Search PubMed⌕ Search

Biomedical subjects

R Klöppel

Publications and source records attributed to R Klöppel.

At least 19 recordsLinked to original sources

[Distraction osteogenesis in the treatment of severe midfacial hypoplasia].

PATIENTS: Between May 1998 and May 2002, 38 patients suffering from severe midfacial retrusion and atrophy were treated by way of midfacial distraction osteogenesis. Diagnoses included cleft lip and palate (32 patients) and one case of Crouzon's disease. Ages ranged from 6-65 years. A total of 28 patients presented a velopharyngeal flap and nine patients were almost or fully edentulous. Using an extraoral halo device, distraction was performed after a subtotal Le Fort-I/II/III or modified quadrangular osteotomy. RESULTS: Distraction ranged from 9 to 31 mm (17 mm average). Following the primary operation, seven patients underwent a second intervention due to problems with the procedure or the device. Two patients needed a secondary Le Fort-I-osteotomy. With respect to velopharyngeal insufficiency, 21% showed a deterioration and 8% an improvement. Postoperatively, a decrease of 15-20% in the attained sagittal advancement was seen during the first 6 months. This was attributed to relapses and postoperative orthodontics. Thereafter skeletal stability was maintained. CONCLUSION: Distraction osteogenesis of the midface can be the method of choice in severe midfacial retrusion. Due to the difficult patient situation and the technical intricacies a higher complication rate has to be accepted than for conventional dysgnathia operations.

Adolescent↗

[Early clinical management after polytrauma with 1 and 4 slice spiral CT].

In the early clinical phase the comprehensive imaging of patients with multiple trauma using helical CT is already established. Aim of this study was to assess whether MSCT may improve the patient management and the diagnostic results. The procedure is designed as follows: after life-thretening treatment x-ray of chest and ultrasound are carried out in the emergency room. Then the patient is moved to CT. From 1998 to december 2000 241 patients were examined using a single slice helical CT (Somatom plus 4), in 2001 79 patients using a 4-slice helical CT (Somatom VZ, Siemens Med.Sol.). After CT selected radiograms of the extremities were taken. 359 of 360 procedures were carried out successfully. Excluding 1 case (death during 1-sl.h CT) all relevant lesions of head, neck, and body were diagnosed. Although the patients had an injury severity score of approximately 30. The change from 1 slice-helical CT to 4 slice-helical CT allowed us to reduce the stay in the CT room from 28 to 16 min. The total lethality decreased by approximately 4%. Advantages for the patient arose from the standardized examination protocol using multislice CT. If integrated in an interdisciplinary management concept, it is a good compromise between examination time, comprehensive diagnostic imaging, life-saving therapeutic procedures, and therapy planning.

Efficiency, Organizational↗

[Invasive pulmonary aspergillosis--CT findings in context with the clinical course].

PURPOSE: To investigate the impact of chest radiographs and CT in patients suffering from invasive pulmonary aspergillosis (IPA) compared to the clinical course. PATIENTS AND METHODS: Twenty-three patients with confirmed diagnosis of IPA between January 1996 and September 1999 were included in this study. Signs of inflammatory infiltrates on chest radiographs and CT were retrospectively evaluated in relation to the onset of the clinical symptoms. Infiltrates on CT were analyzed in detail with respect to number, morphology, and localization. RESULTS: Seventy-six infiltrates were found on the CT of 22 patients; one patient had diffuse areas of lung infiltrates. Both lungs were affected by infiltrates in 14 patients. Pleural effusions were confirmed in 12 patients. Twelve patients had typically round foci with halo and nine patients crescent air signs. The preferred localization of lung infiltrates was segment 6. The median interval between the onset of clinical symptoms and the first radiographic changes was 5.5 days, with an additional interval of 4.5 days until confirmation by CT. Localization, number of infiltrates, and clinical course were not related. CONCLUSION: In immune-compromised patients with fever, a CT of the chest should be carried out as soon as possible to detect signs indicative of IPA. Morphological changes on CT like a round focus with halo and crescent air sign support the diagnosis of IPA. In this context, special attention should be directed to pulmonary segment 6.

