Essential hypertension associated with neurovascular compression: angiographic findings.

According to the hypothesis of Jannetta, an arterial compression of the left root entry zone (REZ) of cranial nerves IX and X by looping arteries could play an important role in the pathogenesis of essential hypertension. In an initial anatomical study, the positions of the left vagus and glossopharyngeal nerves in the skull were radiographically determined in 10 cadavers. By using a pattern of REZ topography developed from this information, the angiographic findings in 107 hypertensive and 100 normotensive patients were then compared retrospectively. In 80% of the angiograms of the hypertensive patients that could be evaluated, an artery crossed the left REZ of cranial nerves IX and X. Most frequently, this was the posterior inferior cerebellar artery (35.3% of cases), followed by the vertebral artery (29.4% of cases) and the anterior inferior artery (19.1% of cases). In 9 cases (13%), both the posterior inferior cerebellar artery and the vertebral artery appeared in the REZ. Frequently, a larger diameter of the left vertebral artery was found. The angiograms of normotensive patients that could be evaluated revealed an artery in the REZ in only 34.5% of cases. Our results support the hypothesis that essential hypertension may be associated with neurovascular compression of the left REZ of cranial nerves IX and X.     

Prevalence of neurovascular compression in patients with essential and secondary hypertension

AIMS: There are discrepant data on the prevalence of vascular compression of the rostral ventrolateral medulla, discussed as a possible cause of essential hypertension, in patients with essential and secondary hypertension. We therefore evaluated the comparative prevalence of neurovascular compression in two large and well defined patient groups with severe essential and secondary hypertension. PATIENTS AND METHODS: 121 patients with long-standing severe (requiring at least three antihypertensive agents for adequate control of blood pressure) essential or secondary hypertension and extensive examination for causes of secondary hypertension were recruited. The presence of neurovascular compression was assessed independently by a neuroradiologist and a neurosurgeon in MRI images for all patients. The subgroup of patients with the highest prevalence of neurovascular compression was identified by CART-analysis. RESULTS: 5 of 121 formerly included patients (4.1%) were excluded for diverging MRI assessments. Neurovascular compression was diagnosed in 50 of 68 patients (73.5%) with essential hypertension and 6 of 48 patients (12.5%) with secondary hypertension. The odds ratio for diagnosis of neurovascular compression in patients with essential hypertension was 19.4 (95%-confidence interval 7.9-47.9) compared to patients with secondary hypertension. CART-analysis identified the highest prevalence of neurovascular compression in patients with severe essential hypertension younger than 67.5 years. CONCLUSIONS: Since successful decompression or implantation of a carotid sinus stimulator in patients eligible for surgery may lead to substantial improvement in blood pressure in patients in whom blood pressure could not be lowered below 140/90 mmHg by antihypertensive treatment alone MRI screening for the presence of neurovascular compression is justified in patients meeting all of the following three criteria: exclusion of secondary hypertension after extensive examination; hypertension uncontrollable with antihypertensive treatment alone, and age younger than 67.5 years.     

The perforating branches of the middle cerebral artery. A microanatomical study

The perforating branches (PFB's) of the middle cerebral artery (MCA) were studied in 34 unfixed brain hemispheres which were injected with a polyester resin and dissected under the operating microscope. Five hundred and eight vessels were identified and their site of origin, branching pattern, outer diameter (OD), and length recorded. Four hundred and two PFB's (79%) originated from the main trunk of the MCA before its division; the remaining 106 vessels (21%) had their origin from branches of the MCA as follows: superior trunk, 43 vessels (8.5%); inferior trunk, 30 vessels (6%); middle trunk, four vessels (0.8%); early temporal branch, 27 vessels (5.3%); and early frontal branch, two vessels (0.4%). The number of PFB's in each hemisphere varied from five to 29 (mean 14.9 +/- 0.7 vessels). The great majority of PFB's (96%) originated along the proximal 17 mm of the MCA. The PFB's arising in the first 10 mm had a mean OD of 0.35 +/- 0.01 mm and a mean length of 9.25 +/- 0.19 mm, and those arising from the second 10 mm had a mean OD of 0.47 +/- 0.02 mm and a mean length of 16.67 +/- 1.4 mm. A clear distinction between a medial and lateral group of PFB's was present in only 14 hemispheres (41%). In nine hemispheres (26%), perforating vessels from the anterior cerebral artery (A1 segment) and from the recurrent artery of Heubner replaced the medial group of PFB's of the MCA. In one case this group originated in an accessory MCA. In three hemispheres (9%) a small anastomosis (OD 0.2 mm) was seen between a PFB of the recurrent artery of Heubner and one of the MCA. From a total of 508 PFB's, 255 vessels (50%) originated as single vessels, while 253 vessels (50%) originated as branches of common stems. The OD of the single vessels ranged from 0.1 mm to 1.1 mm (mean 0.39 +/- 0.02 mm), and the length from 3 to 20 mm (mean 10.8 +/- 0.2 mm). The common stems ranged in OD from 0.6 to 1.8 mm (mean 0.87 +/- 0.04 mm), and in length from 1 to 15 mm (mean 4.1 +/- 0.4 mm). The clinical application of these anatomical data to the management of aneurysms and arteriovenous malformations of the MCA, and in the field of interventional neuroradiology is described. The most frequent pathological entities involving the perforating vessels are also discussed.     

Motion at the modular acetabular shell and liner interface. A comparative study.

Excessive polyethylene debris generated from a total hip arthroplasty can lead to osteolysis and premature revision. Most of this polyethylene debris comes from the concave articulation. However, abrasive wear on the convex side of a modular polyethylene component also may play a role in this problem. Motion of a modular polyethylene liner with respect to its shell can lead to such abrasive wear. Six samples of modular acetabular components from eight manufacturers were tested for motion between the shell and the liner. Motion at the shell liner interface was detected by five fiberoptic sensors in the x, y, and z planes. Micromotion occurred at the shell liner interface in all designs tested. The magnitude of motion varied between manufacturers, ranging from 5 to 311 microns. Design features that limit motion may be advantageous in limiting the amount of polyethylene debris.     

A comparative study of ketanserin and metoprolol in essential hypertension

The role of serotonin in the pathogenesis of hypertension is interesting, and its investigation is much in vogue at present. This study compared the hypotensive effect of ketanserin, a specific 5-hydroxytryptamine receptor antagonist, with metoprolol in essential hypertension. On a double-blind basis, one treatment group (19 patients on ketanserin) was compared with another (21 patients on metoprolol). There was a significant reduction in diastolic blood pressure with both ketanserin and metoprolol (P less than 0,001). Side-effects were insignificant. One patient on metoprolol and 2 on ketanserin complained of dizziness. The dose of ketanserin was 40 mg twice a day and that of metoprolol 100 mg twice a day. Ketanserin does not appear to cause abnormal haematological values or biochemical adverse effects. It can be given to hypertensive patients with cardiac failure or bronchial asthma without adverse effects and may improve the peripheral vascular status of a hypertensive patient.     

甲状腺肿物的临床、病理及超微病理的诊断分析

目的 通过分析甲状腺外科手术术患者的临床与病理又超微病理检查结果，了解甲状腺疾病的电镜诊断价值。方法 回顾2年中甲状腺肿物手术切除术患者80例，常规病理学检查以及电镜诊断的结果。根据滤泡上皮超微结构判断肿物病理性质。结果 临床诊断与病理诊断符合率低。光、电镜的病理诊断相符者78例；不相符者2例，光镜诊为甲状腺腺瘤，电镜诊为甲状腺癌。结论 甲状腺疾病的电镜检查，可了解滤泡上皮在不同疾病时的病变，修正病理学诊断的 错误，对于疾病的确诊具有重要的价值。     

腹腔镜与开腹脾切断流术的临床对比研究

目的比较腹腔镜脾脏切除术（LS）加贲门周围血管离断术（ED）同开腹脾脏切除术（OS）加贲rJ周围血管离断术对于治疗伴有难治性静脉曲张破裂出血的门脉高压症患者的疗效及安全性。方法回顾性分析2002年1月至2012年7月期间内,77例行OSED术以及同期67例行LSED术治疗的门脉高压症患者的临床资料及并发症情况。结果LSED组的手术时间和OSED组之间无明显差别（P=0．757）。LSED组术中出血,术后胃肠功能恢复时间明显少于OSED组（P〈0．001,P=0．019）。术后LSED组ALT、AST以及TBIL三项指标明显低于OSED组（P=0．002,P=0．002,P=0．015）。术后PLT、WBC以及H11检查结果两组之间无叫显差别（P=0．786,P=0．056,P=0．973）。术后并发症LSED组门静脉系统血栓发生率高十OSED组（P=0．037）,其余并发症两组之间无显著差异。结论LSED术在治疗伴有难治性食管胃底静脉曲张出血的门脉高压症时具有安全、有效以及创伤小的特点。     

Intermittent pneumatic compression enhances neurovascular ingrowth and tissue proliferation during connective tissue healing: a study in the rat.

Intermittent pneumatic compression (IPC) is a treatment method to decrease venous stasis and stimulate blood flow. Recently, it was hypothesized that IPC may exert positive effects on tissue healing, a process highly dependent upon adequate circulation. In this study, we investigated the effects of daily 1-h IPC treatment during 2 and 4 weeks post-rat Achilles tendon rupture. The tendons were subjectively and semiquantitatively analyzed for collagen organization, fibroblast density, angiogenesis, and the occurrence of sensory neuropeptides, substance P (SP) and calcitonine gene related peptide (CGRP), as well as for a nerve regeneration marker, growth associated protein 43 (GAP-43). After 2 weeks of treatment, fibroblast density increased by 53% (p = 0.0004), vessel density by 64% (p = 0.022), and the occurrence of SP by 110% (p = 0.047) and CGRP by 47% (p = 0.0163) compared to untreated controls. Following 4 weeks of treatment, both the occurrence of sensory neuropeptides and the vessel density remained significantly higher (p < 0.05), whereas fibroblast density returned to normal. However, at 4 weeks the treated tendons displayed a higher degree of organized parallel collagen fibers, a sign of increased maturation. Daily IPC treatment improves neurovascular ingrowth and fibroblast proliferation in the healing tendon and may accelerate the repair process.     

Aortic xenograft valve performance at eight years. A comparative study

The medium-term performance of commercially available xenograft prostheses in the aortic position, was evaluated in 198 patients operated upon since 1975. No associated procedures were performed in these patients in whom a variety of prostheses was employed. The valve behaviour has been compared with other xenograft series, homografts and synthetic prostheses. There was a 5.5% hospital death rate and a 7.5% late mortality. Five late deaths were valve related, five were unrelated to the valve and four were of unknown cause but in elderly patients. At eight years, 86.1% of patients were alive, the majority functionally improved. Thromboembolic events were considerably fewer than those experienced with most non-biological prostheses, all but three events being transient. Re-operation for primary valve dysfunction was a safe procedure but re-operation for infected prostheses carried a high mortality. In comparing the aortic xenograft with other prostheses, severe dysfunction was found to occur with similar frequency in all prostheses up to eight years and was rare. Mild prosthetic dysfunction (asymptomatic diastolic murmur) occurs in about 25% of all tissue valves at eight years, including the homograft. The progression, or otherwise, of mild dysfunction has yet to be evaluated in currently available xenograft prostheses.     

Activation of the rostral ventrolateral medulla in an acute anesthetized rodent strychnine model of allodynia.

After the administration of intrathecal strychnine, allodynia is manifested as activation of supraspinal sites involved in pain processing and enhancement of cardiovascular responses evoked by normally innocuous stimuli. The objective of this study was to investigate the effect of strychnine-induced allodynia on adrenergic neuronal activity in the C1 area of the rostral ventrolateral medulla (RVLM), a major site involved in cardiovascular regulation. The effect of intrathecal strychnine (40 microg) or saline followed by repeated hair deflection to caudal lumbar dermatomes in the urethane-anesthetized rat was assessed by measuring voltammetric changes in the RVLM catechol oxidation current (CA x OC), mean arterial pressure (MAP), and heart rate (HR). After the administration of intrathecal strychnine, hair deflection evoked a significant and sustained increase in the RVLM CA x OC and MAP (peak 146.4%+/-5.6% and 159%+/-18.4% of baseline, respectively; P < 0.05). There was a nonsignificant increase in HR (peak 128%+/-8.2%). In the absence of hair deflection, there was no demonstrable change. Intrathecal saline-treated rats failed to demonstrate changes in RVLM CA x OC, MAP, or HR. In the present study, we demonstrated that, after the administration of intrathecal strychnine, innocuous hair deflection evokes temporally related neuronal activation in the rat RVLM and an increase in MAP. This suggests that the RVLM mediates, at least in part, the cardiovascular responses during strychnine allodynia. IMPLICATIONS: Neural injury-associated pain, as manifested by allodynia, is resistant to conventional treatment. In a rat model of allodynia, we demonstrated activation of the brain region involved in sympathetic control. Innovative therapies that target this region may be successful in managing this debilitating condition.     

Popliteal entrapment as a result of neurovascular compression by the soleus and plantaris muscles.

Intermittent claudication may occur in well-conditioned athletes because of an unusual form of popliteal artery entrapment that results from overtraining. These patients complain of calf muscle cramping, rapid limb fatigue, and occasional paresthesias on the plantar surface of the foot when running on inclines or when repetitive jumping is performed. Results of plethysmographic screening tests for popliteal entrapment are positive in these patients. Magnetic resonance angiography and intravenous digital subtraction angiography studies, however, do not demonstrate findings typical of anatomic popliteal entrapment. No evidence exists of aberrant positioning of the popliteal artery in foot neutral positioning, but with forced plantar flexion, the neurovascular bundle is deviated and compressed laterally. Surgical exploration of the popliteal fossa demonstrates no obvious musculotendinous abnormality. Symptoms of claudication and arterial compression are relieved by surgical release of the soleus muscle from its tibial attachments, resection of its fascial band, and resection of the plantaris muscle.     

Hemifacial spasm: ultrastructural changes in the facial nerve induced by neurovascular compression.

In patients with hemifacial spasm, pathological changes were found in the facial nerve resulting from neurovascular compression-distortion. These changes are simular to those noted in trigeminal neuralgia.     

Spasmodic torticollis due to neurovascular compression of the 11th nerve. Case report

An unusual case of spasmodic torticollis caused by posteroinferior cerebellar artery compression of the spinal accessory nerve is reported. The spasmodic torticollis was cured by abolishing the neurovascular compression.     

Arterial cross compression of the trigeminal nerve at the pons in trigeminal neuralgia. Case report with autopsy findings.

The autopsy findings in a patient with trigeminal neuralgia who died from unrelated causes are presented. Arterial cross compression of the appropriate trigeminal nerve at the pons was demonstrated. The relationship of arterial cross compression to trigeminal neuralgia is briefly discussed.