Faculty Bibliography

PURPOSE: Cesium-131 ((131)Cs) radioactive seed is Food and Drug Administration approved for permanent seed implant for all cancers, including lung and head and neck (HN) cancers. We describe the first clinical report of (131)Cs dosimetry and exposure rates to treating physicians and staff. METHODS AND MATERIALS: Twenty-eight patients received (131)Cs implant for early stage lung and recurrent HN cancers. A nomogram was developed to calculate the number of seeds needed to cover the wedge line with the prescription dose (80 Gy). Final dosimetry was obtained after CT planning a few days following the surgical procedure. Radiation exposure to the treating physicians and staff was measured at the completion of the procedure. RESULTS: A nomogram was developed using the variseed software with source data from American Association of Physicists in Medicine TG-43 report. The total volume covered by the prescription isodose line of (131)Cs was measured and compared with (125)I. The prescription volume was smaller for (131)Cs. In addition, the exposure rate with (131)Cs was found to be acceptable. CONCLUSION: Our preliminary experience with (131)Cs lung and HN brachytherapy has been very encouraging with excellent dosimetric coverage and acceptable exposure to the treating physicians and staff.

OBJECTIVE: To evaluate and compare image quality between flat-panel volumetric computed tomography (fpVCT) and multislice CT (msCT) in temporal bones with cochlear implants (CIs), and to evaluate fpVCT imaging for accuracy in determining CI electrode positioning. METHODS: Six cadaveric temporal bones were imaged prior to CI using fpVCT. Each bone was implanted with an electrode array and rescanned in order to create radial reformatted images through each electrode contact. Electrode-modiolar interval (EMI) distances were measured. The bones were fixed and cut in order to grossly evaluate for CI intrascalar positioning and insertional trauma. MAIN OUTCOME MEASURE: To compare image quality between fpVCT and msCT in temporal bones with CI, and to evaluate the utility of fpVCT in post-implantation temporal bone analysis. RESULTS: The mean EMI distances did not differ significantly between fpVCT and msCT images, while the image quality was significantly better for fpVCT. Furthermore, information about intracochlear trauma and intrascalar electrode array positioning can be ascertained using this radiographic technique. CONCLUSION: fpVCT and msCT do not differ significantly in the evaluation of EMI distances in implanted temporal bones, but the image quality is significantly better using fpVCT. Additionally, useful information regarding intracochlear trauma, electrode depth of insertion, and intrascalar positioning can be gained from fpVCT imaging. Given the ease of use, superior image quality, improved convenience, reduced levels of radiation, and agreement with histology, fpVCT is a valuable option for post-implantation temporal bone imaging

The central nervous system is plastic throughout life, but is most sensitive to the statistics of the sensory environment during critical periods of early postnatal development. In the auditory cortex, various forms of acoustic experience have been found to shape the formation of receptive fields and influence the overall rate of cortical organization. The synaptic mechanisms that control cortical receptive field plasticity are beginning to be described, particularly for frequency tuning in rodent primary auditory cortex. Inhibitory circuitry plays a major role in critical period regulation, and new evidence suggests that the formation of excitatory-inhibitory balance determines the duration of critical period plasticity for auditory cortical frequency tuning. Cortical inhibition is poorly tuned in the infant brain, but becomes co-tuned with excitation in an experience-dependent manner over the first postnatal month. We discuss evidence suggesting that this may be a general feature of the developing cortex, and describe the functional implications of such transient excitatory-inhibitory imbalance

BACKGROUND: We report a case of Rosai-Dorfman disease (RDD) presenting as an oropharyngeal mass, and we provide a detailed discussion of this rare clinical entity. METHODS: An initial biopsy, described as being consistent with lymphoma, was reviewed at a second outside institution and was thought to be reactive lymphoid hyperplasia. The patient then presented to our institution for a second opinion. Direct laryngoscopy revealed a firm 1- to 2-cm lesion involving the left soft palate and superior tonsillar pillar. RESULTS: The diagnosis of RDD was confirmed with immunohistochemical staining on both cytology and histology. The patient elected conservative management and has remained asymptomatic for over 15 months. CONCLUSION: The diagnosis of RDD may be challenging in cases presenting initially with extranodal disease. Close follow-up and repeat biopsies may be necessary. Identification of Rosai-Dorfman cells with emperipolesis and confirmation with appropriate immunohistochemical staining on both cytology and histology is diagnostic of RDD. Conservative treatment is appropriate in select cases.

Two former U.S. presidents, Ulysses S. Grant and Grover Cleveland, were diagnosed with head and neck cancer in 1884 and 1893, respectively. A historical review of the risk factors, diagnoses, and treatments is examined and compared with modern-day interpretations. A comparison was made using the original diagnoses with today's equivalent diagnosis. Different treatment outcomes at the time of the original diagnoses relative to today's treatment are reviewed. Clinicians must be familiar with risk factors, signs, symptoms, diagnosis, and treatment of head and neck cancer.