Brian P Walcott MD Massachusetts General Hospital Department of Neurosurgical Surgery 55 Fruit Street White Building, Room 502 Boston MA 02114 USA
walcott.brian@mgh.harvard.edu
Seton Hall University - BS - 2003 Loyola University Chicago School of Medicine - MD- 2008 Harvard Medical School & Massachusetts General Hospital - Intern, General Surgery - 2008-2009 Harvard Medical School & Massachusetts General Hospital - Resident, Neurological Surgery - 2009 -->
Abstract: Generalized dystonic syndromes may escalate into persistent episodes of generalized dystonia known as status dystonicus that can be life-threatening due to dystonia-induced rhabdomyolysis and/or respiratory compromise. Treatment of these conditions usually entails parenteral infusion of antispasmodic agents and sedatives and occasionally necessitates a medically induced coma for symptom control. The authors report a series of 3 children who presented with medically intractable, life-threatening status dystonicus and were successfully treated with bilateral pallidal deep brain stimulation. Bilateral globus pallidus internus stimulation appears to be effective in the urgent treatment of medically refractory and life-threatening movement disorders.
Abstract: ObjectivePediatric pial arteriovenous fistulae (pAVF) are rare vascular lesions of the CNS, reported to have up to a 25% association with hereditary hemorrhagic telangiectasia. The presentation, treatment and syndromes associated with pAVF in children are reported here.DesignA pediatric database for pAVF was retrospectively reviewed. Patients with carotid-cavernous fistulae, dural arteriovenous fistulae, brain arteriovenous malformations and vein of Galen malformations were excluded. Radiographic outcome was assessed using digital subtraction angiography, and clinical outcome by the Functional Status Scale (6=normal, maximal incapacity=30).ResultsBetween July 2003 and June 2011, seven patients with pAVF (six intracranial and one spinal) were treated. Mean age was 4.2 years. The most common clinical presentation was high output cardiac failure (43%). Two patients (29%) harbored a known mutation in the RASA1 gene, associated with a hereditary vascular syndrome: capillary malformation-arteriovenous malformation. No patient had hereditary hemorrhagic telangiectasia. Treatment resulted in complete lesional obliteration in six of seven patients, with treatment ongoing in the seventh. Five of seven patients had combined endovascular and surgical treatment while two underwent endovascular embolization alone. Functional Status Scale scores at the most recent follow-up were 6 in all but one patient who had presented with a pretreatment hemianopsia.ConclusionTreatment is effective in obliterating pAVF in children, with an excellent prognosis seen in our cohort. Genetic screening is indicated, with capillary malformation-arteriovenous malformation being the most frequently seen syndrome. No patients had hemorrhagic hereditary telangiectasia.
Abstract: Traumatic brain injury is a heterogeneous entity that encompasses both surgical and non-surgical conditions. Surgery may be indicated with traumatic lesions such as hemorrhage, fractures, or malignant cerebral edema. However, the neurological exam may be clouded by the effects of medications administered in the field, systemic injuries, and inaccuracies in hyperacute prognostication. Typically, neurological injury is considered irreversible if diffuse loss of grey / white matter differentiation or if brainstem hemorrhage (Duret hemorrhage) exists. We aim to characterize a cohort of patients undergoing bilateral hemicraniectomy for severe traumatic brain injury. A retrospective, consecutive cohort of adult patients undergoing craniectomy for trauma was established between the dates of Jan 2008 and Nov 2011. The primary outcome of the study was in-hospital mortality. Secondary outcomes were ICU length of stay, surgical complications, and Glasgow Outcome Score at most recent follow-up. During the study period, 210 patients undergoing craniectomy for traumatic mass occupying lesion (epidural hematoma, subdural hematoma, parenchymal contusion) were analyzed. Of those, nine met study criteria. In-hospital mortality was 67 % (six of nine patients). The average ICU length of stay was 12 days. The GOS was 3 in surviving patients. Bilateral hemicraniectomy is a heroic intervention for patients with severe TBI but can be a life saving procedure.
Abstract: ObjectiveDural arteriovenous fistulae (dAVF) are rare vascular lesions of the CNS with potentially significant morbidity and mortality. Our experience in the treatment of children with dAVF is reported.DesignOur neurosurgical and neurointerventional pediatric database was retrospectively reviewed for patients with dAVF. Brain arteriovenous malformations, pial fistulae, vein of Galen malformations and extracranial fistulae were excluded. Angiography was used to assess radiographic outcome in all cases. Clinical outcome was assessed by the pediatric Functional Status Scale (6=normal, maximal incapacity=30).ResultsBetween July 2003 and June 2011, seven patients with dAVF were treated, with a mean age at presentation of 4.8 years. Presenting symptoms included facial venous prominence, headache, macrocephaly and symptoms of elevated intracranial pressure; one patient (14%) had asymptomatic dAVF discovered on imaging follow-up after craniotomy for cavernous malformation. Two cases (28%) were associated with vascular anomaly syndromes, PHACE association and PTEN associated syndrome. Venous sinus thrombosis was identified in four patients (57%) and was associated with a systemic hypercoagulable state or trauma. Complete obliteration was achieved in six of seven patients. Treatment was exclusively endovascular in six patients and by combined surgical/endovascular means in the remaining patient. No treatment complications were experienced. Functional Status Scale scores at an average of 2 years of follow-up were 6 in all patients.ConclusionTreatment is effective in the obliteration of dAVF in children and is well tolerated, with patients having excellent prognoses. Genetic screening and hypercoagulable workup are indicated, particularly when other anomalies or sinus thrombosis coexist.
