ABSTRACT
We demonstrate the deterministic generation of multipartite entanglement based on scalable methods. Four qubits are encoded in ^{40}Ca^{+}, stored in a microstructured segmented Paul trap. These qubits are sequentially entangled by laser-driven pairwise gate operations. Between these, the qubit register is dynamically reconfigured via ion shuttling operations, where ion crystals are separated and merged, and ions are moved in and out of a fixed laser interaction zone. A sequence consisting of three pairwise entangling gates yields a four-ion Greenberger-Horne-Zeilinger state |ψ⟩=(1/sqrt[2])(|0000⟩+|1111⟩), and full quantum state tomography reveals a state fidelity of 94.4(3)%. We analyze the decoherence of this state and employ dynamic decoupling on the spatially distributed constituents to maintain 69(5)% coherence at a storage time of 1.1 sec.
ABSTRACT
We report on the design of a cryogenic setup for trapped ion quantum computing containing a segmented surface electrode trap. The heat shield of our cryostat is designed to attenuate alternating magnetic field noise, resulting in 120 dB reduction of 50 Hz noise along the magnetic field axis. We combine this efficient magnetic shielding with high optical access required for single ion addressing as well as for efficient state detection by placing two lenses each with numerical aperture 0.23 inside the inner heat shield. The cryostat design incorporates vibration isolation to avoid decoherence of optical qubits due to the motion of the cryostat. We measure vibrations of the cryostat of less than ±20 nm over 2 s. In addition to the cryogenic apparatus, we describe the setup required for an operation with 40Ca+ and 88Sr+ ions. The instability of the laser manipulating the optical qubits in 40Ca+ is characterized by yielding a minimum of its Allan deviation of 2.4 â 10-15 at 0.33 s. To evaluate the performance of the apparatus, we trapped 40Ca+ ions, obtaining a heating rate of 2.14(16) phonons/s and a Gaussian decay of the Ramsey contrast with a 1/e-time of 18.2(8) ms.
ABSTRACT
We demonstrate control of the absolute phase of an optical lattice with respect to a single trapped ion. The lattice is generated by off-resonant free-space laser beams, and we actively stabilize its phase by measuring its ac-Stark shift on a trapped ion. The ion is localized within the standing wave to better than 2% of its period. The locked lattice allows us to apply displacement operations via resonant optical forces with a controlled direction in phase space. Moreover, we observe the lattice-induced phase evolution of spin superposition states in order to analyze the relevant decoherence mechanisms. Finally, we employ lattice-induced phase shifts for inferring the variation of the ion position over the 157 µm range along the trap axis at accuracies of better than 6 nm.
ABSTRACT
We demonstrate a method to determine dipole matrix elements by comparing measurements of dispersive and absorptive light ion interactions. We measure the matrix element pertaining to the Ca II H line, i.e., the 4(2)S(1/2)â4(2)P(1/2) transition of (40)Ca(+), for which we find the value 2.8928(43) ea(0). Moreover, the method allows us to deduce the lifetime of the 4(2)P(1/2) state to be 6.904(26) ns, which is in agreement with predictions from recent theoretical calculations and resolves a long-standing discrepancy between calculated values and experimental results.
ABSTRACT
Riley Day syndrome, commonly referred to as familial dysautonomia (FD), is a genetic disease with extremely labile blood pressure owing to baroreflex deafferenation. Chronic renal disease is very frequent in these patients and was attributed to recurrent arterial hypotension and renal hypoperfusion. Aggressive treatment of hypotension, however, has not reduced its prevalence. We evaluated the frequency of kidney malformations as well as the impact of hypertension, hypotension and blood pressure variability on the severity of renal impairment. We also investigated the effect of fludrocortisone treatment on the progression of renal disease. Patients with FD appeared to have an increased incidence of hydronephrosis/reflux and patterning defects. Patients <4 years old had hypertension and normal estimated glomerular filtration rates (eGFR). Patients with more severe hypertension and greater variability in their blood pressure had worse renal function (both, P<0.01). In contrast, there was no relationship between eGFR and the lowest blood pressure recorded during upright tilt. The progression of renal disease was faster in patients receiving fludrocortisone (P<0.02). Hypertension precedes kidney disease in these patients. Moreover, increased blood pressure variability as well as mineralocorticoid treatment accelerate the progression of renal disease. No association was found between hypotension and renal disease in patients with FD.