Aspergillosis↗

[CT-guided marking of lung lesions before minimally invasive operation].

Video-assisted thoracoscopic surgery (VATS) is an established method for resection of suspicious pulmonary lesions. However, there are problems to detect small subpleural lesions. A procedure for localization of such lesions will be demonstrated. Since may 2000 our experience includes 5 patients (4m, 1f) suffering from solitary pulmonary lesions. In preparation of VATS a CT-guided marking was carried out using both a lasermarker system as well as a special marker system for lung lesions. All 5 procedures were successful. With the laser system the pulmonary nodule was exactly marked and the special wire was placed without any complications. Consequently, the pulmonary nodule was fixed. During video-assisted wedge resection the nodule can be tracted outside. Operating time was reduced in comparison to time consuming search of unmarked lesions. The combined application of CT-guided marking, transthoracic fixation of pulmonary nodule and VATS is recommended preoperatively. It should apply in lesions, which are located subpleural and thoracoscopically not visible.

Adult↗

[Functional spiral CT in after-care of irradiated laryngeal carcinomas].

The importance of spiral-CT is clinically accepted for diagnosing spreading disease and for making a decision about the therapy strategy for head and neck tumors. Its importance for follow-up after radiotherapy was examined in 26 patients with irradiated laryngeal tumors. Using spiral-CT multiple signs of alterations (n = 98) can be diagnosed, which are not only important for tumour relapse, but also for assessment. Spiral-CT offers the possibility of achieviny various additional information about the larynx that cannot be obtained with laryngoscopy. In follow-up examinations after radiation, laryngoscopy and spiral-CT are recommended as an integrated neck examination using the breath-holding technique (separately reconstructed) and also as functional spiral-CT of the vocal cords in "I"-phonation.

Aftercare↗

[Callus distraction of the midface. Requirements for diagnostic imaging].

Callus distraction of the midface is a recently developed surgical method for treatment of atrophic or hypoplastic maxillae. The treatment planning is based on individual shaped models, being constructed with the help of computed tomographic data. Our experience is based on 10 patients (3 male/7 female; age: 11-55 years). The demands for imaging are reported. The following imaging procedure is recommended: 1. preoperative: lateral x-ray, orthopantomogram, spiral CT, 2. during the time of callus distraction with normaly takes 4 to 5 weeks: lateral x-ray (every 10 days), and 3. for follow up: lateral x-ray and spiral CT. The Radiation exposure caused by the repetitive images is calculated in detail.

Abnormalities, Multiple↗

[Functional spiral CT in after-care of irradiated laryngeal carcinomas].

The importance of spiral-CT is clinically accepted for diagnosing spreading disease and for making a decision about the therapy strategy for head and neck tumors. Its importance for follow-up after radiotherapy was examined in 26 patients with irradiated laryngeal tumors. Using spiral-CT multiple signs of alterations (n = 98) can be diagnosed, which are not only important for tumour relapse, but also for assessment. Spiral-CT offers the possibility of achieving various additional information about the larynx that cannot be obtained with laryngoscopy. In follow-up examinations after radiation, laryngoscopy and spiral-CT are recommended as an integrated neck examination using the breath-holding technique (separately reconstructed) and also as functional spiral-CT of the vocal cords in "I"-phonation.

Adult↗

[In vitro investigations for detection of vascular stenosis using spiral CT angiography].

PURPOSE: This experimental study investigates the suitability of spiral CT angiography for detection of stenoses. MATERIAL AND METHODS: Three vessel phantoms of 4, 7, and 10 mm diameter were scanned with spiral CT several times using different scanning parameters each time. Axial scans were viewed in different ways. Stenoses were adjusted axial, oblique, and parallel to the scan plane, and in between. 7 radiologists had to make a total of 630 decisions about the detectability of stenoses. RESULTS: Adequate scan and reconstructional parameters improve detection of stenoses significantly. 100% recognition can be reached with 5 mm layer thickness and table feed and 2 mm reconstructional interval provided axial scans are viewed in cine mode on a monitor. Vessels running parallel to the layer plane show better results than vessels axial to the plane, which in turn show better results than those running oblique. Vessels of 4 to 10 mm diameter are almost equally suitable. CONCLUSIONS: Viewing axial scans, the detectability is rather influenced by different locations of stenoses than by varying vessel diameters.

