Investigating the association between variability in sulcal pattern and academic achievement.

Investigating how the brain may constrain academic achievement is not only relevant to understanding brain structure but also to providing insight into the origins of individual differences in these academic abilities. In this pre-registered study, we investigated whether the variability of sulcal patterns, a qualitative feature of the brain determined in-utero and not affected by brain maturation and learning, accounted for individual differences in reading and mathematics. Participants were 97 typically developing 10-year-olds. We examined (a) the association between the sulcal pattern of the IntraParietal Sulcus (IPS) and mathematical ability; (b) the association between the sulcal pattern of the Occipito Temporal Sulcus (OTS) and reading ability; and (c) the overlap and specificity of sulcal morphology of IPS and OTS and their associations with mathematics and reading. Despite its large sample, the present study was unable to replicate a previously observed relationship between the IPS sulcal pattern and mathematical ability and a previously observed association between the left posterior OTS sulcal pattern and reading. We found a weak association between right IPS sulcal morphology and symbolic number abilities and a weak association between left posterior OTS and reading. However, both these associations were the opposite of previous reports. We found no evidence for a possible overlap or specificity in the effect of sulcal morphology on mathematics and reading. Possible explanations for this weak association between sulcal morphology and academic achievement and suggestions for future research are discussed.

A hairy cavity: endoscopic therapy of a presacral recurrence of a complex pilonidal sinus.

BACKGROUND: Recently, minimally invasive techniques to avoid radical excisions of the pilonidal sinus with long-lasting secondary wound healing were developed. We describe a rare case of an intrapelvic, pararectal recurrence of a pilonidal sinus, who was innovatively treated with flexible endoscopy. CASE PRESENTATION: A 43-year-old Caucasian man presented with an intrapelvic, pararectal recurrence of a primarily wide-stretched pilonidal sinus, originally located in the sacrococcygeal region and spreading laterally to the gluteal region and intrapelvic to the presacral area. No connection to the bowel was evident. Up until presentation in the endoscopic department, a total of five attempts of surgical resection were performed, always confirming the diagnosis of a pilonidal sinus. Endoscopic therapy consisted of a combination of debridement, laser ablation and endoscopic vacuum therapy. After completion of APC and VAC therapy, the patient irrigated the abscess cavity for a further 2 weeks with a rinsing syringe. The resulting deep scar at the gluteal fistula was resected after secondary wound healing was completed. Two years after the end of the therapy, no recurrence was evident. CONCLUSION: Flexible endoscopy is, with its multiple therapeutic applications, an effective tool even in very complex inflammatory fistula and abscesses. Correctly indicated, it is with its minimally invasive character an excellent alternative to open surgical approaches.

[Pancreatic anastomosis in operative treatment of chronic pancreatitis]. / Pankreasanastomosen bei operativer Versorgung der chronischen Pankreatitis.

Chronic pancreatitis (CP) is an irreversible, inflammatory process, which is characterized by progressive fibrosis of the pancreas and leads to abdominal pain, endocrine and exocrine insufficiency. Surgical therapy is indicated by the absence of pain relief and local complications. The target of the surgical approach is to relieve the pancreatic and bile ducts and resection of the fibrotic and calcified parenchyma. Drainage procedures, such as the Partington-Rochelle method, are used in patients with isolated congestion of the pancreatic duct without further organ complications, such as inflammatory processes of the pancreatic head; however, patients with CP often have an inflammatory swelling of the pancreatic head. In this case classical pancreatoduodenectomy (PD) or organ-sparing duodenum-preserving pancreatic head resection (DPPHR) with its various techniques (e.g. Beger, Frey, Bern and V­shape) can be applied. Due to similar long-term results PD should be carried out in cases of suspicion or detection of malignancies and DPPHR for treatment of CP.

Videomanometry reveals clinically relevant parameters of swallowing in children.

