To Loupe or Not To Loupe? That is the Question!

Is magnification really, really necessary for successful strabismus surgery? May be not….. Does magnification benefit the surgeon who performs strabismus surgery? Yes!!

Advantages of Magnification

The surgeon sees the anatomy in more detail in the operative field – enabling more focused attention to finer detail – and contributing to:

• Accurate suture placement
• Awareness of small vessels making it easier to control bleeding
• Accurate identification of tissue layers
• Better visualization of sutures and needles
• Accurate needle placement, enabling a shallow “scleral tunnel” – avoiding scleral perforation

Methods to Achieve Magnification with Loupes

• Power 2.5x to 4.5x (2.5 okay for “younger eyes” but eventually 3.5x to 4.0x is the choice for older surgeons)
• Working Distance + 16″
• A light mounted on a head band and placed between the eyepieces of the loupe is an option many surgeons prefer – this light is especially useful for working in a “hole” such as when doing orbit surgery.

Types of Loupes

• A headband mounted light is a very useful adjunct to loupe magnification in that it improves the view when working in a “hole” and in cases where the surgeon’s or the assistant’s head blocks the fixed operating lights.
• Spectacle mounted loupes are the most popular. They should include distance correction and may have a small bifocal add.
• Presbyopic surgeons benefit from a small bifocal to see at near when looking around loupes
• Head band mounted loupes may be used while the surgeon wears spectacles. They may also be used by several different surgeons. Most surgeons who use loupes purchase the spectacle mounted type.

Want to know more or order magnification loupes? Contact AdmetecVision at www.admetec-vision.com, or call us at our toll-free number: 1-888-670-5063. Prefer to email? You can reach us at contact@admetec-vision.com.

Ready to make your purchase? You can order now online!

(Image courtesy of Wikipedia)

Lupenbrillen in der Zahnmedizin – Gute Sache!

“You can only treat, what you can see, and you can only see, what you know”.  Also sprach S. Kim, der Pionier der Dentalmikroskopie aus Pennsylvania. Es beschreibt „zahnärztlichen Intellekt“. Das Wort  „Intellekt” umpasst umgang mit Informationen –  Wahrnehmungen werden gefiltert, verarbeitet, bewertet, geordnet, verglichen und gespeichert.Dieser Prozeß bestimmt nicht unwesentlich Arbeit am Patienten.

Nikolaus Kopernikus, Johannes Kepler und Isaak Newton wären ohne verbesserte Tele-Optik heute wahrscheinlich genau so unbekannt wie etwa Antonie van Leeuwenhoek, Paul Ehrlich oder Robert Koch ohne eine leistungsfähige Mikro-Optik.

Die Entwicklung der Vergrößerungshilfen in der Zahnmedizin umfasst Operationsmikroskops und Lupenbrillen.  So wird an Universitäten die Benutzung von Lupenbrillen bereits im Phantomkurs empfohlen. Hauptargumente dafür sind eine Verbesserung der Prozess- und Ergebnisqualität sowie auch ergonomische Aspekte.

Dentale Vergrößerungshilfen sind Kopfgetragene Mikroskope, digitale 3D-Sehhilfen, Lupensysteme nach Galileo (Vergrößerungsfaktor bis 3,5) oder Kepler (Vergrößerungsfaktor etwa 3,0 – 5,5).

Auch in der visuellen Kariesdiagnostik zeichnet sich der Einsatz von Vergrößerungshilfen durch eine signifikante Erhöhung der Sensitivität aus (man entdeckt mehr Karies). Auch bei der visuellen Verifizierung eines cracked tooth syndrome (Infraktion im Dentin) leistet eine geeignete Vergrößerungshilfe gute Dienste.

Eine korrekte Diagnose setzt Erkennen und Wissen voraus, und eine korrekte Therapie basiert auf einer korrekten Diagnose. Ein vergrößertes Sichtfeld ermöglicht also genaueres Arbeiten. Das hat zur Folge, dass bei invasiven Eingriffen potentiell weniger Schaden entsteht. Aus dieser Überlegung heraus gibt es kaum Argumente, weshalb Patienten den Gebrauch einer geeigneten Vergrößerung bei invasiven Eingriffen vorenthalten sollten.

