Biomedical subjects

Henry E Aryan

Publications and source records attributed to Henry E Aryan.

At least 19 recordsLinked to original sources

PubMed2005

Complications of interhemispheric transcallosal approach in children: review of 15 years experience.

OBJECTIVE: The interhemispheric transcallosal approach to deep-seated lesions in and around the ventricular system avoids cortical manipulation and injury. Few case series discuss the morbidity associated with this approach. This study describes the 15-year experience of the senior author in Southern California. METHODS: All pediatric patients who have undergone interhemispheric, transcallosal resections of mass lesions over a 15-year period were identified. The surgical approach was uniform with respect to positioning of the patient. Intra-operative and post-operative data were collected retrospectively from the medical records. The need for bridging vein ligation as well as the incidence of hemiparesis, seizures, memory disturbances, and the need for subsequent cerebrospinal fluid (CSF) diversion were identified. RESULTS: Sixty-five patients were identified. The incidence of transient post-operative hemiparesis appeared to be higher in those patients who required ligation of one or two parasagittal veins (44.6% versus 18.5%) with no difference in long-term outcome. Nineteen percent (18.5%) of patients had post-operative seizures; however, no long-term seizure disorder was identified. Nine percent (9.2%) had reports of transient short-term memory deficits. Thirty-four percent (33.8%) of patients required secondary operative intervention for CSF diversion. The total complication rate, including need for CSF diversion, transient hemiparesis, infection, post-operative seizures, and memory disturbance was 36.9%. By 1 year, the total number of patients with persistent hemiparesis, memory disturbance, or seizures refractory to medication was 4 (6.2%). CONCLUSION: This series demonstrates that the interhemispheric transcallosal corridor is a versatile and safe approach in childhood, resulting in low post-operative permanent morbidity.

Adolescent↗

PubMed2005

Intradural cranial congenital dermal sinuses: diagnosis and management.

OBJECTIVE: The congenital dermal sinus (CDS) is a benign tumor-like entity that has unique anatomical and clinical features. We retrospectively examined our data to determine factors associated with adverse outcomes for cranial-based dermal sinuses. METHODS: We retrospectively examined our data obtained from patients presenting between 1975 and 2002. Sixty-seven patients with a CDS were found. Of these, 20 cases of a cranial CDS were identified, 15 of which had evidence of an intradural component. RESULTS: Surgical treatment of congenital dermal sinuses was accompanied with, in general, excellent results. Poor outcomes were most strongly associated with delays in diagnosis. The most common complications were infection at the surgical site (five patients) and hydrocephalus necessitating ventriculoperitoneal shunt placement (two patients). Permanent neurological deficits were rare. CONCLUSION: Cranial CDSs are unusual lesions found in children. A majority of these lesions may penetrate the dura and lead to significant complications if not promptly identified and treated in an appropriate and timely fashion.

Child↗

PubMed2005

Subfrontal transbasal approach and technique for resection of craniopharyngioma.

A multimodality approach to craniopharyngioma, including minimally invasive stereotactic techniques, microsurgery, conventional radiotherapy, and radiosurgery has been recommended to tackle craniopharyngioma aggressively while minimizing harm to the patient. With all approaches, there are varying levels of risk for endocrinological morbidity, vascular complications, neuropsychological and behavioral disorders, neurocognitive disorders, and learning disabilities. Although many treatment options are available, total tumor resection remains the most commonly performed procedure for treatment of craniopharyngioma, and it is still believed to give the patient the greatest chance of having an independent and productive life with low risk of recurrences. The authors prefer the subfrontal transbasal approach for resection of these tumors, and they describe this approach and illustrate it with the accompanying figures.

Brain Neoplasms↗

PubMed2005

Kyphoplasty-augmented short-segment pedicle screw fixation of traumatic lumbar burst fractures: initial clinical experience and literature review.

