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PubMed2006

A program of microsurgical training for young medical students: are younger students better?

In the European countries there is a lack of young doctors. This shortage limits the possibilities for recruiting skilled surgeons for the microsurgical disciplines. Complicating the situation is the fact that most students do not decide on their area of specialization until the late clinical semesters. The authors present a new program of microsurgical training that dispenses completely with animal training. In addition, a scoring system is presented that enables instructors to compare the microsurgical skills of different students for the purpose of further statistical analysis. This scoring system could be used for the evaluation of potential microsurgical candidates as well as for other purposes, e.g. scientific projects. A total of 36 students with an average age of 24.2 were trained, with good-to-excellent results. Microsurgical training of young students can be recommended. A point worth exploring in the future is whether there are different learning curves for different age groups.

Adult↗

PubMed1995

Granulocyte-macrophage colony-stimulating factor as adjunct therapy in relapsed lymphoid malignancy: implications for economic analyses of phase III clinical trials.

With the increasing concern over the high cost of health care, policy makers have incorporated economic analyses into phase III clinical trials as the randomized clinical trials can provide important information on the efficacy and potential cost-effectiveness of new pharmaceutical agents. Economic analyses of single-hospital experience during phase III trials of granulocyte-macrophage colony-stimulating factor (GM-CSF) as adjunct therapy for high dose chemotherapy with autologous stem cell support found significant shortening of neutropenia with GM-CSF at each hospital, but shortened hospitalization (and lower costs) at only two of three hospitals. In this study, we added data from three additional hospitals and found that the 103 patients who received GM-CSF had, on average, 5.7 days shorter durations of severe neutropenia than the 95 patients who received placebo (p < 0.0001) and 3.4 days shorter in hospitalization (p = 0.06). However, the duration of hospitalization, the primary determinant of health care costs, was shorter for GM-CSF patients in only four of the six centers and the duration of hospitalization of placebo patients was shorter at the other two centers. Careful analyses must be carried out when phase III clinical trial results are used to derive estimates of cost-effectiveness of new pharmaceutical agents. The interpretation of economic analyses of phase III clinical trials raises issues related to the perspective of the investigators, study design, collection of data on resource utilization, learning curve effects and generalizability of the results to other settings.

Antineoplastic Agents↗

PubMed2005

A systematic review of the ultrasound estimation of fetal weight.

OBJECTIVES: The range and use of ultrasound fetal measurements have gradually been extended. Measurements have been combined to estimate fetal weight by mathematically based non-linear regression analysis or physically based volumetric methods. Fetal weight estimation is inaccurate, with poor sensitivity for prediction of fetal compromise. Several authors have shown the unacceptable level of intra- and interobserver variability in fetal measurement and the impact of errors on growth assessment. The aims of this study were to review the available methods and possible sources of inaccuracy. METHODS: Four databases were searched for studies comparing ultrasound estimated fetal weight (EFW) with birth weight. Studies meeting the inclusion criteria evaluated 11 different methods. Errors were graphically summarized. RESULTS: No consistently superior method has emerged. Volumetric methods provide some theoretical advantages. Random errors are large and must be reduced if clinical errors are to be avoided. CONCLUSIONS: The accuracy of EFW is compromised by large intra- and interobserver variability. Efforts must be made to minimize this variability if EFW is to be clinically useful. This may be achieved through averaging of multiple measurements, improvements in image quality, uniform calibration of equipment, careful design and refinement of measurement methods, acknowledgment that there is a long learning curve, and regular audit of measurement quality. Further work to improve the universal validity and accuracy of fetal weight estimation formulae is also required.

Birth Weight↗

PubMed2006

Factors affecting technical success of fetal aortic valve dilation.

