Diagnostic imaging of tibial periosteal ganglion

A case of a soft tissue tumor situated in the anterior surface of the proximal end of the tibia in an adult patient is demonstrated by conventional radiographs, CT, and MRI. The lesion was well defined with respect to the adjacent soft tissue. The CT exam showed a soft tissue mass with external cortical erosion and thick spicules by periosteal reaction. On T1-weighted images the mass was homogeneous and of low signal intensity, whereas on T2-weighted images it showed a high signal intensity, with some septa in the mass. The differential considerations include a periosteal chondroma, a lipoma, a subperiosteal hematoma, an inflammatory process, a giant cell tumor of tendon sheath, and a parosteal osteosarcoma. The CT and MR features of these entities are reviewed as an aid in differential diagnosis of the periosteal ganglion. Received 24 July 1995; Revision received 19 February 1996; Accepted 21 February 1996     

Modeling the repetitive firing of retinal ganglion cells

A kinetic model for the repetitive firing of retinal ganglion cells were synthesized from voltage-clamp data and evaluated by comparison with whole cell recordings from ganglion cells in the intact tiger salamander retina. Five distinct channels were included in the model and were sufficient to describe the physiologically observed frequency/current relationship in response to various levels of cell depolarization.     

Periosteal ganglion: a report of three new cases including MRI findings and a review of the literature

 Objective. To clarify the clinicopathological features of periosteal ganglion. Design. Three patients with periosteal ganglion were studied clinicopathologically. Patients. One patient was selected from the files of our institute and two from a consultation file. Results and conclusions. All three lesions were located over the medial aspect of the tibia. Plain radiographs showed cortical erosions of varying degrees and mild periosteal reaction of the medial side of the tibia. MR images demonstrated well-circumscribed lesions overlying the cortical bone of the tibia, shown as low-intensity areas on T1-weighted images. On T2-weighted images, lesions were homogeneous, lobulated, and showed a characteristic markedly increased signal intensity. These findings are helpful in making a diagnosis of periosteal ganglion. Each patient had an uneventful clinical course after an excision involving the wall of the ganglion, the adjoining periosteum, and the underlying sclerotic cortical bone.     

Vagal responses induced by endocardial left atrial autonomic ganglion stimulation before and after pulmonary vein antrum isolation for atrial fibrillation

BACKGROUND: Elimination of vagal inputs into the left atrium (LA) may be necessary for successful catheter ablation of atrial fibrillation (AF). These vagal inputs are clustered in autonomic ganglia (AG) that are close to the pulmonary vein antrum (PVA) borders, but whether standard intracardiac echocardiography (ICE)-guided PVA isolation (PVAI) affects these inputs is unknown. OBJECTIVE: The purpose of this study was to assess whether standard ICE-guided PVAI affects vagal responses induced by endocardial AG stimulation in the LA. METHODS: Twenty consecutive patients undergoing first-time PVAI (group 1) and 20 consecutive patients undergoing repeat PVAI for AF recurrence (group 2) were enrolled in the study. Before ablation, electrical stimulation (20 Hz, pulse duration 10 ms, voltage range 12-20 V) was performed through an 8-mm-tip ablation catheter. Based on prior data, regions around all four PVA borders were carefully mapped and stimulated to localize AG inputs. A positive stimulated vagal response was defined as atrioventricular (AV) block, asystole, or increase in mean RR interval by >50%. Locations of positive vagal responses were recorded wth biplane fluoroscopy and CARTO. All patients then underwent standard ICE-guided PVAI by an operator blinded to the locations of vagal responses. Stimulation of the AG locations was then repeated postablation. RESULTS: Patients (age 54 +/- 11 years, 30% female, ejection fraction 54% +/- 7%) had a history of paroxysmal (75%) and persistent (25%) AF. In group 1, vagal responses were induced in all 20 patients around a mean of 3.8 +/- 0.4 PVAs per patient. The most common response was asystole (53%), mean RR slowing >50% (28%), and AV block (20%). Postablation, vagal responses could no longer be induced in all 20 patients. A diminished response was induced (RR slowing <50%) in 2/20 patients around one PVA each. In group 2, vagal responses were not induced in any of the 20 repeat patients. Stimulation capture postablation was confirmed because transient, nonsustained (<30 seconds) AF or atrial flutter was induced in all 40 patients with stimulation, whether vagal responses were induced or not. CONCLUSIONS: Standard ICE-guided PVAI eliminates vagal responses induced by AG stimulation. Responses are not seen in patients presenting for repeat PVAI, despite clinical recurrence of AF.     

