The value of ultrasound with ultrasound-guided fine-needle aspiration biopsy compared to computed tomography in the detection of regional metastases in the clinically negative neck.

PURPOSE: Head and neck oncologists have not reached consensus regarding the role of contemporary imaging techniques in the evaluation of the clinically negative neck in patients with head and neck squamous cell carcinoma (HNSCC). The purpose of the present study was to compare the accuracy of ultrasound with guided fine-needle aspiration biopsy (UGFNAB) and computed tomography (CT) in detecting lymph node metastasis in the clinically negative neck. METHODS AND MATERIALS: Sixty-four neck sides of patients with HNSCC were examined preoperatively by ultrasound/UGFNAB and CT at one of five participating tertiary care medical centers. The findings were correlated with the results of histopathologic examination of the neck specimen. RESULTS: Ultrasound with guided fine-needle aspiration biopsy was characterized by a sensitivity of 48%, specificity of 100%, and overall accuracy of 79%. Three cases had nondiagnostic aspirations using UGFNAB and were excluded. CT demonstrated a sensitivity of 54%, specificity of 92%, and overall accuracy of 77%. UGFNAB detected two additional metastases not visualized on CT, whereas CT detected no metastases not seen on UGFNAB. The results of UGFNAB were similar between the participating centers. CONCLUSIONS: Approximately one half of the clinically occult nodal metastases in our patient group were identified by both CT and UGFNAB. Overall, UGFNAB and CT demonstrated comparable accuracy. The sensitivity of CT was slightly better than UGFNAB, but the latter remained characterized by a superior specificity. The results of CT and UGFNAB did not appear to be supplementary. The choice of imaging modality for staging of the clinically negative neck depends on tumor site, T-stage, and experience and preference of the head and neck oncologist. If CT is required for staging of the primary tumor, additional staging of the neck by UGFNAB does not provide significant additional value.

Synaptic enhancement induced by NMDA and Qp receptors and presynaptic activity.

Activity-dependent changes in synaptic efficacy may underlie the acquisition of memory. Much interest has centred on the involvement of NMDA (N-methyl-D-aspartate) receptors in the induction of long-term potentiation (LTP), but since activation of this receptor alone results only in short-term enhancement, other receptors are clearly involved. This paper describes a novel form of lasting synaptic enhancement requiring concomitant activation of both NMDA and metabotropic quisqualate, or Qp receptors for induction. Neither high frequency presynaptic activity, co-activation of many presynaptic axons, postsynaptic depolarization, nor blockade of inhibition were required. However, repetitive, though relatively low frequency activity of the presynaptic axon appeared to be necessary. We suggest, tentatively, that presynaptic activity may be directly involved in priming the recently active terminal to respond to postsynaptic changes.

Predictive factors for functional recovery after free tissue transfer oromandibular reconstruction.

BACKGROUND: Recovery of upper aerodigestive tract function after reconstruction of segmental oromandiblectomy defects is frequently incomplete. The purpose of this study was to quantitate postreconstruction function and define variables that predict functional outcome in this population. METHODS: A prospective study of 21 patients who underwent microvascular free tissue transfer reconstruction of segmental oromandibular defects was performed. Measures of swallowing, speech, bite, and oral intake were performed preoperatively and at 1, 3, 6, and 12 months postoperatively or until plateau. Preoperative versus maximal postoperative measures were compared and correlated with nine potentially predictive variables. Univariate and multivariate analyses were performed to determine the most significant predictive factors. RESULTS: Baseline function in the study population was abnormal. Postoperative bite force improved, but swallowing, speech, and oral intake were worse than preoperative. Significant (univariate) predictors of outcome included diagnosis of cancer, tongue resection, pharynx resection, and flap skin paddle area. Only tongue resection remained significant in multivariate analysis. CONCLUSIONS: Increasing need for oropharyngeal lining replacement, especially after tongue resection, is the most important predictor of functional outcome in reconstruction of segmental mandible defects.

Organization of the facial nerve nucleus in the cat.

