CT of hemangiomas of the upper airways in children

OBJECTIVE: Hemangiomas of the airways in infants are commonly diagnosed at bronchoscopy performed for the investigation of stridor or other respiratory symptoms. Occasionally on bronchoscopy the appearances are atypical or the entire extent of the suspected hemangioma cannot be appreciated. We report on the clinical usefulness of dynamic contrast-enhanced CT in the evaluation of suspected hemangiomas of the airways in infants. CT findings of 11 infants who underwent investigation for a suspected airway hemangioma were correlated with bronchoscopic findings. CONCLUSION: Dynamic contrast-enhanced CT is a valuable noninvasive method for the evaluation of airway hemangiomas. Although it can be used to confirm the diagnosis in patients with equivocal findings on bronchoscopy, we believe that CT findings are specific enough that CT can be recommended as the primary method of establishing the diagnosis. Multiplanar reconstructions illustrate the location, extent, and degree of luminal narrowing and any involvement of adjacent tissues.     

Proteases, extracellular matrix, and cancer: a workshop of the path B study section

The role of the extracellular matrix (ECM) in the tumor microenvironment is not limited to being a barrier against tumor invasion. The ECM is a reservoir of cell binding proteins and growth factors that affect tumor cell behavior. It is also substantially modified by proteases produced by tumor cells or stroma cells. As a result of the activity of these proteases, cell-cell and cell-ECM interactions are altered, new biologically active ECM molecules are generated, and the bioavailability and activity of many growth factors, growth factor receptors, and cytokines are modified. ECM-degrading proteases also play a critical role in angiogenesis, where they can act as positive as well as negative regulators of endothelial cell proliferation and vascular morphogenesis. This review article summarizes some of the most relevant findings made over the recent years that were discussed at a workshop organized by the Path B Study Section of the National Institutes of Health in October 2002.     

The R245X mutation of PCDH15 in Ashkenazi Jewish children diagnosed with nonsyndromic hearing loss foreshadows retinitis pigmentosa

Usher syndrome is a frequent cause of the combination of deafness and blindness due to retinitis pigmentosa (RP). Five genes are known to underlie different forms of Usher syndrome type I (USH1). In the Ashkenazi Jewish population, the R245X mutation of the PCDH15 gene may be the most common cause of USH1 (Ben-Yosef T, Ness SL, Madeo AC, Bar-Lev A, Wolfman JH, Ahmed ZM, Desnick RK, Willner JP, Avraham KB, Ostrer H, Oddoux C, Griffith AJ, Friedman TB N Engl J Med 348: 1664-1670, 2003). To estimate what percentage of Ashkenazi Jewish children born with profound hearing loss will develop RP due to R245X, we examined the prevalence of the R245X PCDH15 mutation and its carrier rate among Ashkenazi Jews in Israel. Among probands diagnosed with nonsyndromic hearing loss not due to mutations of connexin 26 (GJB2) and/or connexin 30 (GJB6), and below the age of 10, 2 of 20 (10%) were homozygous for the R245X mutation. Among older nonsyndromic deaf individuals, no homozygotes were detected, although one individual was heterozygous for R245X. The carrier rate of the R245X mutation among the normal hearing Ashkenazi population in Israel was estimated at 1%. Ashkenazi Jewish children with profound prelingual hearing loss should be evaluated for the R245X PCDH15 mutation and undergo ophthalmologic evaluation to determine whether they will develop RP. Rehabilitation can then begin before loss of vision. Early use of cochlear implants in such cases may rescue these individuals from a dual neurosensory deficit.     

Peripheral arterial tonometry: a diagnostic method for detection of myocardial ischemia induced during mental stress tests: a pilot study

BACKGROUND: Mental stress testing is considered a reliable method for diagnosing patients with coronary heart disease (CHD) who may be at risk for future events. It has been shown recently that myocardial ischemia induced during mental stress tests is specifically associated with peripheral arterial vasoconstriction. HYPOTHESIS: The study was undertaken to test the diagnostic capability of peripheral arterial tonometry (PAT) to detect peripheral arterial vasomotor changes. METHODS: We monitored pulsatile finger blood volume changes using a specially designed finger plethysmograph, PAT that can detect peripheral arterial vasomotor changes. Equilibrium radionuclide angiography (ERNA) was simultaneously performed in 18 male patients at rest and during a mental arithmetic stress test with harassment. All patients had previously diagnosed coronary disease and positive exercise tests. Myocardial ischemia was diagnosed by ERNA when global ejection fraction fell > or = 8% during mental stress or new (or worsened) focal wall motion abnormalities occurred. Peripheral arterial tonometry tracings were considered abnormal when the pulse wave amplitude decreased by > or = 20% from baseline. RESULTS: In 18 patients there were 16 usable studies. In eight patients, both ERNA and PAT were abnormal, and in six patients the tests were negative by both methods. In two cases, the results were discordant. Therefore, when considering an abnormal PAT tracing as indicative of mental stress-driven myocardial ischemia, concordance of the two methods was 88%. CONCLUSION: The use of PAT may facilitate both clinical testing and research during mental stress.     