(Source and image: Courtesy of SPITTA DentalKompakt)

Why Loupes are a wise long-term investment

Since the 1980s, TV series such as Chicago Hope, Grey’s Anatomy, ER, and House M.D. have been featuring surgeons operating while wearing loupes. It makes the show look authentic and the doctors in it as highly regarded professionals. They use of the best equipment available in order to provide excellent care to their patients.

When it is time to buy loupes, an appealing frame looks is part of it. But the major consideration is how the optical equipment will perform and how will it stand up to everyday use.

The two most common types of loupe configurations available are flip-up and through-the-lens (TTL). Through-the-lens optics are customized to meet the clinician’s individual needs. They are permanently glued in place. The main advantages of using TTL loupes (compared to flip-ups) are:

1. The optics stay aligned
2. They are well-balanced
3. They are light-weight
4. They provide a wider field of vision (the optics are close to the eyes)

The TTL setup is similar to top-lined reading glasses where the wearer looks over the optic to view the room using distance vision and though the optic when viewing the patient’s mouth at close range.

Flip-up telescopes are adjustable. Some clinicians with strong prescriptions or bifocals therefore prefer flip-up telescopes because the optics can be flipped up and out of the way. When wearing flip-up telescopes, it is advised to use a head strap that is fastened securely around the wearer’s head. Flip-up loupes are adjustable and can be changed to different frames if wanted. It is easy to change a prescription in a flip-up loupe if the vision of the clinician changes.

Choosing a lower magnification level offers a wider field of vision and a more forgiving depth of field when looking through the optic area than higher magnification. Stronger telescopes zoom in to a narrow field and are difficult to work with independently.

When choosing optics make sure your loupes are:  light-weight, have a wide field of vision, have three-dimensional image qualities,and have very sharp high-resolution image. For these reasons, Admetec-Vision is often the preferred choice.

Good frames are made of titanium to pass the test of time and to ensure daily use. The purchase of a loupe is a long-term investment. It is important to buy a quality product that will stand up to daily use to prevent the need to repurchase in a short period of time.

Editorial note: The full  article was originally published in Hygiene Tribune US, Vol. 2, Issue 1, 2009.

AdmetecVision Salutes David C. Knight M.D. on being named Humanitarian of the Year

David C. Knight, MD, a general surgeon who has practiced at Waterbury Hospital for more than 25 years, has been named the hospital’s “2011 Humanitarian of the Year” for his work bringing medical supplies and expertise to underdeveloped countries across the globe.

Knight, who is the Associate Program Director of Waterbury Hospital’s General Surgery Residency Program, has helped save countless lives over the past several years through a non-profit organization he founded that provides much-needed surgical “loupes” to surgeons in Third World countries. Loupes, which are commonplace in the U.S. and other developed nations, are high-tech optical glasses that allow surgeons to identify and focus on minute details during the course of a procedure.

In 2006, while touring hospitals and medical clinics in Vietnam and Cambodia, Knight developed a friendship with a Cambodian plastic surgeon who told him he routinely conducted procedures without the assistance of loupes. The encounter prompted Knight to form Loupes Around the World, an organization that works to raise donations to provide loupes to surgeons in Third World countries. Since then, the organization has provided 182 loupes to surgeons in more than 42 countries.

Besides his work raising money for loupes, Knight has also taken part in several humanitarian missions to the African nation of Liberia, which is recovering from a recent civil war that decimated much of its medical infrastructure. Before the war, the country had over 400 physicians treating a population of over 3.5 million; after the war, there were only 50 physicians remaining, six of them surgeons. Knight has conducted four missions to the country, providing badly needed assistance and teaching to Liberian physicians working in the country’s largest hospital in the capital of Monrovia.

