In 1918, the American neurosurgeon Walter Dandy (1886–1946) first described the injection of air into the cerebral ventricles as an aid to clinical diagnostics (Dandy, 1918). By revealing alterations in the shape, size or position of the ventricles on the radiogram, ventriculography provided a valuable tool to indirectly predict the presence and localization of brain tumours. The following year, Dandy introduced a method for the ‘intraspinous’ injection of air, pneumoencephalography, which allowed for the radiological visualization of tumour-induced changes of both the ventricular system and the cerebral subarachnoid space (Dandy, 1919). With the invention of ventriculography and pneumoencephalography—jointly referred to as cerebral pneumography—Dandy laid the groundwork for subsequent methods to directly or indirectly visualize lesions of the CNS with radiopaque substances, including contrast myelography, arterial encephalography and isotope encephalography (Moniz, 1927; Moore, 1948). The value of cerebral pneumography was, however, not undisputed, as the technique was not devoid of danger and often challenging to interpret. Hence, there was a feeling that to depend on radiography was to renounce oneself as a neurologist, by exposing patients to dangerous procedures, while thorough clinical examination performed by a skilful neurologist, would, in many cases, be sufficient for the diagnosis and localization of brain tumours. In this article, we wish to celebrate the centenary of Walter Dandy’s inventions of ventriculography and pneumoencephalography, procedures that, despite their dangers and shortcomings, significantly contributed to the diagnosis and localization of brain tumours during the 20th century.

中文翻译：

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脑呼吸图和20世纪脑肿瘤的定位

1918年，美国神经外科医生Walter Dandy（1886年至1946年）首次描述了将空气注入脑室作为临床诊断的辅助手段（Dandy，1918年）。通过在放射线照片上揭示脑室的形状，大小或位置的变化，脑室造影术提供了一种有价值的工具，可以间接预测脑肿瘤的存在和定位。次年，Dandy提出了一种“脑内”注射空气的方法，即脑电图技术，该方法可以对肿瘤引起的心室系统和脑蛛网膜下腔的变化进行放射学可视化（Dandy，1919年）。随着脑室造影和肺脑波造影技术的发明（统称为脑部肺动脉造影），Dandy为后续方法进行了直接或间接可视化不透射线物质对CNS病变的研究奠定了基础，包括造影剂脊髓造影，动脉脑造影和同位素脑造影（Moniz，1927年； Moore） ，1948年）。然而，由于该技术并非没有危险，而且常常难以解释，因此，肺气描记术的价值也不容置疑。因此，有一种感觉，依靠放射线照相术可以使患者接受危险的手术，从而放弃自己作为神经科医师的资格，而在许多情况下，由熟练的神经科医师进行的全面临床检查将足以对放射科进行诊断和定位。脑肿瘤。在本文中，