PubMed Health⌕ Search

Biomedical subjects

J Rootman

Publications and source records attributed to J Rootman.

At least 109 records · Page 6Linked to original sources
PubMed1985

Ocular pharmacokinetics of subconjunctivally versus intravenously administered 6-mercaptopurine.

The levels of 6-mercaptopurine (6-MP) were measured in the anterior chamber aqueous, the vitreous and the serum of rabbits 0.5, 1, 2, 4, 8 and 12 hours following subconjunctival or intravenous injection of 10 mg/kg in 0.5 mL of saline, the maximum tolerated dose as determined experimentally. The mean peak concentrations of 6-MP in the aqueous and the vitreous respectively of the subconjunctivally injected eyes were 15 and 10 times those achieved in all the eyes following intravenous administration. The bioavailability of the drug over 12 hours was 21.67 micrograms/h in the aqueous and 22.22 micrograms/h in the vitreous following subconjunctival administration but only 1.47 and 3.50 micrograms/h respectively following intravenous administration. The serum concentration of 6-MP following subconjunctival injection was about half that following intravenous administration.

Absorption↗
PubMed1984

Color as a risk factor in iris melanoma.

We reviewed 23 iris melanomas for iris color and gross tumor pigmentation. Patients with iris melanoma had lighter irides than both population controls (x2 = 58.0; P less than .0001) and other patients with uveal melanoma (x2 = 17.1; P = .002). Amelanotic and lightly melanotic tumors occurred predominantly in the patients with light irides.

Eye Color↗
PubMed1984

The effect of age on the nerve fiber population of the human optic nerve.

Nerve fiber counts of 16 normal human optic nerves from subjects aged 3.5 to 82 years showed a significant effect of age (P = .0207). The delay between death or enucleation and fixation also significantly affected the result (P = .0078). The mean (+/- S.E.M.) count for the 16 nerves was 1,244,005 +/- 20,033 fibers, giving a 99% confidence level between 1,192,400 and 1,295,610 fibers.

Adolescent↗
PubMed1984

Polyclonal orbital and systemic infiltrates.

Two unusual cases of benign lymphoproliferative disease associated with orbital and systemic involvement are described. Both have occurred in adults with longstanding histories and clinical manifestations that have mimicked lymphomas. The orbital disease has been both antecedent and subsequent to the systemic lesions. These cases emphasize the spectrum of lymphoproliferative disorders and call attention to the possibility of multisystem disease in patients with benign lymphoproliferative lesions.

Aged↗
PubMed1984

Recent advances in pathology as applied to orbital biopsy. Practical considerations.

Advances in pathology allow for more specific diagnoses of orbital disease. The authors discuss the value of awareness of advances in cytology, histochemistry, immunohistochemistry and electron microscopy as applied to orbital disease. Modern cytologic technique can aid in clearer visualization of cellular detail with improved diagnosis of thin needle aspiration biopsies. Histochemistry offers an increasing range of methods for identification of cellular and extracellular substances such as amyloid, fibrin, neuroglia, and collagen. Immunohistochemistry allows for identification of an ever-increasing number of component antigens including immunoglobulins, myoglobins, keratin, glial fibre protein, etc. Electronmicroscopic technique including plastic embedding allow for specific identification of lesions based on subcellular components and characteristic nuclear, cytoplasmic, membrane, basement membrane and stromal components. The value of these methods has been demonstrated with case presentations of "small round cell tumors" of the adult and child. In addition, the pathologic diagnosis of several rare lesions of the orbit including neuroendocrine carcinoma, histiocytosis X, simultaneously occurring poorly differentiated mucoepidermoid carcinoma of lacrimal gland and adenocarcinoma of the prostate are demonstrated to underline the advances in technology. Emphasis is placed on the management of biopsy material to maximize diagnostic potential.

Aged↗
PubMed1984

Enophthalmos: a clinical review.

