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Biomedical subjects

T Palva

Publications and source records attributed to T Palva.

At least 19 recordsLinked to original sources
PubMed1979

The meatally based musculoperiosteal flap in cavity obliteration.

A meatally based musculoperiosteal flap that was formed for radical mastoid cavity obliteration was deliberately excised during revision surgery in three cases of recurring tympanic cholesteatoma. The flaps, which contained subcutaneous connective tissue, were well vascularized and contained large, viable muscle bundles and many nerve trunks from the postauricular branch of the facial nerve. In two cases, the periosteum-attached bone chips that had been removed from the patient's mastoid tip region and implanted to form a new bony canal wall were viable and gave the intended support for the meatus after radical ear surgery.

Adolescent↗
PubMed1979

Vestibular sensory epithelium in Meniere's disease.

Utricle and horizontal semicircular canal ampulla removed during labyrinthectomy from 11 patients with advanced Meniere's disease were studied under light and electron microscope. In light microscopy the epithelium of both sensory areas appeared fairly normal. Many sensory cells revealed fluid-filled crescents at the nucleus and many cells were extensively vacuolated. Ultrastructurally, a part of the observations were apparently artifacts due to specimen handling; some were normal, age-related findings. Some changes were considered secondary to dilation of the endolymphatic space. True signs of degeneration, seldom seen in these specimens were intraepithelial cysts, necrotic cells, and dark homogeneous masses in the sensory epithelium and dilated nerve fibers in the subepithelial tissue. No general degeneration of the utricular macula or ampullar crista seems to occur in Meniere's disease.

Adult↗
PubMed1979

Adrenergic innervation of blood vessels. A fluorescence microscopic study of the eighth nerve and inner ear structures in man.

Fluorescence microscopy was used to examine the perivascular adrenergic innervation in the eighth nerve and vestibular end-organ specimens from 13 patients with otoneurological diseases. It was observed that all the blood vessels accompanying the cochlear and vestibular nerves from patients with acoustic neuroma or Meniere's disease were devoid of specifically fluorescent fibers, while several adrenergic fibers were seen around the arterioles accompanying the inferior vestibular nerve from the patient with sudden deafness.

Adrenergic Fibers↗
PubMed1979

Adrenergic innervation of the eighth nerve and vestibular end organs in man.

Fluorescence microscopy was used to examine the adrenergic, blood-vessel-independent innervation of the 8th nerve and inner ear specimens in patients with otoneurological diseases. Specifically fluorescent adrenergic axons were scantily seen among the myelinated nerve fibers in the 8th nerve and in the subepithelial regions of the end organs but not in the endolymphatic sac.

Adrenergic Fibers↗
PubMed1979

Menière's disease: morphological findings in eighth nerve and vestibular end organs.

37 patients with advanced Menière's disease were operated on by translabyrinthine 8th nerve neurectomy or middle fossa vestibular neurectomy. Cochlear and vestibular nerves, epithelia of the utricular macula and ampullar crista of horizontal canal were studied. All specimens were fairly well preserved and the microscopic studies suggested that there is no general deterioration of these structures even in long-standing, advanced Menière's disease, but some minor deviations from normal are present in individual cells.

Adult↗
PubMed1979

Functional and histological findings in acoustic neuroma.

27 patients with acoustic neuroma were operated on by translabyrinthine tumor removal. At operation 8th nerve compartments were identified and removed for study. Results of the audiological test battery and vestibular tests were compared with histological state of the nerve specimens studied. The tumor appears only seldom to invade the cochlear nerve in cases with 'cochlear' hearing loss, but in the majority of cases with 'retrocochlear' hearing loss the cochlear nerve is invaded.

Cochlear Nerve↗
PubMed1979

Recent expericience in the surgery of acoustic neurinomas.

A translabyrinthine method was used in 49 and a suboccipital approach in 55 cases, for the removal of an acoustic neuroma. The translabyrinthine procedure is well suited in cases with no pontine compression, whereas in large tumours the wide opening in the suboccipital method gives added safety to the procedure. The mortality rate was 3% and the facial nerve function after translabyrinthie surgery showed permanent paralysis in 4 patients. A team approach using the suboccipital route has been started in an attempt to save hearing in small- and medium-sized tumours.

