Superimposed holographic image-guided neurosurgery. Technical note

Computerized tomography scanning-derived narrow band reflection holograms of patients undergoing craniofacial procedures were created to evaluate the applicability of superimposing these three-dimensional images (3-D) on the operative field during neurological surgery. These sterilized radiological holograms were positioned over the surgical site by using bone sutures as registration points between the skull and the 3-D image to serve as a visual template between the patient and surgeon. Surgeries were then performed with the surgeon looking through the radiological hologram at the patient. Holograms were accurate to within 2 mm (plus or minus) of the actual calvarial anatomy. The use of the holographic image as a visual guide during surgery eliminated intraoperative guesswork or free-handed contouring. To the author's knowledge, this is the first report of the superimposed holographic image used in situ during surgery.     

Endoscopic microscopic transpedicular thoracic discectomy. Technical note

In an effort to make thoracic discectomy simple and less invasive while using direct visualization, a 70 degrees-angled lens endoscope has been adopted to visualize the ventral aspect of the spinal cord dura mater during microsurgical thoracic discectomy via a transpedicular approach. The patient is positioned in a 60 degrees forwardly inclined lateral position with the side of the lesion facing upward. After radiographic corroboration of the correct level, a transpedicular approach is made using a 1.5-cm-diameter tubular retractor through a 2-cm-long paramedian transverse skin incision. With the aid of an operating microscope, the ipsilateral facet joint, including the upper portion of the pedicle, is removed using a high-speed drill, thus exposing the neural foramen, intervertebral disc, and upper portion of the pedicle leading to the vertebral bodies. When the herniated disc and bone spur have been removed laterally in relation to the spinal cord, creating a cavity under the operating microscope, a 4-mm-diameter rigid endoscope with a 70 degrees-angled lens is mounted to an endoscope holder so that the ventral aspect of the spinal cord dura mater can be visualized directly. With the aid of direct endoscopic visualization, the disc and bone spur, which compress the spinal cord anteriorly, are pushed away toward a cavity created at the intervertebral space and are removed using a downward-biting long-armed curette. Patients with myelopathy are kept overnight in the hospital; however, those with radiculopathy are discharged home on the same day as their operation. The surgical technique and two illustrative cases are reported.     

A stereotactic guide for microsurgery. Technical note

A stereotactic guide for microsurgery is presented. The guide consists of a weak helium neon laser projecting a red beam towards the target when the arc carrying the beam has been set on the Leksell frame according to the stereotactic co-ordinates of the target calculated on the pre-operative imaging studies. The device allows free manoeuverability of the operating microscope.     

Acquisition of new concepts by two amnesic patients

Two Korsakoff amnesics (A.G. and G.S.) and two control subjects were taught six new concepts. Each concept was composed of three parts: the name of the concept, the context in which the concept originated and its definition. The learning procedure consisted of two phases: (1) learning the concept names and definitions by means of the vanishing-cues method; (2) practice on examples of the concepts through a classification task: examples were either set in the same context as that given in the original definition or in mixed contexts (same and new contexts). Subjects were then tested after 24 hours, a week and a month on their ability to identify new examples as belonging to one of the conceptual rules studied (transfer tests). Both patients showed substantial learning. Patient A.G. was slow and dependent of the first letter cues in the vanishing-cues learning phase but nevertheless, she acquired a large and flexible conceptual knowledge and this was especially true for concepts that were practised by means of mixed-context examples. Patient G.S. easily learned to associate the definitions with the concept names but her conceptual knowledge remained more limited. These results confirm the existence of a semantic learning ability in amnesic patients. They also suggest that under appropriate learning conditions, amnesics may eventually acquire a new flexible conceptual knowledge.     

Circular stereotactic callosotomy: a preliminary report. Technical note

The authors propose a new method for performing stereotactic callosotomy, which they have named circular callosotomy. The operating device is the original Riechert-Mundinger's string electrode, which can be protruded through a side window and by rotating the probe it is possible to cut the commisural pathways to the extent required. The anatomical results of the operation can be checked using MRI scanning.     

Local anesthesia in anal surgery. Technical note and immediate results

The authors report their experience with the use of local anesthesia in anal surgery (hemorrhoids, anal fissures and fistulas). They describe their technique in detail, stressing the importance of thorough knowledge of the neuroanatomy of the anal canal and of a stepwise blockage of all sensory and motor fibers to the area. They report their results on 300 anal procedures performed under local anesthesia, with good patient acceptance.     

