Ribosomal DNA as target for the assessment of DNA degradation of human and canine DNA.

The assessment of DNA amount and DNA integrity can support forensic DNA analysis, in particular of problematic traces such as single telogen hairs where STR typing success is often hampered by low amounts and strong degradation of nuclear DNA. Common strategies consist of quantitative polymerase chain reaction (qPCR)-based analysis of the abundance of a short versus a long nuclear amplicon, the latter prone to DNA degradation. To increase sensitivity, commercial qPCR solutions rest on amplification of multi-copy DNA sequences. Here we show that ribosomal DNA (rDNA) sequences are well suited for the same purpose. Because rDNA sequences are present in high copy number in most eukaryotic species, qPCR strategies can easily be adapted to non-human species. In this paper, we establish qPCR-based assays for human or dog DNA, respectively, which allow for sensitive analysis of DNA amounts and DNA degradation. We show that the human system can be applied to DNA of single telogen hairs, where STR typing success correlates with measured amounts and integrity of the DNA. By adapting the system to dog rDNA sequences we found that single telogen dog hairs often displayed less DNA degradation than human telogen hairs, in most cases allowing for successful STR typing. Thus, qPCR-based analysis of rDNA represents a cost-effective, highly sensitive strategy to assess DNA amount and integrity that can be adapted to hairs or other traces from various animal species.

Malignant melanoma of the head and neck: effect of treatment on survival.

This study compared outcomes for intermediate-thickness (1.5 to 3.99 mm) head and neck melanomas treated with or without elective lymph node dissection (ELND). The records of all head and neck melanomas treated at Virginia Mason Medical Center from 1974 through 1995 were reviewed and analyzed for outcome by stage and elective or therapeutic lymph node dissection. One hundred seventy-four patients with head and neck melanomas were treated in the study period, of which only 25% had intermediate-thickness lesions. Of 38 clinically node-negative patients with intermediate-thickness lesions followed more than 3 years, 10 underwent ELND, yielding two positive dissections (20%). The rate of distant metastases and the mortality rate were 44% and 35% lower in patients undergoing ELND compared with stage II patients who did not undergo ELND, but the difference did not achieve statistical significance (P = 0.12 and 0.21, respectively). The role of ELND in head and neck melanoma is uncertain. This retrospective study is limited by the small number of intermediate-thickness lesions, yet there appears to be a survival advantage to ELND in head and neck melanoma, even in negative dissections. Conventional histologic stains miss micrometastases detected by immunohistological and polymerase chain techniques. Removal of such micrometastases may explain the improved outcome. A multicenter prospective trial in head and neck melanomas, incorporating the latest techniques of sentinel node biopsy and immunohistological staining of node specimens, is needed to clarify definitive therapy for this increasingly common diagnosis.

Comparison of cost and function in reconstruction of the posterior oral cavity and oropharynx. Free vs pedicled soft tissue transfer.

OBJECTIVE: To compare the cost and functional results of free and pedicled soft tissue reconstruction after posterior oral cavity and oropharyngeal extirpation. DESIGN: Retrospective study of 53 consecutive patients undergoing extirpation with primary soft tissue reconstruction from January 1, 1991, to December 31, 1995. Median follow-up was 298 days. SETTING: Academic tertiary care medical center. INTERVENTION: Twenty-four patients underwent reconstruction with a pedicled pectoralis major myocutaneous flap (PMMF); 29 patients, with a fasciocutaneous free flap (FF) (27 radial forearm, 1 lateral arm, and 1 scapular). MAIN OUTCOME MEASURES: Direct (inpatient hospital resources used and monetary costs) and intangible (post-operative complications and function) costs. RESULTS: Operative time was longer for FF reconstructions (P = .003), but both patient groups had similar intensive care unit and hospital stays. Treatment cost for FF reconstructions was $41,122, compared with $37,160 for PMMF reconstructions (P = .003). This difference was due to increased professional fees for FF reconstruction (P < .001) which was offset by intangible cost differences. The PMMF group tended toward an increased rate of flap-related complications, compared with the FF group. At last follow-up, 4 patients in the FF group (15%) and 3 in the PMMF group (15%) had their tracheotomy. In contrast, 17 (85%) patients in the PMMF group and 11 (39%) patients in the FF group required enteral tube feedings (P = .002). Also, 18 (64%) patients in the FF group were eating at least a soft diet compared with 6 (30%) patients in the PMMF group (P = .02). CONCLUSIONS: Comparison of direct costs reveals only a modest difference in reconstruction costs that is outweighed by the intangible costs of PMMF reconstruction. The functional benefits of FF reconstruction appear to justify its slight increased expense and its use rather than PMMF reconstruction after extirpation in the posterior oral cavity and oropharynx.

