Geometric variability of the scoliotic spine using statistics on articulated shape models.

This paper introduces a method to analyze the variability of the spine shape and of the spine shape deformations using articulated shape models. The spine shape was expressed as a vector of relative poses between local coordinate systems of neighboring vertebrae. Spine shape deformations were then modeled by a vector of rigid transformations that transforms one spine shape into another. Because rigid transformations do not naturally belong to a vector space, conventional mean and covariance could not be applied. The Fréchet mean and a generalized covariance were used instead. The spine shapes of a group of 295 scoliotic patients were quantitatively analyzed as well as the spine shape deformations associated with the Cotrel-Dubousset corrective surgery (33 patients), the Boston brace (39 patients), and the scoliosis progression without treatment (26 patients). The variability of intervertebral poses was found to be inhomogeneous (lumbar vertebrae were more variable than the thoracic ones) and anisotropic (with maximal rotational variability around the coronal axis and maximal translational variability along the axial direction). Finally, brace and surgery were found to have a significant effect on the Fréchet mean and on the generalized covariance in specific spine regions where treatments modified the spine shape.

Current management of infants and children with single ventricle anatomy.

Children with single ventricle anatomy are among the most complicated and challenging patients encountered in pediatric cardiology. Current management involves staged surgical procedures, beginning with neonatal palliation and followed by a bidirectional cavopulmonary anastomosis in infancy and culminating in the Fontan procedure. The Fontan procedure, despite separating the circulation, remains a palliative procedure with many long-term concerns. This report discusses the staged surgical management of patients with single ventricle anatomy and the nursing issues relevant to each stage.

Information provision, patient involvement, and emotional support: prospective areas for improving anesthetic care.

PURPOSE: To explore patients' perceptions of anesthetic care as measured by a patient-centered care survey. Specifically, the survey examined patient views of multiple diverse dimensions of care that are not typically fully addressed among patients receiving anesthesia services, namely opinions on Information Provision, Involvement in Care, Respect Shown, Physical Comfort, and Emotional Support. METHOD: A total of 268 patients responded to a patient-centered care survey, a self-report factor analytically derived instrument designed to measure the aforementioned dimensions of care. RESULTS: Analyses revealed that the highest ratings of care were given to Physical Comfort and Respect. Ratings of Information Provision, Involvement, and Emotional Support were significantly lower. Ratings did not differ as a function of site of service, inpatient vs day surgery, surgical service, type of anesthetic, or anesthesiologist. DISCUSSION: The findings generated from the study are of value in obtaining a broader understanding of anesthesia services from the patient's perspective, and also in directing quality improvement initiatives. Other departments of anesthesiology interested in quality improvement initiatives may similarly benefit from measurement of patient-centered care.

Direct functional analysis of epitope-specific CD8+ T cells in peripheral blood.

The functional status of virus-specific CD8+ T cells is important for the outcome and the immunopathogenesis of viral infections. We have developed an assay for the direct functional analysis of antigen-specific CD8+ T cells, which does not require prolonged in vitro cultivation and amplification of T cells. Whole blood samples were incubated with peptide antigens for <5 h, followed by staining with peptide-MHC tetramers to identify epitope-specific T cells. The cells were also stained for the activation marker CD69 or for the production of cytokines such as interferon-gamma (IFNgamma) or tumor necrosis factor-alpha (TNFalpha). With the combined staining with tetramer and antibodies to CD69 or cytokines the number of antigen-specific CD8+ T cells as well as the functional response of each individual cell to the cognate antigen can be determined in a single experiment. Virus-specific CD8+ T cells that are nonfunctional, as well as those that are functional under the same stimulating conditions can be simultaneously detected with this assay, which is not possible by using other T-cell functional assays including cytotoxicity assay, intracellular cytokine staining, and enzyme-linked immunospot (ELISPOT) assay.

CCR7 expression and memory T cell diversity in humans.