Subject(s)
Blood Pressure , Dysautonomia, Familial/complications , Kidney/abnormalities , Renal Insufficiency, Chronic/etiology , Adult , Disease Progression , Dysautonomia, Familial/physiopathology , Female , Fludrocortisone/adverse effects , Glomerular Filtration Rate , Humans , MaleABSTRACT
The accurate characterization of eigenmodes and eigenfrequencies of two-dimensional ion crystals provides the foundation for the use of such structures for quantum simulation purposes. We present a combined experimental and theoretical study of two-dimensional ion crystals. We demonstrate that standard pseudopotential theory accurately predicts the positions of the ions and the location of structural transitions between different crystal configurations. However, pseudopotential theory is insufficient to determine eigenfrequencies of the two-dimensional ion crystals accurately but shows significant deviations from the experimental data obtained from resolved sideband spectroscopy. Agreement at the level of 2.5×10(-3) is found with the full time-dependent Coulomb theory using the Floquet-Lyapunov approach and the effect is understood from the dynamics of two-dimensional ion crystals in the Paul trap. The results represent initial steps towards an exploitation of these structures for quantum simulation schemes.
ABSTRACT
PURPOSE: The aim of this study was to evaluate the effect of inferior oblique muscle recession (IOR) in children with pure unilateral strabismus sursoadductorius (so-called congenital superior oblique palsy, CSOP) operated before age 11 years. PATIENTS AND METHODS: A retrospective study of IOR in children with unilateral CSOP and surgery before age 11 years was undertaken. In most cases, recession and anteroposition of the anterior part of the inferior oblique tendon next to the lateral edge of the inferior rectus muscle was performed without fixation of the posterior part of the tendon. Main outcome measures were change in abnormal head tilt, change in vertical deviation, both in straight and contralateral side gaze, and evaluation of squint angles. RESULTS: Between 1997 and 2007, 36 consecutive children (aged 2 -10 years; 27 boys, 9 girls) received IOR for unilateral CSOP. The dose of IOR ranged between 6 and 12 mm. Vertical deviation in straight and contralateral gaze was reduced from median 5° (range 0 - 11°) and 12° (3 - 20°) to 0° (-2 - 8°) and 1° (-5 - 13°), respectively. Abnormal head tilt towards the contralateral shoulder was reduced from median 10° (0 - 20°) to 0° (-2,5 - 10°). Three children (8 %) received further extraocular muscle surgery within 2 years, one because of persistent hyperdeviation, and two because of consecutive hypodeviation of the operated eye. CONCLUSIONS: The results indicate that IOR with fixation of only the anterior part of the inferior oblique to the sclera is an effective treatment for strabismus sursoadductorius/CSOP in children. Undercorrection into a residual, well compensated stage is a satisfying result. Both overcorrection and elevation deficiency were rare.
