Patent Publication Number: US-7596469-B2

Title: Method and apparatus for prioritizing errors in a medical treatment system

Description:
REFERENCES TO PARENT AND CO-PENDING APPLICATIONS 
     This application claims priority from and is a continuation-in-part of U.S. patent application Ser. No. 11/425,868, filed Jun. 22, 2006 now U.S. Pat. No. 7,533,002, which is a continuation of U.S. patent application Ser. No. 10/893,274, filed Jul. 19, 2004, now U.S. Pat. No. 7,076,399 issued on Jul. 11, 2006. 
    
    
     TECHNICAL FIELD 
     The invention relates to medical generators, for example, for electrosurgical applications, and more particularly to controls for such generators. 
     BACKGROUND OF THE ART 
     Medical generators are widely used in medical treatment systems. Their numerous functions include: supplying energy for treatment, communicating with measuring, monitoring, and/or treatment devices, controlling the activity of one or more peripheral treatment devices (such as pumps or suction devices), computing and analyzing input data, and displaying or otherwise communicating treatment information to a user. With such a wide range of uses, medical generators often communicate with multiple devices, each of whose operational parameters may depend on the activity of other devices. 
     The complexity of multiple inputs and interactions, which gives medical generators their versatility and utility, can also cause more opportunities for errors to arise. These errors can often be difficult for a user to diagnose because of the multiple possible causes of a single problem. For example, in a medical treatment system that monitors impedance while energy is delivered to a tissue through a probe, an excessively high impedance measurement could be caused by vaporization of the tissue, a malfunctioning impedance monitor, or a disconnection of the treatment device. 
     It is often necessary to identify the causes of errors and to fix the errors as quickly as possible to ensure safety, due to the delicate nature of some medical treatment procedures. Frequently, however, individuals operating a medical treatment system do not have a technical background or a detailed knowledge of the way the system works. If there is an error in the operation of the medical treatment system, these users may not understand how to solve the error and may not recognize whether an error is signaling a more fundamental problem. Compounding this complexity are differences in component function with different modes of operation, meaning that one error may have different causes at different times. 
     Currently, some medical generators for use in medical treatment systems use a coded display requiring a user to look up an error code in documentation which may raise follow-up questions to help troubleshoot the problem further. This approach can be time consuming and inconvenient during a medical procedure. Some medical generators use an on-screen display that informs the operator of an error and may suggest possible courses of action. However, many errors, such as high impedance, may have a variety of possible causes and suggested courses of action for resolution. In these cases, it can be time consuming to determine which course of action will resolve the error. If multiple errors are detected additional time and effort will be required to determine whether the errors are jointly or independently caused, and which course(s) of action will optimally and efficiently resolve all errors. 
     U.S. Pat. No. 6,788,965, issued Sep. 7, 2004 to Ruchti et al, discloses a system for detecting errors and determining failure modes related to a non-invasive blood glucose monitor. Ruchti et al. disclose an error detection system that employs a hierarchical series of levels to determine whether or not a given glucose measurement is invalid. Each level utilizes different criteria (e.g. rudimentary specifications, patient history, etc.) for determining the validity of the measurement. Ruchti et al. do not describe a medical treatment apparatus with various functions, modes of operation or multiple inputs/outputs and do not describe an error logic system that may solve the difficulties associated with such an apparatus as described above. 
     A solution which addresses one or more of these shortcomings is desired. 
     SUMMARY OF THE DISCLOSURE 
     In one broad aspect, embodiments of the present invention comprise a method of prioritizing errors in a medical treatment system comprising a energy source and at least one associated device, the method comprising: detecting at least two errors in the operation of at least one of the energy source and the at least one associated device; and prioritizing at least one of the at least two errors based on at least one characteristic of each of the at least two errors. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In order that the invention may be readily understood, embodiments of the invention are illustrated by way of examples in the accompanying drawings, in which: 
         FIG. 1  illustrates a block diagram of an exemplary medical treatment system in which the present invention can be used; 
         FIG. 2  illustrates a block diagram of the components of a generator in accordance with one embodiment of the invention; and 
         FIG. 3  illustrates a flow chart of operations for performing hierarchical error logic in accordance with an aspect of the invention. 
     
