Faculty Bibliography

OBJECTIVE: Dermoid and epidermoid cysts rank among the most common pediatric tumors. We analyzed the outcomes of surgical excision of dermal and epidermal inclusion cysts in a large consecutive series of children. METHODS: We retrospectively reviewed 128 consecutive children who underwent calvarial inclusion cyst resection between 2000 and 2010 at NYU Langone Medical Center. Demographic information, neurological exam, lesion location, lesion diameter, type of treatment, extent of resection, time of follow-up, and recurrence were collected. RESULTS: The cohort includes 67 girls (52.3 %) and 61 boys (47.7 %). Age at diagnosis ranged from birth to 6.5 years (mean of 1.2 years) with surgical intervention between 1 month and 20 years of age (1.5 +/- 2.1). Of the 128 patients, 107 underwent open resection. Surgical approach was determined by the senior surgeon. Location, postoperative cosmesis, and family preference were the determining factors. Endoscopic resection was favored with supraorbital and glabellar lesions (75 % endoscopic versus 25 % open) using a rigid scope via a single incision. Erosion of the outer table and involvement of the inner table was noted in 20 patients (15 %), 14 of which were reconstructed using a split thickness calvarial graft. These lesions were noted to be significantly larger than lesions where cranioplasty was not used (1.9 +/- 2.81 cm versus 1.23 +/- 0.98 cm, p = 0.022). Gross total resection was achieved in all cases. DISCUSSION: Complete removal and cure from dermoid and epidermoid inclusion cysts are possible. Complications are few. Endoscopic approaches are useful to improve cosmesis and limit tissue damage for lesions near the orbits.

The authors report the case of 14-year-old girl with a history of myelomeningocele and previously shunt-treated hydrocephalus who presented with right-sided abdominal pain and subcutaneous emphysema that developed over a 1-week period. A CT scan of the patient's abdomen revealed a retained distal ventriculoperitoneal (VP) catheter with air tracking from the catheter to the upper chest wall. Given the high suspicion of the catheter being intraluminal, an exploratory laparotomy was performed and revealed multiple jejunal perforations. The patient required a partial small-bowel resection and reanastomosis for complete removal of the retained catheter. Six other similar cases of bowel perforation occurring in patients with abandoned VP and subdural-peritoneal shunts have been reported. The authors analyzed these cases with regard to age of presentation, symptomatic presentation, management, morbidity, and mortality. While there was 0% mortality associated with bowel perforation secondary to a retained distal VP catheter, the morbidity was significantly high and included peritonitis and small bowel resection.

BACKGROUND: Occipital artery pseudoaneurysms are extremely rare pathologies that manifest after traumatic injury; only 11 cases have been reported in the literature. Because of their low incidence and vague symptoms, the initial diagnosis can be difficult. However, for correctly diagnosed occipital artery pseudoaneurysms, many successful treatment modalities exist. METHODS: We review the pathology of occipital pseudoaneurysms, elucidate the reasons for their rarity, discuss effective diagnostic measures, and discuss the currently available treatment options. We also present a case of a 16-year-old boy who sustained blunt force trauma in May 2014 and presented 6 months later with a painful, pulsatile mass in the occipital region. RESULTS: The patient underwent surgical resection to alleviate the pain and the potential risk of hemorrhage. He experienced complete resolution of pain and associated symptoms. CONCLUSIONS: Our case highlights the fact that occipital swelling, a significant initial sign of pseudoaneurysm development, can be delayed. Therefore, occipital artery pseudoaneurysms cannot be ruled out of the differential diagnosis based on time course alone. Surgical resection is a quick and effective method for relief of severe pain resulting from occipital artery pseudoaneurysms. Although they are rare entities, occipital artery pseudoaneurysms must be considered in the differential diagnosis of cases of pulsatile mass lesions in the posterior scalp.

