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Gastric leiomyoma of the antrum intussuscepted into first part of the duodenum is a rare complication. We report here an 80-year-old woman who presented at the Sarawak General Hospital, Kuching, Sarawak, Malaysia with early satiety and epigastric fullness for 3 months. She had no prior medical or surgical history other than an uneventful open cholecystectomy. Upper endoscopy showed a large submucosal mass in the first part of duodenum with pyloric converging gastric folds. Computed tomography scan of the abdomen showed a gastroduodenal intussusception with a 4x6cm mass at the junction between the first and second part of duodenum. Laparoscopic transgastric resection was performed. Histopathological examination of the resected specimen confirmed leiomyoma. She remained well at 43 months follow-up.
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Intususcepción/etiología , Intususcepción/cirugía , Laparoscopía/métodos , Leiomioma/complicaciones , Leiomioma/cirugía , Anciano de 80 o más Años , Femenino , Humanos , Intususcepción/diagnóstico por imagen , Malasia , Neoplasias Gástricas/complicaciones , Resultado del TratamientoRESUMEN
The dynamic-thermal electron-quantum medium finite-difference time-domain (DTEQM-FDTD) method is used for efficient analysis of mode profile in elliptical microcavity. The resonance peak of the elliptical microcavity is studied by varying the length ratio. It is observed that at some length ratios, cavity mode is excited instead of whispering gallery mode. This depicts that mode profiles are length ratio dependent. Through the implementation of the DTEQM-FDTD on graphic processing unit (GPU), the simulation time is reduced by 300 times as compared to the CPU. This leads to an efficient optimization approach to design microcavity lasers for wide range of applications in photonic integrated circuits.
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Le Fort I osteotomies, although they are common procedures, carry a degree of risk of injury to the surrounding structures. Skull base fractures and cerebrospinal fluid rhinorrhoea are amongst the most serious on the list of complications. This is the first reported case of meningoencephalitis post Le Fort I osteotomy, shedding some light on its identification, causes, and management.
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Meningoencefalitis , Fractura Craneal Basilar , Humanos , Craneotomía , Osteotomía , Meningoencefalitis/diagnóstico por imagen , Meningoencefalitis/etiologíaRESUMEN
OBJECTIVE: To identify the optimal dressing for split-thickness skin graft (SSG) donor sites. METHOD: This prospective randomised controlled trial compared two dressings - a new absorbent form of a polyurethane film dressing (Tegaderm Absorbent, 3M) and our standard alginate dressing (Kaltostat, ConvaTec) - on SSG donor sites in 40 patients. Primary outcome measures were: reduced time to full healing; reduced postoperative pain; reduced leakage rates from the dressing. Secondary outcome measures related to acceptability of the dressings to the patient. RESULTS: On removal of the dressings at the first assessment, 79% of the Tegaderm Absorbent donor sites had healed completely, compared with 16% of the Kaltostat ones (p<0.001).A significantly greater median area had healed with Tegaderm Absorbent (100%), when compared with Kaltostat (89%) (p<0.001). Mean time to complete healing was also significantly faster for Tegaderm Absorbent than Kaltostat (14 versus 21 days) (p<0.001). Significantly fewer subjects experienced postoperative pain with Tegaderm Absorbent on both day 1 (21% versus 67%, p=0.006, NNT=3) and day 2 (17% versus 75%, p<0.001, NNT=2). Leakage rates reduced by 48% with Tegaderm Absorbent, with no leakage in the smaller donor sites. Tegaderm Absorbent was significantly easier to apply than Kaltostat (89% versus 27% found it'very easy') as was ease of removal (84% versus 11% found it'very easy') (p<0.0001). Patients found Tegaderm Absorbent dressings significantly more convenient to manage and bathe with. At one month post-surgery, Vancouver scar scores showed thatTegaderm Absorbent donor sites were less red, flatter, softer and less itchy. CONCLUSION: Tegaderm Absorbent provides a significant improvement in terms of donor-site pain, healing and ease of management.
