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Biomedical subjects

J T Zajtchuk

Publications and source records attributed to J T Zajtchuk.

28 records · Page 2Linked to original sources
PubMed1978

Melanotic neuroectodermal tumor of infancy.

The lack of knowledge regarding the histogenesis of the melanotic neuroectodermal tumor of infancy may account for the numerous names given to this neoplasm. The most appropriate nomenclature is melanotic neuroectodermal tumor of infancy as this term is both clinically descriptive and reflects its most likely histogenesis. The histological diagnosis of this neoplasm and its known benign biological behavior should be appreciated so that radical surgery or radiotherapy is not undertaken. Our case report includes an electron microscopic analysis which is in keeping with other reported cases. We have not confirmed high urinary VMA levels prior to resection of the lesion.

Female↗
PubMedDate not supplied

Incidence of Wharton's duct stenosis in floor of the mouth cancers excised with scalpel or cautery vs CO2 laser.

Surgery of the floor of the mouth (FOM) using a scalpel or cautery has produced stenosis of Wharton's duct, necessitating further surgery because of painful enlargement to the gland or suspected metastasis. The laser has been proposed as an alternative method that might avoid this complication. A retrospective study comparing these excisional techniques was done at Walter Reed Army Medical Center between 1973 and 1983. Of a total of 58 lesions, 35 were T1N0M0 and 23 were T2N0M0 (two synchronous lesions being present). Of 35 lesions excised with a scalpel, 11 had an associated submandibular gland resection. Of the remaining 25, two developed secondary duct stenosis. Of 10 lesions excised with cautery, three had an associated excision of the submandibular gland. Of the remaining seven, two developed stenosis and one required subsequent excision of the gland. Of 12 lesions excised with laser, four developed stenosis and two required subsequent excision of the gland. Laser excision appears to be of no advantage in avoiding further surgery of the submandibular gland. A submandibular gland resection at the time of the original resection of T1N0 or T2N0 cancers of the FOM does not appear warranted.

Constriction, Pathologic↗
PubMedDate not supplied

Osteogenesis imperfecta congenita and tarda: a temporal bone report.

The temporal bone report of an operated case of osteogenesis imperfecta tarda is presented. Histological examination confirmed the presence of bilateral fixation of the footplate by otosclerosis as the cause of the conductive hearing loss. Fragility of bony septae in the mastoid and of the stapedial crura were observed. Sensorineural impairment in later years with a reduction in neural elements in the cochlea appear related to the extent and activity of the otosclerotic foci. Additional temporal bone reports of three cases of osteogenesis imperfecta congenita show lack of deposition of the skein-like bone in the endochondral layer, sparse bony septae in marrow spaces and deficiency of the perosteal layer. The stapedial crura were thin and in two cases both were deformed and fractured.

Aged↗
PubMedDate not supplied

Hearing loss in relation to physical properties of middle ear effusions.

Hearing loss was measured in cats after ligation of the eustachian tube (ET) on one side to produce middle ear effusions. Auditory nerve responses to broad-band clicks were recorded from the ear canal. Plots of N1 response amplitude and latency versus click sound pressure level (SPL) were constructed. Hearing loss was determined as the average displacement along the SPL axis of the latency plot, relative to a previously recorded control series. Viscosity of effusion was measured with a cone and plate viscometer. Specific gravity was measured using a 1 cc pycnometer. Middle ear pressure was assessed tympanographically. After ET ligation, all cats developed negative middle ear pressure within three days and flat (type B) tympanograms within seven days. Hearing loss also developed early and became maximal at about three weeks. Tympanocentesis yielded either thin fluid or glue-like effusions in nearly equal numbers. The data indicate there is not a significant difference between the amount of hearing loss associated with thin fluids or with glue. Viscosity is not clearly related to the duration of time the fluid is present in the middle ear. There is a significant positive correlation between the amount of hearing loss and the volume of fluid present in the middle ear. Thus, the amount of hearing loss appears to depend only on the volume of effusion and is not significantly dependent on other physical properties of the fluid.

Animals↗
PubMedDate not supplied

The tricyclic trimipramine in the treatment of subjective tinnitus.

We examined 26 consecutive patients with subjective tinnitus. All subjects were treated with the tricyclic antidepressant trimipramine in a double-blind study, each subject acting as his own control. All subjects were evaluated with pure tone audiometry, site of lesion testing, and auditory brain stem evoked response. The tinnitus assessment consisted of frequency and intensity matching, the determination of masking levels, and a subjective evaluation of severity. Plasma levels of trimipramine were monitored at regular intervals, and the Zung and Millon inventories were administered at the beginning and end of each study period. Nineteen subjects completed the study. Within the trimipramine group, one reported complete disappearance of his tinnitus, eight reported improvement, three no change, and seven that tinnitus was worse. Within the placebo group, eight reported improvement, seven no change, and four that tinnitus was worse. The natural history of tinnitus is such that what has been observed may reflect the evolution of the disease itself, rather than the effect of treatment. We feel that while tricyclics may not have been shown to be effective, the placebo effect played a significant role in the results obtained.

Adult↗
PubMedDate not supplied

Hypercoagulability as a cause of sudden neurosensory hearing loss.

Fourteen patients with a documented sudden neurosensory hearing loss and four patients with other diseases causing neurosensory hearing loss were studied. The standardized coagulation workup included hematocrit, activated partial thromboplastin generation time, thrombin generation, prothrombin time, phase platelet count, platelet adhesivity, protamine sulfate, serum antithrombin III activity, fibrinogen, and Factor VIII values. Ony those patients having documented evidence of a neurosensory hearing loss occurring within hours or days were included in this study. Eight of the 14 paitents with a documented sudden neurosensory hearing loss satisfied our laboratory criteria for a diagnosis of in vitro hypercoagulability. Three of these patients had abnormal thrombin generation values, 4 had abnormal serum antithrombin III values, and 1 had an elevated platelet count. Four other patients with other diseases causing neurosensory hearing loss did not show evidence of in vitro hypercoagulability. It would appear from this data that coagulation abnormalities play a role in the pathogenesis of sudden neurosensory hearing loss.

Adult↗