腰椎间盘病变致下腰痛的MRI诊断

目的探讨MRI在腰椎间盘病变致下腰痛诊断中的应用价值。方法从腰椎间盘MRI检查体检人群中,挑选出无临床症状者40例,有临床症状者66例,并对每位MRI影像资料进行分析,记录腰椎间盘的表现,包括:椎间盘退变、膨出、脱出、突出游离及椎间盘与神经根的关系、T2WI上纤维环高信号区(high-intensity zone,HIZ)。结果 66例有下腰痛症状者中椎间盘膨出14例(21.2%),椎间盘突出12例(18.2%),椎间盘纤维环出现HIZ15例(22.7%),椎间盘髓核脱出24例(36.3%),有椎间盘髓核游离及神经根受压者见1例(1.5%)。40例无症状者中腰椎间盘退变30例(75%),椎间盘膨出18例(45%),椎间盘突出9例(22.5%),椎间盘纤维环出现HIZ5例(12.5%),椎间盘髓核脱出1例(2.5%),没有发现椎间盘髓核游离及神经根受压者。结论有下腰痛症状者中椎间盘膨出、突出、椎间盘纤维环出现HIZ、椎间盘髓核脱出游离及神经根受压较常见。无症状人群中MRI发现椎间盘退变、膨出、突出及纤维环撕裂较常见,而椎间盘脱出、游离及神经根受压较少见。     

MRI矢状位及轴位参数与退变性腰椎不稳的相关性

目的 分析MRI矢状位及轴位参数与退变性腰椎不稳的相关性.方法 选择本院2018年11月～2020年10月收治的123例腰痛患者作为研究对象,根据是否存在腰椎不稳分为稳定组73例和不稳组50例,均进行MRI矢状位及轴位扫描.比较两组的腰骶角、黄韧带厚度、小关节积液宽度、腰椎间盘退变分级、小关节退变分级.结果 稳定组的腰骶角、黄韧带厚度、小关节积液宽度显著低于不稳组,差异均有统计学意义(P<0.05).稳定组的腰椎间盘退变程度显著低于不稳组,差异有统计学意义(P<0.05).稳定组的小关节退变程度显著低于不稳组,差异有统计学意义(P<0.05).Pearson相关分析显示,腰骶角、黄韧带厚度、小关节积液宽度、腰椎间盘退变分级、小关节退变分级均与退变性腰椎不稳呈正相关(P<0.05).结论 MRI矢状位及轴位参数与退变性腰椎不稳有显著相关性,临床可根据患者腰骶角、黄韧带厚度等对退变性腰椎不稳进行防治.     

腰椎椎间盘退变的临床及实验室评价方法研究进展

正随着人口老龄化的发展,腰椎退变性疾病日益多见,主要包括椎间盘、骨质、小关节突、周围韧带以及软组织等的退变,其中引起腰痛的主要原因是腰椎椎间盘的退变。腰椎椎间盘退变的原因十分复杂,主要为遗传易感性、衰老、机械负荷及营养供应障碍因素的共同作用[1]。早期评价腰椎椎间盘退变状况对进一步明确退变机制、选择合适的治疗方案以及评价治疗效果有重要作用,近年来有关腰椎椎间盘退变的各种评价方法的改良和应用越来越受重     

大鼠腰椎间盘退变模型的MRI及病理学观察

目的研究大鼠腰椎间盘退变模型的MRI表现及病理学改变。方法随机选取32只SD大鼠,分为实验组和对照组,每组各16只。实验组采用手术方法以L3为中心切除相关腰椎的棘突、关节突、棘上韧带棘间韧带,切断双侧竖棘肌。通过改变脊柱的生物力学制作腰椎问盘退变动物模型。对照组仅切开皮肤后即缝合。术后分别于1个月、2个月、3个月行MRI检查,之后处死行病理学观察。结果MRI检查结果对照组：无特异性改变,实验组：于术后2个月、3个月时的T2信号明显降低。病理学检查对照组：无明显变化,实验组：表现为髓核细胞减少,外周纤维环结构紊乱。结论本实验方法的建立为研究腰椎间盘退变提供了比较理想的动物模型。     