Suicide bombing attacks: update and modifications to the protocol

OBJECTIVE: To review the experience of a large-volume trauma center in managing and treating casualties of suicide bombing attacks. SUMMARY BACKGROUND DATA: The threat of suicide bombing attacks has escalated worldwide. The ability of the suicide bomber to deliver a relatively large explosive load accompanied by heavy shrapnel to the proximity of his or her victims has caused devastating effects. METHODS: The authors reviewed and analyzed the experience obtained in treating victims of suicide bombings at the level I trauma center of the Hadassah University Hospital in Jerusalem, Israel from 2000 to 2003. RESULTS: Evacuation is usually rapid due to the urban setting of these attacks. Numerous casualties are brought into the emergency department over a short period. The setting in which the device is detonated has implications on the type of injuries sustained by survivors. The injuries sustained by victims of suicide bombing attacks in semi-confined spaces are characterized by the degree and extent of widespread tissue damage and include multiple penetrating wounds of varying severity and location, blast injury, and burns. CONCLUSIONS: The approach to victims of suicide bombings is based on the guidelines for trauma management. Attention is given to the moderately injured, as these patients may harbor immediate life-threatening injuries. The concept of damage control can be modified to include rapid packing of multiple soft-tissue entry sites. Optimal utilization of manpower and resources is achieved by recruiting all available personnel, adopting a predetermined plan, and a centrally coordinated approach. Suicide bombing attacks seriously challenge the most experienced medical facilities.     

The postoperative blood-sparing efficacy of oral versus intravenous tranexamic acid after total knee replacement

To assess the blood-sparing efficacy of tranexamic acid (TA) administered orally or via a variable IV infusion, 80 healthy patients undergoing elective total knee replacement were studied according to a prospective, controlled, randomized, single-blinded study design. Patients were allocated to one of four treatment groups. In group TA-long, 30 min before deflation of the limb tourniquet, an IV bolus dose of TA 15 mg/kg was administered over 30 min. Thereafter, a constant IV infusion of 10 mg . kg(-1) . h(-1) was administered until 12 h after final deflation of the limb tourniquet. In group TA-short, a similar regimen was followed; however, the constant IV infusion was discontinued 2 h after final deflation of the limb tourniquet (time of discharge from the postanesthesia care unit). Thereafter, oral TA 1 g was administered after 6 and 12 h. In group TA-oral, 60 min before surgery an oral dose of TA 1 g was administered. After surgery, a similar dose of TA was administered every 6 h for the next 18 h. In the control group, TA was not administered. At patient discharge, postoperative allogeneic blood administration was significantly more in group Control when compared with each of the three TA treatment groups. Because oral drug administration is simple and does not require specific infusion equipment, the authors suggest that oral TA is a superior blood-sparing strategy compared with IV drug administration.     

Extracardiac reconstruction of anomalous superior systemic venous return

A heretofore undescribed surgical approach for correcting a rare congenital cardiac malformation consisting of an absent right superior vena cava with persistent left superior vena cava associated with situs solitus draining into the left atrium is presented. The intra-atrial septum was intact. Normal anatomy was achieved and recovery was uneventful.     

Dysphagia and aspiration after chemoradiotherapy for head-and-neck cancer: which anatomic structures are affected and can they be spared by IMRT?