Subject(s)
Strabismus/congenital , Strabismus/surgery , Trochlear Nerve Diseases/congenital , Trochlear Nerve Diseases/surgery , Child , Child, Preschool , Female , Humans , Male , Oculomotor Muscles/surgery , Postoperative Complications/diagnosis , Postoperative Complications/surgery , Reoperation , Retrospective Studies , Strabismus/diagnosis , Tendons/surgery , Treatment Outcome , Trochlear Nerve Diseases/diagnosisABSTRACT
Leukoencephalopathy and autonomic dysfunction have been described in individuals with very low serum B(12) levels (<200 pg/ml), in addition to psychiatric changes, neuropathy, dementia and subacute combined degeneration. Elevated homocysteine and methylmalonic acid levels are considered more sensitive and specific for evaluating truly functional B(12) deficiency. A previously healthy 62-year-old woman developed depression and cognitive deficits with autonomic dysfunction that progressed over the course of 5 years. The patient had progressive, severe leukoencephalopathy on multiple MRI scans over 5 years. Serum B(12) levels ranged from 267 to 447 pg/ml. Homocysteine and methylmalonic acid levels were normal. Testing for antibody to intrinsic factor was positive, consistent with pernicious anaemia. After treatment with intramuscular B(12) injections (1000 µg daily for 1 week, weekly for 6 weeks, then monthly), she made a remarkable clinical recovery but remained amnesic for major events of the last 5 years. Repeat MRI showed partial resolution of white matter changes. Serum B(12), homocysteine and methylmalonic acid levels are unreliable predictors of B(12)-responsive neurologic disorders, and should be thoroughly investigated and presumptively treated in patients with unexplained leukoencephalopathy because even long-standing deficits may be reversible.
Subject(s)
Autonomic Nervous System Diseases/drug therapy , Cognition Disorders/drug therapy , Depressive Disorder/drug therapy , Leukoencephalopathies/drug therapy , Vitamin B 12 Deficiency/drug therapy , Vitamin B 12/administration & dosage , Vitamin B 12/blood , Autoantibodies/blood , Autonomic Nervous System Diseases/blood , Brain/drug effects , Brain/pathology , Cognition Disorders/blood , Depressive Disorder/blood , Drug Therapy, Combination , Female , Homocysteine/blood , Humans , Intrinsic Factor/immunology , Leukoencephalopathies/blood , Magnetic Resonance Imaging , Mental Status Schedule/statistics & numerical data , Methylmalonic Acid/blood , Middle Aged , Neurologic Examination/drug effects , Psychometrics , Vitamin B 12 Deficiency/blood , Vitamin D/administration & dosageABSTRACT
HISTORY AND CLINICAL FINDINGS: A 55-year-old woman was referred to our hospital with signs of cerebral ischaemia i. e. dysarthria and weakness of the buccal branch of the facial nerve. Additionally the patient reported symptoms of heart failure NYHA class II. Six months earlier the patient also had visual disturbances. Magnetic resonance imaging (MRI) had shown ischaemic lesions. INVESTIGATIONS: A recent MRI confirmed the suspected diagnosis of ischaemia in the territory supplied by the left middle cerebral artery. The echocardiography was characterized by a reduced left ventricular ejection fraction (25 %) due to isolated ventricular non-compaction (IVNC). TREATMENT AND COURSE: The patient was treated with a combination therapy including ACE-inhibitors and diuretics. An oral anticoagulation was recommended as secondary prophylaxis. At the time of discharge the patient had no residual neurological deficits. CONCLUSION: Isolated ventricular non-compaction is a rare type of cardiomyopathy. Possible manifestations include systemic embolic events, arrhythmias and heart failure. Echocardiography is the investigation of choice in identifying characteristic changes.
