To determine whether aggressive surgical management is more effective than local canal resection (LCR) for early-stage temporal bone malignancies.Retrospective study.Forty-three cases of early-stage external auditory canal (EAC) carcinoma who received surgical management between 1993 and 2011 were reviewed. Preoperative computed tomography, enhanced magnetic resonance imaging, pure-tone audiometry, and biopsy were performed. Patients underwent either LCR or lateral temporal bone resection (LTBR). Postoperative pathologic examinations were conducted on all specimens, including assessment of margin status. The duration of the postoperative follow-up period ranged from 6 months to 18 years.Of 26 patients who underwent LCR, 10 were stage T1 and 16 were T2. Positive surgical margins were identified in 14 patients. During the follow-up, 12 patients developed recurrence. Of 17 patients who underwent LTBR with superficial parotidectomy, six were stage T1 and 11 were T2. The lateral EAC margins were negative in all 17 patients. In 2/6 T1 patients and in 5/11 T2 patients, tumor cells were identified deep within the EAC cartilage and parotid gland. All of the patients who underwent LTBR survived without evidence of recurrence.LTBR with superficial parotidectomy offers the greatest chance of cure for early-stage EAC carcinoma. Intraoperative frozen sections are necessary to determine the tumor-free lateral EAC margins. Postoperative radiotherapy is not strongly recommended for early-stage EAC carcinoma after LTBR.
The relation between iron deficiency (ID) and sudden sensorineural hearing loss (SSHL) was evaluated in the growing rats of three different experimental groups. Fourteen rats of 132 (10.61%) that were raised on a basic ID diet showed SSHL in varied extent, from moderate to profound. By contrast, none of 128 standard control and 126 anemic control rats that were fed with the final iron-supplemented diet showed any degree of SSHL. The main cochlear correlates of SSHL in ID rats were synchronous abnormalities of the iron-containing enzymatic activity in the whole cochlea, a significant reduction of spiral ganglion cells and a rapid involvement of stereocilia of the outer and inner hair cells. The results suggest that ID can play a major role in the pathogenesis of SSHL.
Objective To establish a precise three-dimensional model of membranous labyrinth for further morphologic investigation and physiological research. Methods Complete series of serial unstained celloidin sections of a fresh human temporal bone were taken photos by high-pixel digital camera. The images were then processed with the technique of photo stitch and employed to reconstruct the three-dimensional model of the membranous labyrinth using the method of surface rendering. Results In 3D-Doctor software, the model was displayed by different methods. The model was also exported to VRML format and their virtual visualization was realized through the software of Cortona virtual reality modeling language viewer. Conclusions Precise modeling of membranous labyrinth could be realized by advanced imaging technique. With the advanced virtual reality software and equipments, the virtual visualization of membranous labyrinth could be realized, which would benefit the morphologic investigation and education.
Key words:
Imaging,three-dimensional; Ear,inner; celloidin; Computer simulation
To investigate regeneration of the distal facial nerve following nerve grafting within the tympanic segment with geniculate ganglion preservation or dissection.
Design
Randomized controlled trial.
Subjects
Twenty-three adult New Zealand albino rabbits were used in this study.
Interventions
A 2-mm tympanic segment of the facial nerve was removed, and the greater auricular nerve was harvested for grafting in all animals. In group 1 (10 rabbits), the geniculate ganglion was preserved. In group 2 (13 rabbits), the geniculate ganglion was dissected. Mastoidal and extratemporal segments of the facial nerve were harvested 3 months postoperatively for histological examination by electron microscopy.
Results
The number of myelinated axons in normal facial nerves was 1819.6 ± 535.6. In group 1, the number of myelinated axons was 123.6 ± 31.1, and, compared with normal facial nerves, the diameter of the regenerative axons was decreased and the sheath thickness in the regenerative fiber was diminished. In group 2, the number of myelinated axons was 515.1 ± 103.1, while the myelin sheath thickness was proportionate to axon diameter. (Data are given as mean ± SD.)
Conclusion
Geniculate ganglionectomy may improve motor axon regeneration.
