Satisfactory Margin Research Articles

Custom osteotomy guides for resection of a pelvic chondrosarcoma

Custom osteotomy guides for resection of a pelvic chondrosarcoma

Breast Tumor Localization Using Simultaneous Perturbation Stochastic-Neural Algorithm

Many impalpable or occult breast cancers cannot be localized using imaging techniques like mam- mography and ultrasound. An accurate localization of the tumor is, however, essential to guide the surgeon to the lesion, and ensure its correct and adequate removal with satisfactory excision margins. Current breast tumor localization techniques are invasive and often result in a cosmetic disfigurement. In this paper, we use the ultrawide band radar-based microwave breast imaging technique to non-invasively localize (impalpable) tumors in the breast. We consider four clinically important lesion features: location, size, depth and spatial orientation within the breast. A comparison of the energy of the received signal from healthy and cancerous breasts exhibits some remarkable differences in some frequency bands. We, therefore, use the energy spectrum of the receiving antenna signal decomposed by wavelet transform as the input to a Simultaneous Perturbation Neural Network (SPNN) classifier. Fur- thermore, we determine the optimum structure and gains of the SPNN, in terms of optimum initial weights and optimum number of nodes in the hidden layer. We use CST Microwave Studio to simulate a data set of 1024 cancer cases with various tumor location, size, depth and direction inside the breast. Our results show that the proposed algorithm gives accurate localization of the breast lesion, and possesses a high sensitivity to small tumor sizes. Additionally, it can accurately detect and classify multiple tumors with short learning and testing time.

Computer-assisted planning and navigation improves cutting accuracy during simulated bone tumor surgery of the pelvis

Background: Resection of bone tumors within the pelvis requires good cutting accuracy to achieve satisfactory safe margins. Manually controlled bone cutting can result in serious errors, especially due to the complex three-dimensional geometry, limited visibility, and restricted working space of the pelvic bone. This experimental study investigated cutting accuracy during navigated and non-navigated simulated bone tumor cutting in the pelvis.Methods: A periacetabular tumor resection was simulated using a pelvic bone model. Twenty-three operators (10 senior and 13 junior surgeons) were asked to perform the tumor cutting, initially according to a freehand procedure and later with the aid of a navigation system. Before cutting, each operator used preoperative planning software to define four target planes around the tumor with a 10-mm desired safe margin. After cutting, the location and flatness of the cut planes were measured, as well as the achieved surgical margins and the time required for each cutting procedure.Results: The location of the cut planes with respect to the target planes was significantly improved by using the navigated cutting procedure, averaging 2.8 mm as compared to 11.2 mm for the freehand cutting procedure (p < 0.001). There was no intralesional tumor cutting when using the navigation system. The maximum difference between the achieved margins and the 10-mm desired safe margin was 6.5 mm with the navigated cutting process (compared to 13 mm with the freehand cutting process).Conclusions: Cutting accuracy during simulated bone cuts of the pelvis can be significantly improved by using a freehand process assisted by a navigation system. When fully validated with complementary in vivo studies, the planning and navigation-guided technologies that have been developed for the present study may improve bone cutting accuracy during pelvic tumor resection by providing clinically acceptable margins.

Surgical treatment of bone tumor using computer-assisted navigation

Objective To analyze the security and effectiveness of computer-assisted navigation used in the preoperative design,accurate resection and reconstruction of bone tumor. Methods From February 2009 to August 2011,tumor resections and reconstructions assisted by computer-assisted navigation were performed in 39 patients with musculoskeletal tumor.They were 21 males and 18 females.Tumors occurred in the pelvis in 20 cases,in the distal femur in 9.in the proximal tibia in 6 and in the spine in 4.The preoperative CT scans and MRI images of all patients were transformed into data at.dicom format and imported into the navigation system.The computer analyzed the data,reconstrueted the anatomical structure of the tumor,displayed and marked the accurate border of the tumor.After the area was defined,resection of the bonc tumor was perfomed strictly under the guidance of navigation,and reconstruction accomplished with the proper prostheses or allograft bones preoperatively designed.The local recurrence of tumor and surgical margin were appraised postoperatively.and the function was assessed according to MSTS93 evaluation system.Results The intraoperative anatomic registration points were coincident with those by the preoperativu design,with an average crror of 0.52mm (from 0.4to 0.7mm).Accurate tumor resection and satisfactory reconstruction were performed on schedule in 36 patients,without intraoperative injury to nerves,vessels or organs.The pathological tumor samples showed satisfactory surgical margins without residual tumor.The avcrage follow-up was 19.5 months (range,3 to 32 months).Local recurrence was found in 5 malignant cases,including 3 pelvic and 2 limb cases as well as 3 cases of pulmonary metastasis.The average MSTS93 functional soore was 24.8 (from 22 to 28) points. Conclusions Computer-assisted navigation system is a safe and effectiv assistance for accurate resection and reconstruction of musculoskeletal tumor.It helps avoiding blindness in tumor resection and arbitrary reconstrution.It can also reduce the recurrence rate and improve functional recoveru. Key words: Surgcry, computer-assisted; Bone neoplasms; Reconstructive surgical procedures

