theeran kaur gill, guo hou loo, guhan muthkumaran, nik ritza kosai.  (2025).  posterior membranous tracheal injury during mckeown oesophagectomy. a case report with literature review..  - frontiers in oncology.  1 - 6. 

firdaus che ani, guo hou loo, richelle huey bing chua, kok-yong chin, nik ritza kosai.  (2025).  integrating cruroplasty with laparoscopic sleeve gastrectomy: a strategy to mitigate gerd symptoms in obese patients. a randomized control trial.  - langenbeck's archives of surgery.  1 - 7. 

wan izzah wan jaffar, guo hou loo, fazarina mohammed, deborah chia hsin chew, guhan muthkumaran and nik ritza kosai.  (2025).  case report: rare case of signet ring gastric adenocarcinoma with rectal metastasis.  - frontiers in oncology.  1 - 6. 

wei soon pang, guo hou loo, guo jeng tan, mardiana mardan, reynu rajan, & nik ritza kosai.  (2024).  comparative evaluation of early diabetic outcomes in southeast asian patients with type 2 diabetes mellitus undergoing roux-en-y gastric bypass (rygb) verssus sleeve gastrectomy (lsg).  - scientific reports.  1-7. 

jun sen chuah, jih huei tan, mohamad adam bujang, koon khee chan, nik ritza kosai.  (2024).  transcutaneous electric nerve stimulation of acupuncture points improves tolerance in adults undergoing diagnostic upper gastrointestinal endoscopy - a single center, double-blinded, randomized controlled trial.  - surgical endoscopy.  3279 - 3287. 

asif sukri, alfizah hanafiah, nik ritza kossai, mohamad aznan shuhaili, mustafa mohammed taher, raja affendi raja ali.  (2024).  perbandingan pengekspresan antigen kluster pembezaan dalam subjenis tumor dan darah periferi pesakit kanser gaster .  - sains malaysiana.  3253 - 3262. 

alfizah hanafiah, asif sukri, nik ritza kosai, mohamad aznan shuhaili, mustafa mohammed taher & raja affendi raja ali.  (2023).  immunophenotyping of gastritis, gastric ulcer and gastric cancer using a cluster of differentiation (cd) antibody microarray.  - sains malaysiana.  187-197. 

sivesh kk., sheraz rm., pritam s., ewan ag., on behalf of oeasophagogastric anastomosis audit group.  (2020).  the influence of the sars-cov-2 pandemic on esophagogastric cancer services: an international survey of esophagogastric surgeons.  - diseases of the esophagus.  1-12. 

reynu rajan, mohammed sam-aan, nik ritza kosai, mohamad aznan shuhaili, tee sze chee, ajay venkateswaran, kamal mahawar.  (2020).  early outcome of bariatric surgery for the treatment of type 2 diabetes mellitus in super-obese malaysian population.  - journal of minimal access surgery.  47-53. 

loo guo hou, anusha prabakaran, reynu rajan, fatimah binti mohd nor, nik ritza kosai.  (2019).  concurrent bariatric surgery and surgical resection of massive localized lymphedema of the thigh. a case report..  - annals of medicine and surgery.  53-56. 

solomon raj vasudayan, guo hou loo, guhan muthkumaran, nik ritza kosai .  (2025).  gastric perforation secondary to a hyperinflated intragastric balloon: a case report and management approach.  - cureus.  1 - 7. 

richelle huey bing chua, guo hou loo, nani hl, guhan muthkumaran, nik ritza kosai.  (2025).  bariatric surgery as an adjunctive treatment for failed back surgery syndrome: a case report highlighting a multidisciplinary approach.  - cureus.  1 - 6. 

wan izzah wan jaffar, guo hou loo, fazarina mohammed, deborah chia hsin chew, guhan muthkumaran and nik ritza kosai.  (2025).  case report: rare case of signet ring gastric adenocarcinoma with rectal metastasis.  - frontiers in oncology.  1 - 6. 

muhamad zulhilmi akmal zainuddin, jemaima che hamzah, nik ritza kosai nik mahmood, cheng teck chee, mae-lynn catherine bastion.  (2025).  nutritional optic neuropathy: bariatric surgery gone wrong.  - cureus.  1 - 12. 

solomon raj vasudayan, guo hou loo, mogaraj sellapan, geok chin tan, nik ritza kosai.  (2025).  small bowel volvulus secondary to meckel’s diverticulum with meso-diverticular band: a case report and literature review.  - cureus.  1 - 5. 

hanafiah harunarashid, farrah-hani imran,, nik ritza kosai.  (2017).  chapter 17: skin incisions.  - at a glance series (oxford, england).  38-39. 

nik ritza kosai nik mahmood.  (2025).  kaedah belon bantu atasi masalah obesiti.  - berita harian.  . 

nik ritza kosai nik mahmood.  (2025).  belon telan allurion jadi pilihan.  - harian metro.  . 

halina md. noor, nik ritza kosai nik mahmood.  (2025).  rawatan obesiti tanpa pembedahan, parut.  - utusan malaysia.  . 

nik ritza kosai nik mahmood.  (2025).  bariatrik bukan jalan pintas untuk cantik.  - sinar harian.  . 

asif sukri, alfizah hanafiah, nik ritza kossai, mohamad aznan shuhaili, mustafa mohammed taher, raja affendi raja ali.  (2024).  perbandingan pengekspresan antigen kluster pembezaan dalam subjenis tumor dan darah periferi pesakit kanser gaster .  - sains malaysiana.  3253 - 3262. 

nik ritza kosai, jeffrey bronks, loo guo hou.  (2025).  scalable solutions for mid-tier obesity: revisiting the role of igbs.  - omnihealth practice.  . 

wan ahmad atarmizi, nik ritza kosai nik mahmood.  (2025).  why bariatric surgery is classified as a treatment for disease, not an easy way out.  - sinar daily.  . 

nik ritza kosai nik mahmood.  (2025).  kaedah belon bantu atasi masalah obesiti.  - berita harian.  . 

soon li wei, nik ritza kosai nik mahmood, norlela sukor.  (2025).  esg: a breakthrough option for weight loss, say hctm experts.  - bfokus.  . 

rafe'aton md. ali, nik ritza kosai nik mahmood, loo guo hou.  (2025).  allurion ballon: a medical innovation to treat obesity without surgery.  - fokus bernama.  .