OBJECTIVE: The aim of this pilot study is to demonstrate the technical and clinical feasibility of videomanometry to assess swallowing in infants and young children presenting with dysphagia. METHODS: We performed videomanometry using a combined solid state catheter and a perfused manometric sleeve assembly in eight patients (2-28 months) presenting at a tertiary care institution with symptoms of dysphagia. Solid state sensors were positioned at the inferior margin of the valleculae and the laryngeal entrance and the upper esophageal sphincter sleeve assembly was positioned across the upper esophageal sphincter. Manometric and radiological data were digitally recorded simultaneously using a manofluoromixer. Liquid bolus swallows were recorded in each patient and different geometric parameters of deglutition were measured. RESULTS: Placement and fixation of the catheter was well tolerated and no adverse effects occurred. The children easily swallowed test boluses as selected during clinical examination. Results indicate that pharyngeal contractility can be evaluated as well as relaxation of the upper esophageal sphincter during swallowing of wet boluses. CONCLUSIONS: Videomanometry in young children is feasible with the limited discomfort of the placement of the catheter. It is a promising technique that will allow more accurate assessment of pediatric oropharyngeal dysphagia.

Development of the orohypopharyngeal cavity in normal infants and young children.

OBJECTIVE: To study the growth of the oropharynx and hypopharynx in infants and young children by measuring the lengths of the segments between nasopharyngeal valve and tongue base, tongue base and arytenoids, and arytenoids and upper esophageal sphincter. These measurements will be used as references for developing manofluoroscopy to study deglutition in infants and young children. PATIENTS AND METHODS: Twenty-three children (14 boys, 9 girls) between birth and 4 years of age were prospectively studied. All children had near normal growth parameters and were free of medical illnesses or other major medical conditions that are known to influence the pharyngeal cavity. Lateral videofluoroscopy was used to assess the pharyngeal structures during breathing. All images were digitally recorded and analyzed using a computer program designed specifically for this study. RESULTS AND CONCLUSIONS: Statistically significant correlations were found between the age or height of the patient and the distance from velopharyngeal valve to tongue base and the distance from tongue base to arytenoids, showing a linear increase of the length of the oro- and hypopharynx with age and patient height. There was no significant difference in the pharyngeal distances between boys and girls. On the basis of these results, a linear regression comparison could be established to define the length of each pharyngeal segment for any age until 4 years and for the 50th percentile of height.

Electrical stimulation reveals complex neuronal input and activation patterns in single myenteric guinea pig ganglia.

The myenteric plexus plays a key role in the control of gastrointestinal motility. We used confocal calcium imaging to study responses to electrical train stimulation (ETS) of interganglionic fiber tracts in entire myenteric ganglia of the guinea pig small intestine. ETS induced calcium transients in a subset of neurons: 52.2% responded to oral ETS, 65.4% to aboral ETS, and 71.7% to simultaneous oral and aboral ETS. A total of 41.3% of the neurons displayed convergence of oral and aboral ETS-induced responses. Responses could be reversibly blocked with TTX (10(-)6 M), demonstrating involvement of neuronal conduction, and by removal of extracellular calcium. omega-Conotoxin (5 x 10(-7) M) blocked the majority of responses and reduced the amplitude of residual responses by 45%, indicating the involvement of N-type calcium channels. Staining for calbindin and calretinin did not reveal different response patterns in these immunohistochemically identified neurons. We conclude that, at least for ETS close to a ganglion, confocal calcium imaging reveals complex oral and aboral input to individual myenteric neurons rather than a polarization in spread of activity.

Integrating images into a central medical information system.

Of the information items that must be easily available to the different actors involved in the care process, radiological images are not the least important. While until recently it was not feasible to include these into the medical information system, this situation has changed. Still, emphasis in PACS (Picture Archiving and Communication Systems) is primarily on the technological aspects. In this paper, in contrast, we stress the importance of integration of images into the overall workflow and into the overall medical record. We do so using illustrations from the PACS project of the University Hospitals Leuven. We briefly indicate that tight integration at the user interface level is needed, and that this requires more than standardized communication between subsystems.

Web-access to a central medical record to improve cooperation between hospital and referring physicians.

We set up Web-access to the central electronic medical record of the University Hospitals Leuven. Purpose was to enable external physicians to more actively participate in the care process as full members of the multidisciplinary treatment team. They get a view on the complete care process in the hospital, and can access results as these become available instead of being provided summary information post factum. This complements traditional electronic exchange between healthcare records. We report on technical setup and results from an extended pilot. We believe that this approach can enrich the discussion on how to provide the "global medical record".