Survival, Local Recurrence, and Function After Pelvic Limb Salvage at 23 to 38 Years of Followup

Malignant pelvic tumors frequently pose challenges to surgeons owing to complex pelvic anatomy and local extension. External hemipelvectomy frequently allows adequate margins but is associated with substantial morbidity and reduced function. Limb salvage is an alternative approach when adequate margins can be achieved, but long-term function and survival are unclear. We therefore determined the long-term survival; development of late local recurrence and metastases; function; and need for further reconstructive procedures for patients undergoing limb salvage for treatment of malignant pelvic tumors. We retrospectively reviewed 60 patients treated with pelvic limb salvage before 1989. We reviewed medical records and sent questionnaires incorporating Musculoskeletal Tumor Society (MSTS) and Toronto Extremity Salvage scores to the 38 patients who had no evidence of disease in 1989; 15 patients responded. Minimum followup was 23 years (median, 30 years; range, 23-38 years). Overall survival rate of the 60 patients was 45%: 100% Stage IA, 75% Stage IB, 31% Stage IIB, and 0% Stage III were alive. Late local recurrence developed only in patients with chondrosarcoma (three of 24). Two patients developed late distant bone metastases. Function declined: the MSTS score of the 15 patients who completed a questionnaire decreased 23%. Two patients had further reconstructive procedures. At 23- to 38-year followup, we believe pelvic limb salvage is a reasonable treatment if satisfactory margins can be achieved. If a patient with pelvic sarcoma is free of disease 5 years after sarcoma resection, the subsequent risk of death from sarcoma appears to be low. Late local recurrence remains a risk in patients with pelvic chondrosarcoma. Patient-reported function of the salvaged limb declined with long-term followup. Level IV, therapeutic study. See Guidelines for Authors for a complete description of levels of evidence.

An ecological risk assessment for triclosan in the terrestrial environment

Triclosan (2,4,4'-trichloro-2'-hydroxydiphenyl ether) is a broad-spectrum bactericide used throughout North America and Europe for a variety of antimicrobial functions. This paper addresses the risk to terrestrial organisms from several potential exposure pathways: Exposure experienced by earthworms, terrestrial plants, and soil microorganisms as the result of the use of sewage sludge containing triclosan as an agricultural soil amendment; secondary exposure by birds and mammals from consumption of earthworms that have been exposed to triclosan in soil; and secondary exposure by birds and mammals from consumption of fish exposed to triclosan as the result of wastewater treatment discharges. The assessment found satisfactory margins of safety for plants, earthworms, birds, fish, mammals, and soil microorganisms. The lowest margins of safety were for nontarget plants (100 for the typical scenario and 8 for the upper-bound scenario). However, these margins of safety are still above the European Union (EU) recommended fivefold assessment value for nontarget plants and are based on cucumber results from a vegetative vigor study conducted in quartz sand that is of limited relevance for risk assessment. In a pre-emergence study conducted in a more relevant soil (sandy loam), cucumbers showed no response to triclosan at the highest dose tested (1,000 microg/kg). A recent study provides limited field measurements of soil and earthworm concentrations. While that study finds higher soil and earthworm concentrations than were estimated in the present study, even these higher concentrations do not indicate significant risks.