PURPOSE: Mondini dysplasia is a rare congenital inner ear malformation that presents with abnormal cochlear development with accompanied vestibular dilation and vestibular aqueduct enlargement. This dysfunctional anatomy provides the potential for sensorineural hearing deficits, cerebrospinal fluid leaks, and severe cases of recurrent meningitis. METHODS: We present the case of a child with Mondini dysplasia who presented with unilateral hearing loss and cerebrospinal fluid (CSF) otorrhea that was surgically repaired through a combined middle fossa/transmeatal middle ear approach to alleviate any recurrence of infection and cerebrospinal fluid otorrhea. RESULTS: Postoperatively, the patient remained neurologically stable without any further CSF leakage. CSF cultures revealed a Pseudomonas aeruginosa infection, a rare occurrence within the context of Mondini dysplasia. Retrograde bacterial spread from the external ear canal into the CSF space has been theorized as the possible pathogenesis of the resulting meningitis. The patient was successfully treated with intravenous antibiotics without any neurologic complications. CONCLUSIONS: Although Mondini dysplasia is a rare malformation, the life-threatening sequelae of meningitis that can result from the dysfunctional anatomy makes it a condition that requires elevated clinical vigilance, especially when considering children with hearing loss associated with recurrent meningitis, otorrhea, or rhinorrhea.

Object Subependymal giant cell astrocytomas (SEGAs) are benign tumors, most commonly associated with tuberous sclerosis complex (TSC). The vast majority of these tumors arise from the lateral ependymal surface adjacent to the foramen of Monro, therefore potentially encroaching on one or both foramina, and resulting in obstructive hydrocephalus that necessitates surgical decompression. The indications for surgery, intraoperative considerations, and evolution of the authors' management paradigm are presented. Methods Patients with TSC who underwent craniotomy for SEGA resection at New York University Langone Medical Center between January 1997 and March 2011 were identified. Preoperative imaging, clinical characteristics, management decisions, operative procedures, and outcomes were reviewed. Results Eighteen patients with TSC underwent 22 primary tumor resections for SEGAs. The indication for surgery was meaningful radiographic tumor progression in 16 of 21 cases. The average age at the time of operation was 10.3 years. Average follow-up duration was 52 months (range 12-124 months). The operative approach was intrahemispheric-transcallosal in 16 cases, transcortical-transventricular in 5, and neuroendoscopic in 1. Nine tumors were on the right, 9 on the left, and 3 were bilateral. Gross-total resection was documented in 16 of 22 cases in our series, with radical subtotal resection achieved in 4 cases, and subtotal resection (STR) in 2 cases. Two patients had undergone ventriculoperitoneal shunt placement preoperatively and 7 patients required shunt placement after surgery for moderate to severe ventriculomegaly. Two patients experienced tumor progression requiring reoperation; both of these patients had initially undergone STR. Conclusions The authors present their management strategy for TSC patients with SEGAs. Select patients underwent microsurgical resection of SEGAs with acceptable morbidity. Gross-total resection or radical STR was achieved in 90.9% of our series (20 of 22 primary tumor resections), with no recurrences in this group. Approximately half of our patient series required CSF diversionary procedures. There were no instances of permanent neurological morbidity associated with surgery.

BACKGROUND: Spontaneous intracranial hypotension is an uncommon clinical entity. Heritable connective tissue disorders (HCTD), such as Marfan syndrome, are frequently implicated as an underlying cause, due to dural structural weaknesses that predispose patients to spontaneous cerebrospinal fluid (CSF) leak. Due to the high prevalence of multi-system disease in HCTD, diagnosis and treatment are often complicated. CASE DESCRIPTION: We present a 58-year-old female with Marfan syndrome on anticoagulation for a mechanical aortic valve replacement who came to medical attention with severe, acute-onset headache following a straining episode. Noninvasive magnetic resonance (MR) myelography confirmed thoracic CSF extravasations and multiple lumbar diverticula. The patient was treated conservatively and her symptoms resolved. CONCLUSION: We discuss the common presentation, diagnostic tools, and treatment options for spontaneous CSF leaks in patients with Marfan syndrome or related HCTD with an emphasis on noninvasive modalities and a review of the major radiographic criteria used to diagnose dural abnormalities, such as dural ectasia.

