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1.
Mymensingh Med J ; 31(3): 861-868, 2022 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-35780375

RESUMO

The tendo achilles is one of most important tendon in human body which often injured through direct trauma or indirect stress on a weakened tendon. Longer the duration after injury the injured parts likely to move apart, fibrosis and degeneration leading to difficulty in repair or reconstruction. Usually a phase of 4 weeks or more without specific treatment is regarded as chronic or neglected rupture. Different authors described many management protocols about the tendo achilles rupture but there is no procedure of choice for neglected rupture with long gap. Prospective case series of 21 patients of neglected tendo achilles rupture with long gap treated with flexor hallucis longus tendon (FHLT) transfer was taken for study from January 2019 to December 2020 in Mymensingh Medical College Hospital, Bangladesh. Average age of patients was 39.47 years with range 22-65 years. Fifteen (15) cases of traumatic rupture in this study with average age 32.66 years and pathologic 6 cases with average age 56.5 years were recorded. We grafted FHLT from channel by incising Henry's knot. Krackow et al.'s technique was followed for tendon mobilization and bone fixation. We made procedure simpler and cheaper; instead of using interference screw the sutured tendon pulled through the heel and anchored over rubber tube or button by Cole method. Post-operative complications were less with one patient with superficial infection which eventually recovered 3 cases of mild pain and 2 cases of numbness. Questionnaire for surgical outcome measure are satisfactory in 19 patients (90.47%). Final follow up AOFAS score at 6 month (91.61±5.41) was highly significant (p<0.001) in comparison to preoperative score (38.71±9.78). These are comparable to other study. Above mentioned scores indicate the reliability of the surgical system. But our study is a prospective case series with minimum cases. To establish the best procedure for neglected tendo achilles rupture with long gap we recommend further study with larger group and Randomized Controlled Trial (RCT) study among different procedure.


Assuntos
Tendão do Calcâneo , Procedimentos de Cirurgia Plástica , Traumatismos dos Tendões , Tendão do Calcâneo/lesões , Tendão do Calcâneo/cirurgia , Adulto , Idoso , Humanos , Pessoa de Meia-Idade , Procedimentos de Cirurgia Plástica/métodos , Ruptura/cirurgia , Traumatismos dos Tendões/cirurgia , Transferência Tendinosa/métodos , Adulto Jovem
2.
Mymensingh Med J ; 30(3): 657-665, 2021 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-34226452

RESUMO

Intramedullary nailing is a pillar in the treatment of femoral shaft fractures. But it is not possible in all cases especially in comminuted fractures. This study has been designed to explain the importance of Minimally Invasive Plate Osteosynthesis (MIPO) with the locking plate in the treatment of comminuted Femoral Shaft Fracture. Twenty (20) such patients were treated by MIPO and analysis has been done in this study to get fruitful result and to find out the effectiveness of this procedure who were admitted at Mymensingh Medical College Hospital, Mymensingh, a tertiary level hospital of Bangladesh from February 2018 to January 2019. Mean age of the patients were 49.20±14.41 years. Based on AO classification, there were 4, 8 and 8 patients belong to type A, B and C respectively. The union period for all the patients was in between 12 to 14 weeks. The mean union period was 12.90±1.997 weeks. Mean follow up period was 19.70±2.77 weeks. Mean full weight bearing period was 16.50±1.10 weeks. In Thoresen scoring system excellent result was 9(45%), good result was 10(20%) and fair result was 01(5%). Mal-alignment happened in two cases. However, delayed union and broken screws were found in two cases each of which was treated accordingly. Comminuted Femoral shaft fracture with MIPO procedure is more effective treatment than intramedullary nailing. Furthermore, mal-alignment is the basic complexity that must be taken away intraoperatively.


