Avascular midline oropharyngeal anatomy allows for expanded indications for transoral robotic surgery in pediatric patients.

Transoral robotic surgery (TORS) in children is in its infancy, and indications have been primarily limited to lingual tonsillar hypertrophy and superficial mucosal lesions. However, the relatively avascular channel of the midline posterior tongue, vallecula, and posterior hyoid space provides a safe plane of dissection for deep lesions of the tongue and access to structures in the anterior neck. As robotic surgeons gain experience, application of this technology will continue to grow. The method is retrospective case series. We present seven patients who had either a primary (n = 3) or recurrent (n = 4) lingual thyroglossal duct cyst (TGDC) and underwent TORS excision. Four of the seven patients also underwent transoral resection of the central portion of the hyoid bone, while three had central hyoid resection during prior surgery. Two minor complications occurred with no evidence of lesion recurrence after mean follow-up of 19.7 mo. The midline avascular channel of the tongue allows for relatively bloodless surgical access to pathologies of the midline base of tongue and anterior neck. Lingual thyroglossal duct cysts can safely be removed via a TORS approach with evidence of limited recurrence. Robotic technology can provide safe and effective surgical alternatives for children with a variety of pathologies, and we aim to promote the widespread adoption of TORS in pediatric head and neck surgery by sharing our knowledge and clinical experience. Further study and publication are needed to establish safety and efficacy.

New onset dysphagia and pulmonary aspiration following sclerotherapy for a complex cervical venolymphatic malformation in an infant: Case report and review of the literature.

We present the case of a 2-year-old male with a complex left cervical venolymphatic malformation who underwent doxycycline sclerotherapy at 12 months of age complicated by new onset pulmonary aspiration. A review of the literature reveals this to be a rare complication of sclerotherapy and only the second reported case. METHODS: Procedural details with associated imaging including endoscopic airway and swallowing evaluation are included. A literature review of cervical and laryngeal sclerotherapy complications was performed and discussed. RESULTS: A 12-month-old male underwent sclerotherapy with doxycycline for a complex parapharyngeal and paralaryngeal venolymphatic malformation. The postoperative course was complicated by new onset dysphagia, aspiration, and decreased laryngeal sensation. Gastric feeding and swallowing therapy were necessary due to prolonged difficulty. The sclerotherapy treatment resulted in near elimination of the cervical components of the lesion at 12 months follow up. The child progressed to total oral feeding by 17 months post-treatment with no evidence of decreased laryngeal sensation. An extensive literature review identified only one reported case of new onset dysphagia and decreased laryngeal sensation after doxycycline sclerotherapy. CONCLUSIONS: Doxycycline sclerotherapy for cervical venolymphatic malformations rarely can cause adjacent neural injury resulting in laryngeal complications. Our case report and literature review suggest that symptom management and appropriate aspiration precautions are necessary in infants or children with presumed vagus or laryngeal nerve injury, and injury is likely only temporary.

Effects of tolerance induction on the actions of interferon-gamma on porcine cardiac allografts.

It is well known that interferon-gamma (IFN-gamma) not only plays a critical role in antigen-dependent but also in antigen-independent tissue injury; however, it is not clear how tolerance induction affects the actions of IFN-gamma in the transplant setting. To address this question, we compared the effects of IFN-gamma on porcine recipients of near-syngeneic, rejecting, and tolerant heart transplants. IFN-gamma was infused continuously into the left anterior descending artery of hearts transplanted into 3 groups of major histocompatibility complex (MHC) inbred miniature swine, each treated with a 12-day course of cyclosporine A (CyA). Group 1 recipients received a MHC class I disparate heart, group 2 recipients received a near-syngeneic heart, and group 3 recipients were cotransplanted with a MHC class I disparate heart and kidney, which uniformly induces tolerance to both grafts. An additional group of animals was not transplanted but received intracoronary IFN-gamma infusion into their native hearts. IFN-gamma perfusion not only accelerated the acute rejection of MHC class I disparate hearts (mean survival time = 19 +/- 7.21 vs 38 +/- 8.19 days, P = .025), but caused near-syngeneic heart transplants, which otherwise survive indefinitely, to reject within 35 days (n = 3). In contrast, IFN-gamma perfusion had no demonstrable effects on interstitial rejection, the development of vascular lesions, or graft survival in tolerant heart plus kidney allograft recipients (n = 4) or in autologous hearts (n = 2). These results suggest that tolerance induction mitigates the damaging effects of IFN-gamma itself and that the beneficial effects of tolerance induction on acute and chronic rejection may extend to antigen-independent factors like ischemia/reperfusion injury.

