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Ajay Jawahar

Publications and source records attributed to Ajay Jawahar.

At least 19 recordsLinked to original sources
PubMed2005

Assessment of pain control, quality of life, and predictors of success after gamma knife surgery for the treatment of trigeminal neuralgia.

OBJECT: There are various surgical treatment alternatives for trigeminal neuralgia (TN), but there is no single scale that can be used uniformly to assess and compare one type of intervention with the others. In this study the objectives were to determine factors associated with pain control, pain-free survival, residual pain, and recurrence after gamma knife surgery (GKS) treatment for TN, and to correlate the patients' self-reported quality of life (QOL) and satisfaction with the aforementioned factors. METHODS: Between the years 2000 and 2004, the authors treated 81 patients with medically refractory TN by using GKS. Fifty-two patients responded to a questionnaire regarding pain control, activities of daily living, QOL, and patient satisfaction. The median follow-up duration was 16.5 months. Twenty-two patients (42.3%) had complete pain relief, 14 (26.9%) had partial but satisfactory pain relief, and in 16 patients (30.8%) the treatment failed. Seven patients (13.5%) reported a recurrence during the follow-up period, and 25 (48.1%) reported a significant (> 50%) decrease in their pain within the 1st month posttreatment. The mean decrease in the total dose of pain medication was 75%. Patients' self-reported QOL scores improved 90% and the overall patient satisfaction score was 80%. CONCLUSIONS: The authors found that GKS is a minimally invasive and effective procedure that yields a favorable outcome for patients with recurrent or refractory TN. It may also be offered as a first-line surgical modality for any patients with TN who are unsuited or unwilling to undergo microvascular decompression.

Adult↗
PubMed2005

Primary central nervous system lymphoma of the brain stem responding favorably to radiosurgery: a case report and literature review.

OBJECTIVE: To explore various therapeutic alternatives and evaluate the clinical results of patients with primary central nervous system lymphoma (PCNSL). We report a case of PCNSL with involvement of the brain stem managed with radiosurgery using the Leksell gamma knife as the treatment modality. CASE DESCRIPTION: A 55-year-old white woman presented with complaints of weakness on the left side of her body and double vision associated with a frontal headache. Nervous system examination revealed right-sided oculomotor palsy and left-sided motor paresis, grade 2/5, in both upper and lower limbs. Her Karnofsky performance score was 50. A contrast-enhanced magnetic resonance imaging scan of the brain revealed an irregular space-occupying lesion in the pons that enhanced uniformly with gadolinium. A frame-based stereotactic biopsy was performed revealing a B-cell malignant lymphoma. Subsequently, stereotactic radiosurgery using the Leksell gamma knife was performed. A dose of 11 Gy was delivered to the tumor margin. A follow-up magnetic resonance imaging scan after 2 months revealed a 50% reduction in the size of the enhancing lesion. CONCLUSION: Our own results and limited evidence from the literature suggest stereotactic radiosurgery as a potentially safe and effective treatment option in patients with PCNSL.

Brain Stem Neoplasms↗
PubMed2005

Role of stereotactic radiosurgery as a primary treatment option in the management of newly diagnosed multiple (3-6) intracranial metastases.

OBJECTIVE: The objective of this study was to assess the role of stereotactic radiosurgery in the management of newly diagnosed multiple intracranial metastases from known primary cancer locations. METHODS: Fifty (29 women and 21 men) patients received radiosurgery for newly diagnosed 3 or more metastatic brain tumors. Their mean age was 53 years. Lung cancer was the most common primary cancer (66%). RESULTS: Arrest in the growth of irradiated tumors was achieved in 41 (82%) patients. Eight patients (16%) required further intervention for tumors in other brain locations. Mean survival after diagnosis of brain disease was 12 months and the brain disease-controlled period was 19 months. The period of brain disease control prolonged (P=.03) with decreasing tumor volumes (<10 mL). Control of treated tumors positively affected survival after diagnosis of brain disease (P=.0001). CONCLUSION: Radiosurgery as an adjuvant improves survival in patients with cancer who have newly diagnosed multiple intracranial metastases by arresting the growth of tumors.

Adult↗
PubMed2005

Exposure of brain to high-dose, focused gamma rays irradiation produces increase in leukocytes-adhesion and pavementing in small intracerebral blood vessels.

