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Patients Of Major Head Surgery


Most of the patients who had undergone any major head surgery will require an effective protection of their wound. After surgery, some patients especially post-traumatic injury have a high risk of falling due to neurological impairments, weakness, post-op seizures and agitation or confusion and re-injure their head. This is more important if part of the patient’s skull is removed (craniectomy). Appropriate protective headwear during the acute period post-op can be worn and reduce the chance of injury. While effective protection for the head and face is a priority for these individuals, headwear should also provide unobstructed vision and adequate ventilation, lightweight, cosmetically acceptable and reasonably priced. Providing effective headwear is a problem for many orthotists and the rehabilitation team taking care of individuals who have a high risk of head injury following a fall. Parents, caregivers and clinicians usually opt to use commercial sports helmets or other types of adjustable off-the-shelf headwear. Although commercial helmets are adaptable and relatively inexpensive, a number of features make them generally unsuitable for the disabled population post-operation. The main idea for this protection helmet is to provide a comfortable wear for the patient and reduce risk of injuring the head and wound during inpatient period. In other way, the design should be able to minimize the impact to the head if a fall or knock occurs.


Human brain can withstand 300 to 400 G of impact without either concussion or skull fracture, provided that there is no local deformation of the skull to inflict direct injury. Patients sometimes ha head surgery that needed to remove some part of their skull. This will make impact that brain can withstand lower than original. Thus, the helmet protection for post operative will be needed.

2.1 Review Journal

According to Understanding Head & Neck Trauma by Tony Pan Sanfelipo, the impact that head can withstand is vary from the location that the forces is being exerted. The frontal bone (forehead) can withstand on average, 1,000 to 1,600 pounds of force. The temporo-parietal (sides of head) bones can tolerate around 700 to 1,900 pounds of force. The back of the skull can handle around 1,440 pounds of force. The bones of the face and cheek are less tolerant, standing forces of only 280 to 520 pounds. From this, we can see that the impact that head can withstand is differ from the impact that brain can withstand. Skull is a very strong bone in our skeletal system. But, caution step also needed to be done especially after the head operation.

According to the Journal of Prosthetic and Orthotic entitled “The Use of Postoperative Cranial Orthoses in the Management of Craniosynostosis” by William J. Barringer, head helmet or cranial orthoses was being widely used in child rehabilitation after having a head surgery of the problem craniosynostosis that is a condition for cranial deformity that can be directly related to the premature closure of cranial sutures. According to the writer, the cause of the problem is still unknown. While in the other Journal of Prosthetic and Orthotic entitled “An Overview of Positional Plagiocephaly and Cranial Remolding Orthoses” by Deanna Fish and Dulcey Lima, said that plagiocephaly is a condition of abnormalities of baby head due to pre-natal and post-natal forces exerted to the head of the baby makes the baby head look weird. The causes of these problem are varied like the head could be shape like that before birth (that is still in the womb), the position of the baby during sleep that make some deformation force, the premature birth of the baby and maybe the supine position of the baby during daytime also can cause this problem.

Both of these problems involve head remodification. For plagioencephaly, the method to remodel back the head is by using a head helmet or cranial remolding orthoses. It was being called “Cranial remolding techniques”. This technique was being applied by cover all the areas that need to be curb by a material and allows space in areas where growth is to be encouraged to promote the desired head shape. The material being used to cover the head is often built like head helmet but not as thick as the normal helmet. The example of the material is polypropylene. While craniosynostotis involved head surgery to shape back their head. Often also used as a treatment after the surgery is the head orthoses. According to William J. Barringer, the patient that used the orthoses after the surgery more likely to have the shape of the head almost regained normal. According to the author, based on the survey that he had made, he concluded that many advantages that the patient can get by putting on these ortoses after head surgey for craniosnostotis patients like it appears that orthoses can be used to extend the correction gained in surgery or to protect against regression to the presurgical deformit. It is also apparent that age, severity of deformity, type of deformity, surgical procedure, physician preference, and bone healing play important roles in determining the overall outcome and decision-making. According to the author also, there are many ways, material and shape of the head orthoses can be made. An example is a head orthoses that using bends materials that attach the part together.

