bluuebunny/crossref_metadata_2025_split huggingface dataset:
Postoperative Gamma Knife surgery for benign meningiomas of the cranial base
Authors: Davidson Laurence , Fishback Dawn , Russin Jonathan J. , Weiss Martin H. , Yu Cheng , Pagnini Paul G. , Zelman Vladimir , Apuzzo Michael L. J. , Giannotta Steven L. 
Published: December 2007

Object
The standard treatment for meningiomas is complete resection, but the proximity of skull base meningiomas to important neurovascular structures makes complete excision of the lesion difficult or impossible. The authors analyzed the mid- and long-term results obtained in patients treated with postresection Gamma Knife surgery (GKS) for residual or recurrent benign meningiomas of the cranial base.

Methods
Thirty-six patients with residual or recurrent benign meningiomas of the skull base following one or more surgical procedures underwent GKS. There were 31 women and five men, ranging in age from 22 to 73 years. The median tumor volume was 4.1 ml (range 0.8–20 ml) and the median radiation dose to the tumor margin was 16 Gy (range 15–16 Gy).

Results
Patients were followed for a median of 81 months (range 30–141 months) after GKS. At the end of the follow-up period, overall neurological improvement was observed in 16 patients (44.4%), whereas the condition in 20 patients (55.6%) was unchanged. One patient suffered transient cerebral edema 6 months after GKS. Based on imaging documentation, a partial response was seen in five patients (13.9%), the disease remained stable in 30 patients (83.3%), and in one patient (2.8%) there was an increase in tumor size. The actuarial progression-free survival rate was 100% at 5 years and 94.7% at 10 years.

Conclusions
Gamma Knife surgery was shown to be an excellent adjunct to resection because of its durable rate of tumor control and low toxicity. It should be initially considered along with surgery for the treatment of complex skull base meningiomas.
Nelfinavir potentiation of imatinib cytotoxicity in meningioma cells via survivin inhibition
Authors: Gupta Vinay , Samuleson Christian G. , Su Susan , Chen Thomas C. 
Published: December 2007

✓ Although most meningiomas are treated surgically, it may not be possible to completely remove atypical, malignant, and surgically inaccessible meningiomas; in the majority of these cases there is tumor recurrence. The authors have already reported initial preclinical results on the efficacy of imatinib in the treatment of meningiomas; however, a recent Phase II trial of imatinib in patients with recurrent meningiomas did not demonstrate significant antitumor activity. To enhance the activity of imatinib, the authors investigated the use of a combination therapy with nelfinavir on primary meningioma cells and meningioma cell lines IOMM-Lee and CH157.
Cytotoxicity was measured using methylthiotetrazole and colony formation assays. In low-dose combination therapy with imatinib, nelfinavir potentiated the antiproliferative and anti–colony formation effects of imatinib. Primary meningioma cells responded better to combination therapy than to imatinib alone. Treatment induced a dose-dependent antiproliferative effect, decreased cell survival, and inhibited colony formation. Western blotting demonstrated decreased levels of survivin protein on combination therapy. Because meningiomas have very high levels of survivin protein, survivin inhibition by nelfinavir may represent a potential mechanism for the additive effect observed with imatinib. Moreover, an increase in the proapoptotic Bax/Bcl-2 protein ratio was demonstrated with the combination of imatinib and nelfinavir.
The authors propose that nelfinavir not only potentiates imatinib efficacy, it also abrogates resistance to imatinib by decreasing survivin protein levels in meningiomas. In an in vivo assay, this combination therapy was found to be more effective than imatinib alone. More preclinical work with in vivo models is needed to determine if this new combination therapy will translate into a viable future therapy for meningiomas.
Neuroophthalmological evaluation after Gamma Knife surgery for cavernous sinus meningiomas
Authors: Franzin Alberto , Vimercati Alberto , Medone Marzia , Serra Carlo , Marzoli Stefania Bianchi , Forti Maddalena , Gioia Lorenzo , Valle Micol , Picozzi Piero 
Published: December 2007

Object
Treatment options for patients with cavernous sinus meningiomas (CSMs) include microsurgical tumor resection, radiotherapy, and radiosurgery. Gamma Knife surgery (GKS) is increasingly being used because it is associated with lower mortality and morbidity rates than microsurgery. The purpose of this study was to assess the role of GKS in the treatment of CSM and to thoroughly analyze the clinical response to GKS.