OBJECT: Surgical intervention for thoracolumbar burst fractures is indicated for patients with neurological deficits and/or evidence of severe spinal instability. The goals of surgery are decompression, deformity correction, and stabilization. Nevertheless, the optimal surgical strategy to achieve these goals remains a subject of debate. Short-segment pedicle screw fixation is associated with a 20 to 50% incidence of pedicle screw failure and progressive spinal deformity. Initial biomechanical and clinical studies have shown that reinforcement of short-segment pedicle screw fixation with vertebroplasty improves spinal stability and decreases instrument failure rates. In this study, the authors describe their initial clinical experience with kyphoplasty used to augment short-segment pedicle screw fixation of traumatic lumbar burst fractures. METHODS: Five patients with traumatic burst fractures of the lumbar spine were included in this retrospective review of patients treated for this disorder at the University of California, San Diego and the University of California, San Francisco between 2002 and 2004. All patients underwent transpedicular kyphoplasty and short-segment pedicle screw fixation. The mean follow-up period was 10.6 months (range 6-18 months). All patients underwent short-segment pedicle screw fixation reinforced with polymethyl methacrylate kyphoplasty. The preoperative, postoperative, and follow-up plain x-ray films were evaluated. Radiographic analysis included measurements of kyphotic angulation, anterior vertebral body height, and evidence of bone fusion. Clinical evaluation was performed postoperatively and at follow-up review. CONCLUSIONS: Based on the authors' initial experience, kyphoplasty supplementation may improve the long-term integrity of short-segment pedicle screw constructs and allow for improved rates of fusion and better clinical outcomes in patients with traumatic lumbar burst fractures.

Adult↗

PubMed2005

Surgical correction of metopic synostosis.

BACKGROUND: Premature closure of the metopic suture results in deformation of the anterior portion of the calvarium, which can vary from mild to severe. In mild forms, there is only prominent ridging of the metopic suture; more severe forms result in a marked narrowing of the frontal and temporal regions that in turn affects the supraorbital rims and produces hypotelorism. METHODS: The authors retrospectively reviewed 39 consecutive cases of metopic synostosis treated over a 12-year period. RESULTS: The average age at referral was 5 months, with surgery performed at an average age of 7.5 months. Fifteen infants had other congenital anomalies, with eight having synostosis of other sutures. Follow-up ranged from 7 months to 6 years, with an average of 29 months. In three mild cases, burring of the metopic ridge was performed with excellent aesthetic results in all cases. The other 36 patients had significant deformity of the supraorbital ridges and temporal regions, with obvious hypotelorism for over 50% of the time. In these cases, the patients underwent craniofacial reconstruction to normalize their appearance. In addition, the lateral aspect of the sphenoid ridges, including the orbital roof and lateral orbital wall to the infraorbital fissure, was removed to free the cranial base. The average blood loss was under 400 ml and the average hospital stay was 3.6 days. Results were considered good to excellent in all except three cases, which had recurrence of a prominent metopic ridge; two required a second operation after 6 months for burring of this ridge, whereas the third was treated conservatively with an orthotic headband. CONCLUSION: Mild forms of metopic synostosis can be successfully treated with burring of the metopic ridge alone. Severe forms require craniofacial reconstruction and may be associated with other congenital abnormalities, additional synostosis, and developmental delay. In all cases, the operative procedure must be tailored to the nature and severity of the deformity.

Child↗

PubMed2005

Thymoma metastatic to the extradural spine.

BACKGROUND: Spinal epidural metastases are the most common spinal tumor, occurring in 10% of cancer patients. Malignant thymoma is a mediastinal tumor, with extrathoracic metastases occurring in 15% of patients to liver, kidney, and bone. Spinal metastasis is exceptionally rare. We present a case of thymoma with extradural metastasis and discuss the relevant literature. CASE REPORT: We describe a 45-year old man presenting with back pain and hypoesthesia twelve years after a diagnosis of thymoma. A review of the literature reveals few cases of thymoma metastatic to the extradural spine. We describe a novel surgical approach allowing ventral spinal cord decompression through a posterior incision. CONCLUSION: Spinal epidural metastases should be suspected in all cancer patients with back pain. Early detection of epidural metastases may enable improved pain control and preservation of spinal stability, ambulation and sphincter control.

Epidural Neoplasms↗

PubMed2005

Microsurgical keyhole middle fossa arachnoid cyst fenestration.

Microsurgical keyhole fenestration is a safe and effective surgical procedure for the treatment of middle fossa arachnoid cysts. This procedure can be performed with minimal morbidity through a keyhole craniotomy. Patient selection is crucial, as is knowledge of the surgical anatomy. We provide a detailed description of the technique, with Illustrations of the key aspects of the procedure.

