Delayed visual loss due to trauma of the internal carotid artery

The group of six patients in this study experienced delayed visual loss following head trauma. Visual loss occurred from 1 day to 13 years after the initial injury. All patients suffered indirect trauma to the internal carotid artery resulting in formation of either an aneurysm or pseudoaneurysm or a carotid-cavernous fistula. Review of the radiologic and clinical findings was performed in six patients. The diagnosis was established by computed tomography, magnetic resonance imaging, and angiography. All patients had follow-up clinical evaluation and imaging studies. Treatment by neurosurgical or interventional neuroradiologic procedures resulted in significant visual improvement in five patients. Different pathophysiologic mechanisms could be correlated with the delayed visual loss produced by the two types of lesions. The pathologic changes associated with the aneurysms/pseudoaneurysms included direct compression of optic nerves and/or chiasm and intracranial hematoma. A carotid-cavernous fistula caused delayed visual loss by either hematoma at the orbital apex or compression of the chiasm and/or optic nerves by saccular dilatation of the cavernous sinus. The delayed onset of decreased vision following head trauma should alert the physician to the possibility of a traumatic aneurysm/pseudoaneurysm or a carotid-cavernous fistula. Different neuro-ophthalmologic symptoms can usually be correlated with the pathologic changes demonstrated by neuroimaging procedures.     

ABX-CBL (Abgenix Inc)

Abgenix has acquired rights to ABX-CBL, an antibody in phase II trials for the potential treatment of graft versus host disease (GvHD). The antibody, previously known as CBL-1 was discovered by the CV Cancer Center. Abgenix planned to continue phase II trials in GvHD in 1998 after completing a confirmatory clinical study required by a manufacturing process change. ABX-CBL will also be evaluated in kidney and other organ transplant rejection indications. In January 1998, Abgenix announced that it had commenced a phase II trial of the antibody at eight clinical centers to confirm the results of previous phase II trials. The study will involve 48 patients. Results of the trial were expected by the third quarter of 1998. However, by December 1998 they had not been reported. ABX-CBL could also potentially be used to treat inflammation and autoimmune diseases such as rheumatoid arthritis and psoriasis. In a clinical trial, ABX-CBL was administered to ten patients with acute steroid-resistant GvHD. The overall response rate was 90%, with GvHD completely resolved in five patients and improved by at least two grades in four others. The antibody was well-tolerated and did not exacerbate post-transplant immunodeficiency. In another study involving 43 patients who developed GvHD after kidney transplant, ABX-CBL was effective in reversing the first rejection and preventing recurrence of rejection. It was shown to be well tolerated with no serious adverse events reported.     

Ophthalmodynamometry: a reappraisal

The accuracy of ophthalmodynamometry (ODM) was retrospectively analyzed in 36 patients who had ophthalmic examinations prior to carotid arteriography. In 75% of those patients, ODM correctly predicted the presence of absence of significant stenosis (ie, 50% or greater) or occlusion of the internal carotid artery. A 30% false-negative rate and 19% false-positive rate was found in this study. The accuracy was not improved when the examiner had more experience with the test. The accuracy of ODM with staff members who regularly perform the examination was 68% as compared to the ophthalmology residents' accuracy of 76%. Causes of false-negative and positive results include subjectivity of the examination, stenosis of arteries other than the internal carotids, and development of collateral circulation as was demonstrated arteriographically in 2 of our patients.     

Endothelium: The Next Frontier in Biocompatibility

Abstract: Vascular endothelium plays a central role in two specific functional systems. It controls vascular tone, hemostasis, and substance transport. The endothelium is the “docking station” for trapping, deactivation, and re-generation of activated blood compounds and provides the principal clearance mechanism for biologically active mediators released by different cell types. The second function is a regenerational one. During the period between insults (or between dialysis sessions), the endothelium has to restore the “first line of defense,” that is, to regenerate the injured athrombogenic surface of the vessel wall and its antioxidative potential, defoliate damaged endothelial cells, and interpolated new ones. These two important endothelial activities are required over and above its basic functions. Future research in artificial organs must take into account that continuous or intermittent blood-membrane contact creates an altered endothelial response. These altered responses may result in adaptional reactions that may differ substantially in the acutely ill patient on continuous venovenous hemofiltration (CVVH) or in a stable patient on maintenance hemodialysis. By a reduction in such factors as immediate or delayed cell-cell interactions (direct or indirect), it may be possible to influence the long-term outcome of chronic hemodialysis patients. Other research should strive to enhance those factors of endothelial function that are essential in the defensive and restorative properties of endothelial tissue. This is especially important in such continuous therapies as CVVH, long-term membrane oxygenation, and artificial heart and blood vessels. Currently, there are more unanswered questions than possible answers concerning endothelial functions in long-term hemodialysis patients, but it is clear that excluding endothelial cell behavior from investigation of extracorporeal therapy in the future would be a substantial omission.     

Ocular and cerebral involvement in familial lymphohistiocytosis.

A 5-month-old infant girl died of familial lymphohistiocytosis. The central nervous system showed widespread perivascular infiltration of the cerebral pia and arachnoid, the cerebral white matter and deep gray matter, the cerebellum, and brain stem by lymphocytes, benign appearing histiocytes, and macrophages with erythro-and lymphophagocytosis. The eyes had mild infiltration of the anterior uveal tract, moderate involvement of the inner retina, and marked infiltration of the optic nerves by identical cells.     

Traumatic injuries

Eye injury caused by foreign materials may be inconsequential or severe. The primary physician must rapidly assess the nature and extent of injury in relation to the causative agent to determine whether general office treatment will suffice or if the patient must be referred to an ophthalmologist.