1/89. epinephrine-induced potentially lethal arrhythmia during arthroscopic shoulder surgery: a case report.Arthroscopic shoulder surgery performed on a healthy female could have resulted in a fatal outcome when the epinephrine present in the arthroscopic irrigating solution contributed to the onset of ventricular tachycardia requiring defibrillation during surgery. During this procedure, the shoulder was infiltrated with 30 mL of a 1:100,000 solution of epinephrine into the subacromial space and glenhumeral joint. Subsequently, instrumentation of the glenhumeral joint by the orthopedic surgeon with a standard arthroscopy trocar resulted in a 0.5-cm size lesion to the posterior humeral cortex. Minutes after the start of the surgical procedure, the patient displayed an abrupt onset of ventricular tachycardia and hypertension. These signs and symptoms suggested an intraosseous infusion of both infiltrated and irrigation solution containing epinephrine through the lesion in the humeral cortex. Approximately 800 mL of a .01 mg/mL concentration of irrigation solution containing epinephrine was used. A diagnosis of epinephrine-induced ventricular tachycardia was made. The arthroscopic irrigating solution was immediately discontinued and lidocaine, 100 mg intravenously, was administered; however, the patient's cardiac rhythm degenerated into a sustained ventricular tachycardia that was unresponsive to pharmacologic intervention. A full code was called; the surgeon, anesthesia team, and operating room personnel succesfully provided advanced cardiac life support and cardioverted the patient back into a sinus rhythm with no untoward effects.- - - - - - - - - - ranking = 1keywords = posterior (Clic here for more details about this article) |
2/89. Posterior-fossa haemorrhage after supratentorial surgery--report of three cases and review of the literature.We present clinical details of three patients with posterior fossa haemorrhage after supratentorial surgery and discuss possible pathomechanisms of this rare complication. All patients were males of advanced age. Two patients presented with a history of hypertension. In all patients the occurrence of haemorrhage was associated with loss/removal of large amounts of cerebrospinal fluid (CSF) either intra-operatively (one patient undergoing aneurysm surgery) or postoperatively (all three patients: drainage of subdural hygromas or chronic subdural haematomas in two, external ventricular drainage in one patient). Treatment consisted in haematoma evacuation and/or external ventricular drainage. Two patients died, one patient recovered completely. Although haematomas distant from a craniotomy site are a well known entity, a review of the literature identified only 25 published cases of posterior fossa haemorrhage after supratentorial procedures in the CT era. Most often disturbances of coagulation, positioning of the patient and episodes of hypertension have been associated with this complication. Only one author described the occurrence of a haemorrhage after drainage of a supratentorial hygroma. We suggest that the loss of large amounts of CSF intra-operatively and post-operatively may lead to parenchymal shifts or a critical increase of transmural venous pressure with subsequent vascular disruption and haemorrhage.- - - - - - - - - - ranking = 2keywords = posterior (Clic here for more details about this article) |
3/89. Assessment of vasogenic edema in eclampsia using diffusion imaging.We qualitatively assessed the regional distribution of vasogenic edema in a case of postpartum eclampsia. Although diffusion-weighted imaging showed no abnormalities, bilateral high signal was seen on T2-weighted images and apparent diffusion coefficient (ADC) maps. ADC of 1.45 /- 0.10 mm2/s x 10(-3) for the posterior cerebral artery (PCA) territory and 1.22 /- 0.12 mm2/s x 10(-3) for the watershed areas were significantly higher than those in the territories of the anterior (0.85 /- 0.07 mm2/s x 10(-3) and middle cerebral (0.79 /- 0.06 mm2/s x 10(-3)) arteries (P < 0.05). The predilection of ADC changes within the PCA territory and in a previously undescribed watershed distribution supports the hypothesis that vasogenic edema in eclampsia is due to hypertension-induced failure of vascular autoregulation.- - - - - - - - - - ranking = 1keywords = posterior (Clic here for more details about this article) |
4/89. Severe postpartum hypertension and reversible cerebral angiopathy associated with ergot derivative (methergoline) administration.A 36-year-old woman (gravida 2, para 2) delivered a healthy child by cesarean section at the 37th week of an unremarkable gestation. blood pressure remained within normal range throughout the pregnancy, surgery, and for the 9 following days. On day 10, about 36 hours after the initiation of oral methergoline to suppress lactation, the patient complained of severe posterior headache, flashing scotomata, hypertension, tonico-clonic seizures and then homonymous left hemianopsia and hemiparesis. blood pressure monitoring confirmed intermittent and severe hypertension. angiography demonstrated diffuse narrowing of the small and medium cerebral arteries. Transcranial Doppler ultrasound examination disclosed a bilateral increase in mean flow velocity. Progressive normalization of blood pressure, obtained with labetalol and oral clonidine, was accompanied by amelioration of the neurological deficits until a complete recovery and normalization of transcranial Doppler flow velocity occurred. This case provides further evidences that hypertension might play a major pathogenetic role in reversible cerebral angiopathy. Some ergot derivatives (including methergoline) might trigger the initial rise in blood pressure.- - - - - - - - - - ranking = 1keywords = posterior (Clic here for more details about this article) |
