Evaluation of gamma thalamotomy for parkinsonian and other tremors: survival of neurons adjacent to the thalamic lesion after gamma thalamotomy

2000 ◽  
Vol 93 (supplement_3) ◽  
pp. 120-127 ◽  
Author(s):  
Chihiro Ohye ◽  
Tohru Shibazaki ◽  
Junji Ishihara ◽  
Jie Zhang
Keyword(s):  
Tissue Reaction ◽  
Vascular Lesions ◽  
Thalamic Lesion ◽  
Mr Images ◽  
Unsatisfactory Result ◽  
Content Type ◽  
Rhythmic Discharge ◽  
Latent Interval ◽  
Fine Print

Object. The effects of gamma thalamotomy for parkinsonian and other kinds of tremor were evaluated. Methods. Thirty-six thalamotomies were performed in 31 patients by using a 4-mm collimator. The maximum dose was 150 Gy in the initial six cases, which was reduced to 130 Gy thereafter. The longest follow-up period was 6 years. The target was determined on T2-weighted and proton magnetic resonance (MR) images. The point chosen was in the lateral-most part of the thalamic ventralis intermedius nucleus. This is in keeping with open thalamotomy as practiced at the authors' institution. In 15 cases, gamma thalamotomy was the first surgical procedure. In other cases, previous therapeutic or vascular lesions were visible to facilitate targeting. Two types of tissue reaction were onserved on MR imaging: a simple oval shape and a complex irregular shape. Neither of these changes affected the clinical course. In the majority of cases, the tremor subsided after a latent interval of approximately 1 year after irradiation. The earliest response was demonstrated at 3 months. In five cases the tremor remained. In four of these cases, a second radiation session was administered. One of these four patients as well as another patient with an unsatisfactory result underwent open thalamotomy with microrecording. In both cases, depth recording adjacent to the necrotic area revealed normal neuronal activity, including the rhythmic discharge of tremor. Minor coagulation was performed and resulted in immediate and complete arrest of the remaining tremor. Conclusions. Gamma thalamotomy for Parkinson's disease seems to be an alternative useful method in selected cases.

Accelerated spondylotic changes adjacent to the fused segment following central cervical corpectomy: magnetic resonance imaging study evidence

2004 ◽  
Vol 100 (1) ◽  
pp. 2-6 ◽  
Author(s):  
Vaijayantee Kulkarni ◽  
Vedantam Rajshekhar ◽  
Lakshminarayan Raghuram
Keyword(s):  
Magnetic Resonance ◽  
Mr Imaging ◽  
Imaging Study ◽  
Degenerative Changes ◽  
Adjacent Segment ◽  
Mr Images ◽  
Short Term ◽  
Content Type ◽  
Fine Print

Object. The authors studied whether cervical spine motion segments adjacent to a fused segment exhibit accelerated degenerative changes on short-term follow-up magnetic resonance (MR) imaging. Methods. Preoperative and short-term follow-up (mean duration 17.5 months, range 10–48 months) cervical MR images obtained in 44 patients who had undergone one- or two-level corpectomy for cervical spondylotic myelopathy were evaluated qualitatively and quantitatively. The motion segment adjacent to the fused segment and a segment remote from the fused segment were evaluated for indentation of the thecal sac, disc height, and sagittal functional diameter of the spinal canal on midsagittal T2-weighted MR images. Thecal sac indentations were classifed as mild, moderate, and severe. New indentations of the thecal sac of varying severity (mild in 17 patients [38.6%], moderate in 10 [22.7%], and severe in six [13.6%]) had developed at the adjacent segments in 33 (75%) of 44 patients. The degenerative changes were seen at the superior level in 11 patients, inferior level in 10 patients, and at both levels in 12 patients and resulted from both anterior and posterior element degeneration in the majority (23 [69.6%]) of patients. The remote segments showed mild thecal sac indentations in seven patients and moderate indentations in two patients (nine [20.5%] of 44). Compared with the changes at the remote segment, the canal size was significantly decreased at the superior adjacent segment by 0.9 mm (p = 0.007). No patient sustained a new neurological deficit due to adjacent-segment changes. Conclusions. On short-term follow-up MR imaging, levels adjacent to the fused segment exhibited more pronounced degenerative changes (compared with remote levels) in 75% of patients who had undergone one- or two-level central corpectomy.

