Contact Lens Case Study Analysis

Contact Lens Case Study Analysis Contact lenses Contact lenses are a suitable substitute for correcting vision in a number of scenarios. There are hundreds of different contact lens types out there in today’s market with the figure growing extensively every year. With the advancement of research and technology, manufactures are always attempting to better their own product lines to suit a variety of needs a person may have, whilst also attempting to 1-up their competitors. The patient we are attempting to fit with lenses has never worn them before so as far as options go, we are open to explore different lens types and materials amounting to 100s of different combinations. She is a nurse who works long shifts in a hospital and desires fulltime CL wear of up to 12 hours a day, 7 days a week. To do this, we must assess each aspect of the test and result and cater lens choice to match intended wear time and to also correct her vision for both distance and near. The prescription that we have been presented with is a high myopic prescription so we need to compensate for the change in distance as the contact lens will sit on the cornea and not 12mm away. The compensated contact lens prescription equates to: Soft lenses come in many forms and for this patient, a silicone hydrogel (SiH) lens material would be the one to choose due to its high oxygen transmission (Dk/T) levels, much higher than hydrogel, like the SiH AirOptix Aqua, [Dk 138, 33% water, 8.6 base curve, 14.mm diameter, (AIR OPTIX ® AQUA Contact Lens, no date)] lens vs. the Frequency 55, [Dk 21, 55% water, (Frequency 55 aspheric | CooperVision UK, no date)] hydrogel lens. The Dk/T should be at a level where enough oxygen is passing through to the cornea, avoiding hypoxic conditions and preventing neovascularisation and oedema of the cornea which can lead to permanent corneal damage. SiH lenses however are not as comfortable as regular hydrogel materials due to the rubbery nature of the lens, and also the lenses hold less moisture compared to regular hydrogel. Silicone is not a wettable material so corneal hydration is an issue. (Sweeney, 2004, pp. 3 – 3). Manufacturers combat this by incorporating technology into the lens such as AquaGen found in Clarity 1 day toric [Dk 57, Water 56%, 8.6mm base curve, 14.3mm diameter (SAUFLON, no date)] .This allows the lens to stay hydrated and increase overall comfort wear-time, something extremely important for this nurse. Soft lenses drape over the cornea and range between 13.8mm-14.5mm sizes in order to cater for the patient’s measurements. A well fitted soft lens will ensure that the lens has corneal coverage in all directions of gaze. The lens should have movement of at least 1/4mm when blinking, not more because of the variable vision it will cause, or less as it will cause discomfort and should also allow adequate exchange of tears behind the lens to allow debris removal (Gasson and Morris, 2010, pp. 227-227). Rigid gas permeable (RGP) lenses are much more complex to fit than soft lenses They are tailor made to the patient’s prescription and measurements such as horizontal iris diameter (HVID) and pupil size. RGPs are smaller than soft lenses and smaller in diameter than the cornea itself, with diameters ranging from 8mm to 11mm. RGPs float on the tear film and can create a lens made out of tears. (Gasson and Morris, 2010, pp. 137 – 139) Practitioners need to take this tear lens into account as it can negate the need for toric lenses or require prescription adjustments through over-refraction (Gasson and Morris, 2010, pp. 137 – 139). RGPs offer superior clarity than their softer counterparts and are much more durable and longer lasting, however are mostly overlooked in modern times (outside of therapeutics) due to the patient’s impatience of adapting to the initial uncomfortable fitting. RGPs are also easier to lose as they can pop out of the eye much easier and are more difficult to completely cleanse, something important for this nurse considering her working environment. Assessing her slit-lamp examination results such as her tear break up time (TBUT) and tear prism, I would be looking at a lens that plentiful hydration to the cornea. This is because her TBUT of less than 10 seconds at 7 seconds and her tear prism of 0.2 mm indicate