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Biomedical subjects

A J Torsiglieri

Publications and source records attributed to A J Torsiglieri.

10 recordsLinked to original sources
PubMed1993

The growth of hearing loss in neonatal chicks exposed to intense pure tones.

One-day-old chicks were exposed to an intense pure tone (0.9 kHz, 120 dB SPL) and assigned to one of eight groups based on continuous exposure durations from 1 to 200 h. As each animal was removed from the exposure, it was anesthetized and an electrode was placed in the nucleus magnocellularis. Sound-evoked potentials were used to measure absolute thresholds and frequency selectivity. Thresholds were measured at 10 frequencies between 0.1 and 4.5 kHz while frequency selectivity was assessed by a simultaneous masking tuning-curve procedure at five probe-tone frequencies between 0.3 and 2.5 kHz. Threshold shift was greatest at 1.3 kHz and reached a maximum loss of approximately 57 dB between 48 and 200 h of exposure. The shape of the threshold-shift curve as a function of exposure duration (for frequencies between 0.9 and 2.5 KHz) suggested the presence of an early and late effect. The loss in tuning sharpness was evaluated by comparing the values of Q10 dB for control and exposed tuning curves and expressing the difference between them as a percent change. Probe-tone tuning curves above 0.9 kHz became less selective as exposure duration increased. A maximum decrease in tuning of about 54 percent was reached by 48 h and this remained constant to 200 h. The low-frequency tuning curves (below 0.9 kHz) did not show any systematic loss in selectivity. The changes in sensitivity and selectivity are discussed in relation to the patterns of cochlear injury that occurred on the basilar papilla as exposure duration lengthened.

Acoustic Stimulation↗
PubMed1991

Granular cell tumors of the head and neck in children: the experience at the Children's Hospital of Philadelphia.

Granular cell tumors are rare, usually benign tumors of controversial histogenesis. These tumors are uncommon in children. Granular cell tumors in adults have a predilection for the head and neck, but this was not noted in our experience with children. Of the 22 granular cell tumors diagnosed and managed at the Children's Hospital of Philadelphia from 1960 to 1988, 7 were from the head and neck. One child with a subglottic granular cell tumor is of particular interest and is presented in detail.

Adolescent↗
PubMed1991

First branchial cleft anomalies involving the tympanic membrane and middle ear.

First branchial cleft anomalies may involve the tympanic membrane or middle ear. A complete otologic examination must be performed in any patient with a suspected first branchial cleft anomaly. A surgeon treating such a defect must be prepared to perform both the excision of the lesion and reconstructive otologic surgery.

Branchial Region↗
PubMed1990

Branchial cleft anomalies: a five-year retrospective review.

Branchial cleft cysts, sinuses and fistulas are among the most commonly encountered congenital anomalies in pediatric otolaryngic practice. They can present difficulties in differential diagnosis and surgical management. In order to study the clinical presentation and surgical management of branchial cleft anomalies, the operative records of the Children's Hospital of Philadelphia (CHOP) were reviewed for a five year period, January 1, 1982 through December 31, 1986. All patients with a pathologically-confirmed post-operative diagnosis of a branchial cleft anomaly were included in a retrospective chart review. Their case histories were studied to determine symptoms upon presentation, presence or absence of drainage, type of lesion, site of lesion, characteristics of the lesion, accuracy of pre-operative diagnosis, recurrence and complications. A total of 71 patients, 39 males and 32 females, underwent surgical excision of a branchial cleft cyst, sinus or fistula during the study period. There were 23 branchial cleft cysts, 50 sinuses and 3 fistulas. A correct pre-operative diagnosis was established in 60 (85%) of the patients, being highest for patients with branchial cleft fistulas. Incorrect pre-operative diagnoses included thyroglossal duct cyst, cervical lymphadenitis, dermoid, dermal inclusion cyst, lymphangioma and malignant neoplasm. The clinical presentation, pre-operative evaluation, pitfalls in diagnosis, surgical management and post-operative complications are discussed and strategies for the management of branchial cleft anomalies are presented.

Branchial Region↗
PubMed1989

Approach to the pediatric neck mass.

Neck masses are frequent findings in the pediatric population and the physician caring for a child with a neck mass may be faced with a diagnostic dilemma. The etiology of pediatric cervical masses includes a variety of conditions. Unlike for the adult, there are few established guidelines for evaluation of these children. A recent review of 445 neck masses operated on at the Children's Hospital of Philadelphia noted the preoperative diagnosis to be correct in 270, or only 61%. Clinical characteristics which may aid in establishing a correct preoperative diagnosis, as well as guidelines for the evaluation of the child presenting with a neck mass will be discussed.

Biopsy↗
PubMed1988

Pediatric neck masses: guidelines for evaluation.

Neck masses are frequent findings in the pediatric population. Unlike the adult, there are few established guidelines for evaluation of these children. The etiology of cervical masses includes many conditions. Knowledge of these conditions and their clinical presentations is essential. To elucidate the clinical characteristics which may help in establishing a correct diagnosis, the charts of 445 patients with biopsies of neck masses performed at the Children's Hospital of Philadelphia were analyzed. There were 244 (55%) congenital lesions, 118 (27%) inflammatory lesions, 23 (5%) non-inflammatory benign masses, 12 (3%) benign neoplasms, and 48 (11%) malignancies. The preoperative diagnosis was correct in 270 (61%) patients. Guidelines are established for the evaluation of the child presenting with a neck mass.

Adolescent↗
PubMed1987

Biochemical characterization of autologous fibrinogen adhesive.

Fibrinogen-based adhesive, derived from pooled human plasma, has been used in Europe with great success in otologic surgery, but has not been approved for use in the U.S. because of the risk of transmitting hepatitis. Autologous fibrinogen, derived by polyethylene glycol precipitation from the blood of an individual patient would avoid this risk, and has been shown to be relatively safe to the ear in animal studies. A study of the biochemical composition of this autologous fibrinogen concentrate derived from 15 human volunteer donors was performed. The mean starting plasma fibrinogen was 2.12 mg/ml (range 1.59-3.22 mg/ml). When 10% polyethylene glycol was used to precipitate the fibrinogen, the concentrate contained, on the average, 31.8 mg of fibrinogen/ml. The percent yield averaged 54.9%, and the protein in the final product was 91.9% fibrinogen. Increasing the polyethylene glycol concentration in the precipitation process to as high as 15% resulted in an increased yield as high as 91%, but the protein in the final product was only 42.5% fibrinogen. Polyacrylamide gel electrophoresis confirmed that the predominant protein in the 10% polyethylene glycol precipitate was fibrinogen. These data suggest that highly concentrated fibrinogen can be derived with relative ease from single donor human plasma, and that the product is relatively pure. When combined with thrombin and calcium chloride, this concentrate should provide an adhesive that avoids the risks associated with fibrinogen adhesive derived from pooled blood.

Aprotinin↗