Krishnamurthi Sundaram

Systematic review of laryngeal reinnervation techniques.

OBJECTIVE: To systematically review outcomes of reinnervation techniques for the management of unilateral vocal fold paralysis (UVFP). DATA SOURCES: Medline and Cochrane databases for English-language studies published between 1966 and 2009 on the surgical management of UVFP. REVIEW METHODS: Studies were excluded if they reported on bilateral vocal fold paralysis, used nonhuman subjects, or did not assess clinical outcomes. Outcomes of interest were visual analysis, acoustic analysis, perceptual analysis, and electromyography. RESULTS: Of 686 initial studies, 14 studies encompassing 329 patients were eligible for analysis. All studies had a case-series design. Of reported patients, 60.2 percent were men, with mean age of 51 years (range, 12-79 years). The most common reinnervation technique was ansa cervicalis-to-recurrent laryngeal nerve (RLN), which was most commonly performed after thyroidectomy (43.5%). Other techniques with reportable outcomes included primary RLN anastomosis, ansa-to-RLN combined with cricothyroid muscle-nerve-muscle pedicle, ansa-to-thyroarytenoid neural implantation, ansa-to-thyroarytenoid neuromuscular pedicle, and hypoglossal-to-RLN. Median postsurgical follow-up was 12 months, and mean time to first signs of reinnervation was 4.5 months (SD 2.9 months). Visual analysis of glottic gap showed the greatest mean improvement with ansa-to-RLN, from 2.25 (SD 0.886) to 0.75 (SD 0.886) mm (P < 0.01). Acoustic analysis showed greatest improvement with neural implantation, with a change in mean phonation time from seven (SD 1.22) to 16 (SD 5.52) seconds (P < 0.01). Perceptual analysis and electromyography demonstrated improvement in all studies. CONCLUSION: Reinnervation is effective in the management of UVFP, although the specific method may be dictated by anatomical limitations. Prospective studies utilizing uniform and consistent outcome parameters are necessary.

Laryngeal Nerve Monitoring Current Utilization among Head and Neck Surgeons

Objective. There is continued debate over the value of laryngeal nerve monitoring (LNM) during thyroidectomy. Previous studies have suggested that utilization of electromyographic endotracheal tubes for neuromonitoring is limited. We queried head and neck surgeons regarding their attitudes toward LNM. Study Design. Voluntary survey. Setting. Internet based. Subjects and Methods. An anonymous survey of the members of the American Head and Neck Society was performed. Information was collected on participants’ training history, practice setting, years of experience, and annual volume of thyroid and parathyroid surgeries. Participants’ use of LNM and their beliefs regarding possible benefits were assessed. Results. One hundred seventy surveys were completed (18% response rate). Of respondents, 65% use LNM in at least some thyroid and parathyroid cases, 37% always and 28% sometimes. The most commonly cited reasons for LNM use were “medical-legal protection” and “increased confidence.” Comparing otolaryngologists to general surgeons, 43% versus 17% (P = .016) always use LNM, 27% versus 36% sometimes use monitoring, and 30% versus 47% never use monitoring. Younger surgeons were more likely to use LNM. Conclusion. Currently, no consensus exists regarding the use of LNM during thyroid and parathyroid surgery. Our results suggest that LNM use has become more widespread. Irrespective of the reasons surgeons are adopting LNM, if this trend continues, LNM may eventually become routine practice among head and neck surgeons.

Carcinoma of the Oropharynx: Factors Affecting Outcome

Objectives/Hypothesis: To assess the value of both patient‐ and tumor‐related factors of oropharyngeal squamous cell carcinoma in predicting patient outcome, with respect to the three primary subsites of the disease. It was hypothesized that the subsite has a significant impact on outcome.

Branchial Cleft Cyst Carcinoma: Myth or Reality?

Skepticism has surrounded the existence of branchial cleft carcinoma since the entity was first described in 1882. However, a landmark work of 1950 established four criteria for the diagnosis of branchial cleft carcinoma, the most important criterion being histologic proof of carcinoma arising from a normal cyst epithelium. Of the 43 cases found in an extensive review of the literature, only 7 cases have satisfied all four of the criteria. To this we add 2 patients who had recurrent infections of a cervical cyst as children and later developed carcinoma within these structures. Additionally, we propose a minor modification to the 1950 criteria and a paradigm for diagnosis and management of these lesions.

