The "third" dimension in craniofacial surgery

A new method for reconstruction of a three-dimensional surface from a sequence of high-resolution axial CT scans has been developed. This algorithm is realized as a set of computer programs that can operate on commercially available CT scanners or evaluation consoles. The program is both efficient and easy to implement. No operator intervention is required. The images produced simulate photographs of the skull. Frontal, lateral, oblique, bird's eye, worm's eye, and rear views are generated. As with photographs and conventional radiographs, each of these projections uniquely displays specific anatomic details. This method of osseous surface reconstruction is now routinely applied to all patients evaluated for major craniofacial reconstruction at our institution. The images are useful in defining aberrant anatomy, planning surgical procedures, and evaluating the results of such operations. This method replaces an inexact concept in the surgeon's imagination with a three-dimensional image of the craniofacial skeleton.     

Protocol for the "Michigan Awareness Control Study": A prospective, randomized, controlled trial comparing electronic alerts based on bispectral index monitoring or minimum alveolar concentration for the prevention of intraoperative awareness

Background

Prolonged sedation is common in mechanically ventilated patients and is associated with increased morbidity and mortality. We sought to determine the diagnostic value of head computed tomography (CT) in mechanically ventilated patients who remain unresponsive after discontinuation of sedation.

Methods

A retrospective review of adult (age >18 years of age) patients consecutively admitted to the medical intensive care unit of a tertiary care medical center. Patients requiring mechanical ventilation for management of respiratory failure for longer than 72 hours were included in the study group. A group that did not have difficulty with awakening was included as a control.

Results

The median time after sedation was discontinued until a head CT was performed was 2 days (interquartile range 1.375–2 days). Majority (80%) of patients underwent head CT evaluation within the first 48 hours after discontinuation of sedation. Head CT was non-diagnostic in all but one patient who had a small subarachnoid hemorrhage. Twenty-five patients (60%) had a normal head CT. Head CT findings did not alter the management of any of the patients. The control group was similar to the experimental group with respect to demographics, etiology of respiratory failure and type of sedation used. However, while 37% of subjects in the control group had daily interruption of sedation, only 19% in the patient group had daily interruption of sedation (p < 0.05).

Conclusion

In patients on mechanical ventilation for at least 72 hours and who remain unresponsive after sedative discontinuation and with a non-focal neurologic examination, head CT is performed early and is of very limited diagnostic utility. Routine use of daily interruption of sedation is used in a minority of patients outside of a clinical trial setting though it may decrease the frequency of unresponsiveness from prolonged sedation and the need for head CT in patients mechanically ventilated for a prolonged period.     

"Spontaneous" complete remissions in chronic lymphocytic leukemia: report of three cases and review of the literature

"Spontaneous" complete remissions (SCR) are a rare event in chronic lymphocytic leukemia (CLL). In this article, we report three cases of SCR observed in a series of 285 patients followed at a single institution during the last 15 years. SCR was documented by clinical and hematologic data, including bone marrow biopsy, and immune cell markers. A delay of 0.9-1.6 years between "clinical" and "clonal" remission was observed. A review of other cases of SCR in CLL is also performed.     

Results of dynamic endocrine testing of hypothalamic pituitary function in patients with a primary "empty" sella syndrome

A total of 52 patients (38 women, 14 men) with a primary "empty" sella syndrome underwent dynamic endocrine testing consisting of insulin-induced hypoglycaemia and a combined anterior pituitary stimulation test utilizing GnRH and TRH. The diagnosis of an "empty" sella turcica was made on the basis of thin collimation CT reconstructions and in addition either metrizamide cisternography or magnetic resonance (MR) imaging. Only 16 of the patients presented with endocrine problems. Hyperprolactinaemia was the most common endocrine disturbance detected, and was found in 17 individuals. Panhypopituitarism was found in 3 patients. Nine other patients had some degree of partial pituitary insufficiency, but only two of them required replacement therapy. However, 31 patients had no evidence of endocrine dysfunction.     

The "practical mathematics" of recording three-dimensional eye position using scleral coils.

The "gold standard" for recording the three-dimensional rotation of the eye involves placing two coils of wire, embedded in a soft plastic ring, on the sclera of the eye, then placing the subject inside a set of orthogonal oscillating magnetic fields, and using the currents induced in the eye coils to deduce the position of the coil, and hence of the eye, in space. Eye movements are actually eye rotations, which can be described mathematically by a special class of matrices, rotation matrices, or, alternatively, by a rotation vector related to the axis of the rotation. This article deals with the mathematical tools needed to implement the signal processing from such a multifield, dual-coil system and compute the precise rotational movement of the eye. One reason for making such careful measurements is to study an interesting constraint on eye movements, called Listing's law, which expresses ocular torsion, or rotation of the eye about its line of sight, in terms of the direction of gaze. Techniques for experimentally quantitating these constraints are also presented. Following a treatment of the "ideal" case, with coils and eye in perfect alignment, the additional techniques for dealing with various departures from ideality that are almost always encountered experimentally are examined. A final section deals with developing a validation protocol for eye movement analysis techniques using mechanical and computer simulations of eye movements.     

