Pathologic characteristics of resected squamous cell carcinoma of the trachea: prognostic factors based on an analysis of 59 cases

While squamous cell carcinoma (SCC) is the most common tracheal malignancy, few reports describe the pathologic considerations that may guide intraoperative decisions and prognostic assessment. We reviewed 59 tracheal SCC treated between 1985 and 2008 by segmental resection of the trachea, including resection of the carina in 24% and inferior larynx in 14%. We classified these tumors by grading histologic differentiation and microscopic features used in SCC of other sites. Of 59 tumors, 24% (14 of 59) were well differentiated, 49% (29 of 59) were moderately differentiated, and 27% (16 of 59) were poorly differentiated. Unfavorable prognostic factors were tumor extension into the thyroid gland (all of five so-afflicted patients died of tumor progression within 3 years) and lymphatic invasion (mean survival 4.6 versus 7.6 years). Keratinization, dyskeratosis, acantholysis, necrosis, and tumor thickness did not predict prognosis. As surgical resection is the only curative treatment; the surgeon should establish clean lines of resection using, as appropriate, intraoperative frozen section. The pathologist can provide additional important prognostic information, including tumor differentiation and extent, invasion of surgical margins, and extension into the thyroid

Candida esophageal perforation and esophagopleural fistula: a case report

<p>Abstract</p> <p>Introduction</p> <p>Esophageal perforation is a rare disease, which can lead to significant morbidity and mortality. Its clinical presentation can mimic other disease processes and, therefore, it can be easily misdiagnosed. <it>Candida </it>infection of the esophagus is an extremely rare cause of esophageal perforation.</p> <p>Case presentation</p> <p>We report the youngest pediatric case in the medical literature of spontaneous esophageal perforation and an esophagopleural fistula due to <it>Candida </it>infection.</p> <p>Conclusion</p> <p>A high index of suspicion, especially in the presence of <it>Candida </it>empyema and the absence of disseminated infection, should raise the possibility of esophageal perforation with esophagopleural fistula formation. This can lead to early diagnosis and surgical intervention, which would decrease the high mortality rate of this rare condition.</p

Haptic adaptation to slant: No transfer between exploration modes

Human touch is an inherently active sense: to estimate an object’s shape humans often move their hand across its surface. This way the object is sampled both in a serial (sampling different parts of the object across time) and parallel fashion (sampling using different parts of the hand simultaneously). Both the serial (moving a single finger) and parallel (static contact with the entire hand) exploration modes provide reliable and similar global shape information, suggesting the possibility that this information is shared early in the sensory cortex. In contrast, we here show the opposite. Using an adaptation-and-transfer paradigm, a change in haptic perception was induced by slant-adaptation using either the serial or parallel exploration mode. A unified shape-based coding would predict that this would equally affect perception using other exploration modes. However, we found that adaptation-induced perceptual changes did not transfer between exploration modes. Instead, serial and parallel exploration components adapted simultaneously, but to different kinaesthetic aspects of exploration behaviour rather than object-shape per se. These results indicate that a potential combination of information from different exploration modes can only occur at down-stream cortical processing stages, at which adaptation is no longer effective

Physiological characteristics of dysphagia following thermal burn injury

The study aim was to document the acute physiological characteristics of swallowing impairment following thermal burn injury. A series of 19 participants admitted to a specialised burn centre with thermal burn injury were identified with suspected aspiration risk by a clinical swallow examination (CSE) conducted by a speech-language pathologist and referred to the study. Once medically stable, each then underwent more detailed assessment using both a CSE and fiberoptic evaluation of swallowing (FEES). FEES confirmed six individuals (32%) had no aspiration risk and were excluded from further analyses. Of the remaining 13, CSE confirmed that two had specific oral-phase deficits due to orofacial scarring and contractures, and all 13 had generalised oromotor weakness. FEES revealed numerous pharyngeal-phase deficits, with the major findings evident in greater than 50% being impaired secretion management, laryngotracheal edema, delayed swallow initiation, impaired sensation, inadequate movement of structures within the hypopharynx and larynx, and diffuse pharyngeal residue. Penetration and/or aspiration occurred in 83% (n = 10/12) of thin fluids trials, with a lack of response to the penetration/aspiration noted in 50% (n = 6/12 penetration aspiration events) of the cases. Most events occurred post swallow. Findings support the fact that individuals with dysphagia post thermal burn present with multiple risk factors for aspiration that appear predominantly related to generalised weakness and inefficiency and further impacted by edema and sensory impairments. Generalised oromotor weakness and orofacial contractures (when present) impact oral-stage swallow function. This study has identified a range of factors that may contribute to both oral- and pharyngeal-stage dysfunction in this clinical population and has highlighted the importance of using a combination of clinical and instrumental assessments to fully understand the influence of burn injury on oral intake and swallowing

