Consensus statement on the diagnosis of multiple system atrophy

We report the results of a consensus conference on the diagnosis of multiple system atrophy (MSA). We describe the clinical features of the disease, which include four domains: autonomic failure/urinary dysfunction, parkinsonism and cerebellar ataxia, and corticospinal dysfunction. We set criteria to define the relative importance of these features. The diagnosis of possible MSA requires one criterion plus two features from separate other domains. The diagnosis of probable MSA requires the criterion for autonomic failure/urinary dysfunction plus poorly levodopa responsive parkinsonism or cerebellar ataxia. The diagnosis of definite MSA requires pathological confirmation.

Consensus statement on the diagnosis of multiple system atrophy. American Autonomic Society and American Academy of Neurology

We report the results of a consensus conference on the diagnosis of multiple system atrophy (MSA). We describe the clinical features of the disease, which include four domains: autonomic failure/urinary dysfunction, parkinsonism and cerebellar ataxia, and corticospinal dysfunction. We set criteria to define the relative importance of these features. The diagnosis of possible MSA requires one criterion plus two features from separate domains. The diagnosis of probable MSA requires the criterion for autonomic failure/urinary dysfunction plus poor levodopa responsive parkinsonism or cerebellar ataxia. The diagnosis of definite MSA requires pathological confirmation.

Multiple system atrophy

Although the precise definition of multiple system atrophy has been difficult, a recent consensus in diagnostic criteria for multiple system atrophy has been achieved. This should lead to progress in defining the underlying pathophysiology of the neuroendocrine, autonomic and motor deficits characteristic of multiple system atrophy. Hopefully, these developments will lead to effective treatment.

A DNA probe for the detection of Dicrocoelium dendriticum in ants of Formica spp. and Lasius spp

Repetitive DNA sequences present in the genome of Dicrocoelium dendriticum were identified by hybridization of genomic DNA that had been digested with different restriction enzymes with 32P-labeled genomic D. dendriticum DNA. DNA fragments containing repetitive sequences were isolated from PstI-digested D. dendriticum DNA and were subcloned into a plasmid vector. Plasmids containing repetitive sequences were identified by colony hybridization. One of these plasmids, designated Ddr-IV, was isolated and used as a probe in further studies. Ddr-IV is specific for D. dendriticum since it does not hybridize to DNA isolated from other trematodes. In addition, Ddr-IV was capable of detecting D. dendriticum metacercariae in ants (Formica cunicularia, F. rufibarbis, and Lasius sp.), which act as second intermediate hosts in the parasite's life cycle. Since metacercariae constitute the infectious stage of the parasite for grazing animals, Ddr-IV will provide a useful tool for epidemiology studies of dicrocoeliosis.

Chromosomal imbalances in primary and metastatic pancreatic carcinoma as detected by interphase cytogenetics: basic findings and clinical aspects

To date, cytogenetic studies on pancreatic carcinoma are rare, and little is known about the frequency of cytogenetic aberrations in primary carcinomas compared with metastatic tumour cells. We therefore evaluated the frequency of chromosomal aberrations in 12 primary pancreatic carcinomas and in effusion specimens from 25 patients with pancreatic cancer by using interphase fluorescence in situ hybridization (FISH) and a panel of four centromeric probes. Hyperdiploidy and chromosomal imbalances, predominantly affecting chromosome 8, were a constant finding in metastatic effusion cells, whereas concordant gain of chromosomes or relative loss of chromosome 18 characterized primary pancreatic carcinomas. The potential role of oncogenes located on chromosome 8 for pancreatic cancer progression was further investigated by double-hybridization studies of aneuploid effusion cells with a probe to 8q24 (MYC) and a centromeric probe to chromosome 8, which demonstrated amplification of the MYC oncogene in two of ten cases (20%). Finally, a potential application of basic findings in the clinical setting was tested by searching for micrometastatic cells in effusions from pancreatic cancer patients primarily negative by FISH. Two-colour FISH in combination with extensive screening (>10,000 nuclei) seems to be a useful tool to unequivocally identify micrometastatic cells by demonstrating hyperdiploidy and intranuclear chromosomal heterogeneity.

