International Conferences & Publications

Selected Publications


  1. Joel YC Cheung, CP Yu, Robert TK Ho, Tweaked GammaPlan for target volume measurement in non-fiducial based images: a simple routine for follow up assessment, Stereotactic & Functional Neurosurgery, Vol. 70, Suppl. 1, 1998, pp. 243-248.

  2. Joel Y. C. Cheung, K. N. Yu, C. P. Yu, and Robert T. K. Ho, Monte Carlo calculation of single-beam dose profiles used in a gamma knife treatment planning system, Med. Phys., Volume 25, Issue 9, 1998, pp. 1673-1675.

  3. Joel Y. C. Cheung, K. N. Yu, Robert T. K. Ho and C. P. Yu, Monte Carlo calculations and GafChromic film measurements for plugged collimator helmets of Leksell Gamma Knife unit, Med. Phys., Volume 26, Issue 7, 1999, pp. 1252-1256.

  4. Joel Y C Cheung, K N Yu, Robert T K Ho and C P Yu, Monte Carlo Calculated Output Factors of a Leksell Gamma Knife Unit, Physics in Medicine and Biology, Volume 44, Number 12, Dec 1999, N247-N249.

  5. Y.C. Cheung, K.N. Yu, C.P. Yu, T.K. Ho, "Quality assurance of stereotactic treatment planning system: implementation of Monte Carlo technique on Leksell Gamma Knife", Proceedings of the VI International Conference on Medical Physics (September 1-4, 1999 Patras Greece), Monduzzi Editore (International Proceedings Division) S.p.A. - Bologna (Italy), 1999, pp. 95-99.

  6. Y.C. Cheung, K.N. Yu, R.T.K. Ho and C.P. Yu, Stereotactic dose planning system used in Leksell Gamma Knife model-B: EGS4 Monte Carlo versus GafChromic films MD-55 Appl. Radiat. Isot., Vol 53, Issue 3, 2000, 427-430.

  7. J.Y.C. Cheung, K.N. Yu, C.P. Yu and R.T.K. Ho, “Dose distributions at extreme irradiation depths of gamma knife radiosurgery: EGS4 Monte Carlo calculations”, Applied Radiation and Isotopes, Volume 54, Issue 3, March 2001, 461-465.

  8. Chung Ping Yu, Joel Yiu Chung Cheung, Samuel Leung, Robert Ho, Sequential volume mapping for confirmation of negative growth in vestibular schwannomas treated by gamma knife radiosurgery, Journal of Neurosurgery (Suppl 3), 93:82-89, 2000.

  9. Joel YC Cheung, KN Yu, Robert TK Ho and CP Yu, Application of EGS4 on Leksell Gamma Unit, Proceedings of the Second International Workshop on EGS, KEK, Tsukuba, Japan, August 8-12, 2000, pp64-73.

  10. YC Cheung, CP Yu, "Identification of Treated Target Points for Parkinsonism on Gamma Knife Follow-up MR Images", Journal of Clinical Neuroscience, Volume 9, Number 2, March 2002, p178-180.

  11. Cheung JY, Yu KN, Yu CP, Ho TK Robert, Choice of phantom materials for dosimetry of Leksell Gamma Knife unit: a Monte Carlo study, Medical Physics, Oct 2002, 29(10) p2260-1

  12. Motohiro Hayashi, Takaomi Taira, Mikhail Chernov, Seiji Fukuoka, Roman Liscak, Chung Ping Yu, Robert T K Ho, Jean Regis, Yoko Katayama, Yoriko Kawakami and Tomokatsu Hori, Gamm knife radiosurgery for cancer pain-pituitary gland-stalk ablation: a multicentrial prospective protocol since 2002, Journal of Neurosurgery, December 2002, Volume 97, Supplement 5, p433.

  13. Hayashi M, Taira T, Chernov M, Izawa M, Liscak R, Yu CP, Ho RT, Katayama Y, Kouyama N, Kawakami Y, Hori T, Takakura K , Role of pituitary radiosurgery for the management of intractable pain and potential future applications, Stereotact Funct Neurosurg. 2003;81(1-4):75-83.

  14. Erica Ho Pik Lai and Samuel Leung Cheong Lun, Impact on the quality of life of patients with arteriovenous malformation during the latent interval between gamma knife radiosurgery and lesion obliteration, Journal of Neurosurgery, December 2002, Volume 97, Supplement 5, p471.

  15. Joel Y.C. Cheung, K.N. Yu, Josie F.K. Chan, Robert T.K. Ho, and C.P. Yu, Dose Distribution Close to Metal Implants in Gamma Knife Radiosurgery: A Monte Carlo study, Medical Physics, July 2003, Volume 30, Issue 7, pp. 1812-1815.