OBJECTIVE: Radiosurgery is used to destroy a predetermined target within the brain, with minimal radiation injury to the surrounding tissue. We hereby present our in vivo model to study the effects of single-session, high-dose radiation on the cerebral vessels that are targeted with radiosurgery using the Leksell Gamma Knife. METHODS: The study was conducted in 29 adult male WT C57BL/6J mice weighing 21 to 28 g (6-8 wk old). The animals were exposed to 100 Gy single-session focused gamma ray irradiation using the Leksell Gamma Knife, and subsequently underwent intravital microscopy at different time intervals to study leukocytes and platelets adhesion patterns to the endothelium of the irradiated cerebral micro-vessels. RESULTS: The leukocyte adhesion response showed a bell-shaped curve upon quantitative analysis with a steady increase in the number of adherent cells during the first four hours and a subsequent plateau response that was maintained during the next 24 hours. The platelet adhesion response did not demonstrate any particular pattern similar to the leukocyte response. CONCLUSION: The experiment was able to establish in vivo increased leukocyte adhesion to the cerebral vascular endothelial cells in response to radiation injury and elaborate the time frame within which the leukocyte adhesion response increases, reaches a peak and then starts decreasing.

Animals↗
PubMed2004

Stereotactic radiosurgery using the Leksell Gamma Knife: current trends and future directives.

Stereotactic radiosurgery is the extremely precise administration of a radiation dosage in three-dimensional space to treat an increasingly broad spectrum of intracranial and skull-base lesions. 455 patients with various indications were treated using the 201 Source Co-60 Leksell Model "B" Gamma Knife(r) at Louisiana State University Health Sciences Center in Shreveport, Louisiana. 273 (60.2%) patients received radiosurgery as the first line of treatment for their disease. The mean Karnofsky Performance Score (KPS) of the patients was 70. Cerebral metastases were the main indications for radiosurgery at our center accounting for 27% of the patients, while meningioma, AVM, trigeminal neuralgia, movement disorders, and primary CNS malignant tumors were the other indications. Our institutional experience and results indicate that low incidence of complications coupled with a high tumor control rate makes Gamma Knife stereotactic radiosurgery a viable option for patients who must undergo neurosurgery. As the Gamma Knife continues to prove itself as a first-line treatment of many complex brain disorders, new indications for this technology will continue to emerge, further broadening the scope of patient care.

Forecasting↗
PubMed2004

Gamma knife radiosurgery for trigeminal neuralgia: a study of predictors of success, efficacy, safety, and outcome at LSUHSC.

BACKGROUND: Trigeminal neuralgia (TN) is a painful condition of controversial origin; however, vascular compression of the root entry zone of the trigeminal nerve is thought to be responsible in some cases. Recently, stereotactic radiosurgery has been established as an alternative treatment for medically intractable TN. METHODS: Forty patients with medically refractory TN underwent gamma knife surgery for pain control at our institution. Dose planning was based on high-resolution, contrast-enhanced, axial, volume acquisition magnetic resonance images. Images were reviewed to detect vascular compression of the trigeminal nerve at the root entry zone by an observer blinded to the affected side and the outcome. Another observer, blinded to radiologic findings, conducted the patient follow-up. Results were classified as excellent and good (favorable outcomes) and failure (unfavorable) based upon the intensity of pain, frequency of episodes, pain medications, and need for additional interventions after radiosurgery. RESULTS: Pain was left-sided in 22 patients and right-sided in 18 patients. Vascular compression of the affected nerve at the root entry zone was demonstrable in 14 patients. Prescription dose ranged from 70 to 90 Gy. At a median follow-up of 14 months (range, 3-31 months), 16 patients (40%) had excellent pain control, 12 (30%) had good control, while 12 (30%) had failed treatment. The Kaplan-Meier actuarial pain control rate at 15 months was 82.25 +/- 0.8% (95%CI). Magnetic resonance detectable vascular compression did not affect the outcome (p = 0.6). Increasing marginal dose (> or =40Gy) was a significant predictor of favorable outcome (p = 0.015). CONCLUSIONS: gamma knife surgery is an effective and safe treatment for TN. In our study, we found that vascular compression of the nerve at the root entry zone was not a predictor of the outcome of gamma surgery for TN. The outcome improves with marginal prescription dose of 80 Gy or higher.

