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Evelyne Emery, Philipp Aldana, Mary Bartlett Bunge, William Puckett, Anu Srinivasan, Robert W. Keane, John Bethea and Allan D. O. Levi

Object

Apoptosis is a form of programmed cell death seen in a variety of developmental and disease states, including traumatic injuries. The main objective of this study was to determine whether apoptosis is observed after human spinal cord injury (SCI). The spatial and temporal expression of apoptotic cells as well as the nature of the cells involved in programmed cell death were also investigated.

Methods

The authors examined the spinal cords of 15 patients who died between 3 hours and 2 months after a traumatic SCI. Apoptotic cells were found at the edges of the lesion epicenter and in the adjacent white matter, particularly in the ascending tracts, by using histological (cresyl violet, hematoxylin and eosin) and nuclear staining (Hoechst 33342). The suspected presence of apoptotic cells was supported by staining with the terminal deoxynucleotidyl transferase-mediated biotinylated-deoxyuridinetriphosphate nick-end labeling technique and confirmed by immunostaining for the processed form of caspase-3 (CPP-32), a member of the interleukin-1-beta-converting enzyme/Caenorhabditis elegans D 3 family of proteases that plays an essential role in programmed cell death. Apoptosis in this series of human SCIs was a prominent pathological finding in 14 of the 15 spinal cords examined when compared with five uninjured control spinal cords. To determine the type of cells undergoing apoptosis, the authors immunostained specimens with a variety of antibodies, including glial fibrillary acidic protein, 2,′3′-cyclic nucleotide 3′-phosphohydrolase (CNPase), and CD45/68. Oligodendrocytes stained with CNPase and a number of apoptotic nuclei colocalized with positive staining for this antibody.

Conclusions

These results support the hypothesis that apoptosis occurs in human SCIs and is accompanied by the activation of CPP-32 of the cysteine protease family. This mechanism of cell death contributes to the secondary injury processes seen after human SCI and may have important clinical implications for the further development of protease inhibitors to prevent programmed cell death.

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Evelyne Emery, Philipp Aldana, Mary Bartlett Bunge, William Puckett, Anu Srinivasan, Robert W. Keane, John Bethea and Allan D. O. Levi

Object. Apoptosis is a form of programmed cell death seen in a variety of developmental and disease states, including traumatic injuries. The main objective of this study was to determine whether apoptosis is observed after human spinal cord injury (SCI). The spatial and temporal expression of apoptotic cells as well as the nature of the cells involved in programmed cell death were also investigated.

Methods. The authors examined the spinal cords of 15 patients who died between 3 hours and 2 months after a traumatic SCI. Apoptotic cells were found at the edges of the lesion epicenter and in the adjacent white matter, particularly in the ascending tracts, by using histological (cresyl violet, hematoxylin and eosin) and nuclear staining (Hoechst 33342). The presence of apoptotic cells was supported by staining with the terminal deoxynucleotidyl transferase-mediated deoxyuridinetriphosphate nick-end labeling technique and confirmed by immunostaining for the processed form of caspase-3 (CPP-32), a member of the interleukin-1β-converting enzyme/Caenorhabditis elegans D 3 (ICE/CED-3) family of proteases that plays an essential role in programmed cell death. Apoptosis in this series of human SCIs was a prominent pathological finding in 14 of the 15 spinal cords examined when compared with five uninjured control spinal cords. To determine the type of cells undergoing apoptosis, the authors immunostained specimens with a variety of antibodies, including glial fibrillary acidic protein, 2′,3′-cyclic nucleotide 3′-phosphohydrolase (CNPase), and CD45/68. Oligodendrocytes stained with CNPase and a number of apoptotic nuclei colocalized with positive staining for this antibody.

Conclusions. These results support the hypothesis that apoptosis occurs in human SCIs and is accompanied by the activation of caspase-3 of the cysteine protease family. This mechanism of cell death contributes to the secondary injury processes seen after human SCI and may have important clinical implications for the further development of protease inhibitors to prevent programmed cell death.

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Philipp R. Aldana, Hector E. James and Richard A. Postlethwait

Object

The authors report a clinical protocol for the application of ventriculogallbladder (VGB) shunts in children who may be unable to maintain or receive ventriculoperitoneal (VP) shunts.

Methods

Eighteen patients underwent placement of VGB shunts as an alternative to VP shunt therapy for the following reasons: malfunction of the VP shunt due to suspected failure of the peritoneum to absorb cerebrospinal fluid (17 cases) and multiple intraabdominal general surgical procedures (1 case). The patients ranged in age from 4 months to 17 years (mean 6.5 ± 6.1 years [standard deviation {SD}]). All patients underwent preoperative imaging of the gall-bladder either by ultrasonography or computed tomography scanning. A team consisting of a pediatric neurological surgeon and a pediatric general surgeon performed all operative procedures. The procedures were conducted by open laparotomy to precisely place the appropriate length of distal catheter and to anchor it to the gallbladder wall.

