Solomon Batnitzky’s research while affiliated with University of Kansas Medical Center and other places

The cost of recording and archiving digital diagnostic imaging data is presented for a Radiology Department serving a 614 bed University-Hospital with a large outpatient population. Digital diagnostic imaging modalities include computed tomography, nuclear medicine, ultrasound, and digital radiography. The archiving media include multiformat video film recordings, magnetic tapes, and disc storage. The estimated cost per patient for the archiving of digital diagnostic imaging data is presented.

The relative accuracy of starting point algorithms in microelectrode-guided stereotactic pallidotomy and thalamotomy was evaluated using postoperative magnetic resonance imaging (MRI) data. Multiplanar reformations were performed to align postoperative MRI in anterior-posterior, dorsal-ventral and mediolateral planes. Three-dimensional distance and direction from the pallidal and thalamic stereotactic starting points to the respective radiofrequency lesions were measured. Similar magnitude of microelectrode refinement in pallidotomy and thalamotomy suggested similar accuracy of algorithms used to set the stereotactic starting point. Fewer microelectrode-recording tracts were required to identify optimal lesioning sites in thalamotomy compared to pallidotomy. Lesions were consistently localized anterior and superior to the starting point and a refined starting point algorithm may reduce the number of microelectrode recording tracts.

Microelectrode recording can refine targeting for stereotactic radiofrequency lesioning of the globus pallidus to treat Parkinson's disease. Multiple intraoperative microelectrode recording/stimulating tracks are searched and assessed for neuronal activity, presence of tremor cells, visual responses, and responses to kinesthetic input. These physiological data are then correlated with atlas-based anatomic data to approximate electrode location. On the basis of these physiological properties, one or more tracks are selected for lesioning. This study analyzes the track physiological factors that seem most significant in determining the microelectrode recording track(s) that will be chosen for pallidal lesioning. Thirty-six patients with Parkinson's disease underwent microelectrode-guided pallidotomy. Between one and five microelectrode recording tracks were made per patient. Usually, one (n = 23) or two (n = 12) of these tracks were lesioned. Electrode positions in the x (mediolateral) and y (anteroposterior) axes were recorded and related to track neurophysiological findings and final lesion location. The stereotactic location and sequence of microelectrode tracks were recorded and plotted to illustrate individual search patterns. These patterns were then compared with those noted in other patients. Neurophysiological data obtained from recording tracks were analyzed. A retrospective analysis of track electrophysiology was performed to determine the track characteristics that seemed most important in the surgeon's choice of the track to lesion. Track physiological properties included general cell spike amplitude, tremor synchronous neuronal firing, kinesthetically responsive neuronal firing, and optic track responses (either phosphenes reported by the patient during track microstimulation or neuronal firing in response to light stimulus into the patient's eyes). Orthogonally corrected postoperative magnetic resonance images were used to confirm the anatomic lesion locations. In patients who had a single mapped track lesioned, specific track electrophysiological characteristics identified the track that would be lesioned most of the time (20 of 24 patients). Tracks that exhibited a combination of tremor synchronous firing, joint kinesthesia, and visual responsivity were lesioned 17 (85%) of 20 times. Analysis of intraoperative electrode movement in the x and y axes indicated a significant subset of moves but did not result in microelectrode positioning closer to the subsequently lesioned track. Accuracy of initial electrode movement in the x and y axes was most highly correlated with a measure of first-track electrophysiological activity. The number of microelectrode recording tracks did not correlate with clinical outcome. Anatomic analysis, using postoperative magnetic resonance imaging, revealed that all lesions were placed in the globus pallidus. Most patients (35 of 36) improved after surgery. The level of electrophysiological activity in the first track was the best predictive factor in determining whether the next microelectrode move would be closer to the ultimately lesioned track. The analysis of electrode track location and neurophysiological properties yields useful information regarding the effectiveness of microelectrode searching in the x and y axes. Within an institution, the application of this modeling method may increase the efficiency of the microelectrode refinement process.

