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Biomedical subjects

R J Schlosser

Publications and source records attributed to R J Schlosser.

16 recordsLinked to original sources
PubMed2005

Endoscopic repair of frontal sinus cerebrospinal fluid leaks.

OBJECTIVE: To describe endoscopic management of frontal sinus cerebrospinal fluid (CSF) leaks. STUDY DESIGN: Retrospective. METHODS: We reviewed all frontal sinus CSF leaks treated using an endoscopic approach at our institutions from 1998 to 2003. CSF leaks originated immediately adjacent to or within the frontal recess or frontal sinus proper for inclusion in the study. Data collected included demographics, presenting signs and symptoms, site and size of skull-base defect, surgical approach, repair technique, and clinical follow up. RESULTS: Seven frontal sinus CSF leaks in six patients were repaired endoscopically. Average age of presentation was 45 years (range 25-65 years). Aetiology was idiopathic (three), congenital (one), accidental trauma (one), and surgical trauma (two). All patients presented with CSF rhinorrhea; two patients presented with meningitis. Four defects originated in the frontal recess, while two others involved the posterior table and frontal sinus outflow tract. Four patients had associated encephaloceles. We performed endoscopic repair in all six patients with one patient requiring an adjuvant osteoplastic flap without obliteration. All repairs were successful at the first attempt with a mean follow up of 13 months. All frontal sinuses remained patent on both post-operative endoscopic and radiographic exam. CONCLUSIONS: Endoscopic repair of frontal sinus CSF leaks and encephaloceles can be an effective method if meticulous attention is directed toward preservation of the frontal sinus outflow tract, thus avoiding an osteoplastic flap and obliteration. The major limiting factor for an endoscopic approach is extreme extension superiorly or laterally within the posterior table beyond the reach of current instrumentation.

Adult↗
PubMed2001

Aggressive endoscopic resection of inverted papilloma: an update.

OBJECTIVE: Endoscopic resection has been proposed for sinonasal inverted papilloma (IP). Our objective was to determine the efficacy of aggressive endoscopic resection of IP. METHODS: Retrospective analysis was performed on patients undergoing endoscopic resection of IP at the University of Virginia between 1990 and 1996. Total ethmoidectomies, wide maxillary antrostomies, frontal recess explorations, sphenoidotomies, and turbinate resection were performed as required. Once all visible papilloma was removed, residual mucosa was removed by using a diamond burr to polish bone at the site of origin. RESULTS: Twenty-one patients were treated with endoscopic resection of IP. Only 1 of 21 patients had an adjunctive external procedure (an osteoplastic flap without obliteration). Average follow-up was 41.9 months after initial aggressive endoscopic resection at the ureterovesical angle. Recurrences occurred in 19% (4/21) of patients. One of the 4 had two recurrences. Recurrences occurred in 16 months or less, except for one noted at 35 months and another at 56 months. CONCLUSIONS: Aggressive endoscopic resection of IP by experienced rhinologists is an acceptable treatment.

Adolescent↗
PubMed2001

Autologous fibrin sealant reduces pain after tonsillectomy.

OBJECTIVES/HYPOTHESIS: Pain is a major cause of morbidity after tonsillectomy. Although various efforts have been made to reduce pain, the use of oral analgesics, which can have adverse side effects, remains the standard of care. It is hypothesized that fibrin sealant, used to achieve hemostasis and enhance healing in many surgical procedures, might help decrease pain after this operation. STUDY DESIGN: A prospective, randomized, blinded study was performed on 20 children aged 5 to 17 years who were undergoing tonsillectomy, to evaluate the efficacy of FIBRIN SEALANT in reducing postoperative pain. METHODS: All patients pre-donated 40 mL of blood from which autologous concentrated fibrinogen was prepared by cryoprecipitation. In the fibrin sealant group, fibrinogen and topical bovine thrombin were sprayed onto the surgical site to form fibrin sealant at the conclusion of tonsillectomy. The 10 patients in the control group (C) received no fibrin sealant. Patients rated their level of pain immediately after surgery and at regular intervals for 3 days after surgery using the Wong-Baker Faces Pain Rating Scale (1-6). Emesis, postoperative bleeding, medications, and adverse events were also evaluated. RESULTS: At 7.00 P.M. on postoperative day (POD) 0, the mean +/- SD fibrin sealant group pain score (2.9+/-0.41 units) was significantly lower than for the C group (4.1+/-0.43 units; P < or = .05). There was also a trend in favor of less pain in the fibrin sealant group at 7:00 P.M. on POD 1, with a mean of 3.5+/-0.43 units versus 2.4+/-0.48 units for C (P = .15). The odds of a patient in C experiencing emesis were 8.16 times higher, (P < or = .05) than for patients in the fibrin sealant group. CONCLUSIONS: Fibrin sealant significantly reduced pain the evening after pediatric tonsillectomy and also decreased the chance of experiencing emesis. Thus fibrin sealant may be clinically useful as an adjunct to tonsillectomy.