Twenty-six cases of enophthalmos were reviewed. The causes in order of frequency were: orbital asymmetry (8); trauma (5); orbital metastasis (4); microphthalmos (2); orbital varix (2); maxillary mucocele (2); localized scleroderma (1); absence of sphenoid wing (neurofibromatosis) (1); post irradiation atrophy (1). Only six of the patients (23%) were referred with the diagnosis of enophthalmos, suggesting the sign maybe subtle and is frequently missed or misdiagnosed. The nature of the causes underscore the need for careful and thorough diagnosis. In particular, the therapeutic implications of diagnosing metastatic disease, maxillary mucocele, and orbital varices is noted. A review of etiology and mechanisms of enophthalmos point to the diversity, importance and conditions causing this sign.

Adolescent↗
PubMed1984

Orbital dermoids: clinical presentation and management.

The authors have reviewed 15 cases of orbital dermoids representing 6% of orbital tumours seen at the University of British Columbia Orbital Clinic. They tended to occur as either asymptomatic superficial lesions in children or as complicated deep lesions in adolescents and adults. The superficial lesions were as frequent medially as laterally and could be dealt with by a direct uncomplicated surgical approach. The deep lesions in contrast, were frequently extensive and difficult to remove, requiring careful preoperative planning. Sites of origin, presentation, differential diagnosis, and management are discussed.

Adolescent↗
PubMed1984

Pharmacokinetics and metabolism of 5-fluorouracil following subconjunctival versus intravenous administration.

Two groups of six rabbits each were given 6.25 mg/kg of 6-carbon-14-labelled 5-fluorouracil (5-FU) either subconjunctivally or intravenously. The levels of the drug in the serum, the urine and the ocular humours 0.5, 1, 2, 4, 8 and 12 hours later were measured by high-pressure liquid chromatography, which distinguished between 5-FU and its metabolites. The peak levels of the parent drug in the serum and the urine were similar with the two routes of administration; however, compared with intravenous injection, subconjunctival injection resulted in 125 and 380 times the peak concentration of 5-FU in the anterior chamber aqueous and the vitreous respectively.

Animals↗
PubMed1983

Nodular sclerosing Hodgkin's disease of the orbit.

Hodgkin's disease is a rare occurrence in the orbit and, when present, has been seen in patients as part of the known systemic diasthesis usually in the terminal phase. A case of nodular sclerosing Hodgkin's with a long-standing lesion of the orbit leading to bony excavation in the lacrimal fossa is reported.

Adult↗
PubMed1983

Subconjunctival versus intravenous cytosine arabinoside: effect of route of administration and ocular toxicity.

The ocular penetration, elimination, and toxicity of equidose cytosine arabinoside (Ara-C) (37.5 mg/kg) following subconjunctival versus intravenous injection were compared in rabbits. Drug levels were measured at 0.5, 1, 2, 4, 8, and 12 hours in serum, urine, and ocular compartments. Following subconjunctival administration, the peak concentration of Ara-C in the anterior chamber was 15 times and in the vitreous twice that obtained following intravenous administration. Drug levels obtained were considered high enough to be effective in inhibiting the growth of selected tumor lines. The cumulative urinary excretion over 12 hours was 67% and 70% for the subconjunctivally and intravenously injected animals, respectively, and peak serum levels were 0.061 mM and 0.170 mM, respectively. Clinical and histologic toxicity following subconjunctival injection was minimal, and no bone marrow suppression was detected at the dose level administered.

Absorption↗
PubMed1983

Combined local chemotherapy for a spontaneously occurring intraocular tumour in a cat.

A spontaneously occurring tumour in the anterior chamber of the eye of a cat was diagnosed by aspiration needle biopsy as a malignant lymphosarcoma. Combined local chemotherapy, consisting of subconjunctival injection of methylprednisolone acetate and methotrexate along with topical administration of dexamethasone, led to rapid resolution of the lesion. Over 18 weeks of follow-up there was no recurrence.

17-Hydroxycorticosteroids↗
PubMed1983

An approach to diagnosis of orbital disease.