While the authors for the “An Overview of Positional Plagiocephaly and Cranial Remolding Orthoses” article said that many different orthotic designs have been developed during the last 20 years to effectively address this patient population. Whether the design is active or passive in nature, rigid or flexible, hinged or circumferential, the basic principle of all cranial remolding orthoses is to create a pathway for symmetrical growth to occur. The authors also quoted that there are several ways to make the cranial orthoses. A cast or three-dimensional image of the infant's head is acquired. The model is modified to full or partial symmetry, depending upon the severity of the condition, design of the orthoses, and protocols of the treating orthotist. Mild and moderate asymmetries may be modified to full symmetry while severe deformations may require progressive adjustments to the inner surface of the orthoses to obtain full symmetry throughout the course of the treatment program. Orthotic designs including chinstraps are likely to be less intimate at the initial fitting, allowing for normal growth to follow the internal contours of the orthoses. To date, there is no evidence that any one orthotic design provides better outcomes than another. Symmetrical growth is achieved by consistent evaluation and adjustments to the orthoses based upon the child's head shape and growth patterns. Translational movements of the cranial bones are to be expected and frequent evaluation will ensure total contact over prominent areas and provide areas of relief over depressed areas. Circumferential growth is accommodated by the removal or recontouring of material and additional material may be strategically added to provide total contact and to stabilize the orthoses on the infant's head. It is extremely important for the orthoses to be thoroughly cleaned each day to prevent bacterial build-up and problems with scalp rashes. Air holes are commonly added to help dissipate heat as well as to assist in the evaluation of the fit of the cranium to the inner surface of the orthoses.

Due to it’s functional as regain head shape, the cranial orthoses model had to be some sort of medical device that should not affect the patient in bad ways. The U.S. Food and Drug Administration (FDA) has certain aspect that cranial remodeling orthoses and other medical device manufacturer had to pass before patients can used their model in United State of America. To obtain clearance, manufacturers are required to explain the design of the product(s), how they are intended to work, and how they are manufactured. They are also required to describe the treatment protocols, provide appropriate labeling, and market the devices for only approved uses. All manufacturers must undergo regular FDA audits of their facilities and must comply with the Medical Device Reporting requirements to report any device failure that could lead to serious injury or death. This is being taken from Journal of Prosthetic and Orthotic entitled “FDA Regulation of Cranial Remodeling Devices” by Timothy R. Littlefield.

2.2 Disadvantages of The Older Design

While cranial remolding orthoses is for children, others research had been done to make cranial orthoses for needed patient after head surgery whether the patients is children or adults. The design should be lightweight, effective and protect the head better. According to Journal of Prosthetic and Orthotic entitled “Development of a Modular Design, Custom-Fitted Protective Helmet” by Steve Ryan,Greg Belbin, Mendal Slack, Stephen Naumann and Rod Moran, stated that the new design by them trough this project should be assign because there are many disadvantages of the already have design like:

Commercial helmets protect the cranium but leave the facial area, particularly the chin and oral structure, vulnerable. Commercial face shields could provide the extra protection, but they may impede vision and add to a "caged in" feeling. In addition, because of a face shield's remote placement, it could contribute to neck injury if caught on a stationary object during a fall.

Usually commercial helmets are designed with ventilation slots and liner cooling paths, which are conduits for forced air movement through the helmet. Cooling occurs as the wearer moves. This form of ventilation is inefficient for the disabled population since, for the most part, they move at or below normal walking speed.

Suspension in commercial headwear is provided primarily by a chin cup attached to the helmet by straps, which are tightened to prevent helmet movement. Constant pressure applied to the chin could lead to orthodontic problems, particularly in the growing child.

Because of these, they proposed new design for the cranial orthoses. Their design is mainly focused of three parts of the head that are anterior section, posterior section and chin protector. Each part are fabricated from polyethylene foam with the exterior is hard polyethylene while the anterior is low-density polyethylene foam. They fabricate the orthoses and made a survey of it. The result from the survey is the research helmet was found to be an orthotic device that could be readily dispensed in a clinical setting in one appointment. On average, it required two hours to measure, evaluate and fit a subject. The project orthotists felt that, with experience, the helmet could be fitted in less than two hours except in cases where special modifications were required. The orthotists remarked on the ease with which they could dispense the helmet using the specially designed jigs and fixtures provided. No major technical problems or mechanical failures were identified during the helmets' post-trial evaluation. This is being sited on their article.

