A:   Telemetry systems are complex and challenging to design to high levels of reliability and in vivo performance.  Before selecting a vendor for your particular application, we recommend checking to see if independent, peer-reviewed publications exist to verify actual product performance. Do your homework.  Product performance and reliability are not abstract concepts but a real fact of life.  Your research success is directly linked to the performance of your measurement equipment.  Before making a system purchase, review respected publications and talk with peers who are using DSI and even with those using competitive products. 

DSI products have been successfully used and cited in over one thousand independent publications. The DSI staff is very happy to help you locate the study results of most interest to you, and to provide references for scientists performing similar research.

DSI Perspective
The body of research data generated over the past 25 years using DSI products is impressive:

• All of the top tier drug development and Contract Research Organizations (CRO) use DSI products.
• DSI products are in 1,800 locations and more than 40 countries around the world.
• Telemetry data have been received from over 300,000 laboratory animals.
• Implantation and telemetric data have been collected from species that were not even dreamed of 25 years ago.
• Citations and research data have been published in more than 1,200 peer-reviewed articles and more than 400 scientific journals*

A:  A transmitter refurbishment or exchange policy enables a review and rectification of normal wear and tear a device endures over prolonged in-vivo exposure.  No matter what type or brand of transmitter, there are numerous potential challenges over time given the harsh in vivo environment.  Most transmitters allow moisture ingress and this moisture will cause failure over time.  Recharging technology is readily available and has been used in select, human implantable applications, typically when high energy outputs are required. Recharging is not without challenges and the cost of having to redo a study due to transmitter failure or confounded data is likely to vastly outweigh the cost of refurbishment.

DSI Perspective
Over the past several years, DSI has carefully evaluated the potential value that recharging might offer for wireless animal monitoring applications. DSI has concluded that the recharging technology currently available is not suitable for the vast majority of mainstream monitoring applications, as the drawbacks outweigh the benefits.  Implant battery warming during charging, larger implant size, excessively long recharge times, and implant vs. charger orientation requirements are problems that have been difficult and in many cases impossible to overcome, resulting in the withdrawal of several transmitter models from the research market.  DSI is committed to using only tested and proven approaches that meet our customer’s needs for performance and reliability.
Here’s why battery applications are effective:

Application Proven: Given DSI’s proprietary, low power-drain telemetry technology, and circuit design, transmitters with tested and proven standard batteries will last for the intended life of the research subject and meet the needs of most monitoring applications without any need for recharging. This technology enables researchers to avoid the risk and inconvenience that can arise with recharging.

Transmitter Reliability: It is important that researchers do not equate rechargeable batteries with the ability to last in vivo indefinitely. Implants without advanced design may function for only a matter of months. With DSI’s 25 years of experience, we have proprietary methods of extending the in vivo implantable devices lifetime and continually invest internally to maintain quality and increase the standard industry wide.

Refurbishment: If researchers wish to explant and reuse transmitters, regardless of whether or not they are rechargeable, the transmitter will eventually need to be refurbished to assure reliability. When refurbished by DSI, transmitter catheters, leads, batteries, device housings, and circuitry are thoroughly examined, replaced, and tested. The result is a “good as new” transmitter with the same warranty coverage as a new transmitter.
Convenience / data integrity: For optimal recharging, current technology requires charging apparatus be precisely and consistently placed within centimeters of the implanted battery. If recharging is not performed with high reliability, the likelihood of lost data and confounded study results increase study risk.

DSI pioneered the concept of transmitter refurbishment in order to lower production costs and to pass those savings on to researchers. This has been a very popular service, and provides customers with the highest transmitter quality and reliability, so as not to adversely impact the enormous time and expense invested in research.

A: Some commonly used radio frequencies for consumer goods like 2.4 GHz  are more susceptible to signal drop out due to body tissue attenuation when used for implanted devices. In vivo wireless transmissions are also susceptible to electromagnetic interference.  Systems need noise filtering or other means of minimizing effects of electromagnetic interference to assure that physiologic signals are not lost or destroyed.  

The telemetry technology used for chronic implantation needs to be power efficient in order to provide the best mix of device size, features, range and longevity.   If the power consumption for a given application is too high, overall device performance or longevity will suffer and the manufacturer will need to consider rechargeable batteries, which can compromise customer ease-of-use and / or compromise desired  “free roaming” study outcomes and animal health due to device size, animal restraint, potential heating during recharging and prolonged exposure to Electro Magnetic Fields (EMF) . 