To explore whether there could be proliferative cells in the cochlea of the newborn rat or not and what kinds of cells should be differentiated from the proliferative cells while to study the effect of the growth factors on the proliferative cells and the ultrastructure of the proliferative cells.The Corti's organ were dissected from the cochlea of newborn SD rats and cultured. The proliferative condition of cells was tested by infusing the 5-bromo-2-deoxyuridine (BrdU) into the culture medium. And the variety of the spheres and differentiated cells were identified by immunohistochemistry. Corti's organ from forty-eight surface preparations was randomly divided into 4 groups: control group; epidermal growth factor (EGF) group; basic fibroblast growth factor (bFGF) group and EGF + bFGF group, with each group including 12 Corti's organ, and then the number of cell spheres of each Corti's organ was counted. The data was statistically analysed with ANOVE. Finally, the proliferative cells were observed under scanning electron microscope and transmission electron microscope.(1) The cell spheres can be observed in the cell culture of the Corti's organ. In present experiment, 90.1% of cells in spheres were labeled by BrdU, while nestin of spheres, the marker of hair cells--myosin 7A, espin, and phalloidin of the differentiated cells were positive. The marker of neuron-microfilament-M was also positive, and some differentiated cells were labeled by myosin 7A and BrdU, espin and BrdU, NF-M and BrdU at the same time. (2) The average number (x +/- s) of spheres from single Corti's organ was: 45.3 +/- 23.00 in control group, 86.2 +/- 34.1 in EGF group, 96.5 +/- 33.6 in bFGF group and 131.2 +/- 47.00 in EGF + bFGF group. There were significant differences between other groups respectively (P < 0.05) but there was no significant differences between EGF group and bFGF group (P > 0.05). (3) Scanning electron microscopy and transmission electron microscopy showed that cells of the spheres were round and had the same size and many short and thin microvilli on the surface of these cells. The cytoplasm were rich of organellae such as endoplasmic reticulum, mitochondrion, and cytoskeleton such as microfilament, microtube, et al. Tight junction, desmosomes and gap junctions between two adjacent cells were seen.The proliferative cells are observed in the cochlea of the newborn rats and proliferative cells could differentiated into hair cells with bundles-like structure and neuron. Both EGF and bFGF possess the promoting effects for proliferation on the proliferative cells while the proliferative cells have characters of earlier immature cells.
To objectively evaluate the usefulness and the reliability of the perineural vascular plexus as a landmark for facial nerve as well as whether it will be a landmark for identification of the facial nerve in surgery for otology and neurotology by means of investigating the location of the facial nerve for prevention of iatrogenic facial palsy.Prospective case series were designed. Three hundred and eleven consecutive patients were studied which required tympanoplasty for chronic otitis media or microsurgery for facial nerve decompression and congenitally malformation of the ear from July 2002 to July 2005. All the patients were operated by the first author. Perineural vascular plexus as a landmark for identification of the facial nerve in surgery were observed to assess the utility.The well recognized perineural vascular plexus were seen on the horizontal mesotympanic segment of the nerve in 95.8% of patients (298 cases), and only in 4.2% of the patients (13 cases), the vessel plexus was difficult to identify. The 95% confidence interval was from 93.6% to 98.0%.The vascular plexuses around or over the horizontal portion of the facial nerve provide an early and direct indicator of the location of the facial nerve. The perineural vascular plexus could be a dependable and reliable landmark for the identification the horizontal part of the facial nerve in surgery for otology and neurotology.
Nowadays, the call for enterprise innovation is becoming increasingly urgent. There is also continued interest in how to make the best use of entrepreneurs' research experience. However, there are still differences in research results on the effect of entrepreneurs' research experience on enterprise innovation, and evidence from Micro, Small, and Medium Enterprises (MSMEs) is still insufficient. Drawing on the upper-echelon theory, imprinting theory, tacit knowledge, and institutional logic theory, we argue that the effect of an entrepreneur’s research experience on innovation could be the manifestation of established imprints in the current environment. Utilizing data from Chinese New OTC Market listed enterprises from 2008-2016, we find the career research imprint can spur enterprise innovation, while the postgrad research imprint cannot promote innovation alone. We also examine how governance structures moderate imprints’ effects. Finally, we reveal the preference for high-quality innovation of postgrad research imprints.
Solitary or isolated involvement of the sphenoid sinus (Isolated sphenoid sinus disease; ISSD ) is a relatively uncommon disease. The present study reviews retrospectively 125 patients with ISSD treated at the Departments of Otolaryngology, Eye Ear Nose and Throat Hospital, Shanghai Medical University (109), and Hyogo College of Medicine (16) over a period of 25 years. Diagnosis was made on the basis of history, signs, nasal endoscopy, imaging techniques with CT/MRI. The final diagnosis of ISSD was established after histopathological and microbiological examinations of the excisional specimen. The pathology was sphenoid sinusitis (40), sphenoid cysts (35), fungal diseases (19), malignant tumors (9), and others (20). The most common initial symptom was headache, followed by visual changes and cranial nerve palsies due to the nearby involvements. Increasing use of routine imaging techniques with CT/MRI and diagnostic nasal endoscopy resulted in the increased numbers of early ISSD. Recent nasal endoscopic ostial sphenoidotomy warrants for the precise pathological diagnosis, and at the same time for the safe and immediate treatment, prior to the sequential extension to adjacent vital structures even to the serious or fatal stage.
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