Biomedical subjects

S T Phan

Publications and source records attributed to S T Phan.

3 recordsLinked to original sources

PubMed2003

Bilateral diffuse lamellar keratitis following bilateral simultaneous versus sequential laser in situ keratomileusis.

AIM: To determine the difference in the incidence of bilateral diffuse lamellar keratitis (DLK) in patients undergoing simultaneous versus sequential laser in situ keratomileusis (LASIK) as an indication of intrinsic risk for inflammation. METHODS: A retrospective non-comparative case series of 1632 eyes that had undergone bilateral, simultaneous or sequential LASIK between April 1998 and February 2001 at a university based refractive centre by three surgeons. All cases that developed clinically evident DLK were identified and reviewed. In order to identify isolated cases and exclude those caused by environmental factors, when more than one patient in a given session developed DLK, the session was excluded. The main outcome measure was the incidence of unilateral and bilateral isolated, non-epidemic DLK. RESULTS: Of 1632 eyes, 126 eyes (7.7%) of 107 patients developed at least grade 1 DLK. In six operating sessions, DLK was observed in more than one patient per session, and on this basis 13 patients were excluded. 16 of the 94 remaining patients developed DLK in both eyes (17.0%). Six of 41 patients (14.6%) in the simultaneous group, versus 10 of 53 patients (18.9%) in the sequential group developed bilateral DLK (p >0.5). CONCLUSION: In isolated, non-epidemic bilateral DLK, a similar incidence was observed regardless of whether the surgery was simultaneous or sequential, suggesting an underlying intrinsic cause for DLK.

Humans↗

PubMed1997

Collision tumor: a peripheral neuroepithelioma and a transitional-cell carcinoma occurring simultaneously in the renal pelvis.

We report a unique case of a collision tumor of the kidney composed of a peripheral neuroepithelioma (PNE) and a transitional cell carcinoma (TCC) that occurred in a 67-year-old man with a long history of superficial TCC of both the bladder and bilateral upper urinary tracts. The PNE was composed of hyperchromatic, small, round cells, arranged in clusters and poorly cohesive sheets. Immunohistochemical studies revealed the small cells to be strongly positive for O13 (ie, a MIC2 gene product stain [CD99]) and vimentin. Electron microscopic examination found numerous interdigitating cell processes, multiple poorly formed cell-cell junctions, and dense-core granules. The latter were most conspicuous at the tips of the cell precesses. The PNE cells were clearly negative for cytokeratin, and they showed no transitional or intermediate features that would suggest evolution of the PNE from the adjacent TCC. The proximity of these two tumors appears to be serendipitous; thus, it can be considered a true collision tumor of the kidney.

12E7 Antigen↗

PubMed1996

Effects of a combination of detomidine and butorphanol on respiratory function in horses with or without chronic obstructive pulmonary disease.

OBJECTIVE: To evaluate the effects of detomidine and butorphanol in combination on respiratory function in horses and to determine whether these effects are more severe in horses with pre-existing respiratory dysfunction, DESIGN: Pulmonary function testing and arterial blood gas analyses were performed before and after administration of a combination of detomidine (10 micrograms/kg of body weight, i.v.) and butorphanol (20 micrograms/kg, i.v.). ANIMALS: 5 horses with chronic obstructive pulmonary disease and 5 horses free of respiratory disease (controls). PROCEDURES: Flow rates were obtained from a pneumotachograph attached to a face mask, and esophageal pressure was measured with a catheter placed in the distal third of the esophagus. Respiratory rate, tidal volume (VT), minute ventilation (VE), maximal change in transpulmonary pressure, pulmonary resistance, and dynamic compliance were calculated by use of a pulmonary function computer. Arterial blood was collected from the transverse facial artery, and blood gas partial pressures were measured with an automated blood gas analyzer. RESULTS: The combination of detomidine and butorphanol caused significant changes with time in respiratory rate, VT, VE, PaO2, and PaCO2. Changes with time in VT, VE, and maximal change in transpulmonary pressure were significantly different between groups. CONCLUSION: The combination of detomidine and butorphanol affects respiratory function in horses, and the observed changes are affected by the presence of pre-existing respiratory dysfunction. CLINICAL RELEVANCE: Changes in respiratory function after administration of a combination of detomidine and butorphanol are not necessarily more severe in horses with pre-existing respiratory dysfunction.

Airway Resistance↗