Comparison of programmed stimulation and Holter monitoring for predicting long-term efficacy and inefficacy of amiodarone used alone or in combination with a class 1A antiarrhythmic agent in patients with ventricular tachyarrhythmia.

The values of two Holter ambulatory electrocardiographic monitoring criteria and one programmed stimulation efficacy criterion reported to be predictive of the efficacy of amiodarone were compared in 70 patients taking amiodarone for sustained ventricular tachyarrhythmias. At baseline, all patients had ventricular tachycardia inducible by programmed stimulation. After amiodarone loading (935 +/- 271 mg for 16 +/- 7 days), efficacy was determined by a programmed stimulation criterion (ventricular tachycardia no longer inducible or less than or equal to 15 beats) and two Holter monitoring criteria (Holter I = greater than or equal to 85% reduction of ventricular premature complexes and abolition of couplets and triplets in 64 patients who had greater than or equal to 10 ventricular premature complexes/h or couplets or triplets or both before therapy; Holter II = abolition of triplets in 41 patients who had triplets before therapy). Amiodarone was effective in 12 of 70 patients by the programmed stimulation criterion, in 49 of 64 patients by Holter criterion I and in 37 of 41 patients by Holter criterion II. In assessing efficacy of amiodarone, programmed stimulation and Holter criteria were discordant in 69% of patients or more (p less than 0.001). There were 16 recurrences or sudden deaths during the entire follow-up period (19 +/- 19 months). Arrhythmia-free survival rates at 24 months of patients with efficacy and inefficacy by each criterion, respectively, were 90 and 78% by programmed stimulation, 84 and 62% by Holter criterion I (p less than 0.05) and 73 and 50% by Holter criterion II (p less than 0.05).(ABSTRACT TRUNCATED AT 250 WORDS)

Value of Holter monitoring in predicting long-term efficacy and inefficacy of amiodarone used alone and in combination with class 1A antiarrhythmic agents in patients with ventricular tachycardia.

The value of two reported and two new ambulatory electrocardiographic (Holter) criteria was studied in 80 patients taking amiodarone for refractory recurrent sustained ventricular tachycardia. In the 80 patients, the four Holter criteria were as follows: I-85% or greater reduction of ventricular premature complexes and abolition of couplets and nonsustained ventricular tachycardia in 74 patients who had 10 or more ventricular premature complexes/h, or any couplets or nonsustained ventricular tachycardia/24 hours at baseline; II-abolition of nonsustained ventricular tachycardia in 51 patients who had nonsustained ventricular tachycardia at baseline; III-85% or greater reduction of ventricular premature complexes and abolition of nonsustained ventricular tachycardia in 64 patients who had 30 or more ventricular premature complexes/h at baseline; and IV-85% or greater reduction of ventricular premature complexes and abolition of nonsustained ventricular tachycardia in 73 patients who had 10 or more ventricular premature complexes/h at baseline. Amiodarone was judged effective in, respectively, 51 of 74, 44 of 51, 51 of 64 and 61 of 73 patients by criterion I, II, III or IV. During the follow-up period (19 +/- 20 months), there were 19 instances of recurrence of ventricular arrhythmia or sudden death. Actuarial arrhythmia-free survival rate at 24 months was 84, 74, 86 and 85%, respectively, in patients with efficacy by criterion I, II, III or IV and 61, 43, 48 and 39%, respectively, in patients with inefficacy (p less than 0.015 for all). Many patients with efficacy by Holter criteria, however, had a recurrence of arrhythmia, suggesting insensitivity of these Holter criteria.(ABSTRACT TRUNCATED AT 250 WORDS)

Activation mapping in patients with coronary artery disease with multiple ventricular tachycardia configurations: occurrence and therapeutic implications of widely separate apparent sites of origin.