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Alginatos/uso terapéutico , Apósitos Oclusivos/normas , Cuidados de la Piel/instrumentación , Trasplante de Piel/efectos adversos , Cicatrización de Heridas , Adolescente , Adulto , Anciano , Anciano de 80 o más Años , Alginatos/efectos adversos , Niño , Investigación en Enfermería Clínica , Exudados y Transudados , Femenino , Ácido Glucurónico/efectos adversos , Ácido Glucurónico/uso terapéutico , Ácidos Hexurónicos/efectos adversos , Ácidos Hexurónicos/uso terapéutico , Humanos , Masculino , Persona de Mediana Edad , Apósitos Oclusivos/efectos adversos , Aceptación de la Atención de Salud , Poliuretanos , Cuidados Posoperatorios/instrumentación , Cuidados Posoperatorios/enfermería , Estudios Prospectivos , Cuidados de la Piel/enfermería , Muslo/cirugía , Trasplante Autólogo/efectos adversos , Resultado del Tratamiento , VictoriaRESUMEN
The objective of this study was to investigate the prevalence of obesity and its relationship with adverse outcomes in ICU cardiothoracic patients. We performed a retrospective analysis of cardiothoracic patients admitted to The Royal Melbourne Hospital ICU between 2002 and 2014. Eight thousand and sixty-four patients who underwent coronary artery bypass, valve replacement/repair, or both, were divided into six categories of body mass index using World Health Organization criteria. Prevalence of obesity over time in the ICU was measured and compared to prevalence of obesity in the adult Australian population. The association between obesity and adverse postoperative outcomes was then analysed. Obesity is currently 1.2 times more prevalent in the Royal Melbourne Hospital ICU cardiothoracic patients than in the adult Australian population, with 33.5% of patients having a body mass index =30 kg/m(2). Over time, this was relatively constant, but an increasing proportion were morbidly obese. Obesity, but not morbid obesity, was associated with reduced 30-day mortality (odds ratio [OR] 0.41). Both obese and morbidly obese patients had reduced odds of return to theatre for bleeding (OR 0.49 and OR 0.19, respectively), but increased odds of new-onset renal failure (OR 1.62 and OR 3.17, respectively). Morbidly obese patients had double the odds of an ICU stay longer than 14 days (OR 2.05). In summary, a growing proportion of our obese ICU patients are morbidly obese, with a dramatically increased length of ICU stay. This has major implications for resource allocation in the ICU, and may inform modelling of future bed utilisation. Obesity, but not morbid obesity, conferred a mortality benefit.
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Puente de Arteria Coronaria/efectos adversos , Implantación de Prótesis de Válvulas Cardíacas/efectos adversos , Obesidad/epidemiología , Adulto , Anciano , Femenino , Humanos , Masculino , Persona de Mediana Edad , Morbilidad , Obesidad/complicaciones , Prevalencia , Estudios RetrospectivosRESUMEN
Solid tumours comprise, not only malignant cells but also a variety of stromal cells and extracellular matrix proteins. These components interact via an array of signalling pathways to create an adaptable network that may act to promote or suppress cancer progression. To date, the majority of anti-tumour chemotherapeutic agents have principally sought to target the cancer cell. Consequently, resistance develops because of clonal evolution, as a result of selection pressure during tumour expansion. The concept of activating or inhibiting other cell types within the tumour microenvironment is relatively novel and has the advantage of targeting cells which are genetically stable and less likely to develop resistance. This review outlines key players in the stromal tumour microenvironment and discusses potential targeting strategies that may offer therapeutic benefit.
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In this study we reviewed 23 postoperative magnetic resonance (MR) imaging examinations of patients with pituitary macroadenomas to determine if intravenous contrast is of value in this setting. The addition of contrast enhanced images to noncontrast T1-weighted images changed the radiologist's assessment in 4/5 early postoperative examinations and in 0/18 late postoperative examinations. Intravenous contrast is of value in distinguishing residual tumor from packing material on early postoperative MR examinations but is less useful in later postoperative examinations.
