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R Keerl

Publications and source records attributed to R Keerl.

48 records · Page 3Linked to original sources

[Surgical continuing education with multi-media techniques exemplified by endonasal micro-endoscopic pan-sinus operation].

The concept of multimedia involves the integration of various media into a single computer system which, properly configured, permits an interactive approach. Modern computer technology makes it possible to display of varied audio-visual documents on screen and allow the users to work independently and learn at their own pace. Our new teaching multimedia software (available in English or German) illustrates future possibilities for individualized interactive medical education. Required hardware consists of an IBM-compatible PC plus a CD-ROM drive, two speakers, and a special MPEG multimedia board. The program is supplied on a compact disc. The user begins at an introductory screen and works through the technique of endonasal sinus surgery individually and interactively. He can switch between the following chapters by clicking the mouse: an introduction to anatomy of this region, an atlas of computed tomography of the paranasal sinuses, and a chapter dealing with the danger areas. The main chapter contains a video about how to perform endonasal microendoscopic sinus surgery, which we have divided into thirteen sections. Each of these contains a section on dangers and complications with tips on to avoid and correct them (e.g. how to close a dura defect; what to do after damaging the anterior ethmoidal artery). In addition, CT scans of the relevant areas are shown. A special MPEG multimedia board permits full-screen video.

CD-ROM↗

[Imaging time-dependent changes in the nasal mucosa using the most modern morphing software].

Changes in the nasal mucous membrane lasting longer than 1-2 minutes have, until now, escaped dynamic observation. Even the congestion and decongestion of the turbinates during the nasal cycle and after application of vasoconstrictive nose drops have been documented only by instant stills. For this reason, we developed a method which permits documenting time-dependent endonasal mucosal changes with their natural dynamics on time-lapse video film. Instead of primarily recording a continuous video film, we processed instant stills. Computer interpolation of intermediate steps gives the viewer a dynamic impression. As continuous video endoscopy is not feasible, we produced the continuous film by recording video sequences of approximately 30 seconds length in defined time intervals endoscopically, selecting single stills (so-called original photographs) from each sequence, and splicing them, producing the missing intermediate photographs by a special computer technique (morphing), similar to mathematical interpolation. In this way we could demonstrate the changes of the right and left inferior turbinate during a nasal cycle of lasting five hours and the effect of xylometazolin nose drops on the nasal mucosa. The practical value of this technique, lies in the comprehensive realistic observation of dynamic processes of the nasal mucosa with respect to physiology and pathophysiology.

Adult↗

[Behavior of fatty tissue in frontal sinus obliteration].

The purpose of obliterating the frontal sinus is to provide a permanent solution to the underlying problem. The material of choice for obliteration is freshly removed abdominal fat. Using magnetic resonance imaging, one can assess the vitality of fat tissue in an obliterated frontal sinus without surgery. Eight patients ranging in age from 22 to 65 years underwent osteoplastic frontal sinus surgery with fat obliteration. The freshly implanted abdominal fat was postoperatively investigated using magnetic resonance tomography. The magnetic resonance examinations were carried out on a supraconductive 0.5 T Magnet (Gyroscan T S II, Philips Medicine Systems, Eindhoven, Netherlands) with a square head spool. We produced T1-weighted spin echo images (TR: 450-550 ms, TE: 20-25 ms), T2-weighted fast spin echo images or in double echo technique in transverse orientation (Tubo SE or TR-2000-2500 ms, TE: 50, 90 ms) and STIR sequences for fat suppression (TJ: 140 ms, TR: 1400 ms, TE: 30 ms). Our goal was to determine the time-dependent distribution of vital fat or fibrous tissue, development of necrosis, cysts, recurrences, inflammatory complications, or re-epithelization of the frontal sinus. Six to 24 months postoperatively, we found vital fat tissue in only three of eight cases. In the other five cases fat necrosis was present. The frontal sinus was filled by granulation tissue or fibrous tissue (once). It is not yet possible to determine when the fat changes to connective tissue. This process varies between individual patients. All eight patients were free of symptoms.(ABSTRACT TRUNCATED AT 250 WORDS)

Adipose Tissue↗

[Current aspects of frontal sinus surgery. IV: On therapy of frontal sinus osteoma].

Osteomas are the most common benign tumors of frontal sinus. We evaluated 15 patients with osteomas of the frontal sinus who were managed between 1979 and 1992. The average duration of follow-up was 33 months. In 4 cases osteomas were removed completely via the endonasal route using a microscope and endoscope. We recommend performing a frontal sinus drainage-type 3 primarily. Indications are osteomas of the posterior wall of the frontal sinus located close to the infundibulum. For osteomas of the anterior wall and those located laterally or for very large osteomas we prefer the osteoplastic approach. Apart from the excellent exposure this latter procedure also provides good aesthetic results after carefully placed incisions and precise replacement of the bone flap. We recommend the bicoronal incision in patients with large frontal sinuses, women, or in the presence of good hair growth. Incisions are best placed in a frontal crease in patients with hair loss or a, small frontal sinus.

Adult↗

[Current aspects of frontal sinus surgery. I: Endonasal frontal sinus drainage in inflammatory diseases of the paranasal sinuses].