CCR7, along with L-selectin and LFA-1, mediates homing of T cells to secondary lymphoid organs via high endothelial venules (HEV). CCR7 has also been implicated in microenvironmental positioning of lymphocytes within secondary lymphoid organs and in return of lymphocytes and dendritic cells to the lymph after passage through nonlymphoid tissues. We have generated mAbs to human CCR7, whose specificities correlate with functional migration of lymphocyte subsets to known CCR7 ligands. We find that CCR7 is expressed on the vast majority of peripheral blood T cells, including most cells that express adhesion molecules (cutaneous lymphocyte Ag alpha(4)beta(7) integrin) required for homing to nonlymphoid tissues. A subset of CD27(neg) memory CD4 T cells from human peripheral blood is greatly enriched in the CCR7(neg) population, as well as L-selectin(neg) cells, suggesting that these cells are incapable of homing to secondary lymphoid organs. Accordingly, CD27(neg) T cells are rare within tonsil, a representative secondary lymphoid organ. All resting T cells within secondary lymphoid organs express high levels of CCR7, but many activated cells lack CCR7. CCR7 loss in activated CD4 cells accompanies CXC chemokine receptor (CXCR)5 gain, suggesting that the reciprocal expression of these two receptors may contribute to differential positioning of resting vs activated cells within the organ. Lymphocytes isolated from nonlymphoid tissues (such as skin, lung, or intestine) contain many CD27(neg) cells lacking CCR7. The ratio of CD27(neg)/CCR7(neg) cells to CD27(pos)/CCR7(pos) cells varies from tissue to tissue, and may correlate with the number of cells actively engaged in Ag recognition within a given tissue.

Effects of 2,4-dichlorophenol on the net-spinning behavior of hydropsyche slossonae larvae (Trichoptera; Hydropsychidae), an early warning signal of chronic toxicity.

In order to assess the potential of hydropsychid capture net anomalies as a bioindicator of chronic toxicity in streams and rivers, the effects of 2,4-dichlorophenol (2,4-DCP) exposure on the net-spinning behavior of Hydropsyche slossonae were examined for anomalies after 0, 5, 10, 15, and 20 exposure days to gradient concentration of 2,4-dichlorophenol. The net-spinning behavior was significantly affected when larvae were exposed to 1.0, 10, 25, and 50 microg small middle dotL(-1), as expressed by the occurrence of two distinct abnormalities. The first one was a distortion of the midline meshes, where the normal diamond-shape structure is disrupted and the meshes are separated by extra strands (called "midline anomaly). The second aberration observed was called "chaotic net, where the nets are highly irregular without any real structure or well-defined areas. A good correlation was found between the chaotic net frequencies and the reduction of ATP concentrations in the larvae, indicating possible uncoupling effects of 2,4-DCP on the oxidative phosphorylation process. Toxicity curves demonstrate that the sensitivity threshold of chaotic net frequencies ranged from 3.5 to 7 microg small middle dotL(-1), which is highly sensitive compared with other sublethal effects of 2,4-DCP on other aquatic species.

Anomalies on capture nets of Hydropsyche slossonae larvae (Trichoptera; Hydropsychidae) following a sublethal chronic exposure to cadmium.

A laboratory study on the sublethal effects of cadmium (Cd) on the net-spinning process of the larvae of Hydropsyche slossonae was conducted in order to assess the potential of net anomalies as an indicator of chronic exposure to Cd. Two major anomalies with different frequency levels were identified after chronic exposure to 0.37, 1.2, 11.6, 21.4 and 43.3 microg l(-1) of Cd. The first was a distortion of the midline meshes where the diamond-shape structure is disrupted and the meshes are separated by extra strands (called 'midline' anomaly). The second aberration consisted of a distortion of the rectilinear structure of net opening by strands being fused or added over the meshes (called 'crossover' anomaly). The midline distortion may be linked to a physiological stress caused by Cd, which can affect the control of the net-spinning process. It was not possible to relate the crossover aberrations to a specific toxic action of Cd, but data indicated that both anomalies are independent from each other and that two modes of action could be implicated. Protein analyses of capture nets have revealed silk polypeptide modifications at the highest Cd concentration tested, indicating a possible effect of Cd interaction with silk proteins. However, neither a gradient-concentration nor a time-dependent response could be established with both aberration frequencies. Silk protein modifications would rather play a secondary role in the appearance of both net anomalies, and mostly at a high concentration level. Finally, the toxicity curves (EC(50)) show that the sensitivity threshold for both types of aberration ranged from 1 to 5 microg l(-1) which is highly sensitive compared with other sublethal effects of Cd on other macroinvertebrate species. Hence, the use of capture-net anomalies of hydropsychid larvae would represent a valuable indicator of sublethal toxicity induced by Cd and possibly by other metals in running waters.