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Adenoma/diagnóstico , Medios de Contraste/administración & dosificación , Imagen por Resonancia Magnética/métodos , Cuidados Posoperatorios , Humanos , Neoplasias Hipofisarias/diagnóstico , Estudios Retrospectivos , Método Simple Ciego , Factores de TiempoRESUMEN
The effects of sevoflurane (Sev), isoflurane (Iso), and halothane (Hal) on coronary circulation were studied in 30 dogs with acute coronary arterial stenosis. Regional myocardial blood flow (rMBF) was measured by hydrogen clearance method. There was no significant difference between each anesthetic agent in heart rate, mean arterial pressure, and cardiac output under any anesthesia level. As the inspired concentration of each anesthetic is increased, rMBF decreased significantly and rMBF/rate-pressure-product (RPP) ratio increased in normal area. In Sev and Iso groups, rMBF/RPP ratios were higher than that in Hal group, suggesting luxury perfusion caused by Sev and Iso. In the ischemic area, rMBF was reduced depending on the inspired concentration of each anesthetic agent and transmural maldistribution of blood flow was not observed with any anesthetic agent. Nevertheless the ratio of rMBF in ischemic area to that of normal area was decreased in Sev and Iso groups, but not in Hal group. In this study, neither Sev nor Iso worsened regional myocardial ischemia. However, Sev-induced coronary vasodilation may cause regional myocardial ischemia by redistribution of flow under steal prone condition.
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Anestésicos/farmacología , Circulación Coronaria/efectos de los fármacos , Enfermedad Coronaria/fisiopatología , Éteres/farmacología , Halotano/farmacología , Isoflurano/farmacología , Éteres Metílicos , Animales , Perros , SevofluranoRESUMEN
We investigated perioperative blood gas changes in 26 patients scheduled for surgical correction of femoral neck fracture under epidural anesthesia. Arterial blood gases during spontaneous air respiration were measured eight times during the femoral neck prosthetic replacements (n = 16), and four times during osteosynthesis (n = 10). In the patients who received femoral neck replacements using bone cement (n = 8), arterial oxygen tension decreased significantly four hours after insertion of prosthesis, and did not recover during two postoperative days. In contrast, in the patients who received cementless femoral neck replacements (n = 8), arterial oxygen tension tended to decrease but not significantly, and returned to normal on the second postoperative day. In the patients who received osteosynthesis, arterial oxygen tension did not change. We suspected that the causes of delayed hypoxia in the femoral neck replacements were vascular endothelial cell injury in the lung by free fatty acid originating from fat embolism, and/or microthrombosis resulting from activated coagulation system. Bone cement was thought to intensify fat embolism because of elevated intramedullary pressure in the femur.
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Fracturas del Cuello Femoral/cirugía , Hipoxia/etiología , Complicaciones Posoperatorias , Anciano , Anestesia Epidural , Cementos para Huesos , Femenino , Prótesis de Cadera , Humanos , MasculinoRESUMEN
A 21 day old infant, diagnosed as ASD, VSD, and PDA, was scheduled for an emergency radical operation. After admission, she fell into cardiac failure and was treated with artificial ventilation and infusion of inotropic agents. Anesthesia was induced with fentanyl and maintained with continuous fentanyl infusion and chlorpromazine. Dopamine and dobutamine were administered before she underwent a cor-pulmonary by-pass. At the time of release of aortic clamping, her blood pressure went down and dopamine, dobutamine and isoproterenol were administered. After completion of the cor-pulmonary by-pass, tachy-arrhythmia and hypotension occurred. Digitalis and calcium did not reverse the condition. The thorax was reopened and BP rose. After 15 min, ventricular fibrillation occurred. Defibrillation was carried out, but the heart was arrested. Even with pacing and cardiac massage, cardiac contraction did not resume. However immediately on intravenous administration of PGE1, 40 ng.kg-1.min-1, the heart started to beat. The cause of recovery from cardiac arrest was speculated to be due to reuptake of intracellular Ca2+ by PGE1. We stress therefore, that during and after cor-pulmonary by-pass procedures, PGE1 infusion may be beneficial.
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Alprostadil/uso terapéutico , Procedimientos Quirúrgicos Cardíacos , Urgencias Médicas , Paro Cardíaco/tratamiento farmacológico , Alprostadil/administración & dosificación , Femenino , Humanos , Recién Nacido , Infusiones IntravenosasRESUMEN
The effects of thoracic epidural anesthesia (TEA) on regional myocardial blood flow (RMBF) and hemodynamics were evaluated in open-chest dogs with coronary artery stenosis. In the 6 dogs with pressure-rate quotients (PRQ) of greater than 0.8, TEA caused a significant increase of the ratio of endocardial to epicardial RMBF in the ischemic region and tended to increase the ratio of RMBF in the ischemic to normal area, resulting in improved myocardial ischemia. There was no reduction of myocardial ischemia in the 11 dogs with PRQ of less than 0.8. The hemodynamic effects determine whether TEA is favorable for the ischemic heart or not. It appears that PRQ is useful as an indicator of myocardial oxygen balance during TEA.