Prevention of venous thrombosis in microvascular surgery by transmural release of heparin from a polyanhydride polymer.

BACKGROUND: The effects of transmurally released heparin on the patency of microvenous anastomoses were studied by using a bioerodible polymer delivery system in a rat microvascular thrombosis model. METHODS: A polyanhydride carrier with heparin was wrapped around the outside of a highly thrombogenic venous inversion graft in 14 animals, and patency rates were compared with those of 17 control animals. RESULTS: Anastomotic patency was significantly greater in the groups treated with transmurally released heparin, measured both at 24 hours (86% versus 16%; p < 0.02) and at 7 days (86% versus 36%; p < 0.05) after operation. No significant complications occurred. CONCLUSIONS: Controlled release of heparin by transmural delivery is an effective and safe form of local antithrombotic therapy and may have applications both in microvascular and large vessel surgery.

Predictors of carcinomatous invasion of the mandible.

The preoperative assessment of mandibular invasion by oral or oropharyngeal squamous cell carcinoma poses a challenge for the head and neck surgeon. A study of 64 composite resection patients was performed to determine which variables in the patient's history, physical exam, and diagnostic workup had a predictive association with carcinomatous mandibular invasion. Four postoperative variables were included in this analysis. Thirty-nine percent of the mandibular specimens demonstrated cancerous involvement. A multivariate recursive partitioning statistical analysis was performed to create a decision tree. Branching was based on the two statistically predictive variables: computed tomographic (CT) scan results and primary tumor location. The guide provides improved predictive accuracy with a 100% negative predictive value (NPV) and a 46% positive predictive value (PPV). This decision guide should help the surgeon provide accurate patient counseling, anticipate reconstructive needs, and maximize surgical oncologic effectiveness.

Microvascular reconstruction in the head and neck.

Microvascular surgery provides a new frontier in head and neck reconstruction. Restoration of form and function in patients undergoing radical surgery for head and neck malignancies is now possible to a degree that was previously unattainable using other methods of reconstruction. Massive soft tissue and bony defects can now be reconstructed in a single stage procedure with superior functional results. The investment of increased time and effort in the operating room can produce a substantial benefit for the patient.

Osteomyelitis of the skull base, etiology unknown.

OSB can occur in the absence of an obvious contiguous source of infection. When a patient has persistent unilateral headache, elevated ESR, and radiographic evidence of a lytic skull-base lesion, the clinician should consider OSB as a potential diagnosis. A baseline gallium scan should be obtained before biopsy, since surgery or trauma can also produce positive results on radionuclide scans. Technetium-phosphate bone scans should also be performed before any surgical manipulation. However, positive results from a gallium or technetium scan in this setting are not conclusive evidence of infection. At biopsy, the otolaryngologist-head and neck surgeon should consider sending a specimen to the microbiology department for culture in addition to the specimen sent for routine pathologic study; this procedure could minimize delay in diagnosis. Establishing the diagnosis in these patients without obvious contiguous infection can be difficult, demanding perseverance and an appropriate index of suspicion. Once the diagnosis is confirmed, intravenous antibiotic therapy should begin immediately. The duration of therapy must be individualized; patients may require from 4 weeks to several months of treatment. Response to therapy is indicated by resolution of symptoms, normalization of ESR, and reversal of abnormalities on radionuclide scans. Serial gallium scans are particularly useful in following response to treatment.

