Point-of-care ultrasound for the diagnosis of an atypical small bowel obstruction in a cannabis user: a case report

This case report describes an atypical small bowel obstruction in a 71- years old cannabis user and how point-of-care of ultrasound (PoCUS) helped to its management by further orientating the physician toward the bowel obstruction etiology, namely intussusception. Intussusception is the invagination of an intestinal segment into the adjacent segment. The acute clinical presentation of intussusception often has non-specific symptoms, and the diagnosis can be challenging. While the most common etiology is neoplasm, intussusception also occurs in bowel motility disorder such as after cannabis use. Although this case report illustrates intussusception PoCUS findings, these should nevertheless be integrated into the clinical picture and CT-scan should remain the gold standard complementary examination in case of a suspected bowel obstruction.

Distalization of Standard Roux-en-Y Gastric Bypass: Indications, Technique, and Long-Term Results

INTRODUCTION

Weight loss failure or weight regain after primary Roux-en-Y gastric bypass (RYGB) is a challenge for bariatric surgeons. Failure to achieve a body mass index (BMI) <35 kg/m2 after RYGB occurs in up to 40.0%. The aim of this study was to evaluate long-term results of a novel technique for distalization of Roux-en-Y gastric bypass (DRYGB) as a revisional procedure.

METHODS

Retrospective data were reviewed for 22 patients who had undergone RYGB and failed to achieve an excess weight loss (EWL) >50% or BMI <35 kg/m2 and underwent limb distalization between 2013 and 2022. For this DRYGB procedure, the length of the common channel was 100 cm, and the lengths of the biliopancreatic limb and the alimentary limb were 1/3 and 2/3 of the remaining bowel, respectively.

RESULTS

The mean BMI values before and after DRYGB were 43.7 kg/m2 and 33.5 kg/m2, respectively. Five years after DRYGB, mean % EWL was 74.3% and mean % total weight loss (TWL) was 28.8%. Mean % EWL and mean % TWL of the two procedures (RYGB and DRYGB) after 5 years were 80.9% and 44.7%, respectively. Three patients experienced protein calorie malnutrition. One was reproximalized and the others were treated with parenteral nutrition with no recurrence. There was a significant decrease in the incidence of diabetes type 2 and dyslipidemia after DRYGB.

CONCLUSION

The DRYGB procedure results in substantial and sustained long-term weight loss. Due to the risk of malnutrition, patients must be strictly followed for life after the procedure.

Markers of vitamin D metabolism and premenstrual symptoms in healthy women with regular cycles

STUDY QUESTION

Are insufficient 25-hydroxyvitamin D (25(OH)D) concentrations, and other markers of vitamin D metabolism, associated with premenstrual symptoms in healthy women with regular menstrual cycles?

SUMMARY ANSWER

25(OH)D insufficiency was associated with specific physical premenstrual symptoms, while no associations were observed with psychological symptoms or with other markers of vitamin D metabolism.

WHAT IS KNOWN ALREADY

Prior studies evaluating vitamin D and premenstrual symptoms have yielded mixed results, and it is unknown whether 25(OH)D insufficiency and other markers of vitamin D metabolism are associated with premenstrual symptoms.

STUDY DESIGN, SIZE, DURATION

We used two cohorts of women with regular menstrual cycles; 1191 women aged 18-40 years in EAGeR (cross-sectional analysis of a prospective cohort within a randomized trial) and 76 women aged 18-44 years in BioCycle (prospective cohort). In EAGeR, premenstrual symptoms over the previous year were assessed at baseline, whereas in BioCycle, symptoms were assessed prospectively at multiple points over two menstrual cycles with symptoms queried over the previous week. In both cohorts, symptomatology was assessed via questionnaire regarding presence and severity of 14 physical and psychological symptoms the week before and after menses. Both studies measured 25(OH)D in serum. We also evaluated the association of additional markers of vitamin D metabolism and calcium homeostasis, including intact parathyroid hormone (iPTH), calcium (Ca), fibroblast growth factor 23 (FGF23), and 1,25 dihydroxyvitamin D (1,25(OH)2D) with premenstrual symptoms in the BioCycle cohort.

PARTICIPANTS/MATERIALS, SETTING, METHODS

One cohort of women actively seeking pregnancy (Effects of Aspirin in Gestation and Reproduction (EAGeR)) and one cohort not seeking pregnancy (BioCycle) were evaluated. Log-binomial regression was used to estimate risk ratios (RR) and 95% CIs for associations between insufficient 25(OH)D (<30 ng/ml) and individual premenstrual symptoms, adjusting for age, BMI, race, smoking, income, physical activity, and season of blood draw.