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Anestesia Epidural , Hemodinámica/fisiología , Isquemia Miocárdica/fisiopatología , Animales , Gasto Cardíaco/fisiología , Circulación Coronaria/fisiología , Perros , Paro Cardíaco Inducido , Frecuencia Cardíaca/fisiologíaRESUMEN
Aspirin reduces the prevalence of nonfatal myocardial infarction, stroke, and death by 25.0% in high risk group of patients with cardiovascular disease. Previous studies have estimated that about 5.5-56.8% of the population are aspirin resistant. The mechanisms of aspirin resistance (AR) have not been fully understood. We compared the detection methods for AR using traditional platelet aggregometry and VerifyNow system. One hundred and seventy-two coronary artery disease patients who had taken aspirin only or combinations with aspirin and clopidogrel for over 7 days were included. Of the 55 patients with aspirin only, aggregometer detected six AR (10.9%) and VerifyNow identified 10 AR (18.2%) cases. Among 117 patients with combined therapy, none (0.0%) and 10 (8.5%) of AR were detected by aggregometer and VerifyNow, respectively. There were six (3.4%) patients of AR defined by both methods and they all received aspirin monotherapy. Although the correlation between the aggregometry and VerifyNow was low, with defined criteria both methods gave 91.9% agreement to find AR. VerifyNow showed a higher sensitivity to detect AR. Further studies are required to biologically define AR and to alter therapy based on platelet function tests.
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Aspirina/uso terapéutico , Enfermedad de la Arteria Coronaria/tratamiento farmacológico , Resistencia a Medicamentos , Inhibidores de Agregación Plaquetaria/uso terapéutico , Adulto , Anciano , Anciano de 80 o más Años , Técnicas de Laboratorio Clínico/instrumentación , Clopidogrel , Enfermedad de la Arteria Coronaria/clasificación , Femenino , Humanos , Masculino , Persona de Mediana Edad , Pruebas de Función Plaquetaria/métodos , Ticlopidina/análogos & derivados , Ticlopidina/uso terapéuticoRESUMEN
BACKGROUND: The mechanism of platelet recovery after hematopoietic stem cell transplantation and the factors that influence its time-course are not fully understood. Rapid hematopoietic recovery results in a reduction of transplantation-related complications. In the present study, we questioned and analyzed whether there were important factors predicting the speed of platelet engraftment. METHODS: Thirty-seven patients with various hematologic diseases transplanted with allogeneic BM between January 2002 and December 2005 were included. We investigated the differences in mononuclear cell counts (MNC), numbers of infused CD34(+), CD34(+) CD41(+) and CD34(+) CD61(+) cells and phenotypic analysis of homing-associated cell adhesion molecules (CXCR4, CD49d and CD49e). The number of megakaryocytes formed in vitro (colony-forming unit-megakaryocytes; CFU-Mk) was also measured. RESULTS: Median days of ANC >/=0.5x10(9)/L and platelet count >/=20x10(9)/L were 14.8 and 17.3, respectively. The number of infused CD34(+) CD41(+) and CD34(+) CD61(+) cells correlated much better with the time to platelet engraftment than that of infused CD34(+)cells (P<0.05 each). Rapid platelet recovery also occurred in patients receiving both higher homing-associated cell adhesion molecule doses and CFU-Mk (P<0.05 each). DISCUSSION: Rapid platelet recovery has several advantages, including reducing the cost of supportive therapy and reducing the risk of fatal bleeding as a result of severe thrombocytopenia. Our findings suggest that phenotypic and clonogenic assessment of infused progenitor cells can identify patients in whom platelet engraftment is likely to be significantly delayed, and new strategies to overcome related problems might be employed in the very near future.
