Comparative Analysis and Long-Term Results of Various Septal Extension Graft Types.

Shape, tip projection, and position can be controlled by the use of septal extension grafts (SEG). A retrospective cohort study of patients undergoing primary and secondary rhinoplasty was reviewed. The purpose of this study was to analyze maintenance of nasal length, dorsal length, and nasolabial angle postoperatively comparing different types of SEG using standardized photography and digital measurement. Two-hundred twenty-one patients undergoing rhinoplasty were included. There was a statistically significant change regarding the nasolabial angle during the time of follow-up decreasing from 97.53 to 95.30 degrees. No changes could be found in dorsal and nasal length. There was no significant difference among the techniques used to fixate the SEG. The nasolabial angle appeared to decrease from the position 2 weeks postoperatively without changes in the dorsal and nasal length. This means that the decrease in the nasolabial angle depends on the swelling effect and not on drooping of the tip confirming the reliability of SEG over time.

[New clinical applications for laser Doppler vibrometry in otology]. / Neue klinische Anwendungen der Laser-Doppler-Vibrometrie in der Otologie.

BACKGROUND: An instrument to measure vibration in the middle ear needs to be sensitive enough to detect displacement on a nanometer scale, yet not affect the vibration itself. Numerous techniques have been described in the literature, but laser Doppler vibrometry (LDV) has nowadays become established as the standard method in hearing research. OBJECTIVE: This article aims to present possible clinical applications of an LDV system in otology. MATERIALS AND METHODS: A commercially available single-point vibrometer was used. Measurements were carried out both with the sensor head mounted on an operating microscope and as a handheld device with the sensor head manually inserted in the ear canal. For the latter, a custom-made unit containing an electrically tunable lens was attached to the sensor head. Middle ear vibrations were measured in a temporal bone model as well as in patients during and after implantation of a Vibrant Soundbridge (VSB; MED-EL Corp., Durham/NC, USA). RESULTS: Different types of middle ear pathologies can be distinguished by the frequency response of the umbo. The LDV technique can be used for intraoperative quantification of the coupling quality of the VSB's Floating Mass Transducer (FMT; MED-EL) to the ossicle chain during VSB implantation. Postoperatively, the method serves as a follow-up testing tool if a deterioration in aided hearing threshold occurs. The measurement can reveal changes in the umbo transfer function, e. g., due to middle ear scarring or dislocation of the FMT. CONCLUSION: Many clinical questions in otology can be addressed by LDV. However, due to the high acquisition costs of an LDV system, the relatively large instrumental setup, and the large inter-ear variability of middle-ear function, the technique has not (yet) become established in clinical routine.

Reversing the pump dependence of a laser at an exceptional point.

When two resonant modes in a system with gain or loss coalesce in both their resonance position and their width, a so-called exceptional point occurs, which acts as a source of non-trivial physics in a diverse range of systems. Lasers provide a natural setting to study such non-Hermitian degeneracies, as they feature resonant modes and a gain material as their basic constituents. Here we show that exceptional points can be conveniently induced in a photonic molecule laser by a suitable variation of the applied pump. Using a pair of coupled microdisk quantum cascade lasers, we demonstrate that in the vicinity of these exceptional points the coupled laser shows a characteristic reversal of its pump dependence, including a strongly decreasing intensity of the emitted laser light for increasing pump power.

THz quantum cascade lasers with wafer bonded active regions.

We demonstrate terahertz quantum-cascade lasers with a 30 µm thick double-metal waveguide, which are fabricated by stacking two 15 µm thick active regions using a wafer bonding process. By increasing the active region thickness more optical power is generated inside the cavity, the waveguide losses are decreased and the far-field is improved due to a larger facet aperture. In this way the output power is increased by significantly more than a factor of 2 without reducing the maximum operating temperature and without increasing the threshold current.

[Split thickness skin graft for coverage of soft tissue defects]. / Spalthauttransplantation zur weichteildefektdeckung.

OBJECTIVE: Coverage of skin or soft tissue defects of various sizes by transplantation of spit thickness skin grafts. INDICATIONS: Skin or soft tissue defects of any size or location as long as there is a good blood supply to the wound bed. CONTRAINDICATIONS: Wound bed providing poor blood supply (e.g., tendon or bone), vessels or nerve without soft tissue coverage, any kind of implant material which is not covered by vital soft tissue. Relative contraindications include defect position at the flexion side of joints or other mechanically stressed locations (e.g., heel, neck) and local infection. SURGICAL TECHNIQUE: By meticulous debridement of the recipient site and coagulation of venous bleedings, the recipient site is prepared for skin grafting. Thereafter, the split thickness skin graft is harvested and, if necessary, modified by the meshing procedure. Then, the skin graft is placed in the defect and fixated at the wound margins. To promote healing, a special compression dressing is used to cover the split thickness skin graft. In case of uneventful wound healing, this dressing should be left in place for 5 days. POSTOPERATIVE MANAGEMENT: After removal of the compression dressing, daily changes are done using double layers of fatty gauze, alternated with periods without dressing. In the case of uneventful healing, the skin transplant can be covered starting in week 2 with a thin film of cream ointment. RESULTS: Split thickness skin grafting is a routine maneuver in reconstructive surgery and allows predictable, good results. Partial skin graft losses are mostly due to a combination of inadequate debridement and local infection. If the operation in done technically correct, total graft losses are rare.

[A tongue biopsy led to the diagnosis]. / Die Diagnose liegt auf der Zunge.

A 76-year-old patient in otherwise good health presented with a 2-year history of bilateral painless submandibular swelling and macroglossia. A standard ENT examination revealed no additional symptoms. Tongue biopsy led to the diagnosis of amyloidosis, serum immunofixation identified AL amyloidosis and a kappa light chain gammopathy resulting from multiple myeloma as the underlying cause.

[Avulsion of the inferior rectus muscle due to a dog-bite and reconstruction of its function]. / Durchtrennung des Musculus rectus inferior durch Hundebiss und Rekonstruktion der Muskelfunktion - eine Kasuistik.

BACKGROUND: Injuries of an extraocular muscle or of the globe due to a dog-bite are rare. PATIENT: An 43-year-old patient presented with an orbital dog bite. He had a complete avulsion of the inferior rectus muscle. During the primary surgical repair, the proximal part of the muscle could not be found. The distal part of the inferior rectus muscle was sutured to the tissue in the original region of the retracted inferior rectus muscle. After surgical repair the patient could read without complaint. We explain the unexpected remarkable postoperative result on the basis of high resolution MRI: Although the muscle belly was lost, some parts of the muscle sheath forming connections to Tenon's capsule had remained. These allowed a certain function of the muscle. CONCLUSIONS: If during the primary surgical repair of a traumatic avulsion of an extraocular muscle the proximal part of the muscle could not be found, it is worth to suture the distal part of the muscle to tissues (empty muscle sheath, connections to Tenon's capsule) in the original region of the lost muscle. This prevents a further retraction of the proximal part of the muscle and helps the finding and differentiation of the structures of the muscle during a prospectivly following surgical repair.