10 years of cranioTOP®

A cordial welcome to the homepage of CLinstruments .
cranioTOP® -cranioplasty has been introduced to the neurosurgical community 10 years ago during the industrial exhibition of the 2007 annual convention of tne German Neorosurgical Society in Leipzig.
Since then we could supply a lot of your patients witn our customized cranioplasties. We thank all our colleagues for their support and confidence in our products which by this means have been crowned so much with success. We are looking forward to wecome you at our booth during the DGNC meeting in Magdeburg May 2017.

Yours sincerely,



From CT to an individually tailored cranioplasty

Drawbacks of commonly implanted cranioplasties

Polymethylmethylacrylate PMMA:
Exothermal reaction while hardening in situ with production of crystallines. Toxic and allergic. High rate of infection and rejection. Often unsatisfying cosmetic results.

Carbides (so-called ceramics):
Heavy and voluminous. Have to be inserted into the defect with all resulting risks of additional dissection of bone edges,the dura, dura plasty, venous sinuses and so on.
In case of so-called osteomimetic apatite carbide only low strength; fixation only possible with sutures!

Titanium-CNC-milled, melted or LASER-generated:
Voluminous and has to be inserted into the defect, with the undesirable consequences known from the carbides i.e. the skull has to be made suitable for the cranioplaasty.

Additionally artifact impairment of image quality in postoperative CT-and MRI-examinations.

Patient sensivity with resulting headaches while exposed to heat and cold



If you have any questions left.


CLinstruments GMBH
Nordwall 22-24
57439 Attendorn

Phone / Fax

Phone: +49 (0) 27 22 / 63 46 43-1
Fax: +49 (0) 27 22 / 63 46 43-3

For any questions left

Please don’t hesitate to contact us via the contact form and we will get in touch with you as soon as possible.

Our company history

In 1987 the company was established as CLinstruments, Medical Technologies and EDP-Consulting Corporation, based in Witten in North-Rhine-Westphalia, Germany by the neurosurgeon Dr. med. Karl-Dieter Lerch.

CLinstruments’ original activity was the production and distribution of the DORTMUNDER Microstereotaxis-System, developed by LERCH in 1985 . The essential aim of this system’s development was to re-integrate stereotaxis into the general and particulary minimal invasive and endoscopic practices of neurosurgery, enabling microsurgery by stereotaxis to become the direct forerunner to present day “navigation”, but still however surpassing navigation in targeted precision. Distributed by the ZEPPELIN Corporation the LERCH-DORTMUNDER system became in the years following the most often utilised Microstereotaxis-System in Germany.

CLinstruments (directed by the developer himself) stands at your disposal for replacement parts and, of course, for new acquisitions of complete microstereotaxis systems. The design of a titanium ventricle-draining-system CranioDRAIN®, followed, as well as LERCH´s development of a novel aneurysm-clip-system RingLOC®.

The best known of LERCH’s neurosurgical developments and patents is, of course, CranioFIX®, a rivet-like fastener to refix craniotomy bone flaps. (The brands RingLOC®, CranioFIX®, CranioFIXII® and CranioFIXresorb® are licenced to B.Braun-Aesculap, Inc..)

CLinstruments’ first TITANIUM cranioplasties were made in 1996 using analog production techniques. After recruiting Dipl.-Ing. Jürgen Ortmann as technical chief of staff and co-partner, development began with CAD-production titanium thin sheet cranioTOP®-cranioplasties, including registration of relevant patent applications and trademark protections. Since then cranioTOP®-cranioplasties have been implanted in clinical practice by the Neurosurgical Clinic of the Municipal Hospital of the City of Dortmund, these having been first introduced generally at the industrial exhibition acompanying the 2007 annual convention of German Society of Neurosurgery (Deutsche Gesellschaft für Neurochirurgie – DGNC) in Leipzig. Distribution has also already begun of a dedicated TITANIUM-screw-system for the fixation of cranioTOP®-cranioplasties.

European Patent No.:1806113