Biomedical subjects
M A Novak
Publications and source records attributed to M A Novak.
Transient hearing loss with metrizamide.
Two case studies are reported in which transient low frequency sensorineural hearing loss was experienced following myelography and CT scanning with metrizamide. Low frequency sensorineural hearing loss is considered to be the result of increased stiffness of one or both of the inner ear membranes. A review of the literature regarding an osmotic relationship between blood, cerebrospinal fluid, and the inner ear fluids attempts to explain how this phenomenon may have occurred with metrizamide. The transient sensorineural loss observed in the case studies presented is compared to the pathophysiology attributed to the formation of endolymphatic hydrops.
Successful treatment of postoperative Candida endophthalmitis in an eye with an intraocular lens implant.
Candida endophthalmitis developed in the left eye of a 71-year-old man two months after he underwent extracapsular cataract extraction and intraocular lens implantation. The symptoms included decreased vision and redness but no pain. The discovery of the cause of the endophthalmitis was delayed because it was initially treated as a sterile postoperative inflammation. Vitrectomy with intracameral amphotericin B and treatment with topical and systemic amphotericin B and flucytosine led to resolution of the infection and a final visual acuity of 20/80. It was not necessary to remove the intraocular lens.
Complications of acute symptomatic posterior vitreous detachment.
During a ten-year period, 172 eyes of 155 patients developed acute symptomatic posterior vitreous detachments. The study included only patients examined within three months of the onset of symptoms. The patients ranged in age from 22 to 82 years, with an average age of 60 years. Of the 172 eyes, 118 (69%) developed no retinal or vitreous complications. Retinal tears occurred in 14 eyes (8%) and vitreous or retinal hemorrhages occurred in 36 eyes (21%). Seventeen patients (11%) who had acute symptomatic posterior vitreous detachment in one eye later developed acute symptomatic posterior vitreous detachment in the fellow eye. The second posterior vitreous detachment developed within two years of the first one in 15 eyes (88%). In 13 patients (76%), the second eye responded in the same manner to the posterior vitreous detachment as had the first, that is, ten pairs of eyes had no further complications, two pairs had retinal or vitreous hemorrhages, and one pair had retinal breaks.
Vitreous hemorrhage after vitrectomy for diabetic retinopathy.
The records of 596 consecutive vitrectomy cases performed for complications of diabetic retinopathy were reviewed to determine the incidence of intraoperative and postoperative vitreous hemorrhage and to determine if blood cleared more rapidly in aphakic compared to phakic eyes. Uncontrollable intraocular bleeding occurred in two eyes (0.5%). Vitreous hemorrhage was present on the first postoperative day in 278 eyes (63%). This early hemorrhage cleared in an average of 9.1 weeks in phakic eyes and 3.4 weeks in aphakic eyes. Further vitreous hemorrhage occurred in 88 eyes (23%). Sixty-four percent of later hemorrhages occurred in 88 eyes (23%). Sixty-four percent of later hemorrhages occurred within six months of the operation and 80% occurred within one year. Later vitreous hemorrhage cleared in an average of 16.2 weeks in phakic eyes and 5.3 weeks in aphakic eyes. Of the 311 eyes with vitreous hemorrhage at some time during the postoperative course, twenty-nine eyes (9%) underwent reoperation to remove nonclearing blood. Nonclearing vitreous hemorrhage was the main cause of final visual loss in only 15 (3.4%) of 438 eyes with adequate follow-up, and 6 of these 15 eyes had final vision of 5/200 or better.
The crystalline lens after vitrectomy for diabetic retinopathy.
We reviewed the records of 596 consecutive cases of vitrectomy performed for complications of diabetic retinopathy at the Wilmer Eye Institute. Accidental lens damage occurred during surgery in three eyes. Fourteen (8%) of 180 phakic eyes underwent later cataract removal. Follow-up of at least six months and detailed description of the lens at final examination were available in 151 eyes. Of these, visually significant opacities occurred in 32 eyes (21%), and the lens opacities accounted for substantial loss of final vision in 6 (19%) of these 32 eyes. Moderate or severe lens opacities that developed postoperatively were as follows: anterior subcapsular or cortical changes in 2 eyes (1%), nuclear sclerosis in 11 eyes (7%), posterior subcapsular changes in 25 eyes (17%). One hundred twenty-five preoperative, operative and postoperative factors were analyzed for each patient to detect correlations with postoperative lens changes. Nuclear sclerotic changes correlated with older patient age. Posterior subcapsular changes correlated with three intraoperative factors: longer duration of the operation, use of intravitreal gas, and use of a gas bubble filling more than 50% of the vitreous cavity. Posterior subcapsular changes were progressive with longer follow-up.
Ophthalmological manifestations: a case of familial giant cell arteritis.
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The rabbit properdin system: I. Identification of a new factor and purification of rabbit properdin.
Pure preparations of rabbit properdin were obtained from rabbit serum by ion-exchange chromatography. These preparations functioned as properdin when they were measured with the zymosan assay or with a serum reagent selectively depleted of properdin by a specific immunoabsorbent. Properdin in these preparations was in its activated state. A new serum factor was required to measure properdin activity when purified preparations of rabbit properdin were tested with the zymosan assay. This factor was designated as ZBP, or zymosan-binding protein. ZBP appeared to be distinct from known components of the alternative complement pathway and the classical complement system, and it did not appear to be an immunoglobulin.
Behavioral and hormonal effects of attachment object separation in surrogate-peer-reared and mother-reared infant rhesus monkeys.
Mother-reared and surrogate-peer-reared rhesus monkeys were separated from their respective attachment objects at 6 months of age and tested for the following 9 weeks to determine their home-cage behavior and their pituitary-adrenocortical responses to stress. Both groups displayed a strong immediate behavioral response to separation which was characterized by increased vocalization, increased locomotion, and decreased self-play. However, the surrogate-peer-reared infants showed a subsequent recovery in their levels of self-play whereas the mother-reared infants instead developed stereotypic behavior patterns such as repetitive pacing. The 2 groups displayed similar plasma cortisol responses to weekly sessions in an apparatus equipped with animated toy "monsters". Mother-reared but not surrogate-peer-reared subjects, however, also manifested elevated cortisol levels when an animal in an adjacent cage was captured and removed for stress testing. Mother-reared infant monkeys thus responded in a stronger and more prolonged manner to the loss of their attachment object than surrogate-peer-reared infants. These results suggest that infant rhesus monkeys form stronger attachments to monkey mothers than to inanimate surrogate mothers, a phenomenon which has not been as clearly demonstrated using other indices of attachment strength.
Psychopathological perspectives.
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