Saccular Aneurysm of the Azygos Anterior Cerebral Artery: Three Case Reports

The azygos anterior cerebral artery, a rare anomaly in the circle of Willis in which only a single vessel supplies the medial aspects of both anterior cerebral hemispheres, is closely associated with saccular aneurysms. We present three cases of azygos anterior cerebral artery aneurysms among the 781 cerebral aneurysms surgically treated at our institution in an 11-year period. These three cases all involved elderly women who presented with subarachnoid hemorrhage. Conventional cerebral angiography and CT angiography revealed small saccular aneurysms at the distal ends of the azygos anterior cerebral arteries. These aneurysms were clipped successfully using a bifrontal interhemispheric approach. Hence, the pathogenesis of these particular aneurysms relating to hemodynamic change, associated anomalies, and surgical pitfalls is discussed with review of literature.     

颈椎后纵韧带骨化症前路手术的多因素分析

[目的]探讨影响颈椎后纵韧带骨化症前路手术疗效的相关因素。[方法]48例颈椎后纵韧带骨化症患者，行前路手术治疗，随访1～4年，平均2．1年。根据术后神经功能JOA评分改善率，将患者分为预后良好、预后不佳2组。采用多元Logistic回归分析患者年龄、性别、神经功能、症状持续时间、合并糖尿病、Pavlov值、椎管狭窄率、骨化物分型、CT双影征、脊髓高信号、手术范围以及骨化物处理对患者手术疗效的影响。[结果]骨化物的处理方式是影响患者疗效的唯一因素（P=0．0067）。[结论]前路手术彻底切除骨化之后纵韧带，对脊髓充分减压是前路手术治疗颈椎后纵韧带骨化症的关键。     

The effect of central corneal thickness on estimates of the anterior chamber depth

Background: The slitlamp can be used to estimate the anterior chamber depth (ACD). The length of a slit object is increased until the corneal and iris/lens images appear to just touch. Multiplying the just‐touching‐slit‐length (JTSL) by a conversion factor gives an estimate of the ACD as measured by ultrasonography. The purpose of this study was to determine if central corneal thickness (CCT) affects the accuracy of this technique. Methods: The ACD of 50 subjects was measured by A‐scan ultrasonography and estimated by the slitlamp technique. CCT was measured by ultrasonic pachometry. The refractive error was determined subjectively. Results: The average ultrasonographic ACD for all subjects was 3.32 ± 0.65 mm. The average JTSL was 2.46 ± 0.38 mm. The conversion ratio between the ultrasonographic ACD and the average JTSL was 1.35. The predicted ACD using the regression equation of JTSL on the ultrasound anterior chamber depth (USACD) was 3.32 ± 0.54 mm. The corresponding value using the regression equation of JTSL and CCT on USACD was exactly the same, that is, 3.32 ± 0.54 mm. Conclusion: Incorporation of CCT into a regression equation does not improve the accuracy of the Smith technique.     

Ⅰ期前后路手术治疗下颈椎骨折脱位

目的 评价Ⅰ期前后路手术治疗下颈椎骨折脱位伴关节突绞锁的可行性和近期临床效果.方法 对27例下颈椎骨折脱位伴关节突绞锁的患者,Ⅰ期行后路复位和前路减压植骨内固定术,定期X线摄片观察损伤节段的稳定性和融合率,观察有无并发症发生,以ASIA分级判定脊髓功能的恢复情况.结果 随访6～32个月(平均21.5个月),27例患者均获得了完全复位,损伤节段稳定,颈椎高度和生理曲度维持良好,融合率为100%,内固定位置良好,无植骨块脱出或钢板、螺钉松动、断裂等并发症,脊髓功能平均提高1.4级,无一例患者出现神经症状加重.结论 Ⅰ期前后路手术治疗下颈椎骨折脱位伴关节突绞锁可获得满意的复位、彻底的减压和即刻稳定性的重建,有利于脊髓功能的恢复,近期临床疗效满意.     

Disorders of perfusion of the anterior segment of the eye

Background: We have investigated the vascular perfusion of a wide variety of conditions of the anterior segment using fluorescein angiography.
Methods: The conditions were classified and findings reported according to the system set out below. Patients underwent full ocular examination. Fluorescein angiography of the anterior segment was carried out when indicated to investigate iris atrophy and neovascularisation. Specular microscopy of the corneal endothelium was used to detect changes in this tissue.
Results: The hypoperfusion was variable in degree and accompanied by varying degrees of iris hypoplasia and atrophy with neovascularisation. The degree of neovascularisation depended upon its rapidity of development, the pre-existing state of vascular perfusion and the underlying pathological condition.
Conclusions: Hypoperfusion with resultant ischaemia and neovascularisation is common in conditions of the anterior segment. An understanding of the changes is valuable in treating many conditions affecting the anterior segment. The changes observed may also occur elsewhere in the physical system and may be a significant part of the ageing process, either as scattered, disparate processes or as part of a general disease process.     

Assessment of the invasive potential of human gynecological tumor cell lines with the in vitro Boyden chamber assay: influences of the ability of cells to migrate through the filter membrane

The Boyden chamber assay is widely used for in vitro measurement of the invasive capacity of cells. However, results can be affected significantly if certain precautions are not taken. Using the Boyden chamber assay we investigated in vitro the invasive potential of a variety of human gynecological tumor cell lines to degrade and migrate through the artificial basement membrane matrix Matrigel. However, in the absence of this Matrigel layer large differences were observed in the ability of cells to adhere to, migrate through and attach to the lower side of the filter membranes. These differences were influenced by cell density, degree of directional locomotion, and the size of the filter pores. To adjust for these influences (which are not directly correlated to the capacity of cells to traverse the Matrigel layer), invasion results were corrected for the ability of cells to migrate through the filter membrane. In addition, the invasion of MDA-MB-231 cells was used as an internal standard to compensate for variations in the Matrigel layer between different experiments. Overall, in our experimental set up, the five human breast cancer cell lines were the most invasive (mean invasion ± SEM relative to MDA-MB-231 invasion: 104.7 ± 6.1%), the five human ovarian cancer cell lines the least invasive (60.2 ± 2.2%) and the six human endometrial cancer cell lines showed an intermediate capacity (79.1 ± 3.5%). In conclusion, the Boyden chamber assay can be used reliably for studying the invasive potential of cells in vitro, if the ability of the cells to migrate through the filter is taken into account, and a reference cell line is included to enable comparison of the data obtained from independently performed experiments on different cell lines.     

下丘脑前部注射微量神经降压素对大鼠减压反应的影响

直接将神经降压素注射于大鼠下丘脑前部一侧减压区后,再以电刺激该区,观察其对减压反应的影响。结果表明,注射微量神经降压素后,可使电刺激该区所出现减压反应的最低值和持续时间,都比注射前明显增大。这证明,神经降压素参与电刺激大鼠下丘脑前部一侧减压区所出现的减压反应过程。     

Estimation of instantaneous flow from the indicator-dilution curve after bolus injection of indicator

The indicator-dilution technique is commonly used to determine mean flow estimates. The estimation of instantaneous flow from the shape of an indicator-dilution curve is the objective of this study. Based on a mixing chamber approach to the flow system, a mathematical relationship is derived to reconstruct momentary flow from an indicator-dilution curve. This relationship is verified in a model setup both with only constant flow and with a sinusoidal flow variation superimposed. This method proved to give good flow estimates for limited values of flow parameters. Also, some preliminary experiments were performed in a pulsating flow system simulating heart action. The results were promising although the method proved to be very sensitive to baseline offset.