Subject(s)
Echocardiography , Ventricular Dysfunction, Left/diagnosis , Angiotensin-Converting Enzyme Inhibitors/therapeutic use , Anticoagulants/therapeutic use , Diuretics/therapeutic use , Drug Therapy, Combination , Echocardiography, Doppler, Color , Female , Heparin, Low-Molecular-Weight/therapeutic use , Humans , Infarction, Middle Cerebral Artery/diagnosis , Isolated Noncompaction of the Ventricular Myocardium , Magnetic Resonance Imaging , Middle Aged , Mitral Valve Insufficiency/diagnosis , Mitral Valve Insufficiency/drug therapy , Phenprocoumon/therapeutic use , Ventricular Dysfunction, Left/drug therapyABSTRACT
BACKGROUND: A consensus conference on multiple system atrophy (MSA) in 1998 established criteria for diagnosis that have been accepted widely. Since then, clinical, laboratory, neuropathologic, and imaging studies have advanced the field, requiring a fresh evaluation of diagnostic criteria. We held a second consensus conference in 2007 and present the results here. METHODS: Experts in the clinical, neuropathologic, and imaging aspects of MSA were invited to participate in a 2-day consensus conference. Participants were divided into five groups, consisting of specialists in the parkinsonian, cerebellar, autonomic, neuropathologic, and imaging aspects of the disorder. Each group independently wrote diagnostic criteria for its area of expertise in advance of the meeting. These criteria were discussed and reconciled during the meeting using consensus methodology. RESULTS: The new criteria retain the diagnostic categories of MSA with predominant parkinsonism and MSA with predominant cerebellar ataxia to designate the predominant motor features and also retain the designations of definite, probable, and possible MSA. Definite MSA requires neuropathologic demonstration of CNS alpha-synuclein-positive glial cytoplasmic inclusions with neurodegenerative changes in striatonigral or olivopontocerebellar structures. Probable MSA requires a sporadic, progressive adult-onset disorder including rigorously defined autonomic failure and poorly levodopa-responsive parkinsonism or cerebellar ataxia. Possible MSA requires a sporadic, progressive adult-onset disease including parkinsonism or cerebellar ataxia and at least one feature suggesting autonomic dysfunction plus one other feature that may be a clinical or a neuroimaging abnormality. CONCLUSIONS: These new criteria have simplified the previous criteria, have incorporated current knowledge, and are expected to enhance future assessments of the disease.
Subject(s)
Autonomic Nervous System Diseases/diagnosis , Brain/pathology , Cerebellar Ataxia/diagnosis , Multiple System Atrophy/diagnosis , Parkinsonian Disorders/diagnosis , Autonomic Nervous System Diseases/physiopathology , Basal Ganglia/pathology , Basal Ganglia/physiopathology , Brain/physiopathology , Cerebellar Ataxia/physiopathology , Cerebellum/pathology , Cerebellum/physiopathology , Diagnosis, Differential , Inclusion Bodies/metabolism , Inclusion Bodies/pathology , Multiple System Atrophy/physiopathology , Parkinsonian Disorders/physiopathology , alpha-Synuclein/metabolismABSTRACT
OBJECTIVE: To perform an evidence-based review of the safety and efficacy of botulinum neurotoxin (BoNT) in the treatment of autonomic and urologic disorders and low back and head pain. METHODS: A literature search was performed including MEDLINE and Current Contents for therapeutic articles relevant to BoNT and the selected indications. Authors reviewed, abstracted, and classified articles based on the quality of the study (Class I-IV). Conclusions and recommendations were developed based on the highest level of evidence and put into current clinical context. RESULTS: The highest quality literature available for the respective indications was as follows: axillary hyperhidrosis (two Class I studies); palmar hyperhidrosis (two Class II studies); drooling (four Class II studies); gustatory sweating (five Class III studies); neurogenic detrusor overactivity (two Class I studies); sphincter detrusor dyssynergia in spinal cord injury (two Class II studies); chronic low back pain (one Class II study); episodic migraine (two Class I and two Class II studies); chronic daily headache (four Class II studies); and chronic tension-type headache (two Class I studies). RECOMMENDATIONS: Botulinum neurotoxin (BoNT) should be offered as a treatment option for the treatment of axillary hyperhidrosis and detrusor overactivity (Level A), should be considered for palmar hyperhidrosis, drooling, and detrusor sphincter dyssynergia after spinal cord injury (Level B), and may be considered for gustatory sweating and low back pain (Level C). BoNT is probably ineffective in episodic migraine and chronic tension-type headache (Level B). There is presently no consistent or strong evidence to permit drawing conclusions on the efficacy of BoNT in chronic daily headache (mainly transformed migraine) (Level U). While clinicians' practice may suggest stronger recommendations in some of these indications, evidence-based conclusions are limited by the availability of data.
