Abhishek Ray

Embryonal tumors with abundant neuropil and true rosettes: 2 illustrative cases and a review of the literature

Embryonal tumor with abundant neuropil and true rosettes (ETANTR) is a recently identified variant of primitive neuroectodermal tumor, with fewer than 50 cases reported in the literature to date. Histologically, this tumor has features of ependymoblastoma and neuroblastoma, demonstrating areas of fine fibrillary neuropil intermingled with ependymoblastic rosettes and zones of undifferentiated neuroepithelial cells. However, ETANTR is distinguished pathologically from other embryonal tumors by the striking abundance of neuropil. Clinically, ETANTRs have shown high malignant potential and poor clinical outcome despite aggressive treatment. The authors describe 2 illustrative surgical cases of ETANTR, one involving the longest reported survival in the literature to date. The other had a poor outcome despite high-dose adjuvant chemotherapy with sequential autologous hematopoietic stem cell rescue. The authors review the natural history and treatment strategies available for this unusual malignant pediatric brain tumor.

Deficient T Cell Receptor Excision Circles (TRECs) in autosomal recessive hyper IgE syndrome caused by DOCK8 mutation: implications for pathogenesis and potential detection by newborn screening.

Loss of function of DOCK8 is the major cause of autosomal recessive hyper IgE syndrome, a primary immunodeficiency with adaptive and innate immune dysfunction. Patients affected with ARHIES have atopic dermatitis and recurrent, potentially life-threatening viral and bacterial infections. Three consanguineous Pakistani siblings presented with severe atopic dermatitis and superinfection. Direct sequencing of DOCK8 in all three affected siblings demonstrated homozygosity for a deleterious, novel exon 14 frame shift mutation. Current newborn screening for severe combined immunodeficiency syndrome (SCID) and related T cell disorders relies on the quantitation of T Cell Receptor Excision Cells (TRECs) in dried blood spots (DBS). Significantly, both older affected siblings had undetectable TRECs, and TREC copy number was reduced in the youngest sibling. These findings suggest that AR-HIES may be detected by TREC newborn screening, and this diagnosis should be considered in the evaluation of newborns with abnormal TRECs who do not have typical SCID.

Stereotactic radiosurgery with and without embolization for intracranial arteriovenous malformations: a systematic review and meta-analysis.

OBJECT The effectiveness and risk of stereotactic radiosurgery (SRS) in the management of partially embolized intracranial arteriovenous malformations (AVMs) remain controversial. The aim of this analysis was to assess current evidence regarding the efficiency and safety of SRS for AVM patients with and without prior embolization. METHODS To compare SRS in patients with and without embolization, the authors conducted a meta-analysis of studies by searching the literature via PubMed and EMBASE for the period between January 2000 and December 2013, complemented by a hand search. Primary outcome was the rate of AVM obliteration on a 3-year follow-up angiogram. Secondary outcome was the rate of hemorrhage at 3 years after SRS. Tertiary outcome was permanent neurological deficits related to radiation-induced changes. RESULTS Ten studies eligible for analysis included 1988 patients: 593 had undergone embolization followed by SRS and 1395 had undergone SRS alone. The AVM obliteration rate was significantly lower in patients who had undergone embolization followed by SRS than in those who had undergone SRS alone (41.0% vs 59%, OR 0.46, 95% CI 0.37-0.56, p < 0.00001). However, the rates of hemorrhage (7.3% vs 5.6%, OR 1.17, 95% CI 0.74-1.83, p = 0.50) and permanent neurological deficits related to radiation-induced changes (3.3% vs 3.4%, OR 1.41, 95% CI 0.64-3.11, p = 0.39) were not significantly different between the two groups. CONCLUSIONS Embolization before SRS significantly decreases the AVM obliteration rate. However, there is no significant difference in the risk of hemorrhage and permanent neurological deficits after SRS alone and following embolization. Further validation by well-designed prospective or randomized cohort studies is still needed.

Contemporary management of carotid blowout syndrome utilizing endovascular techniques

To illustrate complex interdisciplinary decision making and the utility of modern endovascular techniques in the management of patients with carotid blowout syndrome (CBS).

Utilization of sinus stents as a novel approach for benign cystic lesions of the sella

Steroid-releasing sinus stents have emerged as a safe and effective tool in endoscopic sinus surgery. In this case report, we present two patients with recurrent cystic sellar masses. Transsphenoidal approach was used to access the sella. Following resection and drainage of the cystic pathology, a Propel (Menlo Park, CA) stent was placed through the corridor of the resection site to stent the cavity open. This is the first report where a steroid-releasing sinus stent was used in the treatment of a sellar lesion. It supports that this technology is safe and effective for use in skull base surgery.