Assuntos
Fraturas do Fêmur , Fraturas Cominutivas , Adulto , Bangladesh , Placas Ósseas , Fraturas do Fêmur/diagnóstico por imagem , Fraturas do Fêmur/cirurgia , Fixação Interna de Fraturas , Fraturas Cominutivas/diagnóstico por imagem , Fraturas Cominutivas/cirurgia , Humanos , Pessoa de Meia-Idade , Procedimentos Cirúrgicos Minimamente Invasivos , Resultado do Tratamento
3.
Org Biomol Chem ; 16(24): 4424-4428, 2018 06 20.
Artigo em Inglês | MEDLINE | ID: mdl-29498732

RESUMO

We report a series of novel methylene-linked bis-phenylbenzimidazoles intercalators that stabilize telomeric DNA/RNA hybrid (tDRH) structures by up to 7.2 °C at a 1 µM ligand concentration while having negligible affinity for DNA/DNA duplexes, although with a low affinity for quadruplex DNA. We have used molecular modelling studies to rationalize this selectivity, concluding that the methylene spacer between the terminal benzimidazole and phenylene moieties plays a key role in facilitating the bis-intercalating process. This scaffold may be used to develop chemical tools or new therapeutics to selectively target the telomeric DNA/RNA duplex without affecting normal genomic DNA.


Assuntos
Benzimidazóis/química , DNA/química , Substâncias Intercalantes/química , RNA/química , Telômero/química , Benzimidazóis/síntese química , Linhagem Celular Tumoral , Humanos , Substâncias Intercalantes/síntese química , Ligantes , Simulação de Dinâmica Molecular , Estrutura Molecular , Hibridização de Ácido Nucleico , Relação Estrutura-Atividade
4.
Mymensingh Med J ; 23(1): 69-74, 2014 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-24584376

RESUMO

Hirschsprung's disease (HD) is developmental disorder of the enteric nervous system. Diagnosis can be confirmed by rectal biopsy. The surgical management of HD includes so many procedures. The purpose of this study was to evaluate the out come of single-stage transanal endorectal pull-through operation for short segment HD in neonates and infants. This prospective study was carried out in the Department of Pediatric Surgery, Dhaka Shishu (Children) Hospital, Dhaka, Bangladesh during the period from January 2004 to December 2009. The study included neonates & infants (age 1 day to 1 year) of both sex, who were clinically suspected and biopsy proven HD with barium enema suggesting rectosigmoid HD. We excluded patients with short segment HD who had associated anomalies, and with hugely dilated proximal colon, operated cases with less than 6 months' follow up. During study period, single-stage transanal endorectal pull through (TEP) operation done in 68 neonates and infants patients (8 excluded) of short segment HD. The mean operative time, postoperative hospital stay, followed up time were 120 minutes, 7.94 days and 12 months respectively. Transeverse colostomy was needed in 4 patients because of anastomotic leakage and they were complicated with anastomotic stenosis, however managed by progressive dilatation. Overall parents' satisfaction was achieved. Single-stage primary transnanl endorectal pull-through for short segment HD is feasible in neonates and infants. It preserves all the advantages of minimally invasive surgery. TEP is a better option in terms of comfort, operative success, postoperative morbidity, cosmetic appearance and parents' satisfaction.


Assuntos
Procedimentos Cirúrgicos do Sistema Digestório/métodos , Doença de Hirschsprung/cirurgia , Canal Anal/cirurgia , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Estudos Prospectivos , Reto/cirurgia
5.
Mymensingh Med J ; 22(2): 232-6, 2013 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-23715341