Analysis of longitudinal beam dynamics behavior and rf system operative limits at high-beam currents in storage rings

A dynamics simulation model is used to estimate limits of performance of the Positron-Electron Project (PEP-II). The simulation captures the dynamics and technical limitations of the Low Level Radio Frequency (LLRF) system, the high-power RF components and the low-order mode coupled bunch longitudinal beam dynamics. Simulation results showing the effect of non-linearities on the LLRF loops, and studies of the effectiveness of technical component upgrades are reported, as well as a comparison of these results with PEP-II measurements. These studies have led to the estimation of limits and determining factors in the maximum stored current that the Low Energy Ring/High Energy Ring (LER/HER) can achieve, based on system stability for different RF station configurations and upgrades. In particular, the feasibility of the PEP-II plans to achieve the final goal in luminosity, which required an increase of the beam currents to 4A for LER and 2.2A for HER, is studied. These currents are challenging in part because they would push the longitudinal low-order beam mode stability to the limit, and the klystron forward power past a level of satisfactory margin. An acceptable margin is defined in this paper, which in turn determines the corresponding klystron forward power limitation.

Epithelial salivary gland tumors of children and adolescents in west China population: a clinicopathologic study of 79 cases

Determine the clinical and histopathologic features of epithelial salivary gland tumors of children and adolescents. A total of 79 cases of epithelial salivary gland tumors of children and adolescents were retrieved from the files. Information about demographic, clinical, histopathologic characteristics, and follow-up status were analyzed. Sixty tumors (75.9%) were benign and 19 (24.1%) malignant. The most common tumor overall was pleomorphic adenoma (PA). The parotid was the most frequently involved site (43.0%). PA was the most common type of benign tumor. The most common malignant tumor was mucoepidermoid carcinoma. Five patients with parotid PA and two cases with palate myoepithelioma showed local recurrences. One patient with mucoepidermoid carcinoma showed local recurrences and died from the tumor 3 years after the initial treatment. One patient with adenocarcinoma presented local and neck recurrences, and died 4 years after initial treatment. Our data showed that the salivary gland tumors in children and adolescents may be the higher incidence of benign tumors, especially of PA; the slightly higher tendency for female predominance; the higher incidence of parotid glands. Mucoepidermoid carcinoma was the most common malignant tumor, with majority of low grade. Initial treatment should be planned to excise the tumor completely with satisfactory margins. The neck dissections or postoperative radiotherapy were performed in patients with low differentiation malignancies, or patients who present nodal metastasis or with clinically suspicious regional metastasis.

A Biventricular ICD System with Biventricular Defibrillation

We describe the case of a 59-year-old gentleman with severe dilated cardiomyopathy requiring implantation of a dual-chamber biventricular implantable cardioverter-defibrillator (ICD). High defibrillation thresholds (DFT) were encountered at implant with an inadequate defibrillation safety margin. Testing of all possible shock vectors/polarities with and without the SVC coil and optimization of the distal RV coil position all proved inadequate. A satisfactory defibrillation safety margin was achieved following placement of a second lead in the coronary sinus to enable biventricular defibrillation. This case highlights an additional strategy for combating high DFTs and is an option even in dual-chamber biventricular ICD systems.

Financing Foodstuff Marketing In Akwa Ibom State, Nigeria: Some Considerations

The introduction of micro credit schemes to provide financial services to the small operators in the food marketing industry deserve some caution because available literature confirms that formal credit programme involving small operators in the agricultural sector have low repayment history. This study assessed how micro finance schemes directed at the small operators in the food marketing industry can package result oriented financial services for the success of the lending schemes. The report is based on panel data obtained in a research involving 116 food retailers in Akwa Ibom State. The simple random sampling procedure was used to select the respondents. Descriptive statistics such as means and percentages, and the multiple regression analytical technique were used to analyze the data. The results show that among the palm oil, grains, vegetable and seafood sellers transport cost had significant effects on the marketing margin, are positively related but unit increase in their numbers adds less than proportionately to the marketing margin. Among the palm oil and grain sellers, the quantity of produce handled had significant effect on, are positively related to, but bring about a less than proportionate increase to the marketing margin. For seafood and vegetable sellers, more margin can be ensured if more quantity of the seafood are handled but efforts must be made to assist the traders handle such quantity that will bring about more than proportionate increase in the marketing margin. Younger sellers make better margin comparatively. Micro finance schemes directed at the operators in the food marketing sub sector must be designed to provide financial and non-financial services that are accompanied with appropriate package of dynamic and static incentives to motivate and compel loan beneficiaries to repay loans. The credit package must include efforts to direct credit to younger sellers, reduce the transport cost and increase the quantity of produce handled so as to ensure that the operators earn satisfactory margins to repay loans. More importantly regular repayment schedule designed to match the time pattern of earnings of the beneficiaries and appropriate research instrument must be packaged alongside these financial and non-financial services to add impetus to loan repayment, identify problems and solutions that can make the micro-finance scheme a going concern. KEY WORDS: Micro finance, marketing margin, Loans repayment. Global Journal of Agricultural Sciences Vol.3(1&2) 2004: 35-40

