[A 67-year old man with epigastric pain]. / 67-jähriger Patient mit epigastrischen Schmerzen.

A 67-year-old man suffering from epigastric pain showed a phytobezoar in the endoscopy. Therapy with Coca Cola® and enzymes was initiated. The (partial) lysis led to a migration of the bezoar into the ileum, resulting in a small bowel obstruction. After removal of the remaining bezoar via ileotomy a secondary pneumatosis intestinalis occurred. As a rare finding the (phyto-)bezoar should be considered as a differential diagnosis of abdominal pain - especially considering the rising numbers of bariatric surgery, which is a potential risk factor. Furthermore, intestinal obstruction after migration has to be considered as a relevant complication of treatment.

An alternative classification of incisional hernias enlisting morphology, body type and risk factors in the assessment of prognosis and tailoring of surgical technique.

Incisional hernias occur in 5-10% of patients who have undergone laparotomy and are associated with a high morbidity and significant socioeconomic costs. Better understanding of the anatomy and improved methods for reinforcement of the abdominal wall with alloplastic meshes have reduced the recurrence rate to 1-10% depending on the type of hernia and the technique employed. A number of surgical repair techniques and mesh types are available. However, precise criteria for incorporating patient body type, risk factors for recurrence, hernia morphology, and the available biomaterials into planning of the surgical approach (open versus laparoscopic) have yet to be established. The elaboration of such criteria would require comparative evaluation of long-term results in a sufficiently large number of patients, e.g. in multicentre trials or meta-analyses of standardised data from different centres. Current classifications have the drawback that they fail to take account of prognostically relevant risk factors for recurrence and are not self-explanatory. The authors present a classification of incisional hernias that is self-explanatory and practicable in routine clinical practice. Based on the cornerstones of morphology (M), hernia size in cm (S), and risk factors for recurrence (RF), the scheme enables easy description and documentation of the hernia, and provides evidence for the indications and limitations of the main surgical repair techniques. Since randomised studies can scarcely be conducted on incisional hernias due to the numerous morphological variables, the classification presented here may offer an alternative means for comparative data analysis.

The advantages and disadvantages of nerve monitoring during thyroid surgery in childhood.

BACKGROUND: Intraoperative damage of the recurrent laryngeal nerve (RLN) and the external branch of the superior laryngeal nerve (EBSLN) are common and cause complications in thyroid surgery. The method of intraoperative electrophysiological neuromonitoring (IONM) of the RLN and the EBSLN has been used in adults for several years. The question is whether IONM can be used in paediatric surgery for the identification and functional control of the RLN and the EBSLN, and what the advantages and disadvantages of using it are. METHODS: Surgical treatment of benign (n = 9) and malign (n = 2) thyroid diseases was carried out in eleven children (median age: 13 years) with a total of 18 nerves at risk (NAR). The function of the vocal cord was monitored in all children before and after surgery. Intraoperative identification and functional control of RLN and EBSLN was performed using the Neurosign 100. All results before and after resection of the thyroid gland were documented. RESULTS: A clear and reliable identification of the RLN and the EBSLN was possible in all cases. All NAR showed a constant physiological nerve signal before and after surgical resection of the thyroid gland. However, in one young patient the postoperative examination of the vocal cord revealed a partial paralysis on the left side after thyroidectomy, despite the constant intraoperative signal of the RLN. After a period of six months, normal functioning had resumed. CONCLUSION: The IONM of both RLN and EBSLN in adult surgery could be used successfully in paediatric surgery. In this study a clear and positive identification of both nerves was possible in all patients. Therefore the IONM of the RLN and EBSLN could develop into a successful and easy method for the prevention of intraoperative nerve damage during thyroid surgery in childhood and young adolescence. Assuming that a constant IONM signal represents a normal vocal cord, our evaluation showed that there is a small percentage of false negative and positive results.

[Not all vocal cord failure following thyroid surgery is recurrent paresis due to damage during operation. Statement of the German Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery concerning recurring paresis due to intubation]. / Nicht jeder Stimmlippenstillstand nach Schilddrüsenoperation ist eine chirurgischbedingte Rekurrensparese. Stellungnahme der "Interdisziplinären Studiengruppe Intraoperatives Neuromonitoring Schilddrüsenchirurgie" zur Problematik intubationsbedingter Rekurrensparesen.

