Poznan's program of cochlear and brainstem implantation: a general review.

The cochlear implantation program in Poznan started in January 1994. Within 8 years, 151 patients were implanted (149 cochlear and 2 auditory brain-stem implants). The implanted group comprised 111 children and 40 adults. We have extended the lower age limit for cochlear implant candidates, and the youngest implanted patient was 18-months-old at the time of surgery. We have also implanted six multi-handicapped subjects. All patients were implanted with different nucleus devices (22, 24 M, 24 K, 24 Contour, 24 Double Array and 24 ABI). Insertion of the Nucleus 24 Contour electrode carrier requires a little larger cochleostomy in comparison with conventional straight array. After insertion, the intraoperative measurements are taken (impedance telemetry, electrically evoked stapedius reflex and NRT). The day after surgery, each patient undergoes an X-ray examination (the cochleogram or cochlear view). The calculated length of the electrode array insertion was 12.75-24.0 mm (mean: 22.05 mm) and the degree of electrode rotation was 180-540 degrees (mean: 292.82 degrees). After speech processor switch-on, we performed NRT measurements. Our results indicated that the NRT threshold was in 51.4% of the dynamic range within the group of examined patients. The adults' progress of rehabilitation was checked during individual sessions. The rehabilitation of children included two rehabilitation schedules: continuous ones and weekly rehabilitation camps. The progress of the recovery process of implanted children enabled them to change their school profile from hearing impaired to mainstream. Voice rehabilitation is often monitored by acoustic analysis using the Multi Dimensional Voice Program (MDVP).

[Own experience in supracricoid laryngectomy with GHP and GHEP type of reconstruction due to larynx cancer]. / Wlasne doswiadczenia stosowania laryngektomii nadpierscieniowej z rekonstrukcja typu CHP i CHEP w leczeniu raka krtani.

The results of the surgical treatment of the larynx cancer (glottic-supraglottic) by supracricoid laryngectomy with CHP and CHEP type of reconstruction were presented. Material consists of 160 cases (88 after CHP and 72 after CHEP). 5 years survival rate was obtained in over 71% of cases in all material. Decannulation was possible in 126 (79%) patients. Feeding tube removal before 4 weeks after operation was done in 139 (87%) cases. In subjective assessment all patients had social efficient speech. Favourable results of the treatment encourage wider application of supracricoid laryngectomy.

[Laryngotracheal separation procedure after oncological pharyngeal and laryngeal operations]. / Postepowanie chirurgiczne (rozdzielenie krtani i tchawicy) w przewleklej aspiracji po operacjach onkologicznych gardla i krtani.

Principles of the operative technique and indication for permanent laryngotracheal separation in chronic aspiration after oncological operations are being presented. The operation is done while the tracheostomy is present. It consists of horizontal section of the trachea on the level of the tracheostomy and formation the new one by using the lower of the trachea with the skin. Upper sublaryngeal section of the trachea is being closed by stitches. This operation was performed in our clinic in one patient after partial laryngectomy due to the cancer and in two patients after extended resection of the palatal tonsil, base of the tongue and lateral wall of the hypopharynx. In all the cases the follow up was without major complications.

[Cochlear implantation through the middle fossa approach]. / Implantacja wszczepu slimakowego z dojscia przez srodkowy dól czaszki.

The inner part of cochlear implant is inserted into inner ear during surgery through mastoid and middle ear. It is a classical method, used in the majority cochlear centers in the world. This is not a suitable method in case of chronic otitis media and middle ear malformation. In these cases Colletti proposed the middle fossa approach and cochlear implant insertion omitting middle ear structures. In patient with bilateral chronic otitis media underwent a few ears operations without obtaining dry postoperative cavity. Cochlear implantation through the middle fossa approach was performed in this patient. The bone fenster was cut, temporal lobe was bent and petrosus pyramid upper surface was exposed. When the superficial petrosal greater nerve, facial nerve and arcuate eminence were localised, the cochlear was open in the basal turn and electrode were inserted. The patient achieves good results in the postoperative speech rehabilitation. It confirmed Colletti tesis that deeper electrode insertion in the cochlear implantation through the middle fossa approach enable use of low and middle frequencies, which are very important in speech understanding.

Purification and properties of deoxyribonucleic acid binding factor isolated from the surface of Streptococcus sanguis cells.

Deoxyribonucleic acid (DNA) binding factor (BF) was found in surface fluids from competent and noncompetent cells of Streptococcus sanguis strains Challis, Wicky, and Blackburn. Fluids from noncompetent cells exhibited about 10% BF activity compared with extracts from competent cells. BF from competent Wicky cells was purified to homogeneity by electrophoresis and immunodiffusion. Purified BF preparations exhibited slight endonucleolytic activity, directed mainly against single-stranded DNA. Nucleolytic and DNA binding activities present in purified BF could be separated by polyacrylamide gel electrophoresis. Purified BF was sensitive to proteolytic enzymes and to phospholipase D, and its activity was stimulated in the presence of low Triton X-100 concentrations. The protein component of BF is a single, monomeric polypeptide with a molecular weight of 56,000 and an isoelectric point of pH 5.8. Binding of purified BF to DNA was a very rapid process at the optimum temperature, pH, and ionic strength and led to the formation of fast-sedimenting complexes. Purified BF was tested for several properties. It exhibited higher affinity to single- than to double-stranded DNA. It bound poorly to glucosylated phage T4 and single-stranded, synthetic polydeoxyribonucleotides and did not bind to RNA. It protected single-stranded DNA against nuclease S(1) action but did not protect native DNA against deoxyribonuclease I action. No evidence was found for unwinding activity, using double-stranded DNA as a substrate.