Adult↗
PubMed2004

Survival in relation to radiotherapeutic modality for brain metastasis: whole brain irradiation vs. gamma knife radiosurgery.

The purpose of this report is to evaluate and compare the survival of patients with brain metastasis (BRM) treated by whole brain irradiation (WBI) using linear energy accelerator (LINAC) and by stereotactic radiosurgery using gamma knife. This study consists of a series of 67 patients with BRM treated with WBI between 1998 and 1999 and 53 patients with BRM treated with gamma knife radiosurgery (GKRS) between 2000 and 2001. A retrospective study of the data was performed and the overall survival between these 2 groups was analyzed. The comparability of these 2 groups was tested by chi2 and t test values. Log-rank test was used in the survival comparison. The 1-year survival rate was 26.3% and 22.6%, and corresponding mean survival was 7.8 months and 6.7 months for WBI and GKRS groups, respectively. There was no statistically significant difference between these 2 groups' survival. It was evident from imaging defined lesions that with GKRS the lesions were reduced, stabilized, or disappeared in 89% of cases. Survival of patients with BRM treated with WBI or GKRS was similar in these series. The present study suggests that good tumor response by GKRS does not translate in longer patient survival.

Adult↗
PubMed2004

Management strategies for patients with brain metastases: has radiosurgery made a difference?

BACKGROUND: Brain metastases develop in up to 50% of all patients with cancer. The purpose of this retrospective study was to compare the outcomes for brain metastases patients treated with adjuvant whole-brain radiotherapy (WBRT) or stereotactic radiosurgery (SRS). METHODS: Between 1990 and 1995, 86 patients with brain metastases received external beam WBRT with a megavoltage beam at our center. Between January 2000 and July 2001, 48 patients with 84 tumors diagnosed as cerebral metastases were treated with SRS using the Leksell Gamma Knife. A comparative analysis of the outcomes in the two different groups was made to determine a possible statistically significant difference in survival. RESULTS: In the WBRT group, the median follow-up was 11 months. Thirty-nine patients (45.3%) experienced an improvement in neurologic status. The median overall survival was 5 months (range, 1-40 months). In the SRS group, the median follow-up for this group was 9 months. Thirty-four patients experienced an improvement in their neurologic signs and symptoms. The median survival was 12 months (range, 1-16 months). CONCLUSION: SRS appears to be a safe and effective treatment option for those patients with a limited number of brain metastases and in patients with controlled or limited systemic disease.

Adult↗
PubMed2004

Gamma knife surgery in the management of brain metastases from lung carcinoma: a retrospective analysis of survival, local tumor control, and freedom from new brain metastasis.

OBJECT: The objective of this retrospective study was to analyze the results of stereotactic radiosurgery performed using a gamma knife in the treatment of 44 consecutive patients with brain metastases from lung carcinoma. METHODS: Forty-four patients with lung carcinoma were treated for metastatic brain tumors by performing radiosurgery with a Leksell Gamma Knife. Twenty-one patients (47.7%) were women and 23 were men. The mean age of the patients was 56 years (range 35-77 years). Twenty-two patients (50%) had solitary tumors and the rest had multiple tumors (two-six lesions). Eighteen patients (40.9%) presented with a recurrent and/or progressive brain disease that previously had been treated with other modalities (surgery, external-beam radiotherapy, or both). Fifteen patients had controlled lung disease and 19 patients had systemic metastases (in lymph nodes, liver, and/or bones) at the time of radiosurgery. The median follow-up period was 18.25 months. All patients were followed up for three different end points: 1) death caused by the disease; 2) clinical and/or radiological evidence of progression of the tumor that had been treated with radiosurgery; and 3) appearance of new lesions. At the last follow-up review, 17 patients (38.6%) were alive and 27 (61.4%) had died. Ten patients (22.7%) died as a result of brain disease (failure of local control or new metastases). Controlled primary disease at the time of detection of metastases and the ability to achieve local tumor control after radiosurgery significantly improved the patient survival (p < 0.01). Control of the treated tumor(s) was achieved in 32 of 44 patients (72 tumors) and 10 patients experienced treatment failure. In addition to the 44 patients comprising the study population, two other patients were treated, but died of lung disease too early in the follow-up period to have been assessed. As of the last follow-up review, no new brain metastasis had occurred in 36 patients (81.8% [includes surviving and nonsurviving patients]). The median duration of overall survival was 7 months, the median period of controlled brain disease was 21 months, and the median period of freedom from new brain metastases was 17 months (95% confidence interval 13-19 months). CONCLUSIONS: Gamma knife surgery has significantly reduced the incidence of mortality from brain disease by effectively accomplishing local tumor control in patients with metastatic lung cancer. Local control and freedom from new brain metastases is not influenced by prior external-beam radiotherapy.

