Indian Journal of Ophthalmology

: 2021  |  Volume : 69  |  Issue : 4  |  Page : 1008--1013

Surgical skill assessment rubric for Ahmed glaucoma valve implantation surgery

Manikanta Damagatla1, Rashmi Krishnamurthy2, Sirisha Senthil2,  
1 Academy of Eye Education, L V Prasad Eye Institute; VST Centre for Glaucoma Care, L V Prasad Eye Institute L V Prasad Marg, Banjara Hills, Hyderabad, Telangana, India
2 VST Centre for Glaucoma Care, L V Prasad Eye Institute L V Prasad Marg, Banjara Hills, Hyderabad, Telangana, India

Correspondence Address:
Dr. Rashmi Krishnamurthy
VST Centre for Glaucoma Care, L V Prasad Eye Institute L V Prasad Marg, Banjara Hills, Hyderabad - 500 034, Telangana

How to cite this article:
Damagatla M, Krishnamurthy R, Senthil S. Surgical skill assessment rubric for Ahmed glaucoma valve implantation surgery.Indian J Ophthalmol 2021;69:1008-1013

How to cite this URL:
Damagatla M, Krishnamurthy R, Senthil S. Surgical skill assessment rubric for Ahmed glaucoma valve implantation surgery. Indian J Ophthalmol [serial online] 2021 [cited 2022 Nov 30 ];69:1008-1013
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Full Text

Dear Editor,

Implantation of a glaucoma drainage device is one of the options in the management of complex and refractory glaucoma.[1] In the past, this device was reserved for patients with failed filtration surgeries. However, in current practice, Ahmed Glaucoma Valve (AGV) is used as a primary procedure especially in eyes with high risk of trabeculectomy failure including neovascular glaucoma; Irido-corneal endothelial syndrome; secondary glaucoma due to uveitis; post keratoplasty; and post-vitreo-retinal surgeries.[2] Hence, skill in AGV surgery is crucial for ophthalmology trainees, especially those specializing in glaucoma management. Implantation of AGV is technically challenging with a long learning curve especially for beginners. Currently, the emphasis is on assessing the competency of the learner with less inter personnel variations.[3],[4],[5] Tools have been designed to objectively assess the competency of an ophthalmic trainee for different surgical procedures such as Global Rating Assessment of Skills in Intraocular Surgery (GRASIS)[6]; Objective assessment of skills in intraocular surgery (OASIS)[7]; and Next Accreditation System in Ophthalmology (NSA).[5]

The “International Council of Ophthalmology – Ophthalmology Surgical Competency Assessment Rubric” (ICO-OSCAR) is a standardized, internationally validated tool to teach and to assess beginner's competence in performing surgery. This skill-based rubric allows the trainer to objectively assess the beginner's competency in performing a procedure. It also gives the beginner a tool to better understand one's own performance. To date, rubrics have been produced for adult cataract surgery (extracapsular cataract extraction, small incision cataract surgery, and phacoemulsification),[8] strabismus,[9] lateral tarsal strip,[10] pediatric cataract surgery,[11] trabeculectomy,[12] vitrectomy,[13] anterior approach ptosis surgery,[14] pan-retinal photocoagulation,[15] external dacryocystorhinostomy[16] and pterygium surgery.[17] Many rubrics had also been designed for assessment of different surgeries on simulators in wet-lab[18],[19] No such tool exists for glaucoma drainage devices. In this paper, we describe our method of developing a rubric for Ahmed Glaucoma Valve (AGV) implantation surgery and conducting Face and Content validation. Face validity is the extent to which the rubric serves the aim of the study (assessment of trainee skills) and Content validity is the extent to which the rubric covers all the steps of the surgery.

Modified Dreyfus model of skill acquisition (novice, beginner, advanced beginner, competent, expert)[20] was used to structure this rubric with a numeric value for each level of skill. 'Expert' is the highest level of competence, when a surgery can be performed with intuition, making appropriate modifications as required in the surgical steps. As beginners are not expected to become expert during training, the grading point 'expert' was excluded. Surgical procedure was described stepwise and in detail [Figure 1]. Each step is graded for the level of skill, from novice to competent, based on performance. A description of the performance required for each grade in a step is elaborated. Each grade in each step is given a numeric value starting from novice to competent (1–4). A total of 14 surgical steps and 5 global indices have been described in the rubric. Global variations are included for a few surgical steps (steps 9 and 14: scleral tunnel/track/patch graft) so that the tool can be adapted globally. The trainee is asked to score oneself at each step, and on completion of all steps, the total score helps the trainee surgeon to know the level of competency. The evaluator also scores each step, and the total score of the evaluator and that of the trainee are compared. If a particular step is not done by the trainee, that step is not scored (score = 0). Based on this, the evaluator would be able to discuss the pitfalls of each step and provide specific feedback to the trainee which would make learning more objective and quicker. The trainee can then work on improving on the steps with a low score.{Figure 1}

The rubric was assessed for face and content validity by a group of expert glaucoma surgeons, having over 5-10 years' experience in performing Ahmed Glaucoma valve implantation and training others in this procedure. These surgeons work across the network of our four tertiary eye care centers located in different states of India. They made various suggestions after assessing the initial draft tool, and recommended modifications to certain steps that are followed by different surgeons. Appropriate amendments were made to the rubric and finally drafted.

The surgical skill assessment tool has an important role in objectively assessing the competence of a novice surgical trainee. The systematic evaluation of the level of competency and scoring helps the trainee to acquire appropriate skills, to improve and to master a new surgical technique. The clearly defined steps help the trainer to objectively assess and appropriately guide the trainee, thereby decreasing subjective variations in assessing. Surgical rubric also helps the trainer to clearly communicate the improvements expected from a trainee to become competent with the procedure. Thus, it serves a dual purpose of training and assessment. To the best of our knowledge, no surgical assessment tools are available for Ahmed Glaucoma Valve Implantation surgery. This rubric for AGV implantation not only details various surgical steps but also takes global indices into consideration. These non-surgical professional attributes commonly known as “non-technical skills for surgeons” (NOTSS)[21] take into account various aspects such as situation awareness, decision making, communication and coordination with the surgical team members, and also help trainees to develop leadership qualities. This rubric could be developed into standardized tool for training and assessing a novice surgical trainees' competence in performing AGV implantation surgery. The next steps would be to further test the rubric at a multicentre level for further validation and refinement, to standardize it for global implementation.

Few steps for example Antimetabolite use were not included in the rubric as trainees are not expected to make any modifications in the surgery. The study was validated by the institutional expert panel but not by international experts. However, care has been taken that all the steps followed globally are incorporated in the final steps. Hence, this tool for AGV surgery can be used internationally to train and assess the surgical skills.


We thank the expert panel for their valuable comments in drafting the rubrics. The expert panel are Dr Sirisha Senthil, Dr Aparna Rao, Dr Swathi Badakere, Dr Ramyashri S, Dr Nikhil S Choudhari, Dr Rohit C Khanna, Dr Siddharth Dikshit, Dr Kiranmaye TVH, Dr Avik Kumar Roy, Dr Nibedita Sahoo, Dr M Vivekananda, Dr Ramani G S.

Financial support and sponsorship


Conflicts of interest

There are no conflicts of interest.


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