Fitness to fly for children and adolescents after Fontan palliation.

Introduction: At cruising altitude, the cabin pressure of passenger aircraft needs to be adjusted and, therefore, the oxygen content is equivalent to ambient air at 2,500 masl, causing mild desaturation and a rising pulmonary vascular resistance (PVR) in healthy subjects. For Fontan patients with passive pulmonary perfusion, a rising PVR can cause serious medical problems. The purpose of this fitness to fly investigation (FTF) is to assess the risk of air travel for children and adolescents after Fontan palliation. Methods: We investigated 21 Fontan patients [3-14y] in a normobaric hypoxic chamber at a simulated altitude of 2,500 m for 3 h. Oxygen saturation, heart rate, and regional tissue saturation in the forehead (NIRS) were measured continuously. Before entering the chamber, after 90 and 180 min in the hypoxic environment, blood gas analysis and echocardiography were performed. Results: Heart rate and blood pressure did not show significant intraindividual changes. Capillary oxygen saturation (SaO2) decreased significantly after 90 min by a mean of 5.6 ± 2.87% without further decline. Lactate, pH, base excess, and tissue saturation in the frontal brain did not reach any critical values. In the case of open fenestration between the tunnel and the atrium delta, P did not increase, indicating stable pulmonary artery pressure. Conclusion: All 21 children finished the investigation successfully without any adverse events, so flying short distance seems to be safe for most Fontan patients with good current health status. As the baseline oxygen saturation does not allow prediction of the maximum extent of desaturation and adaption to a hypoxic environment takes up to 180 min, the so-called hypoxic challenge test is not sufficient for these patients. Performing an FTF examination over a period of 180 min allows for risk assessment and provides safety to the patients and their families, as well as the airline companies.

The influence of pre- and intraoperative positioning of the condyle in the centre of the articular fossa on the position of the disc in orthognathic surgery. A magnetic resonance study.

OBJECTIVE: We investigated the changes in the temporomandibular joint (TMJ) after bilateral sagittal split osteotomy of the mandible for orthognathic surgery and the influence of positioning of the condylar process in the centre of the articular fossa before and during the operation for preventing changes in the TMJ postoperatively. STUDY DESIGN: A total of 28 patients with mandibular retrognathism had bilateral sagittal split osteotomies for mandibular advancement. In one group of 14 patients (28 TMJ), the condyles were placed in the centre of the articular fossa before and during the operation, and in the other group they were not. Differences on magnetic resonance imaging (MRI) were calculated and the results were evaluated. RESULTS: The main differences were found at maximal mouth opening. 15/28 TMJs (54%) that had not been positioned changed the position of the disc from physiological to anterior disc derangement with and without reduction postoperatively. In the 28 that had been positioned, changes were found in only 3 TMJs (11%) postoperatively. CONCLUSIONS: Fixing the condylar process in the centre of the articular fossa intraoperatively before bilateral sagittal split osteotomy is a factor in preventing postoperative structural changes in the temporomandibular joint.

[Stimulating regeneration of bone defects by implantation of bioceramics and autologous osteoblast transplantation]. / Stimulation der Regeneration von Knochendefekten durch Einsatz einer Biokeramik und autologer Osteoblastentransplantation.

QUESTION: Does artificial stimulation of osteoconduction and osteogenesis lead to improved bone formation in defects of critical size? MATERIAL AND METHODS: Full-thickness, critical-sized defects in the anterior mandible were created in 24 adult mini-pigs. These defects were treated with a new kind of bioactive ceramic (60% hydroxylapatite and 40% beta-tricalcium phosphate), applied as a unique sol gel [9]. The bioceramic was tested alone and in combination with autologous osteoblasts. In a control group, periosteum was the only bone-producing source. After 5 weeks, the animals were sacrificed and the defects analyzed clinically, histologically, and by X-ray examination. The effects of periosteum, bioceramics, and osteoblasts were investigated in particular. RESULTS: The new bioceramic was degraded at the same speed as new bone was laid down. The rate of newly formed bone was highest in the bioceramic group at 72.3% (control group with periosteal covering only 59.3%). Additional transplantation of autologous osteoblasts did not result in faster bone production. CONCLUSION: It seems that this bioactive ceramic is successful as a bone replacement material and will be suitable as a carrier for osteoinductive substances such as bone morphogenetic proteins.

Impact of prednisone on TGF-beta1 and collagen in diaphragm muscle from mdx mice.

The purpose of this study was to assess the impact of prednisone treatment for 8 weeks on the level of transforming growth factor-beta 1 (TGF-beta1), hydroxyproline (HYP) concentrations, and level of the mature, nonreducible collagen cross-link hydroxylysylpyridinoline (HP) in diaphragm muscle from 12-week-old mdx mice. Diaphragm muscle from untreated mdx mice had a significantly higher level of TGF-beta1, HYP, and HP cross-link compared with normal C57BL/10J (control) mice. Prednisone treatment significantly reduced the level of TGF-beta1 and HYP in diaphragm from mdx mice to values similar to control mice, but resulted in a higher level of the HP cross-link compared with untreated mdx mice. These findings indicate that short-term treatment of mdx mice with prednisone can attenuate the fibrotic response in diaphragm muscle, possibly by mediating the level of TGF-beta. Although prednisone was beneficial in preventing collagen accumulation, it resulted in a higher level of the HP cross-link, presumably by decreasing collagen turnover

The period of latency before a muscle receptor generates an action potential as a response to a muscle stretch.

