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PubMed1997

Prevalence of head-shaking nystagmus in patients according to their diagnostic classification in a dizziness unit.

OBJECTIVE: In a previous publication, the authors documented the prevalence and characteristics of head-shaking nystagmus (HSN) in over 1300 consecutive dizzy patients during formal electronystagmography (ENG) at the combined Otologic Function Unit (OFU) of the Toronto and Mount Sinai Hospitals. This companion study was done to prospectively analyze a subgroup of 300 patients with known clinical diagnoses belonging to the senior author (J.R.). METHODS: The prevalence of HSN in this series of patients with a known diagnosis is prospectively compared to the presence of HSN in a series of normal controls. RESULTS: Results indicate that HSN is seen significantly (p < .05) in those patients with peripheral vestibular dysfunction and that the more globally the peripheral vestibular disorder involves end-organ (i.e., Meniere's) or primary afferent-neuron function (i.e., vestibular neuronitis), the more likely HSN will be present. CONCLUSION: We further comment on the usefulness of the head-shake test and its clinical relevance in the bedside examination of the dizzy patient.

Adolescent↗

PubMed1993

Effectiveness of acoustic reflex threshold criteria in the diagnosis of retrocochlear pathology.

This study examines the acoustic reflex threshold criteria, derived from a large group of patients with cochlear hearing loss proposed by Cohen & Prasher (1992), in order to evaluate their effectiveness in differentiating between cochlear and retro-cochlear lesions. This criterion was tested on 63 patients with surgically confirmed cerebello-pontine angle (CPA) lesions. The false results obtained with this and other criteria were compared. The best balance between the false positive and negative results in the cochlear and retrocochlear group is provided by the criterion of any two adjacent test frequencies (proposed in the companion paper) having an upper limit of 105 dB for hearing below 60 dB and 110 dB for hearing over 60 dB. This study has also singled out the interaural difference criterion as the best diagnostic indicator with the lowest false results with only 1 false negative from 63 CPA cases and 3 false positive cases from 61 cochlear lesions with hearing thresholds over 55 dB.

Acoustic Stimulation↗

PubMed1997

Medical image analysis with fuzzy models.

This paper updates several recent surveys on the use of fuzzy models for segmentation and edge detection in medical image data. Our survey is divided into methods based on supervised and unsupervised learning (that is, on whether there are or are not labelled data available for supervising the computations), and is organized first and foremost by groups (that we know of!) that are active in this area. Our review is aimed more towards 'who is doing it' rather than 'how good it is'. This is partially dictated by the fact that direct comparisons of supervised and unsupervised methods is somewhat akin to comparing apples and oranges. There is a further subdivision into methods for two- and three-dimensional data and/or problems. We do not cover methods based on neural-like networks or fuzzy reasoning systems. These topics are covered in a recently published companion survey by keller et al.

Algorithms↗

PubMed1987

Diseases of quail.

An increasing number and variety of quail are being kept for food production, experimental use, release on hunting preserves, preservation of endangered species, zoological display, and as companion birds. Quail are susceptible to a variety of noninfectious, infectious, and parasitic diseases. Because they are related to chickens and turkeys, many of the diseases in quail are similar to those in poultry. In this article, the diagnostic characteristics of diseases affecting quail are presented along with information on their prevention, control, and treatment.

Animals↗

PubMed1999

Interocular symmetry in nerve fiber layer thickness of normal eyes as determined by polarimetry.

PURPOSE: The existence of asymmetries between the two eyes in number and distribution of nerve fibers may provide an early anatomic indication of glaucomatous disruption if a symmetrical pattern of nerve fibers can be shown in normal eyes. Normal eyes were tested to determine whether a high degree of correspondence of regional nerve fiber layer thickness exists between fellow eyes. METHODS: Nerve fiber layer thickness was inferred from retardation shift measured by a scanning laser polarimeter (Laser Diagnostic Technologies, Inc.) in 40 volunteers without glaucoma or ocular disease (80 eyes). Total thickness and the pattern of nerve fiber thickness over 208 regions was compared between the paired eyes. RESULTS: Inferred nerve fiber layer thickness in companion eyes was highly correlated. Variation of the total nerve fiber thickness was much less between companion eyes than between eyes of different individuals. In terms of regional (i.e., local) interocular correspondence, the measurements in the inferior retina were observed to be highly similar in the two eyes, but a pronounced shift of the location of the superior peak (maximum thickness) in the left eye relative to the right was observed, as were differences between the two eyes in the thickness measurements at the nasal and temporal minima. CONCLUSION: Significant interocular asymmetries were detected in regions other than the interior hemiretina. These interocular asymmetries may reflect previously unrecognized anatomic nerve fiber differences or systematic angular bias in the instrument for one eye relative to the other. In contrast to the regional measures, the measures of total thickness were very similar between companion eyes, suggesting that the assessment of interocular asymmetries of total thickness determined by polarimetry may offer potential for detecting glaucoma.

