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Featured researches published by Cornelis P. Maas.


Seminars in Surgical Oncology | 2000

Avoiding long-term disturbance to bladder and sexual function in pelvic surgery, particularly with rectal cancer.

Klaas Havenga; Cornelis P. Maas; Marco C. DeRuiter; Kees Welvaart; J. Baptist Trimbos

Urinary and sexual dysfunction are common problems after rectal cancer surgery, and the likely cause is damage to the pelvic autonomic nerves during surgery. In recent years, attention has been focused on preserving the autonomic nerves through a technique which is usually combined with total mesorectal excision or radical pelvic lymphadenectomy. The autonomic nerves consist of the paired sympathetic hypogastric nerve, sacral splanchnic nerves, and the pelvic autonomic nerve plexus. We will demonstrate the anatomy of the pelvic autonomic nerves and the relation of these nerves to the mesorectal fascial planes, and review the medical literature on sexual and urinary dysfunction after rectal cancer surgery with and without autonomic nerve preservation.


International Journal of Gynecological Cancer | 2002

A nerve‐sparing radical hysterectomy: guidelines and feasibility in Western patients

J.B.M.Z. Trimbos; Cornelis P. Maas; Marco C. DeRuiter; Alexander A.W. Peters; G.G. Kenter

Surgical damage to the pelvic autonomic nerves during radical hysterectomy is thought to be responsible for considerable morbidity, i.e., impaired bladder function, defecation problems, and sexual dysfunction. Previous anatomical studies and detailed study of surgical techniques in various Japanese oncology centers demonstrated that the anatomy of the pelvic autonomic nerve plexus permits a systematic surgical approach to preserve these nerves during radical hysterectomy without compromising radicality. We introduced elements of the Japanese nerve-preserving techniques and carried out a feasibility study in ten consecutive Dutch patients. The technique involved three steps: first, the identification and preservation of the hypogastric nerve in a loose tissue sheath underneath the ureter and lateral to the sacro-uterine ligaments; second, the inferior hypogastric plexus in the parametrium is lateralized and avoided during parametrial transsection; third, the most distal part of the inferior hypogastric plexus is preserved during the dissection of the posterior part of the vesico-uterine ligament. The clinical study showed that the procedure is feasible and safe, except possibly when used with very obese patients and patients with broad, bulky tumors. Surgical preservation of the pelvic autonomic nerves in radical hysterectomy deserves consideration in the quest to improve both cure and quality of life in cervical cancer patients.


Journal of Clinical Oncology | 2008

Causes of fecal and urinary incontinence after total mesorectal excision for rectal cancer based on cadaveric surgery: a study from the Cooperative Clinical Investigators of the Dutch total mesorectal excision trial

Christian Wallner; Marilyne M. Lange; Bert A. Bonsing; Cornelis P. Maas; Charles Wallace; Noshir F. Dabhoiwala; Harm Rutten; Wouter H. Lamers; Marco C. DeRuiter; Cornelis J. H. van de Velde

PURPOSE Total mesorectal excision (TME) for rectal cancer may result in anorectal and urogenital dysfunction. We aimed to study possible nerve disruption during TME and its consequences for functional outcome. Because the levator ani muscle plays an important role in both urinary and fecal continence, an explanation could be peroperative damage of the nerve supply to the levator ani muscle. METHODS TME was performed on cadaver pelves. Subsequently, the anatomy of the pelvic floor innervation and its relation to the pelvic autonomic innervation and the mesorectum were studied. Additionally, data from the Dutch TME trial were analyzed to relate anorectal and urinary dysfunction to possible nerve damage during TME procedure. RESULTS Cadaver TME surgery demonstrated that, especially in low tumors, the pelvic floor innervation can be damaged. Furthermore, the origin of the levator ani nerve was located in close proximity of the origin of the pelvic splanchnic nerves. Analysis of the TME trial data showed that newly developed urinary and fecal incontinence was present in 33.7% and 38.8% of patients, respectively. Both types of incontinence were significantly associated with each other (P = .027). Low anastomosis was significantly associated with urinary incontinence (P = .049). One third of the patients with newly developed urinary and fecal incontinence also reported difficulty in bladder emptying, for which excessive perioperative blood loss was a significant risk factor. CONCLUSION Perioperative damage to the pelvic floor innervation could contribute to fecal and urinary incontinence after TME, especially in case of a low anastomosis or damage to the pelvic splanchnic nerves.


