Our study involves male participants aged 18-70 years old suffering from erectile dysfunction and not responding to oral PDE5Is All patients are sexually active. They had no history of pelvic or spinal surgeries or trauma. Patients will be recruited from the Andrology department and outpatient clinics - Kasr Alainy- Cairo University hospitals.

The study will be conducted in the ultrasound unit in the Radiology department- Kasr Alainy- Cairo University hospitals.

Botulinum neurotoxin (BoNT) is produced by Clostridium botulinum, an anaerobic ,gram-positive bacterium. Poisoning with BoNT can cause botulism, resulting in generalized paralysis, respiratory failure, and death .There are seven serotypes of BoNT: A, B, C1, D, E, F, and G. BoNT-A is the most commonly used serotype for medical purposes.

Since its first use in 1977 for the treatment of strabismus in children, BoNT-A has since been used in aesthetic medicine and for the treatment of a number of disorders associated with overactive striated muscles, such as strabismus, esotropia, exotropia , focal dystonia, spasticity, and movement disorders.

BoNT-A has also been used in the management of some smooth-muscle disorders, such as achalasia, oesophageal spasm , ptyalism, hyperhidrosis, and intrinsic rhinitis, blepharospasm, muscle spasms and spasticity, axillary hyperhidrosis, and neurogenic detrusor muscle overactivity of the urinary bladder.

The International Index of Erectile Function Questionnaire (IIEF-5) is a questionnaire used by patients suffering from Erectile dysfunction to subjectively grade their condition. The score range from 5-25. and the erection status is classified into five categories based on the score: severe (5-7), moderate (8-11), mild to moderate (12-16), mild (17-21), no erectile dysfunction (22-25). The higher the score, the better the erection state.

An elastosonographic method was introduced as a new ultrasound technique that provides information regarding the rigidity of tissues rather than their morphology. There are two types of elastosonographic methods: strain elastosonography and shear wave elastosonography (SWE). The unit used is kilopascals. The lower the values, the better the outcome. Rigid penis has stiffer tissues which have lower SWE values.

The International Index of Erectile Function Questionnaire (IIEF-5) is a questionnaire used by patients suffering from Erectile dysfunction to subjectively grade their condition. The score range from 5-25. and the erection status is classified into five categories based on the score: severe (5-7), moderate (8-11), mild to moderate (12-16), mild (17-21), no erectile dysfunction (22-25).