Preservation of the greater occipital nerve during suboccipital craniectomy results in a paradoxical increase in postoperative headaches

Occipital Neuralgia following Acoustic Neuroma Resection

Background While postoperative outcomes of acoustic neuroma (AN) resection commonly consider hearing preservation and facial function, headache is a critical quality of life factor. Postoperative headache is described in the literature; however, there is limited discussion specific to occipital neuralgia (ON) following AN resection.

Objective The aim of this study is to investigate the effectiveness of conservative management and surgery.

Methods We conducted a retrospective review of 872 AN patients who underwent resection at our institution between 1988 and 2017 and identified 15 patients (1.9%) that met International Classification of Headache Disorders criteria for ON.

Results Of the 15 ON patients, surgical approaches included 13 (87%) retrosigmoid (RS), one (7%) translabyrinthine (TL), and one (7%) combined RS + TL. Mean clinical follow-up was 119 months (11–263). Six (40%) patients obtained pain relief through conservative management, while the remaining nine (60%) underwent surgery or ablative procedure. Three (38%) patients received an external neurolysis, four (50%) received a neurectomy, one (13%) had both procedures, and one (13%) received two C2 to 3 radio frequency ablations. Of the nine patients who underwent procedural ON treatment, seven (78%) patients achieved pain relief, one patient (11%) continued to have pain, and one patient (11%) was lost to follow-up. Of the six patients whose pain was controlled with conservative management and nerve blocks, five (83%) found relief by using neuropathic pain medication and one (17%) found relief on nonsteroidal anti-inflammatory drug.

Conclusion Our series demonstrates success with conservative management in some, but overall a minority (40%) of patients, reserving decompression only for refractory cases.

A Laboratory Investigation on a Tailored Skin and Muscle Flap Variant for the Retrosigmoid Approach

Introduction An anatomical study was conducted to test a modified C-shaped flap designed for patients undergoing a keyhole approach and/or minicraniotomy for retrosigmoid approach (KRSA).

Materials and Methods Ten heads specimens were used. The surgical technique investigated was based on a 4-cm C-shaped skin incision with medial convexity (placed 8 cm laterally to the external occipital protuberance, with the lower edge terminating 1.5 to 2 cm above the mastoid tip), which followed by careful subperiosteal dissection and completed by reflecting and securing the skin flap layer anteriorly and the muscle flaps superiorly and inferiorly by stitches. Anatomical findings, including depth of surgical corridor till to the cerebellopontine cistern (CPC) as well as the sparing of neurovascular structures, were evaluated in every specimen.

Results Twenty surgical approaches to CPC were conducted, resulting in a short working distance to the target (32 mm) without any need for a self-retaining retractor. In every specimen, the integrity of occipital muscles and cutaneous nerves was maintained, and a solid multilayer closure was always achieved. These data suggest that landmarks-based design of this C-shaped incision could be helpful in avoiding damages to the soft tissues encountered during KRSA.

Conclusion This modified approach provides a wide surgical corridor to access the CPC while ensuring the minimal invasiveness of the standard S-shaped incision. Compared with the latter, it preserves better the integrity of the surrounding soft tissues and appears less likely to cause any iatrogenic injury to occipital muscles and cutaneous nerves.

Impact of C-shaped skin incision on surgical operability in the retrosigmoid approach: when a good start is half of the job

BACKGROUND

The retrosigmoid approach (RSA) is one of the routes of choice to approach tumors and vascular lesions of the cerebellopontine angle. Among different types of skin incisions and soft tissue dissection techniques, the most widely used variants comprise the straight/lazy S-shaped and the C-shaped incisions. Several reports discuss advantages in terms of functional and clinical outcomes of the C-shaped incision, but scientific considerations about the critical impact of this kind of incision on surgical operability are still extremely limited.

OBJECT

Authors comparatively analyze the advantage provided by C-shaped incision in RSA in terms of anatomic exposure and surgical operability, compared with straight/lazy S-shaped one.

