Canal geometry changes associated with axial compressive cervical spine fracture

STUDY DESIGN: A laboratory study using isolated ligamentous human cadaveric cervical spines to investigate canal occlusion during (transient) and after (steady-state) axial compressive fracture. OBJECTIVES: To determine whether differences exist between transient and postinjury canal occlusion under axial compressive loading, and to examine the effect of loading rate on canal occlusion. SUMMARY OF BACKGROUND DATA: Prior studies have shown no correlation between neurologic deficit and canal occlusion measurements made on radiographs and computed tomography scans. The authors hypothesized that postinjury radiographic assessment does not provide an appreciation for the transient occlusion that occurs during the traumatic fracture event, which may significantly affect the neurologic outcome. METHODS: Twelve human cervical spines were instrumented with a specially designed canal occlusion transducer, which dynamically monitored canal occlusion during axial compressive impact. Six specimens were subjected to a fast-loading rate (time to peak load, approximately 20 msec), and the other six were subjected to a slow-loading rate (time to peak load, approximately 250 msec). After impact, two different postinjury canal occlusion measurements were performed. RESULTS: Each of the six specimens subjected to the fast-loading rate incurred burst fractures, whereas the slow-loading rate produced six wedge-compression fractures. For the fast-rate group, the postinjury occlusion-measurements were significantly smaller than the transient occlusion. In contrast, transient occlusion was not found to be significantly different from postinjury occlusion in the slow-rate group. All of the comparisons between loading rate groups showed significant differences, with the fast-rate fractures producing larger amounts of canal occlusion in every category. CONCLUSIONS: The findings indicate that even if canal occlusion could be measured immediately after axial compressive trauma, the measurement would underestimate the maximal amount of transient canal occlusion. Therefore, postinjury measurement of canal occlusion may indicate a smaller degree of neurologic deficit than what might be expected if the transient occlusion could be measured.     

Treatment of Cervical Incompetence by Transabdominal Cervicoisthmic Cerclage

Summary: Cervical incompetence is a condition traditionally treated by cervical cerclage which in most cases is inserted via the transvaginal route. However the insertion of a transabdominal cervicoisthmic suture is indicated in those patients with recurrent mid-trimester losses due to an incompetent cervix where it is not technically possible to insert a transvaginal suture. Between 1987 and 1996, 12 women at the Royal Women's Hospital, Melbourne were treated with transabdominal cervicoisthmic cerclage (TCC). Eight patients had cerclage in the nonpregnant state, and 4 were pregnant at the time. The completed pregnancies thus far have resulted in 10 surviving infants, a successful pregnancy rate of 69.2%. This compares favourably with a corrected preTCC successful pregnancy rate of only 13%. There were minimal intraoperative complications in our series. Bleeding, chorioamnionitis and premature rupture of the membranes have been reported elsewhere and occurred in 2 of our patients. Our results and a review of the literature confirms that TCC has an important role in carefully-selected patients.     

Frontal sinus surgery 2004: update of clinical anatomy and surgical techniques

Endoscopic frontal sinus surgery is still considered difficult, risky to perform, and likely to result in a high failure rate. We have previously reported on our technique of endoscopic frontal sinus surgery, stressing the importance of identification and preservation of natural outflow tract. Our study of frontal sinus anatomy shows that the mean frontal ostium anterior—posterior and transverse dimensions are 7.22 ± 2.78 mm and 8.92 ± 2.95 mm, respectively; therefore, dissection of obstructive structures in frontal recess leads to a wide opening of frontal sinus outflow. A key surgical landmark in our technique is the superior attachment of the uncinate process. This article provides an update of the surgical anatomy of the frontal recess region and our surgical technique, as well as a discussion of our approach to frontal sinus revision surgery.     

Linear Nevus Sebaceus Syndrome with bilateral complex limbal choristomas and extraocular muscle involvement

A case of a child with bilateral fleshy limbal masses with a coloboma of the right upper lid is discussed. Systemic examination revealed two patches of alopecia on the right frontoparietal and right occipital areas of the scalp. Punch biopsy and histopathological examination led to the diagnosis of Linear Nevus Sebaceus Syndrome (LNSS) with bilateral complex limbal choristomas. The authors have stated that they do not have a significant financial interest or other relatioship with any product manufacturer or provider of services discussed in this article. The authors also do not discuss the use of off-label products, which includes unlabeled, unapproved, or investigative products or devices.     

Methodology in meta–analysis: a study from Critical Care meta–analytic practice

Methodological aspects of meta-analytic practice, heterogeneity, publication bias, metaregression and effect metric, were investigated in 14 meta-analyses reflecting major therapeutic concern in Critical Care practice. Compared with the standard Q test, the exact Zelen test was more sensitive in identifying heterogeneity. Assessment of heterogeneity impact by the I ² statistic was consistent with inferences afforded by both the Q and Zelen test. Publication bias was subject to test and metric determination: funnel plots exhibited variable asymmetry across studies and between metrics; the regression asymmetry test appeared more sensitive than the rank correlation test; the “trim and fill” method was the most sensitive, but suggested, on the basis of quantification of the effects of potentially missing studies, that meta-analyses may be resistant to such missingness. Metaregression of treatment effect against control risk using Bayesian hierarchical regression in all metrics (log odds ratio, log risk ratio and RD) suggested that naïve linear regression approaches over-diagnosed significant relationships and exhibited regression dilution. Heterogeneity, publication bias and risk related treatment effects all demonstrate estimator and metric dependence; the RD metric would appear the most capricious in this regard.     