Vestibular influences on autonomic cardiovascular control in humans

There is substantial evidence that anatomical connections exist between vestibular and autonomic nuclei. Animal studies have shown functional interactions between the vestibular and autonomic systems. The nature of these interactions, however, is complex and has not been fully defined. Vestibular stimulation has been consistently found to reduce blood pressure in animals. Given the potential interaction between vestibular and autonomic pathways this finding could be explained by a reduction in sympathetic activity. However, rather than sympathetic inhibition, vestibular stimulation has consistently been shown to increase sympathetic outflow in cardiac and splanchnic vascular beds in most experimental models. Several clinical observations suggest that a link between vestibular and autonomic systems may also exist in humans. However, direct evidence for vestibular/autonomic interactions in humans is sparse. Motion sickness has been found to induce forearm vasodilation and reduce baroreflex gain, and head down neck flexion induces transient forearm and calf vasoconstriction. On the other hand, studies using optokinetic stimulation have found either very small, variable, or inconsistent changes in heart rate and blood pressure, despite substantial symptoms of motion sickness. Furthermore, caloric stimulation severe enough to produce nystagmus, dizziness, and nausea had no effect on sympathetic nerve activity measured directly with microneurography. No effect was observed on heart rate, blood pressure, or plasma norepinephrine. Several factors may explain the apparent discordance of these results, but more research is needed before we can define the potential importance of vestibular input to cardiovascular regulation and orthostatic tolerance in humans.

[Nuclear magnetic resonance tomography diagnosis of eye motility disorder in high-grade myopia for planning an eye muscle operation]

BACKGROUND

This study was conducted to elucidate the etiology of the acquired, restrictive motility disorder in patients with severe myopia by magnetic resonance imaging (MRI) and intraoperative situs and to verify existing theories about strabismus to develop appropriate methods of eye muscle surgery.

METHODS

Thirty-five patients with unilateral or bilateral high-degree myopia and strabismus, i.e., axial length of the globe averaged 29.4 mm. Multiple coronal, transversal and parasagittal MRI planes were obtained using a Siemens Magnetom (SP 63) 1.5 Tesla MRI scanner (TR = 550 ms, TE = 15 ms; field of view = 21 x 21 cm; pixel matrix = 256 x 512; 3 acquisitions; slice thickness 2 mm; distance factor 0.25). In addition, in a dynamic MRI the patient had to fixate with the less restricted eye for 50 s in different gaze positions. All data were validated by measurements during strabismus surgery. Twenty normal orbits were studied in control MRI scans.

RESULTS

The major MRI finding was dislocation of the lateral rectus in the anterior and midorbital region at an average of 3.4 mm into the temporocaudal quadrant in 13 cases with the typical eso- and hypotropia. This dislocation will reduce the abducting torque of the lateral rectus and create depressing and extorting torques. Two-anatomical explanations are possible: (1) increasing stretch of the lateral rectus because of temporocranial distension of the globe and inability of intermuscular membranes and pulleys to stabilize the path of the lateral rectus; (2) dehiscence of the lateral levator aponeurosis. The restrictive motility disorder was never caused by contact between the enlarged globe and the bones of the orbital apices.

CONCLUSIONS

Until now, an abnormal path of recti EOMs has been known only in Duane's syndrome. Prior to strabismus surgery in patients with high-degree myopia, an orbital MRI scan may be useful. If misalignment of the lateral rectus is detected, the most important aim of eye muscle surgery is to normalize the pathological path of the lateral rectus. MRI morphometry in severe myopia may give additional information on the anatomy of the orbit and biomechanical mechanisms of strabismus. Our findings demonstrate the necessity of fixation-controlled MRI scans.

New approach in strabismus surgery in high myopia

AIMS

To develop appropriate methods of eye muscle surgery in highly myopic patients with esotropia and hypotropia, with respect to the pathological findings in high resolution magnetic resonance imaging (MRI).

METHODS

35 patients with unilateral or bilateral high myopia and strabismus--that is, axial length of the globe averaged 29.4 mm. Multiple coronal, transverse, and parasagittal MRI image planes were obtained using a Siemens Magnetom 1.5 tesla MRI scanner. In 15 patients with a pathological plane of recti extraocular muscles found by MRI and confirmed intraoperatively, a new technique of eye muscle surgery was performed to re-establish the physiological muscle plane. This was checked postoperatively in addition to the measurement of alignment and motility by MRI.