that she suffers from dry eyes (Dryeyesmedical, no date). Having dry eyes and not addressing the issue will result in significantly reduced wear time due to great increase in discomfort. High water content lenses; whilst more comfortable than most other lenses at first, deteriorate in comfort as the day progresses due to evaporation (Efron, 2012, pp. 87 – 87). These lenses then proceed to draw water from the next available source being the tear film through osmosis will cause discomfort for this nurse as she does suffer from dry eyes, reducing wear time considerably. Her TBUT and tear prism will influence the lens choice as she does intend full time lens wear, such as a SiH lens like the Acuvue Oasys toric lens [Dk 147, Water 38%, 8.4mm base curve, 14.3mm diameter, (JJvisioncare, no date)] or a RGP lens. The astigmatism present in her prescription will necessitate toric lenses which allow practitioners to correct astigmatism. Most popular toric lenses available on the market such as the Biofinity toric lens corrects astigmatism only up to a maximum of -2.25DC and the axis is only correctable to the nearest 10 ° meaning that contact lens practitioners must sometimes compromise the vision slightly when the prescription is unavailable in exact power and axis specifications such as this nurse (Ruben and editor., 1978, pp. 212 – 213), where an axis of 180 ° would need to be given for both lenses. An ideal lens for this nurse such as the Clarity 1day toric employs prism ballast which places 1-1.5Δ of base down prism at the base of the lens for stability. Stability of the lens reduces lens rotation and ensures toric lenses stay on axis. This does increase lens thickness and causes a reduction of Dk/T at the base of the lens, increasing risk of hypoxia at the zone (Efron, 2012, pp. 221 – 221). Acuvue Oasys toric lenses employ peri ballast aka accelerated stabilisation designs which have 4 stability zones. This design is claimed to provide more rapid settling on the cornea; within 1 minute, and achieve correct orientation within 5 ° of the anticipated position in 90% of cases (Gasson and Morris, 2010, pp. 266 – 266) Prism Peri ballast designs (Methods of Stabilisation | Optometry by Catherine Care, no date) RGP lenses would be a serious candidate due to her corneal astigmatism (K) readings gained from the keratometer. Her measurements gained were: RE: [emailprotected] [emailprotected] LE: [emailprotected] [emailprotected] Every 0.05 of difference between the 2 readings gained by each eye corresponds to 0.25DC, so comparing her corneal astigmatism to prescription, we can deduce that the difference equates to -0.75DC in her right eye and -1.25DC in her left eye. This means that when the lens is fitted on the flattest K, the difference between the K readings will create a negative powered tear lens that will correct the astigmatism completely in both eyes for his nurse, negating the need for toric lenses (Gasson and Morris, 2010, pp. 137 – 139). Multifocal contact lenses are an excellent way to correct presbyopia and exist both in soft and hard lens designs. Simultaneous designs such as concentric ring multifocals (MF) are fairly common such as the Oasys for presbyopia lens, [Dk 147, Water 38%, 8.4mm base curve, 14.3mm diameter, (JJvisioncare, no date)] which provides both distance and near vision in one lens. They do this based on pupil size and often are split up between centre distance (CD) lenses for the dominant eye in most cases and centre near (CN) lenses for the other eye. Depending on the level of illumination, a certain working distance will be favoured over the other as the concentric rings are positioned at intervals which the pupil size will coincide with. This MF design does increase the amount of glare experienced by the patient due to the rings and can also decrease contrast sensitivity due to superimposed retinal image sizes if CD and CN are given (Gasson and Morris, 2010, pp. 277 – 282). I would not recommend a MF soft lens for this patient as it will not correct her astigmatism. Daily MF toric lenses do not currently exist, however monthly soft MF toric lenses do exist with one lens type being the Proclear multifocal, a hydrogel lens with low Dk and high water content [Dk 42, 62% water content, (Coopervision, no date)] something definitely less than ideal for our