Crescent durotomy for midline posterior fossa lesions.

Objective: The conventional midline suboccipital craniectomy, the standard approach for posterior fossa lesions, involves ligation of the occipital sinus. Postoperative sequelae that could occur from ligation of the occipital sinus include hydrocephalus, cerebrospinal fluid (CSF) leak, and pseudomeningiocoele formation. The standard of practice of venous pathway preservation, as practiced elsewhere in the cranium, should also be attempted in the posterior fossa. In the current study, we compared postsurgical complications between conventional "Y" durotomy with the proposed crescent durotomy in patients with posterior fossa lesions who underwent midline suboccipital craniectomy.

Methods: The prospective data of 104 patients who underwent a midline suboccipital craniotomy for posterior fossa tumors between January 2011 and December 2015 was performed. Comparison of study variables was done between the durotomy techniques used.

Results: Of the 104 patients who formed the study population, 39 (37.5%) were women. While 75 patients underwent crescent durotomy, the remaining underwent the conventional "Y" durotomy. Among the postsurgical complications, there were no differences between groups in terms of their surgical site hematoma (2.7% vs 3.4%; P = 1.000) and edema (1.3% vs 0.0%; P = 1.000). The groups were also similar in terms of the incidence of postsurgical CSF leak (1.3% vs 6.9%; P = 0.187) and cranial nerve deficits (4.0% vs 6.9%; P = 0.617). However, more number of patients who underwent the "Y" durotomy had postoperative pseudomeningiocoele (2.7% vs 17.2%; P = 0.017).

Conclusions: The "crescent" durotomy is a novel dural opening technique which attempts to preserve the normal venous flow physiology. The crescent durotomy reduces the need for a duroplasty, facilitates a comfortable primary closure, thus reducing the risk of developing a postoperative pseudomeningiocoele.