    
    
     DETAILED DESCRIPTION 
     A first embodiment of the invention provides a method of error detection and analysis to be used in an energy source, for example a generator  102 , that supplies energy to a system  100  used to treat pain in an animal body, particularly a human ( FIG. 1 ). The system  100  comprises a generator  102  for delivering energy through one or more energy delivery devices  104 . Generator  102  may also control the activity of one or more peripheral treatment devices  108 , such as pumps. Generator  102  can have many inputs, including measuring devices  106  (such as temperature and impedance monitors), inputs that relay information on the presence or type of attached devices ( 104  or  108 ) for example by using an integrated circuit. Attached devices  104  and  108  may be unconnected to one another, may communicate among each other or be connected to one another (for example, an energy-delivering probe having an internal channel to carry cooling fluid from a pump), and/or may be physically connected to the measuring device(s)  106  (for example, an energy delivering probe having a thermocouple mounted in the tip). 
       FIG. 2  shows an illustrative embodiment of the components of generator  102 . Generator  102  comprises an input interface  200  for receiving inputs from measuring devices  106  and, as applicable, attached devices  104  and  108 . An output interface  202  supplies output for controlling or communicating with attached devices  104  and  108  and, as applicable, measurement devices  106 . Monitoring circuits  204  monitor input received via input interface  200  (i.e. input measurements) and monitor output for supply via output interface  202  (i.e. output measurements). Information from the monitoring circuits  204  is communicated to an error detecting unit, such as a microprocessor  208 , configurable by data and instructions  210  for error detection and analysis which may be stored in a memory  212 . Configuration parameters  206  stored in memory  212  can also provide input to the microprocessor  208 . Generator  102  further includes a display interface  214  for outputting a display of error information as further described below. Though shown as separate input and output interfaces, persons of skill in the art will appreciate that a combined input/output interface (I/O) may be employed. Though not shown, input interface  200 , output interface  202  or an additional input, output or I/O interface may be coupled to one or more user input devices (keyboard, microphone, pointing device, scanner, etc.), storage devices, or communication networks for inputting, outputting or communicating data and commands for the operation of the generator, whether treatment operations or error detecting and analysis operations. While shown locally coupled to generator  102 , memory  212  may be remotely located and coupled for communication with generator  102  via a suitable interface (not shown). Display interface  214  may couple generator  102  to a display device  110  (e.g. a monitor) or may comprise a communications interface to another system such as a computer system having a display device for receiving output of the display of the errors. 
     In some embodiments, generator  102  may further comprise an event data recorder, which may be associated with, for example, microprocessor  208  and/or memory  212 . The event data recorder may be operable to store data associated with the operation of generator  102  and/or any devices associated with generator  102  such that the data may be retrievable in the event that generator  102  were to fail. Data that may be stored by the event data recorder includes, but is not limited to, any errors detected in the operation of generator  102  and/or any devices associated with generator  102 , input measurements, output measurements, control signals, configuration parameters and/or treatment parameters. In the event of failure of generator  102 , data regarding the operation of generator  102  prior to failure may be retrieved from the event data recorder for analysis, thus facilitating diagnosis of the cause of failure of generator  102 . 
       FIG. 3  is a flowchart of operations  300  for error detection and analysis, according to a method aspect of the invention. In accordance with the preferred embodiment, operations  300  begin at start block  302 , for example, following assembly of system  100  and power up. At step  304 , input and output measurements are continuously monitored and measured values are compared to respective predefined threshold values or ranges of allowed values, on an ongoing basis. If a measurement is within a threshold or range, no error is generated at step  306  (No branch). When a measurement is beyond a threshold or outside a range, an error is generated (step  306 , Yes branch). Errors can also be generated by comparing current system settings, or configuration parameters  206 , to predefined values; for example, if it has been predefined that the system  100  must reach a set temperature and the total time for the treatment has been predefined, then an error will be generated if the preset time for the system  100  to reach the set temperature (ramp time) is greater than the total preset time for the treatment. 
     Multiple input and output measurements may be monitored allowing the generation of multiple errors at step  306  via Yes branch to step  308 . Once an error is generated, operations  300  classify the error in response to specific conditions of the error. For example, if an invalid temperature measurement is detected, operations  300  may classify the temperature measurement as too low or too high. Many levels of increased specificity of classification may occur. For example, for a temperature measurement that is classified as too low: if the temperature measurement is between 5° C. and 15° C., the error classification may indicate a properly functioning device but a temperature too low to operate; if the temperature measurement is below 5° C., the error classification may indicate a malfunctioning temperature sensor. At step  308  errors will be classified to the maximum extent. An embodiment of a method of classification is discussed further herein below. 
     If at step  310  it is determined that only a single error exists, a detailed error message is displayed describing the error at step  312 . Preferably, corrective action that can be taken to resolve the error is suggested. In one alternate embodiment (not shown), the display of errors (step  312 ) is coincident with or precedes an automated modification of the operations of generator  102 , such as the halting of energy delivery or switching to another mode based on the errors generated. 