Six primary (Ia) and seven secondary (II) muscle spindle afferents and eight Golgi tendon organ afferents (Ib) from the tibial anterior muscle of the cat, recorded at the dorsal roots, were subjected to a sinusoidal stretch of the host muscle, the frequency of which increased linearly from 2 to 80 Hz over four different lengths of time. Both the amplitude of the sinusoidal stretch and the prestretch of the muscle were varied. The phase of the action potentials was determined. The phase of the action potential, driven 1:1, increased linearly with frequency. From the gradient of the phase of this action potential the muscle-muscle receptor latency was determined, i.e., the period of latency between the stretch of the muscle and the occurrence of the action potential at the muscle nerve where it enters the muscle. The muscle-muscle receptor latency had values lying between 3 and 8 ms: it was dependent on the experimental parameters and became shorter as the conduction velocity of the afferent fiber increased. In three experiments the muscle latency was determined, i.e., the period of latency before the stretch was transferred from the tendon of the muscle to the proximal third of the muscle belly. The muscle was stretched sinusoidally under the same varying parameters as given above. The length changes occurring in the proximal third of the muscle were measured with a piezo element. The muscle latency was determined from the slope of the phase of the zero points of the sinusoidal piezo length changes; the phase increases linearly with frequency. The muscle latency had values lying between 6 and 15 ms: it was dependent on the experimental parameters. The muscle spindle latency, i.e., the period of latency between the stretch of the polar parts of the intrafusal muscle fibers and the recording of the action potentials from the spindle nerve near the spindle capsule, was determined from 5 Ia fibers and 1 II fiber of isolated muscle spindles. The isolated muscle spindle was stretched under the same varying parameters as given above. The muscle spindle latency was determined from the slope of the phase of the phase-locked action potential. The muscle spindle latency as measured by our method proved to be 0 ms. The latencies of the three elements and their dependence on the experimental parameters are discussed in the light of the transfer properties of the muscle and the muscle receptors.

Dental implants in alveolar cleft patients: a retrospective study.

Since 1994, 15 cleft patients have received dental implants after treatment of the alveolar clefts by osteoplastic measures. Altogether 23 dental implants were undertaken. Twelve implants were inserted after tertiary osteoplasty, 7 with simultaneous repeat-osteoplasty, and another 4 implants following two-stage re-osteoplasty. In 11 patients with a total of 17 implants clinical and radiological follow-ups were performed. An individual crown was constructed on each of the implants. The radiological evaluation revealed that 70% of the implants were fully embedded in bone. All implants except one remained in situ and stable. Thus, the success rate was 96% retention. It is believed that a dental implant in the alveolar cleft may be lost because of its unfavourable location in terms of stability and function or because it was inserted too late. Scars resulting from previous surgery can also play a role in the failure of an implant. Therefore it is proposed that dental implants should not be inserted later than 6 to 8 weeks following osteoplasty of the cleft alveolus.

Incidence of velopharyngoplasty following various techniques of palatoplasty.

A total of 474 patients with cleft palates were treated at the Department for Maxillofacial Surgery of Rostock University from 1971 to 1991. In 145 cases velopharyngoplasty was indicated. Primary velopharyngoplasty was performed on 36 and secondary velopharyngoplasty on 109 patients. In our opinion today primary velopharyngoplasty should be the exception. Intravelar veloplasty according to Kriens (1970) created particularly favorable conditions for good velar function so that secondary pharyngoplasty was only rarely indicated. Secondary pharyngoplasty should be performed and timed only in agreement with the speech therapist.

[Fractures of the facial skull in the growth period and concomitant injuries]. / Gesichtsschädelfrakturen im Wachstumsalter und ihre Begleitverletzungen.

From 1968 to 1990, 135 children up to the age of 14 years were treated as in-patients for fractures of the facial skull. Most had been sustained in traffic accident. Other associated lesions were seen in 80 patients. In 21 of these we observed general surgical traumas or fractures of the base of the skull, and in 23 patients cerebral traumas were detected. Treatment was instituted an average of 1.7 days after the trauma in the case of patients with no associated injuries and of 5.6 days in the case of those with other injuries. Definitive treatment had been applied within 6 days after the accident in 80% of patients with other injuries and/or with fractures of the skull base.

[The late results following velopharyngoplasty. A data comparison of the 2 cleft centers of Hamburg and Rostock]. / Spätergebnisse nach Velopharyngoplastik. Datenvergleich der zwei Spaltzentren Hamburg und Rostock.