Methods
Between January 2001 and December 2005, 123 patients (25 men and 98 women; mean age 62.6 ± 11 years, range 31–86 years) who underwent treatment for CSMs were included in this study. Of these, 41 patients underwent microsurgery before GKS, whereas the remaining 82 had GKS as a first-line therapy after a diagnosis was made based on magnetic resonance imaging findings. Dysfunction in cranial nerves (CNs) II, III, IV, V, and VI was noted in 74 patients at the time of GKS. The mean tumor volume was 7.99 cm3 (0.7–30.5 cm3). The mean prescription dose to the tumor margin was 13.8 ± 1.1 Gy (range 10–20 Gy).

Results
The overall tumor control rate was 98.4% with a median follow-up of 36 months. The actuarial tumor control rate at 5 years was 90.5%. A reduction in tumor volume was observed in 53 patients (43.1%), whereas in 68 patients (55.3%) no volumetric variation was recorded. Of the 74 patients who presented with CN deficits, improvement was noted in 23 (31.1%).

Conclusions
Gamma Knife surgery is a useful treatment for CSM both as a first- or second-line therapy. It is a safe and effective treatment for tumors located close to the optic pathways.
CyberKnife rhizotomy for facetogenic back pain: a pilot study
Authors: Li Gordon , Patil Chirag , Adler John R. , Lad Shivanand P. , Soltys Scott G. , Gibbs Iris C. , Tupper Laurie , Boakye Maxwell 
Published: December 2007

Object
By targeting the medial branches of the dorsal rami, radiofrequency ablation and facet joint injections can provide temporary amelioration of facet joint–producing (or facetogenic) back pain. The authors used CyberKnife radiosurgery to denervate affected facet joints with the goal of obtaining a less invasive yet more thorough and durable antinociceptive rhizotomy.

Methods
Patients with refractory low-back pain, in whom symptoms are temporarily resolved by facet joint injections, were eligible. The patients were required to exhibit positron emission tomography–positive findings at the affected levels. Radiosurgical rhizotomy, targeting the facet joint, was performed in a single session with a marginal prescription dose of 40 Gy and a maximal dose of 60 Gy.

Results
Seven facet joints in 5 patients with presumptive facetogenic back pain underwent CyberKnife lesioning. The median follow-up was 9.8 months (range 3–16 months). The mean planning target volume was 1.7 cm3 (range 0.9–2.7 cm3). A dose of 40 Gy was prescribed to a mean isodose line of 79% (range 75–80%). Within 1 month of radiosurgery, improvement in pain was observed in 3 of the 5 patients with durable responses at 16, 12, and 6 months, respectively, of follow-up. Two patients, after 12 and 3 months of follow-up, have neither improved nor worsened. No patient has experienced acute or late-onset toxicity.

Conclusions
These preliminary results suggest that CyberKnife radiosurgery could be a safe, effective, and non-invasive alternative to radiofrequency ablation for managing facetogenic back pain. No patient suffered recurrent symptoms after radiosurgery. It is not yet known whether pain relief due to such lesions will be more durable than that produced by alternative procedures. A larger series of patients with long-term follow-up is ongoing.
Proton radiosurgery in neurosurgery
Authors: Chen Clark C. , Chapman Paul , Petit Joshua , Loeffler Jay 
Published: December 2007

Object
Photon energy deposition from gamma or photon sources follows the law of exponential decay. Consequently, energy is deposited over the entire path of the radiation beam, resulting in dose distribution before and after the target is reached. In contrast, the physical properties of protons are such that energy deposition occurs with no exit dose beyond the target volume. Therefore, relative to photons, proton beams represent a superior platform for the administration of radiosurgery.

Methods
In this review, the authors will discuss the fundamental principles underlying photon- and proton-based stereotactic radiosurgery (SRS). The clinical efficacy of proton-based SRS in the treatment of arteriovenous malformations, vestibular schwannomas, and pituitary adenomas is reviewed.