Abstract: Isolated bilateral abducens (sixth) nerve palsy is rare in the setting of trauma. To date, most cases have been reported in patients who sustain cranial fractures or have other acute intracranial pathologies, including acute hemorrhage. We describe the case of a 41-year-old man who presented with bilateral abducens nerve palsy in the setting of acute head trauma without evidence of cranial fractures or other acute intracranial pathology. Six months after the initial injury, he regained bilateral function of his abducens nerves with intact extraocular muscle movements. Full recovery is the natural history in the majority of traumatic abducens nerve palsies, and this is an important consideration when counseling patients with such injuries.
Abstract: Chordoma is a rare bone cancer that is aggressive, locally invasive, and has a poor prognosis. Chordomas are thought to arise from transformed remnants of notochord and have a predilection for the axial skeleton, with the most common sites being the sacrum, skull base, and spine. The gold standard treatment for chordomas of the mobile spine and sacrum is en-bloc excision with wide margins and postoperative external-beam radiation therapy. Treatment of clival chordomas is unique from other locations with an enhanced emphasis on preservation of neurological function, typified by a general paradigm of maximally safe cytoreductive surgery and advanced radiation delivery techniques. In this Review, we highlight current standards in diagnosis, clinical management, and molecular characterisation of chordomas, and discuss current research.
Abstract: OPINION STATEMENT: Managing patients with malignant cerebral infarction remains one of the foremost challenges in medicine. These patients are at high risk for progressive neurologic deterioration and death due to malignant cerebral edema, and they are best cared for in the intensive care unit of a comprehensive stroke center. Careful initial assessment of neurologic function and of findings on MRI, coupled with frequent reassessment of clinical and radiologic findings using CT or MRI are mandatory to promote the prompt initiation of treatments that will ensure the best outcome in these patients. Significant deterioration in either neurologic function or radiologic findings or both demand timely treatment using the best medical management, which may include osmotherapy (mannitol or hypertonic saline), endotracheal intubation, and mechanical ventilation. Under appropriate circumstances, decompressive craniectomy may be warranted to improve outcome or to prevent death.
Abstract: Central neurocytomas (CN) are benign central nervous system (CNS) tumors of neuroglial origin that represent 0.25 to 0.5% of all intracranial tumors in adults and an even smaller proportion of pediatric CNS tumors. These tumors characteristically occur in the subependymal layer of the lateral ventricle near the foramen of Monro and appear as sharply demarcated, solitary lesions. Surgical resection is considered curative, as the reported recurrence rate is less than 5% for patients with localized disease. In this report, we describe the case of a three-year-old boy with a diffuse CN with craniospinal dissemination identified at the time of diagnosis. Given the extensive nature of the disease, surgical resection was not indicated and he underwent a chemotherapeutic regimen of vincristine and carboplatin. At 18months followup, the patient has completed 6 of 8 total cycles of vincristine and carboplatin and serial imaging shows stable disease within the craniospinal axis.
Abstract: Spine injury resulting from migration of previously implanted appendicular skeleton fixation hardware is rare. We present a 41-year-old man who had Steinmann fixation pins placed for a left clavicular fracture 2years prior. He presented with a burning sensation over his biceps bilaterally and numbness over the left anterior chest and abdomen following a significant blunt traumatic injury. A CT scan revealed migration of a fractured Steinmann pin entering the left C8 neural foramen, traversing anterior to the spinal cord. The patient underwent a left C7 hemilaminectomy, foraminal decompression, and first rib resection to identify the extraforaminal portion of the pin and remove it under direct vision. He recovered uneventfully. We conclude that a principle of safe surgical removal includes adequate exposure to allow for direct visualization of the pin and neural structures. We review the evaluation and management strategies of this unusual condition.
Abstract: Fractures of the anterior skull base can lead to pseudoaneurysm formation as a result of direct injury to a vessel wall. Pseudoaneurysms in this location are challenging to treat, as both perforator and distal blood supply must be maintained. Additionally, traumatic skull base fractures can lead to a rare condition of cerebral blood vessel herniation through the bony defect, further complicating treatment planning. Treatment of these lesions is essential to (1) prevent the occurrence of potentially fatal subarachnoid hemorrhage and (2) prevent dissection from propagating and compromising blood flow to distal vessels, perforators, and even parent vessels. We present a unique case of a traumatic proximal anterior cerebral artery pseudoaneurysm, herniating through a skull base defect. Treatment consisted of aneurysm trapping and bypass with skull base reconstruction.
Abstract: Herniated intervertebral discs can result in pain and neurological compromise. Treatment for this condition is categorized as surgical or non-surgical. We sought to identify trends in inpatient surgical management of herniated intervertebral discs using a national database.