  16. C.P. Yu, Joel Y.C. Cheung, Joise F. K. Chan, Samuel C. L. Leung, Robert T.K. Ho, Prolonged Survival in a Subgroup of Patients with Brain Metastases Treated by Gamma Knife Surgery, Journal of Neurosurgery, Vol. 102 Special Supplement, pp 262, January 2005.

  17. Joel YC Cheung, KN Yu, LETTER TO THE EDITOR: "Dose Distribution Close to Metal Implants in Gamma Knife Radiosurgery: A Monte Carlo Study, Med. Phys., July 2003, Volume 30, Issue 7, pp. 1812-1815", Medical Physics, Volume 32, Issue 5, 1448-1449, 2005.

  18. Joel YC Cheung, KN Yu, Study of Scattered Photons from the Collimator System of Leksell Gamma Knife using the EGS4 Monte Carlo Code, Medical Physics, Volume 33, Issue 1, pp. 41-45, 2006.

  19. Joel Y.C. Cheung, K.N. Yu, Rotating and Static Sources for Gamma Knife Radiosurgery Systems: Monte Carlo Studies, Medical Physics, Volume 33, Issue 7, 2006, pp. 2500-2505.


Congress Presentations

  1. Joel YC Cheung, CP Yu, Robert TK Ho, Tweaked GammaPlan for target volume measurement in non-fiducial based images: a simple routine for follow up assessment, 8th International Leksell Gamma Knife Society, June 22-25, 1997, Marseille, France, #110, pp. 133.

  2. C.P.Yu, Joel Cheung, Robert Ho, Volume Measurement and Simulated Dose Plan using Gamma Plan Based Frameless Technique, 9th International Leksell Gamma Knife Society, November 8-11, 1998, Hong Kong, SAR., pp. 91.

  3. C.P.Yu, Robert Ho, Joel Cheung, Palliation for Advanced Brain Metastases by the Gamma Knife: A Minimally Invasive Approach, 9th International Leksell Gamma Knife Society, November 8-11, 1998, Hong Kong, SAR., pp. 36.

  4. JYC Cheung, RT Ho, CP Yu, Quality Assurance of Stereotactic MR Images: Application of Non-Fiducial Based Technique, 4th International Stereotactic Radiosurgery Society Congress, 23-26 February 1999, Sydney, Australia, #084, pp. 97.

  5. JYC Cheung, PK Yu, RT Ho, CP Yu, Effects on Output Factors using Phantoms of Different Materials: EGS4 Monte Carlo Calculations on Leksell Gamma Knife (Model-B), 4th International Stereotactic Radiosurgery Society Congress, 23-26 February 1999, Sydney, Australia, #087, pp. 98.

  6. Joel Yiu Chung Cheung, Robert TK Ho, CP Yu, "Spreadsheet for Target Points Determination of Parkinson;s Disease: Gamma Knife Radiosurgery", The 3rd Congress of the Asian Society for Stereotactic, Functional and Computer Assisted Neurosurgery, June 13-16, 1999, Swiss Grand Hotel, Seoul, Korea, GS-I-10.

  7. Joel Yiu Chung Cheung, Robert TK Ho, CP Yu, "Experience in Treating Lesions at Extreme Position: Gamma Knife Radiosurgery", The 3rd Congress of the Asian Society for Stereotactic, Functional and Computer Assisted Neurosurgery, June 13-16, 1999, Swiss Grand Hotel, Seoul, Korea, GS-X-7.

  8. Joel Yiu Chung Cheung, CP Yu, Robert TK Ho, "Algorithm of Simulated Gamma Knife Dose Plan and Applications", The 3rd Congress of the Asian Society for Stereotactic, Functional and Computer Assisted Neurosurgery, June 13-16, 1999, Swiss Grand Hotel, Seoul, Korea, P-I-1.

  9. YC Cheung, KN Yu, CP Yu, TK Ho, "Quality assurance of stereotactic treatment planning system: implementation of monte carlo technique on leksell gamma knife", VI International Conference on Medical Physics (Patras Medical Physics 99), Patras, Hellas, 1-4 September 1999, pp. 22.

  10. CP Yu, Joel YC Cheung, S Leung, Robert TK Ho, “Sequential Volume Mapping (SVM) Confirms Negative Growth in Gamma Knife Treated Acoustic Neuromas”, 10th International Meeting of the Leksell Gamma Knife Society, The Resort at Squaw Creek in Squaw Valley, Squaw Valley, California, USA, 14-17 April 2000, pp. 10.