RESULTS

The new MRI finding of a dislocation of the lateral rectus (LR) into the temporocaudal quadrant by 3.4 mm requires new surgical techniques. Only fixing the LR in the physiological meridian at the equator with a silicone loop ('guide pulley') or a non-absorbable suture is a causal therapy. This yields alignment and improves abduction and elevation.

CONCLUSIONS

If the described misalignment of the LR is detected by MRI, a common high dosage recess-resect procedure for esotropia may even aggravate the deviation. The most important aim of eye muscle surgery is to normalise the pathological path of the LR. The restoration of the physiological function of the dislocated LR is remarkable.

Elucidation of restrictive motility in high myopia by magnetic resonance imaging

OBJECTIVE

To elucidate the cause of an acquired, restrictive motility disorder in patients with high myopia.

METHODS

Magnetic resonance imaging (MRI) scans were obtained from 37 patients with high myopia (axial length of globe, 29.4 mm; refractive error, > -15 diopters). Additional dynamic MRI scans were obtained in which the patient fixated in various positions with the less restricted eye for 50 seconds. Twenty normal orbits were studied in control MRI scans.

RESULTS

The path of the lateral rectus, in the anterior and midorbital regions, was displaced downward an average of 3.4 mm in 13 patients with typical esotropia and hypotropia. This mislocation reduces abducting torque of the lateral rectus and creates depressing and extorting moments. The muscle insertions were normal, except where previous strabismus surgery relocated them. Contact between the enlarged globe and the bones of the orbital apices that would cause esotropia was not observed.

CONCLUSIONS

This eye muscle abnormality in patients with high myopia is another strabismus syndrome related to abnormalities of orbital connective tissues and muscle paths. Orbital MRI scans may be useful before strabismus surgery in patients with high myopia. If an abnormal lateral rectus path is found, surgery should be directed to normalize it. Magnetic resonance imaging morphometry in high myopia may give additional information on orbital anatomy and biomechanical mechanisms of strabismus.

The distribution of Lewy bodies in pure autonomic failure: autopsy findings and review of the literature

Pure autonomic failure (PAF; also known as idiopathic orthostatic hypotension or Bradbury-Eggleston syndrome) is an uncommon sporadic disorder, characterized by autonomic failure without other neurological deficits and histopathologically by cell loss in intermediolateral columns and sympathetic ganglia. Few postmortem studies of patients with PAF have been reported in the literature, and none have demonstrated Lewy bodies in distal axons, although this has been described as a feature in Parkinson's disease with autonomic failure. We report a patient with PAF who had orthostatic hypotension and urinary symptoms for 15 years prior to death at the age of 63 years. Postmortem findings included typical and atypical Lewy bodies in the substantia nigra, locus ceruleus, substantia innominata, and sympathetic ganglia, as well as in autonomic axons in the epicardial fat, autonomic nerve fascicles in periadrenal adipose tissue, and autonomic nerves in the muscularis of the urinary bladder. Sites of autonomic nerve involvement correlated with clinical symptomatology, and thus were a valuable observation in the complete autopsy. Systemic autopsy results should be reviewed carefully in patients with PAF, as Lewy bodies in this disease may be seen in distal axons at a great length from their primary cell bodies.

Neurally mediated syncope and syncope due to autonomic failure: differences and similarities

Syncope is a transient loss of consciousness and postural tone caused by a global reduction of blood flow to the brain. Abnormalities in autonomic cardiovascular control can impair blood supply to the brain and produce syncope in two different disorders: autonomic failure and neurally mediated syncope. In autonomic failure, sympathetic efferent activity is chronically impaired so that vasoconstriction is deficient, upon standing blood pressure always falls (i.e., orthostatic hypotension), and syncope or presyncope occurs. Conversely, in neurally mediated syncope, the failure of sympathetic efferent vasoconstrictor traffic (and hypotension) occurs episodically and in response to a trigger. Between syncopal episodes, patients with neurally mediated syncope have normal blood pressure and orthostatic tolerance. This article reviews the characteristics of autonomic failure and describes in more detail the pathophysiology, diagnosis, and treatment of neurally mediated syncope.