PURPOSE: To identify the anatomic structures whose damage or malfunction cause late dysphagia and aspiration after intensive chemotherapy and radiotherapy (RT) for head-and-neck cancer, and to explore whether they can be spared by intensity-modulated RT (IMRT) without compromising target RT. METHODS AND MATERIALS: A total of 26 patients receiving RT concurrent with gemcitabine, a regimen associated with a high rate of late dysphagia and aspiration, underwent prospective evaluation of swallowing with videofluoroscopy (VF), direct endoscopy, and CT. To assess whether the VF abnormalities were regimen specific, they were compared with the VF findings of 6 patients presenting with dysphagia after RT concurrent with high-dose intra-arterial cisplatin. The anatomic structures whose malfunction was likely to cause each of the VF abnormalities common to both regimens were determined by literature review. Pre- and posttherapy CT scans were reviewed for evidence of posttherapy damage to each of these structures, and those demonstrating posttherapy changes were deemed dysphagia/aspiration-related structures (DARS). Standard three-dimensional (3D) RT, standard IMRT (stIMRT), and dysphagia-optimized IMRT (doIMRT) plans in which sparing of the DARS was included in the optimization cost function, were produced for each of 20 consecutive patients with advanced head-and-neck cancer. RESULTS: The posttherapy VF abnormalities common to both regimens included weakness of the posterior motion of the base of tongue, prolonged pharyngeal transit time, lack of coordination between the swallowing phases, reduced elevation of the larynx, and reduced laryngeal closure and epiglottic inversion, contributing to a high rate of aspiration. The anatomic structures whose malfunction was the likely cause of each of these abnormalities, and that also demonstrated anatomic changes after RT concurrent with gemcitabine doses associated with dysphagia and aspiration, were the pharyngeal constrictor muscles (median thickness near midline 2.5 mm before therapy vs. 7 mm after therapy; p = 0.001), the supraglottic larynx (median thickness, 2 mm before therapy vs. 4 mm after therapy; p < 0.001), and, similarly, the glottic larynx. The constrictors and the glottic and supraglottic larynx were, therefore, deemed the DARS. The lowest maximal dose delivered to a stricture volume was 50 Gy. Reducing the volumes of the DARS receiving > or =50 Gy (V(50)) was, therefore, a planning and evaluation goal. Compared with the 3D plans, stIMRT reduced the V(50) of the pharyngeal constrictors by 10% on average (range, 0-36%, p < 0.001), and doIMRT reduced these volumes further, by an additional 10% on average (range, 0-38%; p <0.001). The V(50) of the larynx (glottic + supraglottic) was reduced marginally by stIMRT compared with 3D (by 7% on average, range, 0-56%; p = 0.054), and doIMRT reduced these volumes by an additional 11%, on average (range, 0-41%; p = 0.002). doIMRT reduced laryngeal V(50) compared with 3D, by 18% on average (range 0-61%; p = 0.001). Certain target delineation rules facilitated sparing of the DARS by IMRT. The maximal DARS doses were not reduced by IMRT because of their partial overlap with the targets. stIMRT and doIMRT did not differ in target doses, parotid gland mean dose, spinal cord, or nonspecified tissue maximal dose. CONCLUSIONS: The structures whose damage may cause dysphagia and aspiration after intensive chemotherapy and RT are the pharyngeal constrictors and the glottic and supraglottic larynx. Compared with 3D-RT, moderate sparing of these structures was achieved by stIMRT, and an additional benefit, whose extent varied among the patients, was gained by doIMRT, without compromising target doses. Clinical validation is required to determine whether the dosimetric gains are translated into clinical ones.     

Working memory performance in poor outcome schizophrenia: relationship to age and executive functioning

Performance on the Letter-Number Sequencing (LNS) and Wisconsin Card Sorting Tests (WCST) have been shown to be significantly correlated in patients with schizophrenia, a relationship postulated to be due to working memory demands of the two tests (Gold, Carpenter, Randolph, Goldberg, & Weinberger, 1997). An alternative explanation for the association between these two tests is their sorting demands, in that both require sorting of information albeit in slightly different ways. If the latter explanation is valid, then working memory tasks that do not require sorting or other conceptualization demands should be less predictive of WCST performance than LNS. These hypotheses were examined in 34 poor outcome patients with schizophrenia, one-half of whom were over the age of 65. Patients were evaluated on Digit Span Forward, spatial working memory, LNS, and the WCST. It was found that WCST performance was significantly associated with performance on the LNS but no other working memory task. Age related performance differences were greatest on the WCST Categories and floor effects were noted on this test in one-half of the subjects. Analyses predicting WCST Categories in subjects whose scores were greater than zero (n = 16) also demonstrated that LNS, but not Digit Span or spatial working memory (any delay) predicted WCST performance. These findings indicate that LNS may be an index of executive functioning, particularly in patients who cannot perform the WCST.