三叉神经半月节射频热凝术治疗三叉神经痛50例

目的观察在C形臂引导下经皮穿刺卵圆孔三叉神经半月节射频热凝治疗原发性三叉神经痛的穿刺成功率及临床效果。方法选择原发性三叉神经痛第Ⅱ、Ⅲ支患者50例,以患者颅底CT片确定卵圆孔位置,C形臂下以颞颌关节和瞳孔中点矢状线为参照物引导穿刺卵圆孔三叉神经半月节,以60℃～76℃行射频热凝治疗3.5～5 min。结果所有患者均成功穿刺卵圆孔三叉神经半月节,治疗后7d有效率96%(48/50例),随访4个月未见复发者。未发现明显的严重并发症。结论C形臂引导下经皮穿刺卵圆孔三叉神经半月节射频热凝治疗原发性三叉神经痛穿刺成功率高、疗效确切、安全性高。     

右侧星状神经节阻滞对疼痛兔脉搏血氧饱和度的影响

目的观察右侧星状神经节阻滞(SGB)对急性疼痛兔脉搏血氧饱和度(SpO_2)的影响。方法16只日本大耳白兔暴露右侧星状神经节(SG),置入并固定导管备星状神经节阻滞(SGB)用。手术1周后用甲醛皮下注射法建立急性疼痛模型,随机分为对照组(A组)和SGB组(B组),每组8只。致痛60 min后,B组经导管注入0.25%布比卡因0.5 ml,A组用等量的生理盐水。观察致痛前(T_0)、致痛后10 min(T_1)、30 min(T_2)、60 min(T_3)及应用布比卡因或生理盐水后10 min (T_4)、30 min(T_5)、60 min(T_6)时SpO_2、呼吸频率(RR)和心率(HR)的变化。结果致痛前两组spO_2、RR和HR无差别,致痛后两组RR、HR均增快,在T_1时达高峰,T_2、T_3时略为减慢,与致痛前相比差异有统计学意义(P<0.01),但两组间无明显差别;应用布比卡因或生理盐水后,SpO_2在各点变化不明显,RR亦无明显改变,A组应用生理盐水后HR无明显改变,B组用布比卡因后HR明显减慢(P<0.05)。结论右侧星状神经节阻滞可明显减慢心率,但对血氧饱和度和呼吸频率无明显影响。     

星状神经节阻滞对桡骨骨折患者骨折愈合的影响

目的研究星状神经节阻滞（SGB）治疗对上肢桡骨骨折愈合的影响。方法选择闭合型桡骨横断骨折患者60例,年龄20～45岁,ASAⅠ～Ⅱ级。无其他器质性疾病和代谢性疾病,随机分为2组（n=30）,即SGB组和对照组。SGB组于切开复位内固定术后第2日开始至第14日,应用0.33%罗哌卡因6 ml行SGB治疗,隔日1次,共6次。于术后第14至第42日每隔2日1次,共8次。对照组术后除用骨肽、二代头孢类抗生素等常规治疗外,不进行SGB治疗。于术后第7日监测SGB组患者SGB后10、20、30、40、50、60 min时患侧桡动脉血流峰值速度及双前臂皮肤温差,以及对照组同时点数值。两组患者均于术后第14、28、42日拍摄X线片观察骨折愈合情况并进行分级评分;测定两组患者术后第1、14、28、42日血清中转化生长因子-β1TGF—β1）浓度的变化。结果SGB治疗后,SGB组各时点患侧桡动脉的收缩期血流峰值速度均明显高于对照组（P〈0.01）。SGB组各时点患、健侧皮肤温差明显高于对照组（P〈0.01）。X线片示第14日时两组间骨折愈合评分差异无统计学意义;第28日时,SGB组X线片评分明显高于对照组（P〈0.05）;第42日时,SBG组评分明显高于对照组及28 d时（P〈0.01）。术后第14、28、42日时,两组患者的TGF-β1浓度均高于术后第1日（基础值）（P〈0.01）,其中28d时高于14及42 d时,而SGB组各时点的TGF-β1度均高于对照组（P〈0.01）。结论SGB治疗可促进上肢桡骨骨折愈合。     

Ganglion of the groin in a child: an unusual cause of soft-tissue swelling of the groin

A case of groin ganglion with asymptomatic compression of the femoral vein is described. A 2-year-old girl was referred because of a symptomless groin mass. A mass was palpable in the right femoral triangle. Computed tomography and ultrasonography revealed a cystic lesion compressing the femoral vein ventrally. Prompt surgical removal of the cystic lesion was done without complications. Histopathological examination showed a benign structure similar to that of a ganglion.