Prevention of microvascular thrombosis with controlled-release transmural heparin.

The use of controlled local-release heparin was studied as a means to prevent thrombosis in microvascular surgery, using a rat arterial inversion graft as a model. Polyvinyl alcohol embedded with heparin was placed around the outside of inversion graft anastomoses in 16 animals. Results were compared with control group animals in which polyvinyl alcohol alone was placed around the graft or systemic heparin was given. Vessel patency rates were significantly higher for animals receiving either systemic or transmural heparin than for animals in the control group. Controlled local delivery of heparin did not cause measurable systemic anticoagulation. However, the complication of local hematoma formation occurred as frequently as in the systemic heparin group. Controlled transmural release of heparin has an effective local antithrombotic effect and may hold promise for use in clinical practice.

Perioperative complications and risk factors in the surgical treatment of obstructive sleep apnea syndrome.

A retrospective review of 135 patients surgically treated for obstructive sleep apnea syndrome (OSAS) from 1982 to 1987 was performed to identify perioperative complications and potential risk factors. The incidence of complications was 13% (18/135). Airway problems comprised 77% (14/18) of these complications, resulting in one death. There were three postoperative hemorrhages and one postoperative arrhythmia. Comparison of the complication group versus the noncomplication group showed a statistically significant difference in the minimum oxygen saturation (66% vs. 79%) and apnea index (75 vs. 57) on the pre-operative sleep study and in the amount of narcotic administered intraoperatively. Patients with intubation complications tended to be heavier, whereas patients with extubation complications received significantly more narcotic analgesia intraoperatively. Risk for a perioperative complication was not related to age, type of obstructive symptoms, medical problems, or concurrent septoplasty/tonsillectomy. A protocol for perioperative airway management is presented.

Blood use in head and neck tumor surgery. Potential for autologous blood.

Recent increased concern regarding the risks of homologous blood transfusion led us to examine the use of blood products for head and neck tumor surgery. Major head and neck surgical procedures at three University of Washington (Seattle)-affiliated hospitals during 1987 were reviewed. Seventy-seven patients were identified. Parameters studied included the following: tumor site and stage, prior treatment, surgical procedure, preoperative and postoperative hematocrit values, estimated blood loss, operative and postoperative blood product use, and operative time. Data were grouped by procedure. Maxillectomy/midface procedures showed the highest average estimated blood loss (1037 mL) and the highest average blood use (1.5 units), followed by composite resections (883 mL and 0.8 units) and laryngectomies (724 mL and 0.9 units). When the data were subgrouped, larynogopharyngectomy (1450 mL and 4.0 units) and composite resection with mandibular swing (1300 mL and 1.0 units) showed the highest blood loss and blood product use. In the assessable groups, previous administration of radiation did not make a significant difference in blood loss or procedure time. However, blood loss correlated well with procedure time in all groups. The great majority of patients met all requirements to function as blood donors (84%). Sixty-five percent of patients met all criteria and used less than 2 units of blood, making autologous blood a reasonable option for the majority of patients with head and neck tumors.

Adenocarcinoma of the parotid.

