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Edward S. Ahn and Liliana Goumnerova

Object

Endoscopic biopsy is an important minimally invasive method of diagnosis in the initial management of lesions in children with intraventricular and periventricular tumors. The procedure can be performed in conjunction with CSF-diverting procedures for obstructive hydrocephalus. The authors present their single-institution experience in a predominantly pediatric series with respect to diagnostic efficacy, utility in guiding treatment plans, and safety.

Methods

A retrospective review was conducted in a consecutive series of patients who underwent endoscopic biopsy of brain tumors during a 13-year period.

Results

There were 33 endoscopic biopsies in 31 patients (16 males and 15 females). The average age of the patients was 11.3 years, with a mean follow-up duration of 2.4 years. The majority of biopsies were performed in conjunction with CSF-diverting procedures, such as endoscopic third ventriculostomy or fenestration of the septum pellucidum. Overall, 23 (70%) of 33 biopsies were diagnostic, with results that directed subsequent treatment. When stratified by tumor location, biopsy samples obtained in the lateral ventricle or pineal region were more favorable toward a successful diagnosis than those in the thalamus or tectal region. In 4 cases, elevated CSF tumor marker levels led to modification of the diagnosis and appropriate adjustment of treatment. The endoscopic third ventriculostomy success rate was 82.4%. There were 2 major complications (6.1%), which resulted in neurological deficits. There were no procedure-related deaths.

Conclusions

Endoscopic biopsy is an effective means of diagnosis of brain tumors in children. The diagnostic power may be more favorable with tumors in the lateral ventricle or pineal region. Collection of CSF during the procedure for tumor marker analysis is an integral component of diagnosis.

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Edward S. Ahn and Edward R. Smith

✓Infratentorial and spinal subdural hematomas (SDHs) from traumatic injury in the pediatric population occur with such rarity that they can present the clinician with a challenge in diagnosis and management. When such hematomas are correctly identified, clinicians must decide whether to evacuate the lesion or manage it expectantly. The authors discuss the case of a 4-year-old child who presented with a clival and spinal SDH after a fall from a fourth-story window. The clinical and radiographic findings support a possible mechanism of evolution of these lesions. There is little evidence to guide management of clival and spinal SDHs. This case supports the evaluation for a spinal SDH when a clival hematoma is diagnosed. In the setting of a good neurological examination, expectant management can be an appropriate method of treatment. Additionally, this case lends insight into the pathophysiology of spinal SDHs. Unlike its intracranial counterpart, the spinal subdural space lacks bridging veins. The mechanism of formation of spinal SDHs after trauma has been heretofore relatively unclear. The images in this case support the hypothesis that redistribution of the clival SDH to dependent areas in the spinal subdural space is a significant mechanism in the evolution of these lesions.

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Vivek Mehta, Joshua Bakhsheshian, Amir H. Dorafshar and Edward S. Ahn

The authors describe the case of a boy with Muenke syndrome, an autosomal dominant disorder associated with craniosynostosis. The family history was significant for syndromic craniosynostosis in the patient’s maternal grandmother, who died in adulthood after a craniofacial reconstruction. The patient, her grandson, underwent craniofacial reconstruction surgery at the age of 9 months and developed upward transtentorial herniation. Imaging findings revealed remote cerebellar hemorrhage after a large quantity of supratentorial CSF was drained during postoperative Day 1. The clinical course was further complicated by cerebral sinus thrombosis, which was diagnosed after a fourth surgical procedure. Upward transtentorial herniation can occur when a significant increase in intracranial pressure in the posterior fossa causes displacement of the central lobule and superior surfaces of the cerebellum upward through the incisura tentorii. This is a rare but well-documented phenomenon that commonly occurs in the setting of an expansive posterior fossa lesion or excessive supratentorial CSF loss. To help clinicians recognize and prevent this rare but potentially fatal complication, the authors review the postulated mechanisms by which this process may occur.