Free cytosolic Ca2+ recordings from myenteric neurones in multilayer intestinal preparations.

The ability to simultaneously monitor different myenteric neurones in a multilayer preparation may enhance our understanding of the enteric nervous system. Longitudinal muscle myenteric plexus preparations were mounted in recording chambers with a coverslip base and loaded with Indo-1-AM. cytosolic Ca2+ concentration ([Ca2+]i); changes were recorded at room temperature with a confocal microscope. In addition to mechanical (pressure-ring) and pharmacological (nifedipine) reduction of muscle contractions, purpose-designed software was developed to reposition regions of interest and avoid artefacts. Confocal scanning permitted optical selection of single cell layers. High K+ depolarization, used to distinguish between excitable and nonexcitable cells, caused a synchronous [Ca2+]i rise in 84.3% of the ganglion cells. Acetylcholine, substance P and serotonin (all at 10(-5) mol L(-1)) induced transient [Ca2+]i changes in subpopulations of myenteric neurones (45.1%, 42.9 and 21.9%, respectively). In addition to immediate responses to agonists, delayed [Ca2+]i changes were also recorded, suggesting the presence of both directly activated and synaptically driven neurones. Functionally identified neurones and other cells in close apposition to the ganglia (interstitial cells of Cajal) could also be studied. This study demonstrates the potential of optical Ca2+ recordings to monitor spread of activity in myenteric neurones and to study their interaction with non-neuronal targets.

Interobserver variations in gross tumor volume delineation of brain tumors on computed tomography and impact of magnetic resonance imaging.

PURPOSE: (1) To assess the interobserver variability of brain tumor delineation on computed tomography (CT). (2) To assess the impact of the addition of magnetic resonance imaging (MRI) information. METHODS: Nine physicians were asked to delineate the gross tumor volume (GTV) of five patients with supratentorial inoperable brain tumors on CT scans and 2 weeks (or more) later on MRIs. The delineations were performed on a computer screen. During delineation on MRI, the registered CT images (without delineation) were displayed on the screen (MRI+CT). RESULTS: A high interobserver variability in GTV delineation on CT is found: the ratio of the largest to the smallest defined volumes varies for the five patients by factors of resp. 2.8, 1.8, 1.8, 1.9 and 1.7. The interobserver variability is as large on MRI+CT as on CT alone (ratio largest/smallest volume: 2.4, 1.7, 1.9, 2.7 and 1.5). Volumes delineated on MRI+CT (mean: 69.6 cm(3)) are larger than on CT alone (mean: 59.5 cm(3)). Residual volumes (volume delineated on one image modality but not on the other) are >0 for CT alone and for MRI+CT. CONCLUSIONS: A large interobserver variability in GTV delineation of brain tumors is demonstrated. The addition of MRI to CT does not reduce interobserver variability. GTVs delineated on MRI+CT are larger than on CT alone, but some volumes are delineated on CT and not on MRI. Therefore, a combination of the two image modalities is recommended for brain tumor delineation for treatment planning.

The relation of CT-determined tumor parameters and local and regional outcome of tonsillar cancer after definitive radiation treatment.

PURPOSE: To investigate the value of CT-derived tumor parameters as predictor of local and regional outcome of tonsillar squamous cell carcinoma treated by definitive radiation therapy. METHODS AND MATERIALS: The pretreatment CT studies of 112 patients with tonsillar squamous cell carcinoma were reviewed. After redigitizing the films, primary and nodal tumor volume was calculated with the summation-of-areas technique. The nodal CT aspect was graded using a 3-point scale (homogenous, inhomogeneous, and necrotic). Mean follow-up time was 33 months. Actuarial statistical analysis of local and regional outcome was done for each of the covariates; multivariate analysis was performed using Cox's proportional hazards model. RESULTS: In the actuarial analysis, CT-determined primary tumor volume was significantly correlated with local recurrence rate (p < 0.05) when all patients were considered, but primary tumor volume did not predict local control within the T2, T3, and T4 category. CT-determined nodal volume was significantly related to regional outcome (p < 0.01), but nodal density was not. Total tumor volume was not significantly related to locoregional outcome (p = 0.1). In the multivariate analysis, the T and N categories were the independent predictors of local and regional outcomes, respectively. CONCLUSION: Compared to other head-and-neck sites, primary and nodal tumor volume have only marginal predictive value regarding local and regional outcome after radiation therapy in tonsillar cancer.