Peripheral intracranial aneurysms can be difficult to treat with traditional surgical or embolization techniques that spare the parent vessel. We report the results of our use of coil occlusion of the parent vessel for the treatment of nine peripheral intracranial aneurysms. During approximately a 4-year period, nine patients (six men and three women, 27 to 68 years old; average age, 42 years) presented to our institution with peripheral intracranial aneurysms. The aneurysms were located on branches of the right posterior inferior cerebellar artery (n = 2), the right superior cerebellar artery (n = 1), the right anterior inferior cerebellar artery (n = 1), the right posterior cerebral artery (n = 3), the left middle cerebral artery (n = 1), and the left anterior cerebral artery (n = 1). Parent vessel occlusion was performed using microcoils after test injection with amobarbital (Amytal) in eight of the nine cases (one patient was comatose and could not be tested before occlusion). Angiography immediately after the procedure showed aneurysmal occlusion in every patient. Follow-up arteriography, performed in six patients 2 to 12 months after treatment, documented continued aneurysmal occlusion in every case. Three patients exhibited mild, nondisabling neurologic deficits after coil placement; the rest had no new deficits, although one patient was severely disabled from the initial hemorrhage and one patient died of an unrelated cause. Our results lend support to the use of parent vessel occlusion for peripheral aneurysms that are difficult to treat surgically or that are not amenable to intra-aneurysmal coil placement.

Objective: Our objective is to describe the use of percutaneous transluminal angioplasty in eight patients with symptomatic high-grade atherosclerotic intracranial internal carotid artery stenoses. We describe our technique for performing the procedure and clinical and radiographic follow-up for an average of 53 months to determine the long-term results. Conclusion: Percutaneous transluminal angioplasty was shown to be an efficacious treatment for symptomatic intracranial internal carotid artery atherosclerotic disease in our group of patients.

To determine whether stereotactic pallidotomy requires refinement using microelectrode recording to ensure proper lesion placement. The experiment approach was based on retrospective comparisons of microelectrode-refined radiofrequency lesion locations with hypothetical unrefined lesion positions. Actual and hypothetical pallidotomy lesions were classified based on their lesion center (thermocoagulative zone) locations and their total lesion areas (surrounding edematous zone) relative to the pallidal target. Assessments were made using postoperative T2-weighted magnetic resonance axial images, which showed both the lesion and globus pallidus (GP). The magnitude of microelectrode refinement from an initial preoperative starting point determined by computed tomography was calculated using stereotactic coordinates and included corrections for the lesioning tract trajectory angle. In all 25 patients, the center of the actual pallidotomy lesion was within the GP. Without microelectrode refinement, 13 of 25 hypothetical lesion positions would have been localized such that the lesion center would not have remained in the GP. In eight cases, microelectrode refinement resulted in no significant change in lesion location, but in one case, microelectrode refinement resulted in lesion center placement away from the GP. Kinesthetically driven microelectrode refinement in pallidotomy lesioning seems to be required to ensure proper lesion location within the GP.

Acute thalamotomy and pallidotomy lesion volumes based on magnetic resonance (MR) images were measured in 22 patients (11 thalamotomy and 11 pallidotomy patients). Thalamotomy inner lesion volumes (0.06 +/- 0.04 ml; thermocoagulative zone) were smaller than pallidotomy inner lesion volumes (0.14 +/- 0.08 ml) as determined using T(1)-weighted 3D-MPRAGE (1.5-mm slice spacing). Similar results were found using T(1)-weighted (6-mm slice spacing) image sets (0.09 +/- 0.05 ml, thalamotomy; 0.13 +/- 0.05 ml, pallidotomy). No differences were found when comparing thalamic or pallidal inner lesion volumes when the comparison was based on T(2) weighted images. Thalamotomy total lesion volumes (thermocoagulative and surrounding edematous zones) were less than pallidotomy total lesion volumes independent of the MR protocol. The difference in thalamotomy and pallidotomy lesion volumes is most likely based on the distance between each discrete lesion placed along the lesioning tracts. In 7 of 11 thalamotomies, this distance was 1 mm with the remaining having 2 mm between each discrete lesion. All pallidotomy discrete lesions were 2 mm apart. More overlap between discrete lesioning sites for thalamotomies is likely to produce reduced lesion volumes.