Speech results were evaluated in 349 patients following velopharyngoplasty in all cases according to Sanvenero-Rosselli. Velopharyngoplasty was performed several years after palatoplasty in either the Rostock or the Hamburg cleft centers. Comparison of the data revealed that the outcome after velopharyngoplasty in relation to speech was more or less the same in the patients from both centers. In 90% of the patients with clefts of the lip, alveolus, and palate, and in over 90% of those patients with only cleft palates, voice sound was at a level between 1 and 2 on a scale to 3 and on average levels of 1.46 and 1.53 were achieved. These results document that the surgery, when combined with close interdisciplinary team work with the speech therapist, culminated in the successful rehabilitation of cleft patients at both cleft centers.

The prosecution of assaultive clients: treatment considerations.

While some claim that the risk of serious injury to mental health staff members from client assault is minor, others suggest that assaultive episodes have been underreported. With rising pressure from the legal system to hospitalize the more dangerous clients, the increased potential for staff injury necessitates interventions to prevent and deal with client violence. Legal prosecution of violent clients is one nontraditional, and possibly overlooked, intervention. The author reviews the strengths and weaknesses of this approach, as well as implications for clinical practice and empirical research.

[The Helkimo index for assessing treatment results after mandibular fractures]. / Der Helkimo-Index als Beurteilungsmöglichkeit der Behandlungsergebnisse von Unterkieferfrakturen.

Based on the Helkimo index we assessed the success of conservative and conservative-surgical forms of treatment for mandibular fractures in a total of 166 patients. The control group consisted of 50 probands. The Helkimo dysfunction index, which is based on various criteria, showed dysfunction in 81.9% of the patients with only slight functional impairment in 57.2% of these cases. 18.1% of the patients were clinically symptom-free. A comparison with the probands revealed no major differences in dysfunction between the two groups. Significant differences were observed only in the case of 2 isolated criteria (maximum mandibular protrusion, muscle pain). Severe dysfunction, however, was more common in the fracture patients. Based on the Helkimo occlusion index disorder were noted in 91.7% of the patients, while severe occlusion disorder were observed particularly in patients with combined mandibular body and condyle fractures (40.0%). In the control group a more favorable occlusion index was found to be due mainly to the greater number of present and/or occluding teeth. The Helkimo index, particularly the dysfunctionindex, is a very useful instrument for assessing the success of treatment measures in mandibular fracture cases. It should be more commonly used to improve the possibilites of objective comparisons between patients from different hospitals.

Incidence of cleft lip, alveolus and palate forms.

The different cleft forms of 1,450 cleft lip, alveolus and/or palate patients have been analyzed. Randomized groups of 50 plus the next 50 patients and so forth have been examined. The resulting 29 groups reveal a maximum of 139 different clinical cleft forms. The prediction of a possible maximum was made with the exponential formula y = a. (1-eb.x). The tendency of the prognosis levels at a maximum of 169 different cleft forms in and above 4900 patients.

[Success rates of midfacial fracture treatment]. / Erfolgsbewertung der Therapie von Mittelgesichtsfrakturen.

295 patients with midfacial fractures were treated on an inpatient basis between 1975 and 1989. 185 patients underwent a follow-up examination. Discomfort was reported by patients in 43% of the cases, whereas pathological clinical findings were observed in 39% of the patients followed up. The late sequelae, which were only slight in extent, were increasing in frequency with the severity of the injury. The use of miniplate osteosynthesis resulted in improved clinical results. Apart from early diagnosis, immediate referral to a specialized hospital and immediate therapy, more emphasis must be placed on interdisciplinary cooperation.

[Late results of corrective surgery of protruding external ears]. / Spätergebnisse von Korrekturoperationen abstehender Ohrmuscheln.

In the period 1974-1984 corrections of the external ear were carried out on 343 patients using the Haecker/Joseph method for flattening and the Converse method for anthelixplasty. Check-ups on 147 patients revealed late results to be "improved to very good" in 92.5% of cases on the basis of metrical data and aesthetic appraisal of the corrected external ear. Provided that there is a firm indication and exact pre-operative diagnosis combined with good surgical technique and post-operative care, these two methods represent well-tried procedures with a high success rate.

[Experimental animal studies on the possibilities of bone reconstruction using preserved allogenic material]. / Tierexperimentelle Untersuchungen zu Möglichkeiten der Knochenrekonstruktion durch allogenes konserviertes Material.

Preserved allogeneic bone is possibly to repair the permanent shortness in autogeneic bone tissue in clinical practice. Complications as to the incorporation were observed after using lyophilised allogeneic implants. These were attributes to immunologic defense reaction. Demineralised bone caused a more intensive bone regeneration histologically than lyophilised bone. The clinical test of a superficial demineralised lyophilised preserved bone with osteoinductive potency and structural stability is recommended.

[The results of sagittal mandibular splitting with traction screw osteosynthesis in the surgical correction of progenia]. / Ergebnisse der sagittalen Unterkieferspaltung mit Zugschraubenosteosynthese bei der operativen Korrektur von Progenien.

Sagittal split osteotomy by Obwegeser and Dal Pont with lag screw osteosynthesis by Spiessl is a promising method of treatment for the surgical correction of progenia. Functional and aesthetic results of this method are well. Lesions of the mandibular nerve require subtle technique of operation.