Catheter or intraoperative activation mapping studies, or both, were performed in 17 patients with coronary artery disease with two to four distinct configurations of ventricular tachycardia, resistant to a mean of 12.1 +/- 6.0 antiarrhythmic drug trials per patient. Mapping studies were performed to guide anticipated surgical ablation of arrhythmias. Activation map data were adequate to determine sites of origin of 30 (64%) of 47 observed tachycardia configurations. These 30 ventricular tachycardias (26 observed clinically) were mapped to 22 separate endocardial sites of origin. Sites of origin of distinct tachycardias were identical or closely adjacent (within 3 cm) in six patients and widely separate (greater than or equal to 4 cm) in eight patients (47% of the group). Activation maps were not adequate to determine sites of origin of 17 (36%) of the 47 tachycardias, including all configurations in three patients. Fifteen patients underwent surgery for control of ventricular tachycardia: aggressive, map-guided endocardial resection (mean 26.5 +/- 14.2 cm2) in 12 patients with identified sites of tachycardia origin and extensive resection of visible endocardial scar (2 patients) or encircling endocardial ventriculotomy (1 patient) in those in whom the sites of origin of all clinical tachycardias remained undetermined. Two inoperable patients were treated with amiodarone. During postoperative electrophysiologic tests (11 of 13 surgical survivors), ventricular tachyarrhythmias were initially uninducible in only 4 of 11 patients. However, in two patients only nonclinical arrhythmias (ventricular flutter) were induced. Six (21%) of 29 clinical tachycardias whose sites of origin were either not determined or not resected (right septum or papillary muscle) remained inducible in five patients. Using previously ineffective antiarrhythmic drugs, initially inducible arrhythmias became uninducible (two patients), or harder to induce than preoperatively (five patients). As a result of surgical resections alone or in combination with previously ineffective drugs (and amiodarone in two inoperable patients), there were no recurrences of ventricular tachycardia in 14 (93%) of 15 patients discharged during 19.0 +/- 14.3 months of follow-up study. Thus, activation mapping may commonly reveal separate apparent sites of origin for clinically observed, morphologically distinct, highly drug-refractory ventricular tachycardias in patients with coronary artery disease with multiple tachycardia configurations. Extensive surgical resection of identified sites of origin may be required to ablate arrhythmias in these patients.(ABSTRACT TRUNCATED AT 400 WORDS)

Long-term efficacy of antitachycardia pacing for supraventricular and ventricular tachycardias.

Over a 14-year period, 53 patients received implanted pacemakers to assist in the control of recurrent tachycardias. Indications were: prevention of tachycardia in 2 patients with supraventricular tachycardia (SVT), and 4 with ventricular tachycardia (VT); termination of tachycardia (15 SVT, 20 VT); and long-term periodic programmed electrical stimulation with potential for tachycardia termination (12 VT). Pacemakers for prevention of VT were implanted in 3 patients with prolonged QT interval syndromes and 1 in whom Holter monitoring showed a significant reduction in ectopic activity during pacing. Pacers were implanted for tachycardia termination only after patients underwent a rigorous protocol aimed at achieving 100 trials of the proposed modality. Patients with tachycardia also requiring antibradycardia pacemakers received pacemakers capable of noninvasive programmed stimulation for use during follow-up. There were no tachycardia recurrences among those patients in whom pacemakers were implanted for prevention. Pacers capable of outpatient programmed stimulation were useful, and it may be desirable to expand their use. The 15 patients with pacers designed for termination of SVT were followed for a mean of 68 months. Among these, actuarial continuation of pacing efficacy was 93% at 1 year, and 78% at 5 years. The 20 patients with pacers for termination of VT were followed for a mean of 37 months. Actuarial efficacy was 78% at 1 year, and 55% at 5 years. Sudden death occurred in 4 of these patients, none clearly pacer related. Pacemakers can play a major therapeutic role in some patients with recurrent tachycardias. The role of such pacemakers in patients with VT may be expanded with the advent of combined pacer-defibrillators.(ABSTRACT TRUNCATED AT 250 WORDS)

Prognostic value of the changes in the mode of ventricular tachycardia induction during therapy with amiodarone or amiodarone and a class 1A antiarrhythmic agent.

