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S Doshi

Publications and source records attributed to S Doshi.

8 recordsLinked to original sources
PubMed1999

Coronary pseudo-lesions induced in the left anterior descending and right coronary artery by the angioplasty guide-wire.

New lesions appearing during coronary angioplasty may be due to a number of causes including spasm, dissection, embolisation, thrombosis and creation of a pseudo-lesion. The term "coronary pseudo-lesions" has been given to describe artefactual lesions occurring during percutaneous transluminal coronary angioplasty and induced by the angioplasty guide-wire and/or balloon as a result of straightening of the vessel's curvature. No specific treatment is required as they resolve completely on removal of the angioplasty wire. Few modern texts of interventional cardiology contain description of this important phenomenon and we suspect that they pass largely unrecognised. All angioplasty operators should become familiar with this complication as failure to do so may lead to inappropriate intervention with attendant increase in risk to the patient. We report three cases of coronary pseudo-lesion. In two cases affecting the right coronary artery and in the third the left anterior descending coronary artery. Pseudo-lesions affecting the right coronary artery have been previously reported in the literature however pseudo-lesion affecting the left anterior descending artery has not been described. The possible mechanisms of this phenomenon and its management are discussed.

Aged↗
PubMed1999

Coronary artery stenting in unstable angina pectoris: a comparison with stable angina pectoris.

OBJECTIVE: To compare early complication rates in unselected cases of coronary artery stenting in patients with stable v unstable angina. SETTING: Tertiary referral centre. PATIENTS: 390 patients with stable angina pectoris (SAP) and 306 with unstable angina (UAP). Patients treated for acute myocardial infarction (primary angioplasty) or cardiogenic shock were excluded. INTERVENTIONS: 268 coronary stents were attempted in 211 patients (30.3%). Stents used included AVE (63%), Freedom (14%), NIR (7%), Palmaz-Schatz (5%), JO (5%), and Multilink (4%). Intravascular ultrasound was not used in any of the cases. All stented patients were treated with ticlopidine and aspirin together with periprocedural unfractionated heparin. RESULTS: 123 stents were successfully deployed in 99 SAP patients v 132 stents in 103 UAP patients. Failed deployment occurred with nine stents in SAP patients, v four in UAP patients (NS). Stent thrombosis occurred in four SAP patients and 11 UAP patients. Multivariate analysis showed no relation between stent thrombosis and clinical presentation (SAP v UAP), age, sex, target vessel, stent length, or make of stent. Stent thrombosis was associated with small vessel size (p < 0.001) and bailout stenting (p = 0.01) compared with elective stenting and stenting for suboptimal PTCA, with strong trends toward smaller stent diameter (p = 0.052) and number of stents deployed (p = 0.06). Most stent thromboses occurred in vessels < 3 mm diameter. CONCLUSIONS: Coronary artery stenting in unstable angina is safe in vessels >/= 3 mm diameter, with comparable initial success and stent thrombosis rates to stenting in stable angina.

Angina Pectoris↗
PubMed1997

Whole-blood test for total cholesterol by a self-metering, self-timing disposable device with built-in quality control.

A whole-blood test for total cholesterol has been developed that is performed in a low-cost disposable flow device without user intervention (after sample addition). The device meters the sample, separates plasma from erythrocytes, and precisely times plasma flow into various reagent compartments, including a quality-assurance chamber. Test results are displayed as a well-defined and easily readable color bar. A quality-control window attests to the integrity of the test components. Here, we describe the assembly and individual functions of the device and report its performance characteristics. Precision and accuracy studies in four clinical studies at independent locations yielded total imprecision of <5% and an average bias of 1.35% vs the Abell-Kendall method.

Cholesterol↗
PubMed1995

Adaptation to spatial offsets.

After prolonged viewing of a three-element target in which the middle element is spatially offset, subsequent viewing of the same three elements in alignment results in the middle element appearing to be offset in the opposite direction. This adaptational aftereffect to a spatial offset was investigated with elements which were spatial-frequency narrowband and equidetectable to ascertain (a) the properties of the mechanisms involved and (b) the nature of the underlying computation. Evidence is presented in favour of an orientational-grouping, rather than a purely positional computation, underlying this aftereffect. A dual site of adaptation is proposed: one which receives input from the orientation extracted from the output of linear filters, and another which receives input from the orientation derived from grouping processes working on the contrast-energy representation. These may correspond to the mechanisms which are thought to underlie the processing of real and subjective contours.

Adaptation, Ocular↗
PubMed1992

Single-stage management of cholesteatoma.

Surgical management of chronic otitis media with cholesteatoma can be performed in a single-stage procedure, with revision surgery necessary because of recurrent disease or electively with unsatisfactory hearing results. We retrospectively reviewed 164 cases with cholesteatoma surgically managed from 1980 through 1986. In total there were 11 tympanoplasties, 36 canal wall-up mastoidectomies, 81 canal wall down modified radical mastoidectomies, and 36 radical mastoidectomies. The recidivistic rate for cholesteatoma in patients available for 5-year followup was 11% for tympanoplasties, 19% for canal wall-up mastoidectomies, 5% for canal wall-down modified radical mastoidectomies, and 0% for radical mastoidectomies. Hearing results were best in patients who required tympanoplasty alone, followed by those who underwent canal wall-down procedures. Single-stage management of cholesteatoma with modified radical mastoidectomy (canal wall-down) required fewer revisions for recidivistic cholesteatoma and achieved better hearing results than canal wall-up procedures. We conclude, therefore, that staging is not necessary. Improved hearing may likely be achieved with a second procedure, but this is at the patient's discretion.

Adolescent↗
PubMed1991

Pneumocystis carinii infection presenting as necrotizing thyroiditis and hypothyroidism.

Extrapulmonary Pneumocystis infection has been increasingly reported in patients with acquired immune deficiency syndrome (AIDS), in particular, recently in association with the increasing use of aerosolized pentamidine. This report describes the unusual presentation of extrapulmonary Pneumocystis infection as a thyroid neck mass and clinical hypothyroidism in a 37-year-old man with hemophilia and AIDS. This case differs from the previously reported single case of isolated thyroid pneumocystosis in the presence of a rapidly enlarging neck mass, lack of previous Pneumocystis, and prior prophylaxis with aerosolized pentamidine. The pathologic and electron microscopic description of the peculiar flocculent necrotic thyroid material is contrasted with typical pulmonary alveolar findings in Pneumocystis pneumonia (PCP), the differential diagnoses of a rapidly expanding neck mass, and diagnostic difficulties of hypothyroidism in patients with AIDS are discussed. Finally, it is emphasized that use of aerosolized pentamidine, although successful for prevention of pulmonary PCP, may be insufficient to prevent extrapulmonary infection.

Acquired Immunodeficiency Syndrome↗