The location of efferent neurons in the brain stem of newborn kittens supplying the facial muscles was studied by means of horseradish peroxidase (HRP) used as a tracer of retrograde protein transport. Three to 15 microliters containing 0.3 to 1.5 mg of HRP was injected into the orbicularis oris and orbicularis oculi muscles of six kittens and in the seventh kitten, the ventral ramus of the facial nerve was transected and HRP was instilled on the cut end of the nerve. After a survival time of 24 hours, the animals were anesthetized, perfused by intracardic perfusion technique, and then they were fixed and the brain stems sectioned. Stains for peroxidase demonstrated the labelled neurons in the lateral division of facial nuclei in the ipsilateral side. The orbicularis oculi muscles were represented in the rostral pole of the lateral division of the facial nucleus dorsally while the orbicularis oris muscles were represented in the caudal pole of the lateral division of the facial nucleus ventrally. No labelled neurons were found in the nuclei of the Vth or any other brain stem nuclei. According to my knowledge, this method of localizing the neurons supplying the facial muscles has not been reported previously.

Facial nerve nucleus in the cat. Further study.

The location of efferent neurons, supplying muscles innervated by facial nerve, was studied in the brain stem of the cat using horseradish peroxidase. One to four microliters of HRP was injected in the frontalis, posterior belly of digastric, platysma, and auricularis superior muscles of the kittens. Their representative locations were determined in the facial nucleus. No direct relation between the amount of HRP injected and the numer of labeled neurons was found. The number of positive cells was between 2 and 661. No labeled neurons were found in nucleus of Vth or any other brain stem nuclei.

Zenker's diverticulum: analysis of surgical complications from diverticulectomy and cricopharyngeal myotomy.

OBJECTIVE: To identify risk factors for postoperative complications in patients undergoing diverticulectomy and cricopharyngeal (CP) myotomy for Zenker's diverticulum. STUDY DESIGN: Retrospective. MATERIALS AND METHODS: A chart review was conducted of all patients with a Zenker's diverticulum who were treated with diverticulectomy and cricopharyngeal myotomy at three tertiary care centers in central Indiana between 1988 and 1998. RESULTS: Of the 24 patients identified, 9 developed postoperative complications (2 medical and 7 surgical). Statistical analysis of multiple potential risk factors revealed that only diverticulum size greater than 10 cm2 at surgery placed the patient at increased risk for postoperative surgical complications. To our knowledge, this is the first report that has specifically addressed diverticulum size as an independent risk factor for postoperative surgical complications following diverticulectomy and CP myotomy. CONCLUSIONS: Given our findings, we recommend considering diverticulopexy rather than diverticulectomy in a patient with a Zenker's diverticulum greater than 10 cm2 in size if a cervical approach is the selected treatment.

Radiologic percutaneous gastrostomy: results in 56 patients with head and neck cancer.

OBJECTIVE: The establishment of a direct enteral feeding route is critical in the overall treatment of many patients with head and neck cancer. Use of radiologic percutaneous gastrostomy (RPG), the newest technique for gaining enteral access, has not been studied in such patients extensively. This study evaluated the indications, technique, success rate, and complications associated with RPG in patients with head and neck cancer. STUDY DESIGN: Retrospective. METHODS: A comprehensive chart review was undertaken of 56 patients with head and neck cancer treated at a tertiary care institution who had undergone successful or attempted RPG at some point during their treatment course. RESULTS: Most study patients had advanced oropharyngeal squamous cell carcinoma. The most frequent indications for RPG were dysphagia/aspiration following tumor resection (n = 26) and dysphagia following completion of single- or combined-modality therapy (n = 22). The success rate of attempted RPGs was 98.2%. The overall complication rate for RPG was 12.7% (10.9% minor and 1.8% major). CONCLUSIONS: RPG is a valuable tool for establishing enteral nutrition in patients with head and neck cancer. Advantages of RPG include high success rate despite obstructing lesions, low complication rate, time efficiency and scheduling ease compared with intraoperative percutaneous gastrostomy (PEG) by a second team, no reported tumor seeding of the tube site, and the fact that postoperative RPG allows for more accurate selection of patients who require a gastrostomy tube.

Anatomic organization of the cat facial nerve.