MAIN RESULTS AND THE ROLE OF CHANCE

25(OH)D insufficiency was associated with increased risk of breast fullness/tenderness (EAGeR RR 1.27, 95% CI 1.03, 1.55; BioCycle RR 1.37, 95% CI 0.56, 3.32) and generalized aches and pains (EAGeR RR 1.33, 95% CI 1.01, 1.78; BioCycle 1.36, 95% CI 0.41, 4.45), though results were imprecise in the BioCycle study. No associations were observed between insufficient 25(OH)D and psychological symptoms in either cohort. In BioCycle, iPTH, Ca, FGF23, and 1,25(OH) 2D were not associated with any premenstrual symptoms.

LIMITATIONS, REASONS FOR CAUTION

Results from the EAGeR study were limited by the study design, which assessed both 25(OH)D at baseline and individual premenstrual symptoms over the past year at the baseline. As such, reverse causality is a potential concern. Though premenstrual symptoms were assessed prospectively in the BioCycle cohort, the power was limited due to small sample size. However, results were fairly consistent across both studies.

WIDER IMPLICATIONS OF THE FINDINGS

Serum 25(OH)D may be associated with risk and severity of specific physical premenstrual symptoms.

STUDY FUNDING/COMPETING INTEREST(S)

This work was supported by the Intramural Research Program of the Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland (Contract nos. HHSN267200603423, HHSN267200603424, and HHSN267200603426). JG.R. and D.L.K. have been funded by the NIH Medical Research Scholars Program, a public-private partnership jointly supported by the NIH and generous contributions to the Foundation for the NIH by the Doris Duke Charitable Foundation (Grant #2014194), the American Association for Dental Research, the Colgate Palmolive Company, Genentech, and other private donors. For a complete list, visit the foundation website at http://www.fnih.org. The authors have no conflicts of interest to disclose.

TRIAL REGISTRATION NUMBER

Clinicaltrials.gov NCT00467363.

Thromboembolic risk stratification by TRiP(cast) score to rationalise thromboprophylaxis in patients with lower leg trauma requiring immobilisation: a study protocol of the casting stepped-wedge cluster randomised trial

INTRODUCTION

Patients with lower limb trauma requiring orthopaedic immobilisation may be at risk of venous thromboembolism but opinions differ about who may benefit from thromboprophylactic anticoagulant treatment.The aim of this CASTING study is to demonstrate the safety of thromboprophylaxis based on the Thrombosis Risk Prediction for patients with cast immobilisation (TRiP(cast) score with regards to the 3-month incidence of symptomatic venous thromboembolism events in low-risk patients not receiving thromboprophylaxis, as well as the usefulness of this strategy on the rate of patients receiving anticoagulant treatment in comparison to current practice.

METHODS AND ANALYSIS

CASTING will be a stepped-wedge cluster randomised controlled clinical trial, performed in 15 emergency departments in France and Belgium. With their informed consent, outpatients admitted to one of the participating emergency departments for a lower limb trauma requiring orthopaedic immobilisation without surgery will be included. All centres will begin the trial with the 'observational period' and, every 2 weeks, 1 centre will be randomly assigned to switch to the 'interventional period' and to apply the TRiP(cast) score, in which only patients with a score ≥7 will receive thromboprophylactic anticoagulant treatment. The primary endpoint is the rate of clinical thromboembolic events within 90 days following the inclusion of low-risk patients not receiving thromboprophylaxis.

ETHICS AND DISSEMINATION

The protocol has been approved by the Comité de Protection des Personnes Sud I (Ethics Review ID-RCB: 2019-A01829-48) for France and the Comité d'éthique hôpital-facultaire Saint Luc (N° B403201941338) for Belgium. It is carried out in accordance with the Declaration of Helsinki and Good Clinical Practice guidelines. The findings of this study will be disseminated in peer-reviewed journals and at scientific conferences.

TRIAL REGISTRATION NUMBER

NCT04064489.

Teaching humanitarian surgery: Filling the gap between NGO needs and subspecialized surgery through a novel inter-university certificate

Background: Access to surgical care is a global health burden. A broad spectrum of surgical competences is required in the humanitarian context whereas current occidental surgical training is oriented towards subspecialties. We proposed to design a course addressing the specificities of surgery in the humanitarian setting and austere environment.Method: The novelty of the course lies in the implication of academic medical doctors alongside with surgeons working for humanitarian non-governmental organizations (NGO). The medical component of the National Defense participated regarding particular topics of war surgery. The course is aimed at trained surgeons and senior residents interested in participating to humanitarian missions.Results: The program includes theoretical teaching on surgical knowledge and skills applied to the austere context. The course also covers non-medical aspects of humanitarian action such as international humanitarian law, logistics, disaster management and psychological support. It comprises a large-scale mass casualty exercise and a practical skills lab on surgical techniques, ultrasonography and resuscitation. Attendance to the four teaching modules, ATLS certification and succeeding final examinations provide an interuniversity certificate.30 participants originating from 11 different countries joined the course. Various surgical backgrounds, training levels as well as humanitarian experience were represented.Feedback from the participants was solicited after each teaching module and remarks were applied to the following session. Overall participant evaluations of the first course session are presented.Conclusion: Teaching humanitarian surgery joining academic and field actors seems to allow filling the gap between high-income country surgical practice and the needs of the humanitarian context.