Ear, Inner↗
PubMed1979

Vestibular neurectomy.

Vestibular neurectomy technique used for the standard middle fossa approach and for a total translabyrithine VIII nerve section is described. The middle fossa approach has been used in 49 cases of mainly Meniere's disease and basically the same approach for nerve decompression has been used in 19 cases of facial paralysis, 15 being due to Bell's palsy, 2 to petrous pyramid cholesteatoma and 2 to facial nerve Schwannoma. In unilateral Meniere's disease with no further function in hearing, vestibular neurectomy gives good results in alleviating vertigo.

Cholesteatoma↗
PubMed1979

Mastoid obliteration.

Mastoid obliteration is recommended as a routine procedure in all mastoid surgery. Bone chips from the mastoid tip, bone paté from the cortical bone and lyophilized dura can all be employed effectively to fill the epitympanic space and Traumann's triangle. The former annulus is reconstructed using lyodura and periost-bearing bone and the canal wall is fortified and the cavity filled with the metally based postauricular musculoperiosteal flap. Any remaining cavity is filled with bone chips and bone paté.

Bone Transplantation↗
PubMed1979

Vestibular neurectomy and saccus decompression surgery in Meniere's disease.

Results of vestibular neurectomy, total eighth nerve section, and saccus decompression in 42 patients with Meniere's disease are reported. Vestibular nerve section was found in isolated cases to be a very effective method of abolishing the symptom of vertigo. Hearing is not affected but may be lost owing to opening of the vertical canal or disruption of blood supply. Saccus surgery might be the surgical treatment of choice in early cases with good hearing but in patients with fixed non-fluctuating hearing loss, rehabilitation can be effected only by vestibular neurectomy. In bilateral cases either sac surgery or the use of vestibulotoxic drugs is advised.

Adult↗
PubMed1978

Ultrastructural features of spiral ganglion cells. A study of patients with hearing loss of varying origins.

Fresh specimens of the acoustic nerve that were obtained during vestibular neurectomy or acoustic neuroma removal were studied for structure of the spiral ganglion cells. These were large, round or oval cells with many cytoplasmic organelles and were surrounded by Schwann cells. Schwann cells formed a single layer or perikaryal sheath and the cells were thus unmyelinated. In one case the specimen contained part of the spiral ganglion, but in six others spiral ganglion cells were found outside of Rosenthal's canal, among the myelinated nerve fibers. In three cases the ear was deaf due to cochlear insult, but the nerve fibers and ganglion cells showed no retrograde degeneration. The neurophysiologic features of the cochlear nerve should be considered because unmyelinated ganglion cells may have a different conduction capacity in comparison with thickly myelinated cells.

Adult↗
PubMed1978

Pathologic features of the cochlear nerve in profound deafness.

Cochlear nerves transected in the internal meatus were studied in six totally deaf ears and in one ear with profound deafness. In five ears deafness had followed surgical procedures in the oval window, in one it was the result of a mumps infection, and one was probably due to a virus infection or a vascular lesion. In four cases there was no great reduction in the nerve fiber population and the ultrastructure appeared normal. In three nerves there was a reduction in the number of nerve fibers, interfibrillar fibrosis, and disorganized material or extensive degenerative changes in the myelin sheaths. In all specimens artificial myelin changes were seen that apparently resulted from manipulation of the specimens at removal. Analysis of these cochlear nerves suggests that retrograde degeneration after severe cochlear insults may not be as frequent as has been thought on the basis of animal studies.

Adult↗
PubMed1978

Eighth nerve in acoustic neuromas. Special reference to superior vestibular nerve function and histopathology.