METHODS

A comparative microanatomical laboratory investigation was conducted. The operability score (OS) was applied for quantitative analysis of surgical operability.

RESULTS

C-shaped incision, providing a significant reduction of the overall working distance (-13%) together with an overall increase of the maneuverability area (+ 204.9%), did improve the conizing effect on the surgical corridor. It optimized overall maneuverability of surgical instruments, in terms of angle of attack (+ 27.7%), as well as maneuverability arc (+ 122%), on the entire surgical field. C-shaped incision ensured good operability on all surgical targets (OS ranging from 2 to 3), most significantly improving surgical maneuverability at the porus trigeminus and internal acoustic meatus.

CONCLUSION

C-shaped incision in the RSA significantly improves anatomic exposure and surgical operability as compared with straight/lazy S-shaped incision.

A Novel Technical Refinement of Microvascular Decompression: Pain Relief and Complication Rate in a Consecutive Series of Patients With Trigeminal Neuralgia

BACKGROUND

Microvascular decompression (MVD) represents a milestone for the treatment of trigeminal neuralgia (TN). Nevertheless, several complications still occur and may negatively affect the outcome. We recently proposed some technical nuances for complication avoidance related to MVD.

OBJECTIVE

To verify the efficacy of the proposed refinement of the standard MVD technique in terms of resolution of the pain and reduction of complication rates.

METHODS

We analyzed surgical and outcome data of patients with TN using a novel surgical refinement to MVD, over the last 4 yr. Outcome variables included pain relief, facial numbness, muscular atrophy, local cutaneous occipital and temporal pain or numbness, cerebellar injury, hearing loss, cranial nerve deficits, wound infection, and cerebrospinal fluid (CSF) leak. Overall complication rate was defined as the occurrence of any of the aforementioned items.

RESULTS

A total of 72 consecutive patients were enrolled in the study. Pain relief was achieved in 91.6% and 88.8% of patients at 1- and 4-yr follow-up, respectively. No patient reported postoperative facial numbness during the entire follow-up period. The incidence of CSF leak was 1.4%. One patient developed a complete hearing loss and another a minor cerebellar ischemia. There was no mortality. The overall complication rate was 5.6%, but only 1.4% of patients experienced permanent sequelae.

CONCLUSION

The proposed refinement of the standard MVD technique has proved effective in maintaining excellent results in terms of pain relief while minimizing the overall complication rate associated with this surgical approach.

Postoperative Headache after Undergoing Acoustic Neuroma Surgery via the Retrosigmoid Approach

To estimate the duration of postoperative headache after surgery for acoustic neuroma and the effects of age, sex, tumor size, extent of tumor resection, type of skin incision, surgical duration, hearing preservation, and postoperative facial nerve palsy. This retrospective review analyzed clinical data from 97 patients who had undergone surgery for unilateral acoustic neuroma via the retrosigmoid approach >1 year previously. We investigated whether patients had headache at hospital discharge and during attendance at outpatient clinics. We classified postoperative headache as grade 0 (no headache), 1 (tolerable headache without medication), or 2 (headache requiring medication). The period of headache was defined as the interval in days between surgery and achievement of grade 0. The period of medication for headache was defined as the interval in days between surgery and achievement of grade 0 or 1. Kaplan-Meier analysis revealed median durations of medication and headache of 81 and 641 days, respectively. Headache was cured significantly earlier in patients who underwent surgery using a C-type skin incision (P < 0.001). Headache persisted significantly longer among patients who underwent a shorter surgical procedure (P < 0.02). Multivariate analysis confirmed the type of skin incision as a factor independently associated with duration of postoperative headache. Postoperative headache was cured in the majority of patients within about 2 years after surgery. The C-type skin incision is likely beneficial for reducing the duration of postoperative headache, although headache persisted in a small number of patients.