OBJECTIVE: To assess the position of radiofrequency pallidotomy lesions placed using microelectrode stimulation and cellular recordings in relation to a stereotactically defined starting point. Radiofrequency lesion locations were also evaluated in relation to the putamen, posterior limb of the internal capsule, and optic tract. METHODS: Magnetic resonance images obtained from 23 patients with Parkinson's disease who underwent pallidotomy at the University of Kansas Medical Center were analyzed. Using computerized techniques, lesion positions in relation to the midcommissural point and a hypothetical starting point were determined. Data segmentation and three-dimensional reconstruction of pallidal lesions, the internal capsule, and the optic tract allowed assessment of lesion position in relation to internal anatomy. Clinical outcome of pallidotomy was assessed using both the Unified Parkinson's Disease Rating Scale and the Dementia Rating Scale. RESULTS: Pallidal lesions were usually placed anterior and dorsal to the stereotactically defined starting point. The position of pallidal lesions in the men were observed, in four trials, to be significantly more dorsal than the lesions in the women. The outer zone of the lesion was usually adjacent to the internal capsule and the putamen and relatively close to the optic tract. The inner zone of the lesion was usually several millimeters removed from anatomic boundaries of the putamen, internal capsule, and optic tract. Patients achieved favorable outcomes, with reduced dyskinesias and "off" time and improvement of their Parkinsonian symptoms, as evidenced by clinical assessment, the Unified Parkinson's Disease Rating Scale, and the Dementia Rating Scale. CONCLUSION: Microelectrode stimulation and cellular recordings usually led to a final pallidotomy lesion position that deviated from the stereotactically defined starting point. The pallidotomy lesions in the men were observed to be more dorsal than the lesions in the women. Clinical outcomes were not correlated with either lesion location relative to the starting point or distances between the pallidal lesion and the putamen, internal capsule, or optic tract. Kinesthetically responsive cells may be localized generally more anterior and dorsal to the starting point (within the globus pallidus) and may be grouped variably from patient to patient in relation to other basal ganglia structures. Although the primary lesion site is most likely within the sensorimotor region of the globus pallidus internus, the more dorsal locations of responsive cell groups may indicate that some lesion sites may be localized within the globus pallidus externus.

The authors have addressed the ability of magnetic resonance (MR) imaging to resolve incremental thinning of articular cartilage by assessment of three-dimensional (3-D) and two-dimensional (2-D) representations. Using a porcine knee model, sequential cartilage shavings were characterized using a 3-D fat suppressed spoiled gradient-echo (SPGR) MR imaging protocol that provided good contrast between high-signal articular cartilage and lower signal surrounding tissues. Lesion dimensional measurements were made on both MR images and 3-D computerized reconstructions. Volumes of cartilage removed were approximately 0.06 mL. Incremental articular cartilage thinning typically was apparent on 3-D reconstructed images. Three-dimensional articular cartilage reconstructions were effective in depicting location and orientation of shaved cartilage regions. Average percent error associated with length and with measurements based on 2-D MR images was approximately 19% for observer 1 and 33% for observer 2 when compared with direct measurements of the shaved cartilage. Average percent error of thickness measurements based on 2-D MR was approximately 21% for observer 1 and 37% for observer 2. Overall average errors associated with length, width, and thickness measurements were approximately 25%. Incremental thinning of articular cartilage can be tracked qualitatively and quantitatively using 3-D computerized reconstructions and 2-D MR images. Errors associated with the quantitative measurements can be attributed to limitations of measurement methods and intrinsic limitation of MR resolution.