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Ashwini D Sharan

Publications and source records attributed to Ashwini D Sharan.

8 recordsLinked to original sources
PubMed2006

Long-term magnetic resonance imaging evaluation of bioresorbable anterior cervical plate resorption following fusion for degenerative and traumatic disk disruption.

STUDY DESIGN: A retrospective magnetic resonance imaging (MRI) review of a series of patients who underwent a single-level anterior cervical discectomy and fusion followed by anterior plate stabilization using an anterior cervical resorbable mesh plate and screw system. OBJECTIVE: MRI evaluation of the long-term implant resorption properties of a bioresorbable anterior cervical plate and the adjacent peri-implant soft tissue environment. SUMMARY OF BACKGROUND DATA: The use of bioresorbable anterior cervical plates for immediate cervical stabilization following an anterior cervical discectomy and fusion presents several distinct advantages over metallic instrumentation. Bioresorbable polymers may diminish, by their resorbability, implant-related complications such as loosening, migration, and failure of instrumentation, as well as stress shielding of the underlying fusion. Information on the intermediate and long-term bony and soft tissue reaction to the resorption byproducts of these biomaterials is limited. METHODS: There were 9 consecutive patients who underwent single-level anterior cervical decompression and fusion using allograft cortical bone, followed by bioresorbable polylactide anterior mesh plate and screw fixation. Following institutional review board approval, 5 of the 9 patients agreed to postoperative MRI assessment of the peri-implant area. An independent radiologist then characterized implant degradation, and the presence of soft tissue inflammation and swelling during the resorption phase of the bioresorbable plate. RESULTS: At an average follow-up of 32 months, MRI assessment showed no evidence of soft tissue swelling or inflammation related to the resorption of a bioresorbable anterior plate in any of the 5 patients. In addition, none of the patients complained of any dysphagia or phonation difficulties. CONCLUSIONS: Based on MRI assessment, these devices, at more than 2-year follow-up, did not indicate any local chronic inflammation or swelling resulting from their degradation. Clinical symptoms of dysphagia or dysarthria, a common reported problem following anterior cervical spine procedures, were not observed in any patient.

Absorbable Implants↗
PubMed2006

Deep brain stimulation for Parkinson's disease: surgical issues.

Numerous factors need to be taken into account when implanting deep brain stimulation (DBS) systems into patients with Parkinson's disease. The surgical procedure itself can be divided into immediate preoperative, intraoperative, and immediate postoperative phases. Preoperative considerations include medication withdrawal issues, stereotactic equipment choices, imaging modalities, and targeting strategy. Intraoperative considerations focus on methods for physiological confirmation of a given target for DBS electrode deployment. Terms such as microelectrode recording, microstimulation, and macrostimulation will be defined to clarify inconsistencies in the literature. Advantages and disadvantages of each technique will be addressed. Furthermore, operative decisions such as staging, choice of electrode and implantable pulse generator, and methods of device fixation will be outlined. Postoperative issues include imaging considerations, including magnetic resonance safety, device-device interactions, and immediate surgical complications pertaining to the DBS procedure. This report outlines answers to a series of questions developed to address all aspects of the DBS surgical procedure and decision-making with a systematic overview of the literature (until mid-2004) and by the expert opinion of the authors. This is a report from the Consensus on Deep Brain Stimulation for Parkinson's Disease, a project commissioned by the Congress of Neurological Surgeons and the Movement Disorder Society. It outlines answers to a series of questions developed to address all surgical aspects of deep brain stimulation.

Brain↗
PubMed2006

Deep brain stimulation for Parkinson's disease: surgical technique and perioperative management.

Deep brain stimulation (DBS) is a widely accepted therapy for medically refractory Parkinson's disease (PD). Both globus pallidus internus (GPi) and subthalamic nucleus (STN) stimulation are safe and effective in improving the symptoms of PD and reducing dyskinesias. STN DBS is the most commonly performed surgery for PD as compared to GPi DBS. Ventral intermediate nucleus (Vim) DBS is infrequently used as an alternative for tremor predominant PD patients. Patient selection is critical in achieving good outcomes. Differential diagnosis should be emphasized as well as neurological and nonneurological comorbidities. Good response to a levodopa challenge is an important predictor of favorable long-term outcomes. The DBS surgery is typically performed in an awake patient and involves stereotactic frame application, CT/MRI imaging, anatomical targeting, physiological confirmation, and implantation of the DBS lead and pulse generator. Anatomical targeting consists of direct visualization of the target in MR images, formula-derived coordinates based on the anterior and posterior commissures, and reformatted anatomical stereotactic atlases. Physiological verification is achieved most commonly via microelectrode recording followed by implantation of the DBS lead and intraoperative test stimulation to assess benefits and side effects. The various aspects of DBS surgery will be presented.

Antiparkinson Agents↗
PubMed2004

Neurostimulation system used for deep brain stimulation (DBS): MR safety issues and implications of failing to follow safety recommendations.

