Significance of Endoscope Workstation Development

Endoscopic examination is a diagnostic method based on endoscopic images. It is a very effective examination method used in clinical medicine to examine diseases such as gastric diseases, intestinal diseases, ulcers, and tuberculosis. In the past, during endoscopic examinations, doctors held endoscopes and visually described lesions, which was highly subjective and prone to missed or misdiagnosis. Later, endoscopic display devices appeared, magnifying images onto monitor screens, and the display device's video recorder could also record the examination process. However, its shortcomings were: it could not fix the image to check key lesion sites; it could not store images individually, only the entire process; the videotape and patient medical records were separate, making management inconvenient; the image became blurry after long-term storage of the videotape, losing its diagnostic value, etc. With the significant improvement in computer performance and the widespread application of multimedia databases, the above shortcomings have been successfully addressed. Its advantages include: images acquired by the CCD camera are displayed on the computer screen through a video acquisition card, and real-time freezing, unfreezing, roaming, and zooming functions for lesion images can be achieved; images are stored in digital form and will not be distorted after long-term storage; unified storage of patient medical records and patient images is achieved, facilitating queries, etc. With the development of hospital information systems and the widespread application of the international Internet, the currently widely used multimedia endoscopy databases are increasingly showing the following limitations, which have been addressed by the development of this workstation.

1. Inconvenient operation. Because doctors need to use both hands to coordinate when observing lesions with an endoscope, if they are required to free up one hand to operate the computer keyboard or mouse to collect images, it often leads to inconvenience in using the endoscope or missing the best moment for image acquisition; the endoscope case workstation uses a foot switch, allowing doctors to save images at any time without using their hands.

2. Unfriendly human-computer interface. This is particularly evident in the fact that doctors had to manually input a large amount of Chinese characters to complete a medical record report in the past. This is undoubtedly a barrier for doctors unfamiliar with computer operation, affecting work efficiency. This system uses an intelligent medical vocabulary, allowing doctors to complete a medical record by simply double-clicking selected words with the mouse.

3. Low security. Patient information security is the key to hospital informatization construction. Currently, most endoscopy management systems have low security, in that anyone can arbitrarily open, modify, and delete patient data in the database. Some case management systems require password input to operate, but because there are no corresponding logs, it is impossible to determine who performed which operation on the database information, leaving hidden dangers for hospital informatization construction. This endoscope case workstation uses WIN-DOWS NT WORKSTATION 4.0 as the system platform and NTFS file system, which is unique to WINDOWS NT, for the hard drive, greatly improving security.

1. System composition

The endoscope workstation uses WINDOWS NT 4.0 as the platform and VB6 as the development tool. The workstation uses a foot switch and operates the endoscope through a serial port for easy doctor operation.

1.1 Endoscope workstation foot switch

When doctors use an endoscope to observe lesion sites, both hands need to work together. Currently used medical multimedia systems require doctors to free up one hand to operate the computer keyboard or mouse to collect images, thus often causing inconvenience in using the endoscope or missing the optimal moment for image acquisition. The role of the endoscope workstation controller is to not occupy the doctors' hands, and the image can be saved by using the foot switch, the principle is as follows.

The foot switch of the controller is implemented through serial communication between the single-chip microcomputer and the computer RS232 serial port. Serial communication is one of the main methods of data communication. Because it has fewer connections, low cost, and modulation and demodulation functions, it is suitable for short-distance communication. It should be noted that the serial port of the single-chip microcomputer is TTL level, so an additional conversion circuit is needed to communicate with the PC.

In the software, there are three methods to implement serial communication using VB6, namely:

① Using DOS environment file output relocation.

② Using communication control (MSCOMM) to complete serial communication.
③ Calling API functions to implement serial communication.

The first method, using DOS environment file output relocation, can only achieve simple serial communication with applications, and its use is very limited, such as it does not support parity checking and cannot control serial port status, etc. Using the communication control MSCOMM provided by VB, this control can set the data sending and receiving of serial communication, set the serial port status, and the information format and protocol of serial communication. The main advantages of using VB controls to complete serial communication are: the communication control leaves many complex operations to WINDOWS to handle, and the key for users is to correctly set some of its attributes.
Its main disadvantages are:
① Each communication control corresponds to one serial port. If multiple communication ports need to be accessed, multiple communication controls must be designed.

② Using controls will inevitably increase the application and occupy system resources, thereby reducing the response speed of the entire application.

③ The method of using the controls provided by VB to achieve communication is easy to complete the operation of the serial port as long as the mechanism of VB controls is understood, but the portability is poor.

The advantages of using WINDOWS API to complete serial communication are:
① It hardly increases the system resources occupied by the application, and the execution speed is much faster than using the control method.

② Strong portability. Because the program uses WINDOWS internal functions instead of a third-party control, the portability of the application is significantly stronger than using the control method. Its disadvantage is: programming is more complex.

From the above comparison, it can be seen that using controls to complete serial communication programming is easier, but it sacrifices the system's response speed and increases the memory occupied by the application itself. Although using WINDOWS API functions to implement serial communication is more complex in programming, its execution speed has obvious advantages, and it uses WINDOWS internal functions in API calls, so it will not increase the system resources occupied by the application, and its portability is stronger than using the control method. Considering that the application has already used a large number of controls to complete image acquisition, saving, and display, adding more controls will further reduce the response speed of the program. Therefore, the method of using WINDOWS API is used to complete serial communication.