2.3 Summary

Last but not least, we proposed the title of our clinical project “Post-OP Protection Helmet” to help patients head after surgery minimize the risk of reinjuring their head due to possible fall during acute period. Several factors like Post-traumatic, seizure, confusion, agitation and imbalance can lead to knocking their head accidently at the skull defect site. With this device, patient can protect their head especially. For our design, we applied the basic concepts of engineering like the concepts of energy absorption and load distribution and also biomechanics application.

Chapter 3: Methodology

3.1 Technique used

There are two ways of technique we performed our task. Firstly, we used AutoCAD Engineering software to design the shape of the helmet. We used this software because it can perform the shape clearly and make the 3D dimension. We have to consider the convenience and the cosmetically acceptable criteria during the design process.

Next, we do the research on the materials for protection helmet which will be manufacture. We had referred to the journals and related reference books. The material must satisfy the ASTM standard, such as tensile strength, abrasive resistance, young modulus and others. In addition, the material should easily fabricate and lower cost.

The method we use to build the outer shell is plastic injection molding, this method is use the plastic from pellets or granules and heat it until melt. Then we push the melt into a split-die mold where can cool it at the shape design. Finally we open the mold and take out the part, the cycle is repeating. The wall thickness is a important key to use under this method, because the thick wall will take more time to cool and it will have greater the shrinking , but if the wall is thin so it will cool faster, the less shrinking. And we will use a drilling machine to make some hole to let the air can float out from the protective helmet.

For the data collection, we compare mechanical properties, physical properties, thermal properties and chemical resistance between several polymers. From the comparing, we had chosen the polycarbonate as the outer surface of the POST-OP Protection Helmet because they are easily worked, moulded, thermoformed and good in mechanical properties. However, for the inner padding, we choose EVA (Ethylene vinyl acetate) because light weight, easy to mould, odorless, glossy finish, and cheaper compared to natural rubber. It is good for deceleration impact energy.

3.2 Properties of the Material

Properties of the outer shell


0.0397-0.0484 lb/in3

Water Absorption

0.05-0.7 %

Hardness, Rockwell R


Tensile Strength, Ultimate

5800-12500 psi

Charpy Impact

20.5-37.6 ft-lb/in2

Oxygen Index


Processing Temperature


Table 3.1

Properties of the inner padding

Specific Density






IMPACT (IZOD ft. lbs/in)




Table 3.2

Figure 3.1 Plastic injection molding machine

The material we choose to use for the outer shell is Polycarbonate Resin Thermoplastic 3414(40%GF). The properties of the material below this table:

Young’s modulus, psi

Shear modulus, psi

Mass density,lb/in3

Thermal exp coef, 1in/in/F

Ultimate tensile,psi






Ultimate compressive, psi

Ultimate shear,psi

Thermal conductivity, Btuin/hrft2F

Specific heat,Btu/lb/F





Table 3.3

This material has good conductivity compare to other material like Polycarbonate Resin Thermoplastic 3413 (30%GF). So we choose this material.

3.3 The Design of the Protection Helmet

Figure 3.2: Top view sutures Figure 3.3: Side view sutures

From the picture above, that was several type of wound, the design of the protective helmet should not contact with the wound part and provide ventilation for air circulation to faster the wound healing. The special of our design is the professionals working with patients needing head coverage after surgery can place positioning pads around the inside of the clear shell. In an area of recent surgery example, pads would be place around a wound or surgical site to keep helmet shell elevated and away from the affected area. Clear polycarbonate shell, edged with soft foam is then lined with self adhesive foam pads in various thicknesses, and ventilation holes are added. Suggestions for placement of the pads are included with the helmet. The helmet is made from thermoplastics polymer material that lightweight, lower cost, and has many high mechanical properties. The benefit of the transparent outer shell design is allows better supervision of the underlying wound and skull defect. The material is crucial factor to this helmet because patient with head surgery need something that can feel very comfortable to their head. Material with least dense with be an awesome choice for them. The helmet also needs to have good mechanical properties to increase wear resistance. The helmet should be not has low strength and low hardness. The needed for these higher mechanical properties is to give protection of the head of the patients in abrasive environment. We should know that patients can be very stressful and lost control after a major head surgery. This is especially true in traumatic brain injury patients. They can bang their head to walls and the helmet should resist the forces from the banging in order to protect the head. So, in overall, the both material for inner and outer parts of the helmet were made from a very good mechanical properties polymers.