Administration, Topical↗
PubMed2001

Microbiology of chronic frontal sinusitis.

OBJECTIVES: To determine bacterial and fungal organisms that are present in patients undergoing surgery for chronic frontal sinusitis. STUDY DESIGN: Retrospective, nonrandomized study. METHODS: Retrospective, nonrandomized bacterial and fungal cultures were performed on 46 sinus aspirates obtained by frontal sinus trephination performed on 30 consecutive patients with chronic frontal sinusitis. RESULTS: Six patients were having sinus surgery for the first time, 19 patients had undergone prior functional endoscopic sinus surgery without instrumentation of the frontal sinus/recess, and the third group included 5 patients who had undergone prior frontal sinus/recess surgery. Preoperative computed tomography scan of the frontal sinuses revealed complete opacification in 63% (29/46 frontal sinuses) and partial opacification in 22% (10/46), and no data were available for 15% (7/46). Aerobic cultures revealed that 38% (13/35 cultures) had no growth, 21% (7/35) grew Staphylococcus aureus, 21% (7/35) grew coagulase-negative Staphylococcus, 9% (3/35) grew Haemophilus influenzae, and 26% (9/35) grew a variety of other organisms. Anaerobic cultures were positive in 3% (1/32) of sinuses, and fungal cultures were positive in 4% (1/24). Haemophilus influenzae was most common in primary cases, whereas coagulase-negative Staphylococcus was most common in patients undergoing revision frontal sinus surgery. There were no other significant differences between cultures from patients undergoing revision frontal sinus surgery, revision functional endoscopic sinus surgery without prior frontal surgery, and primary surgery. CONCLUSIONS: This study suggests that organisms involved in chronic inflammatory disease of the frontal sinus may change after previous sinus surgery. The study failed to support a significant role for anaerobes. The role for coagulase-negative Staphylococcus as a potential pathogen or a contaminating agent remains unclear.

Adult↗
PubMed2000

Elevated nitric oxide metabolite levels in chronic sinusitis.

Decreased exhaled nitric oxide (NO) is found in chronic sinusitis. NO metabolites (nitrates, nitrites, and S-nitrosothiols) were measured in sinus lavages with a rabbit model of chronic sinusitis. NO metabolite levels (mean +/- SD) were 3.0+/-1.6 micromol/L in uninfected rabbits, 10.7+/-11.4 micromol/L in infected animals, and 7.6+/-5.4 micromol/L in postantrostomy recovering animals. Infected sinuses had elevated levels of NO metabolites that were statistically significant (P<0.01) when compared with uninfected sinuses. Mucociliary transport velocity was measured in uninfected (16.0+/-5.7 mm/minute), infected (5.2+/-1.3 mm/minute), and recovery phases (3.0 mm/minute). Endoscopic appearance, light and electron microscopy, and bacterial cultures improved during recovery. Elevated levels of NO metabolites were found during chronic sinusitis and began to return to normal levels during recovery. The possible link between NO in epithelial autotoxicity and host defense mechanisms warrants further investigation.

Animals↗
PubMed1999

Functional nasal surgery.

Functional nasal surgery is designed to repair nasal obstruction frequently caused by previous reduction rhinoplasty or blunt nasal trauma. Distinguishing the statically narrowed nasal valve from the weak sidewall with dynamic collapse is an important part of the preoperative evaluation. Our workhorse for repair of static obstruction is the combination of spreader grafts and flaring sutures, which together create a significant increase in the intranasal valve area. Dynamic collapse of the sidewall is corrected with cartilaginous batten grafts designed to increase sidewall rigidity. Less common causes of valve obstruction, such as tip ptosis, facial paralysis, cicatricial stenosis, Mohs reconstruction, and paradoxical lateral crura, are repaired by more individualized techniques.

Cartilage↗
PubMed1997

Signal transduction pathways in modulation of ciliary beat frequency by methacholine.

