EFFECT OF AN ACUTE INCREASE IN CEREBROSPINAL FLUID PRESSURE ON LUNG COMPLIANCE IN THE RABBIT

Cerebrospinal fluid pressure (P_csf) was increased acutely bythe injection of normal saline into the cisterna magna of anaesthetizedrabbits to values which interrupted cerebral blood flow. Whenincreased P_csf was maintained for a minimum of 3 min, staticlung compliance decreased and lung weight (after sacrifice)increased without marked change in arterial blood-gas tensions.The magnitude of the increase in P_csf did not affect the changein compliance and weight. There was marked unexplained metabolicacidosis. The pulmonary findings may result from a massive shiftof blood from the systemic to the pulmonary circulation leadingto increased permeability of the inter-endothelial junctionsof the pulmonary capillaries.     

Unique characteristics of malignant schneiderian papilloma

PURPOSE: To ascertain the characteristics unique to malignant schneiderian papilloma (MSP). METHODS: A case-control study of all schneiderian papilloma (SP) patients treated between 1978 and 1997 was conducted. Comparison was made between patients with MSP and patients with benign SP (BSP). RESULTS: A diagnosis of SP was made in 72 patients. Malignant changes, all of them the inverted papilloma subtype, were found in 8 of these patients. Three were diagnosed carcinoma in situ, and 5 were defined as invasive squamous cell carcinoma. At presentation, the MSP patients had significantly larger tumor spread into the ethmoid and sphenoid sinuses. The recurrence rate was significantly lower in SP patients treated with extensive surgical procedures. An association was found between the presence of malignant lesions and positive smoking history, subjective awareness of a nasal mass, and ethmoid and sphenoid sinus involvement. Also, histologic multicentricity was a feature more often seen in MSP than BSP and was a significant correlate with malignancy. CONCLUSION: The physician evaluating a patient with SP should be aware of the features described and of their possible association with a malignant lesion.