OBJECTIVE: We have reported previously that valve dilation enhances growth of cardiac structures and may prevent hypoplastic left heart syndrome (HLHS) in fetuses with critical aortic stenosis. We aimed to investigate maternal/fetal factors which may affect the technical success of fetal valvuloplasty, and to describe perinatal complications of the procedure. METHODS: This was a descriptive series of 22 fetuses diagnosed with critical aortic stenosis developing into HLHS which underwent intervention by valvuloplasty. Initially this was attempted using a percutaneous approach; reassessment after our first five attempts, only one of which was successful, led to the introduction of the option of laparotomy. Technical success was defined as balloon inflation across the aortic annulus and a broader jet through the aortic valve as assessed by Doppler. Data collected included body mass index, demographic variables, ultrasound findings and postprocedure interventions. RESULTS: Technical success increased significantly if maternal laparotomy was an option (83.3% vs. 20.0%, P = 0.017). Laparotomy was performed in 66.6% (12/18) of cases. There was a learning curve that showed an increase in success rate and decrease in need for laparotomy over the 3-year study period. Neither the need for laparotomy nor the chances of technical success were predictable by gestational age, body mass index or placental location. Tocolysis was limited to perioperative prophylaxis; one woman experienced wound infection and fluid overload. Postoperatively, three fetuses died and two delivered prematurely, 2 and 7 weeks after intervention. CONCLUSION: Fetal aortic valvuloplasty can be performed with technical success, with low fetal loss rate and few maternal complications. While the need for laparotomy cannot be predicted, having it available as an option improves the technical success rate.

Adult↗

PubMed2006

The examiner's ultrasound experience has a significant impact on the detection rate of congenital heart defects at the second-trimester fetal examination.

OBJECTIVES: To determine whether training and experience in performing ultrasound examinations are factors that influence the prenatal detection of congenital heart defects (CHDs) in a non-selected population, in order to evaluate and improve the current training program. METHODS: All pregnant women who received a routine second-trimester ultrasound scan by a sonographer/midwife and delivered at our hospital between February 1991 and December 2001 were registered prospectively. Less experienced sonographer/midwives who had performed between 200 and 2000 routine examinations were compared with experienced sonographer/midwives who had carried out more than 2000 examinations. During the first 5 years of the study the heart structures obtained were registered in detail. RESULTS: Of 29,035 fetuses, 35/82 (43%) major CHDs were prenatally detected at the routine examination. The experienced sonographer/midwives obtained both the four-chamber view and the great arteries in 75%; the figure for the less experienced sonographer/midwives was 36% (P < 0.001). The differences in detecting major heart defects were 22/42 (52%) and 13/40 (32.5%), isolated CHDs 8/18 (44%) and 6/22 (27%) and CHDs with associated malformations 14/24 (58%) and 7/18 (39%), respectively. In both groups some CHDs with an abnormal four-chamber view were missed, although the experienced sonographer/midwives recognized significantly more of the abnormal views than did the less experienced sonographer/midwives (P = 0.002). CONCLUSIONS: Experience has a significant impact on the examination of the fetal heart and the prenatal detection rate of major CHDs. To avoid a relatively long learning curve, ultrasound education needs to intensify the teaching of the basic four-chamber view. The great arteries should be included after additional training. Those basic views of the fetal heart must be mastered before new views and advanced technology are added to the fetal heart examination.

Adult↗

PubMed2006

Rendering in fetal cardiac scanning: the intracardiac septa and the coronal atrioventricular valve planes.

