Transition paths of marine debris and the stability of the garbage patches.

We used transition path theory (TPT) to infer "reactive" pathways of floating marine debris trajectories. The TPT analysis was applied on a pollution-aware time-homogeneous Markov chain model constructed from trajectories produced by satellite-tracked undrogued buoys from the National Oceanic and Atmospheric Administration's Global Drifter Program. The latter involved coping with the openness of the system in physical space, which further required an adaptation of the standard TPT setting. Directly connecting pollution sources along coastlines with garbage patches of varied strengths, the unveiled reactive pollution routes represent alternative targets for ocean cleanup efforts. Among our specific findings we highlight: constraining a highly probable pollution source for the Great Pacific garbage patch; characterizing the weakness of the Indian Ocean gyre as a trap for plastic waste; and unveiling a tendency of the subtropical gyres to export garbage toward the coastlines rather than to other gyres in the event of anomalously intense winds.

Markov-chain-inspired search for MH370.

Markov-chain models are constructed for the probabilistic description of the drift of marine debris from Malaysian Airlines flight MH370. En route from Kuala Lumpur to Beijing, MH370 mysteriously disappeared in the southeastern Indian Ocean on 8 March 2014, somewhere along the arc of the 7th ping ring around the Inmarsat-3F1 satellite position when the airplane lost contact. The models are obtained by discretizing the motion of undrogued satellite-tracked surface drifting buoys from the global historical data bank. A spectral analysis, Bayesian estimation, and the computation of most probable paths between the Inmarsat arc and confirmed airplane debris beaching sites are shown to constrain the crash site, near 25°S on the Inmarsat arc.

The evolution of tonsil surgery and rethinking the surgical approach to obstructive sleep-disordered breathing in children.

Within the last 10 to 15 years, a significant amount of research in tonsil surgery has focused on reduction of post-operative pain and recovery time. In order to minimize or avoid morbidity, a number of otolaryngologists in the United States and Europe have revived a historical procedure, previously known as 'tonsillotomy', specifically for those patients with obstructive sleep-disordered breathing (OSDB) due to adenotonsillar hypertrophy. More recently, surgeons have used terms such as partial tonsillectomy, partial intracapsular tonsillectomy or subtotal tonsillectomy to describe their procedure and have employed a variety of modern instrumentation. This return to a 'partial' procedure has generated a debate similar to that which occurred amongst tonsil surgeons about 100 years ago, when tonsillotomy was the most commonly performed procedure. Today, concerns about regrowth and problems with infection of the remaining tonsillar tissue have been raised. Such concerns, combined with an incomplete understanding of why the 'partial' procedure was abandoned in the early twentieth century, may explain why tonsil surgeons hesitate to change their approach to patients with OSDB due to adenotonsillar hypertrophy. These issues can be addressed in a meaningful way only through a detailed review of the evolution of tonsil surgery, which is presented here. This information, along with a summary of the last 10 years' experience with these techniques, supports the use of a 'partial' procedure in children with OSDB due to adenotonsillar hypertrophy. Future areas of research are also discussed.

Cervical presentations of thymic anomalies in children.

OBJECTIVE: To better define the clinical manifestations, radiologic imaging and the surgical management of cervical thymic lesions in children. STUDY DESIGN: Multi-center retrospective case review. METHODS: The charts of all children with pathologically confirmed thymic lesions at six children's hospitals (1990-2002) were reviewed for demographics, physical findings, X-ray findings, operative outcomes and pathology. RESULTS: There were a total of 15 children, 2 of whom had ectopic cervical thymus and 13 who had thymic cysts. They ranged in age from 1 month to 18 years. Thymic lesions were more common in males. Ectopic cervical thymus was best defined by MRI whereas thymic cyst had a more consistent appearance on CT. All children had successful surgical resection with no recorded complications or recurrences. CONCLUSIONS: Cervical thymic lesions are rare. Ectopic cervical thymus tends to be found primarily in infants whereas thymic cysts occur in a wider age range. Radiologic imaging is important but is not histologically specific. Definitive diagnosis and cure requires complete surgical excision.

The impact of airbags and seat belts on the incidence and severity of maxillofacial injuries in automobile accidents in New York State.