Adult↗

PubMed1994

Developing a new picture archiving and communication system for the new Osaka University Hospital.

Osaka University Hospital moved into a new hospital building on the suburban Suita campus in October 1993. A newly developed hospital information system, a new radiologic information system and phase I of a completely new Picture Archiving and Communication System (PACS) also began operating. Work began in 1986 on this PACS. The PACS effort has been guided by one working group and two committees during the last 7 years. A survey of the previous diagnostic and image delivery system was performed as part of the preamble to designing an optimal PACS. Extensive analysis and measurement of pre-existing operational conditions was undertaken. These studies and technical research projects are described in a companion paper in this issue. The phase I hardware installation and initial testing were completed in March 1994. Subsequent phases will build incrementally until the completely new, hospital-wide PACS is realized.

Computer Systems↗

PubMed2000

Liquid-based cervical-cell collection with brushes and wooden spatulas: a comparison of 100 conventional smears from high-risk women to liquid-fixed cytocentrifuge slides, demonstrating a cost-effective, alternative monolayer slide preparation method.

Our purpose was to demonstrate that 17.5-mm liquid-based cytocentrifuge circle-slides made using a Hettich (Andreas Hettich Co., Tuttlingen, Germany) cytocentrifuge are at least as efficacious as conventional smears for detecting cervical abnormalities. One hundred conventional smears were collected with cytobrushes and wooden spatulas from high-risk women. Both devices were then placed into CytoRich Red (AutoCyte, Inc., Burlington, NC). Cells were concentrated from CytoRich Red by centrifugation and suspended in CytoRich Yellow. Two 17.5-mm circle-slides were produced, compared to each other in order to test reproducibility of diagnoses between slides, and compared to conventional slides. Sixty-five normals, three ASCUS, three LSIL, and two HSIL matched. Overall, cytocentrifugation yielded 27 additional findings among 25 cases. Also, it downgraded one conventional ASCUS to normal (immature metaplasia and chronic inflammation) and one conventional HSIL to normal (transitional cell metaplasia). Cytocentrifugation of 14 conventional normals afforded four ASCUS and 10 LSIL. Cytocentrifugation of 11 conventional ASCUS afforded nine LSIL and two HSIL (one with AIS). One HSIL + AIS was found with a conventional HSIL. Cytobrushes and wooden spatulas can be used to collect material for liquid-based cervico-vaginal cytology if they are placed into CytoRich Red. Hettich cytocentrifuge slides were more reliable than conventional smears in presenting well-dispersed, sharply imaged cells, affording greater diagnostic sensitivity and certainty. Compared to previous split-sample studies, three different outcomes were noted: 1) the endocervical component was consistently well-represented; 2) AIS was seen more often in liquid-based slides; and 3) the liquid-based slide did not underdiagnose its conventional companion. The liquid-based preparations downgraded one ASCUS to normal and one conventional HSIL to transitional-cell metaplasia. Histology correlation of these two cases agreed with the liquid-based cytology diagnoses, which validates their specificity. These improvements are ascribed to differences in fixation and processing. The low cost, ease of operation, and reusable chambers of the Hettich cytocentrifuge make it a cost-effective liquid-based cytology instrument, especially for small to intermediate-size laboratories. The claims that this paper makes must be proven by additional studies, and test implementation needs to be scrutinized by appropriate regulatory agencies whose standards may vary from country to country. Diagn. Cytopathol. 2000;22:86-91.

Centrifugation↗

PubMedDate not supplied

Assessment of a breath collection technique and portable breath hydrogen monitor for use in cats and dogs.