Adult↗
PubMed2003

Management of carotid artery injuries: Louisiana State University Shreveport experience.

BACKGROUND: Traumatic carotid artery injury is an infrequently encountered surgical entity. Carotid artery injuries in polytrauma patients can be easily missed in the absence of clinical findings and/or presence of confounding concurrent injuries. METHODS: Between 1991 and 1998, 23 patients were diagnosed with various carotid artery injuries at the trauma center of Louisiana State University Health Sciences Center, Shreveport, Louisiana. Injuries were assessed by angiography and/or surgical exploration of the neck. Clinical presentations, radiologic features, management strategies, and neurologic outcomes were statistically analyzed and compared with the existing literature. RESULTS: Twelve patients (52%) had penetrating carotid artery injuries, while 11 (48%) had blunt trauma. The diagnosis of carotid injury was significantly delayed in the group with blunt trauma as opposed to those with penetrating wounds. Surgical repair was performed in 6 (26%) patients; 2 (8%) underwent balloon occlusion, while ligation was conducted in 2 (8%) patients. Thirteen patients (57%) were treated conservatively with anticoagulants. Six patients (26%) died, while another 6 (26%) had permanent neurologic deficit. Mortality and morbidity was significantly higher in the group with penetrating injuries. A statistical analysis showed that multi-level carotid injury (p < 0.002) and increasing age (p < 0.001) had a significantly higher mortality. CONCLUSIONS: Injury to carotid arteries results in significant mortality and morbidity. Our results indicate that penetrating carotid injury at more than one level carries higher mortality and morbidity rates than blunt injury. Furthermore, early identification of the injured segment may favorably influence the outcome for such patients.

Academic Medical Centers↗
PubMed2003

Multicentric glioblastoma multiforme determined by positron emission tomography: a case report.

UNLABELLED: The actual incidence of true multicentric glioblastoma multiforme (GBM) varies between 2.4 and 4.9% of all GBMs. True multicentric tumors are described as widespread lesions in different lobes or hemispheres, which cannot be explained by spreading along the cerebrospinal fluid or blood pathways. We present here a case of multicentric GBM identified with positron emission tomography. CASE REPORT: A 73-year-old woman with sudden onset headaches, balance problems, and one episode of syncope was diagnosed as having an irregular, contrast-enhancing, space-occupying lesion in the left-temporal-parietal region on magnetic resonance imaging (MRI). The tissue diagnosis was confirmed as GBM, and she received stereotactic radiosurgery using the Leksell Gamma Knife (Elekta Instruments, Atlanta, GA). A 3-month, follow-up, MRI scan showed a remarkable decrease in the size of the contrast-enhancing area that was targeted during radiosurgery. A suspicious area of enhancement was detected on the right side, although no surrounding edema was evident. Fluorodeoxyglucose (FDG)-PET scanning revealed a large irregular neoplasm extending from the inferior left-temporal lobe into the deep parietal lobe with extremely intense FDG uptake, suggesting a very aggressive tumor. A smaller lesion was also discovered in the deep right-frontal lobe, representing a second neoplastic focus. The patient refused any further treatment. CONCLUSION: PET scans, in conjunction with MRI scans, allow for the best possible and most comprehensive diagnosis and treatment plans.

Aged↗
PubMed2003

Microsurgery for Potential Radiosurgical Skull Base Lesions: A Retrospective Analysis and Comparison of Results.