Knight will be recognized during the hospital’s 12^th Annual Charity Gala on Saturday, November 19 at the Villa Rosa (Ponte Club)

(Credit Ronald DeRosa)

The Use of Loupe Magnification In Microsurgery In The Third World: A Trinidad Experience

By: Maniram Ragbir, Consultant, Surgery, Plastic Surgery, General Hospital, POS, Trinidad

A  retrospective analysis was conducted of 38 patients in whom microvascular techniques were used for reconstruction at the General Hospital, Port-of-Spain.

Microsurgical techniques are applied to many aspects of reconstructive surgery. However, the operating microscope is still a very expensive piece of equipment and may not be readily available in the third world.

Microsurgical success with loupe magnification is well documented. In their publication, the authors analyze the effectiveness of microsurgical procedures performed in Trinidad over a 15 year period with the use of loupe magnification. Aim was to determine the effectiveness of microsurgery in the third world.

Methods and Results:

• A 15 year retrospective analysis of microsurgical procedures performed with the aid of loupe magnification was done at the General Hospital, Port-of-Spain, Trinidad.

•  There were a total of 38 cases, which included 12 replant surgeries; 12 free tissue transfers; 5 supercharged TRAM flaps; 4 facial nerve repairs; 5 peripheral nerve repairs with grafts.

•  The age range was 12 to 65 years with 23 males and 15 females. All procedures were performed by one of two trained microvascular surgeons with the aid of loupe magnification.

Complications included two failed hand replants, partial necrosis of one TRAM which was salvaged with a pedicled latissimus dorsi and minor necrosis of one latissimus dorsi flap.

Conclusion:
With appropriate training microsurgical procedures can be successfully performed with loupe magnification in the third world.

The use of loupe magnification in microsurgery was well justified in trained hands. Its use at this center is advocated on the grounds of cost effectiveness, portability, efficiency, and operator freedom. The purchase price of the instruments is nominal in comparison with the operating microscope.

(Source and image: Internet Scientific Publications http://www.ispub.com)

How to Choose Your Magnification Loupes – Part II

This blog post is an continuation of our previous post.

Test the working distance
The working distance refers to the distance between your eyes, and the patient’s mouth. You can measure this while assuming your normal working position, making sure you are: comfortable, that your back is straight, and that you are not leaning forward too much.

Perhaps you could ask someone to assist you in this procedure. You can also use the following overview to help determine the best working distance for your personal needs:

Height:
<170 cm (5ft 7 in) 170-190 cm (5ft 7 in to 6ft 4 in) >190 cm (6ft 4 in)

Sitting:
340 mm (14 in) 420 mm (16 in) 500 mm (20 in)

Standing:
420 mm (16 in) 500 mm (20 in) 550 mm (22in)

Check the field of view.
The field of view is the area that is visible and in focus, while looking through the loupes. A larger field of view is preferred, as there is a larger area visible through the loupes, and there is less need to move your head around . The size of the “field of view” also corresponds directly to the magnification factor.

A loupe with a lower magnification factor will have a larger field of view, and vice versa. All loupes utilize high performance lens systems that provide an extra wide field of view (up to 125mm / 4.9 inch).

Check the depth of view.
The depth of field is the depth of the area that is visible as well as  in-focus, while looking through the loupes. A larger depth of field is preferred, as there is a deeper area visible through the loupes. The size of the “depth of field” corresponds directly to the “working distance”.

A loupe with a longer working distance, will have a larger depth of field, and vice versa. The size of the “depth of field” also corresponds directly to the magnification factor.

A loupe with a lower magnification factor, will have a larger depth of field, and vice versa. All loupes utilize high performance lens systems that provide an extra large depth of field (up to 120mm / 4.7 inch).

Test the weight of the loupes.
Weight is an important factor when choosing a new loupe, especially if the loupe is to be used for longer periods of time. Lightweight loupes are more comfortable, and in the long term, will reduce tension and other complications. Ultra light weight loupes, offer the maximal comfort. All loupes utilize extremely light weight materials.

Regarding the Keperlilean loupes, these loupes are heavy. When choosing these, opt for the headband style, which will be comfortable for using a long time.

