the median major Cobb angle prior to the first pregnancy was 25° (IQR 15°–40°). Most births were by spontaneous vaginal delivery (n = 45; 54%); elective caesarean section was performed in 17 deliveries (20%). Obstetric complications included preterm birth (n = 18; 21.4%), induction of labor (n = 20; 23.8%), and urgent/emergency caesarean section (n = 12; 14.0%); none were associated with severity of scoliosis curve or prior spinal fusion. Attempts at spinal anesthesia were successful 99% of the time (70/71 deliveries), even among the patients who had undergone prior spinal fusion (n = 13). There were only 3 instances of provider refusal to administer spinal anesthesia. In the subset of 11 patients who underwent postpartum scoliosis radiography, there was no statistically significant change in curve magnitude either during or immediately after pregnancy.

CONCLUSIONS

The results of this study suggest that there was no effect of the severity of scoliosis on delivery complications or regional anesthetic decision making in pregnant patients with AIS. Moreover, scoliosis was not observed to progress significantly during or immediately after pregnancy. Larger prospective studies are needed to further investigate these outcomes, the findings of which can guide the prenatal education and counseling of pregnant patients with AIS.

Full access

Nishit Mummareddy, Michael C. Dewan, Michael R. Mercier, Robert P. Naftel, John C. Wellons III and Christopher M. Bonfield

OBJECTIVE

The authors aimed to provide an updated and consolidated report on the epidemiology, management, and functional outcome of cases of myelomeningocele (MMC) in patients with scoliosis.

METHODS

A comprehensive literature search was performed using MEDLINE, Embase, Google Scholar, and the Cochrane Database of Systematic Reviews on cases of MMC in patients with scoliosis between 1980 and 2016. The initial search yielded 670 reports. After removing duplicates and applying inclusion criteria, we included 32 full-text original articles in this study.

RESULTS

Pooled statistical analysis of the included articles revealed the prevalence of scoliosis in MMC patients to be 53% (95% CI 0.42–0.64). Slightly more females (56%) are affected with both MMC and scoliosis than males. Motor level appears to be a significant predictor of prevalence, but not severity, of scoliosis in MMC patients. Treatment options for these patients include tethered cord release (TCR) and fusion surgeries. Curvature improvement and stabilization after TCR may be limited to patients with milder (< 50°) curves. Meanwhile, more aggressive fusion procedures such as a combined anterior-posterior approach may result in more favorable long-term scoliosis correction, albeit with greater complication rates. Quality of life metrics including ambulatory status and sitting stability are influenced by motor level of the lesion as well as the degree of the scoliosis curvature.

CONCLUSIONS

Scoliosis is among the most common and challenging comorbidities from which patients with MMC suffer. Although important epidemiological and management trends are evident, larger, prospective studies are needed to discover ways to more accurately counsel and more optimally treat these patients.

Restricted access

Christopher M. Bonfield, Rachel Pellegrino, Jillian Berkman, Robert P. Naftel, Chevis N. Shannon and John C. Wellons III

OBJECTIVE

Both the American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Section on Pediatric Neurological Surgery (AANS/CNS Pediatric Section) and the International Society for Pediatric Neurosurgery (ISPN) annual meetings provide a platform for pediatric neurosurgeons to present, discuss, and disseminate current academic research. An ultimate goal of these meetings is to publish presented results in peer-reviewed journals. The purpose of the present study was to investigate the publication rates of oral presentations from the 2009, 2010, and 2011 AANS/CNS Pediatric Section and ISPN annual meetings in peer-reviewed journals.

METHODS

All oral presentations from the 2009, 2010, and 2011 AANS/CNS Pediatric Section and ISPN annual meetings were reviewed. Abstracts were obtained from the AANS/CNS Pediatric Section and ISPN conference proceedings, which are available online. Author and title information were used to search PubMed to identify those abstracts that had progressed to publication in peer-reviewed journals. The title of the journal, year of the publication, and authors’ country of origin were also recorded.

RESULTS

Overall, 60.6% of the presented oral abstracts from the AANS/CNS Pediatric Section meetings progressed to publication in peer-reviewed journals, as compared with 40.6% of the ISPN presented abstracts (p = 0.0001). The journals in which the AANS/CNS Pediatric Section abstract-based publications most commonly appeared were Journal of Neurosurgery: Pediatrics (52%), Child’s Nervous System (11%), and Journal of Neurosurgery (8%). The ISPN abstracts most often appeared in the journals Child’s Nervous System (29%), Journal of Neurosurgery: Pediatrics (14%), and Neurosurgery (9%). Overall, more than 90% of the abstract-based articles were published within 4 years after presentation of the abstracts on which they were based.

CONCLUSIONS

Oral abstract presentations at two annual pediatric neurosurgery meetings have publication rates in peer-reviewed journal comparable to those for oral abstracts at other national and international neurosurgery meetings. The vast majority of abstract-based papers are published within 4 years of the meeting at which the abstract was presented; however, the AANS/CNS Pediatric Section abstracts are published at a significantly higher rate than ISPN abstracts, which could indicate the different meeting sizes, research goals, and resources of US authors compared with those of authors from other countries.

Free access

Christopher M. Bonfield, Lesley M. Foley, Shinjini Kundu, Wendy Fellows-Mayle, T. Kevin Hitchens, Gustavo K. Rohde, Ramesh Grandhi and Mark P. Mooney

OBJECT

Craniosynostosis is a condition in which one or more of the calvarial sutures fuses prematurely. In addition to the cosmetic ramifications attributable to premature suture fusion, aberrations in neurophysiological parameters are seen, which may result in more significant damage. This work examines the microstructural integrity of white matter, using diffusion tensor imaging (DTI) in a homogeneous strain of rabbits with simple, familial coronal suture synostosis before and after surgical correction.

METHODS

After diagnosis, rabbits were assigned to different groups: wild-type (WT), rabbits with early-onset complete fusion of the coronal suture (BC), and rabbits that had undergone surgical correction with suturectomy (BC-SU) at 10 days of age. Fixed rabbit heads were imaged at 12, 25, or 42 days of life using a 4.7-T, 40-cm bore Avance scanner with a 7.2-cm radiofrequency coil. For DTI, a 3D spin echo sequence was used with a diffusion gradient (b = 2000 sec/mm2) applied in 6 directions.

RESULTS

As age increased from 12 to 42 days, the DTI differences between WT and BC groups became more pronounced (p < 0.05, 1-way ANOVA), especially in the corpus callosum, cingulum, and fimbriae. Suturectomy resulted in rabbits with no significant differences compared with WT animals, as assessed by DTI of white matter tracts. Also, it was possible to predict to which group an animal belonged (WT, BC, and BC-SU) with high accuracy based on imaging data alone using a linear support vector machine classifier. The ability to predict to which group the animal belonged improved as the age of the animal increased (71% accurate at 12 days and 100% accurate at 42 days).

CONCLUSIONS

Craniosynostosis results in characteristic changes of major white matter tracts, with differences becoming more apparent as the age of the rabbits increases. Early suturectomy (at 10 days of life) appears to mitigate these differences.