The outcomes of 26 complex skull base tumors treated with microsurgery were compared with the outcomes of similar tumors treated with radiosurgery as reported in the literature. The University neurosurgery database was searched for patients who underwent microsurgery for the treatment of skull base tumors between 1990 and 2001 at Louisiana State University Health Sciences Center in Shreveport, Louisiana. Twenty-six skull base meningiomas treated by microsurgery by the senior author (AN) were identified retrospectively. On imaging, the tumors were well defined and less than 3 cm in the greatest diameter, making them ideal candidates for a radiosurgical procedure had this modality been available. The follow-up and outcomes of these 26 patients were compared with the published outcomes of similar tumors treated with radiosurgery. Total excision was achieved in 17 (65.3 %) patients. Excision was subtotal in 9 (34.6 %) patients due to the critical locations of their tumors. The median hospital stay for these patients was 4 days (range, 3 to 12 days). Two patients (7.6 %) had transient cerebrospinal fluid leaks from the wound, and 2 (7.6 %) had transient facial paresis. Overall, preoperative symptoms improved in 23 (88.4 %) patients. The median follow-up was 56 months (range, 3 to 120 months). The overall survival rate for all was 87.2 +/- 3.7 % at 50 months. Two patients (7.6 %) subsequently underwent repeat surgery for a recurrent or progressive disease. The actuarial 8-year tumor control rate was 86.4 +/- 4.4 % using the Kaplan-Meier method. For small skull base tumors with benign histology, microsurgery is as safe and effective a treatment option as stereotactic radiosurgery. The symptomatic improvement in patients is better with microsurgery than with radiosurgery because the volume of the tumor is reduced immediately. A combined approach using both modalities is usually needed for larger tumors when attempts at total resection would jeopardize the neurologic function of the patient.

Journal Article↗
PubMed2003

Gamma knife irradiation increases cerebral endothelial expression of intercellular adhesion molecule 1 and E-selectin.

OBJECTIVE: Alterations in multiple functions of the microvasculature occur in response to gamma irradiation and are thought to contribute to radiation-induced end organ damage by inducing inflammatory responses, particularly leukocyte infiltration into the affected area. Endothelial cell adhesion molecules (ECAMs) mediate leukocyte adhesion and migration. Here, we validate a method to study the effect of Leksell gamma knife stereotactic radiosurgery on the expression of ECAMs on human cerebral endothelium at 0, 24, 48, and 72 hours after irradiation. METHODS: A human brain endothelial cell line (IHEC) was cultured on 12-mm coverslips and subjected to 50 Gy of collimated gamma irradiation with the Leksell gamma knife (Elekta Instruments, Inc., Atlanta, GA). Lactate dehydrogenase release was measured at 24, 48, and 72 hours after irradiation and caspase-3 at 24, 48, 72, 96, and 120 hours. ECAM expression was measured at postirradiation intervals of 0, 24, 48, and 72 hours by cell enzyme-linked immunoabsorbent assay. We used a cell irradiator composed of two chambers. The upper chamber holds the coverslips firmly in place while they are immersed in media. The lower chamber is connected to a peristaltic pump, which pumps water into the chamber and maintains the media in the upper chamber at 37 degrees C through convection. RESULTS: None of the ECAMs tested was significantly elevated compared with the control basally. Twenty-four hours after irradiation, intercellular adhesion molecule 1 was significantly elevated on brain endothelial cells but there was no significant elevation of E-selectin. Vascular cell adhesion molecule 1 was increased slightly but not significantly and decreased at 48 hours. At 72 hours, E-selectin expression was significantly increased; intercellular adhesion molecule 1 and vascular cell adhesion molecule 1 were not altered relative to sham controls. CONCLUSION: Increased ECAM expression and lactate dehydrogenase release support the idea that the cerebral microvasculature undergoes an inflammatory response after Leksell gamma knife stereotactic radiosurgery.

Apoptosis↗
PubMed2002

Commentary.

Explore the source record for details and available documents.

Journal Article↗
PubMed2002

Gamma knife radiosurgery for brain metastases: do patients benefit from adjuvant external-beam radiotherapy? An 18-month comparative analysis.

