Stereotactic navigation for placement of pedicle screws in the thoracic spine

OBJECTIVE: Pedicle screw fixation in the lumbar spine has become the standard of care for various causes of spinal instability. However, because of the smaller size and more complex morphology of the thoracic pedicle, screw placement in the thoracic spine can be extremely challenging. In several published series, cortical violations have been reported in up to 50% of screws placed with standard fluoroscopic techniques. The goal of this study is to evaluate the accuracy of thoracic pedicle screw placement by use of image-guided techniques. METHODS: During the past 4 years, 266 image-guided thoracic pedicle screws were placed in 65 patients at the University of Michigan Medical Center. Postoperative thin-cut computed tomographic scans were obtained in 52 of these patients who were available to enroll in the study. An impartial neuroradiologist evaluated 224 screws by use of a standardized grading scheme. All levels of the thoracic spine were included in the study. RESULTS: Chart review revealed no incidence of neurological, cardiovascular, or pulmonary injury. Of the 224 screws reviewed, there were 19 cortical violations (8.5%). Eleven (4.9%) were Grade II (< or =2 mm), and eight (3.6%) were Grade III (>2 mm) violations. Only five screws (2.2%), however, were thought to exhibit unintentional, structurally significant violations. Statistical analysis revealed a significantly higher rate of cortical perforation in the midthoracic spine (T4-T8, 16.7%; T1-T4, 8.8%; and T9-T12, 5.6%). CONCLUSION: The low rate of cortical perforations (8.5%) and structurally significant violations (2.2%) in this retrospective series compares favorably with previously published results that used anatomic landmarks and intraoperative fluoroscopy. This study provides further evidence that stereotactic placement of pedicle screws can be performed safely and effectively at all levels of the thoracic spine.     

Urgent surgery in colon carcinoma

INTRODUCTION: About 10% of all operations in colon carcinoma are performed in emergency situations because of severe preoperative complications. PATIENTS AND METHOD: The prospectively collected data of 1496 patients with colon carcinoma treated from 1987 to 2002 at the Department of Surgery of the University of Erlangen were analysed with special interest on postoperative morbidity and long-term prognosis after elective and urgent surgery. RESULTS: The rate of urgent surgery was 11%. The most frequent complication was bowel obstruction (73%) followed by perforation (20%). Emergency patients were significantly older (p<0.001) and in worse general condition (p<0.001). The rates of surgical and nonsurgical postoperative complications were higher in urgent surgery than in elective surgery (28.8% vs. 19.8%, p=0.015) and also postoperative mortality was significantly higher (10.1% vs. 4.0%, p<0.001). The rates of locoregioanal recurrences and distant metastases were significantly higher. Urgent surgery was found to be an independent prognostic factor for distant metastasis (relative risk 1.8) and cancer-related survival (relative risk 1.6). DISCUSSION: Urgent surgery in colon carcinoma is usually performed in advanced tumours of elderly patients. This operation can be a challenge for the treating surgeon. Adequate medical emergency supply needs to provide an experienced surgeon for those interventions.     

Efficacy and safety of perioperative infusion of levosimendan in patients with compromised cardiac function undergoing open-heart surgery: importance of early use.

OBJECTIVE: Levosimendan is a promising new inotrope. We investigate the proper time for its infusion during or after open-heart surgery to avoid complications related with low-output syndrome and high dosage of inotropes. METHODS: Forty-five consecutive patients were randomised to receive levosimendan in addition to the conventional therapy, its infusion starting in the operating theatre (Group OT) or in the ICU (Group ICU) when low-output syndrome was certified and were consequently dependent on classical inotropic support and IABP. Levosimendan was infused at a rate of 0.1 microg/kg min without loading dose, the infusion being for at least 24h to a maximum 48 h. RESULTS: Levosimendan was well tolerated, with the simultaneous infusion of norepinephrine if required. Its efficacy was identical in both groups with improvement in the haemodynamic and functional status of patients (amelioration of stroke volume, cardiac index and mixed venous blood oxygen saturation, increase of left ventricular ejection fraction by echo study, de-escalation of traditional inotropes, subtraction of IABP and reduction in BNP plasma levels). The ICU stay and hospital stay were significantly decreased in patients of Group OT, compared to patients of Group ICU. Four patients died because of multiple organs dysfunction syndrome (MODS) due to sepsis (all patients of Group ICU). CONCLUSION: Levosimendan is a safe and efficient choice in the management of low-output syndrome during and after open-heart surgery. The shortening of hospitalisation and the trend for better outcome confirm its clear superiority when the infusion starts from the operating theatre.     