Liver disease in children with cystic fibrosis: US-biochemical comparison in 195 patients.

PURPOSE: To determine if abnormal liver architecture at ultrasonography (US) is related to abnormal function in children with cystic fibrosis (CF). MATERIALS AND METHODS: For 1 year, all 195 children (112 boys, 83 girls; mean age, 8.5 years) attending a CF clinic underwent abdominal US and a standard set of liver function tests. Aspartate aminotransferase, alanine aminotransferase, and gamma-glutamyltransferase levels were analyzed. US signs were interpreted as follows: hypoechogenicity with prominent portal tracks as edema, hyperechogenicity as steatosis, and increased attenuation and nodules within or at the edge of the liver as cirrhosis. Signs of portal hypertension also were sought. US signs were compared with liver function test results. RESULTS: Liver sonograms were abnormal in 38 children (19%); of these, 24 (63%) had abnormal test results. The 157 children with normal liver architecture had a much lower prevalence of biochemical abnormality (33 patients [21%]; P < or = .001). All eight children with signs of portal hypertension had abnormal test results. Fourteen (82%) of 17 children with signs of cirrhosis had abnormal liver function. Eight (57%) of 14 patients with signs of steatosis had abnormal function. Diffuse hypoechogenicity of the liver with prominent portal tracks in 16 patients was associated with abnormal function in only five patients. CONCLUSION: The relation between abnormal liver architecture at US and results of three liver function tests in children with CF was significant. The most specific US abnormalities related to abnormal function are signs suggestive of portal hypertension and cirrhosis.

In utero sonographic diagnosis of diaphragmatic hernia with hepatic protrusion into the pericardium mimicking an intrapericardial tumour.

A case of right-sided congenital diaphragmatic hernia was detected at 33 weeks of gestation. Fetal echocardiography revealed the presence of an intrapericardial mass (3.5 x 3 cm) localized at the right of the heart and surrounded by a massive pericardial effusion. This mass had the same echogenicity as the liver, with which it shared vascular channels. The diagnosis of right diaphragmatic hernia with protrusion of hepatic tissue into the pericardial sac and secondary pericardial effusion was made and confirmed after birth. In utero diagnosis of this anomaly enabled correct assessment of perinatal risk, and optimal fetal and infant management.

Prenatal diagnosis of fetal anomalies during the second trimester of pregnancy: their characterization and delineation of defects in pregnancies at risk.

During a follow-up study of 19,790 pregnancies at risk for a genetic disease, from 1968 to 1989, 1083 fetuses were found to have an anomaly during the second trimester, leading to 977 terminations of pregnancy. Neural tube defects (31.4 per cent), chromosomal disorders (27.1 per cent), and Mendelian or multifactorial diseases (10.6 per cent) were the main causes of fetal anomaly. More than half (52.9 per cent) of the fetal anomalies were detected by routine ultrasound examination. Forty-two per cent of cystic hygromas were secondary to a chromosomal defect. We stress the importance of a comprehensive fetal and newborn examination to ensure an accurate diagnosis so that subsequently accurate counselling can be provided.

Antenatal diagnosis of ovarian cysts: natural history and therapeutic implications.

A retrospective study from 1980 to 1990 shows 29 ovarian cysts in 27 patients diagnosed by prenatal ultrasound performed between 28 and 38 weeks of gestation. Ten patients underwent surgery, 17 patients were observed with serial ultrasound. Delayed good quality sonograms after spontaneous resolution of the cyst in a selected group of 7 patients showed restoration of a normal ovarian anatomy. The size of the cyst and/or its sonographic characteristics are the 2 main factors for deciding a conservative or a surgical management.