patient’s desired wear schedule. Bifocal RGP lenses exist providing excellent distance and near vision and use the lenses movement on the cornea. The lens moves up as the eye rotates down, bringing the segment into the pupil’s path and allowing the patient to read. As the eye rotates back up, the lens moves down and the segment moves out of the pupils path and distance vision is restored. (Gasson and Morris, 2010, pp. 277 – 282) RGP bifocals such as the Boston Multivison lens would be an excellent choice for this patient if she were to adapt to them due to correcting astigmatism through the tear lens, allowing her to see distance and reading in one package and allowing plenty of oxygen to pass through the lens. Another successful form of CL correction for presbyopia is monovision (MV), in which one eye is optimally corrected for distance acuity and the other is corrected for near vision (Weissman, 2006, pp. 20 – 20). MV does not compromise lens fitting options and is a highly versatile option and is the least complicated method of dealing with. The distance prescription would be worn in the dominant eye and the reading prescription would be worn in the non-dominant eye, with the brain suppressing images from one eye depending on the working distance. The issue with MV however is that stereopsis is lost as binocular vision is not being utilised. This can be an issue for this nurse if she is required to carry out tasks that require accurate judgement of depth like administering an injection to a patient or driving. If the concept is thoroughly explained initially, there is a much higher chance of acceptance of MV and seeing that she hasn’t worn CLs before, she is very likely to adapt. (Gasson and Morris, 2010, pp. 277 – 282) The other alternative to this would be just to correct her distance prescription with contact lenses and to give her a separate pair of +1.75DS reading spectacles which although a viable solution, can be inconvenient for her and defeats the purpose of replacing glasses with full time CL wear. Some special advice for this patient would include managing her grade 1 blepharitis, which in its current state will not impact lens choice or length of wear if managed correctly. I would advise her to apply hot compresses to her lids and recommend a gel like Blephagel in order to accelerate debris clearance. I would advise her against using baby shampoo which is a surfactant, as it will break lipids in her tear film and will further detriment her dry eyes. I would advise her to administer artificial tears into her eyes which are CL compatible in order to maintain extended comfort all day. I would advise her to thoroughly clean her lenses daily if choosing a non daily lens by rubbing and rinsing in preservative free multipurpose solution, or alternatively recommend peroxide solution and let the lenses fully be cleansed without the need to rub and rinse. My overall recommendation after all things considered would be to fit this patient with the soft bi-monthly Acuvue Oasys toric lens with HydraClear technology to permanently lock a high volume of wetting agent inside the contact lens (JJvisioncare, no date). I would utilise monovision with distance dominance to correct for presbyopia, thoroughly explaining to her the mechanics of monovision and what to expect, as not to be overwhelmed by loss of stereopsis and to increase the overall likelihood of acceptance. I’d also tell her to take precaution if driving. My reasoning for this is heavily based off her wearing schedule in tandem with her dry eyes and her working environment. In order to achieve the wear schedule that she desires, it is extremely important that the lens has a high Dk/T lens in order to prevent hypoxic conditions and a high wettability in order to maintain corneal hydration, minimising discomfort and thus allowing said wear schedule taking into account her dry eyes. She is a nurse so automatically this puts her at a higher risk of infection, hence a lens more frequently replaced would be ideal to prevent deposit build up from affecting her too much and overall decrease the risk of infection. I would recommend her the peroxide solution to further clean the lenses and to decrease the risk of infection and to apply artificial tears for extra comfort. 