Autologous platelet-rich plasma (PRP) effect on intervertebral disc restoration: an experimental rabbit model

European Journal of Orthopaedic Surgery & Traumatology - Platelet-rich plasma (PRP) treatment for intervertebral disc (IVD) repair and tissue engineering technologies have been the target of...     

An autonomous in situ detection system for radioactivity measurements in the marine environment.

A new detection system named "KATERINA" is developed and applied for measuring marine radioactivity using NaI(Tl) as a crystal. This apparatus is designed for qualitative and quantitative radionuclide detection in the marine environment with maximum depth of deployment 400m. A detailed study for the enclosure of the system and for the electronics development is performed. The system offers volumetric activities in Bq/m(3) using the marine efficiency calibration, which is measured by dilution of three reference sources ((99m)Tc, (137)Cs, and (40)K) in a special tank. The calibration procedures for energy, energy resolution and efficiency were analyzed with particular attention to the factors that affect the calibration parameters. The underwater detector is tested in the field for acquiring radon daughters ((214)Pb and (214)Bi) in a region where submarine groundwater discharge exists in the coastal zone.     

Evaluation of the role of varicocelectomy including external spermatic vein ligation in patients with scrotal pain

OBJECTIVES: The aim of the present study was to assess and compare pre- and postoperative scrotal pain in patients with varicocele who underwent varicocelectomy with different approaches. METHODS: The study included 144 consecutive patients with left-sided varicocele who had left scrotal pain for more than 3 months. All patients underwent varicocele ligation using either a subinguinal or inguinal approach with or without external spermatic vein ligation. We asked the patients to complete an 'Assessment Questionnaire for Scrotal Pain' both before and after the surgery. RESULTS: The surgery was successful in 101 (83.4%) of the 121 patients available for follow up. Seventy-four (61.1%) patients reported the complete resolution of pain while 27 patients (22.3%) reported partial resolution. Symptoms worsened in a single case and pain persisted postoperatively in 19 cases (15.7%). There were no statistically significant differences in the characteristics of the pain and grade of varicocele between postoperative groups. A significant difference was observed in postoperative success between patients who had external spermatic vein ligation and those who did not, regardless of the surgical approach (inguinal or subinguinal). All patients who reported complete or partial resolution of pain stated that they would recommend surgery to relatives with the same problem. CONCLUSIONS: Varicocelectomy using either inguinal or subinguinal approaches is an effective and reasonable treatment option in this patient group and should include external spermatic vein ligation for a satisfactory outcome.     

Accuracy of single-time, multilevel registration in image-guided spinal surgery.