The use of magnetic resonance imaging (MRI) in patients with neurostimulation systems used for deep brain stimulation requires the utmost care, and no individual should undergo an MR examination in the absence of empirical evidence that the procedure can be performed safely. The risks of performing MRI in patients with neurostimulators include those associated with heating, magnetic field interactions, induced currents, and the functional disruption of these devices. The exact safety recommendations for the particular neurostimulation system with regard to the pulse generator, leads, electrodes, operational conditions for the device, the positioning of these components, and the MR system conditions must be carefully followed for MRI. As highlighted by 2 recent accidents, the failure to strictly follow safety recommendations (eg, use a 1.5-T MR system with a send/receive head radiofrequency coil only; limit the specific absorption rate to 0.4 W/kg; etc.) may result in serious, temporary, or permanent injury to the patient including the possibility of transient dystonia, paralysis, coma, or even death.

Brain Diseases↗
PubMed2004

Tracheostomy placement in patients with complete cervical spinal cord injuries: American Spinal Injury Association Grade A.

OBJECT: The authors sought to identify variables that predispose patients with acute American Spinal Injury Association (ASIA) Grade A cervical spinal cord injury (SCI) to require tracheostomies for ventilator support or airway protection. METHODS: A retrospective analysis was performed of 178 consecutive patients with a cervical ASIA Grade A SCI who were admitted through the Delaware Valley SCI Center at Thomas Jefferson Hospital during a 6-year period. Exclusion criteria included injury occurring more than 48 hours prior to admission, death within 14 days of admission or nontraumatic SCI. Twenty-two patients were excluded based on these criteria. Parameters evaluated in the remaining population (156 patients) included demographics, cervical vertebral ASIA level, tracheostomy placement, pneumonia, premorbid pulmonary disease, smoking history, evidence of direct thoracic/lung trauma, operative intervention, associated appendicular trauma, and preexisting medical comorbidities. The ASIA classification of the 156 patients included in this analysis were C-2 (eight), C-3 (11), C-4 (64), C-5 (36), C-6 (20), C-7 (13), and C-8 (four). Tracheostomies were performed in 107 of these 156 patients. Statistical analysis revealed a significant relationship between tracheostomy and patient age (p = 0.0048), preexisting medical conditions (p = 0.0417), premorbid lung disease (p = 0.0177), higher cervical ASIA level (p < 0.0001), and the presence of pneumonia (p < 0.0001). No patient with a C-8 ASIA A injury required tracheostomy, whereas all C-2 and C-3 ASIA A-injured patients underwent tracheostomies. Patients older than 45 years of age with ASIA A levels between C-4 and C-7 more commonly required tracheostomy (p < 0.005) than patients younger than 45 years of age. CONCLUSIONS: Several risk factors were identified that corresponded to the frequent tracheostomy placement in the acute injury phase after complete cervical SCI. Early tracheostomy may be considered in patients with multiple risk factors to reduce duration of stay in the intensive care unit and facilitate ventilatory weaning.

Adolescent↗
PubMed2003

Precentral stimulation for chronic pain.

A decade of clinical experience has suggested that precentral stimulation is an option for patients with deafferentation as well as other chronic pain syndromes. Permanent complications are uncommon. More scientific evidence is warranted to understand the precise mechanisms for this treatment modality. A larger organized clinical trial is desired to establish the efficacy of precentral stimulation.

Brain↗
PubMed2003

Cervicothoracic radiculopathy treated using posterior cervical foraminotomy/discectomy.

OBJECT: The authors conducted a study to identify the effectiveness and morbidity rate associated with treating cervicothoracic disc disease (radiculopathy) via a posterior approach. METHODS: Nineteen patients underwent posterior cervicothoracic laminoforaminotomy during a 5.6-year period. Medical records, imaging studies, office charts, hospital records, and phone interview data were reviewed. Specific information analyzed included patient demographics, side of lesion, and conservative treatment, symptoms, and pre- and postoperative pain levels. Pain was rated using a visual analog scale and classified into a radicular and neck component. Data in 19 patients (seven women and 12 men) who underwent 20 procedures (one patient underwent separate bilateral foraminotomies) were analyzed. The mean patient age was 54.8 years (range 38-73 years), and the follow-up period ranged from 23 to 62 months. Symptom duration ranged from 1 to 14 months (mean 3.4 months) and consisted of weakness, numbness, and painful radiculopathies in 11, 16, and 20 cases, respectively. Motor weakness was identified in 11 of 19 patients (mean grade of 4.35), and postoperatively strength normalized in eight of 11 (mean grade of 4.79). The improvement in motor scores was significant (p = 0.007). Pain was the most common presenting symptom. Preoperative radiculopathies were rated between 0 and 10 (mean 7.45), and postoperatively scores were reduced to 0 to 3 (mean 0.2) which was significant (p < 0.0001). Preoperative neck pain was rated between 0 and 8 (mean 2.55), and on follow up ranged from 0 to 2 (mean 0.5), which was also significant (p = 0.001). CONCLUSIONS: Posterior cervicothoracic foraminotomy was a safe and effective procedure in the treatment of patients with laterally located disc herniations.

Adult↗