Radiotherapy for local control of osteosarcoma

Local control of osteosarcoma in patients for whom a resection with satisfactory margins is not achieved can be difficult. This study evaluated the efficacy of radiotherapy (RT) in this setting. We identified 41 patients in our sarcoma database with osteosarcomas that either were not resected or were excised with close or positive margins and who underwent RT with external beam photons and/or protons at our institution between 1980 and 2002. Patient charts were reviewed to assess local control, progression-free survival, metastasis-free survival, and overall survival. The anatomic sites treated were head/face/skull in 17, extremity in 8, spine in 8, pelvis in 7, and trunk in 1. Of the 41 patients, 27 (65.85%) had undergone gross total tumor resection, 9 (21.95%) subtotal resection, and 5 (12.2%) biopsy only. The radiation dose ranged from 10 to 80 Gy (median 66). Twenty-three patients (56.1%) received a portion of their RT with protons. Chemotherapy was given to 35 patients (85.4%). Of the 41 patients, 27 (65.85%) were treated for localized disease at primary presentation, 10 (24.4%) for local recurrence, and 4 (9.8%) for metastatic disease. The overall local control rate at 5 years was 68% +/- 8.3%. The local control rate according to the extent of resection was 78.4% +/- 8.6% for gross total resection 77.8% +/- 13.9% for subtotal resection, and 40% +/- 21.9% for biopsy only (p < 0.01). The overall survival rate according to the extent of resection was 74.45% +/- 9.1% for gross total resection, 74.1% +/- 16.1% for subtotal resection, and 25% +/- 21.65% for biopsy only (p < 0.001). Patients with either gross or subtotal resection had a greater rate of local control, survival, and disease-free survival compared with those who underwent biopsy only at 5 years (77.7% +/- 7.5% vs. 40% +/- 21% [p <0.001], 73.9% +/- 8.1% vs. 25% +/- 21.6% [p <0.001], and 51.9% +/- 9.1% vs. 25% +/- 21.6% [p <0.01], respectively). Overall survival was better in patients treated at primary presentation (78.8% +/- 8.6% compared with 54% +/- 17.3% for recurrence) p <0.05). No definitive dose-response relationship for local control of tumor was seen, although the local control rate was 71% +/- 9% for 32 patients receiving doses > or =55 Gy vs. 53.6% +/- 20.1% for 9 patients receiving <55 Gy (p = 0.11). Of 15 patients with tumors >5.3 cm, 9 received doses > or =55 Gy and the local control rate was 80% +/- 17.9%, and 6 received doses <55 Gy with a local control rate of only 50% +/- 25% at 5 years (p = 0.16). Among patients who underwent gross total resection, the local control rate was 77.5% +/- 9.95% in 22 patients with negative margins vs 66.7% +/- 27.2% in 3 patients with positive margins (p = 0.54). Two patients had unknown margin status. RT can help provide local control of osteosarcoma for patients in whom surgical resection with widely, negative margins is not possible. It appears to be more effective in situations in which microscopic or minimal residual disease is being treated.

