PubMed HealthSearch

Biomedical subjects

G Bartl

Publications and source records attributed to G Bartl.

At least 19 recordsLinked to original sources

Different mechanisms underly shifting set on external and internal cues in Parkinson's disease.

A set shifting task consisting of the comparison of two digits according to their numerical value or their form guided by an explicit (external cue) or implicit (internal cue) rule was performed by 8 untreated and 19 treated patients suffering from Parkinson's disease (PD) and 15 control subjects. The subjects could not predict the number of trials for a given target. The treated PD patient group exhibited increased post-shift error rates under the internal cue condition. In the external cue condition, only the untreated patients produced more errors when shifting to a new response criterion. Reaction times were prolonged in treated PD patients, irrespective of type of cue. Large interindividual variability within the patient groups is considered as meaningful and indicates individual differences in the neuropsychological impairment and/or the neurotransmission deficit. Pathophysiological and neuropsychological impairments underlying these findings are discussed on the basis of the models of Penney and Young (1983/1986) and Norman and Shallice (1980/1986).

Aged

[Chandler syndrome--a case report].

Chandler's syndrome is a particularly rare form of unilateral secondary glaucoma, in which--besides other symptoms--corneal epithelial edema occurs even when intraocular pressure rises slightly to above 20 mmHg. For 3 years now the authors have had a patient under observation whose condition corresponds to Chandler's syndrome. A remarkable feature of this case is that corneal edema occurred at physiological pressure levels. The symptoms and course are described; a brief differential diagnostic review is given and therapeutic possibilities are pointed out.

Adult

[Assessment of lesions in various sections of the visual pathway].

The suitability of ultrasonography, computer tomography and Octopus perimetry is illustrated with reference to an investigation carried out in 60 patients. First, the characteristic symptoms are described, depending on the localization of the lesion in the visual pathway. Then the advantages and disadvantages of the various examination methods are compared. In the orbita, echography is the most accurate method in the anterior segments, while the balance shifts increasingly in favor of CT toward the retrobulbar region. As far as intracranial tumors are concerned, there is good correlation between CT and VF findings in the case of sellar processes and pathologic changes of the midline and occipital lobe. In the frontotemporal region, on the other hand, VF defects are found in only one-half of the cases, while in the case of vascular lesions there is no apparent correlation between perimetry findings and the size of the lesion demonstrated on the computer tomogram. The importance of the Octopus for early recognition of such lesions is discussed.

Hemianopsia

[Surgical method for the treatment of irreversible angle-closure glaucoma and aphakic glaucoma. Direct ciliary body coagulation with partial cyclodialysis].

Among 16 patients aged from 31 to 86 there were 13 cases of hemorrhagic glaucoma, three cases of secondary glaucoma from iritis and one case of secondary angle-closure glaucoma after trauma. Reduction in intraocular pressure was achieved by a surgical method which primarily aims to improve the outflow of aqueous humor. The ciliary body is laid bare by preparation of a scleral flap, a partial cyclodialysis is attached on both sides and the ciliary body is induced to stricture by coagulation, so that a large enough cleft is created. Before the operation, pressure ranged from 34 to 64 mm Hg; after the operation, during postoperative periods of observation lasting from two to 32 months, there were 14 cases in which the pressure was below 25 mm Hg and two cases with 30-40 mm Hg respectively. In view of the good results and the few complications, this method of operation can be recommended for treatment of both irreversible angle-closure glaucoma and aphakic glaucoma.

Adult

[A follow-up study of combined cataract/trabeculectomy operation].

In the past 12 years 69 combined trabeculectomy/cataract operations have been performed at Graz University Eye Clinic. Of these, 33 were examined after an average interval of three years. In 23 cases intraocular pressure was regulated without therapy, and four eyes were regulated with additional therapy. In five eyes no satisfactory pressure could be reached and one eye was lost due to late infection. In ten cases a hyphema appeared; in seven cases registered a rise in intraocular pressure was recorded and in two cases a flat chamber. In view of the great variety of indications this method seems to be especially suitable for elderly patients.

Aged

[A case of papillophlebitis].

A case history of a young man with recurrent papillophlebitis. The fluorescein angiogram showed an extensive hyperfluorescence of the disk and surrounding retinal veins in the venous and late phase. The electro-ophthalmological findings were normal in both eyes, while computerized perimetry demonstrated an enlarged blind spot in the bad eye but was normal in the other. The paper concludes with a description of the differential diagnosis of papillophlebitis, papillitis and papilledema caused by vascular occlusive disease or increased intracranial pressure.

Diagnosis, Differential

[Light and electron microscopy results following photocoagulation of ciliary processes with argon lasers].