Fetal lobation. An anatomo-ultrasonographic correlation.

Remnants of the fusion of fetal renunculi have been mistaken for renal scars or tumors. We compared anatomic cuts of 24 cadaveric kidneys with fetal lobation (ages ranged from 16 weeks gestation to 49 years) to identical ultrasonographic sections performed in a water bath and to sonograms of healthy persons of similar ages as the cadavers. Fetal lobation was characterized as follows: there were fine, linear demarcations indenting the renal surface, separating normal lobes, consisting of a central pyramid and surrounding cortex. Separate renunculi seen in early fetal life progressively fuse throughout gestation, leaving interlobar grooves. During the third trimester, the renal surface becomes smoother and the interlobar grooves become invisible. One prominent indentation of the renal surface, the interrenuncular junction, incorporates perirenal fat and invaginates the anterior surface of the upper third of the kidney to the hilum and is the most easily visible remnant of fetal lobation. The sharply defined linear remnants of interlobar grooves should not be mistaken for scars, which are wider, less well defined and always associated with loss of renal cortex.

Management of thyroid nodules in children: a 20-year experience.

The medical records and surgical slides of 58 patients with the diagnosis of thyroid nodules (solitary nodule in 50 patients) are reviewed. The most common cause of thyroid nodules in this series is follicular adenoma (27 patients or 46%). A nuclear scan (technetium or radioactive iodine) was performed in 55 patients, of which 40 showed a cold nodule. Twelve of the 40 cold nodules were malignant (30%). However, for solitary nodules the incidence of cancer is 27%. This last figure is significantly greater than the one recently reported by Hung et al (18.5%). Available diagnostic methods are reviewed and the clinical management as derived from our experience is presented.

Multicystic dysplastic kidneys: spontaneous regression demonstrated with US.

In nine neonates, spontaneous regression of a multicystic dysplastic kidney (MCDK) was witnessed by means of repeated ultrasound (US) examinations. In three of these patients, the diagnosis was made in utero. Follow-up examinations at the ages of 3, 5, and 32 weeks post-partum showed what would have been called unilateral agenesis of the affected side if no fetal US study had been done. In the remaining neonates, the diagnosis was made postnatally, and marked reduction in size or complete disappearance of the MCDK was observed on serial US examinations. Three neonates underwent surgical exploration. No trace of a kidney, renal artery, or ureter was found in two. A small MCDK was removed in the third patient. US reveals new features of the natural history of MCDKs. Because malignant transformation of an MCDK is rare and because US provides a means of serial assessment, the authors believe a more conservative, nonsurgical approach is appropriate and recommend an observation time of 1 year before deciding on surgical intervention, unless other problems necessitate surgical removal of the MCDK.

A pseudo-choledocal cyst.

A four-year-old boy presented with a history of intermittent obstructive jaundice. Investigation and surgical exploration revealed an abnormal configuration of the biliary tree which, to our knowledge, has never been otherwise reported.

Urinary tract infection in children. A reappraisal of its radiologic investigation.

In a prospective study, 100 children with either an acute or a previous history of urinary tract infection were investigated by intravenous urography, micturition cystourethrography, and ultrasonography. The results from the three diagnostic modalities were compared: The urinary tracts in 59 patients were normal, and revealed some abnormality in 41. Ultrasonography proved to be superior to intravenous urography in outlining renal contours and in detecting subtle cortical changes secondary to urinary tract infection (such as slight increases in cortical thickness and edema or cortical scarring). The mucosa of the renal pelvis and bladder was more easily assessed by ultrasound than by intravenous urography. Both modalities were "equally" accurate in detecting important congenital malformations of the urinary tract. Ultrasound failed to detect 24 of 28 ureters demonstrating reflux on voiding cystourethrography. We propose that carefully performed abdominal ultrasonography can replace intravenous urography in the initial investigation of urinary tract infection in children. It should be done in association with a radiographic or radionuclide voiding cystogram. Intravenous urography would then become a complementary examination for abnormal or problematic patients.