     At step  310 , if it is determined that multiple errors exist, operations  300  proceed via Yes branch to step  314 . At this point, the set of errors is analyzed in order to determine whether any errors can be combined, being symptomatic of a particular problem. For example, simultaneous errors showing high impedance and an invalid temperature measurement may be indicative of a broken connector or disconnected device. In a preferred embodiment, the first detected errors are combined to form second errors, if applicable. The combination may be determined with reference to a predetermined lookup table or logic tree, discussed further below, which lists all possible first errors and the ways in which at least some of those first errors may be combined to form new (i.e. second) errors. If at least some of these first errors can be combined (step  314 , Yes branch), such first errors are combined to form second errors (step  316 ). Any remaining uncombined first errors remain as independent errors (step  314 , No branch). All second (i.e. combined) errors and remaining first (i.e. independent) errors are preferably prioritized (step  318 ). 
     At step  312 , first and second errors can be displayed one at a time, or can be displayed in a number of other ways including simultaneously, with all errors appearing at once, in groups, or on separate screens that can be toggled or scrolled. For example, the errors may be displayed in stacked and/or staggered windows, wherein a higher priority error may be displayed in the foreground, for example at least partially obscuring at least one lower priority error. In such embodiments, resolving the higher priority error may cause the display of the higher priority error to be cleared, in effect un-obstructing the display of the next highest priority error. 
     In the preferred embodiment, prioritization of first and second errors  318  is responsive to the degree of complexity of resolving each error, or degree to which resolving one error will resolve other concomitant errors. For example, an error that requires an entire treatment device to be changed is prioritized over an error that requires repositioning a device and not changing the device. As a further example, trend analysis may be used to help determine a likely root cause of an error, as described in more detail below. In such a case, the error detected by the trend analysis may be given a high priority due to the fact that a likely root cause has been determined, such that resolving this error may help to resolve one or more other errors. However, prioritization of errors may also be based on a number of other factors including, but not limited to, the severity of the error, the measurable parameter to which the error relates, the magnitude of the measured parameter that led to the error (for example, the amount of voltage overshoot or measured temperature), the order in which the error was detected, or any other characteristic by which errors can be sorted. For example, in some embodiments, errors may be prioritized based on the relative severity of each error rather than the absolute magnitude of the errors. In other words, if two separate errors are detected, each related to a different parameter of energy delivery, the errors may not be prioritized based on the absolute magnitude of the measured parameters, since the parameters differ, but may rather be prioritized based on the relative severity of each error. For example, an error based on a temperature overshoot of 15 degrees may have a lower priority than a voltage overshoot of 10 V, even though the absolute magnitude of the temperature error is higher than the voltage error, since the voltage error may be indicative of a more severe system failure. Prioritization of errors may occur following the classification of errors, for example as Type 1, 2 or 3 errors as described herein below. 
     Grouping and prioritizing errors may aid a user in resolving system problems quickly and with minimal confusion, which can help ensure patient safety by reducing treatment disruption as both error diagnosis and correction times are minimized. For example, as may occur with a prior art device, a user may receive two concurrent errors showing high impedance and invalid temperature measurement with no indication of what is causing the errors. In such a case, the user would have to check all possible sources of each error, to determine the actual cause(s) of the errors, and to determine whether each error was caused by a problem with the equipment or by a potentially dangerous problem with the treatment itself (e.g. high impedance being caused by tissue vaporization). Knowing if the actual cause of both errors is simply that a device has become disconnected, will allow the user to quickly resolve the problem and continue with the treatment, in accordance with a goal of the present invention. 
     In some embodiments of the present invention, the generator itself may facilitate troubleshooting or diagnosis of one or more detected errors. For example, a generator may be operable to perform one or more test procedures to test the integrity, stability or performance, for example, of an internal generator component or an external device associated with the generator. In some such embodiments, a generator may deliver one or more electrical signals, for example test voltages or current signals, to an associated device in order to ascertain whether or not the device has failed and, if so, where the point of failure may have occurred. For example, a generator may employ Time-Domain Reflectrometry (TDR) analysis to determine the point of wire damage in a cable/probe combination, in order to ascertain whether the point of failure lies in the probe or in the cable. In other words, if a user receives a high-impedance error, it may be indicative of a damaged electrical conductor between the generator and the probe. In order to further diagnose the error, the generator may deliver a test signal to the probe via the cable connecting the probe to the generator and may detect a return signal from the probe/cable combination. If a return signal is detected, this may be indicative of a break in the conductive pathway between the generator and the probe, leading to a reflection of the signal back to the generator. The generator may then employ TDR in order to determine how far along the conductive pathway the failure has occurred, in order to ascertain whether the failure is in the cable, probe or, alternatively, in the generator itself. In some embodiments, a system of the present invention may further comprise one or more components to allow one or more associated devices to be connected to the generator, for example in a loop-through connection, in order to enable the generator to test those devices, as described above. 