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Moléculas de Adhesión Celular/metabolismo , Trasplante de Células Madre Hematopoyéticas , Megacariocitos/citología , Megacariocitos/metabolismo , Transfusión de Plaquetas , Células Madre/citología , Adolescente , Adulto , Recuento de Células , Niño , Preescolar , Ensayo de Unidades Formadoras de Colonias , Femenino , Humanos , Inmunofenotipificación , Masculino , Persona de Mediana Edad , Análisis Multivariante , Trasplante HomólogoRESUMEN
The clinical, radiologic and pathological findings in two cases of neuroepithelial cyst of the posterior fossa are described. The first patient was a 43-year-old woman who presented with clumsiness of the hands, gait disturbance and slurring of speech. Magnetic resonance imaging (MRI) revealed a large cystic structure between the cerebellum and the brain stem on the left side, accompanied by compression of the medulla oblongata and displacement of the forth ventricle to the right. The second patient was an 11-month-old boy who presented with progressive bulbar dysfunction. He had previously undergone surgery for myelomeningocele and hydrocephalus associated with Arnold-Chiari type 2 malformation. MRI revealed a large cystic mass isointense with cerebrospinal fluid between the cerebellum and the midbrain, compressing the fourth ventricle and displacing the brain stem to the right. The cases were pathologically similar, the cyst containing a single layer of cuboidal epithelium and rims of neuroglial cells. Immunohistochemical staining was consistent with neuroepithelial cyst. It is important to distinguish this type of cyst from a malignant mass to ensure appropriate treatment and determine the prognosis. In addition, even though neuroepithelial cysts of the posterior fossa are benign, they are often symptomatic because of their mass effect. The second case was unusual because the cyst developed over a period of 2 months, which shows that this type of cyst can develop rapidly. To the authors' knowledge, the association with Arnold-Chiari type 2 malformation has not previously been reported.
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Fosa Craneal Posterior/patología , Quistes/diagnóstico , Adulto , Malformación de Arnold-Chiari/diagnóstico , Fosa Craneal Posterior/diagnóstico por imagen , Fosa Craneal Posterior/cirugía , Quistes/cirugía , Quistes/ultraestructura , Diagnóstico Diferencial , Femenino , Humanos , Lactante , Imagen por Resonancia Magnética , Masculino , Microscopía Electrónica , Tomografía Computarizada por Rayos XRESUMEN
The authors report a case of tracheobronchomegaly in a 62-year-old man with chronic expiratory cough. Computed tomography showed dilatation of the trachea on inspiration and complete collapse of the trachea and the proximal bronchi on full expiration. The authors discuss the importance of the collapse on expiration as the cause of the patient's symptoms.
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Traqueobroncomegalia/diagnóstico por imagen , Broncografía , Humanos , Masculino , Persona de Mediana Edad , Tomografía Computarizada por Rayos X , Tráquea/diagnóstico por imagenRESUMEN
PURPOSE: To report the long-term follow-up of previously reported cases of salvaging failing or failed in situ bypass grafts using endovascular techniques, to include previously unreported cases, and to include the results of thrombolysis for the salvage of occluded in situ venous bypass grafts. MATERIALS AND METHODS: Between 1985 and 1995, 352 patients underwent distal bypass via the in situ saphenous vein. Seventy-three of these patients underwent endovascular interventions for (i) graft stenoses (65 lesions in 40 patients) treated by balloon angioplasty (PTA), (ii) AV residual fistulas to veins (AVF) (23 patients) occluded by coil embolotherapy, (iii) graft occlusion (21 occluded grafts in 19 patients) treated by catheter-directed high-dose thrombolytic infusion and PTA or surgical revision of uncovered stenoses, and (iv) retained valve leaflets causing stenoses (five patients) treated by valvectomy and/or PTA. Cumulative patency rates were determined by the Kaplan-Meier method. Twenty-nine of 73 patients had been previously reported by the authors. RESULTS: PTA was successful in 39 of 40 patients, cumulative patency after bypass PTA was 0.79 (SE +/- 0.07) for 12 months and 0.63 (SE +/- 0.12) for 5 years. The only complication of PTA was a graft anastomotic disruption that was successfully treated by surgery. Longer lesions and lesions requiring repeated PTA were more likely to restenose. For thrombolysis, there were 13 of 19 successful infusions and five delayed occlusions. The cumulative patency for both 12 months and 5 years was 0.43 (SE +/- 0.12). AVF embolization was successful in 21 of 23 patients. Cumulative patency for 12 months and 5 years was 0.87 (SE +/- 0.07) and 0.81 (SE +/- 0.09), respectively. Five successful valvectomy procedures were performed by stripping residual valves with endocardial forceps. CONCLUSION: In experienced hands, PTA and AVF embolization can be performed on failing in situ saphenous vein bypass grafts with good long-term patency. Thrombolysis results were less favorable but can prolong patency of grafts.