Remote congenital cerebral arteriovenous fistulae associated with aortic coarctation

1992 ◽  
Vol 76 (1) ◽  
pp. 137-142 ◽  
Author(s):  
Francis H. Tomlinson ◽  
David G. Piepgras ◽  
Douglas A. Nichols ◽  
Daniel A. Rüfenacht ◽  
Sue C. Kaste
Keyword(s):  
Caesarean Section ◽  
Aortic Coarctation ◽  
Coarctation Of The Aorta ◽  
Vascular Lesions ◽  
Prenatal Ultrasonography ◽  
Arteriovenous Fistulae ◽  
Content Type ◽  
The Right ◽  
Fine Print

✓ A neonate presented with anatomically discrete cerebral arteriovenous fistulae located in the right sylvian fissure and the cerebellar vermis that were initially detected by prenatal ultrasonography. Following delivery of the baby by Caesarean section, both malformations were treated by surgical obliteration. These intracranial vascular lesions were associated with cardiac anomalies and a periductal coarctation of the aorta, which was treated with a left subclavian rotational arterial pedicle repair. Follow-up examination of the infant at age 13 months demonstrated an excellent clinical result with normalization of the circulation. The pathophysiology of this syndrome is discussed and the literature reviewed.

Salvage retreatment after failure of radiosurgery in patients with arteriovenous malformations

2003 ◽  
Vol 98 (2) ◽  
pp. 337-341 ◽  
Author(s):  
Kelly D. Foote ◽  
William A. Friedman ◽  
Thomas L. Ellis ◽  
Frank J. Bova ◽  
John M. Buatti ◽  
...  
Keyword(s):  
Treatment Failure ◽  
Initial Treatment ◽  
Primary Treatment ◽  
Size Reduction ◽  
Cure Rate ◽  
Mr Images ◽  
Content Type ◽  
The Mean ◽  
Fine Print

Object. The goal of this study was to evaluate the outcomes of patients who underwent repeated radiosurgery to treat a residual intracranial arteriovenous malformation (AVM) after an initial radiosurgical treatment failure. Methods. The authors reviewed the cases of 52 patients who underwent repeated radiosurgery for residual AVM at the University of Florida between December 1991 and June 1998. In each case, residual arteriovenous shunting persisted longer than 36 months after the initial treatment; the mean interval between the first and second treatment was 41 months. Each AVM nidus was measured at the time of the original treatment and again at the time of retreatment, and the dosimetric parameters of the two treatments were compared. After retreatment, patients were followed up and their outcomes were evaluated according to a standard posttreatment protocol for radiosurgery for AVMs. The mean original lesion volume was 13.8 cm3 and the mean volume at retreatment was 4.7 cm3, for an average volume reduction of 66% after the initial treatment failure. Only two AVMs (3.8%) failed to demonstrate size reduction after the primary treatment. The median doses on initial and repeated treatment were 12.5 and 15 Gy, respectively. Five patients were lost to follow up and five refused neuroimaging follow up. One patient died of a hemorrhage shortly after retreatment. Of the remaining 41 patients, 24 had evidence of cure, 15 on angiographic studies and nine on magnetic resonance (MR) images. Seventeen had evidence of treatment failure, 10 on angiographic studies and seven on MR images. By angiographic criteria alone, the cure rate after retreatment was 60%, whereas according to angiographic and MR imaging results, the cure rate was 59%. Conclusions. Although initial radiosurgical treatment failed to obliterate the AVM in these 52 patients, it did produce a substantial therapeutic effect (volume reduction). This size reduction commonly allowed higher doses to be delivered during radiosurgical retreatment. The results show rates of angiographically confirmed cure comparable to primary treatment and a low incidence of complications, indicating that salvage radiosurgical retreatment is a safe and effective therapy in cases of failed AVM radiosurgery.