1.2 Security strategy of the endoscope workstation management system

Medical records have legal effect, and the information recorded in medical records is the patient's personal privacy and is not allowed to be browsed, modified, or deleted at will. Therefore, a two-level security strategy based on the NTFS file storage format of WINDOWS MT 4.0 is adopted on the endoscopy workstation. NITS is a file management system dedicated to WINDOWS NT, which can control which users and groups access which files and folders, and control their access types. For example, some users can be set to have read access to the database, and some users can have the right to modify or delete it.

NTFS includes five standard permission levels:

① Full control: Users can modify, move, delete, and change permissions.

② Deny access: Even if the user has access rights to the higher-level folder, access is not accepted.

③ Read: Users can view the file.

④ Change: You can view and modify files, including deleting and adding new files.

⑤ Special access: User access is defined by a custom standard set.

(a) Operation level

User accounts are assigned through NT WORKSTATION to prevent unauthorized personnel from accessing system resources and patient data. Database folder and database file permissions are set through the NTFS file system. Only operators with the corresponding password are allowed to add, delete, and modify files. The operation process is: Log in to the system as an administrator, select the corresponding database file such as patient.mlb, right-click the mouse, select "Security" in the context menu, add users, and grant corresponding permissions.

(b) Audit level

In addition to granting different users different permissions, the NTFS file system can also perform logging operations. The endoscopy workstation administrator can track the operator's operations by setting the file and object rules in the WINDOWS NT audit rules. The log files in the Event Viewer can reflect which operator performed what operation at what time, such as read, write, or delete operations. Therefore, the security of patient data is ensured at a higher level. It should be pointed out that because event auditing is performed in the background, it will affect system performance, but with the rapid development of computer hardware, the impact can gradually be ignored.

1.3 Quick information entry methods

The graphical user interface is the main means of human-computer interaction in modern software. In order to unify the interface and facilitate the use of operators, the endoscopy workstation uses a full-screen composition method for the graphical interface. This is achieved by setting the border of the form to no border and setting the form display mode to maximized. Considering the actual situation of software operators, the buttons in the software have their specific names, and a dynamic prompt function is also provided, that is, a text prompt automatically appears when the mouse moves to a button. This function is implemented through the TIPS attribute in the control.

In addition to using the graphical user interface, help files, and dynamic prompt functions, the endoscopy workstation uses an intelligent vocabulary input method when completing a medical record report to reduce the pressure on doctors to write medical records and allow doctors to concentrate on the patient's treatment process. The basic workflow is as follows: Doctors can enter commonly used medical terms into the vocabulary, and they can select the corresponding words from the vocabulary when completing a medical record. Words in the vocabulary can be added, deleted, and modified at will. In order to meet the needs of various clinical examinations and enable doctors to quickly select the corresponding words, various vocabularies such as gastroscopy findings vocabulary, gastroscopy diagnosis vocabulary, colonoscopy findings vocabulary, and colonoscopy diagnosis vocabulary have been designed. Doctors double-click the selected words from the vocabulary to complete a medical record report. When doctors right-click the mouse at the endoscopy findings, the program automatically determines the pop-up vocabulary dialog box based on the type of endoscope selected in the medical record. The intelligent vocabulary can be created using the VB application wizard.

Using VB to develop the human-computer interface has powerful WYSIWYG functions, but VB is an interpreted language, which interprets statements and then converts them into calls to WINDOWS dynamic link libraries during execution, so the response speed of applications written in VB cannot reach the performance of compiled languages such as C++. However, by optimizing the VB application code, the execution speed can be improved, memory usage can be reduced, and the demand for system resources can be reduced.

During the development of the endoscopy case management workstation, some optimization methods are adopted:

D Select the best data type

There are many data types in VB, each with a specific purpose and space requirements. Which type is best depends on the maximum range required by the variable and whether there are requirements for accuracy.

'@ Only use variable data types (Variant) when needed'

Variable data types are quite flexible, but they are very burdensome at runtime. Variable data types occupy 16 bytes regardless of the type of data stored, while they occupy 22 bytes plus the length of the string when storing character information. If variables are not explicitly declared, all undeclared variables will use variable types.

③ Use default attributes

Most controls have default attributes. If you need to modify the default attribute value at runtime, you only need to reference the control name when assigning a value. The default attribute of the Label control is Caption, the default attribute of the Text control is Text, and the default attribute of the Pricture control is Picturea.

④ Remove useless code

Useless code is easy to appear in applications. If a control is deleted without deleting the code unrelated to it, the code will be placed in the common segment function of the application. Although useless code does not occupy execution time, it increases the size of the application. The larger the application, the more frequently it will be swapped out of memory, thereby affecting the speed of the entire application.

Rencheng Medical has been mainly engaged in the repair of color ultrasound endoscopes for more than ten years and has rich experience in knowing the problems that hospitals want to solve. The functional modules have wide applications, strong technical research and development capabilities, reasonable market planning layout, positive after-sales service response, and abundant agency profit returns. Rencheng's after-sales service and technical support system is responsible for providing technical guidance, support, and tracking services to each franchisee, and opening a 24-hour free after-sales service hotline to serve you at any time.

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