Subject(s)
Autonomic Nervous System Diseases/drug therapy , Botulinum Toxins/administration & dosage , Neuromuscular Blocking Agents/administration & dosage , Pain/drug therapy , Autonomic Nervous System Diseases/physiopathology , Clinical Trials as Topic/statistics & numerical data , Evidence-Based Medicine , Humans , Hyperhidrosis/drug therapy , Low Back Pain/drug therapy , Pain/physiopathology , Urinary Bladder, Neurogenic/drug therapyABSTRACT
BACKGROUND: Presenting the same histological diagnosis, multiple myeloma (MM) shows a large genomic variety, resulting in variable times of overall survival. MATERIALS AND METHODS: To investigate major cytogenetic categories (any 14q-translocation, t(11;14), t(4;14), 13q-deletions, 17p-deletions) and their clinical consequences in MM after a pre-existing monoclonal gammopathy (MM post-MGUS), we performed a comparative analysis of 41 patients with MM post-MGUS and 287 patients with unknown prior history MM (U-MM). RESULTS: In MM post-MGUS, a t(11;14) was found to be more frequent than in U-MM (24% vs. 14%) and it was associated with significantly shortened survival (24 months vs. 70 months in U-MM; P = 0.01). MM post-MGUS was further characterized by a higher frequency of 13q-deletions only (absence of all other specific abnormalities; 28% vs. 12% in U-MM; P = 0.02). A 13q-deletion only was an indicator of long survival in MM post-MGUS (median not yet reached) as opposed to U-MM (median survival, 29 months; P = 0.001). 17p-deletions were infrequent in MM post-MGUS (3% vs. 16% in U-MM; P = 0.04). Survival times for patients with t(4;14) and/or 17p-deletions and other abnormalities were similar in both MM patient cohorts. CONCLUSIONS: Our data suggest that t(11;14) and 13q-deletions have distinct prognostic implications in the context of MM post-MGUS.
Subject(s)
Chromosome Deletion , Monoclonal Gammopathy of Undetermined Significance/complications , Multiple Myeloma/genetics , Translocation, Genetic , Adult , Aged , Aged, 80 and over , Chromosomes, Human, Pair 11 , Chromosomes, Human, Pair 14 , Female , Humans , In Situ Hybridization, Fluorescence , Male , Middle Aged , Multiple Myeloma/complications , Prognosis , Survival RateABSTRACT
Little is known about tumor-related prognostic factors, in particular specific chromosomal abnormalities, in young patients with multiple myeloma (MM). We therefore investigated the chromosomal pattern by interphase fluorescence in situ hybridization (chromosomes 13q14, 14q32-translocations, chromosomes associated with hyperdiploidy) in 38 young patients with MM (age <45 yr) and compared the results with those observed in 69 patients with intermediate age (45-70 yr) and 64 elderly patients (age >70 yr). All chromosomal patterns were not significantly different between the three age cohorts. Similarly, standard MM parameters were equally distributed between these MM patient populations. However, survival by the International Staging System (ISS) for MM revealed marked differences between stage I/II (median survival not yet reached) and stage III (23.4 months; P < 0.0003) among young MM patients. A significant survival difference between ISS-stage I/II and ISS-stage III patients was also noted in the intermediate age group (median 65.4 months vs. 24.6 months; P = 0.0009). However, this difference disappeared among elderly MM patients (39.6 months in ISS-stage I/II vs. 32 months in ISS-stage III patients; P = 0.94), but it was unrelated to the cytogenetic pattern. Our results indicate that MM in young patients does not represent a distinct biologic entity, and that short survival of younger MM patients at ISS-stage III is independent of the molecular cytogenetic pattern.