Most conditions of the frontal sinus requiring surgery can now be managed successfully by endonasal procedures. According to Draf, 3 types of frontal sinus drainage occur. Surgical techniques and indications are described. In a retrospective study we evaluated 132/648 patients who were on average 5 years postoperative. Forty-two patients had type 1, 43 patients had type 2 and 47 patients had type 3 drainage. Endoscopy revealed a normal mucosa in 56-67%, whole polyps were found in 9-15%. There was no recurrence of an orbital or endocranial complication. According to our definition of surgical success, there was a success rate of 83.4% with type 1 drainage, 83.7% with type 2 drainage and 89.4% with type 3 drainage. If there was only little chance for successful endonasal surgery with type 3 drainage, an external osteoplastic frontal sinus operation was performed for definitive therapy.

Drainage↗

[Current aspects of frontal sinus surgery. II: External frontal sinus operation--osteoplastic approach].

Most inflammatory diseases of the frontal sinus requiring surgery can now be managed successfully by endonasal procedures. There remain, however, a number of problematic cases in which optimal exposure of the entire frontal sinus is required with possible complete removal of the mucous membrane and sinus obliteration. These remain indications for osteoplastic frontal sinus surgery. Depending on the individual situation, incisions can be chosen that are bicoronal, placed in a frontal crease or positioned below the eye-brow. Surgical techniques are described in detail. Osteoplastic surgery of the frontal sinus with fat obliteration is a reliable and safe method, particularly for management of so-called "difficult" frontal sinuses.

Adipose Tissue↗

[Aspects of frontal sinus surgery. III: Indications and results of osteoplastic frontal sinus operation].

The osteoplastic approach is indicated for frontal sinus surgery if optimal exposure of the entire frontal sinus is required for possibly complete removal of the mucous membrane and sinus obliteration. In a retrospective study we evaluated 75 patients whose osteoplastic frontal sinus operations were performed in Fulda between 1979 and 1992 and examined indications for surgery, complications and outcome. All patients were examined clinically and subjective complaints were recorded. Indications for surgery were trauma (43), acute and chronic infections (19), tumors (11) and sinus pneumatoceles (2). The overall aesthetic and functional outcome was excellent. Revision was necessary in one only patient, who had forced air into his frontal sinus by nose-blowing too early to create a threat of infection. No serious complications occurred, such as surgery-related meningeal injury or impaired or double vision. One patient needed a blood transfusion because of hemorrhage due to operation (1.3%). The main advantage of the coronal incision used was preservation of the supraorbital nerve bundle without subsequent nerve dysfunctions. Besides optimal exposure of the whole frontal sinus, precise replacement of the osteoplastic flap and choice of incision also lead to a good aesthetic result.

Abscess↗

[Multi-media technique applied to surgical education].

Multimedia technique applied for surgical training: the microscopic-endoscopic sinus surgery. Multimedia technology is characterised by the integration of several communication media and by an interactive access. New or difficult surgical techniques are made easier and safer thanks to a new program developed for training microscopic-endoscopic sinus surgery.

Computer-Assisted Instruction↗

[The emergency: traumatic aneurysm in the area of the head-neck].

Bleeding of aneurysm of cervical arteries is an emergency situation in ENT surgery. Compression of trachea and big cervical veins together with blood loss needs immediate treatment. Three cases are demonstrated presenting diagnostic and therapeutic management of one spontaneous respectively posttraumatic aneurysm of the inferior thyroid artery, and two aneurysms of lingual respectively facial artery after tonsillectomy. Interventional angiography plays an important role in overcoming such problems. Intravasal application of a platinum coil stops bleeding of the aneurysm and surgical revision of the neck can be avoided.

Adenoidectomy↗

Endonasal microendoscopic pansinusoperation in chronic sinusitis. II. Results and complications.

PURPOSE: We evaluated the long-term results and complications of endonasal pansinusoperation in chronic polypoid sinusitis. PATIENTS AND METHODS: In a retrospective study, 170 patients were followed-up for 20 months to 10 years after bilateral endonasal microendoscopic pansinus surgery or ethmoidectomy. The follow-up consisted of a standardized questionnaire and clinical examination with the flexible endoscope. RESULTS: We found that 85.6% of the ethmoid cell systems, 69.4% of maxillary sinuses, and 37.5% of frontal sinuses could be visualized endoscopically. The ethmoid mucosa was normal in 56% and thickened in 19%. Recurrent polyps were found in 25%. The evaluation--as per the graduation of results defined by us as a combination of examination findings and subjective assessment of the operative result--resulted in an operative success of 92%. Two studies dealing with the frequency of complications showed injury to the dura in 2.3% to 2.55% and periorbital injury without permanent sequelae in 1.4% to 3.4%. Because of two cases of bleeding from the internal carotid artery, the problems of vascular complications in particular will be thoroughly discussed. CONCLUSION: More than 90% of patients with chronic polypoid sinusitis gain long-term satisfying results after endonasal ethmoidectomy with microscope and endoscope. For minimizing the risk of injury of the optic nerve or the internal carotid artery preoperative, computed tomography is necessary. A special training program is recommended.

Chronic Disease↗

Packing in endonasal surgery.

Nasal packing is used to control bleeding in epistaxis and after endonasal surgery, for internal stabilization, and to prevent synechiae or restenosis, particularly after surgery. Generally accepted standards regarding the materials that should be used for packing, how long the packing should be left in place, or the indications for nasal packing are lacking. In view of the present lack of standardization and the many different packing materials used, we review the currently available materials and outline their respective properties, indications, and risks.

Bandages↗