A Controversy That Has Been Tough to Swallow: Is the Treatment of Achalasia Now Digested?

Esophageal achalasia is a rare neurodegenerative disease of the esophagus and the lower esophageal sphincter that presents within a spectrum of disease severity related to progressive pathological changes, most commonly resulting in dysphagia. The pathophysiology of achalasia is still incompletely understood, but recent evidence suggests that degeneration of the postganglionic inhibitory nerves of the myenteric plexus could be due to an infectious or autoimmune mechanism, and nitric oxide is the neurotransmitter affected. Current treatment of achalasia is directed at palliation of symptoms. Therapies include pharmacological therapy, endoscopic injection of botulinum toxin, endoscopic dilation, and surgery. Until the late 1980s, endoscopic dilation was the first line of therapy. The advent of safe and effective minimally invasive surgical techniques in the early 1990s paved the way for the introduction of laparoscopic myotomy. This review will discuss the most up-to-date information regarding the pathophysiology, diagnosis, and treatment of achalasia, including a historical perspective. The laparoscopic Heller myotomy with partial fundoplication performed at an experienced center is currently the first line of therapy because it offers a low complication rate, the most durable symptom relief, and the lowest incidence of postoperative gastroesophageal reflux

Perceiving Complex Objects: A Comparison of the Visual and the Haptic Modalities

Das wichtigste Werkzeug des Menschen sind seine Hände. Obwohl dieses Sprichwort schon sehr alt ist, ist nur wenig darüber bekannt, wie und was der Mensch wahrnimmt, wenn er Objekte in die Hand nimmt und betastet. Wie wird die ertastete Form eines Objektes im Gehirn abgespeichert? Ist die haptische Repräsentation ähnlich zu der, der visuellen Wahrnehmung? Entsteht sogar eine multisensorische, und somit gemeinsame, Repräsentation? Diese fundamentalen Fragen bilden den Hintergrund der vorliegenden Dissertation. Die hier dargestellten Experimente zeigen, dass der Mensch sehr ähnliche perzeptuelle Räume generiert, wenn komplexe Formen eines parametrisch definierten Objektraumes visuell oder haptisch exploriert werden. Um dies zu zeigen, wurde zuerst ein dreidimensionaler Objektraum muschelähnlicher Objekte generiert, welche in drei Formparametern variieren. Versuchspersonen wurden in den visuellen Versuchen Fotos oder virtuelle Rekonstruktionen der Objekte gezeigt, während in den haptischen Versuchen 3D Plastikmodelle der Objekte, generiert mit einem 3D Drucker, mit verbundenen Augen betastet wurden. In einer ersten Reihe von Experimenten bewerteten die Versuchspersonen die Ähnlichkeit zweier, nacheinander gezeigter, Objekte. Mit diesen Ähnlichkeitsbewertungen und mit Hilfe des Verfahrens der multidimensionalen Skalierung wurden die perzeptuellen Räume beider Modalitäten visualisiert. Überraschenderweise konnten die Versuchspersonen die Topologie des Objektraumes korrekt nachbilden, unabhängig davon, ob sie die Objekte gesehen oder betastet hatten. Weiterhin zeigten die Ergebnisse, dass der visuelle und der haptische perzeptuelle Raum fast identisch waren. Als nächstes wurden drei Kategorisierungsexperimente durchgeführt. Obwohl Kategorisierung allein durch den Tastsinn eher eine ungewöhnliche Aufgabe ist, konnte sie genauso gut gelöst werden, wie wenn die Versuchspersonen die Objekte sehen konnten. Anschließend wurden die perzeptuellen Räume beider Modalitäten mit den Ergebnissen der Kategorisierungsexperimente verglichen. Für alle Kategorisierungsexperimente und für beide Modalitäten war die wahrgenommene Ähnlichkeit zwischen Objekten einer Kategorie höher, als die Ähnlichkeit zweier Objekte aus unterschiedlichen Kategorien. Das heißt, dass, sowohl visuell als auch haptisch, Objekte in einer Kategorie zusammengruppiert wurden, die als sehr ähnlich wahrgenommen wurden. Um zu untersuchen, inwieweit