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Courtney Pendleton, Edward S. Ahn and Alfredo Quiñones-Hinojosa

Object

Harvey Cushing, credited with pioneering the field of neurosurgery as a distinct surgical subspecialty in the US, was at the forefront of neurooncology, publishing seminal papers on the diagnosis and treatment of pediatric brain tumors during the latter part of his career. However, his contributions to the surgical treatment of these lesions during the early stages of his tenure at the Johns Hopkins Hospital, from 1896 to 1912, remain largely unknown.

Methods

After obtaining institutional review board approval, and through the courtesy of the Alan Mason Chesney Archives, the authors reviewed the Johns Hopkins Hospital surgical files from the years 1896 to 1912. Patients younger than 18 years of age, presenting with symptoms suspicious for an intracranial tumor, and undergoing surgical intervention by Cushing were selected for further analysis.

Results

Of the 40 pediatric patients undergoing surgery for suspected intracranial neoplasms, 26 were male. The mean age among the entire sample was 10.1 years. Cushing used three main operative approaches in the surgical treatment of pediatric intracranial neoplasms: infratentorial/suboccipital, subtemporal, and hemisphere flap. Twenty-three patients had negative findings following both the primary and subsequent surgical interventions conducted by Cushing. Postoperative conditions following the primary surgical intervention were improved in 24 patients. Twelve patients (30%) died during their inpatient stay for the primary intervention. The mean time to the last follow-up was 24.9 months; the mean time to death was 10.0 months.

Conclusions

Cushing strove to maximize exposure while minimizing blood loss in an attempt to increase his ability to successfully treat pediatric brain tumors. His early contributions to the field of pediatric neurooncology demonstrate his commitment to advancing the field of neurosurgery.

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Jonathan Pindrik, George I. Jallo and Edward S. Ahn

This case series highlights multiple complications and subsequent removal of retained shunt hardware in pediatric patients after successful endoscopic third ventriculostomy (ETV). Removal or retention of existing shunt hardware following ETV represents an important dilemma. Prior studies have reported infections and organ perforation related to nonfunctioning shunts but none in the context of successful ETV. Data obtained in 3 children with hydrocephalus treated at the authors' institution were retrospectively reviewed after the patients experienced complications due to retained shunt hardware following ETV. Etiologies of hydrocephalus included tectal glioma and intraventricular hemorrhage. All 3 patients had a history of multiple shunt revisions and underwent urgent ETV in the setting of a shunt malfunction. In each case, the entire shunt system was left in situ, but it became the source of subsequent complications. Two of the 3 patients presented with the shunt infected by gram-negative bacilli 10 days and 4.5 months postoperatively, respectively. The remaining patient experienced wound dehiscence over the shunt valve 4.5 months after ETV. In all patients, the complications were managed successfully by removing the shunt hardware. None of the patients required repeat shunt insertion from the time of removal throughout the follow-up period (mean 24 months, range 9–36 months). During the study period, a total of 6 patients with indwelling shunt hardware underwent ETV with the expectation of being shunt independent. Among these 6 patients, 3 experienced no complications from the retained hardware whereas 3 patients (50%) ultimately experienced adverse consequences related to retained hardware. This case series illustrates complications involving retained shunt hardware after successful ETV. These examples support consideration of shunt removal at the time of ETV in the appropriate context.

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James L. Frazier, Edward S. Ahn and George I. Jallo

✓ Brain abscesses occur infrequently but continue to be problematic for the pediatric neurosurgical community. The incidence of brain abscesses in children has not changed much, although individual reports may show an increase or decrease in the number of reported cases depending on the patient population studied. An increase could be attributed to earlier detection due to advancements in imaging modalities and/or to an increase in the number of children with immunodeficient states caused by AIDS, chemotherapy for malignant lesions, and immunosuppressive therapy for organ transplantation. A decrease in the incidence of brain abscesses could be attributed to practices such as antibiotic treatment for otitis media, sinusitis, and/or prophylactic antimicrobial treatment for congenital heart disease in children. The morbidity and mortality rates associated with brain abscesses have not changed dramatically in the antibiotic and imaging era, and their preferred management can vary among healthcare providers. These lesions have been successfully treated by neurosurgeons. The causes of brain abscesses are highly variable in children, which is also the case in adults, but the predisposing factors in the pediatric population differ in prevalence. Cyanotic congenital heart disease, hematogenous dissemination, contiguous infection, and penetrating traumatic injuries are the most common causes of brain abscesses in children. In this review, the authors discuss the causes and medical and surgical management of brain abscesses in children.

