PURPOSE: Our goal was to investigate the role of serial dynamic contrast-enhanced SPGR MRI in the nonsurgical follow-up of patients with temporomandibular joint (TMJ) pain. METHOD: Ten patients (10 joints) with internal derangement of the TMJ were imaged with T1-weighted SE and serial postgadolinium SPGR MR pulse sequences. RESULTS: On T1-weighted images prior to treatment, the disk position was normal in one joint and anteriorly displaced without reduction in nine joints. After treatment, the disk remained normally positioned in one joint, was anteriorly displaced without reduction in eight joints, and was anteriorly displaced with reduction in one joint. The dynamic study after treatment showed a decrease in contrast enhancement of the posterior disk attachment in 7 of 10 joints. These seven patients had resolution or reduction in joint pain. CONCLUSION: These results suggest an association between a decrease in contrast enhancement of the posterior disk attachment and resolution or reduction in joint pain. This association was much stronger than the association between the clinical findings and the anatomy of the disk.

Adolescent↗

PubMedDate not supplied

The influence of aging on auditory brainstem response and electrocochleography in the elderly.

Auditory brainstem responses and simultaneous transtympanic electrocochleographies were investigated in 92 subjects aged between 50 and 89 years with normal hearing or mild presbycusis. Subjects were classified into four age-related groups: 16 subjects in the sixth decade, 28 in the seventh decade, 32 in the eighth decade and 16 in the ninth decade. Thirty young subjects with normal hearing aged 20-29 years were chosen as controls. The result showed progressive delay of wave I (or action potential: AP), wave III and wave V and lengthening of the interpeak intervals (IPIs) of waves III-V and I-V in the subjects aged 50-79 years. In the subjects in the ninth decade, shortening of IPIs of waves I-III and I-V was noted in spite of further delays of wave I. The amplitude of APs on electrocochleography decreased in the groups with mild presbycusis. Both the lengthening and shortening of IPIs might be electrophysiological alterations occurring with aging in the central auditory pathways.

Age Factors↗

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Meniere's disease and the mastoid pneumatization.

The size of the mastoid penumatization was radiographically examined and planimetrically measured in the patients with Meniere's disease, patients with other sensorineural hearing loss and clinically ear healthy persons. Law projection was used for the radiographical examination. No statistical differences were seen among the three groups. Meniere's disease and the factors which influence the mastoid pneumatization are discussed.

Adult↗

PubMedDate not supplied

A titanium-nickel alloy intravascular endoprosthesis. In vitro studies.

In order to evaluate the implantation technique and reliability of conversion at different temperatures, a miniaturized intravascular endoprosthesis (IVEP) composed of thermal shape-memory effect TiNi alloy was delivered via a catheter into a 37 degrees C water mock circulatory loop (MCL) with a flow of 100 ml/min. The 2.5 mm diameter wire coil IVEP was torsion reduced to 1.4 mm, mounted on a modified balloon angioplasty catheter, and delivered into the MCL. Shape-memory conversion was activated thermally by injecting normal saline (3, 5, or 10 ml) at 45 degrees, 50 degrees, 55 degrees, 60 degrees, 65 degrees, or 70 degrees C, while the local temperature (Tp) at the endoprosthesis site was monitored by a thermocouple. Inconsistent completed conversions of the IVEP were produced by injecting 10 ml of 60 degrees C, or 5 ml of 65 degrees C normal saline, which raised the Tp to 45 degrees to 53 degrees C. Complete conversion of the IVEP to 2.5 mm was produced consistently by injecting 10 ml of 65 degrees C or 5 ml of 70 degrees C saline, which raised Tp to 55 degrees C for less than 1 sec. This moderate Tp (55 degrees C) for such a short duration was shown to be a reliable method for remote conversion of the IVEP after catheter delivery. Knowledge of the minimum temperature and volume for consistent, complete conversion of the IVEP has permitted simple, safe conversion during in vivo studies. Delivery after balloon angioplasty is envisioned to either treat acute dissection with occlusion or to prevent chronic restenosis, in order to further improve the safety and efficacy of balloon angioplasty procedures.

Alloys↗

PubMedDate not supplied

Hemolysis. A comparative study of four nonpulsatile pumps.

Hemolysis is one of the important performance parameters of blood pumps. However, comparisons of published data are compromised by the different test methods used. This article reports the results obtained when testing four nonpulsatile blood pumps (Roller pump, Biopump Model 600, Biopump BP-80, Hemadyne pump) in the identical test circuit under the same hemodynamic conditions. A closed test circuit was composed of a flexible bag reservoir and two short tubes for connection to the pump head. The priming volume was 1 L, and the total surface area was 950 cm2. Fresh blood from a fasted calf was directly primed into the circuit and maintained at 37 degrees C. It was pumped at 6 L/min for 12 hr against a 100 mmHg afterload. The hemolysis index (HI), defined as grams of hemoglobin released per 100 L pumped, was calculated from a curve fit to the hourly data. Each pump was tested five times. The mean HI obtained ranged from 0.0467 for the roller pump to 0.0076 for the Biopump BP-80. There was no statistically significant difference among the three centrifugal pumps tested.

Animals↗

PubMedDate not supplied