Synaptic transmission induces transient Ca2+ concentration changes in cultured myenteric neurones.

The enteric nervous system controls most of the gastrointestinal functions. We applied confocal microscopy and the Ca2+ indicator Fluo-3 as an optical approach to study synaptic activation in cultures of myenteric neurones. The optical recording of [Ca2+]i (the intracellular Ca2+ concentration) was used to monitor activation, since [Ca2+]i is crucial in the coupling between neuronal excitation and the activation of several intracellular events. Extracellular fibre tract stimulation (2 s, 30 Hz) caused a transient [Ca2+]i rise in a subset of neurones (50%). These transients lasted for 5.2 s (n=36), with an average amplitude of 3.4 +/- 1.3 times the basal concentration. The removal of extracellular Ca2+ (n=15) or the application of 10-6 M tetrodotoxin (n=16) blocked this response. The N-type Ca2+-channel blocker omega-conotoxin (5 x 10 -7M) abolished the [Ca2+]i increase, while blockade of L-type and P/Q type Ca2+ channels had no effect. Single stimuli evoked a [Ca2+]i rise in the processes. omega-conotoxin-sensitive postsynaptic events required repetitive stimulation. Cholinergic blockade did not inhibit the [Ca2+]i rise in all neurones, suggesting that, besides acetylcholine, other neurotransmitters are involved. Optical imaging of [Ca2+]i can be used to study synaptic spread of activation in enteric neuronal circuits expressed in culture.

The contribution of magnetic resonance imaging to the three-dimensional treatment planning of localized prostate cancer.

PURPOSE: To investigate whether the use of transaxial and coronal MR imaging improves the ability to localize the apex of the prostate and the anterior part of the rectum compared to the use of transaxial CT alone, and whether the incorporation of MR could improve the coverage of the prostate by the radiotherapy field and change the volume of rectum irradiated. METHODS AND MATERIALS: Ten consecutive patients with localized prostate carcinoma underwent a CT and an axial and coronal MR scan in treatment position. The CT and MR images were mathematically aligned, and three observers were asked to contour independently the prostate and the rectum on CT and on MR. The interobserver variability of the prostatic apex location and of the delineation of the anterior rectal wall were assessed for each image modality. A dosimetry study was performed to evaluate the dose to the rectum when MR was used in addition to CT to localize the pelvic organs. RESULTS: The interobserver variation of the prostatic apex location was largest on CT ranging from 0.54 to 1.07 cm, and smallest on coronal MR ranging from 0.17 to 0.25 cm. The interobserver variation of the delineation of the anterior rectum on MR was small and constant along the whole length of the prostate (0.09+/-0.02 cm), while for CT it was comparable to that for the MR delineation at the base of the prostate, but it increased gradually towards the apex, where the variation reached 0.39 cm. The volume of MR rectum receiving more than 80% of the prescribed dose was on average reduced by 23.8+/-11.2% from the CT to the MR treatment plan. CONCLUSION: It can be concluded that the additional use of axial and coronal MR scans, in designing the treatment plan for localized prostate carcinoma, improves substantially the localization accuracy of the prostatic apex and the anterior aspect of the rectum, resulting in a better coverage of the prostate and a potential to reduce the volume of the rectum irradiated to a high dose.

Prostate cancer and prostate bed SPECT imaging with ProstaScint: semiquantitative correlation with prostatic biopsy results.