Association between a black band on the inner membrane of a chronic subdural hematoma on T2*-weighted magnetic resonance images and enlargement of the hematoma

2003 ◽  
Vol 99 (5) ◽  
pp. 824-830 ◽  
Author(s):  
Toshio Imaizumi ◽  
Yoshifumi Horita ◽  
Toshimi Honma ◽  
Jun Niwa
Keyword(s):  
Surgical Treatment ◽  
Magnetic Resonance ◽  
Chronic Subdural Hematoma ◽  
Magnetic Resonance Images ◽  
Mr Images ◽  
Inner Membrane ◽  
Content Type ◽  
Black Band ◽  
Fine Print

Object. The cause and indication for enlargement of chronic subdural hematomas (CSDHs) have remained unresolved. The authors observed a black band on the inner membrane of a CSDH on T2*-weighted magnetic resonance (MR) images obtained in patients with symptoms. After surgical treatment, the band disappeared. The T2*-weighted sequence of MR imaging is an excellent diagnostic tool for detecting ferromagnetic substances, but it is rarely performed in cases of a CSDH. The authors speculate that the black band may be associated with the development of CSDH. Methods. To investigate how the black band observed on T2*-weighted MR images contributes to the development of a CSDH, 59 lesions in 50 patients with CSDH (41 men and nine women, mean age 70 ± 11 years [range 48–93 years]) were investigated prospectively. The incidence of black bands on the first T2*-weighted MR image obtained in patients with symptomatic CSDH was 97% (31 of 32 CSDHs), which was significantly higher than that associated with asymptomatic CSDH (11% [three of 27 CSDHs], p < 0.001). The black bands associated with symptomatic CSDH disappeared soon after surgical treatment in 31 CSDHs and became fainter in another. In two instances the CSDH recurred with reappearance of the band. Twenty-four of 27 asymptomatic CSDHs had no accompanying black band. Follow-up MR images demonstrated a later formation of bands in two of 24 asymptomatic CSDHs that enlarged to symptomatic size. Logistic regression analysis revealed that the heterogeneity and thickness of the CSDH on computerized tomography scans were independently and significantly associated with the black band. Conclusions. The dynamics of the black band may depend on the enlargement or shrinkage of the CSDH.

Use of a bioabsorbable anterior cervical plate in the treatment of cervical degenerative and traumatic disc disruption

2002 ◽  
Vol 97 (4) ◽  
pp. 473-480 ◽  
Author(s):  
Alexander R. Vaccaro ◽  
John A. Carrino ◽  
Benjamin H. Venger ◽  
Todd Albert ◽  
Peter M. Kelleher ◽  
...  
Keyword(s):  
Soft Tissue ◽  
Tissue Reaction ◽  
Content Type ◽  
Single Level ◽  
Soft Tissue Reaction ◽  
Solid Fusion ◽  
Cervical Plate ◽  
Anterior Cervical Plate ◽  
Fine Print

Object. Anterior cervical discectomy and fusion (ACDF) is a widely accepted treatment for anterior degenerative or traumatic instability of the cervical spine. To reduce or eliminate complications such as implant migration and failure, imaging degradation, and fusion stress shielding that are occasionally associated with spinal instrumentation, attention has been given to the use of bioresorbable anterior cervical plate (ACP) devices. This paper is a preliminary report of a retrospective series in which a resorbable mesh and screw system was used for graft containment in single-level ACDF. Methods. A review of patient charts and imaging studies was conducted to determine functional outcome, fusion success, and potential soft-tissue reaction to implant resorption. Nine patients with a cervical degenerative disc disease or traumatic disc disruption were treated between October 2001 and March 2002. Follow up averaged 206 days. Eight patients were found to have an excellent result, one patient had a good result, and no patients had a satisfactory or poor result. At the time of follow-up examination, 77% of patients were found to have a radiographically solid fusion. The two patients without a solid fusion were examined only an average 8 months postoperatively and manifested no symptoms related to fusion nonhealing. No significant soft-tissue reaction was noted clinically or radiographically in any of the patients. Conclusions. The results of this preliminary study indicate that bioresorbable ACP systems for single-level ACDF are both safe and effective.