Subject(s)
Chromosome Aberrations , Multiple Myeloma/genetics , Multiple Myeloma/pathology , Adult , Age Distribution , Aged , Aged, 80 and over , Humans , In Situ Hybridization, Fluorescence , Internationality , Interphase , Middle Aged , Neoplasm Staging/standards , Prognosis , Survival RateABSTRACT
Studies of bortezomib in patients with relapsed multiple myeloma (MM) suggested that bortezomib may be active even in the presence of adverse prognostic factors. We therefore evaluated 62 patients with relapsed/refractory MM who were treated with single-agent bortezomib, and addressed the question whether or not the negative prognostic impact of unfavorable cytogenetic abnormalities may be overcome by bortezomib. By interphase fluorescence in situ hybridization (FISH), a deletion of chromosome 13q14 [del(13q14)] was present in 33 patients (53%). Overall response rates to bortezomib were similar in patients with and without del(13q14) (45 versus 55%; P=0.66), and rates of complete remission (CR) near CR were also not different between the two patient populations (18 versus 14%). Three patients had a t(4;14)(p16;q32) in addition to del(13q14), and all of them had a >50% paraprotein reduction. Median duration of response was 12.3 months in patients with del(13q14) compared with 9.3 months in patients with normal 13q-status (P=0.25), and survival was also not different between the two patient populations. Patients not benefiting from single-agent bortezomib were characterized by the combined presence of a del(13q14) and low serum albumin (median survival 4.6 months). Our results provide evidence for remarkable activity of bortezomib in MM with del(13q14). Patients who do not respond to bortezomib and consecutively have short time to treatment failure and overall survival can be identified by low serum albumin in addition to del(13q14) and should be considered for bortezomib combinations.
Subject(s)
Antineoplastic Agents/therapeutic use , Boronic Acids/therapeutic use , Chromosome Deletion , Chromosomes, Human, Pair 13 , Multiple Myeloma/drug therapy , Pyrazines/therapeutic use , Adult , Aged , Bortezomib , Cohort Studies , Humans , In Situ Hybridization, Fluorescence , Middle Aged , Multiple Myeloma/genetics , Multiple Myeloma/mortality , Multiple Myeloma/pathology , Prognosis , Recurrence , Survival AnalysisABSTRACT
In the 1950s it was found that an artificial aminoacid, 3,4-threo-dihydroxyphenylserine (DOPS), was converted to norepinephrine (NE) in a single step by the enzyme L-aromatic amino acid decarboxylase (AADC), bypassing the need for the rate limiting enzyme dopamine beta hydroxylase. Trying to replicate the success of dihydroxyphenylalanine (DOPA) in the treatment of Parkinson disease, treatment with DOPS was attempted in patients with autonomic failure who have impaired NE release. DOPS improved orthostatic hypotension in patients with familial amyloid polyneuropathy, congenital deficiency of dopamine beta hydroxylase, pure autonomic failure and multiple system atrophy. DOPS pressor effect is due to its conversion to NE outside the central nervous system because concomitant administration of carbidopa, an inhibitor of AADC that does not cross the blood-brain barrier, blunted both the increase in plasma NE and the pressor response. DOPS pressor response is not dependent on intact sympathetic terminals because its conversion to NE also occurs in non-neuronal tissues.
Subject(s)
Antiparkinson Agents/antagonists & inhibitors , Antiparkinson Agents/pharmacology , Blood Pressure/drug effects , Carboxy-Lyases/antagonists & inhibitors , Droxidopa/antagonists & inhibitors , Droxidopa/pharmacology , Enzyme Inhibitors/pharmacology , Animals , Antiparkinson Agents/pharmacokinetics , Antiparkinson Agents/therapeutic use , Droxidopa/pharmacokinetics , Droxidopa/therapeutic use , Humans , Neurotransmitter Agents/metabolismABSTRACT
Podosphaera pannosa, the causal agent of rose powdery mildew, hampers the production of cut roses throughout the world. A major tool to control this disease is the use of resistant plant material. Single resistance genes, like Rpp1, may be overcome within a few years by high risk pathogens like powdery mildews. Durable resistance could be achieved using quantitative resistances. Here we describe mapping of QTLs for resistance to P. pannosa in six different environments (artificial and natural infections in the greenhouse over 3 years and natural infections in the field over 2 years). AFLPs, RGAs and other marker types were used to construct an integrated linkage map for the diploid population 97/7 containing 233 markers. In a selective genotyping procedure, marker segregation was analysed for 170 of the up to 270 phenotyped individuals. We identified seven linkage groups with an average length of 60 cM, corresponding to seven rose chromosomes in the haploid set. Using an LOD significance threshold of 3.9 we detected a total of 28 QTLs for the nine powdery mildew disease scores under analysis. Using the data from artificial inoculations with powdery mildew race 9, three resistance QTLs explaining about 84% of the variability were mapped. Twelve and 15 QTLs were detected for resistance to naturally occurring infections in the greenhouse and in the field, respectively, over several years.