Abstract: Cerebral cavernous malformations (CCM) are known to occur in both sporadic and familial forms. To date, there has been no identified association of CCM with glioblastoma multiforme. We present a 69-year-old woman with a 14year history of multiple CCM who developed progressive aphasia. She had no radiation exposure and had only undergone a single computed tomography scan in her entire life. MRI demonstrated irregular gadolinium enhancement in the area of a prior stable CCM, suspicious for a high grade tumor. Stereotactic biopsy revealed a glioblastoma multiforme. This is a unique case of glioblastoma multiforme arising from the "site" of a known CCM. We review the literature on the genetics of cavernous malformations and propose a mechanism for the tumorigenic potential of these vascular malformations.
Abstract: Hemifacial spasm (HFS) is caused by arterial or venous compression of cranial nerve VII at its root exit zone. Traditionally, microvascular decompression of the facial nerve has been an effective treatment for posterior inferior and anterior inferior cerebellar artery as well as venous compression. The traditional technique involves Teflon felt or another construct to cushion the offending vessel from the facial nerve, or cautery and division of the offending vein. However, using this technique for severe vertebral artery (VA) compression can be ineffective and fraught with complications. The authors report the use of a new technique of VA pexy to the petrous or clival dura mater in patients with HFS attributed to a severely ectatic and tortuous VA, and detail the results in a series of patients.
Abstract: A 75-year-old woman with a history of stage IV metastatic melanoma underwent treatment with the CTLA-4 blocking agent Ipilimumab. She presented 2Â months after initiating treatment with a severe headache. Laboratories were consistent with severe hyponatremia. MRI of the brain revealed enlargement of the pituitary gland, enhancement of the infundibulum, and an enhancing, centrally necrotic foci in the anterior pituitary. Based on the clinical and radiographic findings, she was diagnosed with treatment-related syndrome of inappropriate antidiuretic hormone secretion (SIADH). Effective treatment consisted of fluid restriction, hyperosmolar therapy, and steroids.
Abstract: BACKGROUND: Iatrogenic injury to the vertebral artery during posterior cervical fusion is a rare and potentially disastrous complication. Differentiating arterial from brisk venous bleeding would be ideal to assist in the intra-operative management. Definitive angiography is typically not feasible during most routine spine surgery. CASE DESCRIPTION: We describe the case of a patient undergoing an occipitocervical fusion, where brisk bleeding was encountered during dissection of the CB lateral mass. While the dissection was thought to be superficial to critical structures, the nature of the hemorrhage could not be definitely determined by visual inspection by two senior surgeons. The hemorrhage did not readily cease with standard maneuvers such as, the application of various hemostatic agents. Simultaneous blood gas analysis was performed on samples obtained from the patient's radial artery and from the hemorrhage in the operative bed. Comparative analysis concluded that the bleeding encountered in the surgical field was venous in nature. CONCLUSION: Blood gas analysis can be a useful adjunct in determining the nature of hemorrhage from vascular structures in spine surgery when visual inspection is indeterminate.
Abstract: Incidental vertebral lesions on imaging of the spine are commonly encountered in clinical practice. Contributing factors include the aging population, the increasing prevalence of back pain, and increased usage of MR imaging. Additionally, refinements in CT and MR imaging have increased the number of demonstrable lesions. The management of incidental findings varies among practitioners and commonly depends more on practice style than on data or guidelines. In this article we review incidental findings within the vertebral column and review management of these lesions, based on available Class III data.
Abstract: Peptic ulcer disease can lead to serious complications including massive hemorrhage or bowel perforation. The modern treatment of peptic ulcer disease has transitioned from the control of gastric acid secretion to include antibiotic therapy in light of the identification of Helicobacter pylori as a causative infectious organism. We sought to determine trends related to this discovery by using a national database.
Abstract: Randomized trials have demonstrated the efficacy of craniectomy for the treatment of malignant cerebral edema following ischemic stroke. We sought to determine the prevalence and outcomes related to this by using a national database.
Abstract: Dermal sinus tracts are a form of spinal dysraphism that arises from a failure of dysjunction early in embryogenesis. They are diagnosed in pediatric patients and who present with a dimple, infection, or neurologic deficit. The tract is surgically excised en bloc to avoid contamination from the tract, which harbors bacteria. However, dermal sinus tracts typically terminate intradurally, rendering their en bloc excision difficult. To avoid entering the tract, allowing for an en bloc excision, we modified the usual technique employed for accessing the spinal intradural space. An en bloc excision of the dermal sinus tract was successfully performed. The patient recovered from the procedure neurologically intact and her postoperative course was uncomplicated. We conclude that en bloc excision of a dermal sinus tract down to the intradural space is feasible with modifications to standard operative technique.