DSI Perspective

Compare specifications, and consult with experienced and trusted peers.  

As always, DSI recommends choosing products that are well tested for your application to identify any drawbacks.  Always seek proof of successful product performance from independent researchers in order to assess the potential risks and whether or not such risks may jeopardize your study objectives.   DSI has chosen to use lower frequency bands (Kilohertz or Megahertz) in order to assure more reliable signal reception and minimal signal dropout. This is consistent with with similar frequencies proven in human device applications. (e.g. pacemakers)

A:   It is important for customers to assess the suitability of sensor performance for the target application.  This is most often done by reviewing study outcomes from independent, peer reviewed publications.  A second avenue to assure information accuracy is to contact the manufacturer directly. 

DSI Perspective

For the chronic measurement of pressure signals via telemetry, we will discuss two important aspects:  frequency response and chronic sensor stability.  First, when measuring systemic blood pressure, studies indicate that a frequency response of 30-40 Hz  is adequate for rats and larger animal models, with > 60Hz generally reported for mouse applications. Most other pressure sensing applications require similar frequency response. Literature also suggests that some applications, such as those that involve deriving max dP/dt from left ventricular pressure, require frequency response of > 100Hz for rats and > 70Hz for large animal models. (Main, B)  DSI offers pressure sensing systems with performance specifications which meet or exceed these requirements. It should also be noted that excess frequency response is not necessarily advantageous and could affect resulting calculations.

Secondly, sensor stability is extremely important in chronic monitoring situations as some sensors– such as transducer tipped catheters commonly used in acute applications- can exhibit varying drift rates over time and remain unproven in chronic study.   (Kurtz, TW).  Historically, DSI pressure sensors exhibit very low drift rates, while our most recent product, HD-S21, has an average drift rate of  0.25mmHg/month ( Figure 1 )

Extensive testing of our catheter materials demonstrates long-term biocompatibility of the polymer catheter material while implanted in rats and other species.  For a detailed overview of our transmitter specifications, go to: http://datasci.com/products/implantable-telemetry/Transmitter-Specifications.asp

Peer-reviewed journals cite many uses of our telemetry technology and in specific reference the proven performance characteristics of DSI pressure-sensing catheters for measuring chronic blood pressure in small animals.

Supporting References:
1Kurtz TW, Griffin KA, Bidani AK, Davisson RL, Hall, JE. Recommendations for Blood Pressure Measurement in Humans and Experimental Animals.Part 2: Blood Pressure Measurement in Experimental Animals. Hypertension. 2005; 45:299-310.

2Brooks D, Horner RL, Kozar LF, Waddell TK, Render CL, Phillipson EA. Validation of a telemetry system for long-term measurement of blood pressure.J. Appl. Physiol. 1996; 81(2):1012-1018.

3El-Mas MM, Abdel-Rahman AA. Longitudinal studies on the effect of hypertension on circadian hemodynamic and autonomic rhythms in telemeteredrats. Life Sciences. 2005;76:901-915.

4Van Vliet BN, Chafe LL, Antic V, Schnyder-Candrian S, Montani JP. Direct and indirect methods used to study arterial blood pressure. Journal ofPharmacological and Toxicological Methods.2000 (44) 361-373.

5Main, Bradley. “Cardiovascular Safety Evaluation: Left Ventricular Pressure Measurement in Dogs, Monkeys and Rats.” Eli Lilly and Co. Indianapolis,IN USA. Presented during Advanced Topics in Cardiovascular Assessment during 6th Annual Meeting of the Safety Pharmacology Society. Slide 16.25 September 2006

6H. Nyquist, "Certain topics in telegraph transmission theory," Trans. AIEE, vol. 47, pp. 617-644, Apr. 1928

7Geddes, L.A. “Handbook of Blood Pressure Measurement.” Clifton: The Humana Press, 1991.