Surgical outcomes in 118 patients with Rathke cleft cysts

2005 ◽  
Vol 102 (2) ◽  
pp. 189-193 ◽  
Author(s):  
Christopher J. Aho ◽  
Charles Liu ◽  
Vladimir Zelman ◽  
William T. Couldwell ◽  
Martin H. Weiss
Keyword(s):  
Visual Impairment ◽  
Recurrence Rate ◽  
Cyst Wall ◽  
Hormone Deficiency ◽  
High Recurrence Rate ◽  
Endocrine Dysfunction ◽  
Mr Images ◽  
Content Type ◽  
Fine Print

Object. Microscopic Rathke cleft cysts are a common incidental autopsy finding, but some Rathke cleft cysts can become sufficiently large to cause visual impairment, hypothalamic—pituitary dysfunction, and headaches. In this study patients were evaluated pre- and postoperatively to ascertain the clinical significance of surgical intervention on endocrine and visual improvement. Factors correlated with cyst recurrence were also evaluated. Methods. A retrospective analysis was conducted in 160 patients with Rathke cleft cysts who were treated between 1984 and 1995 and completed at least a 5-year follow-up period. Of these 160 patients, 118 initially exhibited symptoms of visual impairment or endocrine dysfunction, became symptomatic during the follow-up period, or were found to have cyst enlargement. These 118 patients underwent transsphenoidal surgery. Forty-two patients with incidental lesions that demonstrated no growth on magnetic resonance (MR) images were followed up without an operation. Complete resection, as observed on MR images 3 months postoperatively, was obtained in 114 (97%) of 118 patients. Vision improved postoperatively in 57 (98%) of 58 patients. Hypogonadism improved in 11 (18%) of 62 patients, growth hormone deficiency resolved in 14 (18%) of 78 patients, and hypocortisolemia resolved in one (14%) of seven patients. Twenty-two patients (19%) began to exhibit symptoms of diabetes insipidus, which had not been present preoperatively. The total 5-year recurrence rate was 18% (21 of 118 patients), with 12 patients requiring a repeated operation. Surgical and pathological factors that were found to be statistically associated with recurrence were the use of a fat and/or fascial graft for closure (p < 0.01) and the presence of squamous metaplasia in the cyst wall (p < 0.01). The extent of resection of the cyst wall was not associated with an increased rate of recurrence. In 42 (69%) of 61 patients the incidental cysts did not progress on imaging studies or clinically. Conclusions. This is the largest series of patients with symptomatic Rathke cleft cysts who received operative intervention and participated in the longest postoperative follow up reported in the literature. The high recurrence rate (18%) supports the theory that a relationship exists between a symptomatic Rathke cleft cyst and craniopharyngioma. Improvements in visual and endocrine dysfunction can be expected after surgical decompression of the optic apparatus and the hypothalamic—pituitary axis.

The natural history of familial cavernous malformations: results of an ongoing study

1994 ◽  
Vol 80 (3) ◽  
pp. 422-432 ◽  
Author(s):  
Joseph M. Zabramski ◽  
Thomas M. Wascher ◽  
Robert F. Spetzler ◽  
Blake Johnson ◽  
John Golfinos ◽  
...  
Keyword(s):  
Natural History ◽  
Mr Imaging ◽  
Ongoing Study ◽  
Mr Images ◽  
Cavernous Malformations ◽  
Content Type ◽  
Imaging Characteristics ◽  
Familial Form ◽  
Fine Print

✓ Cavernous malformations are congenital abnormalities of the cerebral vessels that affect 0.5% to 0.7% of the population. They occur in two forms: a sporadic form characterized by isolated lesions, and a familial form characterized by multiple lesions with an autosomal dominant mode of inheritance. The management of patients with cavernous malformations, particularly those with the familial form of the disease, remains a challenge because little is known regarding the natural history. The authors report the results of an ongoing study in which six families afflicted by familial cavernous malformations have been prospectively followed with serial interviews, physical examinations, and magnetic resonance (MR) imaging at 6- to 12-month intervals. A total of 59 members of these six families were screened for protocol enrollment; 31 (53%) had MR evidence of familial cavernous malformations. Nineteen (61%) of these 31 patients were symptomatic, with seizures in 12 (39%), recurrent headaches in 16 (52%), focal sensory/motor deficits in three (10%), and visual field deficits in two (6%). Twenty-one of these 31 patients underwent at least two serial clinical and MR imaging examinations. A total of 128 individual cavernous malformations (mean 6.5 ± 3.8 lesions/patient) were identified and followed radiographically. During a mean follow-up period of 2.2 years (range 1 to 5.5 years), serial MR images demonstrated 17 new lesions in six (29%) of the 21 patients; 13 lesions (10%) showed changes in signal characteristics, and five lesions (3.9%) changed significantly in size. The incidence of symptomatic hemorrhage was 1.1% per lesion per year. The results of this study demonstrate that the familial form of cavernous malformations is a dynamic disease; serial MR images revealed changes in the number, size, and imaging characteristics of lesions consistent with acute or resolving hemorrhage. It is believed that the de novo development of new lesions in this disease has not been previously reported. These findings suggest that patients with familial cavernous malformations require careful follow-up monitoring, and that significant changes in neurological symptoms warrant repeat MR imaging. Surgery should be considered only for lesions that produce repetitive or progressive symptoms. Prophylactic resection of asymptomatic lesions does not appear to be indicated.