In spite of advances in investigative technology as applied to orbital disease, clinical judgement remains the most important tool in diagnosis. A model for a clinical approach to the diagnosis or orbital disease is presented in this paper. Defining the location of and the dynamic alteration induced by the disease sets the stage for investigation. The location of the disease is determined by changes induced in the position of orbital structures. Characterizing the dynamic alteration involves assessing evidence of temporal change and signs of the disease process--inflammation, a mass effect or infiltration. Synthesis of the information gained will improve clinical judgement.

Diagnosis, Differential↗
PubMed1982

Ocular absorption and toxicity of a radiosensitizer and its effect on hypoxic cells.

The recurrence of retinoblastoma after radiation treatment may be related to hypoxic cell radioresistance. Radiosensitizing drugs acting on hypoxic cells without affecting the response of oxygenated cells could improve treatment of ocular tumors while minimizing complications of radiotherapy. A desmethyl derivative of misonidazole is as effective a radiosensitizer as misonidazole (as measured in vitro) and is better suited to ocular administration, since it is more soluble than misonidazole. We studied the ocular toxic effects of a desmethyl derivative of misonidazole after subconjunctival administration of 140 and 70 mg. The higher dose produced an intolerable ocular toxic effect, but at the lower dose, the toxic effect was moderate and reversible. We compared ocular pharmacokinetics of the desmethyl derivative of misonidazole after subconjunctival and intravenous (IV) injections. Subconjunctival administration yielded vitreous and anterior chamber concentrations of the radiosensitizer sufficient to produce a notable dose-modifying effect (as high as 1.8 in the anterior chamber and 1.25 in the vitreous at 70-mg doses). In contrast, even at doses of 140 mg, IV injections of the desmethyl derivative of misonidazole did not result in therapeutically useful ocular levels.

Animals↗
PubMed1982

The classification and management of acute orbital pseudotumors.

The clinical presentation, investigative findings, classification, and management of 17 acute pseudotumors based on patterns of orbital involvement is presented. Acute pseudotumors developed over days to weeks and were dominated by pain, neuropraxia, and inflammatory clinical features. Five patterns of acute inflammatory pseudotumor were seen. Anterior and diffuse acute pseudotumors were characterized by manifestations of inflammation of the globe and orbit including pain, lid swelling, ptosis, diplopia, uveitis, papillitis, optic neuropathy, and exudative retinal detachment. Anterior or diffuse orbital infiltration was noted on computerized tomography (CT) and ultrasound. Lacrimal involvement was characterized by local pain, tenderness, lid swelling and inflammation, with CT and ultrasound confirming an anterior inflammatory mass. Posterior or apical involvement led to an early optic neuropathy, and myositic lesions were characterized by features of muscle infiltration. Management with steroids was effective and could be followed by serial CT studies.

Acute Disease↗
PubMed1982

Primary orbital schwannomas.

Seven histologically proved cases of primary orbital schwannoma have been seen at the University of British Columbia Orbital Clinic between September 1976 and December 1980. We describe here their varied clinical presentations, preoperative investigations, operative findings, and appearances on light and electron microscopy. Although no single feature is pathognomonic, a multiplicity of clinical, radiographic, and surgical features point to this lesion. Of preoperative investigations the computed tomography scan was the most helpful, especially in localising the lesion. Of the 7, 4 were intraconal and 3 were extraconal. The surgical approach was dictated by tumour site and included anterior, lateral, and panoramic orbitotomies. At surgery the nerve of origin of 4 of the tumours was identified. All tumours were excised totally or subtotally. There has been no recurrence to date.

Adult↗
PubMed1982

Bilateral retinal infarction in disseminated aspergillosis.

A 10-month-old boy presented with malnutrition and fever of unknown origin. Treatment with steroids, antibiotics and total parenteral nutrition was unsuccessful, and progressive thrombotic complications led to death in 5 weeks. An antemortem diagnosis of embolic occlusion of both central retinal arteries was confirmed at autopsy. Aspergillus had invaded the blood vessels of many organs, including the eyes, and had proliferated within their lumina, causing thrombi and emboli to form and resulting in extensive tissue infarction, necrosis and hemorrhage.

Aspergillosis↗