Chapter 4: Result

4.1 Physical Architecture

The design and chosen material was refer to functional, reliable, safety and costly. As we approached the data technique given by the ASTM standard this outcomes design would give very important benefits to us. Besides that, this most suitable material is to reduce the percentage of injury by the patient.

The design we come out also very important, the outer surface material is hard, and the inner is comfortable and can absorb the high impact. The outer surface of the protection helmet using clear polycarbonate shell is easily to fabricate by the engineers. This outer surface gives the superior safety effectiveness to the patient.

Figure 4.1 : Feature of Post-OP Protection Helmet Design

4.2 Logical Architecture

From this post-Op helmet, the patient should refer by their doctor what kind of shape or where to put the EVA (Ethylene vinyl acetate) for inner surface on helmet as not to contact with the wound. The inner surface had a hollow part to avoid contact to the wound.

The ventilations on the outer helmet help the air going in to contact the surface wound. This would help the wound healing more fasters. This also makes the patient head not feel hot and trapped with unwanted air thus make the head’s skin get irritated.

On the other hand, this helmet will give the amazing comfort, rugged durability, lightweight safety and stay-put in custom fit. The helmet would work great for patients post-surgery and the compliance is would be wonderful.


Our design has many benefits to post-surgery patient throughout the world based on the advantages like:

The helmet is made from thermoplastics polymer material that lightweight, lower cost, and has many high mechanical properties. The material is crucial factor to this helmet because patient with head surgery need something that can feel very comfortable to their head. Material with least dense with be an awesome choice for them. The helmet also needs to have good mechanical properties to increase wear resistance. The helmet should be not has low strength and low hardness. The needed for these higher mechanical properties is to give protection of the head of the patients in abrasive environmentWe should know that patients can be very stressful and lost control after a major head surgery. This is especially true in traumatic brain injury patients. They can bang their head to walls and the helmet should resist the forces from the banging in order to protect the head. So, in overall, the both material for inner and outer parts of the helmet were made from a very good mechanical properties polymers.

The design of the helmet also makes a very good properties and advantage for the patient. The design of the helmet is ventilation, cosmetic acceptable and functional.

It views same shape as our human head shape. So that, the patient can proceeds their normal life without . Strap was adjustable, in case of emergency, the strap can be easily remove and unlock. At the ear part, the part was uncover, so it was convenience to hearing and very comfortable.

CHAPTER 6: Discussion

The Post –op protection helmet is use to protect the patient from head injury after head surgery. Some of these have a high risk of falling due to multiple medical complication post – op. Re-bleeding is the major complication and can cause further neurological deterioration.

When the helmet collide something, inside the protective helmet have EVA (Ethylene vinyl acetate), it will absorb the energy produce from the collision and the EVA can increase the time between head and the outer shell collision, so the energy will hit the helmet will decrease and can protect the head from the injury.

And the outer shell will have some holes so inside the protective helmet will ventilate and the patient will feel more fresh and comfortable. The outer shell is colour less is because like can let other people easily to know the head condition, so can confirm inside the protective helmet is safe.


Barringer, William J. (2004). The Use of Postoperative Cranial Orthoses in the Management of Craniosynostosis. Journal of Prosthetic and Orthotic, 4S(16), 56-58. Retrieved September 9, 2009 from

Fish, D. & Lima, D. (2003). An Overview of Positional Plagiocephaly and Cranial Remolding Orthoses. Journal of Prosthetic and Orthotic, 2(15), 37-47. Retrieved September 9, 2009 from http:// www.

Ryan, S., Belbin,G., Slack,M., Naumann, S., & Moran, D. (1992). Development of a Modular Design, Custom-Fitted Protective Helmet. Journal of Prosthetic and Orthotic, 4(4), 213-218. Retrieved September 9, 2009 from jpo/library/1992_04_213.asp

CHAPTER 8: Rehabilitation Medicine Unit

8.1 History

The Department of Rehabilitation Medicine started as a section of the Department of Orthopaedic Surgery in 1965 under the headship of Professor Dr. J.F. Silva. Services provided were general physiotherapy, general occupational therapy and orthopaedic appliances service. The return of UM’s pioneer Rehabilitation Physician from University of London in 1984, Dr. Zaliha Omar became a starting point for the development of rehabilitation services in the UMMC as well as in Malaysia.