Temporal Lobe Epilepsy

2005 ◽  
Vol 103 (4) ◽  
pp. 768-769 ◽  
Author(s):  
Ross P. Carne ◽  
Terence J. O'Brien ◽  
Christine J. Kilpatrick ◽  
Lachlan R. MacGregor ◽  
Rodney J. Hicks ◽  
...  
Keyword(s):  
Temporal Lobe Epilepsy ◽  
Clinical Features ◽  
Temporal Lobe ◽  
Granule Cells ◽  
Hippocampal Slices ◽  
Mr Images ◽  
Content Type ◽  
Dentate Granule Cells ◽  
Fine Print

Abstract Object. The syndrome of medial temporal lobe epilepsy (MTLE) may occur in patients in whom magnetic resonance (MR) images demonstrate normal findings. In these patients, there is no evidence of hippocampal sclerosis on neuroimaging, and histopathological examination of the resected hippocampus does not reveal significant neuron loss. In this paper the authors describe the distinct clinical features of this MTLE subtype, referred to as paradoxical temporal lobe epilepsy (PTLE). Methods. The authors selected 12 consecutive patients with preoperative findings consistent with MTLE in whom MR imaging did not demonstrate any hippocampal abnormality. Onset of hippocampal seizure was confirmed by long-term intracranial monitoring. There were six female and six male patients with a mean age of 32 ± 11 years (mean ± standard deviation [SD]) at presentation. These patients' seizure histories, available hippocampal volumetric measurements, and hippocampal cell densities in different subfields were reviewed. Sharp electrode recordings from dentate granule cells that had been maintained in hippocampal slices provided a measure of excitation and inhibition in the tissue. We compared these data with those of a cohort of 50 randomly selected patients who underwent anteromedial temporal resection for medial temporal sclerosis (MTS) during the same time period (1987–1999). The durations of follow up (means ± SDs) for the PTLE and MTS groups were 51 ± 59 months and 88 ± 44 months, respectively. A history of febrile seizure was present less frequently in the PTLE group (8%) than in the MTS group (34%). Other risk factors for epilepsy such as trauma, meningoencephalitis, or perinatal injuries were present more frequently in the PTLE group (50%) than in the MTS cohort (36%). In patients in the PTLE group the first seizure occurred later in life (mean age at seizure onset 14 years in the PTLE group compared with 9 years in the MTS group, p = 0.09). Ten patients (83%) in the PTLE cohort and 23 patients (46%) in the MTLE cohort had secondary generalization of their seizures. Among patients with PTLE, volumetric measurements (five patients) and randomized blinded visual inspection (seven patients) of the bilateral hippocampi revealed no atrophy and no increased T2 signal change on preoperative MR images. All patients with PTLE underwent anteromedial temporal resection (amygdalohippocampectomy, in five patients on the left side and in seven on the right side). Electrophysiological studies of hippocampal slices demonstrated that dentate granule cells from patients with PTLE were significantly less excitable than those from patients with MTS. The mean pyramidal cell loss in the CA1 subfield in patients in the PTLE group was 20% (range 0–59%) and that in patients in the MTS group was 75% (range 41–90%) (p < 0.001). Maximal neuron loss (mean loss 38%) occurred in the CA4 region in six patients with PTLE (end folium sclerosis). At the last follow-up examination, six patients (50%) in the PTLE group were seizure free compared with 38 patients (76%) in the MTS group. Conclusions. Clinical PTLE is a distinct syndrome with clinical features and surgical outcomes different from those of MTS.

