Wound healing: effects of closing tension, zyplast, and platelet-derived growth factor.

Previous studies have shown that beginning 5 to 7 days from wounding, the tensile strength of wounds closed under tension in rats is significantly higher than the tensile strength of wounds closed without tension. This study evaluated the effects of increased closing tension, zyplast implant (ZI), and human recombinant platelet-derived growth factor (PDGF) on the tensile strength of wounds. Six groups of 12 rats each were divided into two main subsets: wounds were closed without tension in three groups and with high tension of approximately 100 g in the three other groups. In both no-tension and high-tension groups, one subgroup received no intervention (controls), one subgroup received ZI (zyplast controls), and one subgroup received ZI-PDGF (ZI used as a carrier for PDGF). Healing was evaluated by tensile strength determinations at 5 days. For the controls, wounds closed under tension showed a trend toward higher tensile strength, but statistical significance was not reached. Compared with controls, tensile strength was 45% lower in the wounds with ZI and closure with tension (P = .0063) and 38% lower in the wounds with ZI and closure without tension (P = .007). Treatment with ZI-PDGF resulted in 69% higher tensile strengths (P = .049) as compared with ZI controls for wounds closed with tension. This study demonstrated the beneficial effect of PDGF in accelerating healing in wounds closed under tension. Although ZI was able to deliver PDGF to the wound, the use of this substance as a carrier is questioned since it was detrimental to healing.

Glomus tumors of the temporal bone: contemporary evaluation and therapy.

Surgical management of glomus tumors of the temporal bone requires accurate preoperative assessment and a knowledge of temporal bone anatomy, contemporary microsurgical techniques, and appropriate postoperative management. Care should be exercised to minimize postoperative neurologic deficit and deformity resulting from surgery of this usually benign lesion. The primary preoperative goal is to determine the extent of the lesion; although the history and physical examination are helpful, radiologic delineation of the tumor is imperative. Recent advances in surgical approaches and techniques have allowed the removal of larger tumors with lessened mortality and morbidity. Our overall experience in this series of glomus tumors leads us to believe that surgical excision is the treatment of choice for the treatment of glomus tumors of the temporal bone.

Pitfalls in the diagnosis of acoustic neuroma.

The patient with an acoustic neuroma may present to the otologist with a variety of clinical features. Classically these include a retrocochlear pattern of sensorineural hearing loss, reduced vestibular response on caloric testing and radiological asymmetry of the internal auditory canals (IAC). The absence of any or all of these features, however, does not exclude the presence of tumour. Five cases are presented to illustrate the potential for diagnostic delay unless a routine battery of investigations is undertaken in patients with neuro-otological disorders. All patterns of subjective audiometry are encountered, auditory brain stem response testing may be unreliable where hearing loss is profound, vestibular testing is normal in half of small tumours and the intracanalicular tumour may be radiologically undetectable unless IAC meatography is employed.