All of the consultants considered needle biopsy an integral tool in management of a parotid neoplasm. If the tumor was limited to the superficial lobe of the parotid, they were split between ordering no further tests (Drs. Johnson and Glenn) and proceeding with a CT scan (Dr. Beckford). If frozen section revealed adenocarcinoma, the consultants agreed that a total parotidectomy with preservation of any uninvolved nerve would be in order. If the nerve had to be sacrificed, repair should be with a greater auricular or sural nerve graft. Two consultants (Drs. Beckford and Glenn) would search for a distant primary or metastasis. Controversy regarding management of an N0 neck divided the group into favoring neck dissection (Drs. Beckford and Johnson) and a modified radical neck dissection (Dr. Glenn). In the case of anaplastic carcinoma the consultants differed by suggesting an extended resection (Dr. Beckford), total parotidectomy with nerve preservation (Dr. Johnson), and total parotidectomy with modified radical neck dissection (Dr. Glenn). All the consultants recommended postoperative radiotherapy.

Surgical treatment of the "marginal mandibular lip" deformity.

Unilateral permanent paralysis of the lower lip after section or compression of the marginal mandibular branch of the facial nerve is not rare. It may occur after trauma or as a result of parotid, ear, or upper neck surgery. Surgical treatment of the deformity--which we term the marginal mandibular lip--is indicated to improve cosmesis and restore oral competence during eating and speech. We describe our experience with partial resection of the paralyzed lower lip as an effective yet simple method of surgical correction. We also review the alternate methods of treatment for comparison.

Treatment of cervical esophageal stenosis with a long-term indwelling prosthesis.

Intubation of the cervical esophagus with a long-term indwelling prosthesis is described to palliate malignant strictures, and manage benign strictures in high-risk patients. The inner cannula of a Moore design tracheostomy tube was used as the prosthesis. Over a 10-year period, seven cases were managed in this fashion. The tube remained in place in five of seven patients for periods of 1.5 to 11 months, while a pureed or well-masticated soft diet was tolerated. There were no major complications in this small series. Retrograde displacement was the most common minor complication; displacement did not occur in the last two cases after addition of a silicone sponge ring to the distal end of the prosthesis. Pain and discomfort was experienced in two cases, requiring temporary removal in one patient.

Threshold concentration of ozone causing an increase in bronchial reactivity in humans and adaptation with repeated exposures.

To determine the lowest concentration of ozone that causes an increase in bronchial reactivity to histamine and to determine whether adaptation to this effect of ozone develops with repeated exposures, we studied 19 healthy adult subjects. Bronchial reactivity was assessed by measuring the rise in specific airway resistance (delta SRaw) produced by inhalation of 10 breaths of histamine aerosol (1.6% solution). In 5 subjects, bronchial reactivity was determined at 9:00 and 11:30 A.M. on 4 consecutive days without exposure to ozone (Group I). In 7 other subjects (Group II), bronchial reactivity was assessed at 9:00 and 11:30 A.M. on 3 consecutive days, and subjects were exposed to 0.2 ppm of ozone from 9:30 to 11:30 A.M. on the third day. Seven additional subjects (Group III) had bronchial reactivity assessed in a similar fashion for 2 days and then again on 3 consecutive days of 2-h exposures to 0.4 ppm of ozone. Pre-exposure bronchial reactivity of the groups was the same, and no change in bronchial reactivity occurred in the group tested repeatedly but not exposed to ozone. An increase in delta SRaw provoked by histamine was noted after the first exposure to 0.4 ppm but not to 0.2 ppm of ozone (p less than 0.025). With 3 repeated 2-h exposures to 0.4 ppm on consecutive days, however, the delta SRaw produced by histamine progressively decreased, returning to pre-exposure values after the third exposure. Our results indicate that the threshold concentration of ozone causing an increase in bronchial reactivity in healthy human subjects is between 0.2 and 0.4 ppm, and that adaptation to this effect of ozone develops with repeated exposures. The threshold concentration of ozone identified in other studies as causing changes in symptoms, lung volumes, or airway resistance was also between 0.2 and 0.4 ppm, and the time course of the development of tolerance to ozone in these other studies was similar to hat observed in our study. We propose that the appearance of symptoms, changes in pulmonary function, and the increase in bronchial reactivity may be caused by a change in the activity of afferent nerve endings in the airway epithelium.