A: While methods such as tail cuff are acceptable for screening methods or measurement of gross change at points in time, the American Heart Association (AHA) recommends the use of implanted telemetry for animal studies for most BP applications, such as quantifying hypertension magnitude, BP relationships to other variables (target organ damage), and BP-independent and BP-dependent effects of different interventions or variables (such as drugs, diet, genotype). Telemetry is also recommended for studies identifying intermittent or subtle forms of hypertension or changes in BP, measuring BP continuously over time, measuring BP variability, and determining BP in unrestrained animals.

DSI Perspective

DSI telemetry invalidated some prior data collected using less humane methods:

• Rat tail cuff BP and HR data collected from telemetry-implanted rats showed elevated measurements when the tail cuff was used. This study demonstrated that rats and mice experienced something similar to “white coat hypertension”—an artificially high BP reading that humans sometimes also experience when nervous during a visit to the doctor.

There are many papers published that demonstrate implantable telemetry as the preferred method for physiologic monitoring as well as industry standards. Several of the more influential publications are cited below:

International Conference on Harmonisation –S7A Safety Pharmacology Studies for Human Pharmaceuticals Guidance

In reference to telemetry, the ICH S7A guidance documents states:

In conducting in vivo studies, it is preferable to use unanesthetized animals. Data from unrestrained animals that may be chronically instrumented for telemetry, other suitable instrumentation methods for conscious animals, or animals conditioned to the laboratory environment are preferable to data from restrained or unconditioned animals. In the use of unanesthetized animals, the avoidance of discomfort or pain is a foremost consideration.

A: Purchasing a physiologic monitoring platform is many times a critical part of constructing a lab.  A solution provider that acts as a knowledgeable resource both before and after  such an important purchase enables researchers to make well informed decisions and benefit from those decisions. 

DSI Perspective

The choice of the wrong system can set back one’s research by months and sometimes years if the supplier solution or quality is not well suited to the task.  It is often very helpful to choose a supplier that is making continued improvements in their platform so the customer with continuing research projects can benefit from the future improvements. 

Consider the following points when reviewing physiologic monitoring providers:

1. The company representative should have experience with or understand your application.
   
   DSI has a technical sales force with experience in many hands on physiologic monitoring applications as clients, students or DSI related assistance in client field setup and testing .  All of our technical sales and support desk personnel have a bachelor’s level  engineering or science education with some extending their expertise to Master’s or Ph.D. level degrees.   
   
   
2. The company representative should be able to provide various examples of similar systems based on your application and needs.
   
   DSI has over 25 years experience providing and supporting physiologic monitoring of varied species and applications in research and drug development environments.  Our technical sales force and support staff have access to a wealth of reference data, surgical practices and authored papers that address most applications.  Novel applications are encouraged as these challenge the boundaries of our products and drive the innovation to address new customer needs.
   
   
3. The company should be able to provide onsite and/or virtual product demonstrations.
   
   DSI’s employs a territory based direct sales force that is relationship driven.  Residing in the territory of service provides an opportunity to see and understand the customer’s needs.  In the event a timely onsite visit is not possible, our technical sales force and support staff are equipped to engage in virtual conversations that include simple needs discussions and product overviews  with the potential to also engage in detailed demonstrations, training and trouble shooting.  In regions where DSI does not have a direct sales force, DSI takes great pride in choosing distributors with the experience, aptitude and desire to learn our products and satisfy customer’s physiologic monitoring needs at a DSI approved level anywhere across the globe.

A:  Surgical implantation of some devices may be intimidating for researchers attempting such procedures for the first time. Proper education will increase your success rate and minimize delays.

DSI Perspective

DSI is not simply a product provider.  DSI is dedicated to understanding customer needs from beginning to end and we know that possession of our product does not assure success.  When it comes to implantable telemetry, surgical expertise is a must and DSI takes customer success very seriously.  DSI employs a talented surgical group with a DVM, PhD as our Chief Scientific Officer.  DSI products, new and existing are routinely implanted by our surgical group in a wide range of scenarios extending from product development to client education.  

When discussing surgical education with your prospective provider, make sure to discuss surgical training options and staff qualifications.

DSI understands that not all customers have equivalent surgical knowledge.  To increase success, DSI offers surgical support in many different formats with most being either free or at a nominal charge. 

DSI’s Surgical Support Offering:

• DVD’s reviewing product and surgery basics are available for most telemetry products.
• Annual and partnered surgical workshops are available throughout that year. Details on these events are located on the DSI website.
• Small animal surgery training is available at our world headquarters in St. Paul, Minnesota.  This training is typically tailored to investigator need and can include software and associated training.