OBJECTIVE: In this study we aimed to apply spatio-temporal image correlation (STIC) rendering to visualize the virtual planes of the interventricular and interatrial septa (IVS, IAS) as well as the atrioventricular (AV) annuli plane just distal to the semilunar valves (coronal atrioventricular (CAV) plane) in normal and pathological fetal hearts, to ascertain whether these planes add to fetal cardiac examination. METHODS: Unselected gravidae presenting for anatomy scan or patients referred for fetal echocardiography in the second and third trimesters of pregnancy with suspected or diagnosed cardiac malformation were scanned using the five planes technique with the STIC modality to obtain cardiac volume sets for each patient. Rendering capabilities were employed to obtain the 'virtual planes' to evaluate the IVS, IAS, AV annuli, and size and alignment of the great vessels. RESULTS: A total of 136 normal scans were performed to establish a learning curve for STIC acquisition and post-processing rendering and analysis. An additional 35 cases with cardiac anomalies were accrued. In 131/136 (96.3%) normal scans the IAS and IVS were visualized successfully, while in 127/136 (93.4%) normal fetuses the CAV plane was successfully visualized. In 13 anomalous cases the IVS plane improved ventricular septal defect (VSD) evaluation, and in four the IAS plane contributed to foramen ovale evaluation. The modality improved visualization of the septa and the assessment of the defects, as well as the foramen ovale flap and pattern of movement of the foramen ovale. In five cases the CAV plane improved evaluation of the alignment of the major vessels in relation to the AV annuli, and in three the evaluation of the semilunar valves, with or without malalignment of the great vessels. CONCLUSIONS: Rendering STIC technology allows the visualization of virtual planes (IAS, IVS, AV annuli-CAV plane), which can clarify our understanding of anatomical defects and may improve communication with the management team and family.

Adult↗

PubMed2004

Time domain measurement of blood flow in the human fetal aorta during normal pregnancy.

OBJECTIVE: To evaluate blood-volume flow-rate measurement in the fetal descending thoracic aorta using a non-invasive, non-Doppler, ultrasound technique. METHODS: This was a cross-sectional, observational study. Volume flow measurements were obtained from the descending thoracic aorta in 59 human fetuses between 20 and 40 weeks' gestation. These were uncomplicated pregnancies that resulted in the live births of appropriately grown infants. The measurements were obtained using a time domain processing technique: color velocity imaging quantification (CVI-Q). RESULTS: The blood-volume flow rate increased consistently from the second trimester until term. The mean values ranged between 100 mL/min at 20 weeks' gestation and approximately 350 mL/min at term. The normalized (weight-adjusted) volume flow rates decreased with increasing gestation, from a maximum of 626 mL/min/kg at 23 weeks to a minimum of 45.6 mL/min/kg at 37 weeks. CONCLUSIONS: The regular measurement of blood-volume flow in the descending fetal thoracic aorta is feasible using CVI-Q. Although there is a considerable learning curve, with adequate training there are potential clinical applications for this non-Doppler technique. However, limitations exist with the currently available technology for clinical use in fetal vascular studies.

Aorta, Thoracic↗

PubMed1997

Incidence of atypical glandular cells of uncertain significance in cervical cytology following introduction of the Bethesda System.

OBJECTIVE: To establish the frequency of the atypical glandular cells of uncertain significance (AGCUS) category, and its subcategories, as defined by the Bethesda System (TBS). METHODS: Our computerized records of cervical/vaginal cytology specimens submitted from January 1, 1993, through December 31, 1995, were retrospectively reviewed for specimens diagnosed as AGCUS. When appropriate, our subcategory of "AGCUS favor premalignant/malignant lesion" was further qualified as "favor endocervical adenocarcinoma in situ" or "suspicious for endometrial carcinoma." The number of specimens and patients diagnosed for each subcategory were grouped by calendar year. Differences in frequency between time periods were tested for statistical significance using chi 2 analysis. RESULTS: AGCUS was diagnosed in 1181 of 177,715 submitted specimens (0.66%). The frequency of subcategories was as follows: "favor reactive" (65%), "unable to further classify" (30%), "favor premalignant/malignant" (2.9%), "suspicious for endometrial carcinoma" (1.9%), and "favor endocervical adenocarcinoma in situ" (0.4%). From 1993 to 1995 there was an increase in the rate of diagnosis of AGCUS (0.55 to 0.73%; P < 0.001) and a decrease in the percentage of specimens with AGCUS subclassified as "favor premalignant/malignant" (6.2 to 0.5%; P < 0.001). Other subcategories showed no significant change in frequency over this time period. The rate of biopsy-proven preinvasive or invasive lesions in AGCUS patients also showed no significant change from year to year over this time period. CONCLUSION: The AGCUS diagnosis can be anticipated at a low but consistent rate from a cytology laboratory using TBS. Any comparison of laboratories should take into consideration the change in reporting frequencies that occurs as part of the "learning curve" following introduction of TBS reporting. Uniform diagnostic criteria and additional reports with large numbers of cytologic specimens will be needed to establish the expected frequency of AGCUS and its subcategories.