The first service to be introduced was the Rehabilitation Medicine consultation service which provided expert consultations in the fields of general rehabilitation. In addition, Rehabilitation Medicine was introduced as a subject in the undergraduate medical curriculum in 1984.

In May 1995, the need to start Masters in Rehabilitation Medicine and Masters in Sports and Rehabilitation Medicine necessitated the shift of the rehabilitation section, from the Department of Orthopaedic Surgery to the Department of Allied Health Sciences and known as the Rehabilitation Sciences Unit. The Department of Allied Health Sciences then comprised of 2 units ie the Biomedical Science Unit and the Nursing Sciences Unit.

By then, the scope of rehabilitation services along with the advancement in technology and increasing patient demand; saw a paradigm shift from being a general rehabilitation service provider to a specialized rehabilitation medicine service provider which emphasized on a multidisciplinary and interdisciplinary team approach. The first such service to be introduced was the Neuromedical Rehabilitation Service in 1991. This was followed by Spinal Rehabilitation (1992), Upper Limb and Hand Rehabilitation (1992) and Burns Rehabilitation (1992). The unit then went on to develop other specialised services and continue to upgrade existing services.

These include Paediatric Neurodevelopmental Rehabilitation (1995), Prosthetic & Orthotic Management Service, Wheelchair Management Service (1995), Amputee Rehabilitation (1996), Sports Rehabilitation (1998), Work Rehabilitation (1998), Wound Management and Diabetic Footcare (1998), Geriatric Rehabilitation (1999), Alternative Approaches to Rehabilitation Medicine (Acupuncture Service) in 1999, Neurosurgical Rehabilitation (2002), Women’s Health (2002), Musculoskeletal Rehabilitation (2003) and Cardiac Rehabilitation (2006).

The Rehabilitation Sciences Unit of the Department of Allied Health Sciences under the headship of Assoc Prof Dr. Zaliha Omar initiated 2 very important academic programmes in the country namely the Master of Sport Medicine and Rehabilitation in 1996 and Master of Rehabilitation Medicine in 1997. The early days of conducting 2 new programmes in relatively unknown fields posed numerous challenges but the unit received excellent support from various parties; other departments within the faculty as well as from the international arena. 

One of the valuable contributions was from Professor Balasubramaniam from the National University of Singapore who was previously Head of Orthopaedic Surgery, Faculty of Medicine, University of Malaya from 1979 – 1982. Professor Bala was appointed Visiting Professor to the unit from 1997 to 2000 and as Chair for Tun Siti Hasmah’s Chair for Rehabilitation and Sport Medicine from 2000 until 2003. The Rehabilitation Medicine Unit was also very fortunate to have collaboration with the University of Melbourne and 13 of its trainees underwent elective training of 6 to 12 months in Melbourne, Australia in various fields in rehabilitation medicine as part of the 4 year masters programme.

The Rehabilitation Sciences Unit produced its first graduates in 2001, and to date have produced 17 rehabilitation physicians in Malaysia.

The unit has also grown, from a one-man show ie Assoc Prof Dr. Zaliha Omar in the 80s and later in 1994 joined by Dr. Tunku Nor Taayah Tunku Zubir who left in 2001, it now has 6 academic staff and 1 trainee lecturer.

The year 2005 saw the retirement of UM’s as well as Malaysia’s rehabilitation medicine icon, Assoc Prof Dato’ Dr. Zaliha Omar from the academic arena. However she still generously contributes her time to teaching and clinical work in UMMC as a visiting consultant.

Current and Future Developments

With the progress and expansion of the unit in both the academic and clinical fields, the Rehabilitation Sciences Unit put up a proposal in 2006 for the formation of the Department of Rehabilitation Medicine, a clinical department which is involved in teaching, clinical service and research.

With the formation of the Department of Rehabilitation Medicine and the formalization of the merger of its academic (FOM) and clinical services (UMMC) it is hoped that the field of Rehabilitation Medicine and its multidisciplinary components is better understood and its image and function more prominent.