The authors' own clinical observations have shown that a pressure-lowering effect in secondary glaucomas resistant to therapy can be obtained by photocoagulation of the pars plicata of the ciliary body using an argon laser. In order to be able to estimate the damaging effect of photocoagulation and thus to be able to administer it in a sensible dose, the authors applied this technique to four patients with tumorous eyes that had to be enucleated, with a subsequent histological and electron-microscopical scrutiny. The laser energy was varied from 750 to 2000 mW at a constant exposure time of 0.2 s and a dot size of 100 micrograms. With clear-refracting media an energy of 1000 mW brought about coagulative effects without any substantial side-effects. Damage was then generally restricted to the aqueous humorproducing formation, i.e., the ciliary epithelium and the adjacent stromal part.

Ciliary Body

The effects of visual field changes and ocular hypertension on the visual evoked potential.

The effects of visual field changes and ocular hypertension on visual evoked potentials were investigated by photopic ERG and by luminance and pattern-reversal EPs on 116 glaucomatous and on 7 normal eyes. The problem was approached by way of four investigations: Firstly, which nerve structures are affected by glaucoma and how do visual field defects caused by glaucoma influence the EP? The results show a functional diminution of all intraocular nerve structures in which the prelaminary part of the optic nerve is most affected. The EPs, especially the pattern-reversal EPs, are markedly diminished if the visual field defects extend inside the 10 degree boundary. Differences in the visual field defects of both eyes and the course of the sickness can be well observed by the EPs. Secondly, which preoperative prognosis for visual acuity produced by the EP can be given to patients who have a dense cataract in addition to glaucoma? A postoperative improvement of the visual acuity can be expected if the L-EPs are within the standard deviation. If the EP is distinctly diminished and does not increase with increasing stimulus intensity, then there is no hope for an improvement of the visual acuity after the operation. Thirdly, does a decrease of intraocular pressure in chronic and acute glaucoma influence the EP? In acute glaucoma with pressure levels of 50 mmHg or more, and sometimes in chronic glaucoma with pressure levels of about 30 mmHg, an increase of the amplitude of the EP and an improvement of the visual field could be noticed after pressure regulation. Fourthly, what is the behaviour of the EP in normal and glaucomatous eyes at experimentally elevated intraocular pressure? The amplitudes of the ERG components show a gradual decrease in normal as well as in glaucomatous eyes when intraocular pressure is increased and are maintained when intraocular pressure reaches systolic ophthalmic blood pressure. On the other hand, the EPs show a strong decrease in amplitude when intraocular pressure exceeds the mean ophthalmic blood pressure, particularly in the case of glaucomatous eyes.

Evoked Potentials, Visual

[Diagnosis of space-occupying renal processes: sonography and aimed fine-needle biopsy].

It is reported on 3 cases in which by sonographic examination a tumorous process could be established. In all cases the additional investigation by fine needle biopsy and cytological examination proved the presence of malignant cells. This local renal process proved by sonography could be verified neither by i.v. pyelographic nor arteriographic methods. For two patients the diagnosis based on sonography, fine needle puncture and cytological test could be verified by operation. The third patient was not operated in spite of malignant cells in the cytogram because of negative computer tomography provided by an external hospital.

Aged

[Oncocytoma of the thyroid gland].

The Huerthle cell tumor is quite frequent in southern Germany; this is shown by examinations of patients from our field hospital for nuclear medicine. Our findings conclude with data presented by Galvan (Salzburg). The certainly quite short observation period shows that Huerthle cell adenomas occur much more frequent than carcinomas, when a Huerthle cell neoplasm is diagnosed cytologically. Our investigations show, that Huerthle cell tumors of the thyroid gland are a not wellknown and rare disease, which necessitates a clear decision as result of the cytological finding as far as necessary surgical measures are concerned. This is probably the only way to improve the efficiency of measures for early diagnosis and treatment of tumors of the thyroid gland. Considering the want of clearness which still exists referring to the dignity of Huerthle cell tumors in our opinion even cases which had been diagnosed as adenomas histologically should be controlled regularly once a year during an observation period of ten years.

Adenoma

[A case of unilateral retinitis pigmentosa].

A case of unilateral retinitis pigmentosa observed over a period of 15 years is reported. The affected eye showed all typical pathologic manifestations, while in the healthy eye all findings--including ERG and EOG-- were normal. In spite of the unequivocal ophthalmological diagnosis the condition should be regarded as a tapetoretinal degeneration with the clinical picture of unilateral retinitis pigmentosa so long as there is no evidence that it is hereditary.

Adult

[Clinical experience with different methods of treating herpes corneae (author's transl)].

The modes of action of IDU and TFT were compared in tests employing them both as a monotherapy and in combination with iodine debridement in 60 patients suffering from superficial herpetic keratitis. The combination therapy was used for patients showing only dendritic stains in the corneal epithelium, while the monotherapy was used for patients who had additional lesions in the region of Bowman's membrane. Both with the monotherapies and the combination therapies the average duration of healing was shorter with TFT.

Debridement