RESUMO

Inguinal hernia repair is one of the most frequently performed surgical procedures in infants and young children. This prospective comparative study was conducted with initial experience in the department of pediatric surgery, Dhaka Shishu (children) hospital during the period of July 2007 to August 2008. We enrolled 62 children undergoing surgery for inguinal hernia, of which 30 underwent laparoscopic procedure (bilateral in 21, unilateral 9) and 32 open procedures (bilateral in 5, unilateral in 27). Mean±SD patient age was 5.92±2.11 months in laparoscopic group and 6.63±2.64 months in open group (p=0.264), 3 months to 5 years in both groups. Patients were studied under variables of operative time, duration of postoperative hospital stay & post operative complications. During laparoscopy a contralateral patent processus vaginalis of ≥2cm was noted and repaired peroperatively in 18 out of 27 children (66%), who were initially diagnosed as unilateral hernia. For unilateral repair mean±SD operative time was significantly longer in Group A (62.63±52.75) minutes compares to the Group B (29.37±9.40), p<0.001. On the contrary, for bilateral repair Mean±SD operative time was comparable between the two groups (64.65±49.70) minutes for laparoscopy & (35.65±11.53 minutes) for open herniotomy & P=0.01, that was not remarkably significant. The mean±SD post operative length of hospital stay (in hours) 36.00±32.7 hours in Group A compared to 29.97±11.82 hours in Group B which was not statically significant (p=0.342). The mean±SD follow up was 24.5±10.5 months in laparoscopic group (Group A) & 22.5±10.5 months in open group (Group B), p=0.251. Regarding post operative complication, in this study, contra lateral metachronous inguinal hernia (CMIH) manifested in none of the patient out of 27 (total unilateral repaired number) patients in laparoscopic group but contrary to this in open group 2 patients out of 27 had developed CMIH & p value was <0.05, which is statistically significant. There were 2 cases of scrotal hydrocele out of 30, observed in Group A whereas 1 case out of 32 in Group B, p=0.49, which was statistically insignificant. The scrotal hydrocele was lasted only for 2 days & resolved spontaneously. About recurrence after operation, our study noted that, 1 case (3.3%) out of 30 in laparoscopic group and 2 cases (6%) out of 32 in open surgery group had developed recurrent inguinal hernia in about one year follow up where p value was 0.459, & it was statistically insignificant. In this study, none of the patient had developed post operative testicular atrophy (due to any vas or vascular injury) or testicular ascend. So, overall this study result implies that, Laparoscopic herniotomy might be a safe and effective option as open herniotomy for the treatment of inguinal hernia in children but which one would be superior or best option it requires a large series of randomized trial.


Assuntos
Hérnia Inguinal/cirurgia , Herniorrafia/métodos , Laparoscopia , Pré-Escolar , Feminino , Humanos , Lactente , Tempo de Internação/estatística & dados numéricos , Masculino , Duração da Cirurgia , Complicações Pós-Operatórias , Estudos Prospectivos , Resultado do Tratamento
6.
Mymensingh Med J ; 21(3): 430-4, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-22828538

RESUMO

This prospective comparative study was conducted with an initial experience in the Department of Pediatric Surgery, Dhaka Shishu (Children) Hospital during the period of December 2007 to January 2009, with the infants of 2-12 weeks age, diagnosed as Hypertrophic pyloric stenosis. Patients selection was done by simple random technique by means of lottery. For open pyloromyotomy conventional method & for laparoscopic pyloromyotomy three trocher techniques was applied. In this study, among 60 cases with infantile hypertrophic pyloric stenosis, 30 cases were finally selected for analysis irrespectively both in laparoscopic (Group A) & in open pyloromyotomy (Group B) group. Patients were studied under variables of operative time, required time of full feeds after operation, post operative hospital stay & both per and post operative complications. Regarding operative time, in Group A, mean±SD operating time (in minutes) was 61.59±51.73 whereas in Group B it was 28.33±8.40 & P value was 0.001. The result was statistically significant. The mean±SD time (in hours) of full feeds (ad libitum) was 35.00±31.70 hours in Group A compared to 28.95±10.99 hours in Group B and P value was found 0.342ns which was not statistically significant. On study of total length (in days) of post operative hospital stay, mean±SD was 3.09±2.25 & 2.58±1.15days in laparoscopic group & open pyloromyotomy group respectively. The p value was 0.355ns, which was statistically insignificant. Again, on study of complications, per operatively 6(19.5%) patients had developed haemorrage, 1(3.33%) had mucosal perforation & 4(13.36%) had developed duodenal serosal injury in laparoscopic group whereas only 1(3.33%) patient in open pyloromyotomy group had nothing else except simple hemorrhage. The p value (0.051ns) was also statistically insignificant. In regard to post operative complications, 2(6.6%) patients had developed wound hematoma, 2(6.6%) had wound infection, 1(3.33 %) had developed wound dehiscence and incisional hernia respectively in Group A. But in group B there was no subject with any complication. This result was also statistically insignificant. So, the overall study results denote that, laparoscopic pyloromyotomy would not be considered as a superior procedure or as safe as that of traditional open pyloromyotomy for the beginners.