Syncope. A neurologist's viewpoint

Syncope is caused by a global reversible reduction of blood flow to the brain. Three hemodynamic abnormalities can cause syncope: (1) a fall in systemic blood pressure because of ineffective control of peripheral vascular resistance, (2) an acute decrease in cardiac output, and (3) an acute increase in cerebrovascular resistance. Complicating the differential diagnosis of syncope are other causes of loss of consciousness, such as seizures, metabolic disorders, and psychiatric disorders, which may simulate syncope.

Syncope: the diagnostic value of head-up tilt testing

To determine the usefulness of prolonged head-up tilt in the diagnosis of neurally mediated syncope, 201 patients with history of syncope of unknown cause and 102 age and gender matched control subjects underwent a 40 minute 60 degrees head-up tilt test. Head-up tilt elicited syncope (i.e., was positive) in 74 of the 201 patients (37%) with a history of unexplained syncope and in only 6 of the 102 controls (6%). The specificity of the test was 100% in patients 60 years of age and older. Symptoms during tilt-induced syncope were identified by the patients as similar to those they had suffered during their spontaneous episodes. All 80 subjects who had tilt-induced syncope recovered without sequelae. The positive predictive value of a positive responses to head-up tilt was 93% and the negative predictive value was 43%. The results indicate that the prolonged head-up tilt test is a very specific procedure of high diagnostic value in patients with a history of unexplained syncope. It is particularly useful in the elderly age groups who have a high incidence of syncope.

[Primary radiotherapy of laryngeal carcinoma. An analysis of the therapeutic results and of the the relapse behavior in 283 patients]

PURPOSE

In the treatment of laryngeal carcinoma definitive radiotherapy results in a similar outcome as surgical treatment in the early stages with a lower morbidity rate and good functional results. In fact no randomized studies exist, so far, and the optimal treatment concept for the different stages is not well defined. The following study analyses retrospectively the treatment results and the recurrence data in patients with a squamous cell carcinoma of the larynx treated with definitive radiotherapy.

PATIENTS AND METHOD

Two hundreds and eighty-three patients with carcinoma of the larynx were treated with radiation therapy in the department of radiology of the LMU München between September 1971 and June 1986. Twenty-six patients (9.2%) were female and 257 (73.1%) male. The median age was 68.5 years, respectively 70 years. All patients had a histologically confirmed squamous cell carcinoma of the larynx. No true subglottic cases were observed. Forty-one (14.5%) tumors were localized supraglottically, 207 (73.1%) glottically. Thirty-five patients had a T4 tumor with glottic and supraglottic involvement. In 147 patients the histopathological grading was evaluable: 32 tumors were classified as G1, 95 as G2, 15 as G3 and 5 as G4. According to the UICC classification of 1979 25 patients had a carcinoma in situ (Tis), 93 patients had a stage T1, 90 stage T2, 40 stage T3 and 35 stage T4. Two hundreds and thirty-three of 283 (82.3%) had no lymph node involvement. In 50 patients clinically a lymph node involvement was observed. 22 patients had a stage N1, 5 patients stage N2 and 23 patients stage N3. An external beam radiation mostly with cobalt-60 was performed with a mean dose of 61.9 Gy.

RESULTS

The 5-years relapse-free survival for the whole group was 61.7%. The probability for "no evidence of disease" (NED) depended on tumor stage and localisation (glottic tumors: Tis/T1 90.5%: T2 59.4%: T3 39.6%: [5-year NED]; supraglottic tumors T1 64.2%: T2/3 28.6%: T4/N3 24.7% [3-year NED]). Other significant prognostic factors besides T-stage were N-stage (NO vs. N1-3: 3-year recurrence-free survival 68% vs. 37.2%, p < 0.001) and histopathologic grading (G1 vs. G3/4: 3-year recurrence-free survival 74% vs. 37.1%, p < 0.01). One hundred and twenty-two (43.1%) patients had a recurrence, which occurred in 75.4% local, in 12.3% loco regional, in 8.2%, with distant metastases and 4.1% combined. In 50 patients with a recurrent disease a salvage therapy was carried out. Thereby 17 patients achieved a complete response.

CONCLUSION

Even for the here described negatively selected patient group with a high median age and multimorbidity, good local control rates could be achieved especially in early stages with definitive radiation therapy. In more advanced stages even in elderly patients a combined surgical-radiotherapeutic treatment should be performed.