Latissimus dorsi myocutaneous flap for secondary head and neck reconstruction

PURPOSE To review our experience and results with the use of pedicled latissimus dorsi myocutaneous flap (LDMF) for secondary reconstruction in head and neck surgery. METHODS Twenty-two patients had LDMF, 17 of them for secondary reconstruction. Data were collected regarding the primary surgery, primary method of reconstruction, indication for secondary reconstruction, and outcome. RESULTS Seventeen LDMF procedures were performed for secondary reconstruction. Flap success rate was 100%. Reconstructive goals were achieved immediately in 16 (94.1%) patients. CONCLUSION LDMF is a thin flap with a large surface area and a long pedicle that allows it to reach any region in the head, neck, and scalp. Its main disadvantages are the need for lateral positioning of the patient and the fact that its pedicle is not protected with muscle. In our experience, LDMF provides an excellent reconstructive option especially in complicated cases of secondary reconstruction. It may be used in cases where a free flap is usually used, but with significantly reduced surgical time.

Prevention of unplanned pharyngocutaneous fistula in salvage laryngectomy

Pharyngocutaneous fistula formation is the most common complication after laryngectomy. Salvage laryngectomies in patients treated with organ-preservation protocols are associated with higher rates of postoperative complications (13%-39%). These patients are best repaired by using regional myocutaneous flaps or free-tissue transfers. We present the formula used by the senior author at the Downstate Medical Center and affiliated hospitals in his last 11 cases, in which healing occurred without unplanned fistula formation, and length of stay was 10 days. Prior to the introduction of the formula, out of nine salvage laryngectomies (historical controls), the same surgeon had six cases of wound dehiscence and unplanned occurrence of a pharyngocutaneous fistula (67%). In these nine cases, one or more components of the formula were not used. Results using this fistula reduction formula appear superior to other reported attempts at fistula rate reduction and thus warrant reporting. Institutional review board approval was obtained for this study.

Determination of the function of the internal branch of the superior laryngeal nerve after thyroidectomy.

Several unique complications of thyroidectomy exist because of its regional anatomy; they are well studied and reported. A majority of thyroidectomy patients report vague upper aerodigestive tract complaints. Despite this, no formal assessment of the integrity of the internal branch of the superior laryngeal nerve after thyroidectomy exists in the literature.

Laryngospasm, central and obstructive apnea during seizures: Defining pathophysiology for sudden death in a rat model

Seizure spread into the autonomic nervous system can result in life-threatening cardiovascular and respiratory dysfunction. Here we report on a less-studied consequence of such autonomic derangements-the possibility of laryngospasm and upper-airway occlusion. We used parenteral kainic acid to induce recurring seizures in urethane-anesthetized Sprague Dawley rats. EEG recordings and combinations of cardiopulmonary monitoring, including video laryngoscopy, were performed during multi-unit recordings of recurrent laryngeal nerve (RLN) activity or head-out plethysmography with or without endotracheal intubation. Controlled occlusions of a tracheal tube were used to study the kinetics of cardiac and respiratory changes after sudden obstruction. Seizure activity caused significant firing increases in the RLN that were associated with abnormal, high-frequency movements of the vocal folds. Partial airway obstruction from laryngospasm was evident in plethysmograms and was prevented by intubation. Complete glottic closure (confirmed by laryngoscopy) occurred in a subset of non-intubated animals in association with the largest increases in RLN activity, and cessation of airflow was followed in all obstructed animals within tens of seconds by ST-segment elevation, bradycardia, and death. Periods of central apnea occurred in both intubated and non-intubated rats during seizures for periods up to 33s and were associated with modestly increased RLN activity, minimal cardiac derangements, and an open airway on laryngoscopy. In controlled complete airway occlusions, respiratory effort to inspire progressively increased, then ceased, usually in less than 1min. Respiratory arrest was associated with left ventricular dilatation and eventual asystole, an elevation of systemic blood pressure, and complete glottic closure. Severe laryngospasm contributed to the seizure- and hypoxemia-induced conditions that resulted in sudden death in our rat model, and we suggest that this mechanism could contribute to sudden death in epilepsy.