Assuntos
Laparoscopia/métodos , Estenose Pilórica Hipertrófica/cirurgia , Piloro/cirurgia , Humanos , Lactente , Estudos Prospectivos
7.
Mymensingh Med J ; 21(2): 333-6, 2012 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-22561780

RESUMO

Intussusception secondary to Primary Non-Hodgkin lymphoma presenting colo-colic variety is a very rare clinical entity and sometimes causing diagnostic dilemma due to non-specific, varied & wide spectrum presentation. In this study, a 9 years female child presented with recurrent, intermittent, colicky abdominal pain with occasional bilious vomiting, along with a left illiac fossa swelling & occasional per rectal bleeding and constipation for 3 months was clinically diagnosed as a case of recurrent obstructing intussusception. At laparotomy, a colo-colic intussusception with prolapsed intussusception was marked & finally on histopathology, she was diagnosed as a case of colo-colic variety of intussusception due to primary Non-Hodgkin lymphoma- a pathological lead point in mid transverse colon. After uneventful recovery of post operative period she was treated with combination chemotherapy accordingly & follow up was given up to 5 years. She had been found alright without any recurrence or organ involvement. The study focused on the avoidance of unusual delay in diagnosis as well as in proper management of rare variants of intussusception.


Assuntos
Doenças do Colo/etiologia , Intussuscepção/etiologia , Linfoma não Hodgkin/complicações , Criança , Doenças do Colo/diagnóstico , Doenças do Colo/cirurgia , Feminino , Humanos , Intussuscepção/diagnóstico , Intussuscepção/cirurgia , Linfoma não Hodgkin/tratamento farmacológico
8.
Mymensingh Med J ; 20(2): 192-6, 2011 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-21522086

RESUMO

To see accuracy of ultrasound scan to detect patent processus vaginalis in padiatric patient. We investigated the presence of contralateral patent processus vaginalis (CPPV) by Ultrasound scan (US) in children with clinically diagnosed unilateral inguinal hernia. Thirty patents (17 boys and 13 Girls) with unilateral inguinal hernia underwent US examination using a 7.5 MHZ transducer. If a CPPV was visible as a hydrocele (inflow of peritoneal fluid) in to a processus vaginalis on straining, then US scanning was performed while the patient was at rest and while inducing straining by standing, coughing and or crying. A groin with hydrocele in the inguinal canal on straining was diagnosed as a CPPV and was explored bilaterally through surgery. The US findings were compared with surgical results. In 30 patients, 12 cases were diagnosed by US as patients with a CPPV, these patients underwent bilateral surgery. Eleven of 12 Cases were confirmed surgically as CPPV. From the findings of the present study it could be concluded that a PPV could be correctly detected by US in pediatric patients with the accuracy of 91.67%. US is a non invasive and accurate method for evaluating the presence of a PPV. Preoperative diagnosis of CPPV is important to remove the need for a second operation with patients presenting with unilateral inguinal hernia.


Assuntos
Hérnia Inguinal/diagnóstico por imagem , Doenças Peritoneais/diagnóstico por imagem , Hidrocele Testicular/diagnóstico por imagem , Criança , Pré-Escolar , Feminino , Humanos , Masculino , Sensibilidade e Especificidade , Ultrassonografia
9.
Mymensingh Med J ; 19(3): 348-52, 2010 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-20639825

RESUMO

This prospective comparative study was conducted in the department of Pediatric Surgery, Dhaka Shishu (children) Hospital during the period of June 2007 to September 2008 with the children of <12 years, diagnosed as acute Appendicitis. Patient selection was done by simple random technique by means of lottery. For open Appendectomy (OA) conventional method & for Laparoscopic Appendectomy (LA) 3 trocher technique was applied. Data was analyzed with the help of SPSS version 10. In this study 60 cases with acute Appendicitis including both gender were studied by two groups, group-A include 30 cases for laparoscopic and group-B include 30 cases for open appendectomy. Postoperative pain was assessed in both groups by using FLACC scale and compared at 1st 6-hours, 24 hours, 72 hours, 96 hours & at day 7. At 1st 6-hours, most of the children 24(80%) of group A had moderate pain whereas 17(56.7%) children of group B had severe pain (p<0.001). At 24 hours most of the patient 17(56.7%) of group A had mild pain compared to 27 (90%) patients of group B had moderate pain (p<0.0001). At 48 hours in group A most of the children 23(76.7%) had mild pain compared to moderate pain in 18(60%) children of group B (p<0.0001). Subsequently at 72 hours and at 96 hours most of the patients of LA group were free of pain compared to OA group. At final follow-up on day 7, 29(96.7%) children of group A had no pain compared to 26(86.7%) of group B. Regarding analgesics requirement both qualitative & quantitative requirements of analgesics were less in LA group than OA group. About post operative wound infection in group A only 1(3.3%) case had developed post operative wound infection whereas in group B 7(23.3 %) cases had. The mean (+/-SD) of post operative length of hospital stay was 52.00+/-11.62 (range 48-96) hours for group A and 76.00+/-12.74 (range 48-96) hours for group B children (p<0.001). Laparoscopic Appendectomy is more effective, preferable & superior procedure than that of open Appendectomy to reduce the post operative morbidity in children undergone appendectomy for acute appendicitis.