Subject(s)
Plant Diseases/genetics , Quantitative Trait Loci , Rosa/genetics , Ascomycota/physiology , Chromosome Mapping , Genetic Markers , Genotype , Immunity, Innate/genetics , Lod Score , Plant Diseases/microbiology , Polymorphism, Genetic , Rosa/microbiologyABSTRACT
BACKGROUND: There are various surgical procedures for the treatment of congenital ("true") Brown's syndrome. We have evaluated the effects of a superior oblique tendon recession. PATIENTS AND METHODS: In a retrospective study, we evaluated the files of 22 patients who received surgery for congenital Brown's syndrome in our department. A recession of the superior oblique tendon was performed, when there was a hypotropia in primary position with an abnormal head posture and a significant elevation deficit in adduction, and when these findings did not improve spontaneously. The squint angles (alternate prism and cover test), the monocular motility and the abnormal head posture at distance fixation were assessed. The measurements were performed 1 day before and 3 months after surgery. Thirteen patients were examined 2 - 10 years after surgery. RESULTS: At the time of surgery, the patients were 4 - 17 years old (median 7 years), 13 were male, in 15 patients, the right eye was concerned. Eight patients had an additional esotropia, one patient was exotropic. The vertical deviation in straight gaze was 0 - 12 deg (median 7 deg). The elevation of the eye was restricted to - 10 deg (below horizontal) to 15 deg (median 0 deg) in adduction and to 10 - 35 deg (median 25 deg) in abduction. Sixteen patients had an abnormal head posture. The superior oblique tendon was recessed by 10 mm, in some patients with an additional loop (6x0 polyester). Nine patients received simultaneous surgery for their eso/exotropia. At the end of the operation, the elevation of the eye in adduction (forced duction test) was free. Three months postoperatively, the vertical deviation was 0 - 6 deg (median 1 deg). Twelve patients did not show any abnormal head posture. Inspite of free passive motility, the monocular elevation in adduction was only slightly improved to - 5 to 15 deg (median 5 deg). At the late control, the hypotropia (0 - 4 deg, median 0 deg) and the elevation in adduction (5 - 35 deg, median 15 deg) were significantly improved. CONCLUSION: The recession of the superior oblique tendon is an effective and safe surgical procedure for congenital Brown's syndrome. The efficiency of the procedure is individually variable. Presumably, this variability was caused by the heterogenous etiology of Brown's syndrome rather than by surgical technique. The hypotropia and the abnormal head posture were reduced immediately after surgery, while the delayed improvement of active elevation in adduction often remained incomplete. Postoperative forced upgaze training may be beneficial.