die auf den computergenerierten Objekten basierenden Ergebnisse auf natürliche Objekte übertragbar sind, wurde eine Sammlung von Muscheln und Salzwasserschnecken erstellt. Mit diesen wurden, wie oben beschrieben, Ähnlichkeitsbewertungen durchgeführt und mittels multidimensionaler Skalierung die perzeptuellen Räume visualisiert. Wiederum waren der visuelle und der haptische perzeptuelle Raum fast identisch. Interessanterweise konnte man in beiden Räumen eine Gruppenbildung erkennen, weshalb auch hier drei Kategorisierungsexperimente durchgeführt wurden. Obwohl die Muscheln in einer Vielzahl an Objektmerkmalen variierten, z.B. Form, Farbe, Muster etc., konnten die Versuchspersonen diese Aufgabe ohne Mühe lösen, auch wenn sie die Objekte nur betasten durften. Zusätzlich konnte die Gruppenbildung, die schon in den perzeptuellen Räumen erkennbar war, die Kategorisierungsergebnisse richtig vorhersagen. Zusammengenommen weisen diese Ergebnisse darauf hin, dass die visuelle und die haptische Repräsentation von Objekten sehr eng miteinander verknüpft sein müssen. Zusätzlich liefern die Experimente Hinweise darauf, dass die gleichen Prozesse genutzt werden, wenn Ähnlichkeiten zwischen Objekten wahrgenommen werden, oder Objekte kategorisiert werden, egal ob die Objekte visuell oder haptisch exploriert werden

Integrating Visual and Haptic Shape Information to Form a Multimodal Perceptual Space

In this study we want to address the question to what extent the visual and the haptic modalities contribute to the final formation of a complex multisensory perceptual space. By varying three shape parameters a physical shape space of shell-like objects was generated. Participants were allowed to either see or touch the objects or use both senses to explore the objects. Similarity ratings were performed and analyzed using multidimensional scaling (MDS) techniques. By comparing the unimodal perceptual spaces to the multimodal perceptual space we tried to resolve the impact of the visual and the haptic modalities on the combined percept. We found that neither the visual nor the haptic modality dominated the final percept, but rather that the two modalities contributed to the combined percept almost equally. To investigate to which degree these results are transferrable to natural objects, we performed the same visual, haptic, and visuo-haptic similarity ratings and multidimensional scaling analyses using a set of natural sea shells. Again, we found almost equal contributions of the visual and the haptic modalities to the combined percept. Our results suggest that multisensory perceptual spaces are based on a complex combination of object information gathered by different senses

Perceptual representations of parametrically-defined and natural objects comparing vision and haptics

Studies concerning how the brain might represent objects by means of a perceptual space have primarily focused on the visual domain. Here we want to show that the haptic modality can equally well recover the underlying structure of a physical object space, forming a perceptual space that is highly congruent to the visual perceptual space. By varying three shape parameters a physical shape space of shell-like objects was generated. Sighted participants explored pictures of the objects while blindfolded participants haptically explored 3D printouts of the objects. Similarity ratings were performed and analyzed using multidimensional scaling (MDS) techniques. Visual and haptic similarity ratings highly correlated and resulted in very similar visual and haptic MDS maps. To investigate to which degree these results are transferrable to natural objects, we performed the same visual and haptic similarity ratings and multidimensional scaling analyses using a set of natural sea shells. Again, we found very similar per ceptual spaces in the haptic and visual domain. Our results suggest that the haptic modality is capable of surprisingly acute processing of complex shape