Posterior cortical atrophy: a single case cognitive and radiological follow-up

Posterior cortical atrophy (PCA) is a rare neurodegenerative syndrome characterized by initial predominant visuoperceptual deficits followed by a progressive decline in other cognitive functions. This syndrome has not been as thoroughly described as other dementias, particularly from a neuropsychological evolution perspective with only a few studies describing the evolution of its cognitive progression. In this investigation we review the literature on this rare condition and we perform a 7-year neuropsychological and neuroradiological follow-up of a 64-year-old man with PCA. The subject’s deficits initially appeared in his visuoperceptual skills with later affectation appearing in language and other cognitive functions, this being coherent with the patient’s parieto-temporal atrophy evolution.     

Panic-like defensive behavior but not fear-induced antinociception is differently organized by dorsomedial and posterior hypothalamic nuclei of Rattus norvegicus (Rodentia,Muridae)

The hypothalamus is a forebrain structure critically involved in the organization of defensive responses to aversive stimuli. Gamma-aminobutyric acid (GABA)ergic dysfunction in dorsomedial and posterior hypothalamic nuclei is implicated in the origin of panic-like defensive behavior, as well as in pain modulation. The present study was conducted to test the difference between these two hypothalamic nuclei regarding defensive and antinociceptive mechanisms. Thus, the GABA_A antagonist bicuculline (40 ng/0.2 µL) or saline (0.9% NaCl) was microinjected into the dorsomedial or posterior hypothalamus in independent groups. Innate fear-induced responses characterized by defensive attention, defensive immobility and elaborate escape behavior were evoked by hypothalamic blockade of GABA_A receptors. Fear-induced defensive behavior organized by the posterior hypothalamus was more intense than that organized by dorsomedial hypothalamic nuclei. Escape behavior elicited by GABA_A receptor blockade in both the dorsomedial and posterior hypothalamus was followed by an increase in nociceptive threshold. Interestingly, there was no difference in the intensity or in the duration of fear-induced antinociception shown by each hypothalamic division presently investigated. The present study showed that GABAergic dysfunction in nuclei of both the dorsomedial and posterior hypothalamus elicit panic attack-like defensive responses followed by fear-induced antinociception, although the innate fear-induced behavior originates differently in the posterior hypothalamus in comparison to the activity of medial hypothalamic subdivisions.     

脂肪乳对血液细胞CBC参数及Diff分类参数检测的影响

目的 观察脂肪乳对血液细胞分析结果的影响.方法 在体外将健康志愿者血液样本以及生理盐水与一定比例的脂肪乳混合,配制系列浓度的血液/脂肪乳混合液以及生理盐水/脂肪乳混合液,于血液细胞分析仪上进行测试,观察不同浓度脂肪乳对CBC参数、Diff分类参数的影响.结果 随着脂肪乳浓度的增高,血液/脂肪乳混合液的CBC参数测定值渐进升高,Diff分类参数中的淋巴细胞分类比例呈下降趋势而单核细胞比例逐渐增高；而生理盐水/脂肪乳混合液中白细胞、血红蛋白和PLT-O明显升高.结论 脂肪乳会对血液细胞分析仪多个参数的测定产生影响,可以通过测定结果的一些特征筛选可疑含脂肪乳标本.     

减小后牙▉平面倾斜度对安氏Ⅱ类高角畸形髁突位置影响的研究

目的: 研究在安氏Ⅱ类高角畸形正畸治疗中,减小后牙平面倾斜度对髁突位置的影响。方法: 15例安氏Ⅱ类高角畸形患者,年龄15~30岁。治疗前ANB>5°,下颌平面角FH-MP>32°,磨牙关系为双侧远中关系。常规排齐整平及适当扩弓后,利用多曲唇弓导下颌向前,并使后牙平面平坦化。利用锥形束CT（cone-beam CT,CBCT）测量治疗前、后颞下颌关节前、上、后间隙及后牙平面的改变情况。采用SPSS19软件包对变化量进行t检验;并利用相关性分析,进一步探讨髁突位置改变量与后牙平面倾斜度减小量之间的相关性。结果: 所有患者磨牙尖牙关系均调整到中性,侧貌改善明显,髁突后间隙平均增加(0.88±0.17)mm,变化有统计学意义(P<0.001);髁突上间隙平均增加(0.45±0.20)mm,变化也具有统计学意义(P<0.05)。后牙平面变平坦,POP-SN及POP-FH平均减小3.59°±2.31°及2.31°±3.62°,变化具有统计学意义(P<0.001)。髁突前间隙变化量无统计学意义,髁突位置改变量与后牙平面倾角的变化量之间无显著相关性。结论: 在安氏Ⅱ类高角畸形患者的正畸治疗中,通过正畸减小后牙平面倾斜度,可使髁突的位置发生适当的前下改变,有利于关节症状的改善。     