Subject(s)
Ocular Motility Disorders/congenital , Adolescent , Child , Child, Preschool , Diagnosis, Differential , Female , Humans , Male , Ocular Motility Disorders/diagnosis , Oculomotor Muscles/abnormalities , Postoperative Complications/etiology , Strabismus/congenital , Strabismus/diagnosis , Tendons/surgery , Treatment OutcomeABSTRACT
BACKGROUND: The head-tilt phenomenon (difference between the vertical deviations with an ipsilateral and contralateral head-tilt by 45 deg. each) occurring in patients with a superior oblique palsy has traditionally been explained by the lacking contraction of the superior oblique muscle within the synkinetic movement of ocular counterrolling. However, using a computer model, Robinson showed that the superior oblique palsy itself causes only a relatively small head-tilt phenomenon. Adaptive mechanisms amplifying the otolith reflex were suggested to explain the increase of the head-tilt phenomenon in the course of time. In order to reduce the abnormal head posture required for binocular vision, the otolith reflex would be amplified, accepting the greater vertical deviation when the head is tilted to the paretic side . QUESTION: If the head-tilt phenomenon were solely caused by the lacking contraction of the superior oblique muscle, it should be greater in bilateral than in unilateral superior oblique palsies. If an adaptive mechanism were acting to reduce the abnormal head posture, the head-tilt phenomenon should not be greater, and could even be smaller in bilateral than in unilateral superior oblique palsy, because in bilateral (symmetric) trochlear nerve palsies the vertical deviation at straight gaze is already small or absent without adaptation. PATIENTS AND METHODS: We have carried out a retrospective comparison of 10 patients with bilateral symmetric superior oblique palsies and 10 patients with unilateral superior oblique palsy. In all cases, the palsy was acquired and had been present for at least 1 year. RESULTS: The patients with bilateral superior oblique palsy had a head-tilt phenomenon ranging from 0 to 7 degrees (median, 2 deg.). The patients with unilateral superior oblique palsy had a head-tilt phenomenon between 2 and 13 degrees (median, 8 deg.). The difference was significant (p = 0.0117). CONCLUSIONS: The head-tilt phenomenon is smaller in long-standing bilateral symmetric superior oblique palsies than in long-standing unilateral superior oblique palsy. This finding supports the hypothesis that in unilateral superior oblique palsy, an adaptive mechanism augments the head-tilt phenomenon by an amplification of the otolith reflex. However, we presume that the amplification of the otolith reflex is only a side effect of the adaptive change of the vertical fusional vergence tonus and thus the price of the improved vertical fusion, rather than a compensatory mechanism.
Subject(s)
Diagnostic Techniques, Ophthalmological , Exotropia/etiology , Exotropia/physiopathology , Eye Movements , Oculomotor Muscles/physiopathology , Reflex, Vestibulo-Ocular , Trochlear Nerve Diseases/complications , Trochlear Nerve Diseases/physiopathology , Adaptation, Physiological , Adult , Aged , Exotropia/diagnosis , Female , Head Movements , Head-Down Tilt , Humans , Male , Middle Aged , Trochlear Nerve Diseases/diagnosisSubject(s)
Mammary Glands, Animal/growth & development , Proteins/physiology , Animals , Apoptosis , Cell Proliferation , DNA-Binding Proteins/metabolism , Extracellular Signal-Regulated MAP Kinases/metabolism , Female , Gene Expression Regulation, Developmental/genetics , Inhibitor of Apoptosis Proteins , Mammary Glands, Animal/metabolism , Mice , Mice, Inbred C57BL , Mice, Knockout , Milk Proteins/biosynthesis , Milk Proteins/metabolism , NF-kappa B/metabolism , Phosphorylation , Pregnancy , Proteins/genetics , STAT5 Transcription Factor , Time Factors , Trans-Activators/metabolism , X-Linked Inhibitor of Apoptosis ProteinABSTRACT
The medical history, in combination with the physical examination and a 12-lead electrocardiogram, plays a key role in the diagnosis and risk stratification of patients with syncope. However, diagnostic clinical criteria are not uniformly applied. In older studies, the diagnostic criteria for vasovagal or reflex syncope often included typical precipitating events and warning symptoms. More recent studies have documented that a variety of unrecognized stressors can trigger reflex syncope and that warning signs and symptoms may be minimal. A characteristic medical history (a trigger and/or prodromi) is enough to diagnose reflex syncope if the risk for a cardiac cause of syncope is low (e. g. patients < 65 yrs, without a history of heart disease and no ECG abnormalities). In elderly subjects with a higher risk of cardiac syncope, the yield of the medical history is lower. However, a prospective study of the value of the medical history for the diagnosis of syncope with long-term follow-up has not been performed.