Arachnoid Cysts↗

PubMed2005

Retinal hemorrhage and pediatric brain injury: etiology and review of the literature.

Retinal hemorrhages have long been linked with child abuse and, in particular, the "shaken baby/shaking-impact" syndrome. However, the presence of retinal hemorrhages is neither necessary nor sufficient for the diagnosis of child abuse. Additionally, retinal hemorrhages are also associated with an ever-expanding list of conditions, each of which carries important implications for patients and their families. To correctly interpret a patient's retinal hemorrhages, the physician requires a broad knowledge base, including of child abuse, the "shaken baby/shaking-impact" syndrome, the differential diagnosis of retinal hemorrhages and the types of retinal hemorrhage and their diagnostic implications. We review the literature regarding types of retinal hemorrhage and their associated etiologies.

Accidents, Traffic↗

PubMed2005

The Charité Artificial Disc: insertion technique.

The Charité Artificial Disc is the first commercially available motion-preserving technology for the lumbar spine. The Charité is the first US Food and Drug Administration-approved artificial disc for the treatment of single-level lumbar degenerative disc disease from L4 to S1. With thousands of implantations worldwide since 1987, it has the longest clinical experience of any artificial disc. No other artificial disc has the substantial preclinical and clinical history that validates its use.

Arthroplasty, Replacement↗

PubMed2005

Emerging directions in motion preservation spinal surgery.

In this review, we focus on novel surgical techniques and spinal arthroplasty systems inactive development. First, we discuss systems that allow for minimally invasive approaches to the lumbar disc space: (1) lateral approaches, (2) posterior approaches,and (3) oblique approaches. These techniques offer the potential for a minimally invasive lumbar arthroplasty system. Second, we discuss novel facet replacement technology. The facet joints, with the intervertebral disc, comprise the three-joint complex of the spinal unit. Facet joint health is thus crucial to proper disc biomechanics and function. Finally,we discuss dynamic neutralization of the lumbar spine with an artificial posterior tension band device. This allows for a certain degree of immobilization without fusion. Minimally invasive surgical approaches, facet arthroplasty, and posterior tension band devices may be the future of motion preservation spinal surgery.

Arthroplasty↗

PubMed2005

The ProDisc artificial disc: insertion technique.

The ProDisc artificial lumbar disc was designed for use in treatment of degenerative lumbar disease. The disc is implanted using an anterior approach to the lumbar spine with the assistance of intraoperative fluoroscopy. A variety of insertion instruments guide the surgeon through this process. The disc is implanted via an anterior approach, generally retroperitoneally but on occasion transperitoneally. The different approaches and insertion technique are described in this article.

Arthroplasty, Replacement↗

PubMed2005

Gunshot wounds to the spine in adolescents.

OBJECTIVE: The incidence of spinal instability after penetrating gunshot wounds to the spine in adolescents is unknown. We describe our experience over a 15-year period. METHODS: Hospital records were reviewed retrospectively. After injury and emergency care, patients were transferred to a rehabilitation facility. Examinations were completed using the American Spinal Injury Association and Frankel scales on admission, discharge, and 6 and 12 months after injury. Severity of injury was described by: 1) degree of neurological damage, 2) degree of preserved neurological function, and 3) presence of instability. RESULTS: Sixty patients were identified with a mean age 15.6 years (+/- 2.7 yr). Twelve patients had cervical, 31 thoracic, and 17 lumbosacral injuries. No operative treatments were used in their care. Thirty-four patients had complete neurological deficits. Mean acute hospitalization was 21.1 days (+/- 22.8 d), and mean rehabilitation stay was 86.3 days (+/- 48.9 d), for a total hospitalization of 107.4 days (+/- 65.9 d). At 1 year, 19 patients were ambulatory and 53 were autonomous. Despite the presence of bony involvement in all, no evidence of spinal instability was noted on follow-up dynamic imaging. Even in two patients with apparent two-column disruption, no instability was noted. At 1-year follow-up, significant (nonfunctional) improvement was noted in the neurological examination (P < 0.0001). Improvements were most notable in those patients with cervical injuries, followed by thoracic and lumbar injuries. CONCLUSION: After penetrating gunshot wounds to the spine, patients at 1-year follow-up examinations have evidence of significant, but nonfunctional, improvement. No evidence of spinal instability was noted in this study, and no surgical intervention was required.