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Edward S. Ahn, R. Michael Scott, Richard L. Robertson Jr. and Edward R. Smith

Object

Chorea is a movement disorder characterized by brief, irregular, involuntary contractions that appear to flow from 1 muscle to another. There are a limited number of reports in the literature that have linked moyamoya disease and chorea. The authors describe their experience in treating moyamoya disease in patients in whom chorea developed as part of the clinical presentation.

Methods

The authors conducted a retrospective review of a consecutive series of 316 children who underwent pial synangiosis revascularization for moyamoya disease at the Boston Children's Hospital.

Results

Of 316 surgically treated patients with moyamoya disease, 10 (3.2%; 6 boys and 4 girls) had chorea as a part of their presentation. The average age at surgical treatment was 9.9 years (range 3.8–17.9 years). All patients had evidence of hypertrophied lenticulostriate collateral vessels through the basal ganglia on preoperative angiography and/or MRI on affected sides. Two patients had cystic lesions in the basal ganglia. Nine patients underwent bilateral craniotomies for pial synangiosis, and 1 patient underwent a single craniotomy for unilateral disease. Follow-up was available in 9 patients (average 50.1 months). The mean duration of chorea was 1.36 years (range 2 days to 4 years), with resolution of symptoms in all patients. One patient developed chorea 3 years after surgical treatment, 4 patients had transient chorea that resolved prior to surgery, and 5 patients experienced resolution of the chorea after surgery (average 13 months).

Conclusions

The authors describe children with moyamoya disease and chorea as part of their clinical presentation. The data suggest that involvement of the basal ganglia by the hypertrophied collateral vessels contributes to the development of chorea, which can wax or wane depending on disease stage or involution of the vessels after revascularization surgery. In most patients, however, the chorea improves or disappears about 1 year after presentation.

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David S. Hersh, Julie E. Hoover-Fong, Natalie Beck, Amir H. Dorafshar and Edward S. Ahn

OBJECTIVE

Recent reports have described early endoscopic suturectomy as a treatment option for patients with syndromic craniosynostosis, but such patients often require subsequent calvarial remodeling. The authors describe their experience with this patient population and seek to identify predictors of sufficiency of endoscopic surgery alone.

METHODS

The medical records of patients with syndromic craniosynostosis who underwent endoscopic repair were retrospectively reviewed. Demographic data, operative details, and follow-up data were collected.

RESULTS

A total of 6 patients with syndromic craniosynostosis underwent endoscopic surgery followed by helmet therapy during the study period. Of these, 3 patients were male. The involved syndromes included Crouzon, Pfeiffer, Jackson-Weiss, Muenke, Saethre-Chotzen, and craniosynostosis-3 (n = 1 each). The patients underwent endoscopic surgery at a median age of 2.1 months (range 0.9–4.1 months). The median estimated blood loss was 30 ml (range 20–100 ml), with 2 patients requiring a transfusion. The median length of stay in the hospital was 1.5 days (range 1–4 days), and the median follow-up was 29.0 months (range 16.8–81.7 months), with 1 patient (16.7%) requiring an open revision. Three patients (50%) were classified as Whitaker Category I at the last follow-up. The patients for whom additional open surgery was performed or recommended (Whitaker Category IV) were the oldest patients in the cohort, ranging from 2.6 to 4.1 months at the time of surgery.

CONCLUSIONS

This series demonstrates that endoscopic surgery can be sufficient to treat syndromic craniosynostosis without subsequent open calvarial remodeling over a median follow-up period of at least 2 years. The findings suggest that younger age at the time of endoscopic surgery may be an important factor in determining the sufficiency of this procedure. Even among patients who require subsequent open calvarial remodeling, early endoscopic surgery may allow for growth and development of the brain and skull while delaying the need for open remodeling until the patient is older and can better tolerate the procedure.