Evaluation of motor toxicity and anticonvulsant efficacy of barbiturates and benzodiazepines in a bicyclophosphate seizure model in mice

1. 4-Alkyl derivatives of 2,6,7-trioxa-l-phosphabicyclo [2.2.2] octane-I-oxide [Bicyclophosphates (BP)] are highly toxic convulsants and potent GABAA receptor antagonists. 2. The effects of various clinical used anticonvulsant drugs, barbiturates and benzodiazepines, on motor performance and 4-isopropylbicyclophosphate (IPBP), a homologue of BP, induced myoclonic and generalized tonic-clonic seizures were investigated in mice. 3. The anticonvulsant drugs were IP administered 30 min. prior to the inverted screen test, a measure of minimal neurological deficit, and were then challenged with a 97% convulsant dose of IPBP (0.15 mg/kg, SC). 4. The results show that: 1) benzodiazepines are more likely to have favorable motor toxicity and anticonvulsant profiles than barbiturates. 2) Various doses of these drugs that did not significantly cause motor impairment increase the mean latencies to myoclonic and generalized tonic-clonic seizures. 3) The increase in anticonvulsant activity is associated with a comparable increase in motor impairment. 4) Only 45-0088-S, an open-ring derivative of 1,4-benzodiazepines, and clonazepam have protective indices of more than 5, a satisfactory margin of safety. 5. The potential use of 45-0088-S and clonazepam in the treatment of BP-induced seizures should be explored further.

Ressecção videolaparoscópica de hemangiopericitoma do estômago

In the present case (77 years-old woman), the diagnosis on an extramucosal lesion by endosonography was leiomyoma or schwanoma. Radiological exam of the upper digestive tract with barium and abdominal computed tomography confirmed the site of the lesion at the level of the lesser curvature. The operative technique followed the steps of the laparoscopic partial gastric resection (wedge resection) for gastric mesenchymal tumours, described elsewhere. The Endo-GIA stapler was introduced through the 12mm port in the right upper quadrant. Proper positioning of the stapler over the lesser curvature and a satisfactory margin of tissue around the mass were attained. Nine sequential firings of the Endo-GIA 30 were needed to completely surround the mass. Histopathological diagnosis was a spindle-cell tumour measuring 3cm in diameter. Mitotic index was measured at almost null. The neoplastic cells were strongly reactive for vimentine and CD34 and negative for the immunohistochemical markers S-100 protein, muscle actin, desmin and Ag linked to VIII factor. There was a slight reaction with keratin (+/+++). The XIIIA factor reaction revealed less than 5% of dendritic elements. These data favour a vascular cell origin better than smooth muscle cell origin. In conclusion it was a gastric hemangiopericytoma. Follow-up showed no recurrence at seven years.

The unsatisfactory margin in breast cancer surgery

Background: Surgical margin involvement with breast cancer usually results in obligatory reexcision or mastectomy. While unalterable occult host and pathologic factors may interfere with margin clearance during the initial excision, it is possible that alterations in surgical technique might increase the likelihood of obtaining satisfactory margins. Methods: Two hundred and thirty-five patients who were candidates for breast conservation therapy were identified for 1991 and 1996 using the Tumor Registry. Margins were defined as “unsatisfactory” if there was microscopic involvement with tumor or the margin was close at initial excisional biopsy and the surgeon opted for reexcision. Multiple logistic regression analyses of factors associated with margin status were performed. Results: One hundred thirty-two (56%) patients had positive or close (unsatisfactory) margins; this rate increased from 51% in 1991 to 59% in 1996. Patients with unsatisfactory margins underwent more procedures (mean 2.0 versus 1.2; P <0.0001) than patients whose margins were satisfactory. The breast conservation rate for patients with unsatisfactory margins was 64% compared with 99% for patients with satisfactory margins. A multiple logistic regression demonstrated that patients with unsatisfactory margins were 67 times more likely to have a mastectomy than patients whose margins were satisfactory after adjusting for other significant factors ( P <0.0001). The practice of fine needle aspiration biopsy, orientation of specimen margins by the surgeon, and reexcision of tumor at the first operation were statistically significant technical factors in obtaining satisfactory margins. Significant pathology factors were extensive intraductal component (EIC), lobular or ductal extension, and tumor size. Conclusion: These data show that technical factors in the surgical management of breast cancer, as well as biological factors such as EIC, can influence the success of breast conservation.