P-12A RETROSPECTIVE AUDIT OF FINE NEEDLE ASPIRATION CYTOLOGY OF PANCREAS

Background:  Fine needle aspiration cytology (FNAC) of pancreas is a widely accepted method of diagnosis of pancreatic mass lesions. We have performed a retrospective analysis of all radiological (CT/ultrasound) and endoscopic ultrasound guided procedures at our institution.
Aim:  (1) To review the results of FNAC of pancreas from January 2000 to April 2006. (2) To calculate the inadequate rate. (3) To account for discrepancies between the cytological and histological diagnoses. (4) To identify any false positive cases if present.
Method:  The results of all pancreatic FNAC reported at our institute from January 2000 to April 2006 were identified from the laboratory system. All results were classified as follows: Inadequate, inconclusive, benign, suspicious and malignant. The results were further categorised depending on whether they were CT/ultrasound guided or EUS guided. The histological diagnosis where available was used as the gold standard and where discrepancies were present the cytological preparations were reviewed.
Results:  Seventy-three patients underwent pancreatic FNAC during the study period. Table 1 illustrates our results.
 

     

7.

Detection of Airway Anomalies in?Pediatric?Patients with Cardiovascular Anomalies with Low Dose Prospective ECG-Gated Dual-Source CT     

Hui Jiao  Zhuodong Xu  Lebin Wu  Zhaoping Cheng  Xiaopeng Ji  Hai Zhong  Chen Meng 《PloS one》2013,8(12)

Objectives

To assess the feasibility of low-dose prospective ECG-gated dual-source CT (DSCT) in detecting airway anomalies in pediatric patients with cardiovascular anomalies compared with flexible tracheobronchoscopy (FTB).

Methods

33 pediatrics with respiratory symptoms who had been revealed cardiovascular anomalies by transthoracic echocardiography underwent FTB and contrast material–enhanced prospective ECG-triggering CT were enrolled. The study was approved by our institution review board and written informed consent was obtained from all patients’ guardian. DSCT examinations were performed to detect cardiovascular abnormalities using weight-adjusted low–dose protocol. Two radiologists independently performed CT image analysis. The FTB reports were reviewed by an experienced pulmonologist. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of DSCT in the detection of airway anomalies were assessed. The tracheobronchial stenoses revealed on FTB were graded. Effective radiation dose was calculated.

Results

Thirty cases were diagnosed with tracheobronchial narrowing and/or abnormality in 33 patients by FTB, while 3 patients had normal FTB findings. Twenty-eight cases were diagnosed with airway anomalies by CT, of which 27 were correct positive. 3 patients with normal findings at CT had findings of tracheobronchial narrowing due to tracheobronchomalacia at inspiration at FTB. Sensitivity and specificity of CT were 90.0% (95% CI: 72.3%, 97.4%) and 66.7% (95% CI: 12.5 %, 98.2 %), respectively. PPV and NPV were 96.4% (95% CI: 79.8 %, 99.8%) and 40.0% (95% CI: 7.3%, 83.0%), respectively. Overall accuracy of DSCT in detecting airway anomalies in pediatrics with cardiovascular anomalies was 87.9% (95% CI: 74.5%, 97.6%). In grading of tracheobronchial stenosis, images from CT correlated closely (r = 0.89) with those of FTB. Mean effective dose was 0.60±0.20 mSv.

Conclusion

In pediatric patients, ECG-triggered CT to evaluate congenital cardiovascular anomalies can also be used to diagnose and characterize fixed airway involvement in relation to the vascular structures.     

8.

Development and validation of a new set-up simulator dedicated to ocular proton therapy at CNAO     

《Physica medica : PM : an international journal devoted to the applications of physics to medicine and biology : official journal of the Italian Association of Biomedical Physics (AIFB)》2021

An Eye Tracking System (ETS) is used at CNAO for providing a stable and reproducible ocular proton therapy (OPT) set-up, featuring a fixation light (FL) and monitoring stereo-cameras embedded in a rigid case. The aim of this work is to propose an ETS set-up simulation algorithm, that automatically provides the FL positioning in space, according to patient-specific gaze direction and avoiding interferences with patient, beam and collimator.Two configurations are provided: one in the CT room for acquiring images required for treatment planning with the patient lying on a couch, and one related to the treatment room with the patient sitting in front of the beam. Algorithm validation was performed reproducing ETS simulation (CT) and treatment (room) set-up for 30 patients previously treated at CNAO. The positioning accuracy of the device was quantified through a set of 14 control points applied to the ETS case and localizable both in the CT volume and in room X-ray images.Differences between the position of ETS reference points estimated by the algorithm and those measured by imaging systems are reported. The corresponding gaze direction deviation is on average 0.2° polar and 0.3° azimuth for positioning in CT room and 0.1° polar and 0.4° azimuth in the treatment room.The simulation algorithm was embedded in a clinically usable software application, which we assessed as capable of ensuring ETS positioning with an average accuracy of 2 mm in CT room and 1.5 mm in treatment room, corresponding to gaze direction deviations consistently lower than 1°.     

9.

Apport de la TEP/TDM au 18F-FDG dans le suivi des endocardites infectieuses sur prothèses valvulaires non opérées     

D. Ouk  S. Delcourt  L. Tessonnier  J.-P. Casalta  G. Habib  O. Mundler  E. Guedj  S. Cammilleri 《Médecine Nucléaire》2018,42(2):59-69

Introduction

Prosthetic valve endocarditis is a diagnostic and therapeutic challenge; ¹⁸F-FDG PET/CT has seen increasing use and has been incorporated in the latest ESC endocarditis guidelines. Follow-up by PET/CT has never been studied. The aim was to study the use of PET/CT to help predicting recurrences after full antibiotic treatment.

Methods

From January 2011 to April 2016, all patients presenting with definite or possible prosthetic valve endocarditis were included and had a PET/CT after admission. After discharge, non-operated patients had a second PET/CT from 6 to 10 weeks after the end of intravenous antibiotic treatment, in addition to clinical and echocardiographic follow-up.