Since the phoniatrician H. Bauer described the first case of recurrent laryngeal nerve palsy most likely caused by intubation some 45 years ago, several case reports have been published. However, systematic analyses regarding the frequency of recurrent laryngeal nerve palsies due to intubation are scarce, and none of them has used the proper methods to demonstrate clearly that such a mechanism exists. Currently available data justify the assumption that not every recurrent laryngeal nerve palsy following thyroid surgery is due to the operation itself and that the damage caused by intubation, however, may only account for a minority of these cases. The differential diagnosis of postoperative recurrent laryngeal nerve palsy requires the use of specific tools which go beyond simple laryngoscopy and include stroboscopy as well as intra- and extralaryngeal electromyography. A partial palsy of recurrent laryngeal nerve due to intubation would be associated with severe dysphonia or aphonia, not with dyspnea because of the typical intermediate position of the paralyzed vocal folds with a normal electromyographic function of the cricothyroid muscle. The use of these methods to identify the nature of postoperative recurrent laryngeal nerve palsy is recommended in cases of regular intraoperative neuromonitoring but postoperatively impaired function of the vocal cords.

[Effectiveness and results of intraoperative neuromonitoring in thyroid surgery. Statement of the Interdisciplinary Study Group on Intraoperative Neuromonitoring of Thyroid Surgery]. / Zuverlässigkeit und Konsequenzen des intraoperativen Neuromonitorings in der Schilddrüsenchirurgie. Stellungnahme der "Interdisziplinären Studiengruppe Intraoperatives Neuromonitoring Schilddrüsenchirurgie"

Intraoperative neuromonitoring (IONM) has yielded an increasing effect on thyroid surgery. During IONM, the recurrent laryngeal nerve is stimulated electrically and an acoustically transformed electromyographic signal is derived via either a needle electrode placed in the vocalis muscle or an electrode adjusted to the intubation tube. The IONM is used for identifying and predicting the function of the recurrent laryngeal nerve. Especially under difficult anatomic conditions, IONM has proven a valuable tool for identification of recurrent laryngeal nerves. This can lead to decreased occurrence of nerve palsy rates, as shown in numerous studies. The reliability of the IONM signal (defined as the correlation between intraoperative signal interpretation and postoperative vocal cord function) is reflected by a specificity as high as 98.2%, as shown by German multicenter studies. Thus, normal vocal cord function could be demonstrated postoperatively in over 98.2% of patients with intraoperatively unchanged neuromonitoring signals. If the neuromonitoring signal changed during operation, 39% of the patients suffered from transient vocal cord immobility and 12% had permanent loss of vocal cord function.

Immunogenicity of parathyroid allografts in the rat: immunosuppressive dosages effective in passenger leukocyte-rich small bowel transplants are not effective in parathyroid gland transplants with few passenger leukocytes.

BACKGROUND AND AIMS: The passenger leukocytes harboured within an allograft induce a massive allo-immune response that leads to allograft rejection if not countered by immunosuppression. We compared the response to short-term immunosuppression of parathyroid gland transplants possessing few passenger leukocytes with that of passenger leukocyte-rich small bowel transplants. METHODS: Heterotopic parathyroid and orthotopic small bowel transplantation was performed in a Wistar Furth-to-Lewis rat strain combination. Immunosuppression with cyclosporine A (CsA) was administered in different dosages for 14 days. Dysfunctional allografts were examined immunohistologically. RESULTS: CsA more effectively suppressed the immune response provoked by immunogenic small bowel grafts than that induced by less-immunogenic parathyroid grafts. Immunosuppression with 20 mg/kg per day induced long-term survival in the small bowel (165+/-21 days) but not in the parathyroid (28+/-3 days). All rejected grafts featured massive cellular infiltration by activated T cells as a sign of immune rejection. CONCLUSION: Immunosuppressive dosages effective in passenger leukocyte-rich small bowel transplants were not as effective in parathyroid gland transplants harbouring few passenger leukocytes. In spite of the paucity of passenger leukocytes in parathyroid grafts it is more difficult to control by immunosuppression the immune response to them than that to the passenger leukocyte-rich small bowel.

Combined surgical and antifungal treatment of a subcutaneous infection due to Paecilomyces lilacinus.