OBJECTIVE: To evaluate the effect driver-side and passenger-side airbags have had on the incidence and severity of maxillofacial trauma in victims of automobile accidents. DESIGN: Retrospective analysis of all automobile (passenger cars and light trucks) accidents reported in 1994. SETTING: New York State. PATIENTS: Of the 595910 individuals involved in motor vehicle accidents in New York in 1994, 377054 individuals were initially selected from accidents involving cars and light trucks. Of this subset, 164238 drivers and 62755 right front passengers were selected for analysis. MAIN OUTCOME MEASURES: Each case is described in a single record with approximately 100 variables describing the accident, eg, vehicle, safety equipment installed and utilized or deployed, occupant position, patient demographics, International Classification of Diseases, Ninth Revision, Clinical Modification (ICD-9-CM) diagnoses, and procedural treatments rendered. A maxillofacial trauma severity scale was devised, based on the ICD-9-CM diagnoses. RESULTS: Individuals using airbags and seat belts sustained facial injuries at a rate of 1 in 449, compared with a rate of 1 in 40 for individuals who did not use seat belts or airbags (P<.001). Those using airbags alone sustained facial injuries at the intermediate rate of 1 in 148, and victims using seat belts without airbags demonstrated an injury rate of 1 in 217 (P<.001). CONCLUSION: Use of driver-side airbags, when combined with use of seat belts, has resulted in a decrease in the incidence and severity of maxillofacial trauma.

[Neoadjuvant chemotherapy in head and neck cancer] / Neoadjuváns kemoterápia fej-nyaki laphámrákban.

BACKGROUND: Neoadjuvant chemotherapy has an increasing role in multimodality treatment of advanced head and neck cancer. In this paper we summarize our first results with this treatment. METHOD: Thirty-five, previously untreated, mostly inoperable head and neck cancer patients were given two cycles of Cisplatin and 5FU chemotherapy. We continued the therapy only in case of regression until four cycles, then the patients received surgical and/or radiotherapy according to their status. After the treatment patients' status was regularly evaluated. RESULTS: We detected 4 complete and 20 partial responses after the chemotherapy. Three patients became eligible for a radical operation. At this moment 10 patients are free of tumor, 8 patients died in consequence of the tumor, we have no data in 3 cases, 3 patients are given palliative therapy because of progression, 4 patients are receiving radiotherapy and 7 patients with partial response are candidates for further active oncotherapy. CONCLUSIONS: Although the number of the patients we treated is too small for a statistical analysis, our results are similar to the conclusion of the large randomized studies: after neoadjuvant chemotherapy of advanced head and neck cancer partial response can improve the result of surgical or radiological treatment. Neoadjuvant chemotherapy does not improve survival in advanced head and neck cancer, but it is of great importance because of better quality of life of patients, especially those who had organ preserving therapy.

Comparison of power-assisted adenoidectomy vs adenoid curette adenoidectomy.

OBJECTIVE: To compare the safety and efficacy of power-assisted adenoidectomy (PAA) vs adenoid curette adenoidectomy (ACA). DESIGN: A prospective randomized study. SETTING: Children's hospital of a tertiary care medical center. PATIENTS: Ninety patients (aged 1-13 years) underwent PAA, and 87 patients (aged 1-12 years) underwent ACA. MAIN OUTCOME MEASURES: The parameters evaluated were operative time, blood loss, completeness and depth of resection, injuries to surrounding structures, short- and long-term complications, surgeon satisfaction with the procedure, and parents' assessment of the patient's postoperative recovery period. RESULTS: The PAA was 20% faster (P<.001) and had 27% less blood loss (P<.001) than the ACA. It provided a more complete resection(P<.001) and better control of the depth of resection (P<.05). Surgeon satisfaction was greater with PAA (P<.001). There was no difference in the recovery period or parent satisfaction. One patient in the PAA group returned to the operating room for control of postoperative bleeding, and 1 child in the ACA group returned to the hospital for postoperative dehydration. CONCLUSION: The PAA provides a faster, dryer, more complete, and more surgically satisfying resection than the ACA.

Familial occurrence of acinic cell carcinoma of the parotid gland.

We report the familial occurrence of acinic cell carcinoma involving the parotid gland, the first such report of which we are aware. The familial occurrence of any salivary gland neoplasm is rare. Several reports are present in the literature, including pleomorphic adenoma, Warthin tumor, carcinoma of the submandibular gland, and malignant lymphoepithelial lesion. We report the case of a 35-year-old man who underwent excision of a left parotid gland acinic cell carcinoma. Eight years later, his daughter presented at the age of 16 years with a nontender parotid gland mass that was excised and found also to be acinic cell carcinoma. The histologic features of both neoplasms were typical of acinic cell carcinoma. While this may represent a coincidental event, the possibility that this familial occurrence is a manifestation of common genetic or environmental risk cannot be excluded.