Results

Among 276 patients with prosthetic valve admitted for suspicion of infective endocarditis, 43 of them with an abnormal prosthetic uptake on the first PET/CT had a second PET/CT within a mean period of 67.3 days after the end of intravenous antibiotic treatment. The mean follow-up was 414 days. Five recurrences occurred among the 34 patients with persistent abnormal prosthetic uptake on second PET/CT, there was no recurrence among the nine patients who had no more abnormal prosthetic uptake.

Conclusion

This is the first study to evaluate the potential benefits of PET/CT for medically treated PVE follow-up. All recurrences occurred among patients with persistent abnormal prosthetic uptake on second PET/CT. An unexpected finding was the potential of bone-marrow and splenic uptake evolution, which is underused in IE and showed an interesting potential in the prognosis of these patients.     

10.

Hopi Indians, "cultural" selection,and albinism     

Hedrick PW 《American journal of physical anthropology》2003,121(2):151-156

The incidence of albinism in Hopi Indians has been estimated as approximately 1 in 200 individuals. It has been suggested that "cultural" selection as the result of a mating advantage of males with albinism has been important in the maintenance of this high incidence. To examine this hypothesis quantitatively, a model that includes male-mating advantage, mutation, and viability selection is analyzed. In order to play an important role in the maintenance of the high incidence of albinism, the necessary mating advantage of males with albinism appears unrealistically high. However, if the extent of viability selection against individuals with albinism is not as large as previously assumed, the necessary amount of mating advantage is not as high. Other related aspects are also discussed here, such as the type of albinism in Hopi Indians and its impact, the conditions for a polymorphism with male-mating advantage and viability selection, and the time necessary to change the incidence of albinism either by the relaxation or institution of male-mating advantage.     

11.

The use of multifolded pericranial flaps as "plugs" and "pads"     

Al-Qattan MM 《Plastic and reconstructive surgery》2001,108(2):336-342

Pericranial flaps are thin and, hence, their volumes are small. Therefore, their use for soft-tissue augmentation has not been popular. In this article, the author introduces a new concept: the use of a multifolded pericranial flap as a "plug" or a "pad" for localized contour defects. Eight patients were included in the study. In all cases, an anteriorly based pericranial flap was used, and the flap was folded on itself several times to increase its bulk. The results were satisfactory in all patients. The literature on the topic is reviewed, and the blood supply of pericranial flaps is discussed.     

12.

Survol et bilan de la microchirurgie andrologique “Un baroud d'honneur” pour une cause perdue     

R. Schoysman 《Andrologie》1997,7(3):367-372

The techniques of epididymal surgery and their results are briefly reexposed and compared to the results of assisted procreation with epididymal or testicular sperm. Microsurgery of the epididymis remains a very valuable indication in a selected group of patients leading to the same amount of pregnancies after an average of three attempts by microinsemination of oocytes with epididymal sperm. The expense both for patient and society is much in favour of a surgical approach.     

13.

Metabolic and Receptor Imaging in Patients with Neuroendocrine Tumors: Comparison of Fludeoxyglucose-Positron Emission Tomography and Computed Tomography with Indium in 111 Pentetreotide     

《Endocrine practice》2009,15(6):521-527

ObjectiveTo determine whether positron emission tomography/computed tomography (PET/CT) and indium In 111 pentetreotide, individually or collectively, predict the outcome of patients with neuroendocrine tumors (NETs).MethodsBetween July 31, 2002, and May 4, 2007, 29 patients with previously diagnosed NETs underwent both PET/CT and indium In 111 pentetreotide imaging at our institution. The images were evaluated for the presence of abnormalities. Clinical outcomes were classified as survival without major morbidities, survival with severe complications of disease, or death. Time to outcome was measured in months from the imaging date to outcome. Kaplan-Meier survival curves were calculated in which patient outcome was compared with results on PET/CT and indium In 111 pentetreotide imaging.ResultsOf the 29 patients, 9 had abnormalities on both PET/CT and indium In 111 pentetreotide imaging. Two patients had abnormal findings on PET/CT but normal findings on pentetreotide imaging. In 5 patients, findings were normal on PET/CT but abnormal on pentetreotide imaging. In 13 patients, normal findings were noted on both PET/CT and pentetreotide imaging. Kaplan-Meier analysis demonstrated a significant survival advantage for patients who had normal findings on PET/CT in comparison with abnormal PET/CT findings (P = .01). Patients with normal findings on indium In 111 pentetreotide imaging had a higher but insignificant survival advantage over those with abnormal results on pentetreotide imaging (P = .08).ConclusionFor evaluation of NETs, PET/CT and indium In 111 pentetreotide are complementary. Increased metabolic activity in tumor cells is reflected by abnormalities on PET/CT. Patients who had abnormal PET/CT findings had a generally poorer prognosis and a more rapid clinical deterioration than those with normal PET/CT findings. (Endocr Pract. 2009;15:521-527)     

14.

Normal SUV Values Measured from NaF18- PET/CT Bone Scan Studies     

Aung Zaw Win  Carina Mari Aparici 《PloS one》2014,9(9)

Objectives

Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans.

Methods

A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget’s disease. Eleven studies met all the criteria.

Results

The average normal SUV_max values from 11 patients were: cervical vertebrae 6.84 (range 4.38–8.64), thoracic vertebrae 7.36 (range 6.99–7.66), lumbar vertebrae 7.27 (range 7.04–7.72), femoral head 2.22 (range 1.1–4.3), humeral head 1.82 (range 1.2–2.9), mid sternum 5.51 (range 2.6–8.1), parietal bone 1.71 (range 1.3–2.4).

Conclusion

According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases.     

15.

