He then moved to Sankara Nethralaya Chennai India’s largest eye hospital and underwent 24 months fellowship program in General Ophthalmology and trained under prominent ophthalmologists like Dr K Ravishankar, Dr T S Surendran, Dr PremaPadmanabhan, Dr G Sitalakshmi, and  Dr L Vijaya. During fellowship period actively participated in various international and national conferences.

Further in pursuit of academic excellence, in the year 2008, after successfully clearing the examination he was conferred with FRCS (Glasgow) .

As a recognition of exception performance, was recognised as the Best Associate Consultant for the year 2008 and conferred the Dr TLK Row Endowment award.

He further got trained under Dr PremaPadmanabhan ( Director Cornea and Refractive Services, Chennai)  for Refractive surgery.

In 2009 he was transferred to Sankara Nethralya Kolkata. He was given the task of establishing the Sankara Nethralaya Lasik centre in 2011. He has been credited with many firsts like:
First to use of femtosecond Lasik i.e bladeless Lasik in EAST.
First to use Multifocal Toric IOL in EAST
First to start Implantable Collamer Lens (ICL)
Since 2014 Dr Sagar is attached with BB eye foundation and routinely doing  standard lasik , femtolasik and implantable collamer lens with immense success.

Presentations & publications
1) In AIOS annual conference 2002 at Ahmedabad, made a presentation on “Disinfection techniques & Management of Biomedical Waste” in an instruction course on ‘hospital management’.2) Poster presentation on ” A rare case of infiltrated optic neuropathy” at 52^nd TNOA conference at Tirunelveli in August 2004.

3) Paper presentation on “Comparison of monofilament Nylon vs Vicrylfor wound closure in Phacoemulsification  combined with trabeculectomy” at AIOS 2005

4) Poster presentation on ” Comparison of SRK II and SRK T formulae for high myopes”  at APAO 2006 held at Singapore

5) Poster Presentation on ” Potential acuity meter – Is it potential correct”  at the AIOS 2007

6) Poster presentation on  ” Phacoemulsification in eye with uvealcoloboma” at SERI 2007 held at Singapore

7) Conducted instruction courses on refractive surgery and Implantable collamer lens in OSWB (state conference West Bengal )  in 2012 -13.

8) Oral Presentation in IIRSI 2014 in july 2014 on toricioland lasik complications

9) Presentation in Patna in sept 2014 on Prostaglandin Analogues – Current concepts

10) Conducted  Instruction course on refractive surgery in state conference (OSWB)  in nov 2014 in Kolkata

11) Invited as a guest speaker to deliver a lecture on secondary glaucomas in Howrah Ophthalmic society meeting on 20 thnov 2014

Publications

1) Technique for removing OVD to prevent CBS .Sagar Bhargava, Ashok Rangarajan, Mona Bhargava  , Journal of Cataract & Refractive Surgery , Volume 34 , Issue 9 , Pages 1422 – 1422

2) Coaxial microincision cataract surgery versus conventional coaxial cataract surgery .Sagar Bhargava, Ashok Rangarajan  Journal of Cataract & Refractive Surgery , Volume 34 , Issue 7 , Pages 1055 – 1055

3) Comments on lift and crack technique for risky cataract cases – Sagar Bhargava, Mona Bhargava. Cataract Refract Surg. 2010 Sep;36(9):1621-2; author reply 1622-3.

4)Intra-bleb hematoma and hyphema following digital ocular compression. Bhargava S, Choudhari NS, Vijaya L. Oman J Ophthalmol. 2014 Jan;7(1):22-4