  11. YC Cheung, RTK Ho, CP Yu, KN Yu, “Gamma Knife Simulation”, 10th International Meeting of the Leksell Gamma Knife Society, The Resort at Squaw Creek in Squaw Valley, Squaw Valley, California, USA, 14-17 April 2000, pp. 131.

  12. YC Cheung, CP Yu, RTK Ho, “Identification of Treated Target Points for Parkinsonism on Gamma Knife Follow-up MR Images”, 10th International Meeting of the Leksell Gamma Knife Society, The Resort at Squaw Creek in Squaw Valley, Squaw Valley, California, USA, 14-17 April 2000, pp. 132.

  13. Joel YC Cheung, KN Yu, Robert TK Ho and CP Yu, “Applications of EGS4 on Leksell Gamma Unit”, Second International Workshop on EGS, Radiation Science Center, KEK, High Energy Accelerator Research Organization, 1-1, Oho, Tsukuba, Ibaraki, 305-0801 Japan, 8 -12 August 2000, pp9.

  14. YC Cheung, KN Yu, RTK Ho and CP Yu, Gamma Knife Simulation, Poster Exhibition: Research Frontiers at CityU, City University of Hong Kong, 28 March - 1 April 2001.

  15. Joel Cheung, CP Yu, Robert Ho, The development of web based database for gamma knife radiosurgery, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p187.

  16. Joel YC Cheung, CP Yu, Robert TK Ho, Kaplan-Meier Survival Curve for Gamma Knife Treated Metastases, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p188.

  17. Joel YC Cheung, Robert Ho, CP Yu, A quick access phantom for angiography in gamma knife radiosurgery, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p189.

  18. Samuel Leung, Y L Cheung, CP Yu, Robert Ho, Joel Y C Cheung, Distortion free digital subtraction angiograms used in gamma knife radiosurgery, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p191.

  19. CP Yu, Joel Y C Cheung, Josie Chan, Samuel Leung, Robert T K Ho, Hearing preservation and symptom control for intra-canicular vestibular schwannomas (vs) treated by gamma knife surgery (gs), 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p26.

  20. Robert Ho, CP Yu, Joel Cheung, Facilitation of the “micro- Gamma Surgery“ Approach with the Model C-APS Leksell Gamma Knife - a study comparison of dose homogeneiity using a single isocentre with the 18mm collimator and multi- multiple isocentres (>15) with the 8 mm and 4mm collimators, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p115.

  21. Robert TK Ho, Joel Y C Cheung, CP Yu, The use of APS in Hong Kong, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p116.

  22. Samuel Leung, CP Yu, Erica Ho, Protection of Rebleeding after Gamma Knife Radiosurgery for AVM, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p214.

  23. Motohiro Hayashi, Seiji Fukuoka, Roman Liscak, Chung Ping Yu, Robert T K Ho, Jean Regis, Tomokatsu Hori, Gamm Knife Surgery for Cancer Pain (Pituitary Stalk Targeting): A Multicentrial Prospective Protocol since 2002, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p226.

  24. Erica Ho, Samuel Leung, Impact on AVM patients Receiving Gamma Knife Before Obliteration, 11th International Meeting of the Leksell Gamma Knife Society, Prague, Czech Republic, May 12-16, 2002, p211.

  25. CP Yu, Joel Y C Cheung, Robert T K Ho. Total management of acoustic neuromas: Towards zero mortality and morbidity. 7th Asian Oceanian International Congress on Skull Base Surgery. Taipei, April 2004.

  26. Joel Y.C. Cheung, C.P. Yu, Robert T.K. Ho, The Influence of Implant Objects in Gamma Knife Radiosurgery, 12th International Meeting of the Leksell Gamma Knife Society, Vienna, Austria, May 2004, p 100.

  27. Joel Y.C. Cheung, C.P. Yu, Robert T.K. Ho, The Development Of Low Cost and Efficient Mass Storage System for Gamma Knife Patient Records, 12th International Meeting of the Leksell Gamma Knife Society, Vienna, Austria, May 2004, p 205.

  28. Joel Y.C. Cheung, C.P. Yu, Robert T.K. Ho, Positional Error Estimations and Remedial Procedures in the Gamma Knife B, 12th International Meeting of the Leksell Gamma Knife Society, Vienna, Austria, May 2004, p 207.

  29. Joel Y.C. Cheung, C.P. Yu, Robert T.K. Ho, Assessment of Gamma Knife Follow Up Patients with Multiple Metastases using GammaPlan v3.x, 12th International Meeting of the Leksell Gamma Knife Society, Vienna, Austria, May 2004, p 277.

  30. Joel Y.C. Cheung, C.P. Yu, Robert T.K. Ho, The Refinement of the 8mm Collimator Helmet Profile on Leksell Gamma Knife, 12th International Meeting of the Leksell Gamma Knife Society, Vienna, Austria, May 2004, p 286.