The release of endogenous neurotransmitters plays an important role in the airway mucosal defense system. We studied the in vitro effect of methacholine, a beta-methyl ester of acetylcholine, on the ciliary beat frequency (CBF) of human adenoid explants and its mechanism of action. Tissue explants were cultured at 35 degrees C and covered with 1.0 mL of culture medium: minimum essential Eagle's medium (MEM) containing L-arginine (1.2 x 10(-3) mol/L). Methacholine was added to the cultured tissue at concentrations of 10(-10), 10(-8), and 10(-6) mol/L. The CBF was determined by phase contrast microscopy and microphotometry. Methacholine increased CBF in a dose-dependent manner with a maximum increase of 23.0% +/- 1.8% (p < .001). Atropine (10(-6) mol/L) significantly inhibited the ciliostimulatory effects of methacholine (p < .0007). The role of endogenous prostaglandins in methacholine-induced ciliostimulation was determined by treating specimens with a cyclooxygenase inhibitor (diclofenac sodium). Diclofenac (10(-6) mol/L) significantly inhibited the ciliostimulatory effects of methacholine (p < .0007). To determine if nitric oxide (NO) acts as an intermediary in ciliostimulation by methacholine, endogenous NO production was inhibited by treating specimens with an L-arginine analog, NG-nitro-L-arginine methyl ester (L-NAME), prior to addition of methacholine. L-NAME (10(-6) mol/L) inhibited the effects of methacholine in L-arginine-free MEM (p < .008), and this inhibition was reversed by L-arginine (10(-3) mol/L). To further examine the actions of NO in methacholine-induced ciliostimulation, a cyclic guanosine 3'5'-monophosphate (cGMP) kinase inhibitor (KT-5823) was used, prior to the addition of methacholine. KT-5823 (10(-6) mol/L) significantly inhibited the effects of methacholine (p < .0001). Ciliostimulation by methacholine in human upper airway mucosa involves both prostaglandin and NO second messengers and activation of a cGMP-dependent kinase.

Acetylcholine↗
PubMed1996

Dual signal transduction mechanisms modulate ciliary beat frequency in upper airway epithelium.

This study investigated the effects of methacholine and terbutaline on the ciliary beat frequency (CBF) of upper airway epithelium. The CBF of cultured human adenoid explants was measured using microphotometry. Methacholine (10(-6) M) and terbutaline (10(-6)M) increased CBF a maximum of 23.0 +/- 1.8% (P < 0.001) and 16.5 +/- 2.3% (P < 0.001). Inhibition of endogenous nitric oxide (NO) production by nitro-L-arginine methyl ester (L-NAME) (10(-6) M) abolished the effects of methacholine in L-arginine-free medium (P < 0.008). This inhibition was reversed by addition of L-arginine. There was no inhibition of terbutaline-induced ciliostimulation by L-NAME (P < 0.5). KT-5823 (10(-6)M), a guanosine 3',5'-cyclic monophosphate (cGMP) kinase inhibitor, significantly inhibited the effects of methacholine (P < 0.0001), but not terbutaline (P > 0.15). H-89 (10(-6) M), a cAMP kinase inhibitor, significantly inhibited terbutaline-induced ciliostimulation (P < 0.0001), but not methacholine-induced ciliostimulation (P > 0.05). Diclofenac (10(-6) M), a cyclooxygenase inhibitor, significantly inhibited the effects of methacholine (P < 0.0007) but had no effect on terbutaline-induced ciliostimulation (P > 0.05). These findings suggest that the CBF of upper airway epithelium is modulated through at least two distinct pathways. The beta 2-adrenoceptor produces ciliary stimulation by a pathway involving increased intracellular cAMP levels, while the muscarinic receptor increases CBF by a mechanism involving production of prostaglandins, NO, and cGMP.

Adenoids↗
PubMed1995

Signal transduction mechanisms in substance P-mediated ciliostimulation.

Substance P is a neuropeptide released by afferent neurons in the respiratory tract during inflammatory reactions. It produces effects on blood vessels, bronchial smooth muscle, nasal glands, and respiratory cilia. We studied the in vitro effect of substance P on the ciliary beat frequency of human adenoid explants and its mechanism of action. Substance P was added to cultured adenoid at concentrations of 10(-10), 10(-8), 10(-6), and 10(-4) mol/L. Ciliary beat frequency was determined with phase-contrast microscopy and microphotometry. Substance P increased ciliary beat frequency a maximum of 11.9% +/- 3.8% (p < 0.01). Diclofenac (10(-6) mol/L) significantly blocked the ciliostimulatory effects of SP (p < 0.022), indicating that prostaglandin synthesis is an intermediate step in the action of substance P on ciliary beat frequency. The L-arginine analogs, NG-nitro-L-arginine methyl ester and NG-monomethyl-L-arginine, inhibit nitric oxide synthesis from L-arginine. L-Arginine analogs (10(-4) to 10(-2) mol/L) inhibited the effect of substance P (p < 0.02 at the higher concentration). This inhibition was reversed by adding L-arginine, demonstrating that nitric oxide production is a required step in substance P-induced ciliostimulation. Substance P stimulates ciliary activity in human nasal mucosa as a result of secondary production and release of endogenous prostaglandins and nitric oxide. It is likely that inflammatory disease processes that stimulate release of substance P and subsequent prostaglandin and nitric oxide production modify mucociliary transport. Pharmacologic modification of substance P and its second messengers may eventually permit regulation of this important defense mechanism and control of neurogenic inflammation.