2199 words Bibliography AIR OPTIX ® AQUA Contact Lens(no date) Available at: http://www.airoptix.com/contact-lenses/aqua.shtml (Accessed: 28 April 2015) CooperVision (no date)Proclear multifocal toric. Available at: http://coopervision.com/practitioner/our-products/proclear-family/proclear-multifocal-toric (Accessed: 25 April 2015) Efron, N. (2012) Contact lens complications. Third edn. Edinburgh: Saunders (W.B.) Co Frequency 55 aspheric | CooperVision UK(no date) Available at: http://coopervision.co.uk/contact-lenses/frequency-55-aspheric (Accessed: 28 April 2015) Gasson, A. and Morris, J. (2010) The contact lens manual: a practical guide to fitting. Edinburgh: Elsevier Health Sciences JJvisioncare (no date)ACUVUE ® OASYS ® for ASTIGMATISM. Available at: https://www.jnjvisioncare.co.uk/contact-lenses/all-acuvue-brand-contact-lenses/toric/acuvue-oasys-for-astigmatism (Accessed: 25 April 2015) JJvisioncare (no date)ACUVUE ® OASYS ® for PRESBYOPIA | Johnson and Johnson Vision Care. Available at: https://www.jnjvisioncare.co.uk/contact-lenses/all-acuvue-brand-contact-lenses/multifocal/acuvue-oasys-for-presbyopia (Accessed: 25 April 2015) MEDICAL, D. E. (no date) Diagnostic tests. Available at: http://www.dryeyesmedical.com/diagnosis/diagnostic-tests.html (Accessed: 25 April 2015) Methods of Stabilisation | Optometry by Catherine Care (no date) Available at: http://optometry.catherinecaregroup.com/method-of-stabilisation/ (Accessed: 29 April 2015) Ruben, M. and editor. (1978) Soft contact lenses: clinical and applied technology. New York: John Wiley SAUFLON (no date)Clariti ® 1day toric. Available at: http://www.sauflon.co.uk/eye-care-professionals/products/clariti-1day-toric (Accessed: 25 April 2015) Sweeney, D. F. (2004) Silicone hydrogels: continuous-wear contact lenses. Oxford: Butterworth-Heinemann Weissman, B. A. (2006) OPTOMETRIC CLINICAL PRACTICE GUIDELINE CARE OF THE CONTACT LENS PATIENT. 2nd edn. St. Louis, MO: American Optometric Association

Only Yesterday Essay

The â€Å"Roaring Twenties† as they’re called, was the period of ten years in the Untied States, which saw the biggest change in society, the boom in the economy, and later the downfall of the nation. This time in America was a time of economic prosperity for the most part; a great social revolution took place and saw the formation of a modern America. All this is the subject, Only Yesterday: An Informal History of the Nineteen-Twenties, written by Fredrick Lewis Allen. Allen writes a very informative book of what happened throughout this great decade, but from the aspect of an ordinary individual. He writes of the social history of the 1920s, with little to mention of major politics and economics. From presidents to fashion, Allen covers it all. It’s an effective look at people in the 1920s, and what life was like. Only Yesterday begins in May 1919, and ends with a brief look at 1930 and 1931. The book begins out with a prologue more or less, in which Allen writes of a fictitious couple, the Smith’s, in the year 1919. Allen, through this prelude, tells the reader of the accomplishments up until 1919, and what is to come in the coming decade. This 14-page introduction lets reader get an idea of what is to come, within the book. It begins with a look at the wartime economy and slow down from it. The period of the so-called â€Å"Red Scare† is written in detail in this book. Allen writes of the terror during this time, from everything like Attorney-General Mitchell Palmer’s raids on radicals, labor strikes and anarchism, and the intolerance of the early 1920s. The Ku Klux Klan also played a major part in this period. The early 1920s was a great time of mass hysteria, and intolerance for anything â€Å"un-American†. In one such story Allen writes about, how a black boy is stoned to death in a lake by whites on the shore, in the summer of 1919. Even though this existed, the 1920s brought great change. The first radio broadcast was in November 2, 1920. Allen talks about the social times changing during this time as well. Everything from sports to makeup was becoming an obsession, like baseball and tennis for the guys, and bathing suits and makeup for the women. During this time new games such as Mah Jong from China and crossword puzzles, and new songs, all which captured the  American spirit, as well as many other things, which thrilled Americans. As Allen writes, â€Å"A few weeks later there was new national thrill as the news of the finding of the tomb of King Tut-Ankh-Amen, cabled all the way from Egypt, overshadowed the news of Radical trials and the K.K.K.