     In further embodiments, one or more of the associated devices may be operable to transmit one or more signals to the generator to indicate a mode or point of failure of the device. In such embodiments, the generator may not necessarily be able to perform the testing procedures described above but may be operable to receive signals indicative of device failure from the associated devices and analyze those signals in order to more accurately determine the root cause of a detected error. 
     While  FIG. 3  shows a general flowchart of operations for analyzing and clarifying errors, the criteria by which errors are defined can vary in a number of ways. In the preferred embodiment, the sets or ranges of acceptable output or input measurements, or the thresholds above or below which errors are triggered, such as ranges of temperature, can be changed, or may be made dependent on the values of other measured parameters. As well, in the preferred embodiment, a mode of operation or progress through a treatment procedure, can affect the classification of errors. 
     In one embodiment, three different types of errors (e.g. type 1, type 2 and type 3) may be produced depending on the mode of operation or procedural progress. The operation of the generator  102  may be responsive to the type of error produced. Type 1 errors are generated when immediate patient and/or equipment protection is required. For a type 1 error, treatment operations of the system  100  may be automatically modified, discontinuing all generator output to energy delivery devices  104  and/or peripheral treatment devices  108 . Further treatment using the system  100  requires a system reset. Type 1 errors cannot be immediately resolved by the user and have the highest priority. 
     Unlike a type 1 error, type 2 errors are anticipated to be correctable by the user and treatment may progress once they have been resolved. Generator  102  may respond to a type 2 error by modifying the operation of the system  100  either discontinuing all generator output  202  to energy delivery devices  104  and/or peripheral treatment devices  108  or switching the operation of the system  100  to a predetermined mode of operation dependent on the error. The errors remain displayed until the problem(s) that cause them is (are) resolved. 
     Type 3 errors have the lowest priority of the three types of errors; treatment operations of the system  100  need not be automatically halted or suspended by generator  102  and clear after being briefly displayed, or upon being cleared manually by the user. Whether a given error is classified as a type 1, 2, or 3 error depends on the current mode of operation. For example, an invalid impedance measurement in a standby mode may be due to a reasonable action by the user, such as a removal of a probe in order to inject additional treatment fluid through the introducer needle, but the same invalid impedance measurement in an energy delivery mode could indicate vaporization of body tissue or faulty equipment. 
     Another factor that can affect the classification of errors is the configuration parameters  206  within generator  102 . In the preferred embodiment, generator  102  can be configured to expect a certain number or type of device(s) to be connected to it, and can generate errors based on this expectation. For example, if generator  102  is configured to apply radiofrequency energy through one probe, and two probes are connected, an error will be displayed in order to inform the user of excess connections, even if the probe through which energy will be delivered is working correctly. 
     While the embodiment discussed above describes a system  100  capable of analyzing errors as they occur, based on predetermined criteria, it is also possible that such a system  100  could include analysis of trends in measurements in order to detect errors (for example, producing an error if the temperature drops about 10° C. in about 1 second, wherein the error is detected based on a change in temperature over time, rather than only producing an error if the temperature apparently instantaneously drops below a certain level, wherein the error is detected based on a specific temperature value), or that such a system  100  could detect errors based on analysis of trends in errors (for example, repeated high impedance errors in a given mode, occurring with greater frequency than could be attributed to user actions, can indicate a frayed wire). Trends may be analyzed over the course of one or more treatment procedures or over the course of an extended period of time, for example one or more days or weeks or any other period of time. For example, intermittent connectivity during RF delivery, if occurring with a variety of probes, cables and grounding pads, for example over the course of a single procedure or several procedures over a period of time, may be attributable to a faulty conductive pathway (for example a wire or electrical conductor) within the generator itself. Trend analysis can also be used to create type 3 errors, or warnings of imminent errors. For example, if repeated high temperature errors were to be generated, a type 3 error could be produced to warn the user that they are in danger of causing permanent damage to the system  100  (type 1 error imminent). In one embodiment, ranges of acceptable input data for error determination are dependent on trend analysis of errors; for example, if repeated errors are generated based on a certain measurable parameter, the sensitivity of measurement of that parameter could be automatically adjusted (increased or decreased). Trend analysis may be based, for example, on one or more of: frequency, classification and magnitude of the detected errors and/or measurements. 
     Table 1 shows a portion of a logic tree as used in one embodiment for the classification of errors in a lesion-making system  100 . In this example, the lesion-making system  100  comprises a generator  102 , up to two probes  104  each furnished with electrodes (i.e. one active electrode and one return electrode) for the delivery of energy, measuring devices including a thermocouple and an impedance monitor  106 , and may comprise a grounding pad to be used to the receive the delivered energy. In the example of Table 1, the system  100  is configured to deliver energy through only one probe  104 , and is in “READY” mode, prior to the delivery of energy. 
     