Abstract: OBJECTIVE: To examine whether multiple aneurysms located in the anterior cerebral artery (ACA), middle cerebral artery (MCA), or internal carotid artery (ICA) could be treated through single-stage, ipsilateral dual craniotomies. METHODS: Investigators reviewed records of nine patients who underwent dual ipsilateral craniotomies through one incision for surgical treatment of multiple aneurysms in the anterior circulation at a single institution from 1994-2010. In all cases, a single-stage pterional and frontal interhemispheric approach through two separate, ipsilateral craniotomies under a single, extended pterional incision was used. RESULTS: Dual craniotomies through one incision were performed on nine patients with multiple aneurysms without complications. This series included eight women and one man with an average age of 57 years. The mean number of aneurysms treated was 2.7 (range 2-5 aneurysms). Most patients underwent elective treatment. The pterional craniotomy approach was used to treat MCA and ICA aneurysms, whereas distal ACA aneurysms were treated through the frontal parasagittal craniotomy approach. All aneurysms were successfully treated via clip ablation. There were no perioperative or postoperative complications at an average follow-up of 29 months (range 1-131 months). CONCLUSIONS: Single-stage, ipsilateral dual pterional and frontal craniotomies through one incision constitute a safe approach that can be employed for the effective surgical treatment of multiple aneurysms in joint unilateral and axial locations with excellent clinical results.
Abstract: Cerebral edema is a common finding in a variety of neurological conditions, including ischemic stroke, traumatic brain injury, ruptured cerebral aneurysm, and neoplasia. With the possible exception of neoplasia, most pathological processes leading to edema seem to share similar molecular mechanisms of edema formation. Challenges to brain-cell volume homeostasis can have dramatic consequences, given the fixed volume of the rigid skull and the effect of swelling on secondary neuronal injury. With even small changes in cellular and extracellular volume, cerebral edema can compromise regional or global cerebral blood flow and metabolism or result in compression of vital brain structures. Osmotherapy has been the mainstay of pharmacologic therapy and is typically administered as part of an escalating medical treatment algorithm that can include corticosteroids, diuretics, and pharmacological cerebral metabolic suppression. Novel treatment targets for cerebral edema include the Na(+)-K(+)-2Cl(-) co-transporter (NKCC1) and the SUR1-regulated NC(Ca-ATP) (SUR1/TRPM4) channel. These two ion channels have been demonstrated to be critical mediators of edema formation in brain-injured states. Their specific inhibitors, bumetanide and glibenclamide, respectively, are well-characterized Food and Drug Administration-approved drugs with excellent safety profiles. Directed inhibition of these ion transporters has the potential to reduce the development of cerebral edema and is currently being investigated in human clinical trials. Another class of treatment agents for cerebral edema is vasopressin receptor antagonists. Euvolemic hyponatremia is present in a myriad of neurological conditions resulting in cerebral edema. A specific antagonist of the vasopressin V1A- and V2-receptor, conivaptan, promotes water excretion while sparing electrolytes through a process known as aquaresis.
Abstract: A cerebrospinal fluid (CSF) leak following skull base surgery can lead to meningitis, impaired wound healing, and often requires re-operation and/or CSF diversion. Thirty-two patients underwent a presigmoid, transpetrosal approach to skull base aneurysms and tumors. A vascularized temporalis muscle flap was utilized during the closure of the initial skull base reconstruction in 18 of the 32 patients. A temporary CSF diversion was utilized in 23 of the 32 patients. A permanent shunt was placed in eight patients. One patient developed a postoperative CSF leak from the contralateral ear due to a congenital abnormality in the middle ear. Another patient, who did not have a vascularized temporalis muscle flap reconstruction, developed a postoperative CSF leak in the context of an operation for recurrent tumor and prior radiation treatment. CSF diversion and vascularized temporalis muscle flaps are effective in preventing the development of postoperative CSF leaks following petrosectomy.
Abstract: Medical treatment of idiopathic intracranial hypertension is often ineffective. Cerebrospinal fluid diversion or optic nerve sheath fenestration is employed when medical therapy fails. Here, we describe a case of a 13-year-old girl with idiopathic intracranial hypertension refractory to long-term trials of acetazolamide and furosemide at maximally tolerated doses. After declining surgical intervention despite progression of her visual symptoms, a trial of bumetanide (0.25 mg daily) monotherapy was successful in resolution of the patient's symptoms. These results suggest bumetanide could be effective in the treatment of idiopathic intracranial hypertension, perhaps by restoring the balance between cerebrospinal fluid formation and absorption and/or by altering the volume or ionic composition of the brain's extracellular fluid compartment.
Abstract: Spinal subdural empyemas are rare. We describe a 53-year-old male who presented with back pain, mental status changes, and sepsis. Five days prior he had undergone a triamcinolone and lidocaine injection of the acromial bursa. He also had a remote history of epidural steroid injection for thoracic back pain. Two lumbar MRI conducted 62 hours apart revealed a newly developed subdural empyema that was successfully treated with surgical evacuation and post-operative antibiotics.
Abstract: Clinical studies from over half a century ago suggested efficacy of a variety of diuretics in focal and generalized epilepsies as well as in status epilepticus, but these findings have not been translated into modern epilepsy training or practice. Recent advances in our understanding of neuronal maturation and the pathophysiology of neonatal seizures provide fresh insight into the mechanisms by which diuretics might reduce susceptibility to seizures. In vitro and in vivo rodent studies and human epilepsy surgical cases have shown that specific diuretic agents targeting the cation-chloride cotransporters decrease neuronal synchrony and neuronal hyperexcitability. These agents are thought to convey their antiepileptic activity by either expanding the extracellular space or promoting a cellular chloride transport balance that reflects a more developmentally "mature," less excitable state. It may be time to reexamine whether diuretics could serve as adjunctive therapies in the treatment of refractory epilepsies.