髂骨转移癌误诊腰椎间盘突出症一例

患者，女，46岁，因右下肢疼痛、麻木、无力并间歇性跛行半年入院，入院前在外院行腰椎CT片示：L4、5、L5S1椎间盘膨出，L5S1层面右侧神经根轻度受压，硬膜囊未见受压；腰椎MRI示：腰椎退变，椎间盘变性，L4、5、L5S1椎间盘膨出。在外院考虑腰椎间盘突出症行非手术治疗一个月无明显疗效，建议患者手术治疗。然后转入我院时查体：腰背     

MRI STIR序列在四肢关节隐匿性骨折中的诊断价值

目的探讨MRISTIR序列在四肢关节隐匿性骨折诊断中的应用价值。方法收集四肢关节隐匿性骨折患者19例行MRI常规SE序列T1WI及T2WI、FFE和STIR-T2WI多序列检查,比较各序列显示隐匿性骨折的差异。结果本组19例隐匿性骨折患者MRI主要表现及检出率分别为：SE序列T1WI检出线样低信号骨折线11例（57.8%）,小片状低信号骨挫伤12例（63.1%）;T2WI检出稍低信号骨折线4例（21.1%）,小片状等高信号骨挫伤1例（5%）;FFE序列检出模糊稍高线样骨折6例（31.5%）,模糊稍高信号小片状影2例（10.5%）,STIR序列检出线样高信号影16例（84.2%）,小片状高信号影19例（100%）。骨挫伤骨髓水肿检出率STIR序列高于SET1WI,SET1WI高于T2WI、FFE系列。结论磁共振STIR序列对四肢关节隐匿性骨折的诊断敏感性较高,特别易于显示以骨挫伤为主要表现的Ⅰ型隐匿性骨折,是明确诊断的最佳序列。     

陆军驾驶兵下腰痛的类型与防治

目的研究陆军汽车驾驶兵下腰痛病因、类型、预防及治疗方法。方法对我院五年来,收治的患有下腰痛的陆军某部2000名汽车驾驶兵进行分析,并给予综合的康复治疗及出院康复指导。结果 2000例中,急性腰肌扭伤256例,慢性腰肌劳损505例,腰背肌筋膜炎240例,第三腰椎横突综合征170例,腰椎间盘突出症359例,腰椎小关节紊乱320例,棘上韧带、棘间韧带损伤85例,腰椎退变性滑脱65例,康复理疗及综合保守治疗1966例,手术治疗34例。腰痛治愈1765例,显效112例,有效89例,总有效率98.3%。结论陆军汽车驾驶兵下腰痛与特殊军事训练有关,主要为长时间的坐姿及颠簸所致急慢性腰肌损伤,椎间盘退变为主要病因,其次为椎体间小关节,韧带的退变所致的疼痛。对陆军驾驶兵下腰痛进行及时、准确的治疗,依靠正确的判断及准确的分型,提高了陆军汽车驾驶兵的战斗力。     

核磁共振对产后骶髂关节炎的诊断价值

目的探讨核磁共振(MRI)在产后骶髂关节炎诊断中的价值。方法回顾分析17例产后骶髂关节痛的MRI的影像学表现。17例双侧骶髂关节T1WI、T2WI、STIR序列扫描。结果 17例均为单侧骶髂关节受累,15例关节旁骨髓T1WI低信号、T2WI、STIR高信号;10例T1WI滑膜部关节软骨内出现混杂信号;13例T1WI、T2WI骨板信号增高;10例关节囊及附着点、周围软组织STIR呈高信号。结论结合病史及MRI影像改变,MRI能对产后骶髂关节炎做出早期诊断。     