Eighth nerve specimens were removed during acoustic neuroma surgery, and findings were related to cochlear and especially to superior vestibular nerve function as studied by conventional caloric testing in 21 cases. The origin of the tumor was in eight cases the inferior and in two cases the superior vestibular nerve, and in eight cases the vestibular nerve without more specific localization. In three advanced cases the exact site of origin could not be determined. Leaving age-related changes out of account, the utricle and horizontal canal ampulla appeared normal in all ears except one in which the ampulla was replaced by tumor tissue. In 11 ears the superior vestibular nerve was histologically intact and three of these ears also showed normal caloric responses. In seven ears there was a canal paresis, and in three no reaction was obtained. The ten ears with partial or total nerve invasion by tumor either showed a weak reaction or no response at all. It is likely that an early conduction block arises in both cochlear and vestibular nerves, and reduced reactions to appropriate stimuli do not warrant conclusions that the numbers of anatomically intact nerve fibers possibly are reduced.

Adult↗
PubMed1978

Cochlear nerve in neurilemomas. Audiology and histopathology.

Correlative data between the histopathologic changes in the cochlear nerve and audiologic findings are reported in 16 cases of neurilemomas. Poor speech discrimination, positive or absent recruitment, excessive adaptation, or separation of forward vs reverse continuous tone Bekesy tracings did not correlate with the number of preserved nerve fibers. There were several cases with profound hearing loss in which the nerve fiber population approached normal. Histologically, pathologic changes included dilated fibers and increased interfibrillary collagen. In many specimens the fibers were further apart than normally, especially in the immediate vicinity of the tumor, and many lay between tumor cells. The tumor-nerve interface was usually gradual and no abrupt change appeared at the transition from the nerve to the tumor, the Schwann cells appearing to continue as tumor cells. Nonspecific changes apparently due to specimen handling were seen in some areas of most specimens.

Adult↗
PubMed1978

Use of lyophilized dura in aural surgery.

Lyophilized dura was utilized in chronic ear surgery to cover raw promontory surfaces, to stabilize the reconstructed ossicles, to raise the posterior insertion point of the grafted drum after canal wall removal, and to fortify the soft posterior canal wall. In 3 guinea pigs, lyodura was also placed in the bulla and studied 6, 12 and 16 months later. In 6 months of time, lyodura had become covered with normal epithelium and in 12 months of time, the greatest part of the lyodura was resorbed from the middle ear, normal epithelium having developed. In the canal wall area, resorption is slower and collagenic dural network is clearly recognizable even after a period of 24 months. Lyophilized dura contains no irritating material and is considered to be a versatile and useful material in chronic ear surgery.

Animals↗
PubMed1977

The morphology of the vestibular nerve in a patient with normal vestibular function and in patients with Ménière's disease.

The morphology of the vestibular nerve was studied in three fresh nerve specimens obtained by surgery from two patients with Ménière's disease and one patient with tinnitus after an attack of sudden deafness. The number of nerve fibres appeared light microscopically normal. The vestibular ganglion cells of the Ménière-specimens showed, as a characteristic finding advanced vesiculation of the cytoplasm. This change was confirmed by electron microscopy and the vacuoles appeared to consist of widened endoplasmic reticulum cisternae. Numerous primary lysosomes and lipofuscin granules were observed in all vestibular ganglion cells but their number appeared increased in the specimens from Ménière-patients. Some of the vestibular ganglion cells of these patients showed a filamentous appearance and the number of glycogen granules seemed reduced in all of them. All vestibular ganglion cells observed were unmyelinated. The degenerative changes observed might explain the typical elevation of the threshold for vestibular stimulation in Ménière's disease.

Adult↗
PubMed1977

Evaluation of patients with bronchial carcinoma.

Results of diagnostic procedures are presented on 259 successive patients with bronchial cancer at Päivärinne Chest Hospital during the period 1967-73. The most common tumours were epidermoid (56%), 'small cell' (20.5%) and adenocarcinoma (9.5%). In 106 patients (41%) chest radiography suggested a tumour, though bronchoscopy was normal, and in 22 cases (8.5%) the radiograph was normal but bronchoscopy revealed a tumour. In 10 (4%) both the radiological and the bronchoscopic findings were normal. A definite histopathological diagnosis was reached by bronchoscopy in 144 patients (44%), by mediastinoscopy in 14 (5%), by fine needle biopsy in 28 (11%) and operatively in 103 (40%). Using all methods of treatment prognosis was significantly better in the group that had been diagnosed by mass miniature radiography, or accidentally (29% alive) as compared with those who had symptoms of the disease (6%).

Adult↗