Abstract: BACKGROUND AND IMPORTANCE:: Cerebral ventricular non-communication has been described in the setting of infection and acutely in the setting of intracranial hemorrhage. We describe the first adult case series of individuals who developed delayed isolated fourth ventricles after rupture of intracranial posterior circulation aneurysms and define treatment modality. CLINICAL PRESENTATION:: A retrospective review was performed of all patients with aneurysms treated at a single institution from 2005 to 2009. Both microsurgical obliteration and endovascular cases were queried. Of 1044 aneurysms treated in this period, three patients were identified who required fourth ventricular shunting, for the treatment of the isolated ventricle. All three patients underwent microsurgical clip obliteration of their aneurysms and had subsequent frontal approach ventriculo-peritoneal cerebrospinal fluid diversion. These patients had no evidence of infection of the cerebrospinal fluid as measured by serial cultures. Subsequently, all three patients presented in a delayed fashion with symptoms attributable to a dilated fourth ventricle and syringomyelia or syringobulbia. Either exploration or percutaneous tapping confirmed the function of the supratentorial shunt. These patients then underwent fourth ventriculo-peritoneal cerebrospinal fluid diversion using a low-pressure shunt system. The symptoms attributable to the isolated fourth ventricle resolved, rapidly, in all three patients after shunting. This clinical improvement correlated with the fourth ventricular size. CONCLUSION:: Isolated fourth ventricle, in an adult, is a rare phenomenon associated with intracranial posterior circulation aneurysm rupture treated with microsurgical clip obliteration. Fourth ventriculo-peritoneal cerebrospinal fluid diversion is effective at resolving the symptoms attributed to the trapped ventricle and associated syrinx.
Abstract: Metastatic vertebral body and spinal epidural lesions cause significant pain and neurological morbidity and negatively impact quality of life and survival. In instances of metastatic epidural spinal cord compression, treatment typically involves surgery and radiotherapy. The incidence of spinal metastases in breast cancer patients is high. In the light of recent improvements in survival among some patients with breast cancer, we reviewed the treatments and outcomes for patients with breast cancer who presented to our institution with metastatic epidural spinal cord compression. We identified all patients undergoing open surgery for the treatment of breast cancer metastases to the spine at our center from 1 January 2001 to 31 December 2009. We retrospectively reviewed records for the details of medical history, treatment, surgery, radiographic imaging, and follow-up. The Death Master File from the United States Social Security Administration was queried to identify the date of death where the medical record was incomplete. Outcomes were assessed by overall survival as well as preoperative and postoperative ambulatory status, bladder function, and the American Spinal Injury Association impairment classification system (ASIA). A total of 15 female patients were identified as having surgical intervention directly related to breast cancer metastasis to the spine. Most lesions (12/15) were located in the anterior vertebral column (vertebral body and/or pedicle). Two patients required re-operation, one for epidural fluid collection and one for infection. Roughly half of the patients (8/15) had well-controlled systemic disease at the time of surgery. Five patients had non-contiguous metastatic lesions elsewhere in the spine. Median survival following surgery was 1,025 days; control of systemic disease did not predict duration of postoperative survival. Seven patients had documented improvement in their ability to ambulate in the first 30 days following surgery. Bladder function was preserved in all. No patient deteriorated; and five patients had postoperative improvement of their ASIA impairment scale grade. We concluded that aggressive therapy, including surgery, is warranted for patients with symptomatic metastatic epidural spinal cord compression from breast cancer, including in the setting of advanced and progressive systemic disease.
Abstract: Chiari malformations (Types I-IV) are abnormalities of the posterior fossa that affect the cerebellum, brainstem, and the spinal cord with prevalence rates of 0.1%-0.5%. Case reports of familial aggregation of Chiari malformation, twin studies, cosegregation of Chiari malformation with known genetic conditions, and recent gene and genome-wide association studies provide strong evidence of the genetic underpinnings of familial Chiari malformation. The authors report on a series of 3 family pairs with Chiari malformation Type I: 2 mother-daughter pairs and 1 father-daughter pair. The specific genetic causes of familial Chiari malformation have yet to be fully elucidated. The authors review the literature and discuss several candidate genes. Recent advances in the understanding of the genetic influences and pathogenesis of familial Chiari malformation are expected to improve management of affected patients and monitoring of at-risk family members.
Abstract: Resolution of syringomyelia is common following hindbrain decompression for Chiari malformation, yet little is known about the kinetics governing this process. The authors sought to establish the volumetric rate of syringomyelia resolution.
Abstract: The clinical benefit of helicopter transport over ground transportation for interfacility transport is unproven. We sought to determine actual practice patterns, utilization, and outcomes of patients undergoing interfacility transport for neurosurgical conditions.
