Dr. Ismail Shafik Publication

Role of the longitudinal smooth muscle coat in the ileal motile activity: Evidence of ileo–ileal inhibitory reflex

Ahmed Shafik, Ali A Shafik, Ismail A Shafik

Ileal distension initiated circular muscle contraction only in the presence of the overlying longitudinal muscle, which appears to transmit the electrical activity to the circular muscle upon ileal distension. Ileal contraction is suggested to initiate ileal hypotonia in the proximal and distal ileal segments mediated through an ‘ileo–ileal inhibitory reflex’ that leads to aboral progress of the proximally and distally located chyme.

The motor efficacy of the artificial colonic pacemaker in colonic inertia patients

Ahmed Shafik , Olfat El-Sibai, Ali A Shafik, Ismail Ahmed Shafik

Colonic pacing evoked electric waves in colonic inertia patients and effected balloon expulsion. We postulate that the pacemaker generates electric waves which spread along pacemaker branches that are composed of interstitial cells of Cajal and nerve fibers of the enteric nervous plexus and effect colonic mass contraction. Ex-pacemaker stimulation presumably leads to local activation of interstitial cells of Cajal and segmental step-wise contraction.

Effect of colonic distention on ileal motor activity with evidence of coloileal reflex

Ahmed Shafik, Ali A Shafik, Ismail A Shafik

Chyme delivery from the ileum to the colon is controlled by various neurologic and hormonal factors, many of which remain to be identified. In this report, we investigated the effect of colonic distention on ileal motility with the aim of identifying the mechanism of chyme delivery from the ileum to the colon. The right colon of 16 healthy volunteers (12 men and 4 women; mean age 36+/-9 years standard deviation) was distended by a balloon that was filled with saline solution in increments of 20 ml.

Study of the functional activity of the cecocolonic junction with identification of a “physiologic sphincter”, “cecocolonic inhibitory reflex” and “ileocecal excitatory reflex”

Ahmed Shafik, Ali A Shafik, Ismail A Shafik, Randa M Mostafa

Radiologic, endoscopic, and histomorphologic studies have suggested the presence of a sphincter at the cecocolonic junction (CCJ), while some investigators have denied its existence. To investigate the physiologic activity at the CCJ, the right colon was exposed during right hemicolectomy for early colonic cancer in 11 patients (mean age 43.6+/-12.3 years; 8 men).

Electrophysiologic identification of the location of the colonic pacemakers in humans: further study

Ahmed Shafik , Olfat El-Sibai, Ali A Shafik, Ismail Ahmed Shafik

We recently defined the sites of four colonic pacemakers that appear to generate the electric waves assumed to be responsible for colonic motility. We hypothesized that a dysfunction of one or more of these pacemakers might interfere with the generation of electric waves and the colonic motility. This hypothesis was investigated in the current communication. The tests were performed during the repair of a huge incisional hernia of 8 subjects (5 F, 3 M; mean age 42.8 +/- 3.3 SD years).

Colosigmoid junction: a study of its functional activity with identification of a physiologic sphincter and involvement in reflex actions

Ahmed Shafik , Olfat El-Sibai, Ali A Shafik, Ismail Ahmed Shafik

The colosigmoid junction (CSJ) marks the termination of the descending colon (DC) and the beginning of the sigmoid colon (SC); it is a fixed area in the retroperitoneum. At this site where two functionally different areas meet, we hypothesized the presence at the CSJ of a physiologic sphincter that regulates the passage of gut contents from the DC to the SC. This hypothesis was investigated for this communication. Eight subjects (mean age 36.6 +/- 4.7 SD years, 6 women) were studied during surgical repair of incisional hernia or laparotomy.

Colonic pacing in patients with constipation due to colonic inertia

Ahmed Shafik , Olfat El-Sibai, Ali A Shafik, Ismail Ahmed Shafik

Colonic pacing produces electrical activity in patients with TCI. This method can be applied for the treatment of constipation in these patients.

Role of positive anorectal feedback in rectal evacuation: the concept of a second defecation reflex: the anorectal reflex

Ahmed Shafik, Ali A Shafik, Ismail Ahmed Shafik

Rectal contraction at defecation is suggested to be maintained by positive anorectal feedback evoked by continuous passage of stool through the rectal neck. This feedback appears to be affected through an anorectal excitatory reflex (ARR), which produces rectal contraction upon stimulation of anal stretch receptors. Abortion of this reflex by anal anesthetization seems to result in failure of the rectum to contract and in excessive straining to achieve rectal evacuation. ARR thus is suggested to be a second defecation reflex necessary to continue defecation, whereas the rectoanal inhibitory reflex is the primary reflex. The role of the ARR in pathogenesis of constipation and its utility in spinal cord injury need to be investigated.

Role of sympathetic innervation in the defecation mechanism: a novel concept of its function

Ahmed Shafik , Olfat El-Sibai, Ali A Shafik, Ismail Ahmed Shafik

Sympathetic rectal innervation may have a role during both the filling and evacuation phases of the defecation mechanism. During rectal filling, it most likely maintains rectal compliance. During evacuation in cases of rectal sympathetic block or denervation, a larger volume than usual of rectal distension is needed to induce rectal contraction and evacuation.

International Congress Presentations

1- 1st Congress of the Mediterranean Society of Pelvic Floor Disorders

• Date: Oct 24-26, 2002 | Location: Cairo, Egypt

2- ECCP 2003, European Council for Coloproctology

• Date: May 31 – Jun 4, 2003 | Location: Athens, Greece

3- 7th World Polydisciplinary Congress OESO

• Date: Aug 31 – Sept 4, 2003 | Location: Paris, UNESCO, France

4- Joint Meeting: European Group of Perinatology & Mediterranean Society of Coloproctology

• Date: March 25-27, 2004 | Location: Sharm El-Sheikh, Egypt

5- Joint Meeting: Mediterranean Society of Coloproctology & Mediterranean Society of Pelvic Floor Disorders

• Date: April 6-8, 2006 | Location: Cairo Sheraton Hotel, Egypt

6- XXI Biennial Congress of International Society of University Colon & Rectal Surgeons

• Date: June 25-28, 2006 | Location: Istanbul, Turkey

7- 5th Annual Meeting of the Mediterranean Society of Pelvic Floor Disorders

• Date: April 5-7, 2007 | Location: El-Saraya Floating Boat, Cairo, Egypt

8- 6th Biennial Meeting of MSCP

• Date: Feb 1-2, 2008 | Location: Rome, Italy

9- 6th Annual Meeting of the Mediterranean Society of Pelvic Floor Disorders (MSPFD)

• Date: April 3-5, 2008 | Location: Le Meridien Pyramids, Cairo, Egypt

10- 22nd Congress of International Society of University Colon and Rectum Surgeons

• Date: Sept 13-19, 2008 | Location: San Diego, California, USA

Professional Memberships

• International Society of University Colon and Rectum Surgeons, USA

• American Society of Colon and Rectum Surgeons, USA

• Mediterranean Society of Coloproctology, Italy

• Mediterranean Society of Pelvic Floor Disorders, Egypt

• Gynecology Society, New York

• Pudendal Nerve Society, Belgium