Office Systems and Their Influence on Mammography Use in Rural and Urban Primary Care

CONTEXT: Breast cancer screening rates are lower in rural communities. Although studies have addressed barriers to mammography for rural residents, physician practice barriers have received less attention. PURPOSE: Controlled clinical trials have shown that the use of office reminder systems in primary care practices is related to increased clinical care rates. Therefore, we compared office systems use in primary care practices located in rural and urban communities and assessed the impact of these systems on rural-urban differences in mammography utilization. METHODS: We identified female Kansas Medicare beneficiaries aged 65 to 79 from Medicare claims data (N = 24,030) and determined which beneficiaries received a mammogram between April 1, 1999, and March 31, 2001. We linked beneficiaries to their primary care providers and obtained surveys from 180 primary care practices on their use of office reminder systems. FINDINGS: Mammography rates ranged from 20% to 92% (mean = 65%) among the 180 practices. Flowsheets with a mammography prompt were used by 33% of the practices, 38% utilized nonphysician staff to identify women due for mammograms, and 15% used computerized reminder systems. Urban practices used flowsheets more often than rural practices (44% versus 16%, P < 0.001). A multivariable regression model demonstrated higher mammography rates in urban practices, group practices, and practices using mammography flowsheets. CONCLUSIONS: Despite success in randomized controlled trials, reminder systems are not used often by primary care providers and are used even less often in rural compared to urban practices. Consistent implementation may be a major barrier to the successful adaptation of flowsheets by primary care offices.     

Comparison of refractive outcomes using immersion ultrasound biometry and IOLMaster biometry

Background:  The IOLMaster determines axial length using partial coherence interferometry. This study was designed to compare the refractive outcomes of patients who had been measured preoperatively by both immersion ultrasound and IOLMaster biometry.
Methods:  Patients were recruited from those who had undergone cataract surgery during the preceding 12 months by one surgeon at The Queen Elizabeth Hospital (55 eyes from 55 patients). Each patient underwent measurement of axial length by immersion ultrasound and the IOLMaster. Target refraction was determined using an SRK-T formula and the amount that this differed postoperative refraction was calculated for immersion ultrasound and the IOLMaster. These results were then compared.
Results:  Eyes measured longer by the IOLMaster method compared with immersion ultrasound (23.37 ± 0.87 vs. 23.25 ± 0.90 mm, t  = 4.83; P  < 0.0001). However anterior chamber depth was the similar. Postoperatively, final refractive outcome was 0.01 ± 0.63 dioptres (D) more hypermetropic than the target refraction when using the IOLMaster compared with 0.25 ± 0.73 D more myopic when using immersion ultrasound ( t  = 3.83; P  < 0.0001). Seventy-five per cent of patients were within 0.5 D of target refraction and 93% were within 1.0 D when the IOLMaster was used, compared with 49% and 85% within 0.5 and 1.0 D respectively when using immersion ultrasound (χ² = 8.34; P  = 0.04).
Conclusions:  Biometry performed using the IOLMaster produces a more predictable refractive outcome than immersion ultrasound, with patients' spherical equivalent more likely to be closer to their target refraction.     

Physician‐related facilitators and barriers to patient involvement in treatment decision making in early stage breast cancer: perspectives of physicians and patients

Objective To identify patients’ and physicians’ perceptions of physician‐related verbal and nonverbal facilitators and barriers to patient involvement in treatment decision making (TDM) occurring during clinical encounters for women with early stage breast cancer (ESBC). Methods Eligible women were offered treatment options including surgery and adjuvant therapy. Eligible physicians provided care for women with ESBC in either a teaching hospital or an academic cancer centre. In Phase 1, women were interviewed 1–2 weeks after their initial consultation. In Phase 2, women and their physicians were interviewed separately while watching their own consultation on a digital video disk. All interviews were audiotaped, transcribed and analysed. Results Forty women with ESBC and six physicians participated. Patients and physicians identified thirteen categories of physician facilitators of women’s involvement. Of these, seven categories were frequently identified by women: conveyed a rationale for patient involvement in TDM; explained the risk of cancer recurrence; explained treatment options; enhanced patient understanding of information; gave time for TDM; offered a treatment recommendation; and made women feel comfortable. Physicians described similar information‐giving facilitators but less often mentioned other facilitators. Few physician barriers to women’s involvement in TDM were identified. Conclusions Women with ESBC and cancer physicians shared some views of how physicians involve patients in TDM, although there were important differences. Physicians may underestimate the importance that women’s place on understanding the rationale for their involvement in TDM and on feeling comfortable during the consultation.