Adenocarcinoma↗

PubMed2000

Effect of surgeon's experience on the surgical outcome of laparoscopic surgery for women with endometrial cancer.

OBJECTIVE: The purpose of this study was to assess the effect of increasing surgeon's experience in the laparoscopic management of women with endometrial cancer on the surgical outcome of these patients. METHODS: Seventy-five consecutive women with clinical stage I endometrial cancer who underwent laparoscopically assisted vaginal hysterectomy, bilateral salpingo-oophorectomy, and pelvic lymph node sampling by the same surgeon using the same technique and instruments over a period of 2 years were divided into three equal groups based on the date of surgery. The three groups were compared in patient characteristics and surgical outcome using one-way analysis of variance and Pearson chi(2) tests. RESULTS: The three groups were similar in patient characteristics. There was no significant difference in estimated amount of blood loss, rate of conversion to laparotomy, complications, and length of hospital stay among the three groups. There was a significant decrease in operating time (means: 231.0 min for group 1, 175.0 min for group 2, and 167.7 min for group 3, P < 0.001) and a significant increase in the number of pelvic lymph nodes harvested (7.8 for group 1, 10.6 for group 2, and 11.9 for group 3, P < 0.05) with increasing surgeon's experience. CONCLUSIONS: A learning curve is demonstrated in the laparoscopic management of women with endometrial cancer. With increasing surgeon's experience, there is significant decrease in operating time and increase in the number of pelvic lymph nodes removed.

Aged↗

PubMed2004

Are there any complications with bioabsorbable fixation devices? A 10 year review in orthognathic surgery.

Bioabsorbable fixation devices have been used in our departments between November 1991 and November 2001 in orthognathic surgery. The aim of this retrospective study was to assess all complications experienced during this time period, when we have operated 163 patients who have undergone 329 orthognathic osteotomies fixated with bioresorbable devices. No postoperative intermaxillary fixation was used. Light guiding elastics were used for 5 to 7 weeks. Patients' acceptance was generally excellent and very few complications occurred during this follow-up of 10 years. The complications were minor and did not affect the end results of the operations. Minor complications occurred in 14 patients (8.6%). Only one patient (0.6%) had a postoperative infection with elevated infection parameters. The other minor complications consisted mainly of dehiscence of the wound and plate exposure together with granulation tissue in the operation field. The rest of the complications occurred in the beginning of our study, when large screw heads on top of the bone irritated the patient and had to be removed. Insufficient fixation resulted in open bite in three patients (1.8%) in the beginning of the trial use of new devices, which no longer are used. Based on our experience, bioresorbable devices are safe to be used in orthognathic procedures. However, there is a learning curve, as there is with all new methods introduced.

Absorbable Implants↗

PubMed2005

Paraspinal approach to the far lateral disc herniations: retrospective study on 42 cases.

Forty-two patients underwent surgery for far-lateral disc herniations. Average patient age was 45.1 years, 28 patients were male and 14 female. The level concerned most was L4-5 disc (55%). A paramedian muscle-splitting intertransverse approach is described for this type of disc herniation. This method allows direct visualization of the disc and root involved and does not provide bone resection and important surgical manipulation. Ninety-one percent of the patients reported excellent or good results according to Macnab outcome criteria with an average follow-up of 32.5 months (range 1-5 years). Twelve patients (28.6%) developed postoperative transient radicular pain that disappeared in 15-21 days after analgesic therapy. There were no recurrences or spinal instability. The paramedian muscle-splitting intertransverse approach is a rational technique. Its advantages are that the spine is not opened and spinal stability is maintained. It requires minimal soft-tissue and bone resection and the herniated disc is directly visualized. Moreover, it contains minimal manipulation of the neuro-vascular structures and avoids significant muscle retraction. However, it requires an adequate learning curve and good familiarity with microsurgical techniques.