How to Choose Your Magnification Loupes – Part I

The first step is to choose the correct magnification and working distance to ensure that that you will work in ergonomically with your new loupe. Only with the correct working posture can you reduce eye strain, back / shoulder / neck tension, and stress-induced headaches. Furthermore, good ergonomics have shown to improve information processing and decision-making.

Low resolution, color distortion and flatness of the image should be avoided. Resolution is defined as the optical system’s ability to form distinguishable images of objects separated by small distances, or to recognize fine detail.

Looking with loupes at the testing objects and selecting an area of tiny details that can only be seen with magnification, is an excellent way to test loupes.

Chromatic aberration is an often-used term, referring to color distortion. Each color has a different wavelength and the first color that generally comes out of focus is blue. Quality loupes such as AdmetecVision’s do not show any blue haze just to the side of black lines on white paper.

Spherical aberration is another term that is often used. It refers to the flatness of the image. When viewed through quality loupes, an object will not exhibit any spherical aberrations as curved or spherical.

To evaluate loupes for their true optical performance, one must be trained to see the differences on such complex images. For most users, a simple piece of graph paper with black lines will suffice to reveal the difference between mediocre and high quality loupes.

The level of magnification used is mainly based on personal preferences. However, there are a few guidelines that are helpful for choosing the best magnification.  The lowest comfortable magnification level must be selected, since this will provide the widest field of view. There is some commonly used and recommended magnification for loupes:

Ophthalmic Microsurgery with Surgical Loupes

Ophthalmologists are micro surgeons, trained to operate with precise control and meticulous detail on one of the smallest organs in the body. They therefore rely on a variety of magnification instruments to operate. Many external, oculoplastics and pediatric procedures can also be performed with high quality surgical loupes.

Surgeons from a wide range of microsurgical subspecialties use surgical loupes on a routine basis in their practices. Loupes can provide up to six times magnification compared with operating microscopes, which provide up to 40 times magnification. While operating microscopes are usually necessary when performing procedures on structures that are less than 1-2 mm, loupes are less expensive, easier to use, and mobile alternatives for procedures requiring less magnification. Amongst the range of surgical sub specialists, Ophthalmologists depend relatively heavily on operating microscopes and surgical loupes.

Several factors should be taken into consideration when purchasing surgical loupes.

Resolution
Resolution depends on the design and quality of the lenses used in the loupes. It is the primary factor in determining the overall quality of the loupe. Lenses used by Admetec-Vision provide excellent resolution.

Width of the loupe field
Ophthalmic surgeons normally prefer a large field-width, since a wider loupe field allows the surgeons to keep their instruments in perspective with the area of focus. The width of the field is also determined in part by the design and quality of the optics.

Magnifying power
Ophthalmic surgeons usually prefer loupes magnifying between 2.5X to 4X. Some procedures require more magnification than others, and a surgeon performing oculoplastics procedures may require loupes with different magnification compared with those surgeons performing pediatric strabismus procedures or scleral buckles.

Depth of field
An important factor the loupe’s depth of field. The field depth is a measure of the loupe’s capacity to focus across a given distance.

Other factors
Other factors in selecting surgical loupes are the weight of the instrument and the working angle of the loupes. Most surgeons prefer lighter frames to minimize strain.

Working angle
This optical declination angle is the angle to which the surgeons lower their eyes in order to obtain the optimal working position through the loupes. Most surgeons measure their angle by sitting in their optimal working position with their eyes closed, then opening their eyes to ensure that their loupes match their working angle.

Histoire de la microchirurgie: des lunettes-loupe à la télémicrochirurgie

Par : T. Awada, M. Beck, P. Liverneaux (Mulhouse) présentés par J-B. Andreoletti

La microchirurgie est la révolution chirurgicale qui a marqué le XXème siècle. Elle a ainsi rendu possible le fantasme des chimères en permettant les réimplantations de membres et les transplantations d’organes.

Mais comment passe-t’on d’un microscope monocculaire qui permet d’examiner des lames minces à 7 cm de distance seulement avec un grossissement faible et des aberrations chromatiques, à un microscope qui permet des gestes délicats de microchirurgie en respectant les contraintes d’un bloc opératoire?

