Placebo responses to medical device therapy for pain

Placebo response to a functionless machine was tested in 58 patients with chronic pain. Thirteen discontinued treatment before the planned trials were complete: 5 did so because sham therapy worsened their pain. Forty-five patients completed three trials of treatment with a magnetic device, one trial of which was a sham. Thirteen percent of patients undergoing sham therapy experienced relief of pain, improved range of motion, and decrease in muscle spasm. Eleven percent of the sham trials resulted in significant increase in pain. The placebo/nocebo response to sham therapy with a device is similar to that previously reported for prolonged drug treatment, but is lower than the placebo rate for short-term medication trials.

Microphysiological recordings at CT gantry site during stereotactic thalamotomy

Neural unit recording was performed during CT-guided stereotactic thalamotomy in 2 patients referred for severe cerebellar ataxia and dysmetric movements. Periodic CT scanning was performed during the recording in order to verify probe location and trajectory. Our experience with electrophysiological recordings at the CT gantry site demonstrates the feasibility of acquiring satisfactory neural unit recordings in spite of the high-voltage environment.

Electrophysiological recordings during spinal surgery

Experience with electrophysiological monitoring during surgery of the spinal vertebrae and spinal cord is reviewed. The cerebral somatosensory evoked potential (CSEP) is used to monitor spinal cord conductivity during mechanical manipulation of the vertebrae, most commonly during correction of the curvature of the spine. Abnormal CSEPs were recorded in 11 out of approximately 700 cases of scoliosis surgery. During percutaneous cordotomy, intracord evoked and spontaneous potentials are recorded in order to identify the cord structure. Experiment models are also discussed.

Quantification of thermal asymmetry. Part 1: Normal values and reproducibility

The use of thermography in evaluating nerve injury is based on the presence of temperature asymmetries between the involved area of innervation and the corresponding area on the opposite side of the body. However, interpretation of the thermographic image has been troubled by subjectivity. This paper describes a computer-calculated method of collecting data that eliminates subjective biases. Comprehensive normative data are presented on the degree of thermal asymmetry in the human body. The degree of thermal asymmetry between opposite sides of the body (delta T) is very small. For example, the value of delta T for the forehead (mean +/- standard deviation) was 0.18 degree +/- 0.18 degree C, for the leg it was 0.27 degree +/- 0.2 degree C, and for the foot it was 0.38 degree +/- 0.31 degree C. These values were reproducible in both short- and long-term follow-up measurements over a period of 5 years. The delta T's reported here were obtained from 40 matched regions of the body surface of 90 asymptomatic normal individuals. These values can be used as a standard in assessment of sympathetic nerve function, and the degree of asymmetry is a quantifiable indicator of dysfunction.

Quantification of thermal asymmetry. Part 2: Application in low-back pain and sciatica

Temperature differences between the lower extremities were measured using a computerized thermometric scanning system in order to compare the degree of thermal asymmetry in 144 patients with low-back pain. The patients displayed highly significant thermal asymmetries, with the involved limb being cooler (p less than 0.001). When asymmetries exceeded 1 standard deviation from the mean temperature of homologous regions measured in 90 normal control subjects, the positive predictive value of thermometry in detecting root impingement was 94.7% and the specificity was 87.5%. These values indicate that calculation of temperature asymmetry is particularly effective in evaluating reported pain in psychosocially affected patient populations in whom the chance of positive myelography or impaired root function is low. In this group of patients, thermometric study provides physicians with important information for proper decision making. The test can be performed to avoid more invasive and probably less revealing diagnostic or exploratory surgical procedures.

Spinal cord monitoring during posterior spinal instrumentation and fusion

Two hundred seventy-five consecutive patients who were treated by posterior spinal instrumentation and fusion with iliac crest bone graft were intraoperatively monitored using cortical somatosensory-evoked potentials without a planned wake-up test. The monitoring was performed using a TECA TE-4 system that included an electromyograph, a nerve stimulator, and a digital averager. Intraoperatively, six patients (2%) demonstrated significant changes in evoked potentials, consisting of either marked increase in latency or a loss of wave form during instrumentation of the spine. The instrumentation was removed immediately and the evoked potentials returned to base-line tracing within 15-30 minutes in all six cases. Five patients who had instruments refitted to maintain a lesser amount of correction had no subsequent change in the evoked potentials. One patient had spinal fusion without instrumentation. Postoperatively, all patients are neurologically normal.

