Biomedical subjects

Misha Pless

Publications and source records attributed to Misha Pless.

9 recordsLinked to original sources

PubMed2005

The use of acetazolamide in idiopathic intracranial hypertension during pregnancy.

PURPOSE: To describe the pregnancy outcomes after the use of acetazolamide in pregnant patients with idiopathic intracranial hypertension (IIH). DESIGN: Observational case series. METHODS: setting: Two tertiary care academic neuro-ophthalmology units. patient population: Patients with IIH treated with acetazolamide. observation procedure: Documentation of pregnancy outcome. main outcome measures: Normal pregnancy, fetal loss, or congenital malformation. RESULTS: Twelve patients were treated with acetazolamide for IIH during pregnancy, and there were no adverse pregnancy outcomes. A critical review of the English language literature on the subject failed to demonstrate any convincing evidence for any adverse effect on pregnancy for acetazolamide. CONCLUSIONS: Acetazolamide at high doses may produce birth defects in animals, but there is little clinical or experimental evidence to support any adverse effect of the drug on pregnancy outcomes in humans. If the clinical situation warrants the use of acetazolamide in IIH, then the drug probably can be offered after appropriate informed consent.

Acetazolamide↗

PubMed2004

Sympathetic and parasympathetic innervation of pupillary dilation during sustained processing.

The contributions of separate sympathetic and parasympathetic pathways to pupillary dilation during a sustained processing task were studied through environmental and pharmacological manipulations. In Experiment 1, 22 healthy volunteers (11 female) performed a serial Subtract 7 task while pupil diameter was recorded both during moderate room light and in darkness. In a control for verbalization, subjects performed an easier Add 1 task. In all conditions, pupil diameter increased significantly during the response period as compared to a pre-verbalization baseline period. Pupillary dilation was increased for the difficult task, and further increase in dilation was associated with recording in light. This suggests a major differential contribution to task difficulty mediated through inhibition of the parasympathetic pathway. In Experiment 2, a subgroup of 12 volunteers (seven female) repeated all conditions at three additional sessions in which one eye was instilled with tropicamide (to block the parasympathetic sphincter muscle), dapiprazole (to block the sympathetic dilator muscle) or placebo. All pharmacological conditions resulted in overall dilation during task performance. Differential performance similar to the placebo condition was seen only in the dapiprazole condition, when parasympathetic activation was intact. The findings suggest that sustained performance during a difficult task is modulated by cortical inhibition of the parasympathetic pathway at the oculomotor nucleus. Moreover, modulation of both ambient light intensity and pharmacological blockade of the final pupillary musculature were observed to provide converging approaches for quantifying the activity of identifiable central autonomic pathways.

Adult↗

PubMed2003

Rosai-Dorfman disease. Extranodal sinus histiocytosis in three co-existing sites. A case report.

A 73-year-old woman presented with mild anterior uveitis, ipsilateral optic neuropathy, and ipsilateral skin nodules. A compressive mass at the level of the orbital apex and sphenoid wing was found on cranial magnetic resonance imaging. Biopsy of the skin nodules revealed histopathologic evidence of sinus histiocytosis with massive lymphadenopathy, or Rosai-Dorfman disease (RDD). Systemic investigations failed to show any massive lymphadenopathy, making this a case of extranodal RDD. This is a salient case in that it proposes three simultaneous and separate sites of involvement by extranodal RDD. It also exemplifies that RDD should be a suspect diagnosis even in the absence of lymphadenopathy.

Aged↗

PubMed2003

Topical phenylephrine may result in worsening of visual loss when used to dilate pupils in patients with vaso-occlusive disease of the optic nerve.

Four patients (age range 54-82, 1F 3M) diagnosed with non-arteritic ischemic optic neuropathy experienced acute worsening of visual function after instillation of phenylephrine for dilated funduscopic examination. They experienced decreased visual function immediately or shortly after administration of topical mydriatic drops given in preparation for funduscopy. In all cases one drop each of 2.5% phenylephrine and 0.5-1% tropicamide was used. Three patients had classical risk factors such as hypertension, diabetes, and had a contralateral "disc-at-risk". The female and youngest patient had ischemic optic neuropathy presumed secondary to lupus erythematosus. The time from acute visual loss to presentation to neuro-ophthalmic care ranged from 1-6 days. The time of onset of the decline in visual function varied from 45 minutes (patient with lupus) to 12 hours after instillation of mydriatic drops. Visual acuity at diagnosis ranged from 20/40-20/400. Phenylephrine is a mydriatic with vasoconstrictive properties, which may be absorbed through the cornea, thus yielding non-negligible intraocular concentrations. Vasoconstriction of the watershed posterior ciliary capillary beds may result in further precipitating infarction of already compromised circulatory territories in edematous optic nerves. Because phenylephrine is a known vasoconstrictor in vivo and in vitro, it is more likely to cause deleterious vasoconstriction and an acute decline in visual function in patients with acute ischemic optic neuropathy than tropicamide. The routine practice of using phenylephrine to prepare patients for funduscopic assessment should be re-examined, particularly in patients with ischemic optic neuropathy.

