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Edward S. Ahn, Lawrence S. Chin, Kymberly A. Gyure, Richard S. Hudes, John Ragheb and Arthur J. DiPatri Jr.

✓ Clear cell meningioma (CCM) is a rare variant of meningioma characterized by sheets of polygonal cells with clear cytoplasm, a feature attributable to its high glycogen content. Authors have described its propensity to recur and metastasize despite its benign pathological characteristics. Clinical response to radiation in these reports has varied.

The authors present the case of a 7-year-old girl with a large petroclival CCM who underwent a staged subtotal resection and subsequent gamma knife surgery (GKS). Initially, the residual tumor decreased in size, but 6 years later, it had regrown (9 mm in size). A second GKS treatment was performed and the mass completely regressed without further complication.

The findings in this case suggest that GKS is a safe and effective adjunct for residual and recurrent CCM after resection. The delayed recurrence also emphasizes the importance of undertaking close follow-up examination after treating this potentially aggressive variant of meningioma.

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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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M. Sean Grady

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Bizhan Aarabi, Dale C. Hesdorffer, Edward S. Ahn, Carla Aresco, Thomas M. Scalea and Howard M. Eisenberg

Object

The aim of this study was to assess outcome following decompressive craniectomy for malignant brain swelling due to closed traumatic brain injury (TBI).

Methods

During a 48-month period (March 2000–March 2004), 50 of 967 consecutive patients with closed TBI experienced diffuse brain swelling and underwent decompressive craniectomy, without removal of clots or contusion, to control intracranial pressure (ICP) or to reverse dangerous brain shifts. Diffuse injury was demonstrated in 44 patients, an evacuated mass lesion in four in whom decompressive craniectomy had been performed as a separate procedure, and a nonevacuated mass lesion in two. Decompressive craniectomy was performed urgently in 10 patients before ICP monitoring; in 40 patients the procedure was performed after ICP had become unresponsive to conventional medical management as outlined in the American Association of Neurological Surgeons guidelines. Survivors were followed up for at least 3 months posttreatment to determine their Glasgow Outcome Scale (GOS) score.

Decompressive craniectomy lowered ICP to less than 20 mm Hg in 85% of patients. In the 40 patients who had undergone ICP monitoring before decompression, ICP decreased from a mean of 23.9 to 14.4 mm Hg (p < 0.001). Fourteen of 50 patients died, and 16 either remained in a vegetative state (seven patients) or were severely disabled (nine patients). Twenty patients had a good outcome (GOS Score 4–5). Among 30-day survivors, good outcome occurred in 17, 67, and 67% of patients with postresuscitation Glasgow Coma Scale scores of 3 to 5, 6 to 8, and 9 to 15, respectively (p < 0.05). Outcome was unaffected by abnormal pupillary response to light, timing of decompressive craniectomy, brain shift as demonstrated on computerized tomography scanning, and patient age, possibly because of the small number of patients in each of the subsets. Complications included hydrocephalus (five patients), hemorrhagic swelling ipsilateral to the craniectomy site (eight patients), and subdural hygroma (25 patients).

Conclusions

Decompressive craniectomy was associated with a better-than-expected functional outcome in patients with medically uncontrollable ICP and/or brain herniation, compared with outcomes in other control cohorts reported on in the literature.

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Anthony A. Figaji, A. Graham Fieggen and Jonathan C. Peter

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Edward S. Ahn, Courtney L. Robertson, Viktoria Vereczki, Gloria E. Hoffman and Gary Fiskum

Object

Ventilatory resuscitation with 100% O2 after severe traumatic brain injury (TBI) raises concerns about the increased production of reactive oxygen species (ROS). The product of peroxynitrite-meditated tyrosine residue nitration, 3-nitrotyrosine (3-NT), is a marker for oxidative damage to proteins. The authors hypothesized that posttraumatic resuscitation with hyperoxia (100% fraction of inspired oxygen [FiO2] concentration) results in increased ROS-induced damage to proteins compared with resuscitation using normoxia (21% FiO2 concentration).

Methods

Male Sprague–Dawley rats underwent controlled cortical impact (CCI) injury and resuscitation with either normoxic or hyperoxic ventilation for 1 hour (5 rats per group). Twenty-four hours after injury, rat hippocampi were evaluated using 3-NT immunostaining. In a second experiment, animals similarly underwent CCI injury and normoxic or hyperoxic ventilation for 1 hour (4 rats per group). One week after injury, neuronal counts were performed after neuronal nuclei immunostaining.

Results

The 3-NT staining was significantly increased in the hippocampi of the hyperoxic group. The normoxic group showed a 51.0% reduction of staining in the CA1 region compared with the hyperoxic group and a 50.8% reduction in the CA3 region (p < 0.05, both regions). There was no significant difference in staining between the injured normoxic group and sham-operated control groups. In the delayed analysis of neuronal survival (neuronal counts), there was no significant difference between the hyperoxic and normoxic groups.