The complementary role of indium-111 labeled leukocyte imaging, ultrasonography and computed tomography in the evaluation of postoperative infection or abscess

We report our experiences with the combined use of indium-111 labeled leukocyte imaging (In-III WBC scan.), computed tomography (CT) and ultrasonography (US) for evaluation of suspected postoperative infection or abscess, and discuss the complementary roles of these modalities. Postoperative abscesses or infections were diagnosed in 9 of 20 patients. All patients were correctly diagnosed by In-111 WBC imaging and 4 patients could not be diagnosed by US because of bowel gas. One false-positive CT examination and another artifact on CT images due to respiratory movements were obtained. The three modalities were found to be complementary: CT and US were efficient imaging methods for diagnosis and treatment of abscess. In-111 WBC imaging could estimate the activity of inflammation.

[Necessary radiological items for radiation therapy of esophageal cancer]

Necessary items for radiation therapy of an esophageal cancer are discussed in detail. These radiological items can be dissolved through the radiological findings by use of the fine double contrast method of treating the esophagus. One method is to dissolve the infiltrative depth of the esophageal cancer; the other is the radiological diagnostic method to dissolve the effect of the radiation therapy on the esophageal cancer. In fact, regarding the former, the classification of the X-ray type is essential and depends upon the infiltrative depth of the cancer and, for the latter, the radiological findings before and after irradiation must be compared.

[The criteria of radiotherapy for treating carcinoma of the esophagus]

The criteria of radiation therapy is given for the treatment of a carcinoma of the esophagus, said criteria decided by a committee of the Japanese Association for Radiotherapy Systems at the request of the Japan Radiological Society. The indication for radiation therapy is described and adapted to the new TNM Classification, based on the depth of the invasion of the tumor. The depth of the tumor invasion is divided into 4 stages and the radiological images for each are shown. To evaluate the effect of radiotherapy, cases are divided into curable and non-curable groups, according to the degree of changes of the radiological findings after irradiation, and each group is further subdivided into absolute and relative categories.

Rett syndrome: new observations

Two elderly females with Rett syndrome are reported with evidence of a slowly progressive central and distal peripheral nervous system involvement. Thermography in 4 girls confirmed distal hypothermia of the extremities in a glove and stocking distribution. Unilateral sympathectomy during surgery for scoliosis in one of them resulted in increased warmth and physical growth of the foot and nails, compared to the uninjured side. This suggests increased sympathetic tone as the probable cause of distal hypothermia, vasomotor instability and dystrophy of the feet in this disorder. In an attempt to identify a marker, girls with clinically classical Rett syndrome had plasma and urinary cell evaluation for an unusual glycolipid. A blind study using a small number of patients failed to prove absolute specificity and additional studies are required to evaluate its validity as a marker for Rett syndrome.

Helmet for infant skull fixation during stereotactic neurosurgery

A thermoplastic helmet was designed to allow the use of the Leksell stereotactic frame in infants.

Magnetic resonance planned thalamotomy followed by X-ray/CT-guided thalamotomy

Magnetic resonance imaging (MRI) is currently the optimal neuroradiologic technique for visualizing the anterior and posterior commissure for defining the AC-PC line. CT is the optimal technique for electrode and probe guidance during stereotactic thalamotomy. Various possibilities of transferring or overlying MRI and CT are outlined which in some future might result in more refined methods of CT-MRI guidance for stereotactic surgery.

Intraoperative CT monitoring during stereotactic brain surgery

This paper reports our experience in performing the entire stereotactic surgical procedure with a CT scanner, which shows that target shifting can occur as the probe approaches the target. Therefore, when sampling of small targets or specific sites within larger targets is desired. CT confirmation of the probe's position ensures that the specific area seen on CT is biopsied.

[Performance of gamma camera collimators used for single photon emission computed tomography imaging with 123I-isopropyl iodoamphetamine]

123I Produced by 124Te(p, 2n)123I reaction is contaminated with 124I (less than 5%) and 126I (less than 0.3%). High energy photons from these mixed radioiodine compromise seriously image quality due to scattered photons and to septal penetration in the collimator. Four collimators of LEAP (for low energy all purpose), LEHR (for low energy high resolution), MESI (for medium energy made by Siemens) and MENU (for medium energy made by nuclear technology) mounted on a rotating gamma camera (Siemens, ZLC-7500), were examined in order to select a suitable collimator for 123I SPECT (single photon emission computed tomography) imaging. Sensitivities were measured with a plane source (5 X 5 X 0.5 cm) at the collimator face and distances from 2 to 30 cm in air. And, spatial resolutions in FWHM (full width at half maximum) and FWTM (full width at tenth maximum) were determined from line spread functions with planar and SPECT imaging. From the comparison of collimator performances with 99mTc and 123I, both collimators for low energy were not useful for 123I imaging. In other two collimators for medium energy, however, apparently the effect of septal penetration by the higher energy photons were also recognized, MENU with high geometrical resolution was more suitable for 123I SPECT imaging compared with MESI. And, it is important to perform the SPECT imaging with radius as short as possible.