Administration, Topical↗

PubMed2003

Apoplectic lymphocytic hypophysitis. Case report.

Pituitary apoplexy has not been reported in the setting of lymphocytic hypophysitis. The authors present the case of a woman with sudden vision loss and headache. Magnetic resonance imaging revealed focal hemorrhages in a sellar lesion with suprasellar extension. The results of histopathological analysis were consistent with lymphocytic hypophysitis.

Adult↗

PubMed2003

Alcohol embolization of carotid-cavernous indirect fistulae.

OBJECTIVE: Carotid-cavernous fistulae (CCFs) are abnormal communications between the carotid artery and cavernous sinus that may present with rapid visual deterioration and extraocular paresis as a result of increasing intraocular pressure requiring emergent treatment to preserve vision. We present a technique of balloon-assisted ethanol embolization of the cavernous carotid artery supply to indirect CCFs providing immediate reduction in intraocular pressure with symptomatic improvement. METHODS: We reviewed clinical and angiographic data and present a retrospective case series illustrating six patients who underwent endovascular embolization because of worsening visual acuity and extraocular motility disorder caused by CCFs. Cerebral angiography revealed significant blood supply from the cavernous carotid artery to these CCFs. We performed ethanol embolization of these branches with distal balloon protection. RESULTS: Five of the six patients experienced immediate and sustained (mean follow-up, 21 mo) decreases in intraocular pressure, with significant symptom improvement. One patient experienced cavernous sinus thrombosis after conclusion of embolization, which caused a temporary worsening of symptoms that improved gradually over time. CONCLUSION: Many surgical and endovascular options are available to treat indirect CCFs. Absolute ethanol is a liquid agent that causes immediate vessel sclerosis and occlusion, which makes it a dangerous but potent liquid embolic agent. With distal temporary balloon protection to prevent migration of ethanol, we achieved excellent clinical and angiographic results using absolute ethanol to embolize the cavernous carotid supply to indirect CCFs. This represents a safe and effective method of endovascular management of this complex vascular anomaly.

Aged↗

PubMed2002

Orbital apex syndrome: a rare presentation of extramedullary hematopoiesis: case report and review of literature.

We describe a case of compressive neuropathy in the orbital apex due to extramedullary hematopoiesis (EMH). A 64-year-old man with Polycythemia Rubra Vera developed unilateral visual loss, proptosis, complete ophthalmoplegia, and facial paresis. Bone marrow biopsy showed myelofibrosis. Magnetic resonance imaging demonstrated enhancement at the orbital apex and subtle optic canal narrowing. Decompression of the optic nerve with biopsy of surrounding bone showed EMH. The patient received a course of radiation without benefit. We suggest including the diagnosis of EMH of the orbital apex bones in the differential diagnosis of patients with myeloproliferative disorders who develop an orbital apex syndrome.

Facial Paralysis↗

PubMed2002

Small B-cell lymphoma presenting as diffuse dural thickening with cranial neuropathies.

The authors present a rare case of diffuse hypertrophy of the pachymeninges due to lymphomatous dural infiltration. This lymphoma arose late after orthotopic liver transplant, was Epstein-Barr virus (EBV)-negative, and arose in a setting of prior hepatitis C infection, a condition that may contribute to development of some non-Hodgkin's lymphomas. Biopsy of the dura demonstrated a small B-cell lymphoma, immunophenotypically most similar to those of mucosa-associated lymphoid tissues (MALT). Rapid expansion of the dura in this case resulted in profound hyperesthesia of the scalp, progressive blindness, deafness, and ataxia. As expected for MALT-lymphomas clinical symptoms responded well to cranial radiation.

Aged↗

PubMed2002

Neurologic complications of transplantation.

BACKGROUND: Organ transplantation is one of the most dynamic fields in medicine and has evolved into a life-saving option for thousands of patients with previously fatal conditions. The posttransplantation clinical course is frequently associated with neurologic complications that are usually related to pretransplant morbidity, the surgical procedure of transplantation, immunosuppression, and opportunistic infection. REVIEW SUMMARY: Neurologic complications of organ transplantation may be divided into complications common to all types of allografts and complications that are specific for a particular type of organ transplantation. The most common complications include seizures, opportunistic central nervous system (CNS) infection, metabolic encephalopathy, stroke, intracranial hemorrhage, and drug-related adverse events. Opportunistic CNS infection may have a subtle presentation and should not be overlooked, as the consequences of delayed treatment may be grave. Neurotoxicity of immunosuppressive agents is also a frequent cause of neurologic complications and may occur in the setting of normal serum drug levels. The clinical course of transplant patients is frequently complex, requiring close cooperation between the transplant team and specialty consultants. Prolonged survival of transplant patients will shift the focus of neurologic complications from acute, perioperative to chronic complications of immunosuppression. CONCLUSIONS: Neurologic complications of organ transplantation are commonly related to opportunistic infection or neurotoxicity of immunosuppressive agents, requiring careful titration of immunosuppression. Timely diagnosis of CNS infection or other causes of neurologic dysfunction may significantly improve recovery and outcome in these patients.

Journal Article↗