Problems of Chorioretinal Biopsy 1
Problems of Chorioretinal Biopsy 1
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脉络膜视网膜活检的问题1
DOI：
10.1177/014107688007300604
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发表时间：
1980
影响因子：
17.3
通讯作者：
I. Constable
中科院分区：
文献类型：
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作者：
I. Constable
毫无疑问，视网膜和脉络膜无法进行手术活检，阻碍了对各种病理状况的了解。弥漫性遗传性脉络膜视网膜营养不良、脉络膜炎、视网膜的各种炎性疾病，甚至血管或退行性疾病如糖尿病性视网膜病变，几乎没有通过现代实验室技术进行分析。现在可用于研究正常和病变组织中细胞化学和动力学的技术已经集中到微观水平。甚至不太复杂的技术，如免疫荧光抗体标记，可用于肾脏，肝脏和皮肤病的研究多年，尚未用于脉络膜视网膜疾病的理解和管理。在临床层面，识别视网膜和脉络膜感染，如单纯疱疹和真菌，虽然罕见，但有时可能是至关重要的，因为越来越有效的药物正在变得可用。一种安全、实用的脉络膜视网膜活检技术也将大大扩展人类疾病动物模型的研究。维持大量具有自然或诱发的脉络膜视网膜疾病的高等动物是极其昂贵的。对同一只眼睛进行连续活检将减少疾病进展中个体差异的问题。在目前视网膜和脉络膜组织取样的障碍之下，似乎蕴藏着大量的信息。由于脉络膜出血、玻璃体脱落和视网膜脱离的风险，脉络膜视网膜活检长期以来被认为是不切实际的。Peyman等人（1975 a，B，c）描述了一种全层眼壁活检方法，该方法依赖于重度透热疗法应用以防止出血和广泛的玻璃体切除术以管理玻璃体损失。由于这种方法相当于一个主要和复杂的外科手术，它还没有得到广泛的接受。Griffin等人（1975）报告了经玻璃体活检技术，但尚未报告在动物或人类中的进一步发展。我们推断，采用后一种方法很难控制出血，而且标本会被仪器损坏。因此，我们决定在正常犬中检查直接经巩膜方法（Constable等，1980）。在全身麻醉下对40只狗进行脉络膜视网膜活检。侧眶切开术后，暴露巩膜，并在颞侧涡静脉后方选择活检部位。直径约3 mm的巩膜全层切口暴露下方脉络膜。在早期实验中，用20%甘露醇（2 g/kg）软化眼睛。然后用细剪刀三次切割切除脉络膜和视网膜块。在这些情况下，玻璃体通常但不总是丢失，脉络膜出血量大但时间短。因此，认识到如果要避免这些并发症，需要更精确地控制条件，此后使用经股动脉插管监测全身血压。在即将切除活检组织之前，通过透照选择活检部位以避开主要脉络膜血管，将全身血压降低至平均50 mmHg。这是用吸入麻醉气体中的4%氟烷实现的。此外，脉络膜血管收缩受到控制性过度通气的促进，这将动脉氧分压升高至约200 mmHg，并将二氧化碳降低至15 mmHg。局部药理学血管收缩剂，包括肾上腺素，苯肾上腺素和鸟加压素（POR-8）似乎没有用，被放弃。在控制性全身低血压、高氧合和
There can be no doubt that the inaccessibility of the retina and choroid to surgical biopsy has retarded the understanding of a variety of pathological conditions. The diffuse, hereditary chorioretinal dystrophies, choroiditis, various inflammatory diseases of the retina, and even vascular or degenerative conditions such as diabetic retinopathy, have been subjected to little analysis by modern laboratory techniques. The technology now available to study cellular chemistry and dynamics in normal and diseased tissues has been focused down to microscopic levels. Even less sophisticated techniques such as immunofluorescent antibody labelling, available for years in the study of renal, hepatic, and dermatological diseases, have not been used in the understanding and management of chorioretinal disease. At the clinical level, identification of infections of the retina and choroid such as herpes simplex and fungi, although rare, might sometimes be crucial now that increasingly effective drugs are becoming available. A safe, practical chorioretinal biopsy technique would also greatly expand the study of animal models of human disease. The maintenance of large numbers of higher order animals with natural or induced chorioretinal disease is prohibitively expensive. Sequential biopsy on the same eyes would reduce the problems of individual variation in progression of disease. It seems possible that a treasure of information simmers beneath the present barrier to tissue sampling of the retina and choroid. Chorioretinal biopsy has long been considered impractical because of the risks of choroidal bleeding, vitreous loss and retinal detachment. Peyman et al. (1975a, b, c) described a fullthickness eye wall biopsy method which relied on heavy diathermy applications to prevent bleeding and extensive vitrectomy to manage vitreous loss. Since this method amounted to a major and complicated surgical procedure, it has not found widespread acceptance. A transvitreal biopsy technique was reported by Griffin et al. (1975),but further development in animals or humans has not been reported. We reasoned that with this latter method control of haemorrhage would be difficult and the specimen damaged by the instruments. We therefore decided to examine the direct trans-scleral method in normal dogs (Constable et al. 1980). Forty dogs were subjected to chorioretinal biopsy under general anaesthesia. After lateral orbitotomy the sclera was exposed and a biopsy site selected on the temporal side posterior to the vortex veins. A scleral full-thickness incision of about 3 mm diameter exposed the underlying choroid. In early experiments the eye was softened with mannitol 20%(2 g/kg), A block of choroid and retina was then excised with three cuts from fine scissors. Vitreous was usually but not always lost and profuse but brief choroidal bleeding occurred under these conditions. It was thus realized that conditions would need to be much more precisely controlled if these complications were to be avoided, and thereafter a transfemoral aortic cannula was used to monitor systemic blood pressure. Immediately prior to excision of the biopsy, the site of which was selected by transillumination to avoid major choroidal vessels, the systemic blood pressure was reduced to a mean of 50 mmHg. This was achieved with 4% halothane in the inspired anaesthetic gases. In addition, choroidal vasoconstriction was encouraged by controlled hyperventilation, which raised arterial oxygen tension to about 200 mmHg and reduced carbon dioxide to 15 mmHg. Topical pharmacological vasoconstrictors including adrenalin, phenylephrine and ornipressin (POR-8) did not seem useful and were abandoned. Under conditions of controlled systemic hypotension, hyperoxygenation and