Spinal deformity in myelodysplasia. Correction with posterior pedicle screw instrumentation

STUDY DESIGN: A retrospective review of transpedicular instrumentation used in a series of 24 patients with myelodysplastic spinal deformities and deficient posterior elements. OBJECTIVE: To describe the usefulness and efficacy of these instruments in the treatment of complicated myelodysplastic spinal deformity. METHODS: The mean preoperative scoliosis was 75.7 degrees (range, 39-130 degrees) in the 22 patients with scoliotic deformities; 4 patients with thoracic hyperkyphoses averaged 70.5 degrees (range, 46-90 degrees) and 10 patients with lumbar kyphoses averaged 80.5 degrees (range, 42-120 degrees). The instrumentation extended to the sacrum in 4 patients and the pelvis in 9; 10 patients also underwent anterior release and fusion and 7 underwent concomitant spinal cord detethering. At an average follow-up of 4.0 years (2.0-7.7 years; one patient died at 8 months), all patients have fused (with the exception of two lumbosacral pseudarthroses). RESULTS: At last follow-up, deformity measured 32.1 degrees scoliosis (range, 6-85 degrees), 30.8 degrees thoracic kyphosis (range, 24-35 degrees), and 0.0 degree lumbar kyphosis (range, 35 degrees kyphosis to 29 degrees lordosis). Three patients lost some neurologic function after surgery; two recovered within 6 months and one has incomplete recovery. No ambulatory patient lost the ability to walk. Five patients required additional surgical procedures; in three cases, there was instrumentation breakage associated with pseudarthrosis or unfused spinal segments. CONCLUSIONS: Pedicle screw instrumentation is uniquely suited to the deficient myelodysplastic spine. Compared with historical control subjects, these devices have proven capable of significant correction of both scoliotic and kyphotic deformities. This instrumentation appears particularly useful in preserving lumbar lordosis in all patients and may preserve more lumbar motion in ambulatory myelodysplasia patients.     

Spinal instrumentation in the management of adolescent scoliosis

A multitude of posterior and anterior segmental spinal instrumentation systems are now available for the treatment of idiopathic scoliosis. As a consequence, fixation strategies are more complex than they were with Harrington instrumentation. The newer systems provide better sagittal control and more stable fixation, allowing quicker mobilization of the patient. On thin patients, the bulk of these implants may be a problem. The techniques of fusion and the fusion levels remain constant.     

Spinal instrumentation without fusion for progressive scoliosis in young children

This report provides comparative physiological data on the features of the regulatory effects of the neurohormone vasopressin on higher nervous activity in an ascending series of mammals consisting of insectivores, rodents, and primates. Administration of vasopressin to hedgehogs produced a general facilitatory effect on conditioned reflex brain activity. The effects of vasopressin on memory processes in hedgehogs was minor. In rabbits, vasopressin had greater regulatory effects on conditioned reflex memory than in hedgehogs. However, this was transient in nature. In monkeys, administration of vasopressin had complex differential effects on simple conditioned responses and different types of memory. The effects of vasopressin on memory processes were long-lasting and were different for corticalized and noncorticalized forms of nervous activity. The question of changes in the nature of the regulatory effects of vasopressin during phylogenesis is discussed, as is the question of the increases in its level of involvement in the regulation of higher nervous functions and memory processes.     

Spinal subdural haematoma: an unusual complication of lumbar puncture

A case in which a spinal subdural haematoma obscured the diagnosis of spinal stenosis is described. The haematoma resulted as a complication of the lumbar puncture necessary for the myelogram. No other aetiological factors were found, but it is suggested that this condition may become more frequent as the result of iatrogenic haemostatic defects.     