Surgical Management of Malignant Tumors of the Jaws

Summary Surgery for malignant tumors of the maxillofacial region has benefited significantly from advances in imaging technology and instrumentation and in maturation of craniofacial and orthognathic reconstructive surgical techniques during the past two decades. These developments allow the maxillofacial oncologic surgeon to precisely visualize the anatomic involvement of the malignant process in order to better determine exactly which surgical ablative procedure is of greatest benefit to the patient. Reconstructive surgical options are available that are not solely dependent on local tissues or delayed staged tissue transfers, enabling the surgeon to obtain satisfactory resection margins at the ablative surgical site and at the same time offering the patient the possibility of immediate restoration of anatomic form and an expeditious return of function depending on the specific malignant tumor treated. This review deals with some of the most common approaches to surgically treating malignancies of the maxilla and mandible, in addition to providing a brief review of malignant tumor-specific behavior and surgical recommendations as they relate to those malignancies of the jaws that have traditionally been treated through surgery. It is hoped that those colleagues dealing in maxillofacial surgical oncology will continue to report their findings so that these unfortunate patients can continue to benefit from evolving advances in this exciting field.

Adapting to survive

The machine tool industry occupies an unenviable position directly in the firing line of manufacturing industry as a whole. The inevitable cyclical variations in demand and output can have direct repercussions on levels of investment, often involving machine tool purchasing. Birmingham based Cincinnati Milacron UK was no exception and found itself in this position in the latter half of the 1980s. The produce range was both sophisticated and of high performance capability, but it employed very costly design and manufacturing methods. The resultant high prices, coupled with the level of competition, did not produce satisfactory operating margins. Major changes were required, both in the product range and in the production of this range, if the company was to survive and prosper. A strategy for survival had to be developed that would ensure significant improvements in all of the fundamental business measures arising out of sophisticated CNC machine tool design and manufacture. In addition, a culture change within the organisation was necessary, to improve radically results in design time and accuracy, performance specification, design for manufacture and number of components used, manufacturing lead times, inventory control, price and appearance, installation time, reliability and marketing. A concurrent engineering strategy was implemented.

Intrapulmonary benign fibrous tumor of the pleura

Primary pleural tumors are commonly divided into diffuse and localized typesJ The diffuse malignant mesothelioma, associated with asbestos exposure, is the most commonly recognized lesion of this group. The localized variety is less well defined and has been described by a variety of names, including benign mesothelioma, fibrosJng mesothelioma, subpleural fibroma, and localized fibrous tumor of the pleura. The Clinical behavior and histologic features of these tumors are quite different from those of the diffuse type. Some investigators have suggested thai: the term mesothelioma is confusing. 2 The majority of these benign fibrous tumors appear as polypoid lesions and have rarely been reported as intraparenchymal lesions? A 20-year-old white woman had a routine chest roentgenogram after a fall from a horse. Before that time she had been completely free of symptoms. She had no history of cough, shortness of breath, sputum production, or tobacco use. The x-ray film revealed a large mass within the upper !obe of the right lung. A subsequent computed tomographic scan (Fig. 1) showed the proximity of the lesion to the origin of the right upper lobe bronchus. A bronchoscopic study showed an endobronchial lesion consistent with inflammation. Endobronchial biopsies were performed, but a satisfactory histopathologic diagnosis could not be determined from these specimens. At thoracotomy a 3 cm tumor was seen involving the basal segment of the right upper lobe. Associated atelectasis and inflammation involved the superior segment of the right lower lobe. For complete excision of the tumor with satisfactory margins, a sleeve resection of the right upper lobe had to be performed. The masg was well circumscribed and measured 2.5 by 3 cm. A cross section revealed an intrapulmonary wellcircumscribed whorled white nodule with central calcification. It encircled the bronchus but did not grossly invade the bronchus. The tumor extended to the pleural surface without involving the pleura. No necrosis was appreciated. The remaining lung tissue had several areas of atelectasis and inflammation that appeared to be associated with the mass. Histologically, the lesion showed a proliferation of spindle ce!ls in haphazardly arranged fascicles and a storiform pattern. The cells were bland in appearance, and a low mJitotic rate of less than 1 mitosis per 10 high-power fields was appreciated. The cytoplasmic bor-