The prognostic value of 3 previously reported programmed stimulation efficacy criteria was studied in 70 patients taking amiodarone for sustained ventricular tachycardia (VT). At baseline all patients had VT inducible by programmed stimulation. After amiodarone loading (935 +/- 271 mg/day for 16 +/- 7 days), efficacy of amiodarone was determined by 3 programmed stimulation criteria (criterion I = VT not inducible or 15 beats or less; criterion II = VT not inducible or harder to induce; criterion III = VT not easier to induce). Amiodarone was effective in 12, 25 and 49 of 70 patients by criteria I, II and III, respectively. There were 16 recurrences or cardiac arrest during the follow-up period (19 +/- 19 months). Actuarial arrhythmia-free survival rates at 1 and 2 years were: 90% and 90% in patients with efficacy by criterion I and 78% and 78% in patients with inefficacy, respectively; 84% and 84% in patients with efficacy by criterion II and 78% and 78% in patients with inefficacy, respectively; and 80% and 80% in patients with efficacy by criterion III and 79% and 79% in patients with inefficacy, respectively (difference not significant for all). From the results of follow-up at 2 years, sensitivities of criteria I, II and III were 92%, 75% and 33%, respectively. Specificities were 17%, 26% and 70%, respectively, and predictive accuracies were 43%, 43% and 67%, respectively. Thus, patients with efficacy by criterion I appear to have a better prognosis when compared with patients with inefficacy. However, many patients with inefficacy by criterion I had a good outcome (nonspecificity).(ABSTRACT TRUNCATED AT 250 WORDS)

Results of electrophysiologically guided operations for drug-resistant recurrent ventricular tachycardia and ventricular fibrillation due to coronary artery disease.

Over a 39 month period, 143 patients with coronary artery disease had programmed stimulation (PES) for recurrent ventricular tachycardia (VT) or ventricular fibrillation (VF). Twenty-two patients underwent operations. Ages ranged from 40 to 71 years; 20 of the 22 were men. All patients had coronary artery disease and 11 had left ventricular aneurysms. The mean ejection fraction was 31% (16% to 50%). Eighteen of the 22 patients underwent operations for drug-resistant ventricular arrhythmias (more than six different drugs plus drug combinations tested per patient). Nineteen patients had intraoperative mapping, endocardial resection, and/or an encircling endocardial ventriculotomy. Three patients with ischemia-related VT had coronary artery bypass (CABG) alone. The 30 day operative mortality was 14%. Thirteen of 19 (68%) operative survivors were effectively controlled with operation alone or a combination of operation and previously ineffective drug therapy. Of the six patients whose VT was inducible postoperatively, three have experienced episodes of sustained VT and one patient died suddenly. Three of these patients have the automatic implantable defibrillator. Operation guided by endocardial mapping is effective alone or in combination with drugs in this select group of patients. If the patients' VT was uninducible postoperatively with or without the addition of antiarrhythmic therapy, late deaths (3/19) were due to poor myocardial reserve and coronary artery disease, not the reemergence of sustained ventricular arrhythmias during a mean follow-up of 15 months.

Comparison of burst pacing, autodecremental (ramp) pacing, and universal pacing for termination of ventricular tachycardia.

This study was designed to test the comparative efficacy of burst pacing, autodecremental (ramp) pacing, and universal (steep ramp) pacing for termination of ventricular tachycardia. A prospective, randomized sequence cross-over design was used to achieve comparisons of the pacing modalities that were matched for patient, day, and ventricular tachycardia characteristics. Thirty eight patients were enrolled, whose ventricular tachycardia was well-enough tolerated to be reinduced, and tested with 3 pacing modalities. There were 27 series 1 patients in which the pacing modalities were nonsynchronized burst pacing, synchronized burst pacing, and ramp pacing. The 11 patients in series 2 were tested with synchronized burst pacing, ramp pacing, and universal pacing. All pacing methods proved to be comparable in their ability to terminate ventricular tachycardia (p = NS). The 2 burst methods required the fewest number of attempts (significant vs ramp pacing). Universal pacing required the fewest number of stimuli. The mean paced cycle length was similar will all methods. The shortest paced cycle lengths were found with the autodecremental and universal methods because of their ramp patterns. It is concluded that burst, ramp, and universal pacing are of similar efficacy, although ramps were least efficient. Choice of a modality depends on operator preference, and individual patient response.