Computed tomography before lumbar puncture in acute meningitis: a review of the risks and benefits.     

B D Archer 《CMAJ》1993,148(6):961-965

OBJECTIVE: To determine the indications, if any, for routine computed tomography (CT) of the brain before lumbar puncture in the management of acute meningitis. DATA SOURCES: Original research papers, reviews and editorials published in English from 1965 to 1991 were retrieved from MEDLINE. The bibliographies of these articles and of numerous standard texts were examined for pertinent references. A survey of local neurologists was conducted, and legal opinion was sought from the Canadian Medical Protective Association. DATA EXTRACTION: There were no studies directly assessing the risks of lumbar puncture in meningitis; however, all sources were culled for other pertinent information. RESULTS: No cases could be found of patients with acute meningitis deteriorating as a result of lumbar puncture. The neurologic consensus refuted the need for CT in typical acute meningitis. All sources stressed speedy lumbar puncture and the early institution of appropriate antibiotic therapy to minimize the severity of the illness and the risk of death. CONCLUSIONS: (a) There is no evidence to recommend CT of the brain before lumbar puncture in acute meningitis unless the patient shows atypical features, (b) for patients with papilledema the risks associated with lumbar puncture are 10 to 20 times lower than the risks associated with acute bacterial meningitis alone, (c) CT may be necessary if there is no prompt response to therapy for meningitis or if complications are suspected, (d) the inability to visualize the optic fundi because of cataracts or senile miosis is not an indication for CT and (e) there are no Canadian legal precedents suggesting liability if physicians fail to perform CT in cases of meningitis.     

16.

Reliability of Visual Assessment of Non-Contrast CT,CT Angiography Source Images and CT Perfusion in Patients with Suspected Ischemic Stroke     

Tom van Seeters  Geert Jan Biessels  Joris M. Niesten  Irene C. van der Schaaf  Jan Willem Dankbaar  Alexander D. Horsch  Willem P. T. M. Mali  L. Jaap Kappelle  Yolanda van der Graaf  Birgitta K. Velthuis 《PloS one》2013,8(10)

Background and Purpose

Good reliability of methods to assess the extent of ischemia in acute stroke is important for implementation in clinical practice, especially between observers with varying experience. Our aim was to determine inter- and intra-observer reliability of the 1/3 middle cerebral artery (MCA) rule and the Alberta Stroke Program Early CT Score (ASPECTS) for different CT modalities in patients suspected of acute ischemic stroke.

Methods

We prospectively included 105 patients with acute neurological deficit due to suspected acute ischemic stroke within 9 hours after symptom onset. All patients underwent non-contrast CT, CT perfusion and CT angiography on admission. All images were evaluated twice for presence of ischemia, ischemia with >1/3 MCA involvement, and ASPECTS. Four observers evaluated twenty scans twice for intra-observer agreement. We used kappa statistics and intraclass correlation coefficient to calculate agreement.

Results

Inter-observer agreement for the 1/3 MCA rule and ASPECTS was fair to good for non-contrast CT, poor to good for CT angiography source images, but excellent for all CT perfusion maps (cerebral blood volume, mean transit time, and predicted penumbra and infarct maps). Intra-observer agreement for the 1/3 MCA rule and ASPECTS was poor to good for non-contrast CT, fair to moderate for CT angiography source images, and good to excellent for all CT perfusion maps.

Conclusion

Between observers with a different level of experience, agreement on the radiological diagnosis of cerebral ischemia is much better for CT perfusion than for non-contrast CT and CT angiography source images, and therefore CT perfusion is a very reliable addition to standard stroke imaging.     

17.

Value of computed tomography in patients with stroke: Oxfordshire Community Stroke Project.     

P Sandercock  A Molyneux  C Warlow 《BMJ (Clinical research ed.)》1985,290(6463):193-197

The usefulness of computed tomography (CT) was assessed in 325 consecutive patients with a "clinically definite first stroke" from a community stroke register. CT detected five "non-stroke" lesions (two cerebral gliomas, one cerebral metastasis, and two subdural haematomas), a frequency of 1.5%. Five patients were identified with cerebellar haemorrhage, but only one survived long enough to have a CT scan. CT was useful in excluding intracranial haemorrhage as the cause of the stroke in four patients receiving anticoagulants and seven receiving antiplatelet treatment; it showed intracranial haemorrhage in one patient taking aspirin. Forty six patients were in atrial fibrillation at the time of their stroke; four had intracranial haemorrhages and three had haemorrhagic cerebral infarcts. Nineteen patients with presumed ischaemic minor stroke were considered suitable for carotid endarterectomy; CT showed small haemorrhages in two. The CT scan provides very useful information in a minority (up to 28%) of patients with first stroke, who can be selected on quite simple criteria: (a) doubt (usually because of an inadequate history) whether the patient has stroke or a treatable intracranial lesion; (b) the possibility of cerebellar haemorrhage or infarction; (c) the exclusion of intracranial haemorrhage in patients who either are already taking or likely to need antihaemostatic drugs or are being considered for carotid endarterectomy; (d) if the patient deteriorates in a fashion atypical of stroke.     

18.

Diagnostic Accuracy and Clinical Outcomes of ECG-Gated,Whole Chest CT in the Emergency Department     

Kelley R. Branch  Jared Strote  William P. Shuman  Lee M. Mitsumori  Janet M. Busey  Tessa Rue  James H. Caldwell 《PloS one》2013,8(4)

Purpose

The purpose of this study was to assess the diagnostic accuracy and one year prognosis of whole chest, “multiple rule out” CT for coronary artery disease (CAD) in Emergency Department patients.