Seizure-associated central apnea in a rat model: Evidence for resetting the respiratory rhythm and activation of the diving reflex

Respiratory derangements, including irregular, tachypnic breathing and central or obstructive apnea can be consequences of seizure activity in epilepsy patients and animal models. Periods of seizure-associated central apnea, defined as periods >1s with rapid onset and offset of no airflow during plethysmography, suggest that seizures spread to brainstem respiratory regions to disrupt breathing. We sought to characterize seizure-associated central apneic episodes as an indicator of seizure impact on the respiratory rhythm in rats anesthetized with urethane and given parenteral kainic acid to induce recurring seizures. We measured central apneic period onsets and offsets to determine if onset-offset relations were a consequence of 1) a reset of the respiratory rhythm, 2) a transient pausing of the respiratory rhythm, resuming from the pause point at the end of the apneic period, 3) a transient suppression of respiratory behavior with apnea offset predicted by a continuation of the breathing pattern preceding apnea, or 4) a random re-entry into the respiratory cycle. Animals were monitored with continuous ECG, EEG, and plethysmography. One hundred ninety central apnea episodes (1.04 to 36.18s, mean: 3.2±3.7s) were recorded during seizure activity from 7 rats with multiple apneic episodes. The majority of apneic period onsets occurred during expiration (125/161 apneic episodes, 78%). In either expiration or inspiration, apneic onsets tended to occur late in the cycle, i.e. between the time of the peak and end of expiration (82/125, 66%) or inspiration (34/36, 94%). Apneic period offsets were more uniformly distributed between early and late expiration (27%, 34%) and inspiration (16%, 23%). Differences between the respiratory phase at the onset of apnea and the corresponding offset phase varied widely, even within individual animals. Each central apneic episode was associated with a high frequency event in EEG or ECG records at onset. High frequency events that were not associated with flatline plethysmographs revealed a constant plethysmograph pattern within each animal, suggesting a clear reset of the respiratory rhythm. The respiratory rhythm became highly variable after about 1s, however, accounting for the unpredictability of the offset phase. The dissociation of respiratory rhythm reset from the cessation of airflow also suggested that central apneic periods involved activation of brainstem regions serving the diving reflex to eliminate the expression of respiratory movements. This conclusion was supported by the decreased heart rate as a function of apnea duration. We conclude that seizure-associated central apnea episodes are associated with 1) a reset of the respiratory rhythm, and 2) activation of brainstem regions serving the diving reflex to suppress respiratory behavior. The significance of these conclusions is that these details of seizure impact on brainstem circuitry represent metrics for assessing seizure spread and potentially subclassifying seizure patterns.

Validation of the Modified Brief Fatigue Inventory in Head and Neck Cancer Patients

Objective The aim of this study is to validate the Modified Brief Fatigue Inventory (MBFI). This is the first instrument designed to measure intensity and frequency of fatigue specifically in head and neck cancer patients, potentially allowing objective measurement in addressing this common symptom in a concise yet thorough fashion. Study Design Survey validation. Setting Academic tertiary medical center. Subjects and Methods The 9-item MBFI was administered to 52 consecutive cancer patients and 57 consecutive controls. Demographics, comorbidities, cancer site, and cancer stage were recorded. Psychometric properties and predictors of the MBFI were analyzed. Results The MBFI 1-week test-retest reliability was excellent (r = 0.800, P < .001). Internal consistency was also excellent (Cronbach’s α = 0.938). Construct validity of the MBFI compared with the previously validated Multidimensional Fatigue Symptom Inventory–Short Form was excellent (r = 0.814, P < .001). Discriminant validity of cancer patients vs controls was significant (P = .027). Predictors of increased MBFI score included American Society of Anesthesiologists (comorbidity) score (bivariate analysis, r = 0.287, P = .039), cancer stage (analysis of variance, P = .007), and adjuvant radiotherapy (t test, P = .016). Cancer stage and comorbidity were further correlated with a multiple regression linear model. No significant relationship was found with age, sex, marital status, education, ethnicity, feeding tube, tracheostomy, or laryngectomy. Conclusion The MBFI is a reliable and valid tool for measuring fatigue levels in head and neck cancer patients. In the context of initial assessment or posttreatment trending, this brief survey can be rapidly administered, providing valuable objective data on a very common and potentially debilitating symptom.