Magnetic resonance imaging-compatible posterior cervical implant for occipitocervical stabilization. Technical note

Posterior cervical stabilization was accomplished in 30 patients (19 females and 11 males) by using sublaminar titanium cables and a new titanium bullet-shaped implant. Seventeen patients underwent occipitocervical fixation and 13 others were treated subaxially. These patients have been followed for 18 to 52 months (mean 36 months), and no implant has failed during the follow-up period.     

Abbreviated kinetic profiles in area-under-the-curve monitoring of cyclosporine therapy. Technical note

BACKGROUND: The new microemulsion formulation of cyclosporine (CsA-ME) displays more consistent pharmacokinetic properties than the original formulation and may allow successful implementation of an abbreviated area-under-the-curve (AUC) strategy. METHODS: Here we compared two limited sampling strategies in order to define the one that best predicts AUC after CsA-ME in 51 renal transplant recipients with stable renal function. Pharmacokinetics were based on analysis of blood samples collected over 12 hours after drug administration by high-performance liquid chromatography (HPLC). Predicted AUC was estimated by using a three-point (0, 1 and 3 hr) or a two-point (2 and 6 hr or 0 and 2 hr) sampling strategy. RESULTS: A simplified strategy with three time points of blood collection at 0, 1, and 3 hours after CsA-ME allowed adequate and accurate prediction of the daily exposure to CsA. AUC prediction with two-point sampling at 2 and 6 hours was less good with a very large error in prediction (only 59% of the estimated AUC were within the accepted range). This limitation was even more evident when the 0 and 2 hour time points were examined, in which only 51% of AUC estimates were included in the accepted range of variation (-10 to 10%). CONCLUSIONS: A limited strategy of three-point sampling taken early after dosing allows an excellent and perfectly reliable prediction of the actual AUC.     

有关压力减敏两个概念的讨论

讨论了压力减敏与药包间距之间的关系,建立了减敏程度与药包间距关系的理想化模型.针对实际情况提出并深入讨论了药包的临界压死距离和临界减敏距离两个概念.用这两个概念来描述压力减敏与药包间距之间的关系更加合理,可以加深对炸药的压力减敏现象的认识,有助于毫秒爆破炮孔参数设计.     

Waterjet dissection of the brain: experimental and first clinical results. Technical note

Axons from central neurons can regenerate into the tissue matrix formed within a silicone tube capped with two pieces of peripheral nerve, one of which had been sutured to a lesion in the spinal cord. Such axons can grow through a transversely positioned microchip in the tube. These observations suggest that it is feasible to establish functional contact between external electronic equipment and regenerating central nervous axons making it possible to monitor and control their electrical activity. The findings open new perspectives for restoration of motor and sensory functions following spinal cord lesions.     

Breadth of deviate concepts used by schizophrenics.

This study investigated interfering overresponsiveness to a conceptual task in schizophrenics and attempted to isolate other situational conditions under which it occurs. The hypothesis was "the schizophrenic tendency to overinclude in a sorting task is positively related to the degree to which incorrect items share common qualities with the correct items in a given conceptual category." One normal and 2 schizophrenic groups, consisting of 24 males each, served as Ss. The results of the sorting tasks confirmed the hypothesis. An attempt was also made to determine whether schizophrenics showed excessive narrowing of the conceptual basis for sorting, but no difference between schizophrenics and normals was found. (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

Technical note: changes in genetic predictions between subsequent evaluations

A procedure was developed to compute the proportion (P) of future genetic predictions that would be within 1 SE of previous predictions. The procedure is based on the Central Limit Theorem. Whatever the distribution function, provided only that it has a finite variance, the sample mean will have approximately the normal distribution for large samples. The proportion of new individual genetic predictions being within 1 SE of their previous evaluation is expressed as a function of the change in accuracy (ACC) between the previous and subsequent evaluations. If little additional information is made available since the previous evaluation, the increase in ACC will be almost negligible. As anticipated the vast majority of genetic predictions will be within 1 SE of their previous evaluation. The proportion determined from the results of the analysis can be compared to P. An additional appealing feature of the procedure presented is the ease of implementation with most computer softwares. Finally, application to both simulated and field data is presented.     