Arterial Occlusive Diseases↗

[Spiral CT vesiculography--a new examination technique in patients with histologically verified prostate carcinoma].

PURPOSE: Development of an imaging method for detection of seminal vesicle invasion in patients with histologically proven carcinoma of the prostate. MATERIALS AND METHODS: In 24 patients with histologically proven carcinoma of the prostate we preoperatively performed an antegrade vaso-vesiculography with non-ionic, iodine-containing contrast agent followed by a spiral CT of the seminal vesicles. RESULTS: In 21 patients we achieved both a bilateral and a bulging enhancement of the seminal vesicle lumen. The method is introduced and described in detail. CONCLUSIONS: Intraductal application of contrast agent just before spiral CT results in unfold and bulging enhanced seminal vesicles. From the differentiation of the lumen, the wall, and the surrounding fat of the seminal vesicles as well as the enhanced ejaculatory ducts we expect information on tumorous infiltration in cases of histologically proven carcinomas of the prostate.

Aged↗

Primary amyloidosis of the mesentery and the retroperitoneum presenting with lymphedema.

We report the case of a 57-yr-old woman presenting with moderate weight loss, abdominal distension, and lymphedema of the legs and vulva. Computed tomography of the abdomen revealed massive thickening of the rectal wall, mesentery, and retroperitoneum. Primary amyloidosis was diagnosed by immunohistochemistry from the rectum and duodenum. To our knowledge, lymphedema due to primary amyloidosis has not yet been reported. The diagnosis should be presumed in the case of retroperitoneal thickening and lymphedema and can be established by immunohistochemistry.

Amyloidosis↗

Diagnostic value of 3D CT surface reconstruction in spinal fractures.

Our purpose was to evaluate the diagnostic value of three-dimensional (3 D) CT surface reconstruction in spinal fractures in comparison with axial and reformatted images. A total of 50 patients with different CT-proven spinal fractures were analysed retrospectively. Based on axial scans and reformatted images, the spinal fractures were classified according to several classifications as Magerl for the thoraco-lumbar and lower cervical spine by one radiologist. Another radiologist performed 3 D CT surface reconstructions with the aim of characterizing the different types of spinal fractures. A third radiologist classified the 3 D CT surface reconstruction according to the Magerl classification. The results of the blinded reading process were compared. It was checked to see in which type and subgroup 3 D surface reconstructions were helpful. Readers one and two obtained the same results in the classification. The 3 D surface reconstruction did not yield any additional diagnostic information concerning type A and B injuries. Indeed, the full extent of the fracture could be easier recognized with axial and reformatted images in all cases. In 10 cases of C injuries, the dislocation of parts of vertebrae could be better recognized with the help of 3 D reconstructions. A 3 D CT surface reconstruction is only useful in rotational and shear vertebral injuries (Magerl type C injury).

Humans↗

[Detection of orbital foreign bodies by CT: are plain radiographs of foreign bodies still useful?].

PURPOSE: To prove the visualisation of orbital foreign bodies by CT. MATERIALS AND METHODS: In vitro we examined defined small objects of various materials (metal, wood, glass, stone) which are common as orbital foreign bodies, Density and minimum detectable size were studied. The findings of 27 patients with suspected orbital foreign bodies were compared with the results of plain radiographs, Comberg radiographs, sonography, and surgery. RESULTS: For iron, the minimum detectable size was 0.02 mm3. A differentiation of various materials by CT was not always possible, especially in small objects. There were wide differences in density of wood (-600 HU to +130 HU) according to hardness and water content. The CT scans correctly showed number and location of foreign bodies. Other methods were inferior in detection of foreign bodies. CONCLUSION: In diagnosis of foreign body injuries of the orbit, CT is the imaging method of choice.