Evaluation of orbital stress dissipation in pediatric and adult skulls using electronic speckle pattern interferometry.

OBJECTIVES: To measure and quantitatively compare the degree of force dissipation in pediatric and adult skulls subjected to similar dynamic forces. DESIGN: An anatomical study using electronic speckle pattern interferometry, which allows generation of displacement vectors after application of a force. SUBJECTS: Five human skulls (3 pediatric and 2 adult). INTERVENTION: Each skull was subjected to a reproducible and quantifiable force created by a steel ball pendulum striking a precise periorbital focus: (1) infraorbital foramen, (2) supraorbital notch, (3) malar eminence, and (4) nasofrontal suture. Electronic speckle pattern interferometry was used to construct interferogram fringe patterns to determine skull regions with the greatest degree of displacement. RESULTS: Interferogram analysis revealed that the adult skull has a tendency to dissipate force with minimal resultant displacement. In contrast, the pediatric skulls demonstrated greater displacements (ie, increased fringe density) at the same periorbital foci. CONCLUSIONS: The pediatric skull dissipates periorbital stress differently than the adult skull, as illustrated by quantitative interferogram analysis. This finding parallels clinical data that demonstrate a varying pattern of fractures in pediatric and adult skulls related to craniofacial development.

Starplasty: a new technique of pediatric tracheotomy.

OBJECTIVE: To report a new technique of pediatric tracheotomy that reduces the problems of pneumothorax and recannulation after accidental decannulation in a recently performed tracheotomy. DESIGN: Retrospective chart review for 1990-1997. PATIENTS: Sixty-eight children aged between 2 days and 14 years. METHOD: The starplasty procedure is based on the geometry of a 3-dimensional Z-plasty. The technique of the procedure is described and illustrated in detail. RESULTS: There were 27 short-term complications, including 4 accidental decannulations. There were no instances of pneumothorax or tracheotomy-related deaths. There were 25 long-term minor complications. There were no instances of tracheotomy-related death, suprastomal collapse, or tracheal stenosis. Thirty-eight children remain tracheotomy tube dependent, 17 underwent decannulation, 7 died of primary disease, and 6 were lost to follow-up. All 17 children who underwent decannulation have a persistent tracheocutaneous fistula. CONCLUSIONS: I conclude that starplasty reduces the incidence of major complications and death. Its only drawback seems to be persistent tracheocutaneous fistula.

Safety of powered instrumentation for adenoidectomy.

A recent study established the utility of an endoscopic shaver for adenoidectomy in children by the transoral approach and showed that power assisted adenoidectomy (PAA) was significantly faster with a trend toward decreased blood loss. The purpose of this study was to demonstrate the safety of power assisted adenoidectomy in a large cohort of patients. A retrospective review was performed of 329 patients who had adenoidectomy by powered instrumentation. Postoperative complications were documented and compared with a similar group that had curette adenoidectomy. Complications watched for included prolonged recovery, postoperative hemorrhage, readmission for dehydration, velopharyngeal insufficiency, and nasopharyngeal stenosis. No postoperative complications were seen in the power assisted adenoidectomy group. This review confirms the safety of power assisted adenoidectomy.

First branchial cleft anomalies: a study of 39 cases and a review of the literature.

OBJECTIVES: To identify the clinical and anatomical presentations and to discuss the guidelines for surgical management of anomalies of the first branchial cleft. DESIGN: Retrospective study. SETTING: Three tertiary care centers. PATIENTS: Thirty-nine patients with first branchial cleft anomalies operated on between 1980 and 1996. INTERVENTION: All patients were treated surgically. Complete removal of the lesion required superficial parotidectomy with facial nerve dissection in 36 cases. The relationship of the facial nerve and anomalies is discussed. RESULTS: Anatomically, 3 types of first branchial cleft anomalies are identified: fistulas (n=11), sinuses (n=20), and cysts (n=8). Clinically, 3 types of presentation are noted: chronic purulent drainage from the ear (n=12), periauricular swelling in the parotid area (n=18), and abscess or persistent fistula in the neck located above a horizontal plane passing through the hyoid bone (n=21). A membranous attachment between the floor of the external auditory canal and the tympanic membrane was observed in 10% of cases. The facial nerve was located lateral to the anomaly in 39% of cases. CONCLUSIONS: Before definitive surgery, many patients (n=17) underwent incision and drainage for infection owing to the difficulties in diagnosing this anomaly. Wide exposure is necessary in most cases, and a standard parotidectomy incision allows adequate exposure of the anomaly and preservation of the facial nerve. Complete removal without complications depends on a good understanding of regional embryogenesis, a knowledge of the circumstances surrounding discovery, an awareness of the different anatomical presentations, and a readiness to identify and protect the facial nerve during resection.