Until now the use of breath hydrogen testing in companion animal gastroenterology has been limited to academic institutions because of the expense of the equipment. Recently portable breath hydrogen monitors, designed for use in paediatric gastroenterology, have been developed. They may be suitable for use in veterinary medicine as an ancillary diagnostic aid but, before widespread use can be recommended, thorough validation is required. Hydrogen breath tests were conducted in five dogs and four cats, undergoing investigations for small intestinal disease. Breath samples were taken using a closed-flow collection system and concurrently analysed with a commercially available portable breath hydrogen monitor and a previously validated breath hydrogen monitor. In cats, sample collection was troublesome and complete studies could only be performed in two individuals. Good correlation was demonstrated between the readings of both monitors (rs=0.902 and 0.935 for dogs and cats respectively; P<0.002) but agreement was poor with significant under-read from the portable monitor. Our results demonstrate that more studies on validation and the generation of a reference range would be required before the use of this portable hydrogen monitor could be recommended.

Animals↗

PubMed2002

Phenomenology of prepubertal and early adolescent bipolar disorder: examples of elated mood, grandiose behaviors, decreased need for sleep, racing thoughts and hypersexuality.

OBJECTIVE: Children are developmentally incapable of many manifestations of bipolar symptoms described in adults (e.g., children do not "max" out credit cards or have four marriages). To address this issue, our group investigated prepubertal and early adolescent age equivalents of adult mania behaviors. METHODS: Details of the methods appear in the companion article in this issue (Geller et al. 2002a). Subjects had a prepubertal and early adolescent bipolar disorder phenotype (PEA-BP) that was validated by reliable assessment (Geller et al. 2001b), 6-month stability (Geller et al. 2000c), and 1- and 2-year longitudinal diagnostic outcome (Geller et al. 2001a, 2002b). RESULTS: Examples of elation, grandiosity, decreased need for sleep, racing thoughts, and hypersexuality in PEA-BP subjects were compared to examples in prepubertal normal controls and to examples in late teenage/adult-onset mania. Because it is not intuitive that children can be pathologically happy or expansive, sections on guidelines for differentiating normal versus impairing elation and grandiosity are provided. CONCLUSION: Due to the high comorbidity of PEA-BP and attention deficit hyperactivity disorder (ADHD), recognition of mania symptoms that do not overlap with those for ADHD may aid in avoiding both under- and overdiagnosis of child bipolar disorder. A discussion of how "nonoverlapping with ADHD" Diagnostic and Statistical Manual of Mental Disorders (4th ed.) mania symptoms can be useful in the differential diagnosis of irritability is also provided.

Adolescent↗

PubMed2003

The treatment of the "untreatable" patient-revisited.

The limits of medicine have not yet been reached. Numerous human illnesses initially thought to be incurable are reversible under unique and unpredictable individual circumstances. This paper, and the preceding companion publication, describes instances of the successful treatment of patients previously labeled as untreatable, including instances of severe ulcerative colitis and Crohn's disease.

Colitis, Ulcerative↗

PubMed2002

Clinician change detection viewing longitudinal stereophotographs compared to confocal scanning laser tomography in the LSU Experimental Glaucoma (LEG) Study.

PURPOSE: To compare optic nerve head (ONH) surface change detection by confocal scanning laser tomography (CSLT) within the LSU Experimental Glaucoma (LEG) study to expert clinicians viewing the LEG stereophotographs. DESIGN: Experimental study. PARTICIPANTS: Four fellowship-trained glaucoma specialists. METHODS: In the LEG study, six 15 CSLT images (TopSS, Laser Diagnostics Technologies, San Diego, CA) and four 2x optic disc stereophotographs were obtained from both eyes of 12 monkeys on 3 separate days and then every 2 weeks after laser to one eye (study eye) to elevate intraocular pressure. ONH surface change detection within the CSLT images is described in our companion report. In this report, the preliminary study compared change detection by the CSLT multivariate strategy with that of a single clinician viewing stereophotograph pairs on three separate occasions as the "gold standard." The main study compared change detection by three additional clinicians viewing a subset of LEG stereophotograph pairs on three separate occasions with that of the CSLT multivariate strategy as the "gold standard." Clinician change detection was assessed for partial (two of three occasions) or complete (three of three occasions) agreement. Three comparison groups within the main study are emphasized: 44 group A comparisons assessed false-positive change detection (specificity); 38 group B comparisons assessed change detection within 38 instances (11 onset and 27 progression events) of CSLT-detected study eye change; and 30 group C comparisons assessed change detection within 30 instances in which the CSLT failed to detect change in study eyes. MAIN OUTCOME MEASURES: Clinician change detection within each comparison with either partial or complete agreement. RESULTS: Within the main study, intrareading (-.29 to 0.67) and interreading (0.24--0.56) session agreement for each clinician was slight to moderate by kappa test. Good specificity (less than 10% false-positive change detection) was achieved within the 44 group A comparisons by two of the three clinicians, but only when the more stringent criterion (change detection on three of three occasions) was applied. Of the 38 group B comparisons (in which the CSLT detected change), the two clinicians who achieved good specificity in group A failed to detect change in 25 and 16 instances, respectively, using the more stringent (three of three) criterion. Similarly, of the 30 group C comparisons (in which the CSLT failed to detect change), these two clinicians detected change in three and seven instances, respectively, but in only one comparison did they both detect change. CONCLUSIONS: This study provides the first direct evidence that an existing CSLT may reasonably meet or exceed the ONH surface change detection performance of fellowship-trained glaucoma specialists in at least those eyes with good CSLT reproducibility.

