Search PubMed⌕ Search

Biomedical subjects

C Snyderman

Publications and source records attributed to C Snyderman.

11 recordsLinked to original sources
PubMed2005

The role of endoscopic assisted microneurosurgery (image fusion technology) in the performance of neurosurgical procedures.

The use of endoscopic techniques has gained significant popularity over the past decade. The potential advantages of angled lenses to visualize around tight corridors without retracting have proven to be an attractive feature. The limitation of endoscopy has been the inability to obtain a true three-dimensional perspective for which microscopy is ideal. Therefore we postulated that for complex intradural lesions the merger of the two technologies would prove to be ideal. In this paper we report our experience with simultaneous microscopy and endoscopy, using picture-in-picture technology, for intracranial vascular and oncological surgery. We have found it useful to offer enough visualization to allow for performing surgery and not just for inspection.

Adult↗
PubMed2001

Complementary and alternative medicine in otolaryngology.

The widespread interest in and use of complementary and alternative medicine (CAM) by patients in the United States has been established by multiple surveys. One-third of the U.S. population uses some form of CAM, and an estimated 23 billion dollars is spent annually on these therapies. Because of prevalent usage of CAM among patients, it is important that physicians have some knowledge of this subject. With this purpose in mind, this report reviews the current research on CAM as it relates to common disorders of the head and neck: rhinitis, sinusitis, tinnitus, vertigo, and head and neck oncology.

Complementary Therapies↗
PubMed1997

Delayed resection in the management of non-orbital rhabdomyosarcoma of the head and neck in childhood.

This retrospective study was undertaken to evaluate the effect of delayed resection on outcome of head and neck rms in a single institution which has experience in cranial base surgery. Since 1988, patients with primary non-orbital rms of the head and neck following treatment at the Children's Hospital of Pittsburgh, were evaluated by the Department of Otolaryngology, Eye and Ear Hospital at the University of Pittsburgh Medical Center either at the time of presentation or when response to chemotherapy and/or radiation therapy was thought to have been optimized for the possibility of definitive surgery. Medical records of patients who did or did not have delayed surgery were reviewed and compared with respect to demographics, tumor stage, response to therapy, survival, and cosmetic results. Of 16 children diagnosed with non-orbital head and neck rms from 1988-1994 and treated with chemotherapy according to IRS II-IV, 3 had group I or II disease following extensive surgery at diagnosis. Thirteen had group III or IV disease. Of these, 6 patients had delayed resection and 7 did not. Delayed resection was undertaken 3-12 months (median, 4 months) from diagnosis in 4 children who had a partial response (PR) and 2 children who had stable disease (SD) with chemotherapy and/or radiation. Delayed resection converted all children to complete responses (CR), including one child with clinical SD and one with PR who were found to have no viable tumor at surgery. The overall percentages of CRs for patients with group III or IV disease (documented any time post-diagnosis) were at least as good for patients who had undergone delayed surgery as for those who had not (100% vs. 71%, p = .465). Median survivals for patients with advanced disease were 3 1/2 years and 2 years, respectively (p = .2801). Cosmetic and functional problems attributable to surgery were not severe but included facial asymmetry (n = 4), trismus (n = 1), cranial nerve deficits (n = 1), and abnormal dentition (n = 1). In locally extensive head and neck rms, cranial base surgery should be considered after initial cytoreductive therapy, since it may contribute to achievement of CR and to survival with acceptable morbidity.

Child↗
PubMed1993

Evidence for local and systemic activation of immune cells by peritumoral injections of interleukin 2 in patients with advanced squamous cell carcinoma of the head and neck.