Adolescent↗

PubMed2005

Gel-based surgical preparation resulting in an operating room fire during a neurosurgical procedure: case report.

Despite general reports of fires in the operating room, those during neurosurgical procedures are rare. The most significant contributor to perioperative fires is excess oxygenation. The consideration of novel gel-based surgical preparation solutions as potential fuel sources should be included in the literature. Given the significant patient risk and legal ramifications of surgical fires, education regarding operating room fires and the potential for prevention and treatment is requisite. The authors describe the case of an 18-month-old girl who, while undergoing a resection of a right retroauricular scalp mass, suffered partial thickness bums as a result of the ignition of surgical preparation solution following the use of monopolar electrocautery.

Administration, Topical↗

PubMed2004

Initial experience with antibiotic-impregnated silicone catheters for shunting of cerebrospinal fluid in children.

INTRODUCTION: Infection is a major complication of cerebrospinal fluid (CSF) shunting procedures. Recently, rifampin-impregnated and clindamycin-impregnated silicone catheters have been developed in an attempt to prevent and/or reduce the incidence of shunt infections. In vitro and in vivo animal studies have shown their efficacy in reducing bacterial colonization of catheters. However, these shunts are yet to be evaluated in clinical trials and their safety and efficacy in preventing shunt infections is unknown. METHODS: Between April 2002 and April 2003, 31 children (age range 6 months to 17 years, mean 4.5 years) underwent implantation of an antibiotic-impregnated silicone catheter for CSF diversion. All surgeries were performed by a single neurosurgeon (HSM) at a single medical center. The Codman Hakim Bactiseal silicone catheter was used in all children. Thirty-two catheters were implanted in 31 children. All children have been followed since surgery (for an average of 19 months). For comparison, the previous 46 standard implanted shunts over a similar period of time were reviewed (average follow-up 31 months). RESULTS: Of the 32 implanted catheters, 11 involved placement of a new complete shunt system, 8 were distal revisions, and 13 were proximal/ventricular revisions. There were fewer early and late complications than in the standard shunt group (12.5 and 18.8% vs. 23.9 and 34.8%). There was no local reaction from implantation of the catheters. One child contaminated his distal catheter by disrupting his abdominal incision. None of the other patients have developed any evidence of shunt infection to date. CONCLUSION: Rifampin-impregnated and clindamycin-impregnated silicone catheters appear to be safe and well tolerated in children. Preliminary results suggest a low incidence of shunt infection. Longer follow-up and a larger number of patients are needed to more accurately assess the efficacy of these catheters compared with traditional silicone catheters.

Adolescent↗

PubMed2004

Management of pilocytic astrocytoma with diffuse leptomeningeal spread: two cases and review of the literature.

INTRODUCTION: Leptomeningeal dissemination of juvenile pilocytic astrocytoma (JPA) is a rare event. We report two children with disseminated JPAs treated with a chemotherapeutic agent, temozolomide, after progression of the disease despite surgery, traditional chemotherapy, and/or radiation therapy. CASE REPORTS: Patient 1 presented with hydrocephalus and progressive lower extremity weakness, and was found to have a suprasellar mass as well as extensive spinal disease. Ventriculoperitoneal shunting, decompressive laminectomy with spinal tumor debulking, and chemotherapy with carboplatin and vincristine were initially employed. However, disease progressed and craniospinal irradiation and temozolomide were used. Patient 1 remains in a fair condition today, 2 years later. Patient 2 presented at 8 months of age with failure to thrive. Imaging revealed a cystic lesion in the hypothalamic region with extensive subarachnoid metastatic disease to the spine. Biopsy was performed followed by chemotherapy with vincristine, cyclohexylchloroethylnitrosourea (CCNU), 6-TG, and procarbazine. Due to the continued progression of the disease, cytoreductive surgery was performed and her chemotherapeutic regimen was switched to temozolomide. Two years after initial presentation patient 2 is clinically much improved with stable residual disease. DISCUSSION: We review the literature and discuss treatment strategies for this challenging disease.

Antineoplastic Agents, Alkylating↗

PubMed2004

Primary anaplastic glio-neuronal tumor of the pineal gland: a new type of pineal neoplasm?