† This new time was the social revolution for the people. Ladies began smoking and drinking in public, skirts became shorter, the use of makeup, and the quest for slenderness began. The twenties was also a time of relaxed spirituality. Many looked at society as more important than religion. Celebrities replaced religion in some cases. The younger gernartion searched for things such as passion and thrills, and were much more open with their sexuality. Charles Lindbergh and his trans-Atlantic flight threw him to stardom. Impressing others became the â€Å"thing to do†, and sexual appeal was big. Also during this time of social revolution, prohibition was in full swing, while the 18th amendment was passed, and did reduce drinking in the country, it wasn’t very effective for a number of reasons. The mob and Al Capone ran â€Å"bootlegging† of alcohol. Racketeering was introduced during this time, many people looking for the get rich quick schemes, brought them into illegal activities such as bootlegging and such. People were just discovering themselves during this time and speak-easies and social clubs became the rage. Women would openly drink and smoke to show their independence. Allen talks of the Harding Presidency and the scandals that surrounded it. The return to normalcy as it was called; he returned the presidency to the people. His scandals, which range from sneaking to secret bars in this time of prohibition, to appointing friends and family to the cabinet, and many others. Allen also writes of the Coolidge presidency and the prosperity along with it. The stock market was in a boom, and the economy pumping. The automobile industry fueled the economy and radios brought the people closer to each other. Under the Coolidge prosperity the â€Å"Big Bull Market† was formed. The stock market grew and grew. The economy grew and couldn’t be stopped, the stocks grew dangerously high, but like all good things, it came to an end. The end of an era came about in 1929 on September 3, after that prices crashed and continued to fall until October 24, when the market began to steady again. Yet, the market fell even more, after that and into 1930  the m arket would be at an all time low. Allen attributes this to a list of seven things ranging from overproduction to the psyche of the American public, all which led to the Great Depression. This is the last thing Allen writes, and he asks the question, â€Å"What was to come in the nineteen-thirties?† With the fall of the market, came the fall of individualism, as Allen writes, â€Å"As the stock prices fell so did the lengths of the dresses†Ã‚ ¦Ã¢â‚¬  These are the things, which defined the decade of the 1920s: oily scandals, non-spirituality, the â€Å"good old days†, and the revolution, which, fell just as soon as was started. The 1920s was nothing like America had seen before. It was returned to the people, people weren’t afraid to speak out, or try something new. What was to come in the 1930s? A new decade, which people needed to survive the depression rather than socialize, and it would dismantle everything, which was made in the 1920s. Only Yesterday, was a very good look at the 1920s. It effectively shows what people went through in this crazy time. This book focuses around the social history of the â€Å"ËÅ"20s, from women’s skirts to the economy of 1929. Allen balances this with the politics of the three presidents, which defined this era. The book is very easy to read, and spares the reader with his simple clear and simplistic style of writing. The book was immensely enjoying, and grabs the attention of the reader immediately. He refers back to the New York Times, on numerous occasions, which seems to be one of his primary sources. He uses many details to back up the stories in which he writes about. While he is not very specific in his writing, he incorporates a lot of information in the book. He told everything from the good, to the bad and even to the ugly, which exposed America’s true sense. Only Yesterday: a great book for anyone looking at the social history of the 1920s: where individuali sm ran wild and â€Å"normalcy† had returned.