Qui eut l’idée le premier d’utiliser un microscope pour opérer? Suivons les pères de la microchirurgie, depuis les premières plaies examinées à la loupe et éclairées à la bougie au XVIIème siècle, en passant par les premières lunettes-loupes dotées d’un système d’éclairage ingénieux, inventée par l’opticien Heinrich Westien pour les travaux de dissection de son ami zoologiste Schultze et que l’ophtalmologue Allvar Gullstrand ne manqua pas de s’approprier… jusqu’à l’invention du très ingénieux microscope opératoire dont la paternité est partagée entre Nylen, Holmgren et Maurice Sourdille…

Le plasticien Harry Buncke transplantait des oreilles de lapin dans son garage pendant que le Dr Sun Lee, père de la microchirurgie expérimentale, travaillait à créer un modèle animal petit, reproductible et peu couteux : le rat ! C’est ainsi que ses travaux en microchirurgie permirent de révolutionner la recherche pour les greffes d’organe et en immunologie.

Le mot « microsurgery », généralement attribué à Jules Jacobson, premier chirurgien à avoir réalisé des anastomoses vasculaires sur des vaisseaux de très petit calibre (1-2 mm) dans les années 60’s, est en fait apparu dans une nouvelle de science fiction américaine plus de 20 ans auparavant ! Hier la microchirurgie était de la science-fiction… aujourd’hui la télémicrochirurgie est assistée par robot… Demain déjà, la nanochirurgie transforme notre façon de penser la chirurgie.

Ideale Werkhoogte voor Tandartsen die een Loepbril Gebruiken

Voor het bepalen van de werkhoogte moet de werkstoel de houding van de tandarts goed ondersteunen. De hoofdsteun wordt verschillend ingesteld voor behandeling in de onderkaak of bovenkaak – immers, bij behandeling in de bovenkaak is indirect zicht vanaf de achterzijde van de patiënt. Voor een rechtshandige tandarts is de zitlocatie dan ook tussen 10.30 en 11.30 uur. Het occlusievlak van de bovenkaak wordt 20º/25º naar achteren gekanteld ten opzichte ten opzichte van de verticaal.

Bij de behandeling in de onderkaak vanaf de achterzijde van de patiënt wordt het occlusievlak van de onderkaak in een hoek van ca. 40º geplaatst ten opzichte van de horizontaal.

Plaatsing van armen en handen is van groot belang. De bovenarmen zijn naast de romp en mogen tijdens het werk maximaal 10º naar voren gaan om de belasting op de armen en de schoudergordel tot een minimum te beperken.

Uitgaande van een horizontale lijn is de hoek 90º tussen boven- en onderarmen. De onderarmen worden tijdens het werk minimaal 10º en maximaal 25º omhoog geheven. Voor het bepalen van de werkhoogte zijn de onderarmen ca. 10-15º omhoog t.o.v. de horizontaal.

De plaats waar de handen zich nu bevinden wordt ook wel de boekleesstand genoemd. De kijkafstand is comfortabel en het is mogelijk vanuit een optimale lichaamshouding zicht te verkrijgen op het werkveld.

De afstand van de ogen tot het werkveld is hierbij 35-40 cm voor een tandarts met een gemiddelde lengte. Bij gebruik van een werkbril/loepbril moet de bril dus op deze werkafstand aangemeten zijn. Vaak worden werkbrillen op een te kleine werkafstand aangemeten waardoor de tandarts gedwongen wordt in een ongunstige houding te werken. Dit is eenvoudig zelf na te gaan door op te meten op welke afstand men scherp zicht heeft met de werkbril.

Bij veel brillen ter correctie van bijziendheid wordt een extra positieve correctie toegepast om een vergroting van het werkveld te verkrijgen. Dit heeft ten gevolge een kortere werkafstand wat ongunstig is voor de werkhouding.

(Bron en afbeelding: Medisch Ondernemen)