Apart from strengthening and optimizing current clinical services, the department also plans to introduce new services as well as collaborate with other departments in the areas of vestibular rehabilitation, pulmonary rehabilitation, chronic pain management, rheumatological rehabilitation, lymphoedema management service and others.

As rehabilitation medicine is a multidisciplinary discipline, the department has put in its long-term planning, academic programmes in the areas of Prosthetics and Orthotics (in collaboration with Department of Biomedical Engineering, Faculty of Engineering, University of Malaya), Occupational Therapy, Physiotherapy and other related fields.

The department currently has 20 trainees in rehabilitation medicine who go through a 4 year clinical master programme which also incorporates a research component.

With the expansion of clinical services and the increasing number of trainees in the Master of Rehabilitation Medicine programme, the department is constantly reinforcing its faculty and other staff members. The department is also very fortunate to be identified for further development in the form of a one-stop comprehensive rehabilitation medicine complex in the 9th Malaysia Plan.

8.2 Introduction of Department of Rehabilitation Medicine

The Department of Rehabilitation Medicine was formed as part of the overall development of Faculty of Medicine and University of Malaya Medical Centre, Kuala Lumpur for the purpose of providing clinical services in rehabilitation medicine and to provide training in the various fields of rehabilitation medicine.

Apart from providing a comprehensive rehabilitation medicine service involving Rehabilitation Physicians, Medical Trainees in Rehabilitation Medicine, Physiotherapists, Occupational Therapists, Nurses and Medical Social Workers, the department is actively involved in the education of Undergraduate and Postgraduate Medical Trainees, Undergraduate Nursing Students, Physiotherapy and Occupational Therapy Students from the Ministry of Health, MARA University of Technology as well as private academic institutions.

Continuing Professional Development of our multidisciplinary team members is a regular activity of the department. Updates in Medical Rehabilitation are organised regularly for our staff as well as relevant parties from outside the UMMC. All categories of staff have ample opportunity to participate in their respective professional development through conferences as well as courses locally and internationally.

8.4 Vision

The vision of the department is to become the centre of excellence in activities for the provision of services, education, training and research in rehabilitation medicine and in all associated specialities.

8.5 Mission

The Rehabilitation Medicine Unit practices multidisciplinary and interdisciplinary team approach for patient management and demand a comprehensive and a holistic care based on the individual needs of a patient.

The department also considers its mission to be the centre for continuing education, training and maintenance of professional standards for Doctors and Health Professionals of various specialities associated with rehabilitation medicine.

To play a catalystic role in research and development of rehabilitation medicine in University of Malaya and the country.

8.6 Services

8.61 Clinical Services

There includes: General Services, Rehabilitation Medicine Consultation, Physiotherapy, Occupational Therapy and Wheelchair Management Service

8.62 Specialized Services

There includes:

Specialty Clinics - Rehabilitation Medicine Consultation

Neuro-surgical Rehabilitation

Neuro-medical Rehabilitation

Diabetic Footcare and Wound Management Consultation

Spinal Cord Injury Rehabilitation

Amputee Rehabilitation

Paediatric Neurodevelopmental Rehabilitation

Geriatric Rehabilitation

Sports Rehabilitation

Upper Limb and Hand Rehabilitation

Burns Rehabilitation

Diabetic Footcare and Wound Management

Orthotics and Prosthetics

Pre-Driving Assessment

Work Resettlement

Psychosocial Rehabilitation


Musculoskeletal Rehabilitation


Women’s Health

Cardiac Rehabilitation

Wheelchair Seating Clinic

Vestibular Rehabilitation

8.7 Support Group Activities

Apart from providing the core rehabilitation services, the Department of Rehabilitation Medicine is also involved in co-ordinating various activities such as the following :

Stroke Support Group

Amputee Support Group

Active Spinal Rehabilitation Camp

Paediatric Support Group

Cerebral Palsy Network

Persatuan Douglas Bader Kuala Lumpur

8.8 Medical Rehabilitation Welfare Fund

In view of the pressing need for financial assistance in purchasing aids and equipment as well as other general needs for the under-privileged patients, the Medical Rehabilitation Fund was established on 8 January 1999. For further information with regards to contribution in monies and kinds to the Medical Rehabilitation Fund, the Operations Chairperson (Mr. Soh Say Beng) can be contacted at 03-79492594.

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