Faculty Bibliography

BACKGROUND: Oncologic resection of the maxilla requires management of the nasolacrimal sac/duct system (NLS). A variety of techniques may be used: simple transection, transection with transcanalicular stenting, drilling of the entire nasolacrimal bony canal to the inferior meatus with mobilization of an intact NLS, marsupialization of the NLS with or without stenting, and simple transection with routine delayed dacryocystorhinostomy (DCR) for symptomatic epiphora. Rates of prolonged epiphora range from 13 to 63%. OBJECTIVES: We present our approach to NLS management during maxillectomy, and our rates of epiphora. STUDY DESIGN: Review of 212 consecutive patients who underwent transection of the NLS during medial maxillectomy, complete maxillectomy with preservation of orbital contents, suprastructure maxillectomy, or maxillectomy as part of anterior craniofacial resection. Patients with primary NLS tumors were excluded. Prolonged epiphora is defined as persistent if it lasts more than 6 months. METHODS: After exposure of the anterior maxillary wall and inferior and medial orbital rim, a high-speed drill and Kerrison rongeurs are used to remove the anterior wall of the nasolacrimal canal. The NLS is transected 12-15 mm distal to the periorbita and removed from the canal. Two 4-6-mm opposing incisions are made at the distal duct. Two semicircular flaps are everted, folded, and sutured to the proximal sac or periorbita. A transcanalicular stent is not placed. RESULTS: Two-hundred twelve patients underwent the above-mentioned procedure. Four patients (1.9%) developed prolonged epiphora, which required delayed DCR. CONCLUSIONS: Marsupialization of the NLS without stenting provided us with an acceptably low rate of prolonged epiphora

Interaction between an electronic and a biological circuit has been investigated for a pair of electrically connected nonlinear oscillators, with a spontaneously oscillating olivary neuron as the single-cell biological element. By varying the coupling strength between the oscillators, we observe a range of behaviors predicted by model calculations, including a reversible low-energy dissipation "amplitude death" where the oscillations in the coupled system cease entirely.

Survival analysis encompasses investigation of time to event data. In most clinical studies, estimating the cumulative incidence function (or the probability of experiencing an event by a given time) is of primary interest. When the data consist of patients who experience an event and censored individuals, a nonparametric estimate of the cumulative incidence can be obtained using the Kaplan-Meier method. Under this approach, the censoring mechanism is assumed to be noninformative. In other words, the survival time of an individual (or the time at which a subject experiences an event) is assumed to be independent of a mechanism that would cause the patient to be censored. Often times, a patient may experience an event other than the one of interest which alters the probability of experiencing the event of interest. Such events are known as competing risk events. In this setting, it would often be of interest to calculate the cumulative incidence of a specific event of interest. Any subject who does not experience the event of interest can be treated as censored. However, a patient experiencing a competing risk event is censored in an informative manner. Hence, the Kaplan-Meier estimation procedure may not be directly applicable. The cumulative incidence function for an event of interest must be calculated by appropriately accounting for the presence of competing risk events. In this paper, we illustrate nonparametric estimation of the cumulative incidence function for an event of interest in the presence of competing risk events using two published data sets. We compare the resulting estimates with those obtained using the Kaplan-Meier approach to demonstrate the importance of appropriately estimating the cumulative incidence of an event of interest in the presence of competing risk events

PURPOSE: Although an important risk factor for oral cancer is the presence of epithelial dysplasia, many lesions will not progress to malignancy. Matrix metalloproteinases (MMPs) are zinc-dependent proteinases capable of digesting various structural components of the extracellular matrix. Because MMPs are frequently overexpressed in oral squamous cell carcinoma (SCC), we hypothesized that they are also overexpressed in oral dysplasias; we also hypothesized that those dysplasias that progress to oral cancer express higher levels of MMPs than those lesions that do not progress. EXPERIMENTAL DESIGN: In this retrospective study, we examined changes in MMP-1, -2, and -9 mRNA expression using quantitative TaqMan reverse transcription-polymerase chain reaction in 34 routinely processed oral dysplasias and 15 SCCs obtained from 34 patients. After several years of close follow-up, 19 dysplasias progressed to oral SCC and 15 did not. RESULTS: Overall, MMP-1 mRNA was overexpressed (>2-fold) in 24 of 34 (71%) dysplasias and 13 of 15 (87%) oral SCCs. MMP-2 overexpression was seen in 11 of 34 (32%) dysplasias and 7 of 15 (47%) cancers; for MMP-9, overexpression was identified in 29 of 34 (85%) dysplasias and 15 of 15 (100%) cancers. MMP-1 and -9 levels were significantly higher in the SCCs compared with all oral dysplasias (P = 0.004 and P = 0.01, respectively). MMP-1 and -9 mRNA levels were significantly higher in the oral dysplasias that progressed to oral cancer compared with those that did not (P = 0.04 and P = 0.002, respectively). CONCLUSIONS: Levels of MMP-1 and -9 mRNA may be markers of malignant transformation of oral dysplasia to oral cancer

PURPOSE: Present a case of bilateral foveal acute myelogenous leukemic tumors that responded to radiation therapy. DESIGN: Case report. METHODS: A patient was diagnosed with bilateral subfoveal infiltration of known systemic acute myelogenous leukemia. He received a standard induction chemotherapy, followed by consolidation therapy for his systemic leukemia. However, despite a complete marrow response, the intraocular tumors did not regress. Therefore, he was given low dose (1950-cGy) ocular external beam radiation therapy. RESULTS: One course of systemic cytarabine chemotherapy failed to control the subfoveal tumors, leaving the patient at risk for permanent vision loss. In contrast, external beam radiation therapy improved his vision from 20/60 in his right eye to 20/20 and from 20/70 in his left eye to 20/25. CONCLUSION: Although systemic chemotherapy can be used to treat intraocular metastasis, external beam radiation may provide more prompt resolution of vision-threatening tumors

OBJECTIVE: To assess the event rate of myringotomy and tube placement (M&T) in the pediatric patient population with sickle cell disease (SCD). METHODS: Four hundred and forty-nine children with confirmed SCD have been followed over a period of 11.5 years at two hospital-based pediatric hematology and otolaryngology offices, and three tertiary care hospitals. Children with SCD who had undergone M&T were identified via computer search of International Classification of Diseases codes by the medical records departments of the three hospitals, and from two databases of the hematology offices. The inpatient and outpatient medical records of all children identified were reviewed. RESULTS: For the 449 patients, mean duration of SCD follow-up was 6.13 +/- 3.36 years. Of these, eight patients (four boys, four girls, mean age 9 +/- 3.5 years; four patients had hemoglobin SC disease, and four patients had sickle cell anemia type SS) underwent M&T. Two children met criteria for severe SCD. The event rate for M&T insertion was 0.29/100 person-years, 95% CI (0.15, 0.58). CONCLUSIONS: The event rate for M&T in children with SCD, compared to a historical control group, is lower than that of the general population. Type and severity of SCD were not predictive of the need for tube insertion. Children with sickle cell disease do not have an increased rate of M&T insertion