Multi-channel cochlear implant histopathology: are fewer spiral ganglion cells really related to better clinical performance?

CONCLUSION: Our findings show that all cochlear implanted temporal bones had a varied degree of trauma and inflammatory reaction from cochlear implantation. No definitive relationship was observed from our limited number of specimens between residual spiral ganglion cells (SGCs) in implanted temporal bones and clinical speech performance. OBJECTIVES: We hypothesize that there is a relationship between residual SGCs in cochlear implanted temporal bones and clinical speech performance. Our aim was to examine the histopathology of multi-channel cochlear implant temporal bones and to evaluate the relationship of residual SGC counts to clinical hearing performance. METHODS: Temporal bones from four cochlear implant patients were examined histologically. Comparisons were made between implanted and nonimplanted temporal bones. Clinical performance data were obtained from patient charts. RESULTS: There were varying amounts of inflammation in the basal turn of the cochleae in all four implanted temporal bones. Trauma to the facial nerve at the facial recess was noticed in one case. Surviving dendrites varied from 5% to 30% among four cases, with no relationship to clinical performance. The speech recognition scores, measured with Central Institute of the Deaf (CID) sentence score, varied among patients from 4% to 89%, while the patient with the highest SGCs had the best clinical outcome.

An unusual case of a ballpoint pen migrating into the parapharyngeal space and middle mediastinum.

Foreign bodies that penetrate the esophagus and migrate extraluminally are unusual. If they are left untreated, serious complications arise from mediastinitis, and damage to the major structures in the neck can occur. We report a case of a patient who presented with chest pain on inspiration that was found to be caused by a foreign body in the parapharyngeal space and middle mediastinum. Preoperative imaging is critical in obtaining landmarks for safe surgical exploration and is essential to the successful management of penetrating and migrating foreign bodies. This case highlights the importance of localizing the foreign body preoperatively to aid in its surgical removal via a transcervical approach.

Congenital cholesteatoma involving the Eustachian tube.

Cholesteatomas, classified as acquired or congenital, are non-neoplastic, keratinizing squamous epithelial lesions that can affect many different areas of the temporal bone. We present a case of a six-month-old female with chronic otorrhea who was found to have a congenital cholesteatoma originating from the Eustachian tube. Chronic pressure from cholesteatoma expansion turned the Eustachian tube into a large cavity approximately double the size of the middle ear space. This case was unusual not only in the location of the cholesteatoma but also in respect to the unusual presentation of chronic middle ear infection due to Eustachian tube obstruction.

Informed consent process and patient communication after complications in sinus surgery.

Sinonasal surgery has always been a potential source of complications. Most legal suits involving endoscopic sinus surgery alleged lack of informed consent. In this article, the authors discuss what informed consent means, to the physician and the patient, and how it is relevant in the case of complications. They also explain that patient communication is important and helps to develop a positive physician-patient relationship.

Minimally invasive video-assisted thyroidectomy: a retrospective study over two years of experience.

OBJECTIVE: The minimally invasive video-assisted thyroidectomy technique has slowly gained acceptance. Previous studies have reported advantages of better cosmetic results and faster postoperative recovery. We report preliminary results from our single assistant technique over the initial two years of inception at an academic training center. METHODS: This study consists of a retrospective chart review of 172 cases between May 2005 and September 2007. All cases started as video-assisted thyroidectomy were included. Demographic, pre- and postoperative clinical data, imaging results, and hospital stay were collected. RESULTS: Acceptable data were available for 24 male and 148 female patients who underwent the video-assisted procedure. Five cases were converted to the conventional thyroidectomy. Of the 172 cases, 60 total thyroidectomies and 112 hemithyroidectomies were performed, with 37 cases of malignancy. The average hospitalization was 1.43 days with mean incision length was 3.51 cm, mean surgical time of 91.37 minutes, and mean blood loss of 31 cc. Transient voice problems were noted in 10 patients. CONCLUSION: We found statistically improved operative times, hospital stay, and blood loss the first 2 years with a low rate of temporary complications. It appears that minimally invasive video-assisted thyroidectomy is a safe and feasible option to standard thyroidectomy in selected patients.

Multi-modal magnetic resonance imaging alterations in two rat models of mild neurotrauma.

Magnetic resonance imaging (MRI) is increasingly used in the assessment of the severity and progression of neurotrauma. We evaluated temporal and regional changes after mild fluid percussion (FPI) and controlled cortical impact (CCI) injury using T2-weighted-imaging (T2WI) and diffusion-weighted imaging (DWI) MRI over 7 days. Region of interest analysis of brain areas distant to the injury site (such as the hippocampus, retrosplenial and piriform cortices, and the thalamus) was undertaken. In the hippocampus of CCI animals, we found a slow increase (51%) in apparent diffusion coefficients (ADC) over 72 h, which returned to control values. The hippocampal T2 values in the CCI animals were elevated by 18% over the 7-day time course compared to control, indicative of edema formation. Histological analysis supported the lack of overt cellular loss in most brain regions after mild CCI injury. FPI animals showed a generalized decrease in hippocampal ADC values over the first 72 h, which then returned to sham levels, with decreased T2 values over the same period, which remained depressed at 7 days. Histological assessment of FPI animals revealed numerous shrunken cells in the hippocampus and thalamus, but other regions showed little damage. Increased immunohistochemical staining for microglia and astroglia at 7 days post-injury was greater in FPI animals within the affected brain regions. In summary, traumatic brain injury is less severe in mild CCI than FPI, based on the temporal events assessed with MRI.

Regional dissection and determination of loosely bound and non-heme iron in the developing mouse brain.

Iron is a trace metal essential for normal brain development but toxic in excess as it is capable of generating highly reactive radicals that damage cells and tissue. Iron is stringently regulated by the iron regulatory proteins, IRP1 and IRP2, which regulate proteins involved in iron homeostasis at the posttranscriptional level. In this study, 12 distinct regions were microdissected from the mouse brain and regional changes in the levels of loosely bound and non-heme iron that occur with development were measured. We examined 6, 12, and 24 week old wildtype C57BL/6 mice and mice with a targeted deletion of iron regulatory protein 2 (IRP2-/-) that have been reported to develop neurodegenerative symptoms in adulthood. In wildtype mice, levels of loosely bound iron decreased while non-heme iron increased with development. In contrast, an increase in loosely bound and a more pronounced increase in non-heme iron was seen in IRP2-/- mice between 6 and 12 weeks of age, stemming from lower levels at 6 weeks (the youngest age examined) compared to wildtype. These results have implications for understanding the increase in regional brain iron that is associated with normal aging and is postulated to be exacerbated in neurodegenerative disorders.