Impact of a prehospital discrimination between trauma patients with or without early acute coagulopathy of trauma and the need for damage control resuscitation: rationale and design of a multicenter randomized phase II trial

BACKGROUND

The evidence of the Trauma Induced Coagulopathy Clinical Score (TICCS) accuracy has been evaluated in several studies but the potential effect of its use on patient outcomes needs to be evaluated. The primary objective of this study is to evaluate the impact on mortality of a prehospital discrimination between trauma patients with or without a potential need for damage control resuscitation.

METHODS

The trial will be designed as randomized phase II clinical trial with comparison of the experimental protocol against the standard of care. The TICCS will be calculated on the site of injury for the patients of the intervention group and treatment will be guided by the TICCS value. Seven days mortality, 30 days mortality, global use of blood products and global hospital length-of-stay will be compared.

DISCUSSION

Many data suggest that a very early flagging of trauma patients in need for DCR would be beneficial but this need to be proved. Do we improve our quality of care by an earlier diagnosis? Does a prehospital discrimination between trauma patients with or without a potential need for DCR has a positive impact?

Roux-En-Y Fistulojejunostomy: a New Therapeutic Option for Complicated Post-Sleeve Gastric Fistulas, Video-Report

BACKGROUND

Laparoscopic sleeve gastrectomy (LSG) has become during the last few years the most frequent procedure in bariatric surgery. However, complications related to the gastric staple line can be even more serious. The incidence of gastric fistula after LSG varies from 1 to 7%. Its management can be very challenging and long. In case of chronic fistula and failure of the previous treatment, total gastrectomy or Roux-en-Y fistulo-jejunostomy (RYFJ) might be considered. RYFJ has been described very rarely as a salvage procedure of gastric leaks after LSG.

METHODS

Between January 2015 and December 2015, we have performed a RYFJ in two patients, with chronic and persisting gastric fistulas, one after LSG and one after duodenal switch, respectively. In the two patients, the RYFJ procedure was attempted laparoscopically but in one case (patient after duodenal switch), conversion into laparotomy was necessary because of severe intra-abdominal inflammatory adhesions. In our video, we are presenting the case of this particular patient treated laparoscopically with a late and persisting leak 1 year after LSG.

RESULTS

In this multimedia high-definition video, we described the steps of our technique of laparoscopic RYFJ. There was neither mortality nor severe postoperative complications. The fistula control after a minimum of 6 months follow-up was 100% for both of patients.

CONCLUSIONS

RYFJ in our particular case was efficient. However, larger series and longer follow-up are needed to confirm the efficiency of the RYFJ as a salvage procedure.

Assessing particle kinematics via template matching algorithms

Template matching algorithms represent a viable tool to locate particles in optical images. A crucial factor of the performance of these methods is the choice of the similarity measure. Recently, it was shown in [Gao and Helgeson, Opt. Express 22 (2014)] that the correlation coefficient (CC) leads to good results. Here, we introduce the mutual information (MI) as a nonlinear similarity measure and compare the performance of the MI and the CC for different noise scenarios. It turns out that the mutual information leads to superior results in the case of signal dependent noise. We propose a novel approach to estimate the velocity of particles which is applicable in imaging scenarios where the particles appear elongated due to their movement. By designing a bank of anisotropic templates supposed to fit the elongation of the particles we are able to reliably estimate their velocity and direction of motion out of a single image.

Impact of lymphocyte and monocyte recovery on the outcomes of allogeneic hematopoietic SCT with fludarabine and melphalan conditioning

We have recently shown that lymphocyte and monocyte recovery by day +100 are associated with survival post myeloablative allogeneic hematopoietic transplant for acute leukemia. We hypothesized that lymphocyte and monocyte recovery would have a similar impact on survival in the reduced intensity setting. To test this hypothesis, we analyzed clinical data from 118 consecutive fludarabine/melphalan-conditioned patients by correlating peripheral blood absolute lymphocyte counts and monocyte counts (ALC and AMC, respectively) at days +15, +30, +60 and +100 with the outcomes. Multivariate analysis revealed that day +100 AMC (risk ratio (RR) 0.22, 95% confidence interval (CI) 0.07-0.73, P=0.01) and mild chronic GVHD (RR 0.09, 95% CI 0.005-0.43, P=0.008) were independently associated with survival. To explore whether the patterns of lymphocyte and monocyte recovery had a prognostic value, we performed unsupervised hierarchical clustering on the studied hematopoietic parameters and identified three patient clusters, A-C. Patient clusters A and B both had improved OS compared with cluster C (77.8 months vs not reached vs 22.3 months, respectively, P<0.001). No patient in cluster C had a day +100 AMC >300. Both severe acute GVHD and relapse occurred more frequently in cluster C. Our data suggest that patients with low AMC by day +100 post fludarabine/melphalan-conditioned allogeneic hematopoietic SCT may be at risk for poor outcomes.