Abstract: Ligamentum flavum is generally resected with impunity when a laminectomy is performed; it is a strong ligament and its removal may not be inconsequential. We sought to examine the consequence of resection of ligamentum flavum as it pertains to the formation of synovial cysts. Following IRB approval, we retrospectively reviewed the charts of consecutive patients who underwent a laminectomy for any diagnosis during the years 2009-2010. Exclusions were made for patients undergoing resection of a synovial cyst, laminectomy done as part of a fusion, and microdiscectomy. A total of 201 laminectomies were performed. 10 instances of post-laminectomy synovial cyst occurred in only the lumbar spine. Synovial cysts occurred exclusively after surgery for stenosis (n=10). Laminectomy and resection of the ligament flavum is a risk factor for the subsequent formation of a synovial cyst. Secondary synovial cyst formation should be suspected in individuals who develop radiculopathy after laminectomy for stenosis.
Abstract: While the trend for endovascular therapy of posterior circulation aneurysms is permeating, cerebrovascular bypass remains essential in the armamentarium for complex lesions not amendable to these techniques. This review discusses the microsurgical anatomy of the posterior fossa intracranial circulation, as well as the techniques and outcomes related to cerebrovascular bypass.
Abstract: Objective Cerebral arteriovenous malformations (AVMs) are vascular lesions that are amenable to various treatment modalities including stereotactic radiosurgery, fractionated radiotherapy, endovascular embolization, microsurgical obliteration or combined modality treatment. A potential complication of endovascular therapy with embolization material is microcatheter entrapment. We report on a patient for whom surgery was combined with endovascular embolization to obliterate an AVM and retrieve an entrapped endovascular microcatheter. Participant A 52-year-old woman suffered a left parietal hemorrhage from an AVM. She underwent staged endovascular embolization of the lesion using Onyx material. During the second stage of the embolization, the microcatheter (Marathon Flow Directed Microcatheter; eV3 Neurovascular, Inc., Irvine, CA, USA) was retained in the Onyx plug. It was decided to section the microcatheter at the groin and proceed with microsurgical obliteration of the AVM, with removal of the entrapped microcatheter remnant. Intervention The AVM was dissected circumferentially allowing the meticulous obliteration of the feeding vessels. A single remaining feeding vessel originating from the distal anterior cerebral artery was identified and suspected to contain the entrapped microcatheter. The location was confirmed using stereotactic guidance (BrainLab, Munich, Germany) and the vessel was then sectioned allowing complete removal of the AVM. The microcatheter (102 cm) was then extracted cranially using gentle traction. Conclusion This demonstrates the first incidence of microcatheter removal after procedural entrapment in Onyx embolization material.
Abstract: Disorders of the spine are common in clinical medicine, and spine surgery is being performed with increasing frequency in the US. Although many patients with an established diagnosis of a true surgically treatable lesion are referred to a neurosurgeon, the evaluation of patients with spinal disorders can be complex and fraught with diagnostic pitfalls. While "common conditions are common," astute clinical acumen and vigilance are necessary to identify lesions that masquerade as surgically treatable spine disease that can lead to erroneous diagnosis and treatment. In this review, the authors discuss musculoskeletal, peripheral nerve, metabolic, infectious, inflammatory, and vascular conditions that mimic the syndromes produced by surgical lesions. It is possible that nonsurgical and surgical conditions coexist at times, complicating treatment plans and natural histories. Awareness of these diagnoses can help reduce diagnostic error, thereby avoiding the morbidity and expense associated with an unnecessary operation.
Abstract: We present a 33-year-old man with 5-year history of low back pain who presented with an enlarging right calf. The patient underwent an extensive workup including biopsy without diagnosis. The patient's examination was significant for diminished pinprick sensation in the right L5/S1 dermatome. Reflexes were absent in the right ankle. The circumference of the right calf (58cm) was twice that of the left. MRI revealed a herniated lumbar disc at the L5/S1 level. He then underwent a L5/S1 microdiscectomy. Following this surgery, the patient noted complete resolution of all sensory deficits in his lower extremity. His calf circumference had decreased by 5cm at 4months and by a total of 8cm at his 2-year post-operative visit. Histological examination of the affected muscle demonstrated severe grouped atrophy of both type I and type II fibers. There was also evidence of compensatory fiber hypertrophy as well as fiber splitting. We concluded that the patient suffered from a herniated lumbar disc causing radiculopathy with calf hypertrophy (neurogenic hypertrophy). To our knowledge this is the first report of both grouped atrophy and compensatory hypertrophy of both muscle fiber types seen in this phenomenon.
Abstract: Cutaneous scalp hemangiomas may herald the presence of occult intracranial hemangiomas. A previously healthy 4-month-old girl presented with a bleeding scalp hemangioma, a bulging fontanel, and anemia. Magnetic resonance imaging (MRI) of the brain revealed hydrocephalus along with multiple intracranial hemangiomas. These lesions compressed the jugular foramina, resulting in venous sinus thrombosis involving the right transverse sinus, the left sigmoid sinus, and the torcular herophili. The patient had no family history of phakomatoses or other genetic abnormalities. A thrombophilia work-up result was unremarkable. The patient was treated with prednisolone (10 mg twice daily) and low molecular weight heparin (1 mg/kg/dose) twice daily. This treatment decreased the size of her cutaneous and intracranial hemangiomas and led to the resolution of her venous sinus thromboses and hydrocephalus. Innocuous scalp hemangioma in an infant may herald more concerning intracranial pathology, which can be treated effectively if diagnosed with appropriate imaging studies.