Countertransference and empathy: The complex relationship between two divergent concepts in counseling.

Examined the relationship of 20 male counselor trainees' empathic ability (the Barret-Lennard Relationship Inventory) to measures of countertransference behavior and countertransference feelings toward 20 undergraduate female clients. It was expected that empathic ability would be negatively related to the manifestation of countertransference behavior, operationalized as the withdrawal of personal involvement, but positively related to self-reports of openness to countertransference feelings. Empathy was found to be negatively related to countertransference behavior with seductive female clients but not with hostile or neutral clients. Counselor empathic ability was positively related to counselor reports of openness to countertransference feelings. Findings suggest, however, that there was a limit to how often countertransference feelings could be experienced in a given counseling session without spilling over into countertransference behavior. (17 ref) (PsycINFO Database Record (c) 2010 APA, all rights reserved)     

A burr hole button to secure the electrode cable in depth electrode placement. Technical note

A simple magnetic resonance imaging-compatible buttonlike device was devised to fix a depth electrode cable securely in the burr hole used for its insertion during surgery for depth electrode placement. The button is tightly fixed in the burr hole and it holds the cable without allowing protrusion or tension on the wound.     

RNA metabolism in uremic patients: accumulation of modified ribonucleosides in uremic serum. Technical note

To determine the metabolism of ribonucleic acid (RNA) in uremia, serum and urine levels of ribonucleosides in uremic patients were analyzed using reversed-phase high-performance liquid chromatography. The serum levels of xanthosine and all modified ribonucleosides were increased in undialyzed patients with chronic renal failure (CRF), and patients undergoing hemodialysis (HD) and continuous ambulatory peritoneal dialysis (CAPD). The serum level of pseudouridine was markedly increased in all the uremic patients especially CAPD patients (32 times higher than normal). By contrast, the serum level of adenosine did not show any significant change in the uremic patients. Interestingly, the serum and urine levels of inosine were significantly decreased in all the uremic patients, suggesting that the production of inosine is decreased in uremic patients. The serum level of uridine was significantly elevated only in the HD patients. The serum levels of all ribonucleosides except inosine and uridine decreased significantly after HD. The urinary excretion of inosine, 1-methyladenosine, 1-methylguanosine, N2,N2-dimethylguanosine and N4-acetylcytidine was significantly decreased in the CRF patients, leading to the accumulation of these modified ribonucleosides in the uremic serum. CAPD patients showed markedly increased serum levels of modified ribonucleosides such as pseudouridine, 1-methylinosine, and N2,N2-dimethylguanosine and N4-acetylcytidine as compared with the HD patients. These results demonstrate that there was an altered metabolism of RNA in uremic patients with marked accumulation of modified ribonucleosides.     

Technical note: equine skeletal preservation techniques to enhance teaching effectiveness

When the decision was made to euthanatize an acutely laminitic Thoroughbred broodmare, graduate students from the Department of Animal Sciences and Industry reconstructed the skeleton for use as a teaching tool. The reproductive and gastrointestinal tracts were removed and preserved in formalin. The hide, muscle, tendons, ligaments, and organs were removed, and the bones were boiled in water for > or = 48 h to remove all remaining tissue. After boiling, the bones were soaked in gasoline to remove fat from the marrow cavities and then soaked in a bleach/detergent mixture as a final cleaning step. The bones were allowed to dry for several weeks, then a semi-gloss clear lacquer was applied to aid in preservation. The bones were connected with 17-gauge wire and supported by two 1.91-cm galvanized steel rods on a mobile platform. The vertebral column was aligned on flexible copper tube with a 1.27-cm diameter. Additional support was provided for the head and neck by aluminum and steel rods extending from the front support. The final product is a complete, mobile skeleton that will be used as a teaching aid in equine classes. The skeleton serves a function for all levels of the cognitive learning domain. Examples of applications include memorization, identification, and location of bones; use in case studies for synthesis and demonstration of brainstorming efforts; and evaluation of joint ailments for more advanced levels of learning.     

Technical note: physical evaluation of recent Kodak films for mammography

Four Kodak films for mammography were evaluated for image quality and dose. Processing times and storage effects have also been evaluated.