Mondor disease: a case report in ED

Mondor disease is a form of superficial thrombophlebitis affecting the subcutaneous veins, specifically of the anterolateral thoracoabdominal wall. Clinical presentation is commonly a subcutaneous, tender, painful cordlike induration, usually founded in the breast or axilla. It affects typically middle-aged women. A 36-year-old patient was admitted to the emergency department to a chest discomfort and to discovery of a palpable, nonerythematous, and painful cordlike structure running from the inferior pole of her left breast to the left iliac pit. She had no history of trauma, injury, or intensive physical activity. Ultrasonography confirmed thrombosis of the thoracoepigastric vein. A thrombophilic workup performed 2 years ago was normal. The patient was treated by enoxaparin 1 mg/kg per day for 30 days. Evolution was favorable. The etiology of Mondor disease remains unclear. Predisposing factors are mainly trauma, excessive physical activity, surgery, infections. Ultrasonography is used to confirm the diagnosis. Coagulation tests should be performed to exclude hypercoagulability condition. In the past, symptomatic approach with anti-inflammatory drugs was proposed. Recent guidelines suggest prophylactic or intermediate doses of low-molecular-weight heparin for at least 4 weeks. Although uncommon, Mondor disease has to be recognized to avoid useless diagnosis testing and to deliver a specific treatment.

The suturing concept for laparoscopic mesh fixation in ventral and incisional hernia repair: Mid-term analysis of 400 cases

BACKGROUND

The authors describe a minimally invasive treatment of moderate to large incisional and ventral hernia defects using Parietex composite mesh.

METHODS

All defects are closed laparoscopically or through a minilaparotomy using sutures, and the composite mesh is fixed intraperitonally using transabdominal fixation with nonabsorbable sutures to avoid the use of staple or tack fixation, which has been associated with various complications, including major loop adhesion and mesh migration. The midterm results for 400 patients are presented in terms of efficacy and safety.

RESULTS

During a mean follow-up period of 28 months for 80% of the patients, the median operating time was 74 min and the median hospital stay was 3 days. There were eight seromas (2%), all on large defects. Transient pain was experienced by 10 patients (2.5%), and resolved over time with analgesic treatment. There was one early case of sepsis (0.25%), attributable to secondary breakdown of the bowel wall in a case of recurrent incisional hernia, which led to removal of the mesh. Residual chronic parietal pain was reported for 10 patients (2.5%), 2 of whom were released after excision of neuroma; 3 trocar-site herniations (0.75%); and lipoma formation on the site of the hernia sac in 6 cases (1.5%).

CONCLUSION

Laparoscopic ventral hernia treatment using Parietex composite mesh is an effective and safe procedure. Morbidity and recurrence rates are low, and the 2-year outcomes are promising, with no prosthesis migration or complication related to intraperitoneal positioning of the mesh.

Foley catheter balloon tamponade for life-threatening hemorrhage in penetrating neck trauma

BACKGROUND

Foley catheter (FC) balloon tamponade is a well-recognized technique employed to arrest hemorrhage from penetrating wounds. The aim of this study was to review our experience with this technique in penetrating neck wounds and to propose a management algorithm for patients with successful FC tamponade.

METHODS

A retrospective chart review (July 2004-June 2005 inclusive) was performed of patients identified from a prospectively collected penetrating neck injury computer database in whom FC balloon tamponade was used. The units' policy for penetrating neck injuries is one of selective nonoperative management. All patients with successful FC tamponade underwent angiography. A venous injury was diagnosed if angiography was normal. Ancillary tests were performed as indicated. Removal of the FC was performed in the OR.

RESULTS

During the study period, 220 patients with penetrating neck injuries were admitted to our unit. Foley catheter balloon tamponade was used in 18 patients and was successful in 17 patients. Angiography was positive in 3 patients, all of whom underwent surgery. The FC was successfully removed in 13 patients at a mean of 72 (range 48-96) hours. One patient bled after removal of the catheter, mandating emergency surgery.

CONCLUSION

Foley catheter balloon tamponade remains a useful adjunct in the management of selective patients with penetrating, bleeding neck wounds.

Left paraduodenal hernia: a case report

Congenital internal hernias often remain unrecognized since they are infrequent and produce nonspecific abdominal symptoms. Abdominal imaging during a symptomatic episode leads to the diagnosis. Surgical treatment is essential regarding the risks of incarceration. We report a case of left paraduodenal hernia misdiagnosed for over thirty years despite extensive imaging and surgical exploration.