BACKGROUND: ProstaScint (Cytogen Corporation, Princeton, NJ) murine monoclonal antibody imaging is FDA-approved for imaging of prostate cancer patients at high risk for metastatic disease and patients postprostatectomy with a rising serum prostate-specific antigen (PSA) level. ProstaScint is a murine monoclonal antibody which targets prostate-specific membrane antigen (PSMA). PSMA expression is upregulated in primary and metastatic prostate cancer. FDA Cytogen (Princeton, NJ) protocol studies using 111indium-labeled ProstaScint revealed correlation between areas of increased concentration in the prostate and biopsy-proven tumors in patients imaged pretherapy. METHODS: In our study, four transverse, single-photon emission tomography (SPECT) images were isolated and regions of interest were selected and correlated with pretherapy prostate biopsy results. Prostate cancer and normal tissue prostate/muscle background (P/M) ratios were derived, so that postprostatectomy/radiation therapy patients could be evaluated for the presence of residual prostate cancer. Twenty-three pretherapy prostate cancer patients with quadrant/sextant biopsies had SPECT 96-hr 111indium ProstaScint pelvic images. The four transverse 1-cm slices above the midline penile blood pool were chosen, and four to six 27-30-pixel regions of interest were placed over the prostate bed. The background muscle region of interest was placed over the external obturator muscle region. The P/M ratio was calculated and compared to the quadrant/sextant prostatic biopsy result. The same procedure was applied to 17 posttherapy prostate cancer patients with rising PSA. RESULTS: In the 23 pretherapy prostate cancer patients, there was a correlation between the P/M ratio of at least 3.0 in 32 of 35 prostatic cancer biopsy regions, and there was correlation with P/M ratios less than 3.0 in 82 of 89 negative biopsy regions. Seventeen posttherapy patients underwent ProstaScint studies. Six underwent biopsy, with typically one biopsy site per patient. All 6 had P/M ratios greater than 3.0 in the biopsied region. Five out of six biopsies revealed residual prostate cancer. CONCLUSIONS: A prostate/muscle ratio was developed from 111indium ProstaScint regions of interest obtained on 1-cm SPECT transverse slices through the prostate bed in 23 patients preprostatic cancer therapy. A P/M ratio above 3.0 correlated in the majority of positive cases, and a P/M ratio below 3.0 was demonstrated in negative prostatic biopsy cases. The P/M ratio of above 3.0 or below 3.0 also separated those posttherapy prostate cancer patients with rising PSA who had residual prostate carcinoma in the prostate bed.

Laryngeal tumor volume measurements determined with CT: a study on intra- and interobserver variability.

PURPOSE: To investigate the intra- and interobserver variability of computed tomography-based volume measurements of laryngeal tumors. METHODS AND MATERIALS: The volume of 13 laryngeal tumors was repeatedly measured by five independent observers in four different sessions, using the summation-of-areas technique. Mean tumor volume and its standard deviation were calculated for each tumor. Statistical analysis was done with analysis of variance, Spearman rank correlation, and linear regression. RESULTS: Both the effect of the observers (p < 0.0001) and the effect of the session (p < 0.01) on tumor volume was statistically significant. Interobserver variability was the most important component of total variability (89.3%). A significant rank correlation was found between mean volume and standard deviation (p < 0.01); the relationship between mean tumor volume and standard deviation can be described using linear regression [standard deviation = 0.28 volume + 0.35 (R = 0.79)]. CONCLUSION: Total variability in the computed tomography-based measurement of laryngeal tumor volume can be reduced by having the measurements done by a single trained observer.

Size quantification of liver metastases in patients undergoing cancer treatment: reproducibility of one-, two-, and three-dimensional measurements determined with spiral CT.

PURPOSE: To assess the reproducibility of one-, two-, and three-dimensional measurements of the size of liver metastases. MATERIALS AND METHODS: The sizes of 10 liver metastases were determined 200 times: Ten observers measured each lesion by using images obtained at two different CT studies and with five different measurement techniques (maximum diameter, product of diameters, area, volume, and product of three diameters). They repeated each measurement in a separate session. The influence of measurement technique and lesion type (size and morphologic appearance) on measurement reproducibility was assessed. RESULTS: Three-dimensional measurements proved to be as reproducible as one- and two-dimensional measurements. Measurement reproducibility was influenced mainly by the size (P < .0001) and morphologic appearance (P < .01) of the lesions. CONCLUSION: Three-dimensional size measurements obtained with spiral CT are reproducible and could therefore replace the two-dimensional measurements of tumor size currently obtained with follow-up CT studies.

