Many studies show that PPIs are not more effective than placebos in treating LPR.When medical management fails, Nissen fundoplication can be offered. However, patients should be advised that surgery may not result in complete elimination of LPR symptoms and even with immediate success, recurrence of symptoms later on is still possible.One way to assess treatment outcomes for LPR is through the use of voice quality measures. Both subjective and objective measures of voice quality can be used to assess treatment outcomes. Subjective measures include scales such as the Grade, Roughness, Breathiness, Asthenia, Strain Scale (GRBAS); the Reflux Symptom Index; the Voice Handicap Index (VHI); and a voice symptom scale. Objective measures often rely on acoustic parameters such as jitter, shimmer, signal-to-noise ratio, and fundamental frequency, among others. Aerodynamic measures such as vital capacity and maximum phonation time (MPT) have also been used as an objective measure. However, there is not yet a consensus on how best to use the measures or which measures are best to assess treatment outcomes for LPR. Procedures
There is tentative evidence from non-controlled trials that oral neuromuscular training may improve symptoms. This has been approved by the UK National Health Service (NHS) for supply on prescription from 1 May 2022. History
LPR was not discussed as a separate condition from GERD until the 1970s and 1980s. However, at around the same time that GERD was first recognized as a clinical entity in the mid-1930s, a link between gut symptoms and airway disease was suggested.
Diagnosis
Besides the clinical picture, fasting VIP plasma level may confirm the diagnosis, and  CT scan and somatostatin receptor scintigraphy are used to localise the tumor, which is usually metastatic at presentation.Tests include:

Blood chemistry tests (basic or comprehensive metabolic panel)
CT scan of the abdomen
MRI of the abdomen
Stool examination for the cause of diarrhea and electrolyte levels
Vasoactive intestinal peptide (VIP) level in the blood

Treatment
The first goal of treatment is to correct dehydration. Fluids are often given through a vein (intravenous fluids) to replace fluids lost in diarrhea. The next goal is to slow the diarrhea. Some medications can help control diarrhea. Octreotide, which is a human-made form of the natural hormone somatostatin, blocks the action of VIP.The best chance for a cure is surgery to remove the tumor. If the tumor has not spread to other organs, surgery can often cure the condition.For metastatic disease, peptide receptor radionuclide therapy (PRRT) can be highly effective. This treatment involves attaching a radionuclide (Lutetium-177 or Yttrium-90) to a somatostatin analogue (octreotate or octreotide). This is a novel way to deliver high doses of beta radiation to kill tumours. Some people seem to respond to a combination chemo called capecitabine and temozolomide but there is no report that it totally cured people of VIPoma. Prognosis
Surgery can usually cure VIPomas. However, in one-third to one-half of patients, the tumor has spread by the time of diagnosis and cannot be cured. References

Jensen RT, Norton JA. Endocrine tumors of the pancreas and gastrointestinal tract. In: Feldman M, Friedman LS, Brandt LJ, eds.