Adenoids↗
PubMed1979

Cost containment via expense rationalization in open-heart surgery.

Hospital costs and the fees of the surgeon, assistant, anesthesiologist, and cardiologist were reviewed in a community hospital doing 425 cardiac operations in the year 1977. Each item of the bill was analyzed and discussed with each department of the hospital. Changes made in the routine saved approximately $1000 per patient--16% for patients having mitral valves replacement (MVR), 15% for those having aortic valve replacement (AVR), 21% for those having saphenous vein bypass grafts (SVBG), and 23% for pediatric cases. The areas most likely to yield economic reductions without alteration of the quality of care are operating room, patient room, respiratory therapy, and pharmacy. Making the nurses, scrub technicians, surgical assistants, residents, and staff surgeons aware of the cost of each item and periodically discussing the alternatives could yield surprisingly large savings.

Adult↗
PubMed1975

Aneurysm of saphenous vein bypass graft to coronary artery.

A few cases of aneurysmal dilatation of autogenous vein grafts to peripheral arteries have been reported. However, to our knowledge, no case of this complication in coronary artery vein bypass grafts have been found. We are presenting a case of a vein graft aneurysm which appeared 6 months postoperatively. The patient had had an aortic valve replacement and a vein bypass graft to the right coronary artery.

Adult↗
PubMedDate not supplied

Surgery for the dysfunctional nasal valve. Cadaveric analysis and clinical outcomes.

OBJECTIVES: To quantify changes in the cross-sectional area of the nasal valve after placement of spreader grafts and flaring sutures and to review clinical outcomes after nasal valve surgery. DESIGN: The minimal cross-sectional area of cadaveric nasal valves was measured after placement of spreader grafts and flaring sutures. Clinical outcomes for patients undergoing functional rhinoplasty were retrospectively reviewed. SETTING: Academic medical center. SUBJECTS: Six fresh cadaver heads and a review of patients from September 1994 through May 1998. INTERVENTION: Acoustic rhinometry was performed after placement of spreader grafts, flaring sutures, and the two together. Clinically, a site-specific repair was performed with spreader grafts and flaring sutures for statically narrowed internal nasal valves and cartilaginous battens for dynamic collapse. MAIN OUTCOME MEASURE: Cross-sectional areas of cadaveric valves. Functional and aesthetic results were determined by nasal patency scores from 1 (complete obstruction) to 10 (complete patency) and a rating of postsurgical cosmetic changes. RESULTS: Spreader grafts improved the cadaveric minimal cross-sectional areas by 5.4% (P > .05), flaring sutures by 9.1% (P > .05), and spreader grafts combined with flaring sutures by 18.7% (P < .05). Mean nasal patency scores improved from 3.4 to 6.5 (P < .01) with the combination of spreader grafts and flaring sutures. Cartilaginous battens improved scores from 2.7 to 6.3 (P < .01). CONCLUSIONS: The combination of flaring sutures and spreader grafts has the greatest impact on the cadaveric nasal airway. Either technique alone failed to have a statistically significant impact on the minimal cross-sectional area of the nasal valve. Clinical review confirms significant improvement in nasal function using this combination technique.

Acoustics↗
PubMedDate not supplied

Effects of fibrin sealant-containing antibiotics in a rabbit model of chronic sinusitis.

Postoperative complications of sinus surgery include bleeding, infection, and synechiae. Improved subjective outcomes in humans treated with fibrin sealant (FS) after endoscopic sinus surgery (ESS) have been reported. Streptococcus pneumoniae was used to initiate chronic sinusitis in occluded rabbit sinuses in order to evaluate the role of FS in mucosal healing. Six weeks later, all animals had maxillary antrostomies. Homologous FS-containing ciprofloxicin (100 mg/mL) and clindamycin (15 mg/mL) was applied topically to treatment rabbits (n = 9). Control rabbits (n = 10) received no antibiotics. Two weeks into the recovery phase after antrostomies, all animals were re-examined. Mucociliary transport velocity (mean +/- standard deviation in mm/minute) was measured in all sinuses (n = 38) during healthy (100% measurable, 13.82 +/- 4.16), infected (18% measurable, 4.74 +/- 0.42), and recovery phases (5% measurable, 6.30 +/- 4.67). In both groups, mucopurulent discharge was present in the majority of sinuses (control group 18/20, FS group 16/18). In addition, there was no significant difference in the recovery phase between the two groups when comparing changes in the size of antrostomies, light microscopy, or culture clearance. Scanning electron microscopy did suggest a possible improvement in ciliary regeneration in the FS group. Application of FS-containing antibiotics did not appear to improve healing after ESS in our rabbit model of chronic sinusitis.

Animals↗