Accuracy limits of ultrasonograhic estimation of human fetal urinary flow rate

Objective: Our purpose was to define the accuracy of currently available methods of ultrasonographically estimating human fetal urinary flow rate in a controlled setting.Study Design: Eleven fetal cadavers were studied in a water bath. Saline solution was incrementally infused into the bladder to simulate a rate of 1 ml/min. Serial fetal bladder volumes were calculated from ultrasonographic measurements by means of the ovoid volume formula (ovoid volume = 4/3 · π · (D1 · D2 · D3)/8 and ellipse sagittal-area and coronal-area volume formulas that we previously reported (Sagittal-area volume = 0.46323 + 1.39394 · Sagittal area and Coronal-area volume = 1.20640 + 1.07603 · Coronal area). Fetal urinary flow rate was determined by (1) subtracting the mean of two fetal bladder volumes at the start and end of a simulated 30-minute bladder filling or (2) linear regression of three, four, five, and six fetal bladder volume observations against time. The means of fetal urinary flow rate estimates and errors derived with each method were compared to the actual rate of 1 ml/min by means of the Student t test.Results: The volume subtraction technique with ovoid volume yielded a fetal urinary flow rate of 1.68 ml/min (95% confidence interval 0.86 to 2.50 ml/min). Similar overprediction of fetal urinary flow rate occurred with regression with ovoid volume (1.45 ml/min, 95% confidence interval 0.61 to 2.29 ml/min). Estimated fetal urinary flow rates (from sagittal-area volume and coronal-area volume (0.99 ml/min, 95% confidence interval 0.64 to 1.34 ml/min) were significantly more accurate than those from ovoid volume (p < 0.0001). Regression with 3 (95% confidence interval ±40%) or 4 points (95% confidence interval ±37%) was marginally less accurate than with 5 (95% confidence interval ±36%) or 6 points (95% confidence interval ±35%, p = 0.02).Conclusions: Ultrasonographic estimates of fetal urinary flow rate based on the ovoid volume formula overestimate the true rate by 40% to 70%. Fetal urinary flow rate calculated by regression of three to six sagittal or coronal bladder area measurements is a better estimate of true rate with a satisfactory margin of uncertainty. This technique can be used to predict human fetal urinary flow rate with an expected accuracy of ±35%.

Laparoscopic colectomy:

The aim of this study was to review the progress made in removing the colon with laparoscopic technique. Literature review and personal experiences. Laparoscopy is a safe and efficacious technique for the removal of segments of the colon for benign indications. Malignant lesions can be removed laparoscopically with satisfactory margins, but long-term efficacy has not been established. Laparoscopic-assisted surgery appears to be associated with improved preservation of bowel and other physiologic function while decreasing narcotic requirements and length of hospital stay. Laparoscopy will likely be the technique of choice for removing segments of the colon in select situations.

Sarcomas of the flexor fossae in children: Is amputation necessary?

Successful management of sarcomas of the extremities in children implies not only achievement of local control but also satisfactory function and maintenance of the growth potential. The popliteal and antecubital fossae, because of their complex neurovascular anatomy, all of which is essential, make resection with satisfactory margins difficult. We reviewed our experience with 14 patients (3 to 20 years old; median, 13 years) with soft tissue sarcomas arising in the popliteal (11 patients) or antecubital (3 patients) fossae. There were four rhabdomyosarcomas (3 alveolar, 1 embryonal) and 10 other sarcomas, the most frequent being synovial sarcoma (5 patients). Chemotherapy was given to all patients with rhabdomyosarcomas. The one patient presenting with metastatic disease was treated, after biopsy of the primary, by chemotherapy and radiation and survived 21 months. In three patients, the primary management was an above-the-knee amputation and two of three survived (3 and 43 months). In 10 patients a wide local excision of the primary tumor was performed. Radiation therapy was administered to five, either as external beam (3 patients) or as brachytherapy (2 patients). In this group, there were no local recurrences. Four patients remain free of disease (4 months to 18 years) and one developed pulmonary metastasis. Among the five non-irradiated patients, three developed local recurrences, requiring above-the-knee amputation for disease. The fourth patient relapsed in the lung and only one of the five is free of disease at 36 months. Of the 8 patients not treated with amputation, one acquired a leg length discrepancy, which required correction, and one has a minimal extension deficit of the knee. These data suggest that: (1) preservation of a functional limb is possible for a majority of soft tissue sarcomas in these areas; (2) invasion of a major neurovascular bundle warrants a primary amputation; and (3) the addition of radiation therapy is an essential component of the therapy. Modern techniques of radiation, such as hyperfractionation or interstitial implantation, may also decrease the related morbidity.