Successful endovascular management of venous sinus thrombosis complicating trans-labyrinthine removal of vestibular schwanomma

Cerebral venous sinus thrombosis (CVST) is a rare complication of surgical treatment of vestibular schwanomma. We present a rare case of extensive venous sinus thrombosis after trans-labyrinthine approach that was refractory to systemic anti-coagulation. Mechanical aspiration thrombectomy was utilized to re-canalize the venous sinuses and resulted in successful resolution of neurological symptoms. Indications of utilizing endovascular approaches are discussed that will enable skull base surgeons to address this uncommon yet potentially fatal complication.

Resection of a Lumbar Intradural Extramedullary Schwannoma: 3-Dimensional Operative Video

This 3-dimensional operative video illustrates resection of a lumbar schwannoma in a 57-yr-old female who presented with right lower extremity numbness, paresthesias, as well as a long history of lower back pain with rest. On magnetic resonance imaging (MRI), there was evidence of an intradural extramedullary enhancing lesion at L5, nearly completely encompassing the spinal canal. This video demonstrates the natural history, treatment options, surgical procedure, risks, and complications of treatment of these types of tumors. The patient underwent a posterior lumbar laminectomy with a midline dural opening for tumor resection. The tumor was encountered intradurally and electromyography recording confirmed that the tumor arose from a lumbar sensory nerve root. The sensory root was then divided and the tumor was then removed. The mass was removed en bloc and histopathologic analysis was consistent with a schwannoma. Postoperative MRI demonstrated gross total resection of the patients neoplasm with excellent decompression of the spinal cord. The patient had an uneventful postoperative course with full recovery and complete resolution of her back pain and leg paresthesias.

Resection of 2 Intradural Extramedullary Cervical Spine Tumors in a Patient With Neurofibromatosis Type 2: 3-Dimensional Operative Video

This 3-dimensional operative video illustrates resection of 2 cervical spine schwannomas in a 19-yr-old female with neurofibromatosis type 2. The patient presented with lower extremity hyperreflexity and hypertonicity. Magnetic resonance imaging (MRI) demonstrated 2 contrast-enhancing intradural extramedullary cervical spine lesions causing spinal cord compression at C4 and C5. The patient underwent a posterior cervical laminoplasty with a midline dural opening for tumor resection. Curvilinear spine cord compression is demonstrated in the operative video. After meticulous dissection, the tumors were resected without complication. The dural closure was performed in watertight fashion followed by laminoplasty using osteoplastic titanium miniplates and screws. Postoperative MRI demonstrated gross total resection with excellent decompression of the spinal cord. The postoperative course was uneventful. The natural history of this disease, treatment options, and potential complications are discussed.

Verapamil-induced breakdown of the blood–brain barrier presenting as a transient right middle cerebral artery syndrome

A middle-aged patient presented for elective embolization of an incidentally found right internal carotid aneurysm. An angiogram was performed, during which the left internal carotid artery was visualized to evaluate a second, small aneurysm. During the embolization of the right internal carotid artery aneurysm, a catheter-induced vasospasm was identified that prompted treatment with intra-arterial verapamil. The procedure was uncomplicated; a postoperative rotational flat-panel computed tomography scan was performed on the angiography table that demonstrated right hemisphere contrast staining. The patient developed a right middle cerebral artery (MCA) syndrome after extubation with repeat cerebral angiography negative for occlusion and magnetic resonance imaging negative for stroke. The patient was observed for 48 hours, during which time the patient had slowly improved. At a six-week follow up visit, the patient had fully recovered. We present an interesting case of a verapamil-induced breakdown of the blood–brain barrier and self-limited right MCA syndrome.

Intraventricular thrombolysis after endovascular treatment of a ruptured arteriovenous malformation

Intraventricular haemorrhage (IVH) secondary to arteriovenous malformation (AVM) rupture carries significant morbidity and mortality. External ventricular drainage of IVH is frequently complicated by thrombus formation within the ventricular catheter and therefore often unsuccessful at treating hydrocephalus in this setting. Intraventricular administration of recombinant tissue-type plasminogen activator (rtPA) has proved successful in the treatment of spontaneous panventricular haemorrhage. However, usage of rtPA is contraindicated in the setting of a ruptured AVM or aneurysm in which the bleeding source has not been secured. There are only a few reports of intraventricular thrombolysis in the treatment of IVH from AVM rupture. We present the case of successful application of rtPA to treat IVH after endovascularly securing the haemorrhage site of the AVM. Intraventricular thrombolysis remains an option for the treatment of IVH in the setting of AVM rupture and should be considered on a case-by-case basis.