Abstract: Bone graft volume decreases postoperatively without known etiology. We sought to determine the bone graft volume over time in 15 consecutive patients undergoing a single-level, instrumented, posterolateral lumbar fusion for degeneration causing mechanical pain or spondylolisthesis, and to identify factors associated with bone graft resorption. Following Institutional Review Board approval, a retrospective analysis was performed. Immediate and 3-month postoperative lumbar spine CT scans were imported into imaging software for volumetric analysis. We found that the 15 patients averaged approximately 11% graft volume loss at 3 months postoperatively. All patients exhibited volumetric graft loss on each side (range, 0.3-45%). A paired t-test revealed that immediate postoperative graft volume on a patient's left or right did not reflect graft volume on that side 3 months postoperatively (p=0.0008). Gender, age, history of prior operation, history of regular exercise, body mass index, level fused, operative time, initial graft volume, and laterality did not influence percentage volumetric loss (p=0.1-0.5). Interestingly, people who smoked cigarettes (range, 10-40 pack-years) exhibited 27% graft loss, compared to 7% in those who did not (Spearman p=0.009 graft loss versus pack-years smoked). We concluded that bone graft exhibited resorption 3 months postoperatively on both sides of all patients in this series, and that smoking was significantly associated with increased bone graft resorption.
Abstract: Chondroblastomas are rare tumors that characteristically arise from the epiphyseal cartilage of long bones of the immature skeleton. Intracranial involvement is uncommon, though the squamous portion of the temporal bone is preferentially affected due to its cartilaginous origin. Patients with temporal bone chondroblastomas classically present with otologic symptoms, while primary neurological complaints are rare. In this report, we describe a 33 year-old man with a chondroblastoma of the temporal bone and an associated aneurysmal bone cyst constituting a large intracranial mass lesion who presented with new-onset seizure activity. We review issues relevant to the pathology and treatment of these lesions.
Abstract: Acute encephalitis, encephalopathy, and seizures are known rare neurologic sequelae of respiratory tract infection with seasonal influenza A and B virus, but the neurological complications of the pandemic 2009 swine influenza A (H1N1) virus, particularly in adults, are ill-defined. We document two young adults suffering from H1N1-associated acute respiratory distress syndrome and renal failure who developed cerebral edema. The patients acutely developed a transtentorial brain herniation syndrome including a unilateral third nerve palsy (dilated and unresponsive pupils), elevated intracranial pressure, coma, and radiological evidence of diffuse cerebral edema. In both patients, neurological deterioration occurred in the context of hyponatremia and a systemic inflammatory state. These patients illustrate that severe neurologic complications, including malignant cerebral edema, can occur in adults infected with H1N1 virus, and illustrate the need for close neurological monitoring of potential neurological morbidities in future pandemics.
Abstract: We aimed to identify the initial preliminary experience with flow diverting stents (FDS) for the treatment of intracranial aneurysms (IA). A PubMed search was performed to identify studies reporting patients treated with FDS. Selection was made for studies that provided either immediate or short term follow-up data. For each study, the number of patients and IA were identified. Details regarding the aneurysm itself were recorded; such as aneurysm morphology (saccular or fusiform), location, and rupture status. The primary treatment modality and the number of stents used to treat each aneurysm was recorded along with the antiplatelet regimen used. Outcomes such as aneurysm occlusion and complications, including stroke, in-stent thrombosis and stenosis, and death were identified. The average length of follow-up was calculated in weeks. A total of 10 manuscripts reporting 206 IA in 190 patients were identified in the literature. Occlusion rates were variably reported, ranging from 58% to 94% in the larger series. Major complications of treatment included stroke (6.0%), in-stent thrombosis and stenosis (4.9%), and death (3.3%). A phenomenon of delayed aneurysm rupture was also identified. We concluded that flow diverting stents have proven effective in a variety of scenarios. The major complications with FDS have related to perforator artery stroke, aneurysm re-rupture, and in-stent stenosis and thrombosis. Long-term efficacy, optimal antithrombotic agent regimen, and perforator stroke risk are yet to be determined.
Abstract: Neurocysticercosis is an infection caused by the larvae of the pork tapeworm Taenia solium. Parenchymal lesions commonly present with seizure activity and intraventricular lesions can cause hydrocephalus. A 33-year-old female patient presented in a comatose state with acute hydrocephalus and a fourth ventricle lesion. She underwent placement of an external ventricular drain. Resection of the fourth ventricle lesion through a suboccipital approach allowed for restoration of normal cerebrospinal fluid (CSF) flow and relief of midbrain compression. The lesion was resected intact and the patient returned to normal neurological function. No CSF diversion procedure was necessary. The patient was discharged on cysticidal and steroid therapy. We concluded that surgical resection of lesions in the fourth ventricle attributed to neurocysticercosis is appropriate when brainstem compression is prominent. Resection may also avoid the need for permanent CSF diversion. We also reviewed the evidence-based management strategies described in the literature.
Abstract: To report a new manifestation of the rare connective tissue disorder arterial tortuosity syndrome in the absence of skin and soft-tissue abnormalities and with bilateral, giant fusiform intracranial aneurysms.