Methods and Findings

One hundred and two Emergency Department patients at low to intermediate risk of acute coronary syndrome (ACS), pulmonary embolism and/or acute aortic syndrome underwent a research 64 channel ECG-gated, whole chest CT and a standard of care evaluation. Patients were classified with obstructive CAD with either a coronary CT stenosis greater than 50% or a non-evaluable coronary segment. SOC and 3 month follow up data were used to determine an adjudicated clinical diagnosis. The diagnostic ability of obstructive CAD on CT to identify clinical diagnoses was determined. Patients were followed up for 1 year for cardiac events. Seven (7%) patients were diagnosed with ACS. CT sensitivity to detect obstructive CAD in ACS patients was 100% (95% CI 65%, 100%), negative predictive value 100% (96%, 100%), specificity 88% (80%, 94%), and positive predictive value 39% (17%, 64%). Pulmonary embolism and acute aortic syndrome were not identified in any patients. No cardiac events occurred in patients without obstructive CAD over 1 year.

Conclusions

Whole chest CT has high sensitivity and negative predictive value for ACS with excellent one year prognosis in patients without obstructive CAD on CT. The frequency of pulmonary embolism or acute aortic syndrome and the higher radiation dose suggest whole chest CT should be limited to select patients.ClinicalTrials.org #: {"type":"clinical-trial","attrs":{"text":"NCT00855231","term_id":"NCT00855231"}}NCT00855231     

19.

Comparison of positron emission tomography/computed tomography imaging and ultrasound in surveillance of head and neck cancer – The 3-year experience of the ENT Department in Poznan     

Ma?gorzata Wierzbicka  Mariola Popko  Karolina Piskad?o  Rafa? Czepczyński  Aleksandra Stankowska  Tomasz Pi?tka  Miros?aw Dziuk  Witold Szyfter 《Reports of Practical Oncology and Radiotherapy》2011,16(5):184-188

Background

Posttreatment surveillance for the local and regional recurrence of the head and neck squamous cell carcinoma often requires a multimodality techniques that include PET combined with CT, MRI, US.

Aim

The purpose of this study is to compare the diagnostic performance of two imaging techniques (PET/CT and US), and their combined use for the detection of a subclinical regional recurrence in patients after HNSCC treatment.

Materials and methods

83 patients after completion of the HNSCC treatment underwent both US and PET/CT on the mean follow-up of 14 months after initial treatment.

Results

The sensitivity and specificity of PET/CT were 86% and 82%, respectively; US values reached 81% and 87%, respectively. PPV was 79% for PET/CT, and 83% for US. NPV was 89% for PET/CT, and 85% for US. The overall accuracy for PET/CT and US was 84% for both methods.

Conclusion

US could be regarded as complementary to PET/CT as the procedures with highest sensitivity, specificity and NPV for detecting subclinical regional recurrences after HNSCC treatment.     

20.

Dynamics of tear fluid desiccation on a glass surface: a contribution to tear quality assessment     

Leonidas Traipe-Castro  Daniela Salinas-Toro  Daniela López  Mario Zanolli  Miguel Srur  Felipe Valenzuela  Aníbal Cáceres  Héctor Toledo-Araya  Remigio López-Solís 《Biological research》2014,47(1)

Background

Fern-like crystalloids form when a microvolume of tear is allowed to dry out at ambient conditions on a glass surface. Presence of crystalloids in tear “microdesiccates” is used to evaluate patients with Dry-Eye disease. This study aims to examine morphologically the desiccation process of normal tear fluid and to identify changes associated with accelerated tear evaporation. Tear microdesiccates from healthy (Non-Dry Eye) and Dry Eye subjects were produced at ambient conditions. Microdesiccate formation was monitored continuously by dark-field video microscopy. Additionally, accelerated desiccation of tear samples from healthy subjects was conducted under controlled experimental conditions. Particular morphological domains of tear microdesiccates and their progressive appearance during desiccation were compared.

Results

In normal tear microdesiccates, four distinctive morphological domains (zones I, II, III and transition band) were recognized. Stepwise formation of those domains is now described. Experimentally accelerated desiccation resulted in marked changes in some of those zones, particularly involving either disappearance or size reduction of fern-like crystalloids of zones II and III. Tear microdesiccates from Dry Eye subjects may also display those differences and be the expression of a more synchronous formation of microdesiccate domains.

Conclusion

Morphological characteristics of tear microdesiccates can provide insights into the relative rate of tear evaporation.     

Detection of Airway Anomalies in?Pediatric?Patients with Cardiovascular Anomalies with Low Dose Prospective ECG-Gated Dual-Source CT

Objectives

To assess the feasibility of low-dose prospective ECG-gated dual-source CT (DSCT) in detecting airway anomalies in pediatric patients with cardiovascular anomalies compared with flexible tracheobronchoscopy (FTB).

Methods

33 pediatrics with respiratory symptoms who had been revealed cardiovascular anomalies by transthoracic echocardiography underwent FTB and contrast material–enhanced prospective ECG-triggering CT were enrolled. The study was approved by our institution review board and written informed consent was obtained from all patients’ guardian. DSCT examinations were performed to detect cardiovascular abnormalities using weight-adjusted low–dose protocol. Two radiologists independently performed CT image analysis. The FTB reports were reviewed by an experienced pulmonologist. The sensitivity, specificity, positive predictive value (PPV), negative predictive value (NPV), and accuracy of DSCT in the detection of airway anomalies were assessed. The tracheobronchial stenoses revealed on FTB were graded. Effective radiation dose was calculated.

