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Biomedical subjects

U Havelius

Publications and source records attributed to U Havelius.

17 recordsLinked to original sources
PubMed2001

A Horner-like syndrome and cluster headache. What comes first?

PURPOSE: To evaluate if an ocular sympathetic lesion may be a prerequisite for cluster headache to occur. METHODS: Patients with a permanent Horner-like syndrome at the debut of cluster headache were identified from history and photographs. RESULTS: Among 57 patients with cluster headache, seven patients (5 males and 2 females) exhibited a permanent Horner-like syndrome on the painful side when first seen at the outpatient department. During this study it was possible to get information from six of these patients and five of them had side constant cluster headache. In retrospect, these five patients had had a Horner-like syndrome for years prior to the onset of ipsilateral cluster headache. CONCLUSION: The findings indicate that a sympathetic lesion or dysfunction may be a prerequisite for the subsequent development of cluster headache.

Adolescent↗
PubMed2000

Impaired dark adaptation in polycythemia. Improvement after treatment.

PURPOSE: To determine if dark adaptation is reduced in individuals with polycythemia and if so whether there is any improvement in dark adaptation after treatment. METHODS: Dark adaptation was recorded monocularly by automatic dark adaptometry in ten consecutive patients with polycythemia before and after treatment. Analogue investigations were performed in 31 healthy control subjects. RESULTS: Dark adaptation was markedly impaired in the patients as compared with the control subjects. After reduction of the red cell count and normalization of the hematocrit and hemoglobin the dark adaptation was markedly improved. There was no significant change in dark vision in the control subjects negating a confounding learning effect. CONCLUSION: The findings indicate a sustained but reversible neuronal hypofunction secondary to polycythemia. As the rheological abnormality was normalized, dark adaptation was improved, probably secondary to normalized microcirculation within the retina or the brain, or both, possibly with reactivation of formerly inactive neuronal cells.

Adult↗
PubMed1999

Human ocular vasodynamic changes in light and darkness.

PURPOSE: To determine whether changes in the retinal blood flow in light and darkness occur in humans. METHODS; The systolic and diastolic flow velocities were measured by color Doppler in the ophthalmic and the central retinal arteries in 12 healthy individuals in light and darkness. RESULTS: In the ophthalmic artery there was a trend toward lower systolic velocity in darkness compared with that in the light, but there was no change in diastolic velocity. In the central retinal artery the systolic and the diastolic flow velocities were markedly increased in darkness. After re-exposure to light the systolic flow velocity decreased. CONCLUSIONS: Darkness is associated with increased blood flow velocity in the central retinal artery, probably reflecting increased retinal metabolic demands by the photoreceptors.

Adult↗
PubMed1998

A computerised adaptometer.

PURPOSE: The design of an automatic instrument for the estimation of subjective dark adaptation (minimum perceptible for light) by an uninterrupted chain of trials. METHODS: A light emitting diode is used as test light. The patient answers by pressing a button when light is perceived. The process is controlled by means of a lap top computer and traces the adaptation course step by step. RESULTS: The instrument was tested by recording the course of dark adaptation (DA) in a clinical series of normals and of patients. The threshold sensitivity (after 25 min in darkness) showed very satisfying reproducibility. CONCLUSION: The instrument described was found to be reliable and well suited for clinical routine as well as experimental work.

Aged↗
PubMed1998

Pterygium with granuloma faciale-like histologic picture.

PURPOSE: Description of a case with an atypical conjunctival pterygium with an unusual histologic picture suggesting granuloma faciale, a vasculitis-like disease of facial skin with a chronic, indolent course. Discussion of diagnosis and treatment. METHODS: Repeated clinical and histologic observations. RESULTS: A pterygium with an unusual nasosuperior localization was excised and examined microscopically. There was a dense vessel-related inflammatory infiltrate, essentially identical to granuloma faciale. The lesion recurred and, as granuloma faciale is amenable to dapsone (diphenyl sulfone), treatment with 100 mg daily resulted in rapid improvement, whereas reduction of the dose to 50 mg daily resulted in relapse. Reinstitution of the original dose resulted in normalization of the histologic picture. However, a recurrent pterygium developed, which had a quite unspecific histologic picture. CONCLUSION: A disease with a histologic picture essentially identical to granuloma faciale may manifest itself as a pterygium. Treatment with dapsone may be beneficial.

Aged↗
PubMed1997

The enhanced ciliospinal reflex in asymptomatic patients with cluster headache is due to preganglionic sympathetic mechanisms.