Results
Direct comparisons of clinical results attained using photon- and proton-based SRS are confounded by a bias toward reserving proton beams for the treatment of larger and more complex lesions. Despite this bias, the clinical outcomes for proton-based SRS have been excellent and have been at least comparable to those for photon-based treatments.

Conclusions
The physical properties of proton radiation offer superior conformality in dose distribution relative to photon irradiation. This advantage becomes more apparent as the lesion size increases and will probably be magnified with the development of intensity-modulated proton techniques.
Gamma Knife stereotactic radiosurgical treatment of idiopathic trigeminal neuralgia: long-term outcome and complications
Authors: Fountas Kostas N. , Smith Joseph R. , Lee Gregory P. , Jenkins Patrick D. , Cantrell Rebecca R. , Sheils W. Chris 
Published: December 2007

Object
Stereotactic radiosurgery (SRS) with the Gamma Knife (GK) is a rapidly emerging surgical modality in the management of medically refractory idiopathic trigeminal neuralgia (TN). The current study examines the long-term outcome in patients with drug-resistant idiopathic TN who underwent GK surgery at the authors‘ institution.

Methods
One hundred and six consecutive patients (38 men and 68 women) with proven medically refractory idiopathic TN were included in this retrospective study. Their ages were 41–82 years (mean 72.3 years). All patients underwent SRS with prescribed maximal radiation doses ranging from 70 to 85 Gy. Isocenters 1–3 were used and plugging was used selectively. The follow-up period was 12–72 months (mean 34.3 months). The patients were divided into 2 groups according to their history of previous surgery.

Results
The initial response rate in patients with no history of previous surgery was 92.9%; in those who had undergone previous surgery, the initial response rate was 85.7%. At the end of the 1st posttreatment year, an excellent outcome was achieved in 82.5% of patients who had not had previous surgery, and in 69.4% of those who had. The respective outcome rates for the 2nd posttreatment year were 78 and 63.5%, respectively. The most common complication was the development of persistent paresthesia, which occurred in 15.8% of patients with no previous surgery and 16.3% of those with previous surgery.

Conclusions
Stereotactic radiosurgery with the GK is a safe and effective treatment option for patients with medically refractory idiopathic TN.
Optic radiation tractography integrated into simulated treatment planning for Gamma Knife surgery
Authors: Maruyama Keisuke , Kamada Kyousuke , Shin Masahiro , Itoh Daisuke , Masutani Yoshitaka , Ino Kenji , Tago Masao , Saito Nobuhito 
Published: December 2007

Object
No definitive method of preventing visual field deficits after stereotactic radiosurgery for lesions near the optic radiation (OR) has been available so far. The authors report the results of integrating OR tractography based on diffusion tensor (DT) magnetic resonance imaging into simulated treatment planning for Gamma Knife surgery (GKS).

Methods
Data from imaging studies performed in 10 patients who underwent GKS for treatment of arteriovenous malformations (AVMs) located adjacent to the OR were used for the simulated treatment planning. Diffusion tensor images performed without the patient's head being secured by a stereotactic frame were used for DT tractography, and the OR was visualized by means of software developed by the authors. Data from stereotactic 3D imaging studies performed after frame fixation were coregistered with the data from DT tractography. The combined images were transferred to a GKS treatment-planning workstation. Delivered doses and distances between the treated lesions and the OR were analyzed and correlated with posttreatment neurological changes.

Results
In patients presenting with migraine with visual aura or occipital lobe epilepsy, the OR was located within 11 mm from AVMs. In a patient who developed new quadrantanopia after GKS, the OR had received 32 Gy. A maximum dose to the OR of less than 12 Gy did not cause new visual field deficits. A maximum dose to the OR of 8 Gy or more was significantly related to neurological change (p < 0.05), including visual field deficits and development or improvement of migraine.

Conclusions
Integration of OR tractography into GKS represents a promising tool for preventing GKS-induced visual disturbances and headaches. Single-session irradiation at a dose of 8 Gy or more was associated with neurological change.
Radiosurgery for chordomas and chondrosarcomas of the skull base
Authors: Martin Juan J. , Niranjan Ajay , Kondziolka Douglas , Flickinger John C. , Lozanne Karl A. , Lunsford L. Dade 
Published: December 2007

Object
Chordomas and chondrosarcomas of the skull base are aggressive and locally destructive tumors with a high tendency for local progression despite treatment. The authors evaluated the effect of stereotactic radiosurgery (SRS) on local tumor control and survival.