       
         
           
               
             
               
                 TABLE 1 
               
               
                   
               
               
                 LESIONING (READY) (Secondary Probe disabled) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                   
                 CHECK 1 Primary Probe Thermocouple temperature valid? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 Goto CHECK 3 
                 Goto CHECK 2 
               
            
           
           
               
               
            
               
                   
                 CHECK 2 Valid Impedance between RF Active and RF Return? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 E01 
                 E02 
               
            
           
           
               
               
            
               
                   
                 CHECK 3 Secondary Probe Thermocouple temperature not 
               
               
                   
                 present? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 Goto CHECK 4 
                 W11 
               
            
           
           
               
               
            
               
                   
                 CHECK 4 Valid Impedance between RF Active and RF Return? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 Goto LESIONING ON - INITIALIZATION 
                 If High: W12 
               
               
                   
                 (Secondary Probe disabled) 
                 If Low: W13 
               
               
                   
               
            
           
         
       
     
     Consider, as an example, a system configured according to Table 1, whereby a thermocouple  106  mounted on probe  104  was not functioning. In this example, CHECK  1  would find the Primary Probe Thermocouple temperature to be invalid and fail, moving to CHECK  2 . If the impedance measurement was valid, CHECK  2  would pass and error E 01  would be displayed informing the user of a temperature error. Table 2 lists a portion of the display messages for system  100  of the present embodiment. If, in a contrasting example, the probe  104  was properly connected, but was not in contact with the tissue, CHECK  1  would find the Primary Probe Thermocouple temperature to be valid and pass to CHECK  3 . CHECK  3  would find no indication of the presence of a second probe  104  and pass to CHECK  4 . CHECK  4  would find an invalid impedance between the two probes  104  and fail, creating an error. The invalid impedance error would further be classified as a high impedance error, causing error W 12  (see Table 2) to be displayed. If, in the system  100  used in the above examples, a probe  104  were disconnected, both invalid temperature and high impedance errors would result. In this example, CHECK  1  would find the Primary Probe Thermocouple temperature to be invalid and proceed to CHECK  2 . CHECK  2  would then find the impedance to be invalid and would fail, displaying error E 02 , as described in Table 2, which informs the user that the probe  104  is not connected. Thus, rather than displaying separate errors for invalid temperature and high impedance, the invention produces a third, unique, combined error. 
     
       
         
           
               
               
               
             
               
                 TABLE 2 
               
               
                   
               
               
                 Type 
                 Code 
                 Displayed Message 
               
               
                   
               
             
            
               
                 TYPE 2 
                 E01 
                 Invalid Temperature Reading 
               
               
                   
                   
                 Check Probe and Cable Connections Possible defective 
               
               
                   
                   
                 probe or cable. Try new probe and cable if problem 
               
               
                   
                   
                 persists 
               
               
                 TYPE 2 
                 E02 
                 Probe Not Connected 
               
               
                   
                   
                 Check probe and cable connections. Probe or cable(s) 
               
               
                   
                   
                 may be defective 
               
               
                 TYPE 2 
                 E03 
                 Temperature Out-of-range 
               
               
                   
                   
                 Outside 15-100° C. expected range. Probe or cable may 
               
               
                   
                   
                 be defective 
               
               
                 TYPE 2 
                 E04 
                 Secondary Probe Connected But Disabled in Advance 
               
               
                   
                   
                 Settings 
               
               
                   
                   
                 Disconnect Secondary Probe or, if desired, enable 
               
               
                   
                   
                 Secondary Probe in ADVANCED SETTINGS 
               
               
                 TYPE 2 
                 E05 
                 High Impedance Detected 
               
               
                   