Factors influencing the accuracy of volume measurements in spiral CT: a phantom study.

PURPOSE: The purpose of this study was to investigate the influence of different parameters (object size, shape, orientation, contrast, observer, and window setting) on the accuracy of volume measurements in spiral CT. METHOD: The phantom study consisted of two parts. First, well-circumscribed ellipsoid objects were scanned with conventional and spiral CT. Volumes were determined by two observers using manual contour delineation and summation-of-areas. The influence of object size, CT technique, and observer was assessed. Second, irregularly shaped gingerroots were scanned and the effect of observer, contrast, and orientation was investigated. Also assessed in both parts of the study was the effect of window setting. RESULTS: Spiral CT offered higher accuracy and reproducibility than conventional CT did. The accuracy of volume measurements was mainly determined by the window setting used for image display. Using an "optimized" window center value halfway between object density and background density resulted in overestimation of true object volumes if the number of slices through the object (number of samples) was low. Other factors (contrast, observer-related errors in contour delineation) were less important. CONCLUSIONS: Volume measurements of small objects, obtained with spiral CT and using manual contour delineation, may be grossly erroneous. Major causes of inaccuracy are an inappropriate window center selection and undersampling.

Evaluation of manual vs semi-automated delineation of liver lesions on CT images.

In this paper we compare a semi-automated delineation method with totally manual delineation for area quantification, with respect to efficiency, quality, and intra- and interobserver variability. Liver lesions on 28 CT images were delineated by three observers, twice using completely manual delineation and twice using a semi-automated method. Quantitative comparisons were performed with respect to delineated area and time required for the delineation tasks. Subjective comparisons were performed with respect to efficiency and perceived quality of the semi-automated method. The areas obtained using semi-automated delineation were significantly smaller (11 %) than those obtained using totally manual delineation. Intraobserver and interobserver variability with the semi-automated method were approximately three times lower than with manual delineation. Efficiency of the semi-automated method was subjectively rated favorable, although further improvements are possible. With respect to quality, the semi-automated method was ranked better than the manual method in 73 % of cases.

Using WWW and JAVA for image access and interactive viewing in an integrated PACS.

We start from the observations that (1) potential benefits from PACS can only be realized if PACS and HIS are integrated into a 'multimedia medical information system', and (2) that this also requires integration at the level of the user interface. The user interface should allow integrated interaction with information from different subsystems, of which PACS is one. However, in the real world, different information systems are constructed using different technologies. Moreover, radiological image viewing is a highly interactive task that puts a particular burden on the graphical user interface. We describe our experiences in applying technology emerging around the 'World Wide Web' (WWW) for interactive access to an integrated PACS/HIS. We illustrate the use of Web browsers to access new medical services, touch technologies for interactive access to HIS-PACS information, and emphasize the potential of JAVA applets. We argue that JAVA may become an important tool for providing highly interactive user interfaces to larger multimedia information systems. We discuss Web technology in the general context of HIS/PACS integration.

Preliminary imaging results using In-111 labeled CYT-356 (Prostascint) in the detection of recurrent prostate cancer.

To evaluate whether In-111 capromab pendetide (an antibody conjugate directed to a glycoprotein found primarily on the cell membrane of prostate tissue) radioimmunoscintigraphy can localize residual or metastatic prostatic carcinoma in 15 patients after prostatectomy and lymphadenectomy for prostatic carcinoma with rising serum prostate-specific antigen. One patient with 0.6 ng/ml serum prostate-specific antigen had normal imaging results and 14 patients had scintigraphic evidence of residual prostatic bed or metastatic prostatic carcinoma. Two patients with borderline abnormal bone scans had abnormal activity in the same regions on In-111 capromab pendetide images. All patients had negative radiographic abdominal and pelvic cross-sectional prestudy images, and there were no adverse effects related to In-111 capromab pendetide infusion and little human antimouse antibody response.