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Jonathan Pindrik, Joseph Molenda, Rafael Uribe-Cardenas, Amir H. Dorafshar and Edward S. Ahn

OBJECTIVE

Subjective evaluations typically guide craniosynostosis repair. This study provides normative values of anthropometric cranial indices that are clinically useful for the evaluation of multiple types of craniosynostosis and introduces 2 new indices that are useful in the evaluation and management of metopic and bicoronal synostosis. The authors hypothesize that normative values of the new indices as well as for established measures like the cephalic index can be drawn from the evaluation of CT scans of normal individuals.

METHODS

High-resolution 3D CT scans obtained in normal infants (age 0–24 months) were retrospectively reviewed. Calvarial measurements obtained from advanced imaging visualization software were used to compute cranial indices. Additionally, metopic sutures were evaluated for patency or closure.

RESULTS

A total of 312 participants were included in the study. Each monthly age group (total 24) included 12–18 patients, yielding 324 head CT scans studied. The mean cephalic index decreased from 0.85 at age 0–3 months to 0.81 at 19–24 months, the mean frontoparietal index decreased from 0.68 to 0.65, the metopic index from 0.59 to 0.55, and the towering index remained comparatively uniform at 0.64 and 0.65. Trends were statistically significant for all measured indices. There were no significant differences found in mean cranial indices between sexes in any age group. Metopic suture closure frequency for ages 3, 6, and 9 months were 38.5%, 69.2%, and 100.0%, respectively.

CONCLUSIONS

Radiographically acquired normative values for anthropometric cranial indices during infancy can be used as standards for guiding preoperative decision making, surgical correction, and postoperative helmeting in various forms of craniosynostosis. Metopic and towering indices represent new cranial indices that are potentially useful for the clinical evaluation of metopic and bicoronal synostoses, respectively. The present study additionally shows that metopic suture closure appears ubiquitous after 9 months of age.

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Joanna Y. Wang, Amir H. Dorafshar, Ann Liu, Mari L. Groves and Edward S. Ahn

OBJECTIVE

Because the metopic suture normally fuses during infancy, there are varying degrees of severity in head shape abnormalities associated with premature fusion. A method for the objective and reproducible assessment of metopic synostosis is needed to guide management, as current methods are limited by their reliance on aesthetic markers. The object of this study was to describe the metopic index (MI), a simple anthropometric cranial measurement. The measurements can be obtained from CT scans and, more importantly, from palpable cranial landmarks, and the index provides a rapid tool for evaluating patients in both pre- and postoperative settings.

METHODS

High-resolution head CT scans obtained in 69 patients (age range 0–24 months) diagnosed with metopic craniosynostosis were retrospectively reviewed. Preoperative 3D reconstructions were available in 15 cases, and these were compared with 3D reconstructions of 324 CT scans obtained in a control group of 316 infants (age range 0–24 months) who did not have any condition that might affect head size or shape and also in a subset of this group, comprising 112 patients precisely matched to the craniosynostosis patients with respect to age and sex. Postoperative scans were available and reviewed in 9 of the craniosynostosis patients at a mean time of 7.1 months after surgical repair. 3D reconstructions of these scans were matched with controls based upon age and sex.

RESULTS

The mean preoperative MI for patients with trigonocephaly was 0.48 (SD 0.05), significantly lower than the mean values of 0.57 (SD 0.04) calculated on the basis of all 324 scans obtained in controls (p < 0.001) and 0.58 (SD 0.04) for the subset of 112 age- and sex-matched controls (p < 0.001). For 7 patients with both pre- and postoperative CT scans available for evaluation, the mean postoperative MI was 0.55 (SD 0.03), significantly greater than their preoperative MIs (mean 0.48 [SD 0.04], p = 0.001) and comparable to the mean MI of the controls (p = 0.30). In 4 patients, clinically obtained postoperative MIs by caliper measurement were comparable to measurements derived from CT (p = 0.141).

CONCLUSIONS

The MI is a useful measurement of the severity of trigonocephaly in patients with metopic synostosis. This simple quantitative assessment can potentially be used in the clinical setting to guide preoperative evaluation, surgical repair, and postoperative degree of correction.