Pediatric mandibular fractures.

Over the last 20 years, a revolution in the management of facial fractures has taken place. Refinements in biocompatible materials of great delicacy and strength along with advances in our understanding of biomechanics of the face, have rendered complex injuries consistently amenable to accurate 3-dimensional reconstruction. Furthermore, with the availability of education in the techniques of internal rigid fixation, these advanced techniques have become routine practice in adults. However, the suitability of rigid internal fixation for children remains controversial. There are many concerns about the effect of implanted hardware in the mandible of a growing child. In addition, some evidence suggests that the elevation of functional matrix off of bone may result in alterations in development. The goal is to restore the underlying bony architecture to its pre-injury position in a stable fashion, with a minimal of aesthetic and functional impairment. However, in children the treatment of bony injuries is most easily accomplished by techniques that may adversely effect craniofacial development. While it is not entirely possible to resolve this dilemma, there exists an extensive body of experimental and clinical information on the appropriate management of pediatric mandibular fractures which can be used to formulate a rational treatment plan for most cases. This paper presents an overview of the contemporary understanding and application of these treatment principles.

Power-assisted adenoidectomy.

OBJECTIVE: To quantify that the use of powered instrumentation for adenoidectomy is an improvement over traditional techniques. DESIGN: Retrospective case series of 40 consecutive children undergoing power-assisted adenoidectomy compared with 40 consecutive children undergoing conventional transoral adenoidectomy with a curet. SETTINGS: Tertiary care center. MAIN OUTCOME MEASURES: Operative time, blood loss, length of hospitalization, and complications. RESULTS: With power-assisted adenoidectomy, the mean operative time was significantly faster (11 minutes vs 19 minutes for the conventional method), mean blood loss was not significantly different (22 mL vs 32 mL for the conventional method), mean length of hospitalization after the procedure was not significantly different (2.95 hours vs 2.8 hours for the conventional method), and there were no surgical complications with either technique. CONCLUSION: In comparison with conventional techniques, power-assisted adenoidectomy provides significant advantages that are subjectively apparent but can also be objectively measured.

p53 protein expression in benign lesions of the upper respiratory tract.

OBJECTIVE: p53 is a tumor suppressor gene that is lost or mutated in most forms of human malignancy. There are, however, very few studies evaluating p53 expression in normal epithelium or benign lesions. DESIGN: We screened for p53 protein expression in a variety of benign epithelial lesions of upper respiratory tract using monoclonal antibody DO-1 on paraffin-embedded material. SUBJECTS: We studied a total of 109 cases: 16 cases of juvenile and 36 cases of adult laryngeal papillomatosis, 10 cases each of laryngeal nodules and laryngeal polyps, 17 cases of inverted papilloma, and 20 cases of nasal polyps. RESULTS: Nuclear immunoreactivity for p53 protein was demonstrated in 14 (88%) of 16 cases of juvenile laryngeal papillomatosis, 33 (92%) of 36 cases of adult laryngeal papillomatosis, 4 (40%) of 10 cases of laryngeal nodules, 8 (80%) of 10 cases of laryngeal polyps, 7 (41%) of 17 cases of inverted papilloma, and 2 (10%) of 20 cases of nasal polyps. These results pertained only to the basal epithelial layer in all cases of laryngeal nodules, laryngeal polyps, and nasal polyps. Intermediate layer cells were also positive for p53 in the majority of the cases of both juvenile (69%) and adult (75%) laryngeal papillomatosis and in a minority of the cases of inverted papilloma (18%). CONCLUSIONS: Overexpression of p53 protein is commonly demonstrable in benign epithelial lesions of the upper respiratory tract. This observation suggests that p53 protein accumulation may occur in the absence of mutation of the p53 gene and may correlate with epithelial proliferative activity.

Management of facial trauma in children.

In today's fast-paced society, many children sustain severe maxillofacial injuries that require surgical reconstruction. The factor that differentiates the treatment of pediatric facial fractures from those of adults is facial growth. Anticipation of mandibular growth facilitates repair because most injuries can be treated with intermaxillary fixation. Midfacial injuries, on the other hand, may be more sensitive to alterations of facial growth, and complex cases require more sophisticated correction. The techniques of three-dimensional reconstruction of complex facial fractures has been facilitated greatly by the use of a rigid plating system, wide craniofacial exposure, and bone grafting. These techniques have sound theoretic and practical applications in severe pediatric facial trauma.