颈椎挥鞭样损伤的MRI特征与临床意义

[目的]探讨颈椎挥鞭样损伤的MRI表现及其诊断价值.[方法]对30例手术治疗的急性颈椎挥鞭样损伤纳入研究,以手术结果为参照,从椎前筋膜、前纵韧带、椎间盘、椎骨、后纵韧带、颈髓、颈后韧带复合体、颈椎稳定性方面回顾性分析其MR表现.[结果]椎前筋膜出血水肿(27例,90％),MRI上表现为椎前筋膜增厚肿胀伴信号改变,于T1WI序列上呈稍低信号、等信号或稍高信号,于T2WI及STIR序列上呈高信号;颈椎前纵韧带断裂(27例,90％),手术显示47个断裂平面,MRI上27例显示33个断裂平面(70.2％),表现为线状或斑点状异常信号改变,T1WI序列上等信号、T2WI及STIR序列上高信号;椎间盘损伤(30例,100％),MRI显示形态信号改变;颈椎骨折(6例,20％),MRI全部显示;颈椎后纵韧带断裂(12例,40％),手术显示15个断裂层面,MRI上显示8例11个断裂层面(73.3％),表现为线状或斑点状异常信号改变,T1WI序列上等信号、T2WI及STIR序列上高信号;MRI上还显示颈椎骨挫伤(4例,13.3％);颈椎不稳(25例,83.3％);颈髓损伤(25例,83.3％);颈后韧带复合体损伤(25例,83.3％).[结论]颈椎挥鞭样损伤的MRI表现具有重要的临床诊断价值,与临床表现相结合可为临床诊断与治疗提供影像学依据.     

腰椎间盘突出症与周围韧带的关系及组织学观察

目的：进一步了解腰椎周围软组织病变与腰椎间盘突出症之间的关系,探讨腰椎病变的病因。方法：测量31例手术取得的黄韧带和椎板的厚度,对取得的标本进行组织学观察。结果：腰椎病变处的黄韧带和椎板明显增厚,韧带组织伴有纤维轻骨化,胶元纤维排列紊乱,结论：除了外伤外,棘上韧带和黄韧带的退变是腰椎间盘脱出重要的发病因素。     

Vasopressor hormone response following mesenteric traction during major abdominal surgery

Background : We investigated the vasopressor hormone response following mesenteric traction (MT) with hypotension due to prostacyclin (PGI₂) release in patients undergoing abdominal surgery with a combined general and epidural anesthesia. Methods : In a prospective, randomized, placebo-controlled study we administered 400 mg ibuprofen (i.v.) in 42 patients scheduled for abdominal surgery. General anesthesia was combined with epidural anesthesia (T4-L1). Before as well as 5, 15, 30, 45, and 90 min after MT we recorded plasma osmolality, hemodynamics and measured 6-keto-PGFlα (stabile metabolite of PGI₂), TXB₂ (stabile metabolite of thromboxane A₂) active renin, and arginine vasopressin (AVP) plasma concentrations by radioimmunoassay. Catecholamine levels were assessed by high-pressure liquid chromatography (HPLC) with electrochemical detection. Results : Following MT, arterial hypotension occurred along with a substantial PGI₂ release. This was completely abolished by ibuprofen administration. Although plasma levels of 6-keto-PGF_1α (1133 (708) vs. 60 (3) ng/L, median (median absolute deviation), P=0.0001, placebo vs. ibuprofen) remained significantly elevated, blood pressure was restored within 30 min after MT in the placebo group. At the same point in time plasma concentrations of TXB² (164 (87) vs. 58 (1) ng/L, P=0.0001), epinephrine (46 (33) vs. 14 (6) ng/L, P=0.001), AVP (41 ± (18) vs. 12 (7) ng/L, P=0.0004), and active renin (27 (12) vs. 12 (4) ng/L, P = 0.001) were significantly higher in placebo-treated patients. Conclusion : Under combined general and epidural anesthesia arterial hypotension following MT due to endogenous PGI₂ release is associated with enhanced release of AVP, active renin, epinephrine and thromboxane A₂, presumably contributing to hemodynamic stability within 30 min after MT.     