Results

Thirty cases were diagnosed with tracheobronchial narrowing and/or abnormality in 33 patients by FTB, while 3 patients had normal FTB findings. Twenty-eight cases were diagnosed with airway anomalies by CT, of which 27 were correct positive. 3 patients with normal findings at CT had findings of tracheobronchial narrowing due to tracheobronchomalacia at inspiration at FTB. Sensitivity and specificity of CT were 90.0% (95% CI: 72.3%, 97.4%) and 66.7% (95% CI: 12.5 %, 98.2 %), respectively. PPV and NPV were 96.4% (95% CI: 79.8 %, 99.8%) and 40.0% (95% CI: 7.3%, 83.0%), respectively. Overall accuracy of DSCT in detecting airway anomalies in pediatrics with cardiovascular anomalies was 87.9% (95% CI: 74.5%, 97.6%). In grading of tracheobronchial stenosis, images from CT correlated closely (r = 0.89) with those of FTB. Mean effective dose was 0.60±0.20 mSv.

Conclusion

In pediatric patients, ECG-triggered CT to evaluate congenital cardiovascular anomalies can also be used to diagnose and characterize fixed airway involvement in relation to the vascular structures.     

Development and validation of a new set-up simulator dedicated to ocular proton therapy at CNAO

An Eye Tracking System (ETS) is used at CNAO for providing a stable and reproducible ocular proton therapy (OPT) set-up, featuring a fixation light (FL) and monitoring stereo-cameras embedded in a rigid case. The aim of this work is to propose an ETS set-up simulation algorithm, that automatically provides the FL positioning in space, according to patient-specific gaze direction and avoiding interferences with patient, beam and collimator.Two configurations are provided: one in the CT room for acquiring images required for treatment planning with the patient lying on a couch, and one related to the treatment room with the patient sitting in front of the beam. Algorithm validation was performed reproducing ETS simulation (CT) and treatment (room) set-up for 30 patients previously treated at CNAO. The positioning accuracy of the device was quantified through a set of 14 control points applied to the ETS case and localizable both in the CT volume and in room X-ray images.Differences between the position of ETS reference points estimated by the algorithm and those measured by imaging systems are reported. The corresponding gaze direction deviation is on average 0.2° polar and 0.3° azimuth for positioning in CT room and 0.1° polar and 0.4° azimuth in the treatment room.The simulation algorithm was embedded in a clinically usable software application, which we assessed as capable of ensuring ETS positioning with an average accuracy of 2 mm in CT room and 1.5 mm in treatment room, corresponding to gaze direction deviations consistently lower than 1°.     

Apport de la TEP/TDM au 18F-FDG dans le suivi des endocardites infectieuses sur prothèses valvulaires non opérées

Introduction

Prosthetic valve endocarditis is a diagnostic and therapeutic challenge; ¹⁸F-FDG PET/CT has seen increasing use and has been incorporated in the latest ESC endocarditis guidelines. Follow-up by PET/CT has never been studied. The aim was to study the use of PET/CT to help predicting recurrences after full antibiotic treatment.

Hopi Indians, "cultural" selection,and albinism

The incidence of albinism in Hopi Indians has been estimated as approximately 1 in 200 individuals. It has been suggested that "cultural" selection as the result of a mating advantage of males with albinism has been important in the maintenance of this high incidence. To examine this hypothesis quantitatively, a model that includes male-mating advantage, mutation, and viability selection is analyzed. In order to play an important role in the maintenance of the high incidence of albinism, the necessary mating advantage of males with albinism appears unrealistically high. However, if the extent of viability selection against individuals with albinism is not as large as previously assumed, the necessary amount of mating advantage is not as high. Other related aspects are also discussed here, such as the type of albinism in Hopi Indians and its impact, the conditions for a polymorphism with male-mating advantage and viability selection, and the time necessary to change the incidence of albinism either by the relaxation or institution of male-mating advantage.     

The use of multifolded pericranial flaps as "plugs" and "pads"

Pericranial flaps are thin and, hence, their volumes are small. Therefore, their use for soft-tissue augmentation has not been popular. In this article, the author introduces a new concept: the use of a multifolded pericranial flap as a "plug" or a "pad" for localized contour defects. Eight patients were included in the study. In all cases, an anteriorly based pericranial flap was used, and the flap was folded on itself several times to increase its bulk. The results were satisfactory in all patients. The literature on the topic is reviewed, and the blood supply of pericranial flaps is discussed.     

Survol et bilan de la microchirurgie andrologique “Un baroud d'honneur” pour une cause perdue

The techniques of epididymal surgery and their results are briefly reexposed and compared to the results of assisted procreation with epididymal or testicular sperm. Microsurgery of the epididymis remains a very valuable indication in a selected group of patients leading to the same amount of pregnancies after an average of three attempts by microinsemination of oocytes with epididymal sperm. The expense both for patient and society is much in favour of a surgical approach.     