Results

There were 2 early shunt malfunctions, both obstructions due to “sludge” (1 in the biliary duct and 1 in the common bile duct). A late-onset (5-year) malfunction occurred secondary to gallbladder stones. In all 3 cases of malfunction, the devices were successfully converted to VP shunts. In 1 patient a conversion to a VP shunt was chosen following a general surgical intervention. There were 2 shunt infections (Staphylococcus epidermidis and Haemophilus influenzae). These were successfully treated. Two patients underwent conversion to a VGB shunt on 2 occasions. Thirteen patients had functional VGB shunts at the time of their last follow-up assessment. The follow-up for these 13 patients ranged from 1 to 8 years (mean 2.1 ± 2.0 years [SD]).

Conclusions

Ventriculogallbladder shunts may be considered for the treatment of hydrocephalus in children when the peritoneal cavity cannot be used as a distal terminus.

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Philipp R. Aldana, Saswata Roy, Richard A. Postlethwait and Hector E. James

Object

Bioresorbable implant systems have been used in neurosurgery for the rigid fixation of cranial and facial bones. A relatively recent advancement has been the fixation of these implants using an ultrasonic device. The experience with such a device in neurosurgical practice has been limited. The authors report on their experience with ultrasound-aided fixation of bioresorbable implants in pediatric neurosurgical practice.

Methods

The study consisted of 2 parts. The retrospective portion consisted of a chart review of pertinent clinical information, complications, and outcomes after the use of a commercially available ultrasound-aided bioresorbable implant system (SonicWeld Rx, KLS Martin L.P.). Follow-up was obtained in all patients via clinical examination or telephone interview. The prospective portion of the study consisted of video analysis of the implantation technique in a routine craniotomy. Implantation times were measured, and delays during treatment were noted.

Results

Over a period of 2 years, 28 consecutive patients underwent placement of these implants for bone fixation during craniotomies or craniofacial reconstructions. The only complication was seen in a child with Crouzon syndrome, who had a wound infection caused by Serratia sepsis from a central venous line infection. There were no repeated operations for implant-related swelling, and no cases of premature plate resorption, bone instability, or settling. In vivo, the average time required to implant a resorbable pin with this system was 22 seconds.

Conclusions

The use of a bioresorbable implant system with ultrasound-aided pin fixation in pediatric neurosurgery cases achieved adequate stability with few complications. This system was easy to use and provided rapid fixation of implants.

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Editorial

Neurosurgical education for pediatricians

Joseph H. Piatt

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Philipp R. Aldana and Paul Steinbok

Object

Pediatricians play a vital role in the diagnosis and initial treatment of children with pediatric neurosurgical disease. Exposure of pediatrics residents to neurosurgical diseases during training is inconsistent and is usually quite limited. After residency, opportunities for pediatricians' education on neurosurgical topics are few and fall mainly on pediatric neurosurgeons. The American Association of Neurological Surgery/Congress of Neurological Surgeons Joint Section on Pediatric Neurological Surgery Committee on Education undertook a survey of practicing pediatric neurosurgeons to determine whether focused education of practicing pediatricians might lead to better patient outcomes for children with a sampling of common pediatric neurosurgical conditions.

Methods

An Internet-based 40-item survey was administered to practicing pediatric neurosurgeons from the US and Canada identified from the roster of the American Association of Neurological Surgeons/Congress of Neurological Surgeons Joint Section of Pediatric Neurological Surgery. Survey topics included craniosynostosis and plagiocephaly, occult spinal dysraphism and tethered cord, hydrocephalus and endoscopic third ventriculostomy, Chiari malformation Type I, mild or minor head injury, spastic cerebral palsy, and brain tumors. Most questions pertained to diagnosis, initial medical treatment, and referral.

Results

One hundred three (38%) of the 273 practicing pediatric neurosurgeons completed the survey. Two-thirds of the respondents had completed a pediatric neurosurgery fellowship, and two-thirds were in academic practice. Eighty-two percent of the respondents agreed that the care of pediatric neurosurgical patients could be improved with further education of pediatricians. In the opinion of the respondents, the 3 disease topics in greatest need of educational effort were craniosynostosis and plagiocephaly, occult spinal dysraphism and tethered cord, and hydrocephalus. Head injury and spasticity were given the lowest priorities.

Conclusions

This survey identified what practicing pediatric neurosurgeons perceive to be the most important knowledge deficits of their colleagues in pediatrics. These perceptions may not necessarily be congruent with the perceptions of practicing pediatricians themselves; nevertheless, the data from this survey may serve to inform conversations between neurosurgeons and planners of continuing medical education for pediatricians, pediatrics residency program directors, and medical school pediatrics faculty.