An amplified ciliospinal reflex response has been documented in patients with cluster headache, lacking a Horner-like syndrome. The mechanism is unknown. Tentatively, it may be due to an increased release of monoamines from post-ganglionic sympathetic nerve endings or an increased density of postsynaptic adrenergic receptors in the dilatator muscle of the iris. The instillation of a 1% phenylephrine solution into the conjunctival sac induces mydriasis by stimulating postsynaptic adrenergic receptors in the dilatator muscle of the iris, while the instillation of a 2% tyramine solution causes mydriasis by releasing noradrenaline from the presynaptic sympathetic nerve terminals in the iris. According to these premises, a positive correlation should be expected between the ciliospinal reflex response and the pupillary response to tyramine, if the enhanced ciliospinal reflex response was due to an increased presynaptic release of monoamines. No such correlation was found. Nor was there any positive correlation between the ciliospinal reflex response and the pupillary response to phenylephrine, contradicting an increased density of postsynaptic monoaminergic receptors in the dilatator muscle of the iris as the explanation. However, there was a significant positive correlation between the pupillary responses to phenylephrine and tyramine, ruling out any functionally caused "denervation" hypersensitivity in the dilatator muscle of the iris. It is concluded that the amplified ciliospinal reflex response in cluster headache patients (lacking a Horner-like syndrome) reflects compensatory pathophysiological mechanisms proximal to the third-order sympathetic neuron.

Adult↗
PubMed1997

I. Impaired dark adaptation in symptomatic carotid artery disease.

It has been known for more than a century that even slight hypoxemia reduces dark adaptation. We studied dark adaptation in symptomatic carotid artery disease. Twenty-one consecutive patients scheduled for first-time carotid endarterectomy and 31 age-matched control subjects with normal carotid arteries were examined by dark adaptometry monocularly and were tested repeatedly on consecutive days. The average degree of internal carotid stenosis on the symptomatic side was much greater than that on the contralateral side. Dark adaptation was markedly impaired in the patients as compared with the control subjects. In the patients there was no difference in dark adaptation between the symptomatic and nonsymptomatic sides. The existence of carotid stenosis correlated to the level of dark adaptation. Pupillary size and age correlated to the dark adaptational level but did not affect the effect of carotid stenosis on dark adaptation. The decreased dark adaptation may be due to insufficient blood supply or repeated subclinical microembolization to the retinae, the brain, or both.

Aged↗
PubMed1997

II. Improved dark adaptation after carotid endarterectomy. Evidence of a long-term ischemic penumbra?

We have reported that dark vision is impaired in symptomatic carotid artery disease and that the impairment correlates with internal carotid artery stenosis. To find out whether this impairment is reversible after carotid endarterectomy, dark adaptation was examined pre- and postoperatively. Twenty-one consecutive patients were examined by dark adaptometry. Two examinations were done for each eye on two consecutive days pre- and postoperatively. Thirty-one matched control subjects were examined under identical conditions. The control subjects did not have clinical evidence of carotid artery disease. Patients and control subjects were free of ophthalmologic disorders. Dark vision frequently improved remarkably after endarterectomy. The average retinal sensitivity to light in darkness on the operated side doubled, and there was also improvement on the nonoperated side. There was no significant change in dark vision in the control subjects, negating a learning effect. The findings suggest the existence of reversible neuronal ischemia secondary to hemodynamic causes or frequent subclinical microembolization. Because the circulatory conditions are optimized, formerly inactive, surviving neurons may regain function.

Aged↗
PubMed1996

Clusterlike headache in a patient with a pituitary adenoma. With a review of the literature.

A man had left-sided atypical clusterlike headache for 9 years before he developed symptoms and signs consistent with acromegaly. Preoperative evaluation revealed raised levels of somatomedin C and growth hormone. An MR indicated a left-sided intrasellar mass measuring 8 x 7.5 x 10 mm. He underwent surgery and microscopy confirmed the diagnosis of a benign hypophyseal adenoma. Postoperatively, the acromegalic features regressed, and for the last 4 years the patient has been completely free from headache attacks. On pharmacological testing of the pupillary response to 1% and 5% phenylephrine and 2% tyramine solutions, there was no convincing evidence of persistent sympathetic dysfunction on the earlier symptomatic side.

Adenoma↗
PubMed1996

Ciliospinal reflex response in cluster headache.