Abstract: Cerebral angiography is widely regarded as the gold standard for the evaluation and diagnosis of neurovascular abnormalities. However, recent improvements in the spatial and temporal resolution of time-resolved magnetic resonance angiography (MRA) offer clinicians a non-invasive alternative to cerebral angiography. We explored the utility of this technique in an elderly female patient with a suspected intracranial dural arteriovenous fistula (dAVF). A product pulse sequence available from the scanner's manufacturer (time-resolved imaging of contrast kinetics, TRICKS; GE Healthcare, Milwaukee, WI, USA) was used with the following parameters: TR/TE 2.832/TE 1.072 ms, flip angle 25°, receiver bandwidth 31.25 kHz, 0.75 NEX, acceleration factor (ASSET) of 2, field of view 14 cm, matrix size 96 × 96, phase-encoding left-right. Twenty overlapping 8-mm-thick slices were acquired in an axial orientation, with a slice spacing of 4mm. Images were acquired at 48 time points, with a temporal resolution of 0.3s/image. We found that all intracranial venous structures enhanced synchronously. There was no evidence of arteriovenous shunting. Retrograde venous flow explained the signal abnormality seen on time-of-flight MRA. We concluded that time-resolved MRA is useful in the investigation of suspected intracranial dAVF.
Abstract: Previous methods to determine stroke prevalence, such as nationwide surveys, are labor-intensive endeavors. Recent advances in search engine query analytics have led to a new metric for disease surveillance to evaluate symptomatic phenomenon, such as influenza. The authors hypothesized that the use of search engine query data can determine the prevalence of stroke.
Abstract: Objective To describe the effective treatment of a ruptured lateral sacral artery aneurysm presenting as a spinal epidural hematoma. Design Case report and literature review. Setting University teaching hospital, neurovascular center. Participant A man with a history of renal allograft who presented with sudden onset low back pain. Intervention The patient underwent emergent decompressive surgery, diagnostic angiogram and endovascular embolization. Main outcome measure Obliteration of aneurysm and restoration of neurological function. Results Surgery resulted in decompression of the cauda equina. The patient's aneurysm was endovascularly obliterated. There was complete restoration of neurological function. Conclusion Lateral sacral artery aneurysm formation and rupture is a rare cause of epidural hemorrhage and one described only in patients who have undergone renal transplantation. It may be caused by high flow from transpelvic collaterals between both internal iliac arteries. Treatment includes endovascular obliteration and may necessitate operative decompression in the setting of neurological compromise.
Abstract: Brainstem cavernous malformations (CMs) are complex lesions associated with hemorrhage and neurological deficit. In this review, the authors describe the anatomical nuances relating to the operative techniques for these challenging lesions. The resection of brainstem CMs in properly selected patients has been demonstrated to reduce the risk of rehemorrhage and can be achieved relatively safely in experienced hands.
Abstract: We report a 92-year-old female with ankylosing spondylitis who suffered a non-displaced cervical fracture of the C4 vertebral body as the result of a mechanical fall. A rigid cervical collar was used to maintain stability. The patient later went on to develop upper airway obstruction as a result of fracture displacement. She was emergently intubated for airway protection. To our knowledge, this is the first report of interval, acute onset upper airway obstruction caused by cervical instability following trauma and fracture in a patient with ankylosing spondylitis. This example highlights one of the potential complications of rigid cervical collar immobilization in patients with spinal instability.
Abstract: Intracerebral hemorrhage (ICH) contributes significantly to the morbidity and mortality of patients suffering from acute leukemia. While ICH is often identified in autopsy studies of leukemic patients, it is rare for ICH to be the presenting sign that ultimately leads to the diagnosis of leukemia. We report a patient with previously undiagnosed acute precursor B-cell lymphoblastic leukemia (ALL) who presented with diffuse encephalopathy due to ICH in the setting of an acute blast crisis. The diagnosis of ALL was initially suspected, because of the hyperleukocytosis observed on presentation, then confirmed with a bone marrow biopsy and flow cytometry study of the peripheral blood. Furthermore, detection of the BCR/ABL Philadelphia translocation t(9:22)(q34:q11) in this leukemic patient by fluorescent in situ hybridization permitted targeted therapy of the blast crisis with imatinib (Gleevec). Understanding the underlying etiology of ICH is pivotal in its management. This case demonstrates that the presence of hyperleukocytosis in a patient with intracerebral hemorrhage should raise clinical suspicion for acute leukemia as the cause of the ICH.
Abstract: Vestibular schwannomas (VSs) are rare in the pediatric population. Most often, these lesions manifest as a bilateral disease process in the setting of neurofibromatosis Type 2. Even in the absence of additional clinical diagnostic criteria, the presentation of a unilateral VS in a young patient may be a harbinger of future penetrance for this hereditary tumor syndrome.
Abstract: Chronic paroxysmal hemicrania (CPH) is a rare, unilateral primary headache syndrome. Recent studies suggest hypothalamic dysfunction as the likely cause of CPH. Therapeutic response to deep brain stimulation of the hypothalamus has been observed in the treatment of related trigeminal autonomic cephalgias. We explored the therapeutic effectiveness of posterior hypothalamic stimulation for the treatment of CPH in a patient intolerant of medical management.