Orbital fractures in children.

OBJECTIVE: To determine if the pattern of orbital fractures may be influenced by the changing craniofacial ratio of the growing child, as the orbit is the boundary between the face and the cranium. DESIGN: Retrospective case series of 40 patients between the ages of 1 year and 16 years with orbital fractures. SETTING: The Albany (NY) Medical Center Hospital, a tertiary level 1 trauma center. OUTCOME MEASURES: The sex, age, site, and mechanism of injury, associated injury, and treatment methods for children admitted to the Albany Medical Center Hospital with orbital fractures between July 1986 and June 1992. RESULTS: Fourteen children had fractures of the orbital roof, 10 children had fractures of the orbital floor, 14 children had mixed fractures, and two children had fractures of the medial wall. The mean age (4.8 +/- 3.3 years) of the 14 patients with roof fractures was significantly less than the mean age (12.0 +/- 4.2 years) of the 26 children with other orbital fractures. Logistic regression demonstrated that the age at which the probability of lower orbital fractures exceeds the probability of orbital roof fractures is 7.1 +/- 1.0 years. Orbital roof fractures had a significantly greater likelihood of associated neurocranial injuries. The need for surgical repair was significantly lower among children with roof fractures as well as among children 7 years of age and younger. CONCLUSIONS: Orbital roof fractures are a type of skull fracture that occur primarily in younger children as a consequence of the proportionally larger cranium and the lack of frontal sinus pneumatization. Lower orbital fractures are a type of facial fracture that occur primarily in older children as a consequence of the increased vulnerability of the face due to growth and the pneumatization of the paranasal sinuses.

Acoustic features of normal-hearing pre-term infant cry.

Acoustic features of expiratory cry vocalizations were studied in 125 pre-term infants prior to being discharged from a level-3 neonatal intensive care unit. The purpose was to describe various phonatory behaviors in infants in whom significant hearing loss could be ruled out. We also compared these results with normal-hearing full-term infants, and evaluated whether linkage exists among acoustic cry features and various anthropometric, diagnostic and treatment variables obtained throughout the peri- and neonatal periods. Our analysis revealed that cry duration was significantly related to total days receiving respiratory assistance. The occurrence of other complex spectral and temporal aspects of acoustic cry vocalizations including harmonic doubling and vibrato also increased in infants receiving some form of respiratory assistance. The presence of harmonic doubling also depended on weight and conceptional age at test. The discussion focuses on the implication of these relationships and directions for future research.

Rigid fixation of facial fractures in children.

This article presents a retrospective analysis of a selective use of rigid fixation among 62 children with facial fractures, treated at a Level I trauma center over a 5-year period (1986-1991). There were 21 mandible fractures, 11 orbital fractures, 11 zygomaticomalar complex fractures, 7 nasal fractures, 5 maxillary fractures, 3 pan-facial fractures, 2 nasal-orbital-ethmoidal complex fractures, and 2 frontal sinus fractures. Only 18 children had rigid fixation of their injuries. Complications of Le Fort upper facial fractures repaired with rigid fixation involved perioperative sinusitis; one case required oral antibiotics, the other ethmoidectomy and maxillary antrostomy. One child with a Le Fort fracture had delayed exposure of a zygomaticomalar buttress plate, which required surgical removal. Permanent enophthalmos occurred in two children with Le Fort fractures. The authors conclude that traditional conservative management is appropriate in most cases. However, in children aged 13 and older with mandible fractures and children with complex mid- and upper facial fractures, a judicious use of rigid fixation has advantages over the traditional techniques.

Treatment of experimental frostbite with pentoxifylline and aloe vera cream.

OBJECTIVE: To compare the therapeutic effects of systemic pentoxifylline and topical aloe vera cream in the treatment of frostbite. DESIGN: The frostbitten ears of 10 New Zealand white rabbits were assigned to one of four treatment groups: untreated controls, those treated with aloe vera cream, those treated with pentoxifylline, and those treated with aloe vera cream and pentoxifylline. MAIN OUTCOME MEASURES: Tissue survival was calculated as the percent of total frostbite area that remained after 2 weeks. RESULTS: The control group had a 6% tissue survival. Tissue survival was notably improved with pentoxifylline (20%), better with aloe vera cream (24%), and the best with the combination therapy (30%). CONCLUSION: Pentoxifylline is as effective as aloe vera cream in improving tissue survival after frostbite injury.