5/89. Reversible posterior leukoencephalopathy syndrome in hepatitis c virus-positive long-term hemodialysis patients.Chronic hepatitis c virus (HCV) infection is quite prevalent in long-term hemodialysis (HD) patients. patients who are candidates for renal transplantation might be treated, before grafting, with interferon-alpha (IFN-alpha). Among 39 HCV-positive long-term HD patients treated with IFN-alpha, we observed three cases of reversible posterior leukoencephalopathy syndrome (PLES). PLES included headaches in three patients, confusion in three patients, cortical blindness in two patients, visual hallucinations in one patient, seizures in three patients, and respiratory distress in one patient in a context of fluid overload and severe hypertension in all cases. The three patients were receiving IFN-alpha and recombinant erythropoietin therapies simultaneously for de novo anemia. Contrast-enhanced computed tomography scan or magnetic resonance imaging showed low-density areas in the occipital lobes (in three patients), frontal lobes (in one patient), and temporal lobes (in one patient). After withdrawal of IFN-alpha and recombinant erythropoietin therapies, hemodiafiltration, and symptomatic treatment of seizures and hypertension, PLES was reversible within 1 week in one patient, 10 days in one patient, and 2 months in the third patient. Our case reports show the occurrence of reversible PLES in HCV-positive long-term HD patients treated with IFN-alpha. physicians caring for HCV-positive long-term HD patients treated with IFN-alpha need to be particularly cautious when these patients receive simultaneously recombinant erythropoietin and when IFN-alpha therapy induces a weight loss, which indicates a reduction in dry weight.- - - - - - - - - - ranking = 15861.434388903keywords = leukoencephalopathy syndrome, posterior leukoencephalopathy syndrome, posterior leukoencephalopathy, leukoencephalopathy, posterior (Clic here for more details about this article) |
6/89. Reversible posterior leukoencephalopathy in a patient with minimal-change nephrotic syndrome.A 9-year-old boy with nephrotic syndrome was transferred to our hospital because of acute renal failure and disturbance of consciousness after high-dose methylprednisolone therapy. He developed severe headache, visual disturbance, and generalized seizures. Brain computed tomography (CT) scan revealed multiple, bilateral, low-density areas in the parieto-occipital lobes. magnetic resonance imaging (MRI) disclosed a high signal intensity area on T2-weighted images and a low signal intensity area on T1-weighted images in the same lesion. Follow-up brain CT scan and MRI, 2 weeks after the first studies, showed complete resolution of the abnormal lesions, which suggested the diagnosis of reversible posterior leukoencephalopathy syndrome (RPLS). hypertension and high-dose methylprednisolone administration to the patient in the nephrotic state may be causes of this uncommon syndrome in this case. This is the first report of RPLS in nephrotic syndrome with hypertension not associated with cyclosporine administration.- - - - - - - - - - ranking = 4903.9422572079keywords = leukoencephalopathy syndrome, posterior leukoencephalopathy syndrome, posterior leukoencephalopathy, leukoencephalopathy, posterior (Clic here for more details about this article) |
7/89. Transient posterior encephalopathy induced by chemotherapy in children.The cases of three children, 16, 12, and 12 years of age, who suffered sudden confusional state and cortical blindness lasting 12 to 30 minutes while under treatment with high-dose methotrexate, cyclophosphamide, and dactinomycin for a lower limb osteosarcoma are reported. Transient neuropsychologic deficits arose after the acute phase of treatment: left hemispatial neglect and constructive apraxia (Patient 1); constructive apraxia (Patient 2); and constructive apraxia and alexia without aphasia (Patient 3). The three patients recovered completely from all their deficits within the time frame of 3 hours to 2 weeks. Arterial hypertension and hypomagnesemia were found during the acute phase in all patients. In patients 2 and 3, magnetic resonance imaging revealed increased parieto-occipital T(2) signal involving gray and white matter. In patients 1 and 2, HmPAO-SPECT revealed parieto-occipital hypoperfusion that resolved a few days later. The alterations detected by neuroimaging were concurrent with the appearance and disappearance of the clinical symptoms. Such transient acute episodes have been named occipital-parietal encephalopathy. On the basis of our clinical, laboratory, and neuroimaging findings, an explanation for the origin of this syndrome, a migrainelike mechanism, triggered by chemotherapy-induced hypomagnesemia, is proposed.- - - - - - - - - - ranking = 4keywords = posterior (Clic here for more details about this article) |