A Teaspoon Pump for Pumping Blood with High Hydraulic Efficiency and Low Hemolysis Potential

Abstract: Virtually all blood pumps contain some kind of rubbing, sliding, closely moving machinery surfaces that are exposed to the blood being pumped. These valves, internal bearings, magnetic bearing position sensors, and shaft seals cause most of the problems with blood pumps. The original teaspoon pump design prevented the rubbing, sliding machinery surfaces from contacting the blood. However, the hydraulic efficiency was low because the blood was able to "slip around" the rotating impeller so that the blood itself never rotated fast enough to develop adequate pressure. An improved teaspoon blood pump has been designed and tested and has shown acceptable hydraulic performance and low hemolysis potential. The new pump uses a nonrotating "swinging" hose as the pump impeller. The fluid enters the pump through the center of the swinging hose; therefore, there can be no fluid slip between the revolving blood and the revolving impeller. The new pump uses an impeller that is comparable to a flexible garden hose. If the free end of the hose were swung around in a circle like half of a jump rope, the fluid inside the hose would rotate and develop pressure even though the hose impeller itself did not "rotate"; therefore, no rotating shaft seal or internal bearings are required.     

Microspheres Based Detoxification System: A New Method in Convective Blood Purification

Abstract: A variety of protein-bound or hydrophobic substances, accumulating as a result of pathologic conditions such as exogenous or endogenous intoxications, are removed poorly by conventional detoxification methods because of low accessibility (hemodialysis), insufficient adsorption capabilities (hemosorption), low efficiency (peritoneal dialysis), or economic limitations (high-volume plasmapheresis). Combining advantages of existing methods with microspheric technology, a module-based system was designed. Major operating parameters of the latter can be modified to allow for adjustment to individual clinical situations. An extracorporeal blood circuit including a plasmafilter is combined with a secondary high-velocity plasma circuit driven by a centrifugal pump. Different microspheric adsorbers can be combined in one circuit or applied in sequence. Thus, a prolonged treatment can be tailored using specially designed selective adsorber materials. Comparing this system with existing methods (high-flux hemodialysis, molecular adsorbent recycling system), results from our in vitro studies and animal experiments demonstrate the superior efficiency of substance removal.     

Is the recovery profile of mivacurium independent of the rate of decay of its plasma concentration in patients with normal plasma cholinesterase activity?

Background: The duration of action of muscle relaxants is poorly correlated to the rate of decay of their plasma concentration. The plasma concentration of mivacurium may rapidly decrease below its active concentration because of the extensive hydrolysis of mivacurium. By inflating a tourniquet on one upper limb for 3 min after the administration of atracurium, mivacurium or vecuronium, we studied the influence of the initial decline of their plasma concentration on their effect. Methods: In 50 patients anaesthetised with thiopental, isoflurane and fentanyl, the effect of bolus doses of 0.15 or 0.25 mg . kg^?1 mivacurium (MIV 15, MIV 25), 0.3 or 0.5 mg . kg^?1 atracurium (ATR 30, ATR 50) and 0.06 or 0.1 mg . kg^?1 vecuronium (VEC 06, VEC 10) were measured on both arms (evoked response of the adductor pollicis to train-of-four stimulation every 12 s), a tourniquet being applied on one arm just before and during 3 min after the muscle relaxant bolus. Results: Tourniquet inflation of 3 min almost abolished the neuromuscular effect of mivacurium. In the vecuronium groups and in the ATR 50 group, tourniquet inflation did not modify the maximum degree of depression of the twitch response. Also, the duration of action of vecuronium was unaffected by the tourniquet. In the ATR 30 group, times to return of the twitch response to 25% (duration 25%) and 75% (duration 75%) of control response were significantly shorter in the cuffed arm, 23 min vs 27 min, and 41 min vs 45 min, respectively. In the ATR 50 group, only duration 25% was significantly shorter in the cuffed arm (41 min vs 45 min). Conclusion: The results suggest that the rate of decline of the plasma concentration of mivacurium is so rapid, that a very low and almost clinically ineffective concentration is present as soon as 3 min after its administration. The results also indicate that the recovery from a mivacurium-induced neuromuscular blockade is not influenced by the rate of decay of its plasma concentration in patients with genotypically normal plasma cholinesterase.     