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Angioplastia de Balón/métodos , Embolización Terapéutica/métodos , Oclusión de Injerto Vascular/terapia , Vena Safena , Terapia Trombolítica/métodos , Anciano , Anciano de 80 o más Años , Anastomosis Quirúrgica/efectos adversos , Angiografía , Implantación de Prótesis Vascular/efectos adversos , Femenino , Arteria Femoral/diagnóstico por imagen , Arteria Femoral/cirugía , Fibrinolíticos/administración & dosificación , Estudios de Seguimiento , Oclusión de Injerto Vascular/diagnóstico por imagen , Humanos , Inyecciones Intraarteriales , Isquemia/diagnóstico por imagen , Isquemia/cirugía , Pierna/irrigación sanguínea , Masculino , Persona de Mediana Edad , Arteria Poplítea/diagnóstico por imagen , Arteria Poplítea/cirugía , Falla de Prótesis , Estudios Retrospectivos , Vena Safena/trasplanteRESUMEN
OBJECTIVE: To review indications, contraindications, and risks of using magnetic resonance imaging (MRI) in order to help primary care physicians refer patients appropriately for MRI, screen for contraindications to using MRI, and educate patients about MRI. QUALITY OF EVIDENCE: Recommendations are based on classic textbooks, the policies of our MRI group, and a literature search using MEDLINE with the MeSH headings magnetic resonance imaging, brain, musculoskeletal, and spine. The search was limited to human, English-language, and review articles. Evidence in favour of using MRI for imaging the head, spine, and joints is well established. For cardiac, abdominal, and pelvic conditions, MRI has been shown useful for certain indications, usually to complement other modalities. MAIN MESSAGE: For demonstrating soft tissue conditions, MRI is better than computed tomography (CT), but CT shows bone and acute bleeding better. Therefore, patients with trauma or suspected intracranial bleeding should have CT. Tumours, congenital abnormalities, vascular structures, and the cervical or thoracic spine show better on MRI. Either modality can be used for lower back pain. Cardiac, abdominal, and pelvic abnormalities should be imaged with ultrasound or CT before MRI. Contraindications for MRI are mainly metallic implants or shrapnel, severe claustrophobia, or obesity. CONCLUSIONS: With the increasing availability of MRI scanners in Canada, better understanding of the indications, contraindications, and risks will be helpful for family physicians and their patients.
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Imagen por Resonancia Magnética , Adulto , Enfermedades Óseas/diagnóstico , Enfermedades Óseas/diagnóstico por imagen , Hemorragia Cerebral/diagnóstico , Hemorragia Cerebral/diagnóstico por imagen , Anomalías Congénitas/diagnóstico , Anomalías Congénitas/diagnóstico por imagen , Contraindicaciones , Costos y Análisis de Costo , Medicina Familiar y Comunitaria , Cardiopatías/diagnóstico , Cardiopatías/diagnóstico por imagen , Humanos , Dolor de la Región Lumbar/diagnóstico , Dolor de la Región Lumbar/diagnóstico por imagen , Angiografía por Resonancia Magnética , Imagen por Resonancia Magnética/economía , Masculino , Neoplasias/diagnóstico , Neoplasias/diagnóstico por imagen , Educación del Paciente como Asunto , Selección de Paciente , Enfermedades de la Columna Vertebral/diagnóstico , Enfermedades de la Columna Vertebral/diagnóstico por imagen , Tomografía Computarizada por Rayos X , UltrasonografíaRESUMEN
Cardiac rhabdomyomas are associated with tuberous sclerosis, but their identification in utero is uncommon. The authors report a case of multiple cardiac masses discovered in utero by prenatal ultrasonography at about 30 weeks gestational age. Follow-up included neonatal echocardiography, ultrasonography and computed tomography of the head. The differential diagnosis of echogenic intracardiac masses, as well as their management, is discussed.