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S P Shah

Publications and source records attributed to S P Shah.

At least 19 recordsLinked to original sources
PubMed2007

Causes of blindness and visual impairment in Pakistan. The Pakistan national blindness and visual impairment survey.

OBJECTIVE: To determine the causes of blindness and visual impairment in adults (> or =30 years old) in Pakistan, and to explore socio-demographic variations in cause. METHODS: A multi-stage, stratified, cluster random sampling survey was used to select a nationally representative sample of adults. Each subject was interviewed, had their visual acuity measured and underwent autorefraction and fundus/optic disc examination. Those with a visual acuity of <6/12 in either eye underwent a more detailed ophthalmic examination. Causes of visual impairment were classified according to the accepted World Health Organization (WHO) methodology. An exploration of demographic variables was conducted using regression modeling. RESULTS: A sample of 16 507 adults (95.5% of those enumerated) was examined. Cataract was the most common cause of blindness (51.5%; defined as <3/60 in the better eye on presentation) followed by corneal opacity (11.8%), uncorrected aphakia (8.6%) and glaucoma (7.1%). Posterior capsular opacification accounted for 3.6% of blindness. Among the moderately visually impaired (<6/18 to > or =6/60), refractive error was the most common cause (43%), followed by cataract (42%). Refractive error as a cause of severe visual impairment/blindness was significantly higher in rural dwellers than in urban dwellers (odds ratio (OR) 3.5, 95% CI 1.1 to 11.7). Significant provincial differences were also identified. Overall we estimate that 85.5% of causes were avoidable and that 904 000 adults in Pakistan have cataract (<6/60) requiring surgical intervention. CONCLUSIONS: This comprehensive survey provides reliable estimates of the causes of blindness and visual impairment in Pakistan. Despite expanded surgical services, cataract still accounts for over half of the cases of blindness in Pakistan. One in eight blind adults has visual loss from sequelae of cataract surgery. Services for refractive errors need to be further expanded and integrated into eye care services, particularly those serving rural populations.

Adult↗
PubMed2006

Pulsatile ocular blood flow in asymmetric age-related macular degeneration.

PURPOSE: Ocular perfusion abnormalities have been proposed in the pathogenesis of age-related macular degeneration (AMD) with differences in pulsatile ocular blood flow (POBF) in eyes with asymmetric AMD in Japanese and Taiwanese patients. The purpose of our study was to observe POBF difference in the fellow eyes of Caucasians with asymmetric AMD. METHODS: This was a cross-sectional study comparing POBF in three groups of patients with asymmetric AMD in the fellow eyes: Group 1 (n=21) with drusen and active choroidal neovascularisation (CNV); Group 2 (n=18) with drusen and disciform scar; Group 3 (n=8) with CNV and disciform scar. The POBF was adjusted for intraocular pressure (IOP), pulse rate (PR), and axial length using multiple regression analysis. Generalised estimation equation model was used to include both eyes in each group. RESULTS: The geometric mean (95% confidence interval) POBF values were as follows: Group 1 with drusen 1097.9 microl/min (957.0, 1259.7) in one eye and the fellow eye with CNV 1090.1 microl/min (932.3, 1274.7); Group 2 with drusen 946.0 microl/min (794.2, 1126.7) and disciform scar 966.2 microll/min (780.3, 1196.4); Group 3 with CNV 877.1 microl/min (628.3, 1224.6) and disciform scar 767.2 microl/min (530.5, 1109.7). Adjusting for differences in axial length, pulse rate and intraocular pressure, no statistically significant difference in POBF was found between fellow eyes in the same subject. CONCLUSIONS: POBF is not different between fellow eyes of Caucasian patients with asymmetric AMD.

Aged, 80 and over↗
PubMed2006

Factors predicting outcome of vitrectomy for diabetic macular oedema: results of a prospective study.

AIM: To determine preoperative demographic, clinical, and optical coherence tomography (OCT) factors which might predict the visual and anatomical outcome at 1 year in patients undergoing vitrectomy and inner limiting membrane peel for diabetic macular oedema (DMO). METHODS: A prospective, interventional case series of 33 patients who completed 1 year follow up. Measurements were taken preoperatively and at 1 year. Outcome measures were logMAR visual acuity (VA) and OCT macular thickness. A priori explanatory variables included baseline presence of clinical and/or OCT signs suggesting macular traction, grade of diabetic maculopathy, posterior vitreous detachment, fluorescein leakage and ischaemia on angiography, presence of subretinal fluid, and peroperative indocyanine green (ICG) use. RESULTS: 33 patients completed 1 year follow up. On average VA deteriorated by 0.035 logMAR (p = 0.40). Macular thickness significantly improved by a mean of 139 microm (95% CI; 211 to 67, p<0.001). Patients with evidence of clinical and/or OCT macular traction significantly improved logMAR acuity (logMAR improvement = 0.08) compared with patients without traction (logMAR deterioration 0.11, p = 0.01). Presence of subretinal fluid significantly predicted worse postoperative result (p = 0.01) CONCLUSION: On average, patients showed a statistically significant improvement in central macular thickness following treatment but a marginal acuity worsening. Presence of subretinal fluid on OCT is hypothesised to be exudative rather than tractional in nature. The visual benefit of vitrectomy for DMO in this study was limited to patients who exhibit signs of macular traction either clinically and/or on OCT.

Aged↗
PubMed2004

Liposomal amphotericin B dry powder inhaler: effect of fines on in vitro performance.