The ciliospinal reflex response is mainly mediated by second- and third-order sympathetic nerves to the dilatator muscle of the iris. As the pupillary response to various pharmacological agents indicates a sympathetic dysfunction in patients with cluster headache, the ciliospinal reflex was studied in 25 patients. Five of these patients with cluster headache exhibited a Horner-like syndrome (miosis, ptosis) on the symptomatic side. The pupillary responses to phenylephrine and tyramine showed that the Horner-like syndrome was due to postganglionic sympathetic nerve dysfunction. Their ciliospinal reflex response on the symptomatic side was significantly less than in controls and in other patients with cluster headache, lacking a Horner-like syndrome. This also applied to the nonsymptomatic side compared to the majority of cluster headache patients without any clinical evidence of sympathetic nerve dysfunction. These findings seem to delineate those patients with a Horner-like syndrome as a subgroup, distinctly separated from the majority of cluster headache patients. Furthermore, the findings indicate that the Horner-like syndrome is not a consequence of repeated attacks of headache over many years, but is a manifestation of bilateral cephalic sympathetic dysfunction being more marked on the symptomatic side. In 18 (72%) of our 25 patients, an asymmetric and lower ciliospinal reflex response on the symptomatic side was seen. In 3 (12%) patients, there was no difference in the response. In 4 patients (16%), the incorrect side was indicated by an asymmetric reflex response. Two of these patients (8%) had suffered from cluster headache on alternating sides. In summary, the findings support the concept that dysfunction of the sympathetic nervous system, whether peripheral or central is involved in the pathophysiology of cluster headache.

Adult↗
PubMed1996

The pupillary response to tropicamide in Alzheimer's disease.

An increased pupillary response to a weak solution of tropicamide has recently been suggested to be diagnostic for Alzheimer's disease. If so, it would have far-reaching implications. We performed a masked study involving 17 patients with Alzheimer's disease and 20 mentally healthy controls with respect to the pupillary response induced by tropicamide. We found no significant difference in pupillary dilatation between patients and controls (19.7 +/- 11% versus 19.1 +/- 9%; p = 0.19).

Aged↗
PubMed1995

An instrument for recording the ocular pulse wave.

An instrument for recording the ocular pressure pulse is described. Examples of recordings showing individual differences in the shape of the pulse curve are demonstrated. The properties of the instrument as to the frequency response in the range 0.5-10 Hz are established with the aim of correcting the recordings for instrumental errors.

Aged↗
PubMed1994

Recurrence of cluster headache after carotid thrombendarterectomy.

The pathophysiology of cluster headache is largely unknown. One important contributing factor may be an abnormal intracranial-extracranial hemodynamic state. A male patient suffered from chronic left-sided cluster headache for about 15 years. After the institution of lithium therapy the symptoms abated. He was completely free from cluster headache for more than 20 years, until the first postoperative day after a thrombo-endarterectomy for symptomatic 70% carotid stenosis. This case report indicates the importance of abrupt carotid hemodynamic changes along with dysfunction of the cephalic sympathetic nervous system in the initiation of cluster headache.

Angiography↗
PubMed1983

Reversibility of neurological deficits in vitamin B12 deficiency.

A female patient with subacute neurological deficits secondary to an hereditary vitamin B12 deficiency was repeatedly examined clinically and neurophysiologically. It is concluded that neurological normalization after treatment with vitamin B12 also occurs within the CNS. Such normalization takes place soon after initiating treatment and probably reflects other neuronal mechanisms that remyelination, i.e. recovery from conduction block in fast somatosensory pathways and/or improvement of synaptic transmission.

Evoked Potentials, Somatosensory↗
PubMed1982

Carotid fibromuscular dysplasia and paresis of lower cranial nerves (Collect-Sicard syndrome). Case report.

A patient suffered the acute onset of unilateral pareses of the ninth through 12th cranial nerves (Collet-Sicard syndrome). Ipsilateral retrograde jugular phlebography and carotid angiography revealed irregular aneurysmal changes of the internal carotid artery at the base of the skull, causing compression of the internal jugular vein below the jugular foramen. This finding is discussed in relation to the clinical symptoms and signs, and possible mechanisms are examined. Family history as well as the clinical and roentgenological findings were compatible with a diagnosis of fibromuscular dysplasia.

Adult↗
PubMedDate not supplied

Cluster headache in two sisters. Pupillary response to phenylephrine and tyramine.

Two sisters with cluster headache were studied with respect to the pupillary responses to instillation into the conjunctival sac of a single drop of a 1% solution of phenylephrine and a 2% solution of tyramine. The changes in pupillary diameters were documented by photographic pupillometry prior to and at 15, 30, 60, and 90 minutes after the instillations. Of the two sisters, one (case A) was examined during a symptom-free interval, when she had been free from cluster headache attacks for 2 1/2 years. When the cluster headaches recurred, retesting was performed. The other sister (case B) had been free from cluster headaches for 9 years, when she was examined. The findings indicate hypofunction within the postganglionic sympathetic nerve fibers during a cluster headache period. The hypofunction is bilateral, and thus, can not be a consequence of the unilateral cluster headache attacks. During remissions, tyramine induces a marked mydriasis, particularly on the symptomatic side, tentatively indicating an excessive release of stored monoamines.

Adult↗