The location of efferent neurons supplying muscles innervated by the facial nerve was studied in the brain stem of the cat; horseradish peroxidase (HRP) was used as a tracer of retrograde protein transport. One to 15 microliters of HRP was injected into various muscles. Orbicularis oculi and orbicularis oris muscles were represented in the lateral division of the facial nucleus. The platysma, posterior belly of digastric, auricularis superior, and frontalis muscles were represented in the medial division of the facial nucleus. No labeled neuron was found in the trigeminal nerve nucleus or any other brain stem nuclei. The grouping of the motor neurons into relatively discrete areas of the nucleus and the fact that the facial nerve innervates various muscles through separate branches suggest that these motor neurons travel together in discrete groups within the facial nerve trunk. However, orientation of the facial nerve fibers was demonstrated by use of the Marchi method and an osmium stain after complete and partial transection of the nerve at the internal auditory meatus; this showed that the motor axons to the peripheral branches are diffusely located throughout the temporal course of the facial nerve.

Tympanoplasty in geriatric patients: surgical considerations.

The outcomes of tympanoplasty in the elderly are generally no different from those in the young. Although some reports suggest that hearing results were not as good in patients older than 60, the instance of graft failure in these patients did not differ greatly by age. Patients older than 65 do have the highest incidence of perioperative death or complications, with elderly men being at a greater risk than elderly women. The risk is also higher in patients who have concomitant diseases, such as coronary artery disease, congestive heart failure, myocardial infarction, diabetes mellitus, hypertension, renal disease, chronic obstructive pulmonary disease, cerebral vascular disease, dementia, and peripheral vascular disease. The presence of coexisting disease is more important than age itself, although physiologic age is more important than chronological age.

Management of anesthesia in geriatric patients undergoing head and neck surgery.

Surgical outcomes of patients aged 65 and older depend in part on the patient's physiologic status and coexisting disease and whether the surgery is elective or urgent. As our overall population continues to grow older, more elderly patients with head and neck cancers are being scheduled for surgery. In addition to the usual problems of aging, older head and neck surgery patients have unique airway issues that must be addressed preoperatively. Likewise, thorough planning for perioperative management is imperative to reduce morbidity and mortality. Because pharmacokinetics and pharmacodynamics are different in older patients than in younger patients, the administration of anesthesia must be adjusted accordingly.

p53 immunostaining of surgical margins as a predictor of local recurrence in squamous cell carcinoma of the oral cavity and oropharynx.

Local and regional recurrence is the principal reason for treatment failure in squamous cell carcinoma (SCC) of the head and neck. The conventional method of evaluating surgical margins for cellular atypia does not always predict risk of local recurrence accurately. Immunostaining of surgical margins for tumor markers may provide a more precise evaluation of risk of local recurrence. Paraffin-embedded tissue blocks of surgical margins from 24 patients with oral cavity and oropharyngeal squamous cell carcinoma were immunostained for p53 protein. Fifty-eight percent of the patients had at least one margin stain positive for p53, including eight of ten patients whose SCC recurred locally. The sample odds ratio test predicted a 5.333 times higher chance of local recurrence with at least one p53 positive surgical margin. The implications of these results for patient management and further investigations will be discussed.

Excitatory Connections Between CA1 Pyramidal Cells Revealed by Spike Triggered Averaging in Slices of Rat Hippocampus are Partially NMDA Receptor Mediated.

Spike triggered averaging was used to record local circuit connections between pairs of CA1 pyramidal neurons in isolated slices of rat hippocampus. Of 795 pairs of neurons tested, six were connected. These epsps were only partially blocked by 2-amino-5-phosphonovalerate (AP-5), which decreased the amplitude and half width of the epsp, but did not affect the early rising phase. In contrast, 6-cyano-7-nitroquinoxaline-2,3-dione (CNQX) blocked all phases of the epsp and combinations of AP-5 and CNQX blocked the epsp almost entirely. These results indicate that these epsps were mediated by both N-methyl-d-aspartate (NMDA) and non-NMDA excitatory amino acid receptors. Moreover, they exhibited a voltage relation typical of neuronal responses to NMDA, increasing in amplitude and duration as the postsynaptic cell was depolarized. These epsps were brief (10 - 90% rise time < 5 ms, width at half amplitude < 20 ms), indicating a proximal location. Increasing presynaptic firing rate (1 - 4 spikes/s) reduced average epsp amplitude by almost 50%. When epsps were evoked by pairs of spikes (interval 3 - 25 ms), a large response to the first spike precluded a large response to the second. No evidence for selective enhancement of the NMDA receptor component by paired spike activation was found. It is concluded that a significant NMDA receptor mediated input to CA1 is provided by local circuit CA1 - CA1 connections and that these synapses can be demonstrated under control conditions.

