Temporal bone fractures: otic capsule sparing versus otic capsule violating clinical and radiographic considerations.

OBJECTIVE: To assess the practicality and utility of the traditional classification system for temporal bone fracture (transverse vs. longitudinal) in the modern Level I trauma setting and to determine whether a newer system of designation (otic capsule sparing vs. otic capsule violating fracture) is practical from a clinical and radiographic standpoint. METHODS: The University of Massachusetts Medical Center Trauma Registry was reviewed for the years 1995 to 1997. Patients identified as sustaining closed head injury were reviewed for basilar skull fracture and temporal bone fracture. Clinical and radiographic records were evaluated by using the two classification schemes. RESULTS: A total of 2,977 patients were treated at the trauma center during this time. Ninety (3%) patients sustained a temporal bone fracture. The classic characterization of transverse versus longitudinal fracture (20% vs. 80%, respectively) was unable to be determined in this group; therefore, clinical correlation to complications using that paradigm was not possible. By using the otic capsule violating versus sparing designation, an important difference in clinical sequelae and intracranial complications became apparent. Compared with otic capsule sparing fractures, patients with otic capsule violating fractures were approximately two times more likely to develop facial paralysis, four times more likely to develop CSF leak, and seven times more likely to experience profound hearing loss, as well as more likely to sustain intracranial complications including epidural hematoma and subarachnoid hemorrhage. CONCLUSION: The use of a classification system for temporal bone fractures that emphasizes violation or lack of violation of the otic capsule seems to offer the advantage of radiographic utility and stratification of clinical severity, including severity of Glasgow Coma Scale scores and intracranial complications such as subarachnoid hemorrhage and epidural hematoma.

Cluster analysis applied to building-related illness.

Identifying remediable causes of occupant symptoms in building-related illness is frequently difficult. This is particularly true when the building-wide prevalence of symptoms is comparable to that reported in non-problem buildings. This analysis applied an epidemiological approach to an assessment of a problem building, allowing investigators to visually identify an area of apparent increased symptom density. A cluster analysis approach permitted biostatistical confirmation of the visual cluster. Building-related symptom reporting was statistically significantly associated with a prior physician diagnosis of dust and/or mold allergy. The likely etiology of building occupant symptoms was identified within the region implicated by the cluster analysis. This approach may be useful to focus building evaluations on both the likely physical source and general characteristics of suspect etiologic agents.

Shoulder dystocia and birth trauma in gestational diabetes: a five-year experience.

Over a 5-year period, 210 patients with gestational diabetes mellitus were delivered of offspring weighing greater than or equal to 3500 gm. Only three primary cesarean sections were performed electively because of suspected macrosomia. One hundred twenty patients were delivered vaginally. There were 15 shoulder dystocias but only one permanent brachial plexus injury. Seven of the 15 shoulder dystocias occurred in offspring weighing less than 4000 gm. Of variables examined, only the use of forceps was clearly associated with an increased risk of shoulder dystocia (odds ratio, 5.1). A policy to deliver by cesarean section all fetuses estimated to weigh greater than 4000 gm would considerably increase the number of cesarean sections with minimal fetal benefit.

Northwestern University Twin Study X: Outcome of twin gestations complicated by gestational diabetes mellitus.

Existing data concerning the effect of gestational diabetes on perinatal outcome in twin pregnancies is scant. We hypothesized that altered carbohydrate metabolism would worsen perinatal outcome in twin gestation in a manner similar to singleton gestation. Thirteen twin pregnancies complicated by gestational diabetes mellitus were matched by gestational age at delivery to 13 twin pregnancies unaffected by gestational diabetes. Comparing infants of diabetic mothers to infants of control mothers, there was a trend of greater likelihood of respiratory distress syndrome, hyperbilirubinemia, and prolonged neonatal intensive care nursery admissions. Our experience suggests that altered carbohydrate metabolism in multiple gestations increases the potential for neonatal morbidity.

Infants of diabetic mothers with accelerated fetal growth by ultrasonography: are they all alike?

We studied longitudinal ultrasonographic growth patterns (abdominal circumference, biparietal diameter) initiated early in gestation in 52 pregnancies complicated by pregestational diabetes mellitus and 19 controls. Three predominant patterns of growth were ascertained including a heretofore unrecognized pattern characterized by accelerated abdominal circumference growth (greater than 90th percentile) before 24 weeks' gestational age. Maternal and neonatal anthropometric and metabolic parameters were contrasted for the three patterns. The findings suggest that in some cases of diabetic macrosomia that can be recognized before 24 weeks' gestation, augmented growth may be influenced by factors other than fetal hyperinsulinism.

The limitations of impedance plethysmography in the diagnosis of acute deep venous thrombosis.

We reviewed our experience with impedance plethysmography (IPG) and duplex scanning in the diagnosis of acute deep venous thrombosis (DVT) to determine their respective accuracy and current role in our noninvasive vascular laboratory. During a recent 22-month period 1776 patients were evaluated in our laboratory for DVT. Sixty patients (64 limbs) underwent ascending venography within 48 hours of testing (49 limbs were evaluated by all three modalities). With the venograms used as the reference standard, B-mode scanning correctly identified the presence of acute thrombus in 24 of 27 limbs (88.8%) and the absence of thrombus in 31 of 34 limbs (91.2%), for an overall accuracy of 90.6%. IPG alone was less sensitive (75%) and less specific (44.8%), with an overall accuracy of only 57.1%. Twenty-eight IPGs were performed on patients with negative venous scans. Two positive IPGs were the result of chronic venous occlusion and two others detected clinically significant isolated iliac vein thrombi, but 13 patients had false positive IPGs. One false negative IPG occurred. The difference in the sensitivity of scan alone vs scan plus IPG was not significant (chi 2 = 0.045; difference not significant), but the decrease in specificity was chi 2 = 17.3; p less than 0.001). The rarity of isolated iliac vein thrombosis and the high false positive rate for IPG do not justify its continued use if B-mode venous scanning is available. Although positive scan results may be used confidently to institute therapy without the need for venography, in high-risk patients with a strong clinical suspicion of proximal DVT despite a negative scan venography should be obtained before withholding anticoagulation.