Paecilomyces lilacinus was the causal agent of a case of subcutaneous infection in a patient with liver cirrhosis. Surgical treatment in combination with systemic amphotericin B therapy led to complete recovery. Retrospectively performed microdilution testing revealed dose dependent in vitro susceptibility of the isolate to voriconazole (MIC = 2 g/ml) and terbinafine (MIC = 1 microg/ml).

[Does intraoperative nerve monitoring reduce the rate of recurrent nerve palsies during thyroid surgery?]. / Reduziert das intraoperative Neuromonitoring die Recurrenspareserate bei Schilddrüsenoperationen?

Two different aspects of the influence of neuromonitoring on the possible reduction of post-operative recurrent laryngeal nerve palsies require critical examination: the nerve identification and the monitoring of it's functions. Due to the additional information from the EMG signals, neuromonitoring is the best method for identifying the nerves as compared to visual identification alone. There are still no randomized studies available that compare the visual and electrophysiological recurrent laryngeal nerve detection in thyroid operations with respect to the postoperative nerve palsies. Nevertheless, comparisons with historical collectives show that a constant low nerve-palsy-rate was achieved with electrophysiological detection in comparison to visual detection. The rate of nerve identification is normally very high and amounts to 99 % in our own patients. The data obtained during the "Quality assurance of benign and malignant Goiter" study show that in hemithyreoidectomy and subtotal resection, lower nerve-palsy-rates are achieved with neuromonitoring as compared to solely visual detection. Following subtotal resection, this discrepancy becomes even statistically significant. While monitoring the nerve functions with the presently used neuromonitoring technique, it is possible to observe the EMG-signal remaining constant or decreasing in volume. Assuming that a constant neuromonitoring signal represents a normal vocal cord, our evaluation shows that there is a small percentage of false negative and positive results. Looking at the permanent recurrent nerve palsy rates, this method has a specificity of 98 %, a sensitivity of 100 %, a positive prognostic value of 10 %, and a negative prognostic value of 100 %. Although an altered neuromonitoring signal can be taken as a clear indication of eventual nerve damage, an absolutely reliable statement about the postoperative vocal cord function is presently not possible with intraoperative neuromonitoring.

[A Critical Estimation of Intraoperative Neuromonitoring (IONM) in Thyroid Surgery]. / Kritische Beurteilung und Fehlermöglichkeiten des intraoperativen Neuromonitoring (IONM) bei Operationen an der Schilddrüse.

We investigated 238 patients with 431 nerves at risk (NAR) undergoing thyroid surgery. Positive identification of the recurrent laryngeal nerve was obtained in 99.3 % of NAR with intraoperative neuromonitoring. 19 patients (4.4 % NAR) suffered from unilateral vocal cord dysfunction in the early postoperative phase. A complete restitution of vocal cord function could be demonstrated in 18 of these patients, leaving one patient (0.23 % NAR) with a permanent vocal cord dysfunction. Our data show that reliable predictions concerning the postoperative outcome of nerve function cannot always be made on the basis of the intraoperative findings. Thus, our own data show a specifity of 98.5 % and a negative predictive value of 96.8 %. On the other hand, sensitivity was 23.5 % and positive predictive value was 40 %. Misinterpretation of the intraoperative signal can lead to risky operative manoeuvres. Possible reasons for the misinterpretation of the intraoperative signal and a critical reflection on the possibilities and predictive values of neuromonitoring will be discussed.

[Identification and surgical anatomy of the external branch of the superior laryngeal nerve]. / Der Ramus externus des Nervus laryngeus superior (RELS): Ein Stiefkind in der Chirurgie der Schilddrüse.

Injury to the external branch of the superior laryngeal nerve (EBSLN) during thyroid surgery can cause serious consequences for patients who depend on control of pitch and a clear and forceful voice, like singers or professional speakers. We used the Neurosign 100(R) nerve monitor to identify 157 nerves in 108 patients undergoing thyroid surgery. The EBSLN was successfully identified in 98.7 % of cases. The recording electrode could be placed either into the cricothyroid muscle or the vocal cord. The latter position proved superior if the recurrent laryngeal nerve had to be identified as well. 16 percent of the nerves crossed the branches of the superior thyroid artery at or below the upper pole of the gland, posing a "high risk" for intraoperative lesions. Our data confirm the results of smaller studies reporting this type of nerve course in 12 % to 14 % of patients. The present findings show a significant number of EBSLN to be in danger of injury when the superior thyroid artery is ligated during thyroid surgery. Neuromonitoring proofed to be a reliable method to identify the nerve, which is an important element in concepts to prevent its injury.