Animals↗

PubMed2006

Headache in patients with cervical radiculopathy: a prospective study with selective nerve root blocks in 275 patients.

Since many years we routinely use diagnostic selective nerve root blocks (SNRB) at our department when evaluating patients with cervical radiculopathy. Frequently patients who also presented with headache reported that the headache disappeared when the nerve root responsible for the radicular pain was blocked with local anaesthetics. Headache has been described as a companioning symptom related to cervical radiculopathy but has never before been evaluated with SNRB performed in the lower cervical spine. For this reason we added to our routine an evaluation of the response from the SNRB on headache in patients with cervical radiculopathy. The aim was to describe the frequency of headache in patients with cervical radiculopathy and its response to a selective nerve root block of the nerve root/roots responsible for the radiculopathy. Can nerve root compression in the lower cervical spine produce headache? In this consecutive series of 275 patients with cervical radiculopathy, 161 patients reported that they also suffered from daily or recurrent headache located most often unilaterally on the same side as the radiculopathy. All patients underwent a careful clinical examination by a neurosurgeon and a MRI of the cervical spine. The significantly compressed root/roots, according to the MRI, underwent SNRB with a local anaesthetic. The effect of the nerve root block on the radiculopathy and the headache was carefully noted and evaluated by a physiotherapist using visual analogue scales (VAS) before and after the SNRB. All patients with headache had tender points in the neck/shoulder region on the affected side. Patients with headache graded significantly more limitations in daily activities and higher pain intensity in the neck/shoulder/arm than patients without headache. After selective nerve root block, 59% of the patients with headache reported 50% or more reduction of headache and of these 69% reported total relief. A significant correlation was seen between reduced headache intensity and reduced pain in the neck, shoulder and arm. The result indicates that cervical root compression from degenerative disease in the lower cervical spine producing radiculopathy might also induce headache.

Adult↗

PubMed1995

A retrospective evaluation of adverse reactions to trimethoprim-sulphonamide combinations in dogs and cats.

Adverse reactions to various trimethoprim-sulphonamide (T-S) combinations were studied retrospectively in dogs and cats referred to the Utrecht University Department of Clinical Sciences of Companion Animals during the period 1985-1994. Dermatological and systemic reactions were observed in 19 dogs and 2 cats. Specific histological reaction patterns were seen in 3 dogs with toxic epidermal necrolysis, in 1 dog and 1 cat with erythema multiforme, and in 1 dog with pemphigus foliaceus. Diagnostic criteria used in humans proved to be reliable in dogs and cats as well. Adverse reactions were observed within 7-14 days after administration and were most often due to sulphadiazine (76%) and sulphatroxazole (14%). The incidence of adverse reactions to T-S was 0.25%.

Animals↗

PubMed1996

Diagnosis of leptospirosis: a reemerging disease of companion animals.

Canine leptospirosis has been known since 1899. Widespread use of canine leptospiral vaccines decreased the incidence of infection dramatically and reduced clinical attention to the disease. However, leptospirosis recently has reemerged as an important cause of febrile illness, and hepatic and renal disease in dogs. Feline leptospirosis is rare although the incidence of infection is higher than is recognized. Diagnosis of leptospirosis is difficult and no single diagnostic test provides optimal sensitivity or specificity. A combination of procedures, including serological assays and tests to detect the presence of leptospires in tissues or body fluids, is recommended.