Membranes in Artificial Organs

Abstract: Membrane processes play a pivotal and enabling role in modern replacement therapy for acute and chronic organ failure and in the management of immunologic diseases. In fact, virtually all contemporary extracorporeal blood purification methods employ membrane devices, and the next generation of artificial organs and tissue engineering therapies are almost certain to be similarly grounded in membrane technology. In this short essay, we comment on the similarities and differences among synthetic membranes and their natural counterparts and also provide a critical overview of the demographics and technology of hemodialysis, hemofiltration, apheresis, oxygenation, and emerging membrane technologies and applications.     

Tissue perfusion in relation to cardiac output during continuous positive-pressure ventilation and administration of propranolol or verapamil

Background : Our objective was to determine whether administration of propranolol or verapamil modifies the hemodynamic adaptation to continuous positive-pressure ventilation (CPPV), in particular the regional distribution of cardiac output (CO).
Methods : General hemodynamics and regional blood flows assessed by microsphere technique (15 (μm) were recorded in 16 anesthetized pigs during spontaneous breathing (SB) and CPPV with 8 cm H₂O end-expiratory pressure (CPPV8) before and after intravenous administration of propranolol (0.3 mg · kg⁻¹ followed by 0.15 mg · kg⁻¹ · h⁻¹, n=8) or verapamil (0.1 mg · kg⁻¹ followed by 0.3 mg · kg⁻¹ · h⁻¹, n=8).
Results : CPPV8 depressed CO by 25% without shifts in its relative distribution with the exception of a noteworthy increase in adrenal perfusion. Propranolol increased arterial blood pressure, and due to a fall in heart rate, CO dropped by 25%. The kidneys and, to a lesser extent, the splanchic region and central nervous system received increased fractions of the remaining CO at the expense of skeletal muscle flow. Similar patterns were seen during SB and CPPV8 such that the combination of propranolol and CPPV8 depressed CO by 50%. The circulatory effects of verapamil were less evident but myocardial perfusion tended to increase.
Conclusions : The combination of propranolol or verapamil with CPPV does not result in any specific hemodynamic interaction in anesthetized pigs, except that the combined effect of propranolol and CPPV may severely reduce CO.     

Volatile anaesthetics reduce adhesion of blood platelets under low-flow conditions in the coronary system of isolated guinea pig hearts

Background : Inhibitory effects of volatile anaesthetics on platelet aggregation have been demonstrated in several studies. However, the influence of volatile anaesthetics on intracoronary platelet adhesion has not been elucidated so far.
Methods : Isolated hearts of guinea pigs were perfused with buffer in the absence or presence of volatile anaesthetics (0.5 and 1 MAC) at constant coronary flow rates of 5 ml/min for 25 min, then 1 ml/min for 30 min and again 5 ml/min for 10 min. Before, during and after low-flow perfusion, a bolus of human platelets was applied into the coronary system. To simulate thrombogenic conditions, 0.3 U/ml human thrombin was infused during low-flow perfusion and reperfusion. The number of platelets sequestered to the endothelium was calculated from the difference between coronary in- and output of platelets. The myocardial production of lactate and consumption of pyruvate and coronary perfusion pressure were also determined.
Results : At a flow rate of 5 ml/min only about 3% of the applied platelets did not emerge from the coronary system, in any group. In contrast, 13.1±1.2% (mean±SEM) of infused platelets became adherent in low-flow perfusion in the control group without anaesthetic. The adherence was reduced with each 1 MAC isoflurane (to 6.2±1.2%), sevoflurane (to 4.4±0.9%) or halothane (to 3.2±1.5%) (each P <0.05 vs. control). Volatile anaesthetic, 0.5 MAC, did not inhibit platelet adhesion to a statistically significant extent in any case. Perfusion pressure and metabolic parameters were not statistically different between the control and the hearts exposed to anaesthetics.
Conclusion : Volatile anaesthetics in a concentration of 1 MAC can reduce the adhesion of platelets in the coronary system under reduced flow conditions. This action does not arise from vasodilation or inhibition of ischaemic stress.     