[Patient selection criteria for single-sided or minimal invasive operative procedures in primary hyperparathyroidism (pHPT)]. / Kriterien für die Patientenauswahl zur einseitigen bzw. minimal-invasiven chirurgischen Therapie des primären Hyperparathyreoidismus (pHPT).

In 56 postoperative patients with primary hyperparathyroidism we analysed retrospectively whether a single-sided or minimal invasive operative procedure could have been utilized. Additionally the sensitivity of (99m)TC-Sestamibiscintiscanning and ultrasound of the neck region was assessed. Single gland disease was found in 49 patients, 6 patients had primary multiglandular disease and one patient revealed a double adenoma. The overall sensitivity of (99m)TC-Sestamibiscintiscanning and ultrasound was found to be 78 % and 53 % respectively. In 46 patients the operation would have been started minimal invasive, in 7 of these patients a conversion to bilateral exploration would have been necessary because of four gland hyperplasia, double adenoma or misleading preoperative localisation. In 39 patients a successful minimal invasive procedure would have been possible. A primary bilateral exploration would have been necessary in 10 patients because of either coexisting goiter or questionable localisation of the pathological altered gland. Since sensitivity of localisation diagnostics is low with regard to multiglandular disease, parathyroid hormone should be monitored intraoperatively whenever minimal invasive operative procedures are performed.

Surgical management of prosthetic vascular graft infection: comparative retrospective analysis of 30 consecutive cases.

BACKGROUND: Graft infection after vascular prosthetic reconstruction for the treatment of peripheral arterial occlusive disease (PAOD) is a rare but severe complication with poor outcome. The options for surgical treatment are not uniformly accepted and remain controversial. PATIENTS AND METHODS: We retrospectively analyzed the histories of 30 patients treated for prosthetic graft infection (Szilagyi grade III) in our hospital between 1994 and 1999 to determine which forms of treatment were best suited for which types of patient. In the majority of cases the initial treatment was lower-extremity bypass surgery. The most frequent location of infection was the groin (73%). Staphylococci (13% of which were methicillin resistant) were the most common type of bacteria. The overall incidence of prosthetic infection was 2.3%. RESULTS: After confirmation of the infection by computed tomography (CT) or white blood cell scintigraphy, one of the following 5 forms of surgical treatment was performed: 1. Removal of the infected prosthesis and its simultaneous replacement by an autologous vein bypass. 2. Bypass removal and secondary replacement by an autologous vein. 3. Extra-anatomical replacement. 4. Graft removal and primary amputation. 5. Local therapy with debridement and secondary wound healing. In some patients primary amputation after graft infection was necessary to prevent further deterioration with fulminant sepsis. The overall mortality was 17%, the amputation rate was 60%. CONCLUSIONS: The best results were achieved by early complete removal of the alloplastic material and one-step replacement by either an autologous vein or extra-anatomic bypass. This resulted in a limb salvage rate of 54% and 40% and mortality rates of 9% and 0%, respectively.

Influence of donor MHC class I antigen expression on graft survival after rat parathyroid allotransplantation.

BACKGROUND AND AIMS: We investigated the influence of donor MHC antigen expression on graft survival after parathyroid transplantation in three different strain combinations. METHODS: MHC class I and II expression on parathyroid tissue of Lewis (LEW), Dark Agouti (DA), and Wistar-Furth (WF) rats was first analysed semiquantitatively by immunohistochemistry. Additionally, five groups were transplanted: (1) LEW to LEW, (2) DA to DA, (3) LEW to DA, (4) WF to LEW, and (5) DA to LEW. METHODS: MHC class I expression was strong in DA, moderate in WF, and weak in LEW rats; MHC class II expression was negative in all three strains. In the interstitium of all investigated tissue specimens, the proportion of MHC class II-expressing cells was low. RESULTS: After syngeneic transplantation, graft survival could be documented over the whole observation period. A mean graft survival of 20 (+/-2) days was observed following transplantation from LEW to DA, grafts in the group WF to LEW were rejected after 13 (+/-1) days, and graft function lasted 8 (+/-2) days in the group DA to LEW. The number of intragraft leukocytes expressing MHC class II molecules was equal in all groups, whereas increased levels of MHC class I on rat parathyroid tissue before transplantation resulted in a more rapid rejection. CONCLUSION: These results demonstrate that immunogenicity of rat parathyroid tissue seems to be determined by the amount of MHC class I expressed on donor parenchymal cells.