Adult↗

PubMed2005

Urinary and sexual function after total mesorectal excision.

The autonomous pelvic nerves are in close contact to the visceral pelvic fascia that surrounds the mesorectum. The concept of total mesorectal excsion (TME) in rectal cancer treatment has led to a substantial improvement of autonomous pelvic nerve preservation. Consecutively, this highly precise and sharp dissection technique under direct vision reduces the problem of accidental bladder denervation from 50-60% with conventional rectal cancer surgery to less than 20% with TME and the problem of postoperative impotence from 70-100% to less than 30%. The learning curve in this technically demanding procedure plays a major role with regard to a satisfying nerve preservation. The laparoscopic approach for TME allows to obtain similarly favorable results with regard to postoperative urogenital function, at least for tumors situated in the middle and upper third of the rectum, compared with open surgery. The present paper describes and depictures in detail the anatomy and the pathophysiology of autonomic pelvic nerves, the surgical technique for nerve preservation and gives a short overview of the results in the literature including own data.

Autonomic Nervous System↗

PubMed2002

The role of immunosuppression in lymphoma.

Post-transplant lymphoproliferative disorder (PTLD) is a well-recognized yet serious complication in solid organ transplant recipients and currently represents the second most common de novo malignancy following solid organ transplantation. PTLD has been noted in all transplant immunosuppressive eras including the pre-cyclosporine, cyclosporine, and post-cyclosporine eras. The time from organ transplantation to PTLD presentation varies widely from less than 1 month to several years. PTLD presents with a broad spectrum of clinical manifestations depending on the transplanted organ, immunosuppressive therapy and patient age. Intense immunosuppressive therapy is a major risk factor for development of PTLD. Whenever a new agent is introduced, there is a learning curve that leads to dosing modifications, which in turn result in optimization of its immunosuppressive efficacy and reduction of toxicities, including PTLD. We review the major historical and recent immunosuppression trials to assess the impact of individual immunosuppressive agents and regimens on PTLD risk.

Humans↗

PubMed2001

Principles and problems of assessing the results of medical treatment.

The integration of clinical expertise with the best available evidence from systematic research is the foundation of evidence-based medicine (EBM). The results from a well-designed randomised controlled trial (RCT) is regarded as the best evidence on which to base treatment. In neurosurgical practice fewer treatments are based on the results of RCTs than in medical practice. The reasons are historical, ethical, practical and can be compounded by the surgical learning curve. In neurosurgical practice treatment protocols and surgical indications vary widely. In addition there is a lack of patient orientated, disease specific and generic outcome measures. However, it is a neurosurgical responsibility to provide hierarchical evidence upon which treatment can be based. Comparative audit may offer a solution provided there is high quality data collection, relevant measures of outcome, a defined case-mix and a representative population. Comparative audit can produce bias but neurosurgeons will need to meet the challenge of EBM. Their patients will expect it.

Evidence-Based Medicine↗

PubMed1984

Radial keratotomy: a comprehensive evaluation.

A prospective clinical investigation of radial keratotomy employing the Fyodorov method and instrumentation was initiated in March, 1980. The results of the first 147 eyes undergoing this surgical procedure for the reduction or elimination of myopia were analyzed one year following surgery. The mean preoperative, uncorrected visual acuity was finger counting vision and the mean preoperative myopic spherical equivalent was 5.33 diopters. The preoperative myopic refractive error ranged from 1.75 to 11.75 diopters. Radial keratotomy resulted in a mean uncorrected visual acuity of 20/35 with a mean reduction on myopia of 4.66 diopters. Eighty percent of the 147 eyes experienced 20/40 or better uncorrected vision. Sixty-eight percent of high myopia eyes (6.00 to 11.75 D) attained this level of uncorrected vision with a mean reduction of myopia of 6.23 diopters. Glare and variation of vision were the most frequently reported complications. A non-progressive endothelial cell loss of 5.2 percent was observed. The degree of preexisting myopia, patient age, fellow eye experience and surgeon learning curve significantly influenced the surgical result and facilitated the predictability of the procedure. Incision depth was directly related to surgical result. The low myopia group achieved stabilization of effect by six months while stabilization occurred later in patients with high degrees of initial myopia. Patient satisfaction was high and 78 per cent of the patients elected to undergo radial keratotomy in their fellow eye.