Diagnostic and surgical challenge: middle ear dermoid cyst in 12 month old with branchio-oto-renal syndrome and multiple middle-ear congenital anomalies.

Described is the first case report, to our knowledge, of a middle-ear dermoid in a child with branchio-oto-renal (BOR) syndrome. Radiographic, pathologic, and intraoperative figures are shown. This was a diagnostic and surgical challenge as the presentation was similar to a congenital cholesteatoma and the child had numerous significant temporal bone abnormalities. After the intraoperative findings suggested a non-destructive process, the treatment strategy was altered. This case reiterates the need for a cautious, flexible operative approach in a syndromic child. Included is a relevant review of the literature and a detailed clinical analysis.

The impact of waiving compulsory retirement.

A variety of forces operated synergistically to bring about quick development and passage in April of amendments to the Age Discrimination in Employment Act of 1967. Consequently, administrators must reassess the age-related assumptions underlying personnel policies.

Attenuation by artificial fogs in the visible, near infrared, and far infrared.

The attenuation coefficient ratio (alphalambda/alpha(o.546)) for artificial fogs has been measured at 345 micro, coefficient ratios at 0.436 micro, 1.01 micro, 3.5 micro, 10 micro, and 13.5 micro were also measured so that a comparison between artificial fogs and natural fogs could be made. By comparing our results with others on natural fogs and with the theoretical work of others in the visible and near ir, we have concluded that our artificial fogs closely resemble natural fogs. We conclude, therefore, that alpha(O.345)/alpha(o.546) is representative of real fogs. Artificial fogs are generated and allowed to dissipate during which time attenuation of light at several wavelengths is recorded. The green line of the mercury arc at 0.546 micro was used as the standard of comparison. For radiation at 345 micro,(alpha345/alphaO.546) = 0.014 +/- 0.009 during the generation time of the fog and 0.021 +/- 0.006 during the time the fog is allowed to dissipate.

Does occupational exposure to silica cause lung cancer?

Silica is not generally considered to be a carcinogen, however, occupations characterized by high exposure to crystalline silica have excessive rates of lung cancer mortality. Respiratory cancer excesses have been reported from North America and from Europe for the following dusty trades in which exposure to silica is a common factor: iron and steel foundry workers, steel casting workers, sand blasters, metal molders, non-uranium miners, and ceramic workers. These findings have been reinforced by two reports from the Swedish Pneumoconiosis Register and the Ontario Ministry of Labor indicating that silicotics have statistically significant risks of lung cancer mortality. Animal studies suggest that silica can be an initiating carcinogen or can act as a cocarcinogen or promoter when combined with benzo(a)pyrene. We propose three candidate hypotheses and two pathways for silicocarcinogenesis.

Accelerated life testing of prosthetic heart valves.

Throughout the years of prosthetic heart valve development, the long-term durability of heart valve development, the long-term durability of heart valves has been studied by accelerated life-cycle testing. Accelerated testing has been used to study materials, design concepts, design modifications, and durability variations caused by changes in manufacturing techniques. As with all in vitro tests, knowledge of the limitations of the test is of paramount importance in analyzing the results. The greatest strength of the accelerated cycle test, however, lies in comparisons of one valve with another. It is in this manner that new prototypes, new materials, or slight modifications in valve design can be gauged with respect to valve life. Valves with long clinical history can be used as standards. Whether a test valve will have a longer or shorter expected life than the standard can be estimated in a relatively short period in side-by-side test runs.

Implantable pacers for tachycardia termination: stimulation techniques and long-term efficacy.

The long-term efficacy of pacing for termination of supraventricular tachycardia (SVT) and ventricular tachycardia (VT) was reviewed. Increasingly complex and sophisticated antitachycardia pacing stimulation patterns have evolved, and are outlined. Although excellent results are reported with simple patterns, it may be that the more complex algorithms increase the percentage of tachycardia patients who may be candidates for implantation of a device. In the papers reviewed, there were 460 patients, 268 with SVT, and 192 with VT. Results were judged to be good-excellent in 96.5% of both VT and SVT groups.