Rat parathyroid allotransplantation: Influence of MHC antigen expression on graft survival.

MHC antigen expression in parathyroid tissue and its influence on graft survival after allogeneic transplantation were investigated using a heterotopic rat transplantation model. MHC class I and II expression in parathyroid tissue of Lewis (LEW), Dark Agouti (DA), and Wistar-Furth (WF) rats was analysed semi-quantitatively by using immunohistochemistry. MHC class I expression was strong in DA, moderate in WF, and weak in LEW rats parenchyma, whereas MHC class II expression was negative. In the interstitium of all investigated tissue specimens, the proportion of MHC class II-expressing cells was low. Additionally, four groups were transplanted: 1) LEW to LEW, 2) DA to DA, 3) LEW to DA, and 4) WF to LEW. After syngeneic transplantation, graft survival could be documented over the whole observation period. A median graft survival of 20 (+/-2) days was observed after transplantation from LEW to DA, whereas grafts in the group WF to LEW were rejected after 13 (+/-1) days. The number of intra-graft leucocytes expressing MHC class II molecules was the same in all groups, whereas increased levels of MHC class I in parathyroid tissue before transplantation resulted in a more rapid rejection. These results indicate that immunogenicity of rat parathyroid tissue might be determined by the amount of MHC class I expressed in donor parenchymal cells. Further experiments are necessary to validate this observation.

[Transplantation of porcine Langerhans islets for therapy of type I diabetes. The way to clinical application]. / Die Transplantation porciner Langerhans-Inseln zur Therapie des Typ-I-Diabetes. Der Weg zur klinischen Anwendung.

Transplantation of isolated pancreatic islets provides an interesting alternative to the present cure for diabetes: insulin injections and pumps. These are characterized by an insufficient glucose haemostasis and in the long run can induce kidney failure, blindness, heart failure, and amputations. Up to now more than 293 allogeneic islet transplantations have been performed in diabetics with chronical kidney failure. Despite some success, no real breakthrough has been yet achieved, though great efforts are being made to improve the various methodological steps on the way to clinical transplantation. The use of animal (xenogeneic) organs could be a solution to overcome the shortage of allogeneic donors. The current experimental and clinical research focuses on the use of pigs as organ donors, which have a number of advantages over the immunologically more compatible primates. This article reports on success and open questions concerning the efforts to isolate porcine islets for future clinical transplantation: the search for a suitable pig breed, the various isolation steps, purification and in vitro culture, transplantation models using-small and large animals, first clinical trials, and immunological reactions against the xenogeneic tissue. In addition, strategies to circumvent tissue rejection and future perspectives are discussed.

[Cellular immune reactivity in xenogenic "human-anti-pig" transplant combination]. / Zellvermittelte Immunreaktivität in der xenogenen Transplantationskombination "Mensch-anti-Schwein".

The worldwide lack of human organ donors puts the pig as potential xenogeneic donor species into the prime of interest. Aim of the present in vitro study is the analysis of T-cell activation in the clinically attractive combination "pig-to-human". Peripheral human blood leukocytes (hPBL) and peripheral porcine blood leukocytes (pPBL) were co-cultured for 4-8 days in the xenogeneic mixed lymphocyte reaction (xMLR) and cell proliferation was measured by 3H-thymidine uptake. Both cell populations were separated into T-cells and antigen presenting cells (APC) to analyze direct and indirect antigen recognition. The results show that (a) activation of human T-cells occurs, (b) the strength of activation depends e.g. on the human responder ("high" and "low" responders), (c) the strength of activation is independent of the responder's HLA-DR status, and (d) direct T-cell activation dominates over indirect activation. Thus, T-cell activation is another immunological barrier that has to be overcome before xenotransplantation can be clinically approached.