Biomedical subjects

T Rahko

Publications and source records attributed to T Rahko.

At least 55 records · Page 3Linked to original sources

PubMed1977

Equilibrial disturbances caused by hearing aids in hard of hearing children.

To 22 hard-of-hearing school pupils a 2 sec. tone pip of 1500 Hz was presented at 120 to 130 dB SPL's (equals 113-123 dB ISO) to both (=44) ears. In 32 of the ears (?) the sound stimulus elicited an ENG change and thus a possible disturbance of equilibrium, 2 cases of type A, 3-10 sec. nystagmus; I case of type B, with continuing nystagmus; 3 cases of type C, with strengthening nystagmus; and I case of type D, with direction-changing nystagmus, were found. We conclude that, in perceptive hearing defects, the maximum output of hearing aids should be limited to 120 dB, not only because of the effect on hearing thresholds. but also on the equilibrial sense. Again we recommend that hearing aids should not be used in those surroundings where loss of equilibrium is dangerous.

Adolescent↗

PubMed1977

The eustachian tube function in secretory otitis media in children: a follow-up study.

Twenty-three patients suffering from secretory otitis media were examined. The mean age of the group was 6 years. Adenoidectomy and insertion of polyethylene tympanostomy tubes was made. The tubal function was studied by measuring the middle ear pressure on the morning after operation and once a month during the following five months by using the air pressure equilibration technique. In 23 ears (79%) the pressure was considered to be normal and in 10 ears (30%) abnormal at the first measurement. After 5 months the corresponding groups were 26 (79%) and 7 (21%).

Adenoidectomy↗

PubMed1977

The effect of loud noise on the vestibular system.

The effect of a 2 sec 113--123 dB ISO pure tone stimulus on ENG was studied. The material consisted of patients with operated and unoperated otosclerosis, normal ears, patients with sensorineural defects, and cases of chronic otitis media. ENG changes were found in 45% of patients with sensorineural hearing loss, in 35% of operated otosclerotics, in 15% of unoperated otosclerotics, in 15% of patients with chronic media, but in none of the normal-hearing patients. Most of the patients showing ENG changes felt dizzy. These results seem to imply a possible risk to patients with sensorineural hearing loss working in high noise levels.

Adult↗

PubMed1976

Experimental regional enteritis in pigs.

Lymphatic obstruction is constantly present in regional enteritis, but its role in the pathogenesis is poorly understood. To clarify this the mesenterial lymphatics of the terminal ileum were obstructed in 21 pigs chosen for experiments because spontaneous ileitis is common in pigs. Long-lasting obstruction was produced by injecting formaline into regional lymph nodes. The growth of the pigs was retarded. Their ileum became reddish and oedematous with numerous intra-abdominal adhesions, and mucosal ulcerations. Eleven pigs developed fistulae; none had chylous ascites. Histologically the subserosa was infiltrated by round and giant cells giving an impression of granulomatous inflammation. Many lymphatics were thrombosed. The lymphoid tissue was hyperplastic. These changes became more prominent with extensive subserosal fibrosis after three weeks, when the oedema diminshed. Transmural inflammation with round cell aggregations was then the most typical feature. Purulent infection with crypt abcesses appeared near the fistulae. If the function of lymphatics is destroyed, transport of particles too big to enter blood vessels is inhibited. This produces chronic irritation and oedema with declining tissue nutrition and oxygenation, thus causing fibrosis. Moreover, the intestinal lumen is a source of infections, and the oedematous tissue is easily infected. This may lead to mucosal ulcerations and, progressively, to fistulae.

Animals↗

PubMed1974