Role of CT and MRI prior to redo sternotomy in paediatric patients with congenital heart disease.

AIM: To assess the value of computed tomography (CT) and magnetic resonance imaging (MRI) in the preoperative evaluation of congenital heart disease patients about to undergo redo sternotomy. MATERIALS AND METHODS: Forty-three patients (26 male, 17 female, median age 65 months) underwent contrast-enhanced CT and 24 patients (16 male, eight female, median age 89 months) underwent MRI prior to redo sternotomy for congenital heart disease. The informed consent requirement was waived by the institutional review board for this Health Insurance Portability and Accountability Act (HIPAA) compliant study. A standardized CT protocol utilizing a 64 section multidetector machine and an unenhanced and contrast-enhanced MRI multisequence protocol was used. Images were qualitatively graded and retrosternal distances were measured as part of a risk assessment score. RESULTS: There were no statistically significant differences between the observers' grades regarding most retrosternal structures at both CT and MRI, separately (p > 0.05); furthermore, both readers found CT to be superior to MRI in qualitative grading except one reader's grades for shunts/conduits (p = 0.107). κ-values were good to excellent (κ ≥ 0.61) for most structures in qualitative grading of cases and risk assessment scores. There were no significant differences between grades of important structures using the same technique based on Friedman's test (p > 0.05). Analysis showed no difference between risk scores given to CT and MRI patients (p > 0.05). CONCLUSION: The present findings demonstrate the value of imaging to evaluate retrosternal anatomy. CT could be more valuable than MRI and could play a pivotal role in the surgical planning of CHD patients prior to redo operations.

Evidence of acute myocardial infarction on CT.

Improvements in CT technology, specifically with respect to the development of multi-row detector CT, have increased the ability to detect acute myocardial ischaemia. This case report details the finding of decreased myocardial enhancement on CT in a patient who complained of acute chest symptomalogy and was diagnosed with acute myocardial infarction, which was subsequently confirmed by cardiac catheterization. Given the variability of the clinical presentation of acute myocardial infarction, greater attention should be paid by radiologists to myocardial enhancement in patients with significant coronary risk factors, as evidence of acute myocardial infarct or ischaemia may be detected.

The remodeling of human gingival tissues following gingivectomy.

A total of 30 facial gingivectomies were carried out for reduction of suprabony pockets (mean +/- S.D. preoperative pocket depth 2.8 mm +/- 0.3 mm). Remodeling of the gingival margin was monitored by clinical measurements. The following techniques were utilized: A polyvinyl stent was constructed for each surgical quadrant. This stent covered the occlusal margins of the involved teeth and contained the fixed point of reference. Preoperatively, the following measurements were taken: the distance from the fixed point to (a) the height of the free gingival margin, and (b) the base of the clinical pocket. For control purposes similar measurements were taken at the facial surface of an adjacent tooth. A standard gingivectomy to the base of the clinical pocket was then performed and a periodontal dressing was applied for 1 week. Utilizing the stent (fixed point of reference), measurements were taken of the healing margin and control sites inn the same manner as preoperatively; 1,4,8 and 12 weeks after surgery. Our findings indicate that 12 weeks after gingivectomy, the newly formed free gingival margin was located coronally to the line of incision in all cases. The mean pocket depth at 12 weeks after surgery was 0.7 mm +/- 0.2 mm. However, the mean gain in coronal marginal height was 1.2 mm +/- 0.3 mm. Thus, a clinical coronal pocket closure of about 0.5 mm seemed to have taken place at the soft tissue-tooth interface. Measurements at the nonoperated control site showed no significant variations in crevicular depth during the experimental period. We therefore conclude that the excisional reduction of a crevice to 0 mm depth was altered by gingival remodeling during the healing phase. In our experience, this remodeling took place within 3 months after surgery and clinically appeared as a limited coronal pocket closure and gain of marginal height.