Magnetic resonance imaging: an accurate method to evaluate arteriovenous malformations after stereotactic radiosurgery

1996 ◽  
Vol 85 (6) ◽  
pp. 1044-1049 ◽  
Author(s):  
Bruce E. Pollock ◽  
Douglas Kondziolka ◽  
John C. Flickinger ◽  
Atul K. Patel ◽  
David J. Bissonette ◽  
...  
Keyword(s):  
Magnetic Resonance Imaging ◽  
Magnetic Resonance ◽  
Mr Imaging ◽  
Cerebral Angiography ◽  
False Negative ◽  
Resonance Imaging ◽  
Mr Images ◽  
Content Type ◽  
Fine Print

✓ To determine the accuracy of magnetic resonance (MR) imaging in comparison to cerebral angiography after radiosurgery for an arteriovenous malformation (AVM), the authors reviewed the records of patients who underwent radiosurgery at the University of Pittsburgh Medical Center before 1992. All patients in the analysis had AVMs in which the flow-void signal was visible on preradiosurgical MR imaging. One hundred sixty-four postradiosurgical angiograms were obtained in 140 patients at a median of 2 months after postradiosurgical MR imaging (median 24 months after radiosurgery). Magnetic resonance imaging correctly predicted patency in 64 of 80 patients in whom patent AVMs were seen on follow-up angiography (sensitivity 80%) and angiographic obliteration in 84 of 84 patients (specificity 100%). Overall, 84 of 100 AVMs in which evidence of obliteration was seen on MR images displayed angiographic obliteration (negative predictive value, 84%). Ten of the 16 patients with false-negative MR images underwent follow-up angiography: in seven the lesions progressed to complete angiographic obliteration without further treatment. Exclusion of these seven patients from the false-negative MR imaging group increases the predictive value of a negative postradiosurgical MR image from 84% to 91%. No AVM hemorrhage was observed in clinical follow up of 135 patients after evidence of obliteration on MR imaging (median follow-up interval 35 months; range 2–96 months; total follow up 382 patient-years). Magnetic resonance imaging proved to be an accurate, noninvasive method for evaluating the patency of AVMs that were identifiable on MR imaging after stereotactic radiosurgery. This imaging modality is less expensive, more acceptable to patients, and does not have the potential for neurological complications that may be associated with cerebral angiography. The risk associated with follow-up cerebral angiography may no longer justify its role in the assessment of radiosurgical results in the treatment of AVMs.

Transarterial embolization of aneurysms associated with spinal cord arteriovenous malformations

1999 ◽  
Vol 90 (1) ◽  
pp. 148-154 ◽  
Author(s):  
Alexis Victorien Konan ◽  
Jean Raymond ◽  
Daniel Roy
Keyword(s):  
Spinal Cord ◽  
Arteriovenous Malformations ◽  
Transarterial Embolization ◽  
Apparent Volume ◽  
Anterior Spinal Artery ◽  
Mr Images ◽  
Content Type ◽  
Hemorrhagic Events ◽  
Fine Print

✓ The authors sought to show the feasibility and discuss the rationale of embolization of aneurysms associated with spinal cord arteriovenous malformations (SCAVMs). The authors reviewed the clinical presentation, magnetic resonance (MR) images, spinal angiograms, and clinical evolution of four patients treated for aneurysms associated with an SCAVM. Aneurysms were located on branches of the anterior spinal artery in three patients and on radiculopial arteries in two patients; one patient harbored two lesions. Treatment consisted of superselective bucrylate embolization of the branches harboring the aneurysms, with preservation of the arterial axis. Follow-up angiograms were obtained at 3 to 6 months postembolization in all patients. All patients presented with hemorrhagic events. Hematomyelia was clearly related to a sulcocommissural or a vasa corona aneurysm in two patients. Another sulcocommissural aneurysm and multiple radiculopial aneurysms were presumed to be the cause of subarachnoid hemorrhage in two other patients. One patient harbored aneurysms on a sulcocommissural artery and on a radiculopial artery. All aneurysms were permanently obliterated. In one patient with a single fistula, the SCAVM was cured. The SCAVM was only partially obliterated (95, 50, and 20% in apparent volume) in three other patients. There were no complications or rebleeding episodes during a follow-up period of 17 to 37 months. Aneurysms associated with SCAVMs can be eradicated by supraselective embolization, even on the anterior spinal artery territory. For patients presenting with hemorrhage and prohibitive risk of complete resection, embolization of aneurysms may decrease the risk of further rebleeding.

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