Animals↗

PubMed2003

The PRIME North America randomized double-blind clinical trial of olanzapine versus placebo in patients at risk of being prodromally symptomatic for psychosis. I. Study rationale and design.

The first double-blind placebo-controlled clinical trial of an atypical neuroleptic medication is being conducted in symptomatic treatment-seeking patients meeting new diagnostic criteria for a putative prodromal syndrome. This identifies them as being at high risk for developing psychosis in the near future. The study aims include prevention of psychosis onset and disability, as well as palliation of ongoing symptomatology. This report presents the study rationale and design. Recent studies will be reviewed that have advanced our knowledge about the early course of schizophrenia and our ability to predict onset prospectively, advances that have rendered prodromal intervention research feasible and ethical. The study design has many novel features. It tests for prevention versus delay in psychosis onset, as well as for efficacy and safety in a newly defined clinical population. This has required the development of innovative clinical research assessment instruments and a new operational definition of psychosis onset. The integration of these novel elements into an otherwise typical clinical trial design is detailed. The companion report will address sample recruitment and the clinical phenomenology at baseline of this putative "prodromal" entity.

Adolescent↗

PubMed1997

The diagnostic value of the diatom test for drowning, I. Utility: a retrospective analysis of 771 cases of drowning in Ontario, Canada.

The utility and validity of the diatom test for drowning was studied using a retrospective analysis of 771 cases of drowning mostly from Ontario, Canada, over the period 1977 to 1993. In this article (part one), the utility of the test was assessed using an analysis of test outcomes. In the companion article (part two), the validity of the test was assessed by analyzing the relationship between test outcome and characteristics of diatoms in the bone marrow and samples of putative drowning medium. In the present study, freshwater drownings accounted for 738 of the cases and 33 cases were drownings in bathtubs, pools, or toilets. Diatoms were recovered from the femoral bone marrow of 205 cases (28%) of freshwater drowning and four cases (12%) of domestic water drowning. There was a monthly variation in the frequency of positive test outcomes that could not be explained by seasonal differences in the total number of drownings. However, the monthly variation was strongly correlated with the periodic cycle of diatom blooms that occurs in freshwater. Positive diatom tests were characterized by a limited number of distinctive diatom species per case, and a restricted quantity and size range of diatom frustules. These results indicate that the diatom test for drowning will identify approximately one in three victims of freshwater drowning and may be useful in the assessment of deaths occurring in bathtubs. The correlation of the outcome of the diatom test for drowning with diatom blooms provides further evidence for the reliability of the test.

Bone Marrow↗

PubMed1989

A digital annular array prototype scanner for realtime ultrasound imaging.

The use of annular array transducers in diagnostic ultrasound applications is growing. The development of this equipment raises a number of questions concerning both the role these systems will play in the clinic and how the annular array can be best implemented in an ultrasound scanner. In this paper, we will build on the results of the previous companion paper to describe the development of a 12 element 30 mm diameter 4.5 MHz laboratory prototype scanner. The mechanical probe and probe acoustics are discussed and a unique digital receive beamformer (DRB) and signal processor are described. Focusing down to an f-number (focal length/diameter) of 0.9 is demonstrated. Measured angular beamwidths of 0.62 degrees at -6 dB and 2.8 degrees at -50 dB are in good agreement with theoretical predictions. Images of phantoms and normal volunteers showed exceptional resolution with little variation in the fine speckle texture as a function of depth. The effect of the number of transmit focal zones on image quality is demonstrated.

Equipment Design↗

PubMed1999

Current concepts in the diagnosis and treatment of brain tumours in dogs and cats.

Intracranial tumours occur relatively frequently in dogs, and less commonly in cats. With the availability of computed tomography (CT) and magnetic resonance imaging, more accurate determination of the location and extent of brain tumours in companion animals has become possible. Following these advances in imaging, precise CT-guided stereotactic techniques for both tumour biopsy and intratumoral drug delivery have been developed for use in cats and dogs. Also, tumour identification methods, such as crush preparation examination, have facilitated rapid tumour identification. The use of improved diagnostic techniques has resulted in an increasing demand for effective therapies for brain tumours. While surgical removal and irradiation remain important treatment considerations in the management of brain tumours of cats and dogs, the development of gene therapy strategies for treatment of intracranial tumours offers much promise, although research in this area is still at an early stage.

Animals↗