Alfred J. Luessenhop

Computerized Transaxial X-ray Tomography of the Human Body

The ACTA-Scanner has virtually unlimited potential in the evalution of any part of the body. The usefulness of the technique has already been shown in the appraisal of pathologies of the brain and cerebrospinal fluid cavities. The orbits and the eyeballs, the facial sinuses, and skull base lesions have also been elucidated. Tumors of the larynx, pharynx, thyroid, and parathyroid; lymphomas; and pathology of the spine and spinal cord are well within the reach of this new diagnostic methodology. Lung pathologies, such as emphysema, pneumonias, neoplasms, infarctions, pleural effusions and granulomatous diseases, and mediastinal pathology represent a challenging complex of lesions to be appraised by ACTA-scanning. For the heart, there is great potential for observing cardiac chamber size, hypertrophy of ventricular or atrial walls, and ventricular or aortic aneurysms, and possibly for recognizing the damaged myocardial tissue immediately after or some time after an infarction. The abdominal pathologies that can be studied are almost uncountable: gastric neoplasms, pancreatic cysts and stones, gallstones, neoplasms of the liver and pancreas, bowel tumors, abdominal aortic aneurysms, renal neoplasms and cysts, atrophy of the kidneys, bladder tumors, uterine tumors, ovarian cysts, and many more. Although bones and joints are adequately demonstrated by conventional x-ray techniques, there is no doubt that as the new technique is developed ACTA-grams will contribute significant information in the transverse plane, as well as in densitometric analyses. The impact of ACTA-scanning will not be limited to the diagnostic area, but will extend, at least indirectly, to general patient management and to some aspects of medical economics as well. Risk-laden, technically complex, and costly diagnostic procedures, sometimes requiring lengthy hospitalization, will in some cases be eliminated. The simple, innocuous, and noninvasive ACTA-scanning can be performed on an outpatient basis. Repeated follow-up examinations should be easily accepted by the patients, considering that this diagnostic test is carried out without discomfort. The entire field of diagnostic radiology is on the verge of revolutionary changes.

Anatomical Grading of Supratentorial Arteriovenous Malformations for Determining Operability

After the study of over 300 angiograms of supratentorial cerebral arteriovenous malformations (AVMs), the authors have formulated an anatomical grading scheme of I to IV to correspond to the degrees of surgical difficulty for total obliteration. The grading is based upon the number of directly participating arteries for which there is a standardized nomenclature. Occasionally, allowance for clinical grading, in addition to this anatomical grading, must be made. Also, for the anticipation of morbidity, but not mortality, the location of the lesion is important. The authors present the postoperative results in a series of 49 patients to demonstrate the clinical usefulness of the grading scheme.

Positional vertigo and the cerebellar vermis

A patient with lower and posterior vermis hematoma presented with truncal ataxia; paroxysmal, positional, downbeating nystagmus; and saccade dysmetria. Drainage of the hematoma resulted in complete resolution of all signs and symptoms.

Estimate of the Incidence and Importance of Circulatory Breakthrough in the Surgery of Cerebral Arteriovenous Malformations

Severe hemorrhagic brain swelling has been described occasionally in patients with cerebral AVMs after surgical interruption for feeding arteries, surgical excision, and embolization. The proposed mechanism is an abrupt increase in perfusion pressure in the vasculature of the normal adjacent brain which has lost its capacity to autoregulate. The term circulatory breakthrough has been adopted to describe this. The authors found its incidence to be 3 in 66 patients in a surgical series, but lesser degrees of circulatory breakthrough in smaller lesions may have accounted for most of mortality and morbidity that was encountered. Its importance in embolization is less certain because of the possibility of infarction. It is proposed that better control of this problem by presurgical embolization, surgical staging, and graduated degrees of induced hypotension postsurgery may be necessary if the larger cerebral AVMs are to be excised with mortality and morbidity less than the natural history.

Childhood Medulloblastoma Presenting with Hemorrhage

Cerebellar hemorrhage is rare in childhood, and is usually the result of trauma or a ruptured arteriovenous malformation. We report acute subarachnoid hemorrhage as the presenting manifestation of medulloblastoma and review the atypical presentation and causes of cerebellar hemorrhage in infants and children.

Surgical Treatment for Deep-Seated or Large AVMs

Excluding patients with primarily durai or intraorbital arteriovenous malformations (AVMs), our experience over the past 25 years includes approximately 480 patients with AVMs, primarily in the brain. The size distribution of these is approximately as follows: 50% were 3 cm or less, 20% were 4 cm, 15% were 5 cm, 10% were 6 cm, and 5% were greater than 6 cm. This distribution is probably tilted toward larger AVMs because many of our patients were referred when their lesions was considered not amenable to surgical excision.