Radio-chemotherapy as a preoperative treatment for advanced rectal cancer. Evaluation of down-staging and morbidity

BACKGROUND

The standard therapy for patients with clinically resectable rectal cancer is generally considered to be surgery. If the patient is diagnosed with advanced disease, postoperative radio-chemotherapy (RCT) is usually recommended. In our study we aimed to investigate and analyze the effectiveness and toxicity of preoperative pelvic radiotherapy in combination with 5-fluorouracil (5-FU) in locally advanced rectal cancer.

PATIENTS AND METHODS

From June 1999 to September 2001 we evaluated 50 consecutive patients [37 male and 13 female; average age 65.1 (range 46-79.5) years] with locally advanced rectal carcinoma. 32 patients were staged as uT3, 14 as uT4, and 4 as uT2. Regarding N-staging, 22 patients were diagnosed as uN0. 2 patients had distant metastases, with liver metastases in both instances. Conformal irradiation was performed with a box technique (4-field technique) with a dose of 45 Gy (5 x 1.8 Gy per week for a total of 25 sessions). From days 1-5 and 29-33, all patients received 5-FU (500 mg/m(2 ) per day, as a continuous i.v. injection).

RESULTS

Remission was observed in 28 patients (56%), with down-staging of at least one T-stage. A better success rate was achieved for patients with deep-seated tumors (64% of the patients in this group). Complete remission was observed in 4 patients (8.0%) and progression in 3 (6.0%). 15 patients had no detectable change in tumor staging (30.0%). A surgical R0 resection could be achieved in 43 patients, an R1 resection (minimal margin) in 7. Side effects and toxicity (common toxicity criteria) of RCT included grade I-II dysuria in 5 patients (10%), grade I-II diarrhea in 20 patients (40%), and severe diarrhea in 2 patients (4.0%). Grade I-II skin reaction was noticed in 22 patients (44.0%), severe skin reaction only in 1 patient. Regarding acute postoperative morbidity, abscess and fistula formation was noted in 8 patients (16.0%), with anastomosis leakage in 7 (14%).

CONCLUSION

Preoperative radiotherapy appears to be a feasible therapeutic approach with moderate toxicity and the potential to induce down-staging. The data presented in this study confirm the preliminary reports on this neoadjuvant treatment.

[Early results of a prospective study in patients with computer-assisted femur shaft preparation in total hip endoprosthesis implantation (Robodoc system)--indications, outcome, complications]

AIM

Indications, results, advantages and disadvantages of the computer-guided femoral preparation in total hip arthroplasty (Robodoc) in our patients are recorded and represented.

METHOD

41 patients who underwent a computer-guided femoral preparation in total hip arthroplasty (Robodoc) were examined after 1 year on average in a prospective study. The evaluation was made using the Harris Hip Score. The advantages and disadvantages of the Robodoc-assisted surgery are described.

RESULTS

More than 80% of the patients had a good or very good result (> 80 points of Harris Hip Score) 3 month after surgery; after 6 months in 20 of 21 patients a score of more than 85 pts. was calculated. The following complications were noticed: thrombotic embolism (2) with one lethal embolism included, fracture of the greater trochanter using the straight stem (3), aseptic drainage due to hematoma (2). 12 patients noticed a postoperative pain at the distal marking pin location (condylus femoris medialis) for an average of 3 months.

CONCLUSION

Generally, Robodoc-assisted surgery may be performed in all uncemented total hip arthroplasties. The individual indication should be checked because of the increased effort of surgery, the advantages and disadvantages, and the non-proven better long-term results in comparison to the regular technique. It seems that the Robodoc system provides advantages in post-traumatic arthritis and deformities of the proximal femur (varus and valgus neck) on account of the computer-aided preoperative planning and correct operative realization.

First Results from Viper: Detection of Small-scale Anisotropy at 40 GHz

Results of a search for small-scale anisotropy in the cosmic microwave background (CMB) are presented. Observations were made at the South Pole using the Viper telescope, with a 0&fdg;26 (FWHM) beam and a passband centered at 40 GHz. Anisotropy band-power measurements in bands spanning the range of l in which the first acoustic peak is expected (bands centered at l=108, 173, 237, 263, 422, and 589) are reported. Statistically significant CMB anisotropy is detected in all bands.