Contact DSI to discuss your surgical needs.

A: Most companies will publish their delivery times. Others provide it upon request. In either case, talk to actual customers and ask them how consistently the provider is able to meet their specified lead times.

DSI Perspective

Our primary goal is customer satisfaction through quick and personalized service. DSI is continually working to ensure that your experience with DSI will result in your advocacy of our products and services. Our lead times are product-dependant and typically range in the two to three-week timeframe for telemetry products with lead times on our acquisition and analysis equipment possibly extending longer due to personalized configurations.

At DSI, we realize study needs change and product requirements many times change in an unexpected manner. To accommodate these needs, DSI also offers an expedite program. Details on this program can be found at: http://datasci.com/support/customerservice.asp

• Transmitter delivery times should be predictable and reliable

DSI has more than 25 years of manufacturing experience and has used this experience to provide quality product in a reasonable timeframe.  Our products are manufactured in the United States and shipped globally year round. At DSI we realize study needs change and product requirements many times change in an unexpected manner. To accommodate these needs, DSI also offers an expedite program. Details on this program can be found at: http://datasci.com/support/customerservice.asp

• International shipments

To facilitate shipments to Europe, DSI put in place a distribution point that houses product and handles customer service requests directly for DSI. DSI also has a direct office located near Shanghai, China. Areas outside Europe and parts of China are serviced by distributors with whom DSI has had long standing relationships.

DSI QUALITY POLICY

A: Companies actively engaged in designing and offering high quality products for life science research should be compliant with ISO 9001 standards (International Standard Organization.)  DSI is compliant with such standards and is routinely audited by our large pharmaceutical customers.  Rigorous quality standards serve two purposes. First, they assure a company is selling product that meets customer requirements and establishes specifications. Second, they support customer confidence by ensuring that purchased products have a robust testing process with verifiable records and proven functionality.

DSI Perspective
DSI recommends asking suppliers about their quality standards as many smaller and newly established companies in the life science products arena are not compliant with such standards. 
DSI is committed to providing products that consistently meet customers’ high expectations for reliability, delivery, service, and value.  We accomplish this by understanding our customers’ requirements, by providing innovative products, by performing extensive pre-market beta testing of all new products, and by continuously improving products. No matter how good the quality system, it cannot promise products that meet or exceed specifications 100% of the time as this is unrealistic. In the unfortunate event that a product fails prematurely, a client should have an easy avenue to report the failure and receive satisfactory support.  When considering your telemetry manufacturer, check to see if the company has the ability to promptly respond to any needs for service or product training, on a local or global basis as appropriate.

A. When offering a warranty, the manufacturer makes an important promise to stand behind their products and federal law requires that warranties be available to prospective customers prior to purchasing. Warranty coverage may vary and one should take care to understand the warranty as it many times clarifies what to do when something goes wrong with the product.

DSI Perspective

DSI’s goal is to achieve high standards of product reliability and performance and our Limited Warranty Policy is unparalleled in the wireless monitoring industry – this reflects DSI’s confidence and over 25 years of experience as well as our increasing investments in product design and testing.

The in vivo environment presents significant product reliability challenges, especially for electronic devices used for chronic applications.  Included in our warranty policy is a three-part program covering our implanted transmitters with separate warranty durations for (i) battery life, (ii) implant life, and (iii) maximum warranty period.  DSI has a broad range of transmitters for application from mouse to large animal models, and warranty periods vary based on the transmitter model and its intended application. DSI also offers warranties on our non-implanted hardware products, typically of one year duration. 
http://datasci.com/resources/warranty.asp

A. Research today is a dynamic atmosphere. When it comes to physiologic monitoring , change could simply dictate a new species or demand a more complex approach such as combining acquisition methods across multiuple species.  The chosen physiologic platform must be adaptable to the evolving needs a researcher might encounter.

DSI Perspective

DSI offers a broad portfolio of solutions with a high level of integration for researchers seeking time synchronous data acquisition and analysis using a wide array of sensors.

