1/3. Broadening the clinical spectrum: unusual presentation of spontaneous cerebrospinal fluid hypovolemia. Case report.The syndrome of spontaneous intracranial hypotension is characterized by orthostatic headaches in conjunction with reduced cerebrospinal fluid (CSF) pressure or CSF volume, and characteristic magnetic resonance (MR) imaging findings. A 50-year-old man presented with a 1-year history of paroxysmal ataxia of gait and short attacks of blurred vision when he stood up from a recumbent position and began to walk. Orthostatic headache was not a feature of his clinical presentation. Magnetic resonance images of the brain revealed diffuse enhancement of the dura mater and hygromas over both cerebral convexities. Magnetic resonance images of the spine demonstrated dilated cervical epidural veins and dilation of the perimedullary veins. Radionuclide cisternography identified a CSF leakage that was localized to the T12-L1 level on subsequent myelograms and on computerized tomography scans obtained after the myelograms. An epidural blood patch was administered and visualized with tungsten powder. The patient's clinical symptoms and sites of disease on imaging completely resolved. The unusual clinical presentation in this case--paroxysmal ataxia of gait, lack of orthostatic headaches, and dilated epidural and perimedullary venous plexus--supports a recently noted broadening of both the clinical and imaging characteristics of spontaneous intracranial hypovolemia.- - - - - - - - - - ranking = 1keywords = intracranial hypotension, hypotension (Clic here for more details about this article) |
2/3. Hypovolemic ischemic optic neuropathy.BACKGROUND: Ischemic optic neuropathy refers to an acute event of ischemia, or decreased blood flow, to the optic nerve resulting in varying degrees of vision loss and visual field defects. Typically this disease affects the elderly population who experience systemic diseases that compromise the blood flow efficiency of the optic nerve head (e.g., giant-cell arteritis, hypertension, diabetes, etc.). However, cases of blood loss to the optic nerve, secondary to traumatic injuries or surgeries, have also been shown to result in ischemic optic neuropathy, regardless of age. It seems that in these cases, the resulting anemia and hypotension play contributing roles in the development of ischemic optic neuropathy. methods: A 41-year-old black man came to us with optic nerve head pallor O.S., count-fingers vision O.S., positive afferent pupillary defect O.S., and a central scotoma O.S. after being hospitalized and treated for a stab wound to his left neck that severed his left carotid artery at the bifurcation. RESULTS: This patient had been seen in the optometry Clinic two years before the stab-wound incident. At that time, he had 20/20 vision in his left eye and no remarkable neurological deficits. His ocular presentation after the traumatic hypovolemic event was probably a direct result of the hypoperfusion to the left optic nerve head. This patient was diagnosed with a hypovolemic, or blood loss-related, ischemic optic neuropathy (O.S.). CONCLUSIONS: patients who experience large amounts of blood loss due to trauma, surgery, internal bleeding, etc. and report vision loss should be screened for possible optic nerve ischemia. As eye care providers, when we are presented with patients who have optic nerve head atrophy, we should inquire about events that may have precipitated blood loss, potentially triggering ischemic optic neuropathy.- - - - - - - - - - ranking = 0.024201144030387keywords = hypotension (Clic here for more details about this article) |
3/3. On-line optical sensing of blood volume changes to prevent intradialytic hypovolemia.Intradialytic hypovolemia is a common complication of hemodialysis treatments. blood volume changes that occur during dialysis can be followed by on-line optical sensing of the patient's hematocrit. Characteristic curves of blood volume changes can be seen in fluid overloaded patients with symptoms of hypovolemia, i.e. cramps, hypotension. The relative blood volume changes in those who have fluid removed to their ideal "dry" weight without symptoms will be shown in comparison. As Phase I of a CQI project, the nephrologist and dialysis nurses at the london health Sciences Centre performed a cross-sectional study to define the frequency of these curves and their relationship to intradialytic symptoms. The analysis of these curves can be used to re-assess "dry" weights, prevent intradialytic hypovolemia and decrease the use of antihypertensive agents. The correlation of our findings with the results of an independent hypotensive CQI study will be presented.- - - - - - - - - - ranking = 0.024201144030387keywords = hypotension (Clic here for more details about this article) |