Thrombin and mast cell tryptase regulate guinea-pig myenteric neurons through proteinase-activated receptors-1 and -2

1. Proteases regulate cells by cleaving proteinase-activated receptors (PARs). Thrombin and trypsin cleave PAR-1 and PAR-2 on neurons and astrocytes of the brain to regulate morphology, growth and survival. We hypothesized that thrombin and mast cell tryptase, which are generated and released during trauma and inflammation, regulate enteric neurons by cleaving PAR-1 and PAR-2. 2. We detected immunoreactive PAR-1 and PAR-2 in > 60 % of neurons from the myenteric plexus of guinea-pig small intestine in primary culture. A large proportion of neurons that expressed substance P, vasoactive intestinal peptide or nitric oxide synthase also expressed PAR-1 and PAR-2. We confirmed expression of PAR-1 and PAR-2 in the myenteric plexus by RT-PCR using primers based on sequences of cloned guinea-pig receptors. 3. Thrombin, trypsin, tryptase, a filtrate from degranulated mast cells, and peptides corresponding to the tethered ligand domains of PAR-1 and PAR-2 increased [Ca2+]i in > 50 % of cultured myenteric neurons. Approximately 60 % of neurons that responded to PAR-1 agonists responded to PAR-2 agonists, and > 90 % of PAR-1 and PAR-2 responsive neurons responded to ATP. 4. These results indicate that a large proportion of myenteric neurons that express excitatory and inhibitory neurotransmitters and purinoceptors also express PAR-1 and PAR-2. Thrombin and tryptase may excite myenteric neurons during trauma and inflammation when prothrombin is activated and mast cells degranulate. This novel action of serine proteases probably contributes to abnormal neurotransmission and motility in the inflamed intestine.

Oxygen, pH value, and carbon source induced changes of the mode of oscillation in synchronous continuous culture of Saccharomyces cerevisiae

Oscillations of measured process parameters occur in continuous cultures of Saccharomyces cerevisiae owing to a partial synchronization of budding. Intentional changes of the oxygen concentration, pH value, and carbon source cause effects on the period length similar to those known from variations of the dilution rate. The generation times of parent and daughter cells frequently differ in synchronous culture. To analyze the oscillation the term mode IJ of oscillation is used, which is defined as the ratio IJ of the generation times of parent and daughter cells. When the dissolved oxygen concentration was reduced to zero, the mode of oscillation changed within two periods from mode 12 to mode 11, caused by a decrease of the generation time of daughter cells and an increase of that of the parent cells. When the pH value was slowly reduced from 5.0 to 3.9, a change from mode 112 to mode 13 was observed. Mode 13, representing one parent and three daughter cell populations (the start of budding of each of the three being delayed by one period), denotes an elongated generation time of the daughter cells compared to mode 112, marked by one parent and two different daughter cell classes. When the carbon source galactose was replaced by glucose a mode change from mode 12 to mode 11 was observed. This alteration of the mode was found to be dependent on the status of the cell cycle at the time when the carbon source is changed. The population distribution in batch cultures with glucose or galactose as a substrate was analysed by dyeing the DNA and counting the bud scars. Galactose provoked higher growth rates for the older cells. According to the model for stationary synchronous growth parameters like DO, pH value or the type of carbon source can be varied within a certain range without effecting the period length. If the variation imposes a certain stress, the culture switches to a new mode. These kinds of parameters therefore provide selective measures to influence the period lengths and the modes of oscillation.

Coagulative interstitial laser-induced thermotherapy of benign prostatic hyperplasia: online imaging with a T2-weighted fast spin-echo MR sequence--experience in six patients

PURPOSE

To determine if hypointense lesions clearly outline on T2-weighted fast spin-echo (SE) magnetic resonance (MR) images obtained during coagulative interstitial laser-induced thermotherapy (LITT) of a prostate with benign hyperplasia.

MATERIALS AND METHODS

In six patients with benign prostatic hyperplasia (BPH), 12 LITT treatments were followed online with repetitive axial T2-weighted fast SE imaging (repetition time, 3,700 msec; echo time, 138 msec; acquisition time, 19 seconds). Development, time course, correlation with interstitial tissue temperature, and diameters of hypointense lesions around the laser diffusor tip were investigated. Lesion diameters on T2-weighted images acquired during LITT were compared with diameters of final lesions on T2-weighted images and unperfused lesions on enhanced T1-weighted SE images obtained at the end of therapy.

RESULTS

Hypointense lesions developed within 20-40 seconds of LITT. Average correlation coefficients between interstitial temperature development and signal intensity development were 0.92 during LITT and 0.90 after LITT. Regression slopes were significantly steeper during LITT (0.67% signal intensity change per degree Celsius) than after LITT (0.47% per degree Celsius; P = .038). Lesions remained visible after LITT for all procedures. Average maximum diameters of lesions were 1-3 mm larger during LITT than after LITT (P = .0006-.019).

CONCLUSION

Repetitive T2-weighted fast SE MR imaging during interstitial coagulative LITT of BPH demonstrates the development of permanent hypointense prostate lesions. However, posttherapeutic lesion diameters tend to be overestimated during LITT.