Interleukin 2 (IL2) was injected peritumorally and intranodally in 36 patients with unresectable squamous cell carcinoma of the head and neck enrolled in an Eastern Cooperative Oncology Group-sponsored phase Ib trial (EST P-Z388). Groups of 6 patients received escalating doses(200, 2 x 10(3), 2 x 10(4), 2 x 10(5), 2 x 10(6), and 4 x 10(6) units) of IL2 daily 5 times/week for 2 weeks. Tumor biopsies were obtained before and after IL2 therapy. Tumor tissue was provided for histology, and the remaining fresh tissue was divided for snap-freezing in -75 degrees C and for separation of tumor-infiltrating lymphocytes (TIL) and tumor cells. Immunophenotyping of TIL performed on cryostat sections of paired pre- and post-IL2 biopsy tissues showed increases after IL2 therapy in the number of T-cells (P = 0.005), natural killer (NK; CD16+) cells (P = 0.0001), CD25+ cells (P = 0.004), and HLA-DR+ cells (P = 0.001) accumulating in the tumor stroma. In the tumor parenchyma, NK cells (P = 0.0001) and HLA-DR+ cells (P = 0.003) were increased after IL2 therapy. The T:NK cell ratios in the tumor stroma and parenchyma were decreased after therapy, suggesting selective accumulation of NK cells. By flow cytometry, TIL recovered from post-IL2 biopsy tissues were enriched (P < 0.05) in CD3-CD56+ (NK) cells. In situ hybridization with [35S] cDNA probes for cytokines and IL2 receptors indicated that the numbers of cells expressing mRNA for IL2, tumor necrosis factor alpha, IL1-beta, gamma-interferon, transforming growth factor beta, and IL2 receptor p55 or p70 were increased in post-IL2 biopsy tissues as compared to pre-IL2 tissues. Cytolytic activity of TIL isolated from post-IL2 tissues was also increased, as determined in 4-h 51Cr release assays against K562 targets (12 +/- 3 mean lytic units/10(7) cells +/- SEM pre-IL2 versus 46 +/- 13 post-IL2; n = 16) and against autologous tumor (13 +/- 8 versus 68 +/- 26; n = 9). Fresh TIL of one clinical responder showed relatively high levels (195 lytic units) of autotumor cytotoxicity after IL2 therapy versus no activity prior to therapy. In the blood, NK and lymphokine-activated killer cell activity, and percentages of CD3-CD56+ NK cells and of activated (CD25+) T-lymphocytes were increased for all doses of IL2.(ABSTRACT TRUNCATED AT 400 WORDS)

Carcinoma, Squamous Cell↗
PubMed1991

Crack cocaine burns of the larynx.

Burn injuries of the larynx are a previously unrecognized complication of cocaine abuse. The clinical presentations and magnetic resonance imaging findings of two patients are presented. Recognition of this entity is important to avoid errors in diagnosis and in management.

Adult↗
PubMed1989

Biology, cytogenetics, and sensitivity to immunological effector cells of new head and neck squamous cell carcinoma lines.

Twenty-one head and neck squamous cell carcinoma (HNSCC) cell lines were established from 89 fresh tumor specimens in order to study the biology of HNSCC lines, establish tumors in nude mice, and evaluate the sensitivity to immunological effector cells of these tumors in vitro and in vivo in nude mice. The lines were established from explants using differential trypsinization and culture for 2 to 20 mo. The explants were derived from 11 different sites. Three pairs of lines were derived from both the primary tumor and metastatic lymph nodes in the same patients. All cultures grew as either compact or diffuse adherent monolayers, and they had a median doubling time of 86 h (range, 33 to 531 h). DNA fingerprinting confirmed that the HNSCC lines were individual isolates. Thirteen of 14 lines tested induced tumors in athymic mice. The histology of each line growing in nude mice was similar to that of the original tumor tissue. Immunocytochemistry showed keratin production in all lines tested. Aneuploidy (36 to 87 chromosomes) was present in all 16 lines studied; the median chromosome number for lines derived from primary tumors was 70, whereas for lines originating from metastatic or recurrent tumors, it was 54. Karyotypic analysis showed deletion of the short arm of chromosome 3 (3p-) in 12 of 16 cell lines and trisomy 6 in 12 of 16 lines. In addition, translocations between chromosomes 9 and 11 or 9 and 12 were each present in five of 16 lines tested. The HNSCC lines were resistant to lysis by natural killer cells, but were efficiently lysed by lymphokine-activated killer cells in 4-h 51Cr release assays. These new lines have allowed us to establish a model of local adoptive immunotherapy of HNSCC in tumor-bearing nude mice, and they provide a resource for future studies of the biology of HNSCC.