The initial complication rate of phacoemulsification in India

PURPOSE: This study was designed to investigate the feasibility of teaching experienced surgeons to perform phacoemulsification in India, a cataract-endemic area. Complications occurring during surgery and the first postoperative day were documented and evaluated. METHODS: During a 1-month period, at the Aravind Eye Hospital in Madurai, India, the first 100 consecutive cataract operations performed by each of three experienced surgeons (a total of 300 cases), using phacoemulsification were prospectively evaluated. Multiple logistic regression was used to identify factors associated with intraoperative and postoperative complications. RESULTS: The mean age of patients was 57.4+/-9.3 years. The median best corrected preoperative visual acuity was 20/80. Mean surgical and phacoemulsification times were 15.8+/-3.7 minutes and 2.2+/-1.5 minutes, respectively. Complications occurred in 65 (21.7%) eyes. The most common was a rent in the posterior capsule, occurring in 40 (13.3%) eyes. There were significant variations in complication rate and in surgical time among the surgeons. The risk of experiencing a complication decreased as the number of phacoemulsifications performed increased. An increased risk of complications was associated with worse preoperative visual acuity and increasing patient age. CONCLUSIONS: With each successive case, the chances of experiencing a complication decreased 1%. Acceptable results were obtained within 1 month of performing the first phacoemulsification.     

Plaque removal with variable instrumentation

The purpose of this study was to evaluate dental plaque removal in a normal healthy mouth, during routine oral hygiene appointments using different techniques and without the use of any disclosing agents. 12 dental hygienists, randomly selected from a continuing education course, were asked to perform oral hygiene on the same patient to remove all the supra-gingival plaque without any time restriction and without the use of a disclosing agents. The plaque index score (O'Leary) was assessed before and after each session with the use of fluorescine and UV light source by an independent examiner. 3 groups of instruments were utilized: group A: ultrasonic scalers + prophy cups; group B: ultrasonic scalers + prophy cups + dental floss; group C: Gracey curettes + prophy cups. While no group was able to remove all the plaque, groups B and C performed significantly better.     

Colovaginal anastomosis: a unique complication of end-to-end anastomosis stapler use in low anterior resection

Anastomotic staplers have been used in colorectal surgery for several years. End-to-end stapler use for low anterior resection, as well as for other procedures, is common in surgical practice. These staplers have allowed more extended, lower resections of the colorectum without loss of bowel continuity or sphincter function. There have been reported complications of stapler use, with anastomotic stricture and leakage being the most common. We report here a unique complication of direct colovaginal anastomosis using the end-to-end stapler during a low anterior resection of an early-stage rectal adenocarcinoma.     

Bacterial reduction with nickel-titanium rotary instrumentation

The purpose of this study was to compare intracanal bacterial reduction on teeth instrumented with 0.04 tapered nickel-titanium (NiTi) rotary instrumentation to bacterial reduction when using a stainless-steel K-file step-back technique using sterile saline irrigation. Forty-eight patients with apical periodontitis were randomly assigned treatment type. The canals were sampled before, during, and after instrumentation. The samples were incubated anaerobically for 7 days at 37 degrees C, colony-forming unit numbers calculated, and a log transformation performed to normalize the counts. Teeth exhibiting apical periodontitis were uniformly infected, whereas vital control teeth were not. A similar and uniform reduction occurred with progressive filing, regardless of technique (p < 0.0001). There was no detectable difference in colony-forming unit count after NiTi rotary or stainless-steel hand instrumentation (p = 0.42). Neither technique could predictably render canals free of bacteria. The results of this study indicate NiTi rotary and stainless-steel hand K-file step-back instrumentation techniques were not significantly different in their ability to reduce intracanal bacteria.     