Identify the strengths and weaknesses of Tokai UK’s international strategy. Essay

The Tokai Company was founded in 1947 in Hamamatsu, Japan and produced all forms of musical instruments,including a large range of pianos. Tokai instruments first appeared in the UK in the early 1980s when they were imported by a company called Bluesuede Music. At that time the two biggest names in electric guitars were those produced by the American companies Fender and Gibson, who both produced high quality electric guitars but at a price that was prohibitive for the average amateur guitarist. Tokai competed against Fender, with products that replicated the Fender quality and also closely esembled their guitars but for half the price. Not surprisingly the Tokai product stood alone in the marketplace and competed with Fender by making quality instruments available to customers who couldn’t afford a genuine Fender or Gibson guitar. Tokai’s biggest seller at the time was the ST50 which resembled the famous Fender Stratocaster. However, Fender issued writs against Tokai which forced them to change the designs so as to not infringe Fender’s copyright. Imports continued on for a further three years and Bluesuede Music did remarkably well with the product, using sales agents out on the road selling guitars to retailers. Unfortunately, in the mid-eighties one of the partners left Bluesuede owing the company and Tokai a lot of money. At that point Bluesuede had to stop the import of Tokai guitars. At the beginning of 2002 Nick Crane, a British entrepreneur, went to Japan to see Mr Shohei Adachi, the managing director of Tokai, and agreed a deal to import the company’s guitars once more into the UK. This started as a small operation and the products began to trickle into the UK. Shortly afterwards Nick Crane approached Bob Murdoch, who had 25 years’ experience in the music wholesale and retail business. Bob Murdoch saw the potential of these instruments on the European market and became a partner in Tokai UK in early 2002. The company began by working from a small garage, but over the subsequent 18 months turnover increased by 200 per cent and they are now selling into Ireland, Italy and Spain. They had a huge market in Germany but, as we will see later, have now pulled out of the market. Tokai UK now operates from premises on an industrial estate at Dinnington, South Yorkshire. Nick Crane left the company to follow other interests in Spain; Bob Murdoch bought out his partner and now has overall control of Tokai UKÂ  and plans to launch Tokai across the pan-European market.

Fecha de prioridad para obtener la green card

Tu fecha de prioridad es el dà ­a en el USCIS recibià ³ tu peticià ³n para una tarjeta de residencia. Es un dato importantà ­simo para saber cuà ¡ndo tendrà ¡s disponible una visa de inmigrante para ti. Si eres esposo/a, hijo soltero menor de 21 aà ±os, padre o madre de un ciudadano americano tu fecha de prioridad aparece en el documento en el que el USCIS confirma que ha recibido la aplicacià ³n. Pero realmente no es importante a estos efectos. Para ti no hay là ­mite anual en el nà ºmero de visas que se pueden conceder. Por lo tanto,  para ti no aplica el resto del artà ­culo. Por el contrario, si eres: cà ³nyuge de un residente permanente legalhijo soltero menor de 21 aà ±os de un residente permanentehermano de un ciudadanohijo soltero mayor de 21 aà ±os de un ciudadanohijo casado de cualquier edad de un ciudadano entonces sà ­ que la fecha de prioridad es muy importante para tu caso. Sigue leyendo. Los cupos anuales para tarjetas de residencia por razà ³n de familia Si està ¡s en uno de los casos anteriores, para cada aà ±o fiscal hay un là ­mite en el nà ºmero de tarjetas de residencia que se pueden aprobar para cada categorà ­a de peticià ³n por razà ³n de familia. Pero como el nà ºmero de solicitudes que se presentan anualmente es superior al nà ºmero de tarjetas de residencia disponibles esto hace que se produzca aà ±o tras aà ±o una acumulacià ³n de casos. Y se resuelven por estricto orden de presentacià ³n de la solicitud para cada categorà ­a. Y aquà ­ es donde entra en juego la fecha de prioridad. Cà ³mo se sabe si tienes que seguir esperando o si ya hay una visa disponible para ti Tienes que saber tres cosas: tu fecha de prioridad. Puedes