Michael R. Gaab: March 11, 1947–December 29, 2024

Michael Robert Gaab was born on March 11, 1947, in Landau, a small town in Palatinate, Germany. His father was the chief surgeon at the City hospital in Annweiler. He passed the high school exam in 1966. He studied medicine at the Julius-Maximilian-University in Würzburg and the University of Kiel. On July 24, 1972, he received his MD degree from the University of Würzburg. In August 1973, Gaab started his residency training in the Department of Neurosurgery at the University of Würzburg. On December 11, 1974, he defended his Dr. med. thesis “Ultrastructure of the thalamus and osmoregulation” with “summa cum laude.” In August 1979, he received his board certification as a neurosurgeon. In 1981, he successfully accomplished his “Habilitation” and became “Privatdozent.”

Gaab was deeply influenced by his first supervisor at the Department of Neurosurgery in Würzburg, Prof. Joachim Gerlach, and his provisional successor, Prof. Gerhard Lausberg.

In Würzburg, Gaab began his research on intracranial pressure and became the chair of the section on Intracranial Pressure—Brain Edema—Cerebral Blood Flow of the German Society of Neurosurgery, a position he held for many years. He also supervised numerous doctoral theses, which led to a collaboration with the university's computing center. Through this, Gaab contributed to the rapid development of computer technology in both scientific and medical applications. He developed techniques of intracranial pressure measurement and received several awards for his work.

From 1982 to 1984, Gaab moved to the Neurosurgical Department of the AKH at the University of Vienna, which was headed by Prof. Wolfgang Koos, to improve his training in vestibular schwannoma surgery. While in Vienna, he continued his research on intracranial pressure measurement and head trauma. Additionally, he became the head of Pediatric Neurosurgery.

From 1984 to 1992, Gaab served as an Associate Professor at the Department of Neurosurgery at the Hannover Medical School under Prof. Hermann Dietz. There, he quickly became involved in extensive clinical and scientific activities, engaging many colleagues from the department and establishing various research projects, including transcranial Doppler sonography, neurophysiological studies, including evoked potentials, nuclear medicine investigations of neurosurgical patients using PET and SPECT, Xenon-CT for the assessment of cerebral blood flow and reserve capacity.

Despite resistance from vascular surgeons, he performed over 100 microsurgical endarterectomies on the carotid and vertebral arteries with excellent outcomes. He also introduced the surgical stabilization of lumbar spine fractures using internal fixation, overcoming significant resistance from the trauma surgery department. Additionally, he developed a double-threaded titanium screw for the surgical stabilization of dens axis fractures and achieved great success in the treatment of other cervical spine instabilities.

Under his leadership, a national multicenter study (GUDHIS) on the use of dexamethasone in traumatic brain injury was conducted, leading to the discontinuation of corticosteroid therapy for traumatic brain injury. Gaab also organized one of the first conferences on intraoperative ultrasound in neurosurgery (Neurosurgical Ultrasound Conference, Hannover, January 20–21, 1989).

Emerging issues with hydrocephalus shunt valves prompted him to initiate valve testing and establish the Commission for Technical Standards and Norms, where he served as the long-time spokesperson. He also led the neurosurgical delegation at DIN (Deutsches Institut für Normung) meetings for the standardization of shunt valves and aneurysm clips.

On March 1, 1992, Gaab received a call as a University professor to the department of neurosurgery at the University of Greifswald, where he stayed for 11 years. His major contribution in the Greifswald period was clearly the advancement of endoscopic surgical techniques in neurosurgery. Encouraged by the endoscopic sinus surgery of the ENT colleagues and a report of Griffith on “Endoneurosurgery”published in 1986 in Advances and Technical Standards in Neurosurgery,[1] Gaab started to deal with endoscopic techniques already in 1987 in Hannover. He contacted Karl Storz in Tuttlingen and convinced him to manufacture a rigid ventriculoscope in 1989, which has been known worldwide as the “Gaab scope.”[2] He preferred rigid Hopkins optics because of the brilliant optical quality. Gaab did pioneering work in the development of endoscopic surgical techniques and instruments for intraventricular tumors and cysts.[3] He was a founding member of the German Society of Neuroendoscopy and Endoscopic Neurosurgery and performed the first cadaver hands-on course of this society in 1995 in the anatomy dissection hall in Greifswald.

In addition to his clinical and scientific work, he served as the Medical Director at the University hospital for several years. Furthermore, he initiated the foundation of the Neurological Rehabilitation Hospital BDH in Greifswald. In addition to his remarkable clinical and scientific contributions, Gaab was a passionate pilot and diver. He obtained a commercial pilot license (ATPL) and became a flight instructor.

On February 1, 2003, Gaab became the Chief Surgeon of the Department of Neurosurgery at the Nordstadt Hospital, Hannover. He succeeded Madjid Samii as the head of this department. Gaab remained the Chief surgeon until his retirement in March 2013. During his time in Hannover, he continued with his academic focus on endoscopic, minimally invasive techniques. During this time, he received a grant from the Else Kröner Fresenius Stiftung for minimally invasive application of waterjet technology. Additionally, he promoted the endoscopic techniques with workshops and courses. For his continuous support of the Kazakh Neurosurgical Society, he was appointed as an Honorary Professor of Neurosurgery and Extraordinary Member of the Kazakh Neurosurgical Society in 2012.

Michael R. Gaab will remain in our thoughts forever. Our deepest condolences go to his family. May he rest in peace.

Publication History

Article published online:
02 April 2025

• References

• 1 Griffith HB. Endoneurosurgery: endoscopic intracranial surgery. in: Symon L, Brihaye J, Guidetti B. et al. (eds). Advances and Technical Standards in Neurosurgery. Wien: Springer; 1986. , Vol. 14, pp. 2-24
• 2 Gaab MR. A universal neuroendoscope: development, clinical experience, and perspectives. Childs Nerv Syst 1994; 10: 481 (Abstract)
• 3 Gaab MR, Schroeder HWS. Neuroendoscopic approach to intraventricular lesions. J Neurosurg 1998; 88 (03) 496-505