Conclusions

In this clinically relevant model of TBI, normoxic resuscitation significantly reduced oxidative damage to proteins compared with hyperoxic resuscitation. Neuronal counts showed no benefit from hyperoxic resuscitation. These findings indicate that hyperoxic ventilation in the early stages after severe TBI may exacerbate oxidative damage to proteins.

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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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Joseph C. Noggle, Daniel M. Sciubba, Clarke Nelson, Giannina L. Garcés-Ambrossi, Edward Ahn and George I. Jallo

Object

Treatments for brain abscesses have typically involved invasive craniotomies followed by debridement. These methods often require large incisions with vast exposure and may be associated with high morbidity rates. For supraorbital lesions of the anterior and middle cranial fossa, minimally invasive craniotomies may limit exposure and decrease surgically related morbidity while allowing adequate debridement and decompression. The authors report their experience in treating frontal epidural abscesses in pediatric patients through minimally invasive supraciliary craniotomies over a 4-year period.

Methods

Three pediatric patients with frontal epidural abscesses underwent minimally invasive debridement procedures. Each procedure consisted of a supraciliary incision and a small craniotomy to expose the abscess. All patients underwent pre- and postoperative radiological evaluation including computed tomography and magnetic resonance imaging. Data were collected on preoperative characteristics, operative management, and postoperative outcomes.

Results

Two patients were male and 1 patient was female. The ages of the patients ranged from 6 to 10 years (mean 8 years). A frontal abscess was diagnosed in all patients, and all were treated surgically without perioperative complications. Microbes cultured postoperatively included methicillin-resistant Staphylococcus aureus in 2 patients and Staphylococcus viridans in 1 patient. The mean follow-up duration was 12.3 months. No neurological or vascular complications were noted during follow-up. All patients were treated with antibiotics postoperatively and experienced resolution of symptoms and excellent outcomes.

Conclusions

Frontal epidural abscesses can be adequately and safely debrided via a minimally invasive supraciliary craniotomy. This approach has a cosmetic benefit and may decrease approach-related morbidity.

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Sophia F. Shakur, Matthew J. McGirt, Michael W. Johnson, Peter C. Burger, Edward Ahn, Benjamin S. Carson and George I. Jallo

Object

Angiocentric glioma was recently recognized as a distinct clinicopathological entity in the 2007 World Health Organization Classification of Tumours of the Central Nervous System. The authors present the first 3 pediatric cases of angiocentric glioma encountered at their institution and review the literature of reported cases to elucidate the characteristics and outcomes of pediatric patients with this novel tumor.

Methods

The children in the 3 cases of angiocentric glioma were 10, 10, and 13 years old. Two presented with intractable seizures and 1 with worsening headache and several months of decreasing visual acuity. Twenty-five cases, including the 3 first described in the present paper, were culled from the literature.

Results

In all 3 cases, MR imaging demonstrated a superficial, nonenhancing, T2-hyperintense lesion in the left temporal lobe. Histologically, the tumors were composed of monomorphous cells with a strikingly perivascular orientation that were variably reactive for glial fibrillary acidic protein and epithelial membrane antigen. Surgical treatment resulted in gross-total resection in all 3 cases. By 24, 9, and 6 months after surgery, all 3 patients remained seizure free without focal neurological deficits.

Conclusions

Among 25 cases of angiocentric glioma, seizure was the most common symptom at presentation. Magnetic resonance imaging demonstrated supratentorial, nonenhancing, T1-hypointense, T2-hyperintense lesions. Gross-total resection of this lesion yields excellent results.

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James L. Frazier, G. Steven Bova, Kathryn Jockovic, Elizabeth A. Hunt, Benjamin Lee and Edward S. Ahn

Disseminated intravascular coagulation (DIC) as a complication of surgery for ventriculoperitoneal (VP) shunts is extremely rare, and only one case has been documented in the literature. The authors present the case of a 9-year-old girl with shunted hydrocephalus who presented with a 3-day history of headaches and vomiting. A head CT showed enlarged ventricles compared with baseline. An emergent VP shunt revision was performed, during which an obstructed proximal catheter was found. Immediately after extubation, the patient became apneic and progressed to cardiopulmonary arrest. A breathing tube was reinserted followed by resuscitation attempts that led to extracorporeal membrane oxygenation. Soon after reintubation, bloody drainage was noted in the endotracheal tube, and subsequent laboratory studies were consistent with DIC. The patient died on postoperative Day 1, and autopsy findings confirmed DIC. Note that DIC is a recognized complication of trauma, particularly with brain injury, but it is rare with neurosurgical procedures. Disseminated intravascular coagulation should be considered if excessive bleeding occurs after any brain insult.