Methods
Twenty-eight patients with histologically confirmed chordomas (18) or chondrosarcomas (10) underwent Gamma Knife SRS either as primary or adjuvant treatment. Their ages ranged from 17 to 72 years (median 44 years). The most common presenting symptom was diplopia (26 patients, 93%). In two patients, SRS was the sole treatment. Twenty-six patients underwent between one and five additional surgical procedures. Two underwent an initial trans-sphenoidal biopsy. The average tumor volume was 9.8 cm3. The median dose to the tumor margin was 16 Gy.

Results
No patient was lost to follow-up. Transient symptomatic adverse radiation effects developed in only one patient. The actuarial local tumor control for chondrosarcomas at 5 years was 80 ± 10.1%. For chordomas both the actuarial tumor control and survival was 62.9 ± 10.4%.

Conclusions
Stereotactic radiosurgery is an important option for skull base chordomas and chondrosarcomas either as primary or adjunctive treatment. Multimodal management appears crucial to improve tumor control in most patients.
Peripheral nerve lesions associated with missile-induced pseudoaneurysms
Authors: Roganović Zoran , Mišović Sidor , Kronja Goran , Savić Milenko 
Published: December 2007

Object
Reports of traumatic pseudoaneurysms associated with nerve compression are rare, and typically do not focus on the damaged nerves. This prospective study examines the clinical presentation, management, and treatment outcome of such nerve injuries.

Methods
Between 1991 and 1995, 22 patients with a missile-induced nerve injury associated with a pseudoaneurysm were treated surgically at the Belgrade Military Medical Academy. The artery and nerves involved with the injury were treated using appropriate surgical procedures, and both the sensorimotor deficit and pain intensity were assessed.

Results
The occurrence of a pulsatile mass depended on the location of the pseudoaneurysm (p = 0.003) and correlated significantly with the preoperative diagnosis (p < 0.001). In cases in which neurological worsening was due exclusively to the compressive effect of the pseudoaneurysm, the nerves involved were found to be in anatomical continuity intraoperatively, and recovery depended on the actual nerve damage and surgical procedure required (neurolysis or nerve grafting). A symptomatic nerve compression duration of more than 3.5 days was the critical factor that determined if neurapraxia developed into severe nerve damage (p = 0.014). Pain syndromes responded well and rapidly to the surgical treatment (p < 0.001).

Conclusions
Whether or not a missile-induced pseudoaneurysm associated with a nerve lesion will be recognized before surgery depends on its location and clinical presentation. The nerves involved almost invariably exhibit a lesion in continuity, but the resulting nerve damage can be severe, particularly if surgery is delayed for more than 3 to 4 days after neurological worsening has begun. A successful outcome may be expected if an appropriate surgical technique (neurolysis or grafting) is chosen on the basis of the intraoperative discovery of nerve action potentials.
Deep brain stimulation for treatment of obesity in rats
Authors: Sani Sepehr , Jobe Kirk , Smith Adam , Kordower Jeffrey H. , Bakay Roy A. E. 
Published: December 2007

Object
Given the success of deep brain stimulation (DBS) in a variety of applications (for example, Parkinson disease and essential tremor), other indications for which there is currently little effective therapy are being evaluated for clinical use of DBS. Obesity may be one such indication. Studies of the control of feeding and appetite by neurosurgical lesioning have been completed previously. This study was conducted to test the authors' hypothesis that continuous bilateral stimulatory inhibition of the rat lateral hypothalamic nucleus (LH) would lead to significant and sustained decrease in food intake and subsequent weight loss.

Methods
Sixteen Sprague–Dawley rats were maintained on a high-fat diet. Daily food intake and weight gain were measured for 7 days, at which time the animals underwent stereotactic placement of 0.25-mm-diameter bipolar stimulating electrodes bilaterally in the LH. On postoperative Day 7, eight animals began to receive continuous stimulation of the LH. The remaining eight animals were left unstimulated as the control group. Individual animal weight, food intake, and water intake were monitored daily and continuously throughout the experiment until postoperative Day 24.