OBJECTIVE: To analyze 18 months of results of gamma knife stereotactic radiosurgery in the treatment of brain metastases and determine factors affecting outcome by examining the effectiveness of additional external-beam radiotherapy (XRT). MATERIALS AND METHODS: Between January 2000 and September 2001, 61 patients with 103 tumors diagnosed as cerebral metastases were treated with gamma knife. Mean patient age was 57 years (range = 36-81). Lung carcinoma (55.7%) was the most common primary cancer, followed by melanoma (14.8%) and breast carcinoma (11.5%). Mean KPS of the patients was 70 (range = 50-90). Twenty-seven patients had solitary metastases while 34 had multiple tumors. Forty-three patients (59 tumors in total) received only radiosurgery, while 18 patients (44 tumors in total) had prior XRT. Tumor volume ranged from 0.5 to 33 cm(3) (mean = 9.74 cm(3)). Mean marginal dose prescription to the tumor was 15 Gy (range = 11-21 Gy). RESULTS: Median follow-up was 11 months. Twenty-one patients (34.4%) were alive at last follow-up and 40 (65.6%) had died. Seventeen deaths (42.5%) were reported to be due to progressive brain disease, while 23 deaths (57.5%) were due to uncontrolled primary. Control of the treated lesions was achieved in 45 patients (73.8%) and 84 tumors (81.6%). Mean overall survival of the patients is 8 months (range = 1-19 months). The actuarial 12-month tumor control rate using the Kaplan-Meier method for this series is 68.2 +/- 0.06%. Results of the log-rank test revealed that younger age (<55 years), small tumor volume (<10 cm(3)), and increasing tumor dose (>15 Gy) correlated with improved brain disease-free survival (p < 0.05). Overall survival, local tumor control rate and the freedom from brain disease period (based on the appearance of new brain tumors after radiosurgery) were analyzed separately for the groups receiving radiosurgery alone and those with prior XRT to detect any additional benefit of XRT. No statistically significant difference was found between the two groups for any of the considered outcomes. CONCLUSION: Gamma knife stereotactic radiosurgery is a safe and effective treatment option for patients with cerebral metastases. It provides survival benefits and improves quality of life by achieving excellent control of the brain disease, irrespective of patients' age or number of brain tumors. The addition of XRT in younger patients with small brain metastases does not improve survival and/or control of the brain disease.

Adult↗
PubMedDate not supplied

First 100 cases of gamma knife radiosurgery in Louisiana: analysis of demographics and early results.

Louisiana's first ever Leksell Gamma Knife was commissioned at Louisiana State University Health Sciences Center (LSUHSC) in Shreveport in January 2000. Between January 2000 and January 2001,113 patients with various indications were treated using the 201-source Co-60 Leksell model "B" Gamma Knife (Elekta Instruments, Atlanta, Georgia) at LSUHSC-Shreveport. Sixty-three patients were female and 50 were male. The patient age ranged between 13 and 87 years (mean age = 57 years). Fifty-eight (51.3%) patients received radiosurgery as the first line of treatment for their disease, while 55 (48.7%) had previous operations or radiation therapy. The median Karnofsky Performance Score of the patients was 80 (range = 70 to 100). Cerebral metastases were the main indication for radiosurgery at our center accounting for 35% of the patients, while meningioma, arteriovenous malformation, trigeminal neuralgia, and primary central nervous system malignant tumors were the other indications.

Adolescent↗
PubMedDate not supplied

Management of epidural cauda equina disease of prostate cancer by radiotherapy.

OBJECTIVE: Secondary prostate cancer affection of the cauda equina (SPCCE) can be an ultimate cause of morbidity and mortality. Since the results of management of this particular disease condition remain largely unknown, a retrospective case review was undertaken to determine the effects of treatment by radiation in SPCCE patients. METHODS: The records of 12 patients with SPCCE treated at the Division of Therapeutic Radiology during the period 1984 to 1998 were reviewed. The administered total radiation dosage ranged from 6 Gy to 32 Gy (average, 26.6 +/- 2.0 Gy). Two individuals underwent decompressive laminectomy and bilateral orchiectomy at the time of SPCCE and prostate cancer diagnoses. Ten patients had prior hormonal manipulative treatment (orchiectomy, estrogen, or Flutamide therapy). RESULTS: Pain was relieved in three of four symptomatic patients (75%). Five of nine patients unable to walk before therapy could walk after treatment. One of two individuals with anal or bladder sphincter dysfunction improved following irradiation. The overall mean duration of survival was five months. With treatment, survival was approximately three times as long for ambulatory versus non-ambulatory patients. CONCLUSION: We conclude that radiation treatment is efficacious in promoting palliation of SPCCE, although it may not prolong life.

Aged↗