Neurofibromatosis type 2 (NF2) is an autosomal dominant syndrome with a prevalence of approximately 1 in 30,000. NF 2 is characterized by bilateral vestibular schwannomas, as well as meningiomas, ependymomas and gliomas. Currently, surgical resection and radiotherapy represent the mainstay of treatment, although new studies suggest a role for certain chemotherapeutic agents. Intravenous administration of Bevacizumab (Avastin, Genetech Pharmaceuticals) has been shown to be active in the treatment of vestibular schwannomas. The IV route of administration, however, carries a risk of known systemic side-effects such as bowel perforation, wound dehiscence and pulmonary embolism. In addition, the percentage of drug that reaches the tumor site may be restricted by the blood tumor barrier. This report describes the super-selective intra-arterial infusion of Bevacizumab following blood brain barrier disruption for the treatment of vestibular schwannomas in three patients with Neurofibromatosis type 2. It represents the first time such a technique has been performed for this disease. Additionally, this method of drug delivery may have important implications in the treatment of patients with vestibular schwannomas associated with Neurofibromatosis type 2.

Subependymal giant cell astrocytomas (SEGAs) are benign tumors, most commonly associated with tuberous sclerosis complex (TSC). Arising from the lateral ependymal surface, these tumors may obstruct one or both foramina of Monro, resulting in hydrocephalus and often requiring treatment. Although interhemispheric-transcallosal and transcortical-transventricular approaches have been the standard methods for resecting these tumors, advances in neuroendoscopic techniques have expanded SEGAs as a potential target for endoscopic resection. The authors present a case of an endoscopically resected SEGA with stereotactic guidance in a 4-year-old girl with TSC. A gross-total resection of an enlarging SEGA was achieved. This represents one of the early case reports of endoscopically resected SEGAs. Although recent advances in medical treatment for SEGAs with mammalian target of rapamycin (mTOR) pathway inhibitors have shown promising initial results, the long-term safety and efficacy of mTOR inhibitors has yet to be determined. The propensity of these tumors to cause obstructive hydrocephalus requires that a surgical option remain. Neuroendoscopic approaches may allow a safe and effective technique.

OBJECT: Techniques for the placement of intrathecal baclofen (ITB) systems have been described in detail, with special consideration given to complications from hardware placement. Risks including catheter kinking and migration, hardware erosion through the skin, and lumbar CSF leak are elevated given the often-low body mass index and poor nutritional status of this patient population. The bulk of a spinal catheter and fascial connector within the lumbar wound may increase the potential for the aforementioned risks, leading to potential risks for wound infection and breakdown. The authors' experience has led them to develop a novel method of paraspinal subfascial lumbar catheter placement to address these risks. The authors describe a novel lumbar intrathecal catheter placement technique as part of the ITB system. METHODS: All patients undergoing placement of an ITB system by the senior author at New York University Langone Medical Center between July 2010 and March 2011 underwent paraspinal subfascial lumbar catheter placement. Patients were followed-up by the surgeon 2 weeks after implantation and followed up and managed by their physiatrist thereafter, for an average of 5 months (range 0.5-9 months). Results Of the 20 patients who underwent this method of intrathecal catheter placement, none developed any hardware erosion, catheter migration, or CSF leak. One patient developed an abdominal wound infection 3 weeks after implantation, necessitating pump removal. CONCLUSIONS: In this initial short-term experience, subfascial placement of the lumbar spine intrathecal catheter may be an improvement over the traditional method of catheter placement. There is reduced risk of catheter migration or kinking, hardware erosion, CSF leak, and decreased operative time, all yielding a decreased reoperation rate in this vulnerable population.

The authors report the first case of a Wilms tumor (WT) with diffuse anaplasia metastatic to the brain in a 13-year-old girl with a history of neurofibromatosis Type 1. At presentation, the metastatic tumor had radiological features that suggested a meningioma. Histologically it was characterized by striking anaplasia and features similar to the patient's previously resected WT with diffuse anaplasia.