[Examinations with the Cardiff Acuity Test]

Recently, a new preferential looking (PL) test has been presented for measuring visual acuity in infants and young children (Cardiff Acuity Test, CAT). The PL target is a schematic vanishing picture composed of isoluminant lines with different spatial orientations. Fifty-three healthy children (4-34 months, group 1), 28 (4-35 months) children at risk for amblyopia due to strabismus (group 2), 19 healthy subjects, and 157 patients (group 3) were tested with the CAT. In group 2 the CAT was compared with the fixation preference test. In group 3 the CAT was compared with a recognition test (Landolt C test). In group 1 the interocular difference of the CAT data was a maximum of 1 dB (70% 0 dB, 30% 1 dB, 1/3 so-called octave). Thus, an interocular difference of > 1 dB was considered to be suggestive of monocular or asymmetrical visual impairment. The maximum value 6/6 was frequently achieved (RE 44%, LE 36%, > 18 months RE 57%, LE 46%). In group 2 only 20% of the monolateral strabismic children showed an interocular difference > 1 dB in the CAT. In group 3 we found significant correlations between the CAT and Landolt acuity. A ratio of about 1.7/1 between CAT and Landolt acuity remained constant in cataract eyes as compared to healthy eyes. In amblyopic eyes due to strabismus this ratio was 3.7/1. Thus, amblyopia was underestimated with the CAT. Without limiting the examination distance, interocular differences > 1 dB in the CAT occurred in 52% of the strabismic amblyopic patients (potential sensitivity). At a distance of 1 m this rate decreased to 22% (real sensitivity). In conclusion, the CAT definitely lacks sensitivity for strabismic amblyopia. The data suggest that the real sensitivity could be improved by using higher spatial frequencies. The use of familiar shapes instead of gratings such as PL targets affects cooperation favorably in 12- to 36-month-old children.

[Objective determination of visual acuity. Improvement of an infrared nystagmography method and comparison with pattern visual evoked potentials]

BACKGROUND

The purpose of this study was to optimize a new nystagmographical method of objective assessment of visual acuity and compare it to an electrophysiological method.

METHODS

In the nystagmographical method motionless brake marks were superimposed on a moving grating pattern, causing suppression of optokinetic nystagmus (OKN). The smallest brake mark that interrupted the OKN was taken as an objective measure for visual acuity (VA). In the electrophysiological method rapid sequences of high-contrast checkerboard patterns of different spatial frequency were presented in a pattern on-off mode in a foveal field. The VEP response function was extrapolated to 0 microV. The objective values of 94 healthy eyes with artificially reduced vision (VA 0.05-2.0) and 314 eyes with pathological reduction of VA due to different etiologies were compared. RESULTS. The selectivity of the nystagmographical method could be improved. With the exception of strabismic amblyopia, the results were closely correlated with the VA. The least VA could be estimated in steps of 0.06, 0.1, 0.2, 0.5 and 0.8.

CONCLUSIONS

The new nystagmographical method yields useful information about the least VA if strabismic amblyopia is excluded.

Discrimination of Neospora caninum from Toxoplasma gondii and other apicomplexan parasites by hybridization and PCR

Neospora caninum is a protozoan parasite which causes neurological problems in dogs and abortion in cattle. As N. caninum is difficult to distinguish morphologically from Toxoplasma gondii, we developed a molecular tool capable of discriminating between the two parasites. Genomic DNA was isolated from in vitro cultured N. caninum tachyzoites and cloned into a plasmid vector. Resulting colonies were subsequently screened by differential hybridization using N. caninum and T. gondii DNA. Two clones were characterized in detail: one clone, termed pNc5, was found to be specific for N. caninum whereas the second clone, pNc1, hybridized with DNA from both parasites. The sequence of pNc5 was determined and different oligonucleotide primers were designed for use in the polymerase chain reaction (PCR). A 944 bp fragment was specifically amplified from N. caninum DNA, but not from DNA extracted from T. gondii or different Sarcocystis species. Positive signals in PCR were obtained with as little as 100 pg parasite template DNA. In addition, dual PCR with primer pairs specific for N. caninum and T. gondii allowed the detection of either parasite in mixed samples.