  31. C.P. Yu, Joel Y.C. Cheung, Josie F. K. Chan, Samuel C. L. Leung, Robert T.K. Ho, Long Survival (>= 24 Months) is Possible in a Subgroup of Brain Metastasis Patients Treated by Gamma Knife, 12th International Meeting of the Leksell Gamma Knife Society, Vienna, Austria, May 2004, p 166.

  32. Joel Y. C. Cheung, C. P. Yu, Robert T. K. Ho, The Use of T2 Weighted MRI for Post Gamma Knife Follow-ups, 7th International Stereotactic Radiosurgery Society Congress, Sep 2005, P1-20.

  33. Joel Y. C. Cheung, C. P. Yu, Robert T. K. Ho, The Study of Dose Enhancement Close to Platinum Implants for 4, 8, 14 and 18 mm Collimator Helmets in the Gamma Knife Surgery, 7th International Stereotactic Radiosurgery Society Congress, Sep 2005, P2-37.

  34. C. P. Yu, Joel Y. C. Cheung, Josie F. K. Chan, Samuel Leung, Robert T. K. Ho, Gamma knife radiosurgery for large volume brain metastases: Acceptable Volume Response Rate with Marginal Increase in Toxicity, 7th International Stereotactic Radiosurgery Society Congress, Sep 2005, P1-47.

  35. Vasu Ganesan, Rami Mehrem, John Fenner, Lee Walton, Monte Carlo Simulation for Gamma Knife Radiosurgery using the Grid, 7th International Stereotactic Radiosurgery Society Congress, Sep 2005, OS12-2. (Acknowledgement: J Cheung)

  36. C.P Yu, M.D., Joel Y.C. Cheung, Ph.D., Josie F.K. Chan, B.N., Robert T.K. Ho, M.D., Samuel C.L. Leung, M.D., Christopher Y.F. Poon, M.D., Erica P.L. Ho, B.N., Incidence, Risk Factors, and Pattern of Swelling of Acoustic Neuromas Tumor after Gamma Knife Surgery: A Logistic Regression Analysis, 13th International Meeting of the Leksell Gamma Knife Society, Seoul, Korea, May 21- 25, 2006, BT4-G2.

  37. Joel Y.C. Cheung, Ph.D., C.P Yu, M.D., Josie F.K. Chan, B.N., Robert T.K. Ho, M.D., Samuel C.L. Leung, M.D., Christopher Y.F. Poon, M.D., Erica P.L. Ho, B.N., The Reconstruction of Missing Gamma Knife Fiducials in DSA Images, 13th International Meeting of the Leksell Gamma Knife Society, Seoul, Korea, May 21- 25, 2006, PS-PH4.

  38. Christopher Y.F. Poon, M.D., Joel Y.C. Cheung, Ph.D., C.P Yu, M.D., Josie F.K. Chan, B.N., Robert T.K. Ho, M.D., Samuel C.L. Leung, M.D., Erica P.L. Ho, B.N., The Importance of 4? Photon Emission Solid Angle in Gamma Knife Spectra Simulations, 13th International Meeting of the Leksell Gamma Knife Society, Seoul, Korea, May 21- 25, 2006, PS-PH7.

  39. Joel Y.C. Cheung, Ph.D., C.P Yu, M.D., Josie F.K. Chan, B.N., Robert T.K. Ho, M.D., Samuel C.L. Leung, M.D., Christopher Y.F. Poon, M.D., Erica P.L. Ho, B.N., The Calculation of Follow-up Tumour Volumes using the Imagetool, 13th International Meeting of the Leksell Gamma Knife Society, Seoul, Korea, May 21- 25, 2006, PS-PH20.

  40. C.P Yu, M.D., Joel Y.C. Cheung, Ph.D., Josie F.K. Chan, B.N., Robert T.K. Ho, M.D., Samuel C.L. Leung, M.D., Christopher Y.F. Poon, M.D., Erica P.L. Ho, B.N., An Effective Plugging for the Gamma Knife Surgery of Pituitary Adenomas, 13th International Meeting of the Leksell Gamma Knife Society, Seoul, Korea, May 21- 25, 2006, PS-BT11.

  41. Josie F. K. Chan, B.N., C.P. Yu, M.D., Joel Y. C. Cheung, Ph.D., Robert T. K. Ho, M.D., Use of Slotted Front Piece (Single Front Post) to Avoid Helmet/Post Collision for Targets at Extreme Locations, 13th International Meeting of the Leksell Gamma Knife Society, Seoul, Korea, May 21- 25, 2006, PS-PH5.