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  • Author or Editor: Michael G. J. O’Sullivan x
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Lena Mary Houlihan, Evgenii Belykh, Xiaochun Zhao, Michael G. J. O’Sullivan, and Mark C. Preul

Transorbital surgery has gained recent notoriety because of its incorporation into endoscopic skull base surgery. The use of this surgical corridor has been pervasive throughout the 20th century. It has been utilized by multiple disciplines for both clinical and experimental purposes, although its historical origin is medically and ethically controversial. Hermann Knapp first introduced the orbital surgical technique in 1874, and Rudolf Krönlein introduced his procedure in 1889. Rivalry between Walter Dandy in neurosurgery and Raynold Berke in ophthalmology further influenced methods of tackling intracranial and intraorbital pathologies. In 1946, Walter Freeman revolutionized psychosurgery by completing seemingly successful transorbital leucotomies and promoting their minimally invasive and benign surgical characteristics. However, as Freeman’s legacy came into disrepute, so did the transorbital brain access corridor, again resulting in its stunted evolution. Microsurgery and endoscopy further influenced the use, or lack thereof, of the transorbital corridor in neurosurgical approaches. Historical analysis of present goals in modern skull base surgery echoes the principles established through an approach described almost 150 years ago: minimal invasion, minimal morbidity, and priority of patient satisfaction. The progression of the transorbital approach not only reflects psychosocial influences on medical therapy, as well as the competition of surgical pioneers for supremacy, but also describes the diversification of skull base techniques, the impact of microsurgical mastery on circumferential neurosurgical corridors, the influence of technology on modernizing skull base surgery, and the advancing trend of multidisciplinary surgical excellence.

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Kristian Aquilina, Christopher Lim, Mahmoud Hamdy Kamel, Charles J. Marks, Michael G. O'Sullivan, and Catherine Keohane

✓ Epithelioid hemangioendothelioma (EH) is a rare tumor of vascular origin. The authors describe two cases of spinal EH, one involving the T-10 vertebra and the second involving the upper cervical spine. In the first case the patient underwent resection of the tumor; this case represents the longest reported follow-up period for spinal EH. In the second case, extensive involvement of C-2, C-3, and C-4 as well as encasement of both vertebral arteries precluded safe tumor resection, and posterior occipitocervical stabilization was performed. The patient subsequently died of metastatic disease. The findings in these two cases underscore the difficulty in predicting the clinical behavior of spinal EH based solely on histological and clinical features as well as the uncertainty of the roles of surgery, chemotherapy, and radiotherapy in the oncological management of a spinal tumor for which clinical data are very limited.

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Michael G. O'Sullivan, Patrick F. Statham, Patricia A. Jones, J. Douglas Miller, N. Mark Dearden, Ian R. Piper, Shirley I. Anderson, Alma Housley, Peter J. Andrews, Susan Midgley, Jane Corrie, Janice I. Tocher, and Robin Sellar

✓ Previous studies have suggested that only a small proportion (< 15%) of comatose head-injured patients whose initial computerized tomography (CT) scan was normal or did not show a mass lesion, midline shift, or abnormal basal cisterns develop intracranial hypertension. The aim of the present study was to re-examine this finding against a background of more intensive monitoring and data acquisition.

Eight severely head-injured patients with a Glasgow Coma Scale score of 8 or less, whose admission CT scan did not show a mass lesion, midline shift, or effaced basal cisterns, underwent minute-to-minute recordings of arterial blood pressure, intracranial pressure (ICP), and cerebral perfusion pressure (CPP) derived from blood pressure minus ICP. Intracranial hypertension (ICP ≥ 20 mm Hg lasting longer than 5 minutes) was recorded in seven of the eight patients; in five cases the rise was pronounced in terms of both magnitude (ICP ≥ 30 mm Hg) and duration. Reduced CPP (≤ 60 mm Hg lasting longer than 5 minutes) was recorded in five patients.

Severely head-injured (comatose) patients whose initial CT scan is normal or does not show a mass lesion, midline shift, or abnormal cisterns nevertheless remain at substantial risk of developing significant secondary cerebral insults due to elevated ICP and reduced CPP. The authors recommend continuous ICP and blood pressure monitoring with derivation of CPP in all comatose head-injured patients.