Acta Obstetricia et Gynecologica Scandinavica | 2005

Anatomical basis for nerve-sparing radical hysterectomy: immunohistochemical study of the pelvic autonomic nerves

Cornelis P. Maas; Gemma G. Kenter; J. Baptist Trimbos; Marco C. DeRuiter

Background.  Autonomic nerve damage plays a crucial role in the etiology of bladder dysfunction, sexual dysfunction, and colorectal motility disorders that occur after radical hysterectomy. We investigated the extent and nature of nerve damage in conventional and nerve‐sparing radical hysterectomy.


Obstetrics & Gynecology | 2006

Innervation of the pelvic floor muscles : A reappraisal for the levator ani nerve

Christian Wallner; Cornelis P. Maas; Noshir F. Dabhoiwala; Wouter H. Lamers; Marco C. DeRuiter

OBJECTIVE: We investigated the clinical anatomy of the levator ani nerve and its topographical relationship with the pudendal nerve. METHODS: Ten female pelves were dissected and a pudendal nerve blockade was simulated. The course of the levator ani nerve and pudendal nerve was described quantitatively. The anatomical data were verified using (immuno-)histochemically stained sections of human fetal pelves. RESULTS: The levator ani nerve approaches the pelvic-floor muscles on their visceral side. Near the ischial spine, the levator ani nerve and the pudendal nerve lie above and below the levator ani muscle, respectively, at a distance of approximately 6 mm from each other. The median distance between the levator ani nerve and the point of entry of the pudendal blockade needle into the levator ani muscle was only 5 mm. CONCLUSION: The levator ani nerve and the pudendal nerve are so close at the level of the ischial spine that a transvaginal “pudendal nerve blockade” would, in all probability, block both nerves simultaneously. The clinical anatomy of the levator ani nerve is such that it is prone to damage during complicated vaginal childbirth and surgical interventions. LEVEL OF EVIDENCE: II-3


British Journal of Surgery | 1998

Radical and nerve‐preserving surgery for rectal cancer in the Netherlands: a prospective study on morbidity and functional outcome

Cornelis P. Maas; Y. Moriya; W. H. Steup; G.M. Kiebert; W. M. Klein Kranenbarg; C.J.H. van de Velde


European Journal of Cancer | 2009

Risk factors for sexual dysfunction after rectal cancer treatment

Marilyne M. Lange; Corrie A.M. Marijnen; Cornelis P. Maas; Hein Putter; H.J.T. Rutten; Anne M. Stiggelbout; E. Meershoek-Klein Kranenbarg; C.J.H. van de Velde


International Journal of Gynecological Cancer | 2006

An observational longitudinal study to evaluate miction, defecation, and sexual function after radical hysterectomy with pelvic lymphadenectomy for early-stage cervical cancer

Q.D. Pieterse; Cornelis P. Maas; M.M. ter Kuile; M. Lowik; M.A. van Eijkeren; J.B.M.Z. Trimbos; G.G. Kenter


Ejso | 2000

A prospective study on radical and nerve-preserving surgery for rectal cancer in The Netherlands

Cornelis P. Maas; Y. Moriya; W. H. Steup; E. Klein Kranenbarg; C.J.H. van de Velde


European Urology | 2008

The contribution of the levator ani nerve and the pudendal nerve to the innervation of the levator ani muscles; a study in human fetuses.

Christian Wallner; Julia van Wissen; Cornelis P. Maas; Noshir F. Dabhoiwala; Marco C. DeRuiter; Wouter H. Lamers

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Marco C. DeRuiter

Leiden University Medical Center

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C.J.H. van de Velde

Leiden University Medical Center

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G.G. Kenter

Leiden University Medical Center

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Gemma G. Kenter

Netherlands Cancer Institute

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Marilyne M. Lange

Leiden University Medical Center

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J. Baptist Trimbos

Leiden University Medical Center

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J.B.M.Z. Trimbos

Leiden University Medical Center

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