verla en el NOA2tu paà ­s de nacimiento. Y si es Mà ©xico, China, India o Filipinas ver si te puede aplicar un cambio de paà ­s (alternative chargeability)tu categorà ­a Las categorà ­as son estas: cuando el que pide a un familiar es un ciudadano americano: Categorà ­a F1, cuando el beneficiario es un hijo del ciudadano y reà ºne estos dos requisitos: es mayor de 21 aà ±os y està ¡ soltero o es viudo o divorciado.Categorà ­a F3, cuando el aplicante es un hijo de un estadounidense y està ¡ casado. No importa la edad.Categorà ­a F4, cuando la tarjeta de residencia se solicita para un hermano de un ciudadano. Estos son 10 pasos para este tipo de solicitud, que da una idea clara de quà © se hace en cada momento y de dà ³nde se producen las demoras. Cuando el que pide la tarjeta de residencia para un familiar es un residente permanente legal: Categorà ­a F2A, cuando el beneficiario es el marido o la mujer de un residente o un hijo menor de 21 aà ±os que està ¡ soltero.Categorà ­a F2B, cuando se solicita para un hijo soltero del residente permanente que tiene mà ¡s de 21 aà ±os. En este caso debe estar soltero, viudo o divorciado. En otras palabras, los residentes permanentes no pueden solicitar una tarjeta de residencia para los hijos casados. Una vez que sabes esos tres datos debes hacer los siguiente: Cada mes, a partir del dà ­a 8 aproximadamente, el Departamento de Estado publica en el Boletà ­n de Visas las fechas de corte (cut-off) para cada categorà ­a de visas de inmigrante para el mes siguiente.   Entonces, lo que tienes que hacer es buscar tu categorà ­a (f1, f2a, f2b, f3 o f4) y mirar la columna de Mà ©xico, si has nacido allà ­, o la del resto del mundo, si has nacido en otro paà ­s de Latinoamà ©rica o en Espaà ±a (o en otro paà ­s que no sea China, India o Filipinas). Y verà ¡s una fecha (escrita a la americana, primero el mes, luego el dà ­a y luego el aà ±o). Eso quiere decir que las peticiones en esa categorà ­a con fecha de prioridad anterior a ese dà ­a tienen ya visa de inmigrante disponible. En otras palabras, toda la tramitacià ³n se acerca a su fin, aunque todavà ­a no se ha completado. Si està ¡s fuera de Estados Unidos, quiere decir que el consulado tiene a su disposicià ³n un nà ºmero para la visa de inmigrante. Y si està ¡s ya en el paà ­s, que el CIS tiene un nà ºmero para proceder a tramitar el ajuste de estatus. Pero si tu fecha de prioridad es posterior al dà ­a de corte que aparece en el boletà ­n de visas, eso quiere decir que tendrà ¡s que seguir esperando. Retrocesià ³n Si todos los meses consultas el boletà ­n de visas es posible que un dà ­a te lleves un buen susto al ver que las fechas de corte en vez de ir adelantando, den un salto hacia atrà ¡s . Esto es lo que se conoce como retrocesià ³n, cuando por la razà ³n que sea no hay visas de inmigrante disponibles para una categorà ­a en concreto o incluso para un paà ­s dentro de una categorà ­a. Suele darse cuando el aà ±o fiscal se acerca a su fin. A tener en cuenta La fecha de corte que aparece en el boletà ­n de visas quiere decir cuà ¡nto han estado esperando las personas que han hecho su peticià ³n en determinada categorà ­a. Pero si ahora presentas tà º una peticià ³n, no quiere decir que ese vaya a ser tu tiempo de espera. Puede ser mayor o menor. Pero en todo caso te da una idea de lo lento que funciona el sistema. Y aquà ­ se puede ver cuà ¡nto se demora todo tipo de trà ¡mite migratorio, desde lo que tardan las residencias a presentarse en Corte, solicitud de visas u otro tipo de peticiones. Para evitar repeticiones a la hora de escribir el artà ­culo, se utilizan las palabras ciudadano, hijos, trabajadores, etc en sentido genà ©rico, incluyendo tanto al hombre como a la mujer. Es decir, cuando se habla de un hijo de un ciudadano hay que entender que tambià ©n se contempla el caso de la hija de un ciudadano o los hijos de una ciudadana. Y asà ­ en todos los supuestos. Consejo y dà ³nde encontrar informacià ³n Toma una test para verificar que tienes los conocimientos bà ¡sicos  sobre cà ³mo obtener y conservar la tarjeta de residencia. Es difà ­cil conseguirla. No corras el riesgo de que te la cancelen por ignorancia. Finalmente, es importante saber dà ³nde encontrar informacià ³n sobre el caso, saber dà ³nde reportar fraudes o dà ³nde solicitar ayuda.