BACKGROUND: Tumors of the pineal gland are relatively rare. Most are solid, infiltrative lesions characterized by either germ cell, glial, or pineal parenchymal origin. To our knowledge, none have been described that contain an admixture of both anaplastic glial and neuronal elements. CASE REPORT: The authors present a case of a primary anaplastic glio-neuronal tumor of the pineal gland in a 78-year-old gentleman who presented with hydrocephalus. The patient underwent an endoscopic third ventriculostomy for treatment of his hydrocephalus as well as tumor biopsy under endoscopic visualization. RESULTS: Sections of the tumor displayed a modestly to moderately cellular neoplasm infiltrating the residual pineal gland. The majority of the nuclei appeared hyperchromatic, spindle-shaped, and pleomorphic, with fibrillary cytoplasmic processes. Rare nuclei were round with vesicular chromatin and red nucleoli. Mitotic figures were easily identified, despite small sample size. GFAP immunostaining highlighted the fibrillar background and cytoplasmic processes while synaptophysin immunostains revealed intense, dot-like positivity in the rounder nuclei with vesicular chromatin. Although the different nuclear morphologies seen on the hematoxylin-eosin stained slides suggested both glial and neuronal origin, immunostains were required to confirm the presence of dual differentiation. CONCLUSION: We present the first case of a primary anaplastic glio-neuronal neoplasm of the pineal gland. Increased use of immunostaining may unveil additional cases in the future. Furthermore, additional research will be required to determine whether the dual differentiation has prognostic significance.

Aged↗

PubMed2004

Cerebello-Pontine angle (CPA) lymphoma with perineural extension into the middle fossa: case report.

BACKGROUND: Tumors of the cerebello-pontine angle are most commonly schwannoma and meningioma. Primary central nervous system (CNS) lymphoma usually presents deep within the cerebral hemispheres, occasionally is found in the cerebellum, and rarely occurs in the cerebello-pontine angle. We report a rare case of primary CNS lymphoma involving the right cerebello-pontine angle and the middle cranial fossa mimicking a tentorial meningioma. METHODS: A 21-year-old woman presented with right sided hearing loss and a facial droop. Computed tomography (CT) and magnetic resonance imaging (MRI) were performed, followed by cerebral angiography to assess vascularity. RESULTS: Imaging revealed a bilobed mass involving the right cerebello-pontine angle and middle fossa. The labyrinthine segment of the facial nerve canal was enlarged, and some bony erosion was seen along the petrous bone anteriorly. The mass was hypointense on both T1 and T2-weighted MRI and exhibited heterogenous enhancement. It was distinctly hypovascular on angiography. At surgery, a B-cell lymphoblastic lymphona was found that infiltrated along the 7(th) and 8(th) nerve complexes into the internal auditory canal. CONCLUSION: Imaging and surgery disclosed a cerebello-pontine lymphoma with perineural extension along the 7(th) nerve to reach the middle cranial fossa. Because of the unusual imaging characteristics of this tumor, as well as special considerations with respect to treatment, preoperative consideration of this entity is important in planning direct surgical biopsy rather than an extensive resection.

Adult↗

PubMed2004

Intramedullary spinal cord metastasis of lung adenocarcinoma presenting as Brown-Sequard syndrome.

BACKGROUND: It is extremely rare for cancer to present first as an intramedullary spinal cord metastasis. Furthermore, because it is unlikely for spinal cord neoplasm to present acutely, an acute presentation may signify metastatic disease and should be considered in the initial differential diagnosis. METHODS: The authors present a case of a 59-year-old man presenting with Brown-Sequard syndrome and in whom metastatic lung adenocarcinoma to the spinal cord was subsequently discovered. Review of the literature reveals this case to be one of only a very few where intramedullary tumor was the first manifestation of metastatic disease. RESULTS: The mainstay of treatment for intramedullary spinal metastases remains steroids, radiation, and chemotherapy, though no well-designed study compares these modalities by long-term survival and functional results. This patient underwent local radiation and systemic chemotherapy following surgical resection. CONCLUSIONS: This patient had no preoperative signs suggesting disease in other organs, making the diagnosis of lung adenocarcinoma metastatic to the intramedullary cord surprising, especially given the extremely rare incidence of spinal intramedullary metastatic disease. However, the patient had an acute presentation, uncommon for primary neoplasm, which may be an indication of metastatic disease.

Adenocarcinoma↗