Th1 response in Salmonella typhimurium-infected mice with a high or low rate of bacterial clearance

Previous studies have shown that the capacity to clear an attenuated strain of Salmonella typhimurium after the second week of infection varies widely among mouse strains. Bacterial clearance is mediated by CD4+ T cells and is regulated in part by the H-2 complex. The aim of the present study was to compare the patterns of cytokine mRNA expression in the spleens of C57BL/6 (H-2b) and CBA (H-2k) mice, which exhibit a low and a high rate of bacterial clearance, respectively. A transient increase in interleukin-12 (IL-12) mRNA levels was found in both mouse strains. Gamma interferon (IFN-gamma) gene expression was higher and more sustained in C57BL/6 than in CBA mice. No increase in IL-4 mRNA was detected. A transient increase in IL-10 mRNA was found in C57BL/6 mice. Separation of spleen cells into CD4+ and CD4- fractions showed that CD4+ T cells produced the bulk of IFN-gamma in both mouse strains and of IL-10 in C57BL/6 mice. Infection of H-2 congenic mice induced a higher level of IFN-gamma mRNA expression by CD4+ T cells in mice with a low rate of clearance (H-2b) than in mice with a high rate of clearance (H-2q). Treatment of infected C57BL/6 mice with anti-IFN-gamma or anti-CD4 monoclonal antibodies indicated that IFN-gamma participates in resistance in the early phase of infection, but not in bacterial clearance, and that CD4+ T cells mediate bacterial clearance during the 3rd week of infection. Taken together, these results suggest that defective bacterial clearance in H-2b mice is not linked to defective IFN-gamma production and that CD4+ T cells mediate bacterial clearance by an IFN-gamma-independent mechanism.     

Adjacent-segment degeneration after lumbar fusion with instrumentation: a retrospective study

Adjacent-segment degeneration is a known consequence of spinal fusion. Factors associated with this, and its effect on results, have not been well identified. This study sought to determine factors associated with adjacent-segment degeneration and the effect this degeneration has on results after lumbar fusion and instrumentation. Forty-nine patients were retrospectively reviewed after lumbar fusion with instrumentation and analyzed for adjacent-segment degeneration. Adjacent-segment degeneration occurred in 17 (35%) patients and was associated with increasing patient age, the use of interbody fusion, and a worsening of clinical results with time. In older patients with stenosis, it was associated with previous surgery. This should be considered when choosing operative techniques in treating lumbar pathologic conditions, especially in older patients.     

Unusual complication of self-catheterization in a patient with a continent stoma

The authors report a case of acute urinary retention due to a knot in the the catheter, in a patient performing self-catheterization. They describe a simple technique for emergency relief of retention, by creating additional apertures in the catheter, and then discuss the preventive measures of this type of complication.     

Severe aplastic anemia as a complication of treatment with metizol

Aplastic anemia is the rare hematologic complication of the antithyroid medication. We present here the case of 39-years old female who was treated with Thiamazole due to Graves disease. This and the others cases cited in the literature indicate that antithyroid drugs-induced aplastic anemia is characterised by severe clinical status and profound marrow hypoplasia or aplasia but good prognosis with short term recovering.     

Massive hemoptysis as a rare complication in a patient with cystic fibrosis

A female patient, 28 years old, with massive haemoptysis as a complication of cystic fibrosis, is described. Cystic fibrosis is a systemic disease with common pulmonary manifestations. Chronic inflammatory process causes the proliferation of bronchial arteries, and their erosion is followed by bleeding. Transitory haemoptysis is common in patients with cystic fibrosis, but massive haemoptysis is a rare complication of this disease.     

宏观摩擦仪器引起不确定度的分析处理

在摩擦学中,摩擦系数与磨损率都是通过实验得到的,本文的工作旨在研究与这两个参数估算相关的测量不确定度。文中特别采用了一个标准的销-盘摩擦计,其上的两个销固定在同一端面。针对不同的负载、滑动距离和测试时间,总共进行了20次测试,测试时环境温度和相对湿度需保持恒定,测试后使用触针式轮廓仪来获得磁盘截面的磨损疤痕剖面,通过测量磨损痕迹截面及平均磨损体积得到磨损率。实验结果表明,载荷测量时的不确定度对摩擦系数和磨损率的评估有很大的影响,所获得的信息对于优化实验装置和/或开发适当的程序以降低测量不确定度是十分有用的。