A comparison between fibronectin and Matrigel pretreated ePTFE vascular grafts.

Two distinct series of experiments were performed to compare the behavior of ePTFE vascular grafts coated with basement membrane gel to that of identical grafts coated with fibronectin. Bilateral carotid interposition grafts (10 cm long) were interposed in 16 conditioned mongrel dogs. In the first series of experiments (n = 10), each graft was seeded with radiolabeled endothelial cells and initial endothelial cell adherence was determined. Following restoration of blood flow in the grafts, endothelial cell retention was measured for 24 hours. Seeding efficiency was 66.48% (+/- 13.2) for fibronectin-coated grafts and 56.58% (+/- 13.51) for gel-coated grafts. There was a slow, constant loss of activity during the first 90 minutes of imaging, and at 24 hours of observation the activity remaining on the fibronectin-coated graft was 13.2 +/- 3.98% of the initial graft activity. Although the basement membrane gel had a higher mean activity at 24 hours (18.9 +/- 7.22%), the difference was not statistically significant at any interval. In the second series of animals (n = 6), radiolabeled platelets were injected within 60 minutes following restoration of flow. Total platelet activity on the explanted grafts was 3.36 (+/- 1.35) x 10(5) counts per gram/0.2 minute for the fibronectin-coated grafts. The gel-coated grafts had 2.74 (+/- 1.33) x 10(5) counts per gram/0.2 minute, a difference that was not statistically significant. Thus, despite its theoretical appeal, basement membrane gel was no better than fibronectin in increasing endothelial cell adherence and retention, and the resulting flow surface of grafts treated with either compound appeared to attract platelets to an equal degree.

Bacterial infectibility of chronically implanted endothelial cell-seeded expanded polytetrafluoroethylene vascular grafts.

Vascular prosthetic grafts become more resistant to infection as the interval between implantation and bacteremic challenge increases. Endothelial cell (EC) seeding of such grafts has been shown to improve measurably their ability to resist a bacteremic challenge several weeks after implantation, presumably by reducing the amount of thrombus-free area (TFA) on their luminal surface. However, no investigators have reported the impact of EC seeding on the ability of chronically implanted vascular prostheses to resist a late bacteremic challenge. Bilateral common carotid interposition grafts were placed in 15 adult mongrel dogs with a 4 mm internal diameter, experimental, expanded polytetrafluoroethylene (ePTFE) prosthesis. One animal died shortly after operation and the grafts in two dogs thrombosed, thereby leaving 12 animals with at least one patent graft for subsequent study. At a mean interval of 45 weeks after implantation, five dogs (seven patent grafts) were challenged with an intravenous infusion of 3 X 10(8) radiolabeled Staphylococcus aureus; bacterial adherence and the TFA of the graft's luminal surface were determined for each of the patent grafts. There was no statistically significant difference in bacterial adherence or TFA between EC-seeded and control grafts. At a mean interval of 53 weeks after implantation, the remaining seven dogs (14 patent grafts) received a similar bacterial infusion and the animals were allowed to recover. Five days later, the grafts were harvested and cultured. Once again, there was no significant difference in the infectibility of EC-seeded vs. control grafts.(ABSTRACT TRUNCATED AT 250 WORDS)

Nasopharyngeal masses in adults.

Nasopharyngeal masses in adults present a perplexing problem because of the concern for malignancy. A retrospective review of the records, radiographs and biopsy histology of 57 patients presenting in one year with nasopharyngeal masses at the Massachusetts Eye and Ear Infirmary suggests that persistent pain, epistaxis, trismus, or cervical mass are uncommon in patients with benign histology and should alert the clinician to the probability of malignancy. A high index of suspicion on the part of the clinician is essential for the successful recognition of early lesions. The roles of conventional radiography, polytomography, and computed tomography scans are discussed. Patients with malignant lesions are contrasted with those having benign lesions.

Radiologic evaluation of the normal adult nasopharynx.

Adenoid hypertrophy complicates the radiographic evaluation of the adult nasopharynx. To define the limits of normal soft-tissue thickness of the nasopharynx on the lateral film, I measured the profiles of 2 different groups of adult patients: 60 patients examined by x-ray for trauma who had no sinus disease or nasopharyngeal complaints and 30 patients examined by x-ray who had nasopharyngeal complaints necessitating biopsies. Histologic examinations of the biopsy specimens indicated benign disease, usually caused by an inflammatory process. The asymptomatic group showed a more uniform appearance of the nasopharynx than the symptomatic patients, who had a wide variation in the thickness of the nasopharynx. The symptomatic group manifested nasal and eustachian tube obstruction, frequently associated with serous otitis media. When the soft-tissue thickness of the nasopharynx was correlated with age, nasopharyngeal thickening was unusual in asymptomatic persons older than 30 years. Conversely, persons over 30 with nasopharyngeal thickening were often symptomatic and had biopsies indicating some inflammatory change in the nasopharynx.