Bariatric Surgery in Some "Central and East-European (former Eastern bloc)"Countries - Current Status and Prediction for the Next Millennium

Background: Obesity is increasing globallly, including in the formerly "Eastern Bloc" countries. Methods: A survey was made of obesity and bariatric surgery. Results: In the 8 East and Central European countries studied, with total population 300 million, roughly 43% of the population was overweight (BMI 25-30), 23% obese (BMI > 30), with about 15 million people morbidly obese (BMI > 40). From 0-10 morbidly obese individuals/100,000/year undergo bariatric surgery. Conclusion: Most countries were found to provide inadequate treatment for obesity.The majority of the morbidly obese are not treated effectively. However, health-care awareness of obesity and bariatric surgeons are slowly increasing.     

Dilemma of Membrane Biocompatibility and Reuse

Abstract: Numerous articles have been published on the multiple use of dialyzers and on the effect of different reprocessing chemicals and techniques on the dialyzer biocompatibility and performance. The results often appear contradictory, especially those comparing standard biocompatibility parameters. Despite this confusion, a discerning review of the published works allows certain limited conclusions to be drawn. Reprocessing of used hemodialyzers changes the biocompatibility profile of a dialyzer as defined by the parameters complement activation. leukopenia, and cytokine release. The effect of reprocessing depends on the chemicals and reprocessing technique applied and also on the type of membrane polymer being subjected to the reprocessing procedure. Reports of pyrogenic reactions indicate that the flux of the membrane also influences how suitable it is for safe reuse. An increased risk of allergic and pyrogenic reactions appears to be associated with dialyzer reuse. Furthermore, there has been a lack of investigations into the immunologic effect of the layer of adsorbed and chemically altered proteins that remains on the inner surface of reprocessed dialyzers. We conclude that the clinical benefit of dialyzer reuse cannot be generally accepted from a biocompatibility point of view.     

Influence of dopexamine hydrochloride on haemodynamics and regulators of circulation in patients undergoing major abdominal surgery

Background: Catecholaminergic support is often used to improve haemodynamics in patients undergoing major abdominal surgery. Dopexamine is a synthetic vasoactive catecholamine with beneficial microcirculatory properties. Methods: The influence of perioperative administration of dopexamine on cardiorespiratory data and important regulators of macro- and microcirculation were studied in 30 patients undergoing Whipple pancreaticduodenectomy. The patients received randomized and blinded either 2 μg · kg^?1 · min^?1 of dopexamine (n=15) or placebo (n=15, control group). The infusion was started after induction of anaesthesia and continued until the morning of the first postoperative day. Endothelin-1 (ET-1), vasopressin, atrial natriuretic peptide (ANP), and catecholamine plasma levels were measured from arterial blood samples. Measurements were carried out after induction of anaesthesia, 2 h after onset of surgery, at the end of surgery, 2 h after surgery, and on the morning of the first postoperative day. Results: Cardiac index (CI) increased significantly in the dopexamine group (from 2.61±0.41 to 4.57±0.78 1 · min^?1 · m^?2) and remained elevated until the morning of the first postoperative day. Oxygen delivery index (DO₂I) and oxygen consumption index (VO₂I) were also significantly increased in the dopexamine group (DO₂I: from 416±91 to 717±110 ml/m² · m²; VO₂I: from 98±25 to 157±22 ml/m² · m²), being significantly higher than in the control group. pHi remained stable only in the dopexamine patients, indicating adequate splanchnic perfusion. Vasopressive regulators of circulation increased significantly only in the untreated control patients (vasopressin: from 4.37±1.1 to 35.9±12.1 pg/ml; ET-1: from 2.88±0.91 to 6.91±1.20 pg/ml). Conclusion: Patients undergoing major abdominal surgery may profit from prophylactic perioperative administration of dopexamine hydrochloride in the form of improved haemodynamics and oxygenation as well as beneficial influence on important regulators of organ blood flow.