The aim of the present investigation was to improve in vitro pulmonary deposition of amphotericin B (AMB) liposomal dry powder inhaler (LDPI) formulations. Liposomes with negative (AMB1) and positive (AMB2) charge were prepared by the reverse phase evaporation (REV) technique, extruded to reduce size, separated from unentrapped drug and lyophilized using an optimized cryoprotectant to achieve maximum drug retention. Lactose carrier (Sorbolac 400) in varying mass ratio with or without addition of fines (500# sieved Pharmatose 325M) in different mixing sequence were used to formulate AMB LDPI formulations. In vitro evaluation was done with twin stage impinger (TSI) for fine particle fraction. The lactose carrier containing 10% fines was found to be optimum blend at 1:6 mass ratio of liposome: lactose. The addition of fines and order of mixing fines were found to influence the fine particle fraction (FPF) significantly. FPF of LDPI formulations using a Rotahaler (Cipla, India) as delivery device at 30, 60 and 90 L/min were found to be 23.1 +/- 1.5 percent and 17.3 +/- 2.2 percent; 25.3 +/- 1.8 percent and 19.6 +/- 1.5 percent and 28.4 +/- 2.1 percent and 22.9 +/- 1.9 percent for AMB1 and AMB2 respectively.

Administration, Inhalation↗
PubMed1998

DoEpi. Computer-assisted instruction in epidemiology and computing and a framework for creating new exercises.

DoEpi is a series of computer exercises and a framework for making new exercises based on the Epi Info programs for epidemiologic computing. The system contains three outbreak investigations, a research survey, four exercises in advanced Epi Info programming, and four exercises in public health surveillance. The exercises are available via the Internet (www.cdc.gov, under "Publications, Products, and Software") with provision for CME and CEU credit from the Centers for Disease Control and Prevention. They can serve as a useful adjunct to lectures and textbooks in teaching epidemiology or epidemiologic computing. A new DoEpi exercise with hypertext, low-resolution photographs, questions, answers, and an examination can be constructed in hours rather than weeks or months using an Exercise Development "wizard" provided as part of the instructor's module. Epi Info exercises with data files and customized programs require more work to construct but can be added by those with the necessary skills. DoEpi exercises can be used in a variety of ways for different curricula and students of different background levels, including those with English as a second language. Translation of DoEpi exercises into other languages is facilitated by the instructor's module, and construction of new exercises with locally suitable materials is encouraged. DoEpi is based on DOS programs to allow the widest use. The format lends itself to conversion to hypertext programs in the Microsoft Windows and Internet formats at a future date.

Centers for Disease Control and Prevention, U.S.↗
PubMed1998

Nodular amyloidosis of the lung from intravenous drug abuse: an uncommon cause of multiple pulmonary nodules.

Bilateral pulmonary nodules in an immunocompromised host may offer a diagnostic dilemma. We present a case of a human immunodeficiency virus positive patient with history of intravenous drug abuse (IVDA) who was incidentally found to have bilateral multiple pulmonary nodules. She was diagnosed as having nodular pulmonary amyloidosis, presumably serum amyloid A derived (AA) in origin but confirmed not to be of amyloid light chain derived origin (AL), histologically associated with focal birefringent material and foreign body giant cell reaction, probably due to IVDA. Asymptomatic multiple pulmonary nodules in amyloidosis are usually of AL origin; however, recently similar changes have been found in the AA form in patients with Sjogren's syndrome or Crohn's disease. It has not been previously described in association with IVDA. Thus, this case documents a unique cause of bilateral pulmonary nodules due to amyloidosis consequent to IVDA.

Adult↗
PubMed1995

Study of ipratropium bromide inhalation in stable asthma.

An open two weeks short term trial of Ipratropium Bromide (IB) inhalation (0.02 mg per dose) was carried out in 20 stable asthamatics to study its efficacy and safety. Early significant rise in PEFR (P < 0.001) and FEV1 (P < 0.05) was observed after 15 min of IB inhalation and reached significant peak (P < 0.01) after 1 hour which was persistent beyond three hours after IB inhalation. No side effects were observed. It was concluded that Ipratropium Bromide Imhalation is safe and has efficient bronchodilatory effect on short term basis in stable asthmatics.

Administration, Inhalation↗
PubMed1990

Solubilization of salicylamide and acetaminophen by antihistamines in aqueous solution.

The effect of self-association of the antihistaminic drugs pheniramine, chlorpheniramine, and brompheniramine as their maleate salts on the solubilization of salicylamide and acetaminophen in aqueous solution has been investigated. The total solubility of salicylamide increased nonlinearly at lower antihistamine concentrations (less than 0.4 M), but reached limiting linearity (slope = 0.34 mol/mol of antihistamine) at higher concentrations (up to 0.8 M). Salicylamide solubility increases are approximately 10-fold at high concentrations (0.6-0.8 M) of antihistamine, while acetaminophen solubility increases are about fivefold at similar antihistamine concentrations. The solubilization data were analyzed with a stepwise self-association model. Based on a dimer model, the experimental and theoretical log excess salicylamide solubility profiles were in good agreement (r2 = 0.982) except at the lowest chlorpheniramine maleate concentrations. Such deviation at the lowest concentrations increased when trimer and 11-mer models were utilized. To account for this deviation, a monomer-dimer model based on interaction with both the chlorpheniramine maleate monomer and dimer was proposed. This model was in excellent agreement (r2 = 0.996) with the solubility data.

Acetaminophen↗