Prediction of toxicity but not of clinical course by determining carboplatin exposure in patients with epithelial ovarian cancer treated with a combination of carboplatin and cisplatin

We present the data from 105 patients with primary epithelial ovarian cancer, who received up to 6 cycles of carboplatin (300 mg/m2) and cisplatin (100 mg/m2) as one treatment arm of a prospective randomized trial. Values for first-course carboplatin area-under-the-curve (AUC) were determined retrospectively. WHO grade 3-4 thrombocytopenia was found in 10% of patients with low AUC (AUC <4 mg/ml x min), but in 44.6% of patients with high AUC (AUC 4 mg/ml x min) (chi-square p<0.0001). No single case of ototoxicity was found in the low AUC group but in 12% of patients in the high AUC group (chi-square p=0.003). Determination of carboplatin AUC may prevent ototoxicity and severe thrombocytopenia for the first cycle of combined treatment with carboplatin and cisplatin.

Effect of the dilution rate on the mode of oscillation in continuous cultures of Saccharomyces cerevisiae

The growth properties of the asymmetric budding yeast Saccharomyces cerevisiae were analysed during spontaneous oscillations in continuous cultures at varying dilution rates D. The length of the oscillation period changed between 1.4 and 14 h in response to the decrease of dilution rate from 0.15 to 0.05 h-1. The distribution of parent and daughter cells in the population was determined microscopically after staining the bud scars and DNA. Most of the data obtained fits a theoretical population balance model assuming two-classes of subpopulations and integer ratios between the generation times of both classes. Some data has to be described by an extended population model assuming there is one parent and two daughter cell classes. How changes of dilution rate may cause an accidental switch of the mode of oscillation is demonstrated. Glucose consumption and metabolite production were measured off-line by enzymatic methods and gas exchange was monitored on-line. All these data of one period point to internal and external signals responsible for the synchronisation of the cell cycle.

Predictability of the size of laser-induced lesions in T1-Weighted MR images obtained during interstitial laser-induced thermotherapy of benign prostatic hyperplasia

The purpose of this study was to predict diameters of lesions induced by laser-induced thermotherapy (LITT) of benign prostatic hyperplasia (BPH) from MRI signal/tissue temperature correlations during on-line monitoring with a temperature-sensitive fast low-angle shot (FLASH) sequence. Twenty LITT procedures with Nd:YAG (1,064 nm) and diode (830 nm) lasers were monitored on line with a T1-weighted FLASH sequence at 1.5 Tesla. Interstitial prostate temperature (T) was measured on line in 10 LITT procedures and laser energy deposition in 12. Slopes of linear regression curves for signal intensity (SI) over T were applied to determine SI at 60 degrees C to estimate diameters of intraprostatic LITT lesions. Diameters of unperfused LITT lesion cores in contrast-enhanced T1-weighted images served as gold standards. Linear regression curves with an average slope of -.54% SI/degrees C were obtained in 17 LITT procedures. Correlation coefficients were r = .92-.95 for SI/T and SI/energy deposition. Baseline variation of SI at body temperature was +/-3.9%, corresponding to +/-7 degrees C. Prediction of size (13 lesions) from on-line FLASH imaging was correct in 10 of 13, whereas 3 lesions were overestimated. Prediction of LITT lesion diameters from on-line MRI monitoring is possible with a temperature-sensitive FLASH sequence in the prostate. Accuracy may suffice to assign target regions of interest to tissue locations to be protected from coagulation.

[MRI monitoring before, during and after interstitial laser-induced hyperthermia of benign prostatic hyperplasia. Initial clinical experiences]

PURPOSE

To assess the clinical value of MRI in patients with benign prostatic hyperplasia (BPH) before, during, and after interstitial laser-induced thermotherapy (LITT) of the prostate.

METHODS

Ten patients with symptomatic BPH had MRI examinations of the prostate 48 h before and after LITT. Online monitoring with MRI at 1.5 T of interstitial Nd:YAG laser energy deposition in the prostate was performed in two patients, repeating a T1-weighted FLASH sequence (TR 100 ms, TE 5 ms, flip angle 90 degrees) every 20 s. Follow-up MRI examinations 2-3 weeks, 6-8 weeks, and 6-12 months after LITT were carried out in eight patients, using T2-weighted FSE images and contrast-enhanced T1-weighted SE images.

RESULTS

The prostate was well delineated in all patients on T2-weighted FSE images, with a rather homogeneous peripheral gland and an inhomogeneous central gland. Volume measurements yielded reproducibilities of 3.2%-4.7%. Signal intensity in the FLASH sequence decreased during LITT, both in the prostate in vivo and in specimens of bovine prostate and seminal vesicles in vitro, with signal developments running in parallel. Areas of energy deposition and signal alteration were not sharply delineated. The latter margin of the laser-induced lesions could not be predicted from the FLASH images, while the tip of the laser fibre was easily recognized. Contrast-enhanced T1-weighted MR images immediately after LITT clearly demarcated low signal intensity laser lesions from high signal intensity surrounding prostate tissue. Follow-up examinations showed a decrease of 20% of prostate volume over a period of 6-12 months after LITT. Correlation between prostate volume development and lesion volume alteration was 0.85-0.90 (P = 0.002-0.007) at all follow-up times.