• Customers use varied species; the telemetry system should be easily compatible with multiple species

PhysioTel transmitters are designed for monitoring and collecting data from conscious, freely moving laboratory animals—providing stress-free data collection while eliminating percutaneous infections. PhysioTel transmitters are offered in various sizes to support a variety of research models ranging from mice and rats to dogs and primates. The shape of DSI transmitters are also designed to accommodate both subcutaneous and intraperitoneal placement. Parameters measured by researchers and scientists include arterial pressure, venous pressure, left ventricular pressure, intra-ocular pressure, bladder pressure, kidney pressure, ECG, EMG, EEG, EOG, respiration, temperature, activity, as well as other parameters. DSI offers a variety of transmitters to improve data quality and simplify studies. All PhysioTel transmitters may be switched on/off in-vivo with a magnet to extend study duration. And when a study is complete, researchers simply exchange their existing transmitter at a fraction of what they would normally pay for a new one. It’s the easy way to reduce cost per study and make your research dollars go further.

• Integrated research also requires the monitoring solution be compatible with many different types of sensors (telemetry, hardwired)
  

The DSI Synchronization option (simultaneous acquisition) allows the user to acquire signals from both telemetry and hardwired sources aligned in time.  Lock step innovation puts DSI ahead of the competition in relation to handling signals of varied origin.  This DSI Synchronization solution provides the best digital synchronization available between implantable telemetry and Ponemah acquisition devices (hardwired signals).

Studies requiring respiratory parameters such as resistance calculations can use a hardwired head-out chamber to measure flow and an implanted pressure transmitter to measure pleural pressure.  Without the tight level of synchronization offered by the DSI solution, the users would not be able to perform accurate cross channel calculations.

The tight signal integration between implantable telemetry and hardwired sources also allows users to combine different study types (i.e. cardiovascular, respiratory, CNS) into a single study, where appropriate, enabling the user to save time and money.

A: The company should have dedicated sales professionals to answer initial questions

DSI Perspective

DSI has a technical sales force with experience in many physiologic monitoring applications as clients, students or assistance in field testing in support of existing clients.  All of our technical sales and support desk personnel have a bachelor’s level  engineering or science education with some extending their expertise to master’s or PhD level degrees.   

• The company should have dedicated customer service staff to process the order

DSI’s  primary goal is customer satisfaction through quick and personalized service. DSI continually strives to ensure that your experience with DSI will result in your advocacy of our products and services.  To accommodate your ordering needs, we have customer support staff located in three centers as well as a direct office located in China.  No other physiologic monitoring provider can match DSI’s ability to support customer needs every step of the way.

• The company should have dedicated support staff to help get the system set-up and answer follow up questions

DSI is available to help you with your questions and concerns. In addition to contact information listed below, DSI provides an online product information request form, online technical support, and online customer service. Please visit these pages to learn more about our services.

DSI Technical Support
Email support@datasci.com
Toll-free in U.S. and Canada
1-800-262-9687 | 1-800-262-9687  
Outside of the U.S. +1-651-481-7400  +1-651-481-7400 
Monday through Friday: 8 AM to 5 PM CST
(except Holidays)

A: The ability to validate your physiologic monitoring system for GLP study use is important, does the company offer the following:

• Validation support services
• Validation Service Package
• Multi parameter signal generator for system validation and training
• Pressure chamber for pressure validation
• Test  Scripts
• Equipment calibration services
• Audit support
• Upgrade Assistance

DSI Perspective

Whether you are validating a system for the first time or revalidating due to a version upgrade, DSI’s  Validation Support Package can assist every GLP user's needs in order to comply with FDA requirements for computer system validation. DSI recognizes that computer system validation is a time-consuming task, and therefore, is provides a Validation Support Package to assist its customers with validating the DSI software and hardware interfaces in order to ease the validation process.

The Validation Support Package is designed to assist with the Installation Qualification (IQ), Operational Qualification (OQ) and Performance Qualification (PQ) phases of the user's validation endeavors. Test documentation and design specifications are provided, as well as other supporting features to assist with reducing the amount of time spent on validation activities and helping the user to culminate a well-rounded validation plan.

Vendor Audits

FDA regulations state that the User should qualify the vendor to ensure the quality of the productThe DSI software design and development team welcomes its users to perform a vendor assessment. Please contact DSI Customer Service to request additional information regarding On-Site Audits or to coordinate completion of Vendor Audit Questionnaires.