[Binocular problems caused by aniseikonia and anisophoria after cataract operation]

BACKGROUND

Cataract and refractive surgery aiming at emmetropia, runs the risk to induce binocular problems, e.g. asthenopia or diplopia. If the compatibility concerning binocularity is solely estimated by the calculation of the difference of the retinal image sizes, using intraocular lens formulas or so-called "aniseikonia-programs", important physiological facts are not considered. The actual amount of the aniseikonia, this is the difference of the image size which the patient perceives subjectively, depends on 3 parameters: 1. the optically induced difference of the retinal image size, 2. the spatial density of the retinal photoreceptors and the size of the receptive fields, 3. a possibly existing anomalous retinal correspondence for different retinal image sizes. Besides aniseikonia, the induction of postoperative anisophoria by the required spectacle correction is a considerable aspect. Aniseikonia and anisophoria can cause fusional problems or diplopia because of the mentioned parameters and/or disparity of the retinal images.

CASE REPORT

Cataract surgery should reduce a monolateral high myopia, aiming emmetropia, in axial anisometropia. This resulted in one exemplary case in high aniseikonia with complaints, while in other, comparable patients only a small amount of aniseikonia could be measured by haploscopy. This preoperative refractive situation is comparable to refractive surgery. In a second case with symmetrical myopia of -4 D, binocular problems with diplopia and asthenopia were induced after monolateral cataract surgery by the combination of a moderate aniseikonia and anisophoria.

CONCLUSIONS

To predict the actual postoperative aniseikonia it is necessary for the patient to wear a contact lens preoperatively for a short time to measure the aniseikonia by haploscopy, particularly prior to refractive surgery in axial length ametropia. Due to the different sizes of the receptive fields of the retina, different postoperative aniseikonias may result in spite of similar axial length anisometropia. The individual tolerance of an adult for a postoperatively created anisophoria is hardly predictable. It is obvious that the fusional stress ensued from aniseikonia and anisophoria adds or multiplies. In contrast to horizontal eye movements, vertical eye movements can hardly be compensated by head movements, as the use of bi- or multifocals requires a down gaze of about 30 degrees. Here a height-balance-prism could help.

Adhesion and invasion of bovine endothelial cells by Neospora caninum

Neospora caninum is a recently identified coccidian parasite which was, until 1988, misdiagnosed as Toxoplasma gondii. It causes paralysis and death in dogs and neonatal mortality and abortion in cattle, sheep, goats and horses. The life-cycle of Neospora has not yet been elucidated. The only two stages identified so far are tissue cysts and intracellularly dividing tachyzoites. Very little is known about the biology of this species. We have set up a fluorescence-based adhesion/invasion assay in order to investigate the interaction of N. caninum tachyzoites with bovine aorta endothelial (BAE) cells in vitro. Treatment of both host cells and parasites with metabolic inhibitors determined the metabolic requirements for adhesion and invasion. Chemical and enzymatic modifications of parasite and endothelial cell surfaces were used in order to obtain information on the nature of cell surface components responsible for the interaction between parasite and host. Electron microscopical investigations defined the ultrastructural characteristics of the adhesion and invasion process, and provided information on the intracellular development of the parasites.

Voluntary anonymous linked study of the prevalence of HIV infection and hepatitis C among inmates in a Canadian federal penitentiary for women

OBJECTIVE

To determine the seroprevalence of HIV infection and hepatitis C among inmates of a federal penitentiary for women.

DESIGN

Voluntary, anonymous, linked, point-prevalence study involving testing of blood samples for antibodies to HIV and hepatitis C virus.

PARTICIPANTS

All inmates of the multilevel security federal Prison for Women, Kingston, Ont., who volunteered to participate in the study. Inmates at this long-stay facility are from across Canada.

OUTCOME MEASURE

Seroprevalence rate among participants of antibodies to HIV and hepatitis C virus.

RESULTS

Of the 130 inmates available for study 113 (86.9%) agreed to donate a blood sample. One woman (0.9%) was HIV positive; 45 (39.8%) were positive for hepatitis C antibody.

CONCLUSIONS

It is possible to obtain a high participation rate in a voluntary, anonymous, linked point-prevalence study in a long-stay penitentiary. The HIV seroprevalence rate of 0.9% is lower than that found in studies in provincial (short-stay) prisons. However, the high rate of antibodies to hepatitis C suggests a significant level of risk behaviour, most likely injection drug use, and suggests the potential for a rapid increase in the rate of HIV infection should the number of newly admitted HIV-positive inmates who use injection drugs rise.