Coactivation of Local Circuit NMDA Receptor Mediated epsps Induces Lasting Enhancement of Minimal Schaffer Collateral epsps in Slices of Rat Hippocampus.

Lasting enhancement of minimal Schaffer collateral epsps in CA1 pyramidal neurons was induced when these epsps were coactivated with putative local circuit N-methyl-d-aspartate (NMDA) receptor-mediated epsps. In transverse slices of hippocampus, minimal epsps were evoked by stimulating the Schaffer collateral/commissural pathway within CA3 stratum radiatum and the local circuit axons were stimulated within CA1 stratum oriens or alveus using fine, two barrel glass micropipettes. Minimal Schaffer collateral epsps were insensitive to d-2-amino-5-phosphonovalerate (AP-5) and displayed conventional voltage relations. Local epsps were sensitive to AP-5 and increased in amplitude and duration with membrane depolarization. High frequency tetanic stimulation of the minimal Schaffer collateral epsps induced no lasting enhancement. However, pairing of the Schaffer epsp with a frequency potentiated local epsp resulted in a delayed, but lasting increase in the Schaffer epsp. When the local epsp did not exhibit frequency potentiation during pairing, no enhancement resulted. When either epsp was contaminated with an ipsp, no lasting increase resulted. When transmission through the alveus was blocked by focal application of local anaesthetic, traditional protocols for long-term potentiation (LTP) induction were relatively ineffective. These results indicate that a significant source of the NMDA receptor activation required for the induction of LTP in the Schaffer collateral input to CA1 derives from local circuit connections between CA1 pyramidal neurons and, moreover, that lasting enhancement can be induced with low frequency activation, at postsynaptic resting potential, in the presence of Mg2+ and with local inhibition intact.

Loss of hypoxic ventilatory response following bilateral neck dissection.

Modified radical neck or combined radical and modified radical neck surgery is performed for treatment of head and neck cancer. Because of the extensive nature of the surgery, including dissection around the carotid vessels, we prospectively evaluated hypoxic ventilatory responses preoperatively and postoperatively in five patients. The change in ventilation to percent desaturation varied between -0.22 and -0.60 L/min per percent desaturation in the five study patients. In the postoperative evaluation, two of five patients showed flattened responses compared with the preoperative measurements due to denervation of their carotid bodies. Two patients showed increased responses due to loss of upper airway resistance from tracheostomy. We conclude that after bilateral neck dissection for cancer surgery some patients may lose their hypoxic ventilatory responses due to carotid body denervation.

Comparison of ultrasound-fine needle aspiration and computed tomography in patients undergoing elective neck dissection.

BACKGROUND: Ultrasound of the neck with fine needle aspiration (US-FNA) of suspicious lymph nodes has potential advantages over other radiologic techniques as a screening method for the NO neck in head and neck cancer. METHODS: Twenty-five patients with head and neck cancer who underwent both US of the neck with FNA of any suspicious lymph nodes and neck computed tomography (CT) prior to elective neck dissection were studied. The majority of patients had squamous cell carcinoma (SCC) of the upper aerodigestive tract. Histopathologic results of the neck specimens were compared with each screening technique (palpation, US, US-FNA, CT). RESULTS: Computed tomography (87.9%) and US-FNA (84.9%) had similar overall accuracy in terms of screening the NO neck in our study and were superior to palpation (69.7%) and US alone (72.7%). Specificity was 100% for both CT and US-FNA, with a sensitivity of 60% for CT and 50% for US-FNA. Ultrasound-FNA and CT showed false-negative examinations on virtually the same cases. CONCLUSIONS: Overall, US-FNA was comparable to CT in screening the NO neck in our study. The choice of which modality to employ for imaging the clinically negative neck depends on a number of factors, including the location and clinical extent of the primary tumor as well as the experience and preference of the head and neck surgeon and radiologist.