                   
                 Check Probe and Cable Connections. Probe or Cable 
               
               
                   
                   
                 may be defective 
               
               
                 TYPE 2 
                 E06 
                 Low Impedance Detected 
               
               
                   
                   
                 Check probe and cable connections. Possible short 
               
               
                   
                   
                 circuit in probe or cable 
               
               
                 TYPE 3 
                 W11 
                 Secondary Probe Connected But Disabled in Advance 
               
               
                   
                   
                 Settings 
               
               
                   
                   
                 Disconnect Secondary Probe or, if desired, enable 
               
               
                   
                   
                 Secondary Probe in ADVANCED SETTINGS 
               
               
                 TYPE 3 
                 W12 
                 High Impedance Detected 
               
               
                   
                   
                 Check Probe and Cable Connections. Probe or Cable 
               
               
                   
                   
                 may be defective 
               
               
                 TYPE 3 
                 W13 
                 Low Impedance Detected 
               
               
                   
                   
                 Check probe and cable connections. Possible short 
               
               
                   
                   
                 circuit in probe or cable 
               
               
                   
               
            
           
         
       
     
     Table 3 provides a manner to classify errors for a system  100  configured to deliver energy through only one probe  104 , similar to Table 1, which is in “ON” (energy delivery) mode. As described above, a system  100  may be configured to have different thresholds above or below which errors are detected, depending on operating modes, or could classify errors differently depending on a current operating mode. For example, in a system  100  configured according to Table 3, if a probe  104  is properly connected but is not in contact with the tissue while energy is delivered, CHECK  1  would find the Primary Probe Thermocouple temperature to be valid and pass to CHECK  3 . CHECK  3  would find no valid measurement to indicate the presence of a second probe  104  and pass to CHECK  4 . CHECK  4  would find an invalid impedance and fail, creating an error. The invalid impedance error would further be classified as a high impedance error, causing error E 05 , as shown in Table 2, to be displayed. Unlike error W 12  in the above example, which corresponds to a Type 3 error, and would display on the generator screen for a number of seconds, but would not modify the treatment operations of the system  100 , error E 05  is a Type 2 error and generator  102  will respond to modify its operations to halt treatment operations (i.e. discontinuing the delivery of energy). Thus, the type of error can depend on a mode of operation of the generator. 
     
       
         
           
               
             
               
                 TABLE 3 
               
               
                   
               
               
                 LESIONING ON (Secondary Probe disabled) 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                   
                 CHECK 1 Primary Probe Thermocouple temperature valid? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 Goto CHECK 3 
                 Goto CHECK 2 
               
            
           
           
               
               
            
               
                   
                 CHECK 2 Valid Impedance between RF Active and RF Return? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 E03 
                 E02 
               
            
           
           
               
               
            
               
                   
                 CHECK 3 Secondary Probe Thermocouple temperature not 
               
               
                   
                 present? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 Goto CHECK 4 
                 E04 
               
            
           
           
               
               
            
               
                   
                 CHECK 4 Valid Impedance between RF Active and RF Return? 
               
            
           
           
               
               
               
            
               
                 Result 
                 Pass 
                 Fail 
               
               
                 Action 
                 Goto LESIONING DONE (Secondary Probe 
                 If High: E05 
               
               
                   
                 disabled) 
                 If Low: E06 
               
               
                   
               
            
           
         
       
     
     Tables 1 and 3 show a portion of logical configuration data for detecting and analysing errors based on a physical configuration of the system  100 . For example, if a system  100  were configured to deliver energy through only one probe  104 , as in Table 1, but had 2 probes  104  connected, the system  100  would find the Primary Probe Thermocouple temperature to be valid and pass to CHECK  3 . CHECK  3  would then detect the presence of a valid temperature reading from the thermocouple  106  attached to the second probe  104  and would fail, displaying error W 11 , which instructs the user to either remove the second probe  104 , if it is not intended to be used, or to enable the use of the second probe  104  (Table 2). 
     Variations to the embodiments and examples described above include, but are not limited to: types of inputs or outputs, the language or classification (e.g. a numbering system) used in the display of error messages, the manner of communicating errors (including displaying the messages, or communicating the errors to other devices for displaying and/or other use), the criteria for combining errors, the classification of types or degrees of error, and/or the specific physical configuration of a medical treatment system using such an error logic, may be employed by any user that is skilled in the art, and are intended to be included within the scope of the invention. The scope of the invention is therefore intended to be limited solely by the scope of the appended claims.