Adolescent↗

[CT-guided intervention by means of a laser marking and targeting aid].

PURPOSE: The present study evaluates the use of a laser guidance system for CT-guided intervention. MATERIAL AND METHODS: 94 cases of diagnostic biopsies and lumbar sympathectomies (54 cases with laser guidance system and 40 without) were compared. RESULTS: Using the laser guidance system, the number of control scans decreased by 30 to 50%, and necessary corrections of needle location were reduced by a maximum of 30%. The average target deviation of the needle decreased to less than 5 mm in 50% of cases. CONCLUSION: The laser guidance system is strongly recommended in CT-guided interventions for quality assurance and higher efficiency. The advantage is especially marked if the target area is small.

Adolescent↗

[Spiral computerized tomography diagnosis of abdominal seat belt injuries in children].

Seat belt injury (s.b.i.) arises from not properly applied seat belt in case of car accidents. The importance of spiral CT for the diagnosis of s.b.i., especially of hidden traumatic lesions, will be demonstrated. Our experience includes 9 children in the age of 4 to 13 years suffering from life-threatening s.b.i. After life-saving treatment we took a spiral CT (Somatom plus S): first spiral CT, 10 mm slice thickness, without contrast medium (c.m.) and second spiral CT, 5 mm slice thickness, start delay 35-45 s after a large volume of c.m. Of these, 8 of 9 children survived. Besides bruising signs head injuries, and knee joint lesions in 4 of 9 cases, a combination of ruptured duodenum, ruptured liver or spleen, and chance fractures of the spine was found which is typical for s.b.i. In the remaining 5 cases, two of the lesions were combined. Rupture of the small bowel was manifested mainly as the discrete finding of free air or inhomogeneous ascites with a high density (bowel contents mixed with blood). Not only the emergency doctor but also the radiologist should take into account the complexity of seat belt injuries. Spiral CT is the imaging method of choice in the case of polytraumatic children.

Abdominal Injuries↗

[Contrast medium administration in spiral computed tomography: the results of a consensus conference. Institute for Radiodiagnosis, Regensburg].

The rapidity of spiral (helical-) computed tomography requires new protocols for i.v. contrast media administration. Flow rate, volume and delay are discussed controversially in the literature. Hence, a consensus meeting was initiated. In this meeting, problem related questions were designed, discussed and answered using a digital vote system. Spiral-CT-technology was found to be the ideal examination technique for thorax, liver, pancreas, kidney and the retroperitoneal space with an overall agreement between 89 and 97%. The exclusive use of nonionic contrast media and power injectors was recommended by 100% of the participants. More than 90% of the contributors did not accept native scans only for examinations of the neck, thorax, liver, pancreas, kidney and the retroperitoneal space. Regarding volume, flow rate, delay and physical CT-parameters the agreement laid between 50 and 100%. The meeting concluded that randomised controlled studies should be performed to evaluate detailed contrast media protocols for helical CT.

Berlin↗

[Functional spiral CT of the larynx].

Imaging of the larynx by computed tomography has reached a new quality through spiral CT. Its significance for evaluation of vocal cords function is examined with 10 patients with glottic tumours before, during and after radiation therapy. The spiral CT procedure which complements laryngoscopy is described: Gantry tilt 10 degrees caudal, two spiral CT starting at the cricoid cartilage with 3 mm slice thickness and pitch 1, one with flat breathing and one with "1" phonation; overlapping reconstruction with large zoom factor, secondary reconstruction image reformating.

Humans↗

[Acute abdomen in extensive thrombosis in the inferior vena cava collateral circulation].

Variations of the inferior vena cava (IVC) because of either embryonal malformations or postthrombotic changes are not uncommon. The clinical symptoms include repetitive thrombotic events. We report on an atypical case of acute abdomen resulting from thrombotic occlusion of the IVC and the right renal vein as well as of the collateral vessels.

Abdomen, Acute↗