The surgical management of brain abcess / by Alfred W. Adson and Winchell McK. Craig.

  • Adson, Alfred W. (Alfred Washington), 1887-1951.
Date:
1935?]
Catalogue details

Licence: In copyright

Credit: The surgical management of brain abcess / by Alfred W. Adson and Winchell McK. Craig. Source: Wellcome Collection.

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    invasion of the cranial cavity by the infecting organism into two major groups, the more common including foci in contiguous structures. This group in¬ cluded infections following injuries to the skull, in a great many cases result¬ ing from osteomyelitis developing from purulent infection in the mucous membrane lining the cavities in the temporal bones or in the accessory nasal sinuses. The second group of important etiological factors he designated as infections of the brain through the blood-stream from some distant site of suppuration, resulting in metastatic or haematogenous brain abscess. In this classification were included osteomyelitis of the long bones, bronchiectasis, pulmonary abscess and empyema, and, in rare instances, pericarditis, infective endocarditis, and so forth. Table I Evans' Classification of Methods of Invasion A. Direct extension 1. Otitis media and mastoiditis. 109 a. Purulent thrombosis of the lateral sinus. 37 b. Osteomyelitis of tympanic wall. 28 c. Spread via internal auditory meatus. 1 d. Spread along the adventitial spaces of perforating blood-vessels. . 43 2. Suppuration in the nasal cavity and accessory sinuses. 12 a. Osteomyelitis of the sinus wall. 7 b. Spread along perineural spaces. 3 c. Spread along veins. 2 3. Following trauma to skull. 8 4. Invasion of the brain by malignant growths. 2 B. I hematogenous spread 1. Metastatic brain abscess resulting from intrathoracic suppuration. . 22 a. Chronic bronchiectasis. 17 b. Empyema. 3 2. Metastatic brain abscess resulting from extrathoracic suppuration . 24 C. Method of spread doubtful. 2 D. Source, and therefore method, of spread doubtful or unknown. 15 Total. 194 Evans,17 in a study of 194 cases of brain abscess at necropsy, discussed the etiology under headings depending on whether infection was transmitted to the brain from an adjacent or distant primary focus (Table 1). Suppurative otitis media is the infection which most frequently leads to intracranial complications, and this results from direct extension of the in¬ fective process. Evans stated that 83.2 per cent, of all brain abscesses in his series were the result of direct extension from the middle ear and antrum. Macewen discovered that an abscess may occur independent of a visible tract of inflammation, the organism being conveyed by direct vascular connections. 1 his is either due to an infective thrombosis spreading through the veins into the pia mater or brain or to a reversal of the blood-stream with carry¬ ing of portions of the infected thrombus inward. Although chronic otitis media pievails as a causative factor, acute otitis may lead to brain abscess when the infection is a virulent one.