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P Maheshwari

Publications and source records attributed to P Maheshwari.

8 recordsLinked to original sources
PubMed2000

Secondary fractures of Le Fort I osteotomy.

PURPOSE: To report the ophthalmic complications of Le Fort I osteotomy for the correction of dentofacial deformities and to determine the maximal compressive loads applied during pterygomaxillary separation in a cadaver model. METHODS: Two cases of ophthalmic complications arising after Le Fort I osteotomy are reported. Le Fort I osteotomy was performed on five cadavers. The maximal compressive load applied during pterygomaxillary separation was recorded with a 10 kN (3,000 lbf) load cell of a MTS Mini-Bionix servo-hydraulic machine (MTS, Eden Prairie, MN, U.S.A.). A paired t test was used to compare forces applied to the right and left sides. Computed tomography scans of each specimen were obtained after Le Fort I osteotomy to document secondary fractures. The skulls were subsequently stained with 1% fuschin red to highlight secondary fractures. RESULTS: Maximum compressive loads during pterygomaxillary separation ranged from 22 N (5.0 lbf) to 162 N (36.5 lbf), with an average of 106 N (23.8 lbf) (SD 47.6 N [10.7 lbf]). Forces applied on the first operative side were significantly greater than forces applied on the second operative side (p = 0.0034). Secondary fractures were found in three specimens by computed tomography and in two specimens by 1% fuschin red. All secondary fractures occurred on the second operative side. CONCLUSION: Secondary fractures in the Le Fort I osteotomy procedures occurred on the side opposite the greater maximal compressive load and on the second operative side.

Adult↗
PubMed2000

Mechanical strength of fracture callus in osteopenic bone at different phases of healing.

OBJECTIVES: To quantify and compare peak bending force and stiffness of fractured femurs during healing of ovariectomized (OVX) and sham-operated (SHAM) rats. DESIGN: Temporal biomechanical animal study. SETTING: Rat femurs were fractured and surgically fixed by a qualified surgeon. The inherent instability of the fixation system employed produced delayed union of the fracture. All biomechanical assessments were performed with servohydraulic test machines (Instron Inc., Canton, MA, U.S.A.; and MTS Corp., Eden Prairie, MN, U.S.A.). INTERVENTION: OVX was performed sixteen weeks before femur fracture, and the effect of OVX on healing fractures was determined. MAIN OUTCOMES: Peak bending force and stiffness of the healing femurs at four, six, and eight weeks after fracture. RESULTS: Peak bending loads of the healing fractured femurs in the OVX and SHAM animals were not significantly different. Peak bending loads for the OVX animals at four and six weeks were significantly lower than the peak load at eight weeks (p < 0.05), whereas no difference was found in the peak load with respect to time for the SHAM animals. Both SHAM and OVX animals had greater bending stiffness of the healing fractured femur after eight weeks of healing than at four weeks (p < 0.05). CONCLUSIONS: OVX is known to reduce cancellous bone mass and strength, but the effect of OVX on healing of fractures in cortical bone is controversial. This study, using a delayed-union model, found no significant differences between OVX and SHAM animals in the breaking strength of healing fractures.

Animals↗
PubMed1997

Transmyocardial laser revascularisation combined with coronary artery bypass grafting without cardiopulmonary bypass.

OBJECTIVE: To achieve complete myocardial revascularisation in patients with diffuse coronary artery disease, patients with inordinately high risk of cardiopulmonary bypass (CPB) like severe systemic disease or diffuse atherosclerosis of the aorta. METHODS: We have adopted the technique of combining coronary artery bypass grafting (CABG) with transmyocardial laser revascularisation (TMLR) using 1000 W CO2 laser machine. TMLR is done to areas supplied by ungraftable arteries, while CABG without cardiopulmonary bypass is done to the left anterior descending artery (LAD) and/or right coronary artery (RCA). TMLR + CABG on beating heart without CPB has been performed on 56 patients. Age ranged from 37 to 81 years with a mean of 56.17. Four patients were in renal failure, two were redo CABG. Preoperatively 39.28% patients had angina class III and 10.71% had angina class IV. Four patients were on preoperative IABP support. RESULTS: The mean number of grafts was 1.09. Internal thoracic artery (ITA) was used in 96.4% of the patients. Five patients showed elevation of CPK-MB, while three patients had an increase in Troponin T. Mortality was 1.8% (one patient died of intractable ventricular arrhythmia). The mean follow-up is 9.2 months. Myocardial perfusion scanning showed a stepwise improvement in reversible ischemia increasing from 52% at baseline to 91% at 12 months; 90.9% of the patients were angina free at 12 months. Metabolic stress test demonstrated an average increase in exercise tolerance from 5.2 min at baseline to 9.4 min at 12 months. Metabolic equivalents (METs) increased from 4.5 at baseline to 9.4 at 12 months. The average 44% Karnofsky score preoperative also increased to 86% at 12 months. CONCLUSIONS: Our results indicate that the technique is surgically feasible and safe, with excellent short term results.

Adult↗
PubMedDate not supplied

Clinical features, site of involvement, bacteriologic findings, and outcome of infective endocarditis in intravenous drug users.

BACKGROUND: Intravenous drug use is an increasingly common condition predisposing to infective endocarditis. Data on infective endocarditis in intravenous drug users are limited. OBJECTIVE: To determine the clinical features, bacteriologic findings, site of involvement, complications, and mortality associated with infective endocarditis in intravenous drug users. METHODS: Cohort study of intravenous drug users with native valve infective endocarditis. RESULTS: A total of 125 cases of infective endocarditis occurred in 114 patients (84 cases [67%] in men and 41 cases [32%] in women) with a mean (+/- SD) age of 37 +/- 7 years. The tricuspid valve was involved in 58 cases (46%), the mitral valve in 40 cases (32%), and the aortic valve in 24 cases (19%). The microorganisms identified included Staphylococcus in 82 cases (65.6%) and Streptococcus in 32 cases (25.6%). Twenty-three patients (18%) underwent surgery, and two (9%) of them died. One hundred two patients (82%) were treated medically, and nine (9%) of them died. Fifteen patients (63%) with aortic valve involvement vs 17 patients (17%) without aortic valve involvement underwent surgery or died without surgery (odds ratio, 8.24; 95% confidence interval, 3.1 to 21.8). Among the survivors, at least one major cardiovascular complication occurred in 79 cases (69.3%). CONCLUSIONS: Infective endocarditis in intravenous drug users affects the right and left sides of the heart with approximately equal frequency. At present, more than 90% of cases of infective endocarditis in intravenous drug users in Chicago are caused by staphylococci or streptococci. Involvement of the aortic valve is predictive of increased morbidity and mortality in intravenous drug users with infective endocarditis. With medical treatment, and surgery when medical treatment fails, intravenous drug users with infective endocarditis have an in-hospital survival rate of 91%.

Adult↗