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Emanuele La Corte, Philipp R. Aldana, Paolo Ferroli, Jeffrey P. Greenfield, Roger Härtl, Vijay K. Anand and Theodore H. Schwartz

OBJECT

The endoscopic endonasal approach (EEA) provides a minimally invasive corridor through which the cervicomedullary junction can be decompressed with reduced morbidity rates compared to those with the classic transoral approaches. The limit of the EEA is its inferior extent, and preoperative estimation of its reach is vital for determining its suitability. The aim of this study was to evaluate the actual inferior limit of the EEA in a surgical series of patients and develop an accurate and reliable predictor that can be used in planning endonasal odontoidectomies.

METHODS

The actual inferior extent of surgery was determined in a series of 6 patients with adequate preoperative and postoperative imaging who underwent endoscopie endonasal odontoidectomy. The medians of the differences between several previously described predictive lines, namely the nasopalatine line (NPL) and nasoaxial line (NAxL), were compared with the actual surgical limit and the hard-palate line by using nonparametric statistics. A novel line, called the rhinopalatine line (RPL), was established and corresponded best with the actual limit of the surgery.

RESULTS

There were 4 adult and 2 pediatric patients included in this study. The NPL overestimated the inferior extent of the surgery by an average (± SD) of 21.9 ± 8.1 mm (range 14.7-32.5 mm). The NAxL and RPL overestimated the inferior limit of surgery by averages of 6.9 ± 3.8 mm (range 3.7-13.3 mm) and 1.7 ± 3.7 mm (range −2.8 to 8.3 mm), respectively. The medians of the differences between the NPL and NAxL and the actual surgery were statistically different (both p = 0.0313). In contrast, there was no statistically significant difference between the RPL and the inferior limit of surgery (p = 0.4375).

CONCLUSIONS

The RPL predicted the inferior limit of the EEA to the craniovertebral junction more accurately than previously described lines. The use of the RPL may help surgeons in choosing suitable candidates for the EEA and in selecting those for whom surgery through the oropharynx or the facial bones is the better approach.

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Hector E. James, Anthony A. Perszyk, Teresa L. MacGregor and Philipp R. Aldana

OBJECT

The cranium is documented to grow from birth through adolescence. The standard of practice in primary care is measuring head circumference and plotting growth using curves that stop at 36 months. The authors report the importance of their experience with measuring head circumference in the child and same-sex parent beyond 36 months.

METHODS

In the University of Florida genetics and pediatric neurosurgery clinics, head circumference is measured and plotted on growth charts through 18 years of age. Circumference and rate of growth over time are compared with those of the same-sex parent. A diagnostic workup is initiated if there is a discrepancy with the patient's head circumference or if there is significant change in the growth rate of the cranium.

RESULTS

Between January 2004 and December 2007, the lead author examined 190 patients referred by pediatricians and/or pediatric subspecialists because of the concerns regarding head size of the child. Neuroimaging was performed in 70% of the patients prior to referral. None of the patients had their head size compared with that of their same-sex parent prior to referral. On assessing referring physician responses as to why the same-sex parents, head measurements were not pursued prior to imaging or referral to the specialists, the results were: 1) only have head circumference sheets to 36 months of age (n = 28); 2) the American Academy of Pediatrics does not recommend it (n = 3); and 3) the head stops growing at 36 months of age (n = 2).

CONCLUSIONS

Pediatricians and pediatric subspecialists need instruction on head circumference measurement in children from infancy through adolescence, and when indicated, in comparison with the head size of the same-sex parent. This measurement may be an effective and inexpensive assessment tool.

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Amer Dastgir, Nathan J. Ranalli, Theresa L. MacGregor and Philipp R. Aldana

The authors report an unusual case of intrathecal baclofen withdrawal due to the perforation and subsequent leakage of a baclofen pump catheter in a patient with spastic cerebral palsy. A 15-year-old boy underwent an uncomplicated placement of an intrathecal baclofen pump for the treatment of spasticity due to cerebral palsy. After excellent control of symptoms for 3 years, the patient presented to the emergency department with increasing tremors following a refill of his baclofen pump. Initial evaluation consisted of radiographs of the pump and catheter, which appeared normal, and a successful aspiration of CSF from the pump’s side port. A CT dye study revealed a portion of the catheter directly overlying the refill port and extravasation of radiopaque dye into the subfascial pocket anterior to the pump. During subsequent revision surgery, a small puncture hole in the catheter was seen to be leaking the drug. The likely cause of the puncture was an inadvertent perforation of the catheter by a needle during the refilling of the pump. This case report highlights a unique complication in a patient with an intrathecal baclofen pump. Physicians caring for these patients should be aware of this rare yet potential complication in patients presenting with baclofen withdrawal symptoms.