Adult↗
PubMed1988

Facial paralysis: traumatic neuromas vs. facial nerve neoplasms.

Traumatic neuromas (TN) are benign proliferations of neural tissue that may occur without disruption of the facial nerve. The clinical presentation, as well as the radiographic appearance, may suggest neoplastic involvement of the facial nerve. Histologically, they may closely resemble neurilemomas (Schwannomas) or neurofibromas. Three cases of TN of the facial nerve associated with facial paralysis are presented here. Unlike previously reported cases, these tumors were not associated with chronic inflammatory middle ear disease. TN must be considered in the differential diagnosis and treatment of facial paralysis.

Adolescent↗
PubMed1986

Extraparotid Warthin's tumor.

Papillary cystadenoma lymphomatosum (Warthin's tumor) is a benign, slowly growing tumor found almost exclusively in the parotid gland or periparotid lymph nodes. Our experience with 14 cases of extraparotid Warthin's tumor (EPWT) over 22 years is presented. All cases occurred in extraparotid lymph nodes and represented 8.0% of 176 Warthin's tumors accessioned during this time. Fourteen cases of EPWT occurred in 13 patients (seven men and six women) between 41 and 77 years old. Three of the 13 patients (23%) had associated Warthin's tumor of the parotid gland. One of these patients also had a metachronous EPWT presented as a contralateral cervical mass. EPWT was discovered incidentally in six patients (46%) undergoing neck dissections for malignancies of the head and neck. Four patients (31%) presented with clinically evident solitary cervical masses. The embryologic basis for such findings is discussed. EPWT is adequately managed by conservative excision.

Adenolymphoma↗
PubMed1986

Carcinoid tumor of the larynx: case report and review of the world literature.

The clinical, light microscopic, and ultrastructural features of a carcinoid tumor occurring in the larynx of an 80-year-old man are presented and compared with 22 laryngeal carcinoids described in the world literature. These 23 tumors occurred in persons from 45 to 80 years of age (mean age was 61 years) and were three times more common in men than in women. Hoarseness was the most common presenting symptom. Sixty-one percent of the tumors were supraglottic, 26% were transglottic, 4% were glottic, 4% were subglottic, and 4% were unspecified. At least 15 (65%) of the patients are known to have developed metastases. Nine of these (60%) presented with only regional lymph node metastases, one of which was occult. Surgery is the treatment of choice, with the extent dependent on the stage of disease. Radiation therapy appears ineffective, and chemotherapy is largely untested. The 2- and 4-year determinate survival rates were 59% and 25%, respectively.

Aged↗
PubMedDate not supplied

Antibiotic prophylaxis in cranial base surgery.

The role of perioperative antibiotic prophylaxis was investigated in 95 patients undergoing 100 clean-contaminated cranial base surgeries. A variety of antibiotic regimens were employed. Potential risk factors for local infection were analyzed. Seven patients (7%) developed infections at the surgical site (meningitis, intracranial abscess, cellulitis/abscess, and osteomyelitis). Antibiotic prophylaxis for 24 hours or less was associated with a significantly increased risk of infection (p less than 0.04). Prolonged antibiotic prophylaxis (greater than 48 hours) was not more efficacious than prophylaxis for 48 hours. The surgical approach, type of reconstruction, duration of surgery, and use of drains were not significantly correlated with wound infection. The risk of intracranial infection following cranial base surgery is low despite the presence of bacterial contamination intraoperatively. Broad-spectrum coverage of gram-positive and gram-negative organisms for at least 48 hours is recommended. Attention to surgical technique is important in preventing infectious complications.

Adolescent↗