Metabolic and Receptor Imaging in Patients with Neuroendocrine Tumors: Comparison of Fludeoxyglucose-Positron Emission Tomography and Computed Tomography with Indium in 111 Pentetreotide

ObjectiveTo determine whether positron emission tomography/computed tomography (PET/CT) and indium In 111 pentetreotide, individually or collectively, predict the outcome of patients with neuroendocrine tumors (NETs).MethodsBetween July 31, 2002, and May 4, 2007, 29 patients with previously diagnosed NETs underwent both PET/CT and indium In 111 pentetreotide imaging at our institution. The images were evaluated for the presence of abnormalities. Clinical outcomes were classified as survival without major morbidities, survival with severe complications of disease, or death. Time to outcome was measured in months from the imaging date to outcome. Kaplan-Meier survival curves were calculated in which patient outcome was compared with results on PET/CT and indium In 111 pentetreotide imaging.ResultsOf the 29 patients, 9 had abnormalities on both PET/CT and indium In 111 pentetreotide imaging. Two patients had abnormal findings on PET/CT but normal findings on pentetreotide imaging. In 5 patients, findings were normal on PET/CT but abnormal on pentetreotide imaging. In 13 patients, normal findings were noted on both PET/CT and pentetreotide imaging. Kaplan-Meier analysis demonstrated a significant survival advantage for patients who had normal findings on PET/CT in comparison with abnormal PET/CT findings (P = .01). Patients with normal findings on indium In 111 pentetreotide imaging had a higher but insignificant survival advantage over those with abnormal results on pentetreotide imaging (P = .08).ConclusionFor evaluation of NETs, PET/CT and indium In 111 pentetreotide are complementary. Increased metabolic activity in tumor cells is reflected by abnormalities on PET/CT. Patients who had abnormal PET/CT findings had a generally poorer prognosis and a more rapid clinical deterioration than those with normal PET/CT findings. (Endocr Pract. 2009;15:521-527)     

Normal SUV Values Measured from NaF18- PET/CT Bone Scan Studies

Objectives

Cancer and metabolic bone diseases can alter the SUV. SUV values have never been measured from healthy skeletons in NaF18-PET/CT bone scans. The primary aim of this study was to measure the SUV values from normal skeletons in NaF18-PET/CT bone scans.

Methods

A retrospective study was carried out involving NaF18- PET/CT bone scans that were done at our institution between January 2010 to May 2012. Our excluding criteria was patients with abnormal real function and patients with past history of cancer and metabolic bone diseases including but not limited to osteoporosis, osteopenia and Paget’s disease. Eleven studies met all the criteria.

Results

The average normal SUV_max values from 11 patients were: cervical vertebrae 6.84 (range 4.38–8.64), thoracic vertebrae 7.36 (range 6.99–7.66), lumbar vertebrae 7.27 (range 7.04–7.72), femoral head 2.22 (range 1.1–4.3), humeral head 1.82 (range 1.2–2.9), mid sternum 5.51 (range 2.6–8.1), parietal bone 1.71 (range 1.3–2.4).

Conclusion

According to our study, various skeletal sites have different normal SUV values. SUV values can be different between the normal bones and bones with tumor or metabolic bone disease. SUV can be used to quantify NaF-18 PET/CT studies. If the SUV values of the normal skeleton are known, they can be used in the characterization of bone lesions and in the assessment of treatment response to bone diseases.     

Computed tomography before lumbar puncture in acute meningitis: a review of the risks and benefits.

OBJECTIVE: To determine the indications, if any, for routine computed tomography (CT) of the brain before lumbar puncture in the management of acute meningitis. DATA SOURCES: Original research papers, reviews and editorials published in English from 1965 to 1991 were retrieved from MEDLINE. The bibliographies of these articles and of numerous standard texts were examined for pertinent references. A survey of local neurologists was conducted, and legal opinion was sought from the Canadian Medical Protective Association. DATA EXTRACTION: There were no studies directly assessing the risks of lumbar puncture in meningitis; however, all sources were culled for other pertinent information. RESULTS: No cases could be found of patients with acute meningitis deteriorating as a result of lumbar puncture. The neurologic consensus refuted the need for CT in typical acute meningitis. All sources stressed speedy lumbar puncture and the early institution of appropriate antibiotic therapy to minimize the severity of the illness and the risk of death. CONCLUSIONS: (a) There is no evidence to recommend CT of the brain before lumbar puncture in acute meningitis unless the patient shows atypical features, (b) for patients with papilledema the risks associated with lumbar puncture are 10 to 20 times lower than the risks associated with acute bacterial meningitis alone, (c) CT may be necessary if there is no prompt response to therapy for meningitis or if complications are suspected, (d) the inability to visualize the optic fundi because of cataracts or senile miosis is not an indication for CT and (e) there are no Canadian legal precedents suggesting liability if physicians fail to perform CT in cases of meningitis.     

Reliability of Visual Assessment of Non-Contrast CT,CT Angiography Source Images and CT Perfusion in Patients with Suspected Ischemic Stroke

Background and Purpose

Good reliability of methods to assess the extent of ischemia in acute stroke is important for implementation in clinical practice, especially between observers with varying experience. Our aim was to determine inter- and intra-observer reliability of the 1/3 middle cerebral artery (MCA) rule and the Alberta Stroke Program Early CT Score (ASPECTS) for different CT modalities in patients suspected of acute ischemic stroke.

Methods

We prospectively included 105 patients with acute neurological deficit due to suspected acute ischemic stroke within 9 hours after symptom onset. All patients underwent non-contrast CT, CT perfusion and CT angiography on admission. All images were evaluated twice for presence of ischemia, ischemia with >1/3 MCA involvement, and ASPECTS. Four observers evaluated twenty scans twice for intra-observer agreement. We used kappa statistics and intraclass correlation coefficient to calculate agreement.

Results

Inter-observer agreement for the 1/3 MCA rule and ASPECTS was fair to good for non-contrast CT, poor to good for CT angiography source images, but excellent for all CT perfusion maps (cerebral blood volume, mean transit time, and predicted penumbra and infarct maps). Intra-observer agreement for the 1/3 MCA rule and ASPECTS was poor to good for non-contrast CT, fair to moderate for CT angiography source images, and good to excellent for all CT perfusion maps.

Conclusion

Between observers with a different level of experience, agreement on the radiological diagnosis of cerebral ischemia is much better for CT perfusion than for non-contrast CT and CT angiography source images, and therefore CT perfusion is a very reliable addition to standard stroke imaging.     