Assuntos
Apendicectomia/métodos , Laparoscopia , Complicações Pós-Operatórias/epidemiologia , Bangladesh/epidemiologia , Criança , Pré-Escolar , Feminino , Humanos , Tempo de Internação , Masculino , Dor Pós-Operatória/epidemiologia , Estudos Prospectivos , Infecção da Ferida Cirúrgica/epidemiologia
10.
Mymensingh Med J ; 15(2): 128-30, 2006 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-16878090

RESUMO

The urogenital tract is the most severe and common site of associated defects in anorectal malformations (ARM). Urogenital anomalies and their complications significantly increase the morbidity in these children after the ARM is corrected. The purpose of this study was to estimate the incidence of different types of urogenital anomalies with various types of anorectal malformations and to discuss the possible management and outcome. A retrospective study of patients with ARM and associated urogenital abnormalities admitted in the department of paediatric surgery of Sylhet MAG Osmani Medical College Hospital between 1998 and 2002 was undertaken. A total of 155 patients with Anorectal malformations were admitted of which 47 (30.32%) patients had associated anomalies involving other systems. Urogenital abnormalities were found in 25 (16.13%) patients. Patients of Anorectal malformations with urogenital abnormalities require careful assessment and well-timed intervention to minimize the morbidity.


Assuntos
Canal Anal/anormalidades , Anormalidades do Sistema Digestório/epidemiologia , Reto/anormalidades , Anormalidades Urogenitais/epidemiologia , Bangladesh/epidemiologia , Criança , Feminino , Humanos , Incidência , Masculino , Estudos Retrospectivos
11.
Int J Radiat Oncol Biol Phys ; 49(5): 1469-73, 2001 Apr 01.
Artigo em Inglês | MEDLINE | ID: mdl-11286855

RESUMO

PURPOSE: To investigate the effectiveness of a simple and practical shielding device to reduce fetal dose for a patient undergoing radiation therapy of nasopharyngeal carcinoma. METHODS AND MATERIALS: Using 5-cm-thick lead bricks and a heavy-duty steel cart, a 50 x 50-cm portable shield was designed and fabricated to reduce fetal dose due to collimator scatter and head leakage radiation. With the gantry at 90 degrees /270 degrees the shield can be easily positioned between the machine head and the fetus to reduce peripheral dose. Dose measurements for 6-MV X-rays and 9-MeV electrons have been made, utilizing a Rando phantom, to quantify the effect of the shield. RESULTS: Measurements show that the peripheral dose to the fetus can be reduced by 60% when the simple shielding device is used.


Assuntos
Carcinoma de Células Escamosas/radioterapia , Feto , Neoplasias Nasofaríngeas/radioterapia , Complicações Neoplásicas na Gravidez/radioterapia , Proteção Radiológica/instrumentação , Desenho de Equipamento , Feminino , Humanos , Imagens de Fantasmas , Fenômenos Físicos , Física , Gravidez , Dosagem Radioterapêutica , Espalhamento de Radiação
12.
Med Phys ; 22(12): 2075-81, 1995 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-8746713