Results
There was a decreased rate of weight gain after surgery in all animals, but the unstimulated group recovered and resumed a linear weight gain curve. The stimulated group, however, failed to show weight gain and remained below the mean baseline for body mass. There was a significant weight loss between the stimulated and unstimulated groups. On postoperative Day 24, compared with the day of surgery (Day 0), the unstimulated group had a mean weight gain of 13.8%, whereas the stimulated group had a 2.3% weight loss on average (p = 0.001), yielding a 16.1% weight difference between the two groups.

Conclusions
Bilateral electrical stimulatory inhibition of the LH is effective in causing significant and sustained weight loss in rats.
Connectivity of the human pedunculopontine nucleus region and diffusion tensor imaging in surgical targeting
Authors: Muthusamy Kalai A. , Aravamuthan Bhooma R. , Kringelbach Morten L. , Jenkinson Ned , Voets Natalie L. , Johansen-Berg Heidi , Stein John F. , Aziz Tipu Z. 
Published: December 2007

Object
The pedunculopontine nucleus (PPN) region of the brainstem has become a new stimulation target for the treatment of gait freezing, akinesia, and postural instability in advanced Parkinson disease (PD). Because PD locomotor symptoms are probably caused by excessive γ-aminobutyric acidergic inhibition of the PPN, low-frequency stimulation of the PPN may overcome this inhibition and improve the symptoms. However, the anatomical connections of this region in humans are not known in any detail.

Methods
Diffusion weighted magnetic resonance (MR) images were acquired at 1.5 teslas, and probabilistic tractography was used to trace the connections of the PPN region in eight healthy volunteers. A single seed voxel (2 × 2 × 2 mm) was chosen in the PPN just lateral to the decussation of the superior cerebellar peduncle, and the Diffusion Toolbox of the Oxford Centre for Functional Magnetic Resonance Imaging of the Brain was used to process the acquired MR images. The connections of each volunteer's PPN region were analyzed using a human brain MR imaging atlas.

Results
The PPN region was connected with the cerebellum and spinal cord below and to the thalamus, pallidum, subthalamic nucleus, and motor cortex above. The regions of the primary motor cortex that control the trunk and upper and lower extremities had the highest connectivity compared with other parts of motor cortex.

Conclusions
These findings suggest that connections of the PPN region with the primary motor cortex, basal ganglia, thalamus, cerebellum, and spinal cord may play important roles in the regulation of movement by the PPN region. Diffusion tensor imaging tractography of the PPN region may be used preoperatively to optimize placement of stimulation electrodes and postoperatively it may also be useful to reassess electrode positions.
Effect of treatment plan quality on outcomes after radiosurgery for vestibular schwannoma
Authors: Beegle Richard D. , Friedman William A. , Bova Frank J. 
Published: December 2007

Object
The goal in this study was to review the effects of treatment plan quality on outcomes after radiosurgery for vestibular schwannoma (VS).

Methods
Between July 1988 and August 2005, 390 patients were treated. The results of this experience have been published recently. In this study the authors looked at dosimetry variables: conformity of treatment plan and steepness of dose gradient, in the same group of patients. Over the duration of this study, dosimetry evolved from a single isocenter with marginal conformity to multiple isocenters with high conformity. Multivariate statistics were used to determine the effects of these variables on tumor control and on two types of complication, facial weakness and facial numbness.

Results
The 5-year actuarial tumor control was 91%. Dosimetry had no effect on tumor control. Eighteen patients (4.6%) reported new-onset facial weakness and 14 (3.6%) reported new-onset facial numbness. Since 1994, when peripheral treatment doses were lowered to 1250 cGy, only three (1%) of 298 patients have experienced facial weakness and two (0.7%) of 298 have experienced facial numbness. Statistical analysis confirms, as in the prior study, that treatment volume and treatment dose are significant predictors of both facial weakness and facial numbness. In this model, prior tumor growth was also significant. Dosimetry, however, is definitely not a significant predictor of either complication.

Conclusions
Treatment dose appears to be much more important than treatment plan quality in the prevention of facial numbness or weakness after radiosurgery for VS.