小脑扁桃体下疝合并脊髓空洞症治疗分析

目的 探讨小脑扁桃体下疝合并脊髓空洞症的治疗.方法 回顾性分析1995年8月至2010年8月经治的29例小脑扁桃体下疝合并脊髓空洞症患者,均采用手术干预治疗,单纯行枕大孔减压术16例,行枕大孔减压加空洞-蛛网膜下腔分流术13例.术后随访6个月～3年观察治疗效果.结果 随访6个月～3年,单纯行后颅窝减压组中显效8例,有效6例,无效2例,恶化0例,总有效率为87.5％;后颅窝减压空洞-蛛网膜下腔分流组中显效6例,有效4例,无效2例,恶化1例,总有效率为76.9％,2组总有效率比较差异无统计学意义（P＞0.05）.结论 手术是小脑扁桃体下疝合并脊髓空洞症的首选治疗,因下疝和空洞致脊髓受损轻者减压术后恢复较好,而脊髓受损明显者则手术效果差.     

The safety of the posterior ankle arthroscopy in management of posterior ankle impingement: A cadaveric study

BackgroundArthroscopic management of the posterior ankle impingement with the patient in supine position has the advantage of dealing with anterior ankle pathology at the same time without the need to change position of the patient. This study aims at evaluation of the safety of portal establishment and instrumentation of this technique.MethodsSixteen fresh-frozen cadaver specimens were used. The relationships of the posteromedial and posterolateral portals to the adjacent tendons and nerves and the relationship of the coaxial portal tract with the posterior ankle capsule and the flexor hallucis longus tendon were studied.ResultAngle θ₁ between the intermalleolar line and the posterior ankle coaxial portal tract averaged 1° (−10° to 22°). Angle θ₂ between the intermalleolar line and the metal rod where the neurovascular bundle started to move averaged 19° (10° to 30°). Angle θ₃ between the intermalleolar line and the metal rod where it reached the lateral border of the Achilles tendon was larger than angle θ₂ in all specimens. The angle of safety (θ_s) averaged 18° (−1° to 26°).ConclusionsInjury to the tendon, nerves or vessels is possible during establishment of the portals and resection of the os trigonum.     

Posterior polar cataract: A review

Posterior polar cataract is a rare form of congenital cataract. It is usually inherited as an autosomal dominant disease, yet it can be sporadic. Five genes have been attributed to the formation of this disease. It is highly associated with complications during surgery, such as posterior capsule rupture and nucleus drop. The reason for this high complication rate is the strong adherence of the opacity to the weak posterior capsule. Different surgical strategies were described for the handling of this challenging entity, most of which emphasized the need for gentle maneuvering in dealing with these cases. It has a unique clinical appearance that should not be missed in order to anticipate, avoid, and minimize the impact of the complications associated with it.     

Tapia's Syndrome after Posterior Cervical Spine Surgery under General Anesthesia

We present a case report to remind surgeons of this unusual complication that can occur in any surgery, even posterior cervical spine surgery under general anesthesia and discuss its causes, treatment methods, and the follow-up results in the literature. The peripheral Tapia''s syndrome is a rare complication of anesthetic airway management. Main symptoms are hoarseness of voice and difficulty of tongue movement. Tapia''s syndrome after endotracheal general anesthesia is believed to be due to pressure neuropathy of the vagus nerve and the hypoglossal nerve caused by the endotracheal tube. To our knowledge, no report has been published or given an explanation for Tapia''s syndrome after posterior cervical spine surgery. Two patients who underwent posterior cervical surgery complained hoarseness and tongue palsy postoperatively. There is no direct anatomical relation between the operation, the vagus nerves and the hypoglossal nerves, and there is no record of displacement or malposition of the endotracheal tube. After several months, all symptoms are resolved. To avoid this problem in posterior cervical spine surgery, we suggest paying special attention to the position of the endotracheal tube to avoid excessive neck flexion before and during the positioning of the patient.