BACKGROUND CONTEXT: Computerized frameless stereotactic image-guidance has been used in recent years to improve the accuracy and safety of pedicle screw placement during spine surgery. Because the possibility of intervertebral motion exists, and because the patient is usually in a different position when preoperative imaging is performed compared with the operative position, it has been suggested that the imaging model of the complete lumbar spine and the surgically exposed lumbar spine may be significantly discordant. Consequently, current protocols suggest registering each spinal level (single-level registration) separately before pedicle screw placement at that level, a time-consuming process. PURPOSE: To assess the accuracy of single-time multilevel registration for multilevel pedicle screw placement during image-guided, computer-assisted spine surgery, in the setting of degenerative disorders of the lumbar spine. STUDY DESIGN/SETTING: This is a prospective clinical and radiological study of 45 patients with degenerative disorders of the lumbar spine who underwent instrumented fusion with the use of single-time multilevel registration computer-assisted, image-guided tomography. The accuracy of the pedicle screws placement was confirmed on the basis of a protocol that included intraoperative spontaneous electromyographic (EMG) recordings, direct pedicle visualization, and computer tomography (CT) scans when clinically indicated during the follow-up period. PATIENT SAMPLE: Forty-five consecutive patients who fulfilled the criteria of computer-assisted, image-guided tomography pedicle screw placement for degenerative lumbar spine disease without overt instability. OUTCOME MEASURES: The principal outcome measure was the accuracy of pedicle screw placement with single-time multilevel registration for multilevel pedicle screw placement during image-guided, computer-assisted spine surgery; postoperative CT performed for clinical indications during the follow-up course was used for the assessment of pedicle screw placement. METHODS: Patients were assessed clinically before and after the operation. Data from 45 consecutive cases of image-guided, computer-assisted lumbar spinal fusion were statistically analyzed to determine the relationship between the number of levels registered during single-time registry and the mean registration error (MRE). Intraoperative spontaneous EMG, direct visualization, and postoperative CT scans were used to assess the accuracy of pedicle screw insertion. RESULTS: None of the patients involved in this study experienced clinical sequelae of improper pedicle screw placement. MREs after surface mapping and after point merge were small (less than 1.00 mm and less than 3.00 mm, respectively). During the intraoperative assessment of the pedicle screws placement, no significant spontaneous EMG activity was recorded and the pedicular walls were found intact in direct visualization. The postoperative CT scans showed in 10 patients accurate placement in 55 of the 57 pedicle screws with expansion of the medial wall in two screws. CONCLUSIONS: Single-time, multilevel registration may decrease operative time relative to repeated, single-level registrations, without compromising the increased accuracy of pedicle screw placement afforded by this technique in the setting of degenerative disorders of the lumbar spine. Despite the advantages in computer-guided image surgery, cautious application in the individual patient is recommended until more comprehensive data can be gathered in specific degenerative pathology with overt instability; thus the knowledge of the anatomy remains crucial.     

Laparoscopic management of a ruptured giant epidermoid splenic cyst.

BACKGROUND: Epidermoid splenic cysts are uncommon lesions of the spleen. They are known to become symptomatic as a consequence of enlargement, infection, or rupture, the latter being an exceedingly rare complication traditionally treated with open splenectomy. We herein report a unique case of a giant epidermoid splenic cyst that ruptured spontaneously and was successfully treated with the laparoscopic approach. CONCLUSION: Laparoscopic surgery may be considered an initial treatment option in cases of very large epidermoid cysts even when rupture occurs.     

电脉冲介导基因转移效率的实验研究

目的　研究电脉冲介导的基因转移效率及其最佳的基因转移的电脉冲参数。方法　用微量注射器将pcD2/LacZ质粒10μg,在昆明小鼠的股四头肌注射,1～2min内在注射部位给予不同参数的电脉冲刺激(不同的电脉冲参数每组10只小鼠),然后进行β-半乳糖苷酶活性的测定或酶组织化学染色。同时设空白对照组及单纯注射组。结果　电脉冲可明显增加LacZ基因的表达,电脉冲组的β-半乳糖苷酶活性（131.6U/mg±86.5U/mg蛋白）是单纯注射组（4.9U/mg±1.0U/mg蛋白）的30倍（P<0.05）。组织化学染色结果表明电脉冲组肌肉组织中β-半乳糖苷酶蓝色颗粒的数目和染色的程度均明显高于单纯肌肉注射组。当电脉冲参数电压200V/cm,波宽40ms,脉冲次数6次和频率1Hz时,可获得最高的基因表达效率。结论　在最佳的电脉冲参数条件下,电脉冲介导的基因转移可获得较高的基因表达。     

不稳定性心绞痛患者血清hs-CRP、TnI、CK-MB的研究

目的探讨不稳定性心绞痛患者血清hs—CRP、TnI、CK—MB变化及测定的临床意义。方法利用乳胶增强免疫比浊法和电化学发光法，对154例健康人群、112例uA患者、68例SA患者检测其血清hs—CRP、TnI和CK—MB的水平。结果UA组hs-CRP、TnI、CK—MB水平明显高于SA组（P〈0．01），更远远高于健康组（P〈O．01），并且sA组此三项检测也明显高于健康组（P〈0．05），UA组和SA组及健康组存在显著差异。结论如果将hs—CRP、TnI、CK—MB联合检测，对冠心病的早期诊断，尤其是对不稳定性心绞痛的早期发现及危险性预测，具有重大的现实意义。