RESUMO

Transmission through a beam-modifying absorber consists of attenuated primary beam and scattered radiation generated by the absorber. The primary component of the transmitted beam is characterized by the narrow beam attenuation coefficient which depends upon the energy of the beam and type of the absorber. In addition to beam energy and absorber material, the scatter component also depends on field size, thickness and shape of the absorber, location of the absorber with respect to the source, and the point of calculation. Based upon Compton first-scatter, a method has been developed to calculate effective broad beam transmission through any arbitrarily shaped absorber with variable thickness for any points on and off the central axis. The method requires predetermined narrow beam attenuation coefficients as a function of thickness. Transmission calculations for various absorbers such as wedges and attenuators were performed for cobalt-60 and 6-MV beams and were compared with measured data. For a cobalt-60 beam, the measured transmission fraction through a 1.33-cm-thick absorber (alloy, consisting of 55% bismuth and 45% lead) for a field size of 24 x 24 cm2 is 17% higher than the calculated value using a narrow beam attenuation coefficient. Also, for the same absorber, measured central axis transmission is as much as 3.6% higher compared to off-axis locations. The measured transmission fraction through a 1.33-cm absorber was found to differ by as much as 13% and 14% for Cobalt-60 and 6 MV, respectively, as the chamber-to-source distance was varied from 70 to 110 cm. The agreement between calculated and measured values is within 0.5% for both energies whereas conventional narrow beam calculations would have yielded errors of 18% and 19%, respectively. Similar agreement was obtained when comparing calculated and measured wedge factors as a function of field size, with the maximum deviation being 0.7%. Measured scattered doses, due to an attenuator covering part of a beam, show a maximum for a thickness of approximately one mean-free path. This is also predicted by calculations with an agreement of 0.3%.


Assuntos
Radioterapia de Alta Energia , Espalhamento de Radiação , Fenômenos Biofísicos , Biofísica , Radioisótopos de Cobalto , Humanos , Modelos Teóricos , Fótons , Tecnologia Radiológica
13.
Med Phys ; 20(1): 187-91, 1993.
Artigo em Inglês | MEDLINE | ID: mdl-8455498

RESUMO

A simple method has been developed to reproduce depth ionization data of electron beams for energy determination. The method utilizes a simple set of equipment, a combination of a specially designed wedge-shaped polystyrene phantom and a linear array of detectors, to collect the necessary data. The wedge-shaped phantom provides varying depths to various detectors in the array. The ionization readings received from the detectors were corrected for off-axis ratio and plotted against corresponding ray-line depths to produce depth ionization curves. The instrument setup was fast and simple. The relevant data, for a high-energy linear accelerator with multiple electron energies, were collected in minutes. The depths of 80% and 50% ionization determined by this method were found to differ by 2 and 3 mm, respectively, at the most, with those determined by a conventional method.


Assuntos
Radioterapia de Alta Energia/normas , Fenômenos Biofísicos , Biofísica , Elétrons , Estudos de Avaliação como Assunto , Humanos , Modelos Estruturais , Controle de Qualidade , Dosagem Radioterapêutica , Radioterapia de Alta Energia/estatística & dados numéricos
14.
Med Phys ; 17(4): 710-4, 1990.
Artigo em Inglês | MEDLINE | ID: mdl-2120560

RESUMO

Electron-beam characteristics of a Philips SL25 linear accelerator have been studied. Central-axis percentage depth doses, cross-beam profiles and beam output factors of 6-, 10-, and 20-MeV beams, selected from the available energy range of 4 to 22 MeV, are reported in this paper. The main thrust of this work is to determine the systematic variation of beam characteristics, especially the output factor, with standard cone sizes and cerrobend beam-shaping cutouts down to a field size of 2 X 2 cm Output factors for the standard cones (open field) are energy dependent in a complex manner, increasing with the cone size for the 6-MeV beam whereas decreasing for 10- and 20-MeV beams. The output factor falls below unity at lower energies (6 and 10 MeV) for fields with at least one side smaller than 6 cm, and stays nearly constant for the 20-MeV beam. Measured output factors of small fields are least squares fitted by a second-order polynomial function. Output factors for small rectangular fields have been derived from the one-dimensional and square-root formulas, and the equivalent-square method. Only the one-dimensional formula predicts the measured output factors of highly elongated fields to within +/- 1% experimental uncertainties. Different cones with the same size electron cutout show a varied dose response, primarily due to variation in scattered electron contamination from the cones.


Assuntos
Elétrons , Aceleradores de Partículas , Dosagem Radioterapêutica , Radioterapia de Alta Energia , Humanos , Tecnologia Radiológica
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