Value of computed tomography in patients with stroke: Oxfordshire Community Stroke Project.

The usefulness of computed tomography (CT) was assessed in 325 consecutive patients with a "clinically definite first stroke" from a community stroke register. CT detected five "non-stroke" lesions (two cerebral gliomas, one cerebral metastasis, and two subdural haematomas), a frequency of 1.5%. Five patients were identified with cerebellar haemorrhage, but only one survived long enough to have a CT scan. CT was useful in excluding intracranial haemorrhage as the cause of the stroke in four patients receiving anticoagulants and seven receiving antiplatelet treatment; it showed intracranial haemorrhage in one patient taking aspirin. Forty six patients were in atrial fibrillation at the time of their stroke; four had intracranial haemorrhages and three had haemorrhagic cerebral infarcts. Nineteen patients with presumed ischaemic minor stroke were considered suitable for carotid endarterectomy; CT showed small haemorrhages in two. The CT scan provides very useful information in a minority (up to 28%) of patients with first stroke, who can be selected on quite simple criteria: (a) doubt (usually because of an inadequate history) whether the patient has stroke or a treatable intracranial lesion; (b) the possibility of cerebellar haemorrhage or infarction; (c) the exclusion of intracranial haemorrhage in patients who either are already taking or likely to need antihaemostatic drugs or are being considered for carotid endarterectomy; (d) if the patient deteriorates in a fashion atypical of stroke.     

Diagnostic Accuracy and Clinical Outcomes of ECG-Gated,Whole Chest CT in the Emergency Department

Purpose

The purpose of this study was to assess the diagnostic accuracy and one year prognosis of whole chest, “multiple rule out” CT for coronary artery disease (CAD) in Emergency Department patients.

Methods and Findings

One hundred and two Emergency Department patients at low to intermediate risk of acute coronary syndrome (ACS), pulmonary embolism and/or acute aortic syndrome underwent a research 64 channel ECG-gated, whole chest CT and a standard of care evaluation. Patients were classified with obstructive CAD with either a coronary CT stenosis greater than 50% or a non-evaluable coronary segment. SOC and 3 month follow up data were used to determine an adjudicated clinical diagnosis. The diagnostic ability of obstructive CAD on CT to identify clinical diagnoses was determined. Patients were followed up for 1 year for cardiac events. Seven (7%) patients were diagnosed with ACS. CT sensitivity to detect obstructive CAD in ACS patients was 100% (95% CI 65%, 100%), negative predictive value 100% (96%, 100%), specificity 88% (80%, 94%), and positive predictive value 39% (17%, 64%). Pulmonary embolism and acute aortic syndrome were not identified in any patients. No cardiac events occurred in patients without obstructive CAD over 1 year.

Conclusions

Whole chest CT has high sensitivity and negative predictive value for ACS with excellent one year prognosis in patients without obstructive CAD on CT. The frequency of pulmonary embolism or acute aortic syndrome and the higher radiation dose suggest whole chest CT should be limited to select patients.ClinicalTrials.org #: {"type":"clinical-trial","attrs":{"text":"NCT00855231","term_id":"NCT00855231"}}NCT00855231     

Comparison of positron emission tomography/computed tomography imaging and ultrasound in surveillance of head and neck cancer – The 3-year experience of the ENT Department in Poznan

Background

Posttreatment surveillance for the local and regional recurrence of the head and neck squamous cell carcinoma often requires a multimodality techniques that include PET combined with CT, MRI, US.

Aim

The purpose of this study is to compare the diagnostic performance of two imaging techniques (PET/CT and US), and their combined use for the detection of a subclinical regional recurrence in patients after HNSCC treatment.

Materials and methods

83 patients after completion of the HNSCC treatment underwent both US and PET/CT on the mean follow-up of 14 months after initial treatment.

Results

The sensitivity and specificity of PET/CT were 86% and 82%, respectively; US values reached 81% and 87%, respectively. PPV was 79% for PET/CT, and 83% for US. NPV was 89% for PET/CT, and 85% for US. The overall accuracy for PET/CT and US was 84% for both methods.

Conclusion

US could be regarded as complementary to PET/CT as the procedures with highest sensitivity, specificity and NPV for detecting subclinical regional recurrences after HNSCC treatment.     

Dynamics of tear fluid desiccation on a glass surface: a contribution to tear quality assessment

Background

Fern-like crystalloids form when a microvolume of tear is allowed to dry out at ambient conditions on a glass surface. Presence of crystalloids in tear “microdesiccates” is used to evaluate patients with Dry-Eye disease. This study aims to examine morphologically the desiccation process of normal tear fluid and to identify changes associated with accelerated tear evaporation. Tear microdesiccates from healthy (Non-Dry Eye) and Dry Eye subjects were produced at ambient conditions. Microdesiccate formation was monitored continuously by dark-field video microscopy. Additionally, accelerated desiccation of tear samples from healthy subjects was conducted under controlled experimental conditions. Particular morphological domains of tear microdesiccates and their progressive appearance during desiccation were compared.

Results

In normal tear microdesiccates, four distinctive morphological domains (zones I, II, III and transition band) were recognized. Stepwise formation of those domains is now described. Experimentally accelerated desiccation resulted in marked changes in some of those zones, particularly involving either disappearance or size reduction of fern-like crystalloids of zones II and III. Tear microdesiccates from Dry Eye subjects may also display those differences and be the expression of a more synchronous formation of microdesiccate domains.

Conclusion

Morphological characteristics of tear microdesiccates can provide insights into the relative rate of tear evaporation.