Adolescent↗

PubMed1995

TULIP: transurethral ultrasound-guided laser-induced prostatectomy.

Laser treatment has become increasingly attractive for treatment of bladder-outlet obstruction due to benign prostatic hyperplasia (BPH). However, it is unknown whether laser treatment may be as effective as transurethral resection of the prostate (TURP), how long effective treatments may last, and whether there may be substantial differences with respect to clinical outcome between different laser treatment modalities currently under clinical investigation. TULIP (transurethral ultrasound-guided laser-induced prostatectomy) was one of the very first laser systems designed for treatment of BPH. The procedure is performed exclusively under transurethral ultrasound guidance, with which the surgeon has to become familiar. However, data reported from single-institution as well as multicenter studies demonstrate that the technique has only a small learning curve. The majority of patients treated by TULIP will experience substantial improvements in subjective and/or objective symptoms, which nevertheless do not appear to be as good as those seen after TURP. This is also shown by data from a prospective and randomized TULIP versus TURP study. However, it has to be emphasized that the clinical significance of such differences remains unknown. Advantageous for TULIP (which may be performed under analgosedation) are reduced blood loss, hospitalization, and rate of postoperative sexual dysfunction. Disadvantageous (as compared with TURP) are the delayed onset of success combined with the prolonged catheterization time and irritative symptoms in the early postoperative phase. In addition, as no tissue is obtained for histology examination, incidental prostate cancer may be missed.

Humans↗

PubMed1994

Preliminary experience with intracorporeal laparoscopic ultrasonography using a sector scanning probe. A prospective comparison with intraoperative cholangiography in the detection of choledocholithiasis.

Laparoscopic ultrasonography is a novel technique which may be useful in screening for choledocholithiasis during laparoscopic cholecystectomy. Following concerns regarding the "learning curve" and accuracy associated with the adoption of this user-dependent technology, we have prospectively evaluated a commercially available 90 degrees sector scanning laparoscopic ultrasound probe during elective laparoscopic cholecystectomy. Laparoscopic ultrasonography was performed in 60 patients and identified common duct stones in nine patients (one "false positive" and "one false negative"), and previously unsuspected duct stones were defined in three out of four patients. The gallbladder and portal vein were constantly defined anatomical landmarks throughout the study, whereas the suprapancreatic bile duct, intrapancreatic bile duct, and pancreatic duct were identified in 100%, 80%, and 85% of patients in the third consecutive group of 20 patients examined. Laparoscopic ultrasonography has the potential to accurately identify common duct stones during laparoscopic cholecystectomy and thereby implement a policy of "superselective" operative cholangiography. However, adequate training for surgeons unfamiliar with this technology is recommended.

Cholangiography↗

PubMed1995

Evolving techniques in endoscopic extraperitoneal herniorrhaphy.

Endoscopic extraperitoneal herniorrhaphy (EEPH) was utilized to repair 326 groin hernias in 249 patients over a 32-month period. Nearly one in ten of the repairs was for a recurrent hernia. Several patients had contralateral hernias diagnosed only at the time of endoscopic examination. A recurrence rate of 1.6% and an overall complication rate of 5.2% are cited. After a plateau was reached on the surgeon's learning curve, various modifications in technique were implemented. Through these modifications, EEPH has become a safe, efficient, and standardized operation that can be performed with decreasing costs to the hospital and with increasing advantages to the patient.

Adolescent↗