8/89. Reversible posterior leucoencephalopathy syndrome in systemic lupus and vasculitis.OBJECTIVES: Reversible posterior leucoencephalopathy syndrome (RPLS) may develop in patients with renal insufficiency, hypertension, and immunosuppression, and is managed by prompt antihypertensive and anticonvulsant treatment. Four patients with renal insufficiency and fluid overload associated with Wegener's granulomatosis (one patient) and systemic lupus erythematosus (SLE) (three patients) are described, whose clinical picture and neuroimaging indicated RPLS. case reports: All patients had headache, seizures, visual abnormalities, and transient motor deficit, and were hypertensive at the onset of the symptoms. Head computed tomography (CT) scan and magnetic resonance imaging showed predominantly posterior signal abnormalities, which were more conspicuous on T(2) weighted spin echo images than on CT scan. All patients had some form of cytotoxic treatment shortly before the syndrome developed, and dramatically responded to blood pressure control and anticonvulsant treatment. In two patients with SLE, dialysis was required for renal insufficiency. DISCUSSION: Follow up neuroimaging studies showed almost complete resolution of signal abnormalities, and suggested that RPLS was associated with cerebral oedema without concomitant infarction. The treatment of hypertension and neurotoxic condition such as uraemia appears of primary importance, while immunosuppressive treatment may cause further damage of the blood-brain barrier.- - - - - - - - - - ranking = 6keywords = posterior (Clic here for more details about this article) |
9/89. Ultra high field MRI at 8 Tesla of subacute hemorrhagic stroke.PURPOSE: Optimal treatment strategies and neurologic outcome after stroke depend on an accurate characterization of the lesion. There is a need for high resolution noninvasive imaging for assessment of the infarct size, perfusion, and vascular territory. MRI at the ultra high field (UHF) of 8 T offers unprecedented resolution, but its utility for stroke evaluation has not been determined yet. METHOD: A 55-year-old man with hypertension experienced sudden onset of speech arrest and right-sided hemiparesis that resolved in < 24 h with minimal neurologic deficit. MRI at 1.5 T showed initially a left posterior frontal lesion with subacute infarct (hyperintense on T2-weighted spin echo images) and right-sided frontal and periventricular lesions consistent with chronic infarct. There were many smaller white matter lesions. Delayed studies showed high signal changes involving the gray matter only on T1-weighted images. RESULTS: Gradient echo and rapid acquisition with relaxation enhancement (RARE) multislice images revealed a serpentine area of low signal in the left posterior frontal lobe gray matter suggestive of a hemorrhagic infarct, right-sided frontal lesion also showing iron deposits, multiple periventricular and cortical areas with abnormal high signal regions that were consistent with old infarcts, and numerous small vessels readily visible, more prominent on the right. CONCLUSION: MRI at 8 T displays lesions with a high resolution and striking anatomic details. Susceptibility to iron and sensitivity to detect blood products are increased at 8 T. The imaging characteristics at high field are different from those at low field, but both represent findings of iron products.- - - - - - - - - - ranking = 2keywords = posterior (Clic here for more details about this article) |
10/89. aneurysm of the posterior inferior cerebellar arteries/communicating artery.Only 3 cases of aneurysm associated with the communicating artery between both distal posterior inferior cerebellar arteries (PICAs) have been reported in the literature. We present the 4th case of such an aneurysm arising from the communicating artery itself, which is unrelated to the arterial branches. A hypertensive 68-year-old man presented with a Hunt and Hess grade 4 subarachnoid hemorrhage. Angiographic studies revealed that the ruptured aneurysm arose from the fine communicating artery itself interconnecting both distal pica vermian branches. The right pica was absent and its vermian territory was supplied by the left pica through this communicating artery. At surgery, a saccular aneurysm was noted which developed at the top of the arterial loop under the nodulus of the cerebellar vermis and was trapped. The actual prevalence and clinical significance of aneurism associated with the communicating artery interconnecting both PICAs are unknown, but defective embryonal development may lead to congenital vulnerability of the vascular wall, resulting in aneurysm formation.- - - - - - - - - - ranking = 5keywords = posterior (Clic here for more details about this article) |
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