CONCLUSIONS

MRI allows rather precise recognition of intraprostatic alterations after LITT, including volume changes over a period of up to 1 year after therapy that can be predicted immediately after LITT. While laser energy deposition in the prostate can be monitored by MRI with T1-weighted FLASH sequences as a function of temperature alteration, it is not possible to determine the lesion margins immediately from the FLASH images. Online temperature development map generation will be necessary to influence on-going LITT procedures with MRI.

[Initial results with MRI-controlled laser-induced interstitial thermotherapy of head and neck tumors]

Laser-induced interstitial thermo-therapy (LITT) was introduced as a minimally invasive form of therapy for tumors in different anatomic regions. However, in the orofacial region, it has not been used so far for inoperable T4 carcinomas. Since vascular and neural structures are often close to the tumor or are even involved, online monitoring of LITT is necessary. The aim of our study was to establish a method of monitoring LITT with MRI (magnetic resonance imaging) in the orofacial region. Five patients with T4 carcinomas of the orofacial region underwent LITT under anesthesia. A 1.5 T whole-body imager with a circular polarized head coil was used. Before and after the intervention, the region of interest was studied using T1- and T2-weighted sequences in axial and coronal planes, with and without contrast enhancement (intravenous Gd-DTPA). Temperature distribution was monitored with a T1-weighted 2D-FLASH (fast low angle shot) sequence. The positioning of the optical fibers was monitored with MRI. Nd:YAG laser equipment was used for laser application. The necrosis was best seen on contrast-enhanced MRI. Immediately after LITT, the outcome could be determined by MRI. We proposed that MRI-guided LITT be used for neoplasms in the orofacial region at advanced stages.

Influence of delayed diagnosis on established prognostic factors in endometrial cancer

To evaluate the influence of delayed diagnosis on prognostic factors in endometrial cancer, we conducted a retrospective chart analysis based on the data of 116 postmenopausal patients with FIGO stage I-IV endometrial carcinoma. The interval from the first episode of post-menopausal vaginal bleeding to definitive, histological diagnosis (bleeding interval) was compared with tumor stage and various histomorphologic features in endometrial cancer. The mean bleeding interval was 12.7 +/- 17.8 weeks in 74 patients with FIGO stage IA, IB endometrial carcinoma and 35.2 +/- 69.3 weeks in 42 patients with stage IC-IV disease (t-test, p: 0.011). FIGO stage IA, IB disease was diagnosed in 23/26 (88%) patients with a bleeding interval <4 weeks, and in 22/34 (64%) and 29/56 (51%) patients with bleeding intervals of 4-8 weeks and >8 weeks, respectively (Chi-square 10.358, p=0.006). The correlation with histologic grade, lymph-node status, vessel invasion and histologic subtypes did not reach statistical significance. Our data confirm the clinical impression that postmenopausal vaginal bleeding is an early symptom in patients with endometrial cancer, and that advanced disease in the majority of cases might come from delayed diagnosis in women with poor compliance.

The influence of obesity on the disease-free survival in primary breast cancer

Hyper-estrogenism is more common in obese than in non-obese women. Consequently obesity has been shown to increase the risk of hormone department tumors. Some investigators have claimed that obesity at the time of primary treatment may be an independent prognostic factor for breast cancer, but this issue is still controversial. Therefore, we conducted a retrospective analysis to assess the influence of obesity at the time of primary treatment on disease-free survival (DFS). Obesity was defined as an excess of more than 25% of ideal weight according to Broca's index ([Height (cm) -100])-10%). The Cox-model was used for multivariate analysis. Mean follow-up was 61 (range 6-126) months. 295 (62.3%) patients were classified as of normal weight and 178 (37.6%) as obese. Mean excess of ideal weight was 8.9 kilograms (kg) in premenopausal and 13.9 kg in postmenopausal patients (non-parametric t-test p < 0.00001). Patients with tumor size < 20mm, 20-50mm and > 50mm had a means excess of the real weight of 10.6kg, 12.5kg and 16.1kg, respectively (non-parametric t-test p < 0.0001). Percentual excess of real weight compared to ideal weight was 22.4 [+/-21.2] kg in patients without recurrence and 21.5 [+/-21.9] in patients with recurrent disease (nonparametric t-test p = 0.7256). Univariate analysis revealed no significant association between obesity and the DFS. Multivariate analysis identified axillary lymph node involvement as the only statistically significant prognostic factor for disease-free survival (RR 1.55; 95%-confidence interval 1.02-2.36; p:0.0368). Because of the high correlations and node-status, tumor size and histological grading, the other factors failed to be prognostically relevant in this analysis. Obesity was not found to influence DFS of patients with primary breast cancer and is therefore unlikely to constitute an independent prognostic factor. It may, however, contribute to delayed diagnosis, since a significant proportion of obese patients were diagnosed with local advanced disease.