A 65-year-old man had progressive vertebrobasilar insufficiency, including cerebellar infarction, despite aggressive use of antiplatelet agents (aspirin, dipyridamole) and anticoagulants (heparin, Coumadin). Angiography showed 99% stenosis at the origin of the right vertebral artery and 99% stenosis of the basilar artery proximal to both superior cerebellar arteries. Because the patient 's sign...

Compromise of blood flow in the vertebral arteries associated with head rotation is generally considered an uncommon cause of vertebrobasilar insufficiency. It can occur at virtually any level of the cervical spine. We present two cases of transient total occlusion of the left vertebral artery at the atlantoaxial joint during head rotation to the right. In one case, the contralateral vertebral ...

Subclavian steal syndrome, which comprises reversal of flow in the ipsilateral vertebral artery with stenosis or occlusion of the subclavian artery (SA) or brachiocephalic trunk (BCT), was first described by Contorni in 1960 [1]. This clinical syndrome manifests with the signs and symptoms of vertebrobasilar insufficiency, but can also be asymptomatic. This paper describes a step-by-step techni...

Cervical vertigo has long been a controversial entity and its very existence as a medical entity has advocates and opponents. Supporters of cervical vertigo claim that its actual prevalence is underestimated due to the overestimation of other diagnostic categories in clinics. Furthermore, different pathophysiological mechanisms have been attributed to cervical vertigo. Here the authors discuss ...

The function of the accommodation system is to provide a clear retinal image of objects in the visual scene. The system was previously thought to be under simple continuous (i.e., single mode of operation) feedback control, but recent research has shown that it is under discontinuous (i.e., two stimulus-dependent modes of operation) feedback control by means of fast and slow processes. A model ...

概要 1959年 より1963年 の5年 間 に,東 邦大学阿都 内科 で観察 した内頚 お よび椎 骨脳 底 動脈循環不 金 症45例 にっ き,臨 床症状の特 徴を統 計的 に観察す るとともに,そ の発生頻 度を検討 した.ま た,本 症 と本 態性 高血圧症,低 血圧症,正 常血圧 者お よび若年性起 立性 低血圧 の 患者群につ いて比較 し,本 症 の発生機序 につ い て検討 を加 えた.そ の結果,本 症 の大多数は既 往に高血圧 を有 し,発 作時 に血 圧 低 下をし たが,約70%は 起立性低 血圧 を伴なつ た高血圧症 であつ た.Mecholyl試 験 で は 変感神 経 緊 張低下 を示 す点で他群 と異なつ てお り,体 位変換 に よつて血 中norepinephrineが 増加 せず,安 静時 の 血中norepinephrineは 本態性高血圧症 ...

Three areas of substantial evolution are covered in this review: the use of bioimplantable materials in glottic insufficiency, improvement in therapeutic strategies for laryngeal papillomatosis and surgical organ/functionpreservation treatment of laryngeal malignancy. Overall, the discipline of laryngology continues to evolve and will become increasingly important with exciting technological ad...

Convergence insufficiency is a common binocular vision disorder affecting approximately 5% of the population in the United States. It is